SPONSORS

Thanks to those who have helped make ICOTOM18 possible

EDAX is a leading provider of innovative materials characterization systems encompassing Energy Dispersive Spectroscopy (EDS), Wavelength Dispersive Spectrometry (WDS), Electron Backscatter Diffraction (EBSD) and X-ray Fluorescence (XRF).

EDAX products include standalone tools for EDS, EBSD and WDS, integrated tools for EDS-EBSD, EDS-WDS, and EDS-EBSD-WDS, and a free-standing micro-XRF bench-top elemental analyzer providing small and micro-spot x-ray analysis and mapping.

EDAX develops the best solutions for micro- and nano-characterization, where elemental and/or structural information is required, making analysis easier and more accurate.

EDAX designs, manufactures, distributes and services products for a broad range of industries, educational institutions and research organizations. http://www.edax.com/

Brigham Young University, Department of Mechanical Engineering. https://me.byu.edu/node

Located at the heart of both the quintessential ‘great outdoors’ and the vibrant Utah engineering community, BYU Mechanical Engineering department takes pride in preparing some of the nation’s brightest minds to pursue careers with impact. With a world-famous capstone program, and a mentoring emphasis that involves more than 70% of those undergraduates directly in faculty guided research, the department ranks amongst the highest in the nation for channeling students into PhD programs. A strong graduate program with over 120 MS and PhD students supports the ‘inspiring learning’ gained by more than 1300 enrolled undergraduates; research focuses range from biomechanics to robotics, including three decades of research in EBSD and microstructure design.

Exhibitors

Oxford Instruments NanoAnalysis provides leading-edge tools that enable materials characterization and sample manipulation at the nanometer scale.

Used on electron microscopes (SEM and TEM) and ion-beam systems (FIB), our tools are used for R&D across a wide range of academic and industrial applications including metallurgy, mining, semiconductors, renewable energy, and forensics. https://www.oxford-instruments.com/

Bruker offers a broad range of systems for EBSD, EDS, WDS X-ray spectrometry, and micro-X-ray fluorescence and nanomechanical testing technologies on the electron microscope. Bruker unique solutions for EBSD include OptimusTM for TKD, ArgusTM for microstructure visualization, Dynamic Simulation, and QUBE for advanced 3D analysis. https://www.bruker.com/

EBSD Analytical offers complete micro-structural analysis services for scientists and researchers worldwide. Our analysis services include texture, grain size, phase differentiation, grain boundary/misorientation, stress/strain, along with EDS characterization. With over 20 years experience preparing and analyzing thousands of EBSD samples, we are confident we can meet your analysis needs. Turn around times are quick and accurate results are guaranteed. Our goal is to consistently exceed customers’ expectations. http://www.ebsdanalytical.com/

BLGVantage specializes in the development of software and hardware tools for High Resolution (HR) EBSD in the field of materials science. We are interested in looking deeper at the data EBSD provides us. Our flagship software application CrossCourt4 for Strain Analysis is in use in a large number of research laboratories across the globe and supported by scientists and software engineers based in the UK, North America and Asia. http://www.hrebsd.com/wp/

SPONSORS

The NanoMEGAS ASTAR system for TEM allows nm resolution orientation-phase maps combined with precession electron diffraction. Applications including strain mapping (Topspin), ab initio structural determination (ADT-3D), grains statistic (ASTAR), and amorphous short range order bond length (e-PDF) characterization can be installed on all new or existing TEM microscopes. http://www.nanomegas.com/

Based in Dortmund Germany, with worldwide representation, Kammrath and Weiss is the market leader of tensile-compression-heating modules for SEM and FIB. We have been providing high-precision, electro-mechanical accessories and devices for microscopy for over 25 years. Our product line includes systems and devices in 5 major categories:

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• Sample stages: Custom designed stages and sample holders

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Please contact George Lanzarotta (George.lanzarotta@kammrathandweiss.com) for inquiries in North America or visit https://www.kammrath-weiss.com/en/ for Europe and other territories

TSL Solutions KK is based in Japan. It supports the EDAX EBSD business as an agent in Japan and the surrounding region. In addition, TSL Solutions is a manufacturer of In-Situ testing apparatuses such as tensile stages, heating stages and bending stages. Its In-Situ apparatuses are designed specifically for EBSD observation of dynamic microstructure changes. http://www.tsljapan.com/

Gatan, Inc. is the world's leading manufacturer of instrumentation and software used to enhance and extend the operation and performance of electron microscopes. Gatan products, which are fully compatible with nearly all electron microscope models, cover the entire range of the research process—from specimen preparation and manipulation to imaging and analysis. The Gatan brand name is recognized and respected throughout the worldwide scientific community and has been synonymous with high quality products and leading technology for more than 50 years. Gatan is headquartered in Pleasanton, California, U.S.A. For more information, visit: http://www.gatan.com/.

Xnovo Technology ApS, founded in December 2012, is the commercial result of more than 15 years of synchrotron and diffraction imaging research at the Technical University of Denmark.

Xnovo specializes in the development of innovative 3D X-ray imaging solutions for engineers and scientists with emphasis on 3D crystallographic imaging tools for applications within engineering, materials sciences & geosciences.

The first commercial application of Xnovo’s patent portfolio is Laboratory Diffraction Contrast Tomography (LabDCT) in partnership with Carl Zeiss X-ray Microscopy Inc. LabDCT is a unique offering for ZEISS Xradia 520 Versa X-ray microscopes providing non-destructive 3D crystallographic imaging of polycrystalline materials. http://xnovotech.com/

Throughout the world, ZEISS stands for the highest quality and reliability. Carl Zeiss Microscopy is part of the Carl Zeiss group, a leading organization of companies operating worldwide in the optical and opto-electronical industry. As the world's only manufacturer of light, X-ray and electron/ion microscopes, Carl Zeiss Microscopy offers tailor-made systems for industry, materials research and academia. A dedicated and well-trained sales force, an extensive support infrastructure and a responsive service team enable customers to use their ZEISS microscope systems to their full potential. https://www.zeiss.com/microscopy/us/about-us/welcome.html

BlueQuartz Software specializes in the development and integration of computational tools from the materials science and engineering domain into the DREAM.3D ecosystem. BlueQuartz Software's most recent activities resulted in the addition of over 100 image processing filters into the DREAM.3D data analysis package greatly expanding the range of data processing capabilities of DREAM.3D. BlueQuartz Software employs both dedicated software engineers and materials science and engineering domain experts to quickly and efficiently bring advanced computational tools to the practicing engineer and researcher. By making DREAM.3D available under a permissive open-source license BlueQuartz Software is helping researchers worldwide accelerate their data analysis. http://www.bluequartz.net/

SPONSORS

With friendly support

The Minerals, Metals & Materials Society (TMS) is a professional association that connects minerals, metals, and materials scientists and engineers who work in industry, academia, and government positions around the world. https://www.tms.org

IOP Publishing is an international, not-for-profit, learned society publisher of world-renowned journals, magazines, ebooks, conference proceedings and websites for the scientific community. These products and services enable researchers and research organisations to reach the widest possible audience for their research. We combine the culture of a learned society with global reach and highly efficient and effective publishing systems and processes. With offices in the UK, US, China and Japan, and staff in many other locations including Mexico and Sydney, we serve researchers in the physical and related sciences in all parts of the world.

IOP will publish the proceedings of ICOTOM 2017. Papers should be 6 to 8 pages in length and submitted by December 1, 2017. The papers will be reviewed and published in June 2018. For details on preparing and submitting your manuscript go to http://icotom2017.conferenceseries.iop.org.

COMMITEE

ICOTOM 18 ORGANIZATION

International Committee

Anthony Rollett USA (Chairman)

Matthew Barnett Australia

Olaf Engler Germany

Werner Skrotzki Germany

Kyuwhan Oh South Korea

Dorte Juul Jensen Denmark

Adam Morawiec Poland

Indradev Samajdar India

Satyam Suwas India

Liang Zuo China

João Quinta da Fonseca UK

Claude Esling France

Laszlo Toth France

Hirofumi Inoue Japan

Leo Kestens The Netherlands

Jerzy Szpunar Canada

Local Committee

Stuart Wright EDAX (co-chair)

David Fullwood Brigham Young University (co-chair)

Matt Nowell EDAX (co-chair)

Irene Beyerlein University of California Santa Barbara

Pamela Burnley University of Nevada Las Vegas

Sam Daly University of California Santa Barbara

David Field Washington State University

Eric Homer Brigham Young University

Oliver Johnson Brigham Young University

Mukul Kumar Lawrence Livermore National Laboratory

Asher Leff Drexel University

Rodney McCabe Los Alamos National Laboratory

Lowell Miyagi University of Utah

Tracy Nelson Brigham Young University

Srikanth Patala North Carolina State University

Warren Poole University of British Columbia

Michael Roach University of Mississippi Medical Center

Chad Sinclair University of British Columbia

Ashley Spear University of Utah

Sven Vogel Los Alamos National Laboratory

Rudy Wenk University of California Berkeley

Special thanks to the following for their assistance in organizing ICOTOM 18

Jason Murray Southwest Adventure Tours

Shandilee Richins Southwest Adventure Tours

Administrative staff of the Department of Mechanical Engineering at Brigham Young University

Staff at the Dixie Center

SCIENTIFIC PROGRAM

ICOTOM 18 SUNDAY 1

SUNDAY 8:00 Registration desk open at the Marriott Courtyard Hotel

Short Course

A Guide to Practical Crystallography and its Applications to Materials Textures

Practical Tutorial on MTEX

Instructors Marc De Graef Ralf Hielscher & David Mainprice

Room Marriott Courtyard A Marriott Courtyard B

8:30-10:30

Texture analysis of materials relies heavily on three fundamental topics: crystallography and symmetry; diffraction; and representation of orientations and rotations. In this tutorial, we will address all three topics in detail. We begin with a review of basic crystallography with an emphasis on practical approaches to crystallographic computations, both in direct and reciprocal space. Then we discuss symmetry operators, in particular the rotational symmetries of importance to materials textures. We conclude with a detailed overview of the representation of orientations/rotations in the conventional Euler representation as well as in several neo-Eulerian representations, including quaternions, Rodrigues-Frank vectors, and homochoric vectors. Participants are expected to have a basic knowledge of crystallography and diffraction.

MTEX is a very powerful Matlab toolbox for analyzing EBSD and XRD data, performing crystallographic calculations, modelling textures and analyzing plastic and elastic properties. The first half of the tutorial will introduce you into the basic concepts of MTEX while the second part will be devoted to guided exercises with the software. The part requires a laptop with Matlab version 2014b or newer installed. Prior Matlab knowledge is NOT required.

10:30-10:50 Break Break 10:50-12:30 Continuation Continuation

12:30 – 13:30 Lunch – many eateries nearby

Short Course

Practical Tutorial on Dream.3d Texture Analysis from Diffraction Data using MAUD Application Examples and Hands-on Tutorial

Instructors Michael Jackson & Anthony Rollett Luca Lutterotti & Sven Vogel

Room Marriott Courtyard A Marriott Courtyard B

13:30-15:30

The open-source software package Digital Representation Environment for the Analysis of Materials in 3D (DREAM.3D) is a freely available software tool that performs a wide range of functions for reconstructions of 3D microstructures, statistical analysis, and generation of representative volume elements. Course participants will learn the methodologies behind the analysis of 3D materials data, with a focus on practical application of workflows via hands-on tutorials. Participants will also learn how to utilize DREAM.3D to produce visualizations in the freely available software package ParaView. The goals of the workshop are to equip participants with the skills necessary to reconstruct, quantify, and analyze 3D materials data

Microstructural characterization with diffraction techniques such as synchrotron or neutron diffraction is a powerful tool in materials science, geology, and related fields of research. In this short course, we will demonstrate how the MAUD (Materials Analysis Using Diffraction) software can be used to extract texture and other microstructure parameters (phase fractions, micro-strains, domain sizes etc.) from diffraction data. The participant should have a working knowledge of diffraction techniques and crystallography. We will provide information on how to install MAUD on personal laptops prior to the tutorial and encourage interested participants to bring data of their own projects that we may be able to help with.

15:30-15:50 Break Break

15:50-17:30 Continuation Continuation

ICOTOM 18 MONDAY 2

MONDAY AM – General Sessions in Ballroom AB 8:00 Registration/Info Desk Open

8:30 – 8:50 Opening/ Logistics

8:50 – 9:20 Welcome: Professor Gerald Bryant, Dixie State University

9:20 – 9:50 Plenary: Dierk Raabe Textures Studied at Near Atomic-Scale

9:50 – 10:30 Plenary: Rudy Wenk How Textures Helped Us Understand Deformation in the Earth

10:30 – 10:40 Break

Session Deformation: Mg Rudy Wenk Recrystallization Advanced Materials Characterization

Chair(s) T Bieler & J da Fonseca

P Burnley & J Kanitpanyacharoen

F Cruz-Gandarilla R. McCabe B Lan & T Ruggles

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 10:40 – 11:10

H-G Brokmeier Comparison of in-situ tension and in-situ compression behavior of Mg-AZ80

S Merkel In-Situ Studies of Microstructures under Deep Earth Conditions: from Texture Analysis to Multigrain Crystallography

R Petrov Texture and microstructure of advanced high strength steel after fast heating and short annealing

J Kopeček Microstructure effects of mechanical alloying on SPS sintered Fe-Al-Si powders

M De Graef Dictionary Indexing Approach for Electron Diffraction Modalities

11:10 – 11:30

J Singh Failure behaviors of E-form and AZ31 Mg alloys: Crack initiation and propagation during mini-V-bending tests

L Miyagi Deformation and texture development in lower mantle mineral phases: What does seismic anisotropy in the deep Earth tell us about deformation?

S Janakiram Naik Texture evolution during partial recrystallization annealing in high strength automotive steels

H Mehtani Oxidation Kinetics of Steel: The Defining Role of Substrate Micro-texture

F Ram Improved spatial and angular resolution of EBSD-based texture measurement of deformed and fine-grained materials

11:30 – 11:50

L Jin Towards high ductility in magnesium alloys - the role of grain boundary misorientation and deformation compatibility

AK Mariyappan Deformation texture evolution of ω-Zr at high pressure

F Castro-Cerda The effect of the pre-heating temperature and heating rate on the textures of cold-rolled low-carbon steel

R Chulist Effect of temperature and crystallographic orientation on superelastic strain of FeNiCoAlTaB single crystals

V Mertinger Pole figure measurement methods for centerless X-ray diffractometers

11:50 – 12:10

JH Cho Texture and microstructure evolution of magnesium sheets during bending

J Gomez-Barreiro Preferred orientation in a linear viscous flow: High T torsion experiments on Diopside-Anorthite aggregates

K Nishimura Effects of initial microstructure/texture and cold-rolling reduction on texture and r-value in ferritic stainless steel sheets.

S Dhala Crystal Plasticity Finite Element Modeling of Polycrystal NiTi Shape Memory Alloy (SMA)

AD Rollett Quantification of local anisotropy and microstructure-property relationships using canonical correlation analysis

12:10 – 12:30

R Xin Variant selection of {10-12}-{10-12} double twins during the tensile deformation of Mg alloys

L Miyagi Special Presentation for Rudy Wenk

H Sandim Texture characterization of AISI 316 L steel processed by selective laser melting

S Kaboli Deformation Analysis of Alumina Compressed at High Pressure Using Electron Channeling Contrast Imaging (ECCI) and EBSD

F Brisset Geometric distortion corrections of EBSD Scans

12:30 – 14:00 Lunch: Garden Room

ICOTOM 18 MONDAY 3

MONDAY PM

14:00 – 14:40 Plenary: Ben Britton Deformation and Grain Growth of Hexagonal Metals: New Insights with

Conventional and High Resolution EBSD Techniques

14:40 – 15:20 Plenary: Tom Bieler Effects of Texture on Mesoscale Characterization and Modeling of

Heterogeneous Deformation

15:20 – 15:30 Break

Session Deformation: Ti Rudy Wenk Recrystallization Advanced Materials Characterization

Chair(s) B Diak L Miyagi & S Merkel R Petrov J Kopeček D Savage & R Hielscher

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 15:30 – 16:00

J Quinta da Fonseca Understanding the texture and anomalous recrystallization behaviour of warmed rolled CP-Ti

I Lonardelli Texture analysis from synchrotron and Neutron diffraction: Rietveld method applied to biological materials, commercial-pure Titanium and Shales from sedimentary basins

H Miura Effects of Nucleation at Shear bands on Texture Evolution in Cold-Rolled IF Steels

R McCabe Microstructure and Texture evolution during thermo-mechanical processing of low-symmetry metals

M Takamura In-house texture measurement using compact neutron source

16:00 – 16:20

J Jha Microstructure and texture Evolution during Thermo-Mechanical Processing of Ti-6Al-4V Titanium Alloy

L Morales Olivine-antigorite phase transformation: microstructures, phase boundary misorientation and seismic properties

A Després Texture development during static recrystallization of a warm and hot rolled ferritic stainless steels

O Van der Biest Reactive Texturing of Y-TZP and Ce-TZP in a 17 Tesla Magnetic Field

H-G Brokmeier Texture analysis with monochromatic neutrons at STRESS-SPEC

16:20 – 16:40

AD Rollett Microstructural and texture characterization and 3D modeling of Ti-6Al-4V alloys with different processing histories

D Mainprice The seismic properties of quartzites during the alpha-beta transition and the influence of texture

M Latypov Quantification of recrystallization simulation datasets by chord length distribution and principal component analysis

Y Zhang Texturation of polycrystalline NiMnGa alloys via mechanical training studied by in-situ neutron diffraction and SEM EBSD

Y Onuki Development and verification of simultaneous measurement system for texture and phase fraction by time-of-flight neutron diffraction at iMATERIA

16:40 – 17:00

K Chatterjee Study of residual stresses in Ti-7Al using theory and experiments

B Majumdar Role of Texture on Enhanced Magnetocaloric Effect in Heusler Alloys Following Stress Assisted Thermal Cycling

M Kucerakova Neutron and X-ray Diffraction Texture Analysis of Novel Al-Si-Mg Alloy

17:30 – 19:30 Reception: Marriott Courtyard Hotel

ICOTOM 18 TUESDAY 4

TUESDAY AM 8:00 Registration/Info Desk Open

8:30 – 9:10 Plenary: David Mainprice Texture Analysis of Geomaterials: A Challenge for EBSD

9:10 – 9:50 Plenary: Daniel Abou-Ras

Relationships of Microstructure and Device Performance in Thin-Film Solar Cells

9:50 – 10:10 Break

Session Deformation: Steels Cold Rolling

Rudy Wenk Recrystallization Advanced Processing Characterization

Chair(s) N Tsuji & R Ray S Vogel & L Miyagi H Sandim T Nelson S Singh & F Bachmann

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 10:10 – 10:40

S Suwas Texture, microtexture and mechanical properties of some Mn steels

K Kunze Quartz textures in rocks – progress in methodology, results and interpretations

A Leff Effect of recrystallization mechanisms on twin interconnectivity and corrosion resistance in FCC metals

M Hasegawa Texture Development of Alumina Coating Processed by Aerosol Deposition

B Hutchinson Evaluation of texture using laser-ultrasonics – application to steel processing

10:40 – 11:00

H Atsumi Effect of carbon addition on deformation texture of heavily cold rolled polycrystalline Fe-3%Si

L Lagoeiro The role of Dauphiné twinning on the development of quartz ribbons: implications for quartz superplasticity

G Shankar Evolution of recrystallization textures in Ni-Co alloys

T Mungole Transmission - EBSD on Ti/TiN Multilayer Thin-Films

S Singh Dynamical Simulations of Transmission Kikuchi Diffraction Patterns and Related Diffraction Modalities

11:00 – 11:20

T Morikawa Formation of High Angle Boundaries during Cold-rolling of Ti-added Ultra Low Carbon Steel

M Avalos Microstructure and microtexture characterization of avian eggshells

K-I Ikeda Effect of Sc and Zr Addition on Recrystallization Behavior and Texture formation in Al-Mg-Si alloy

P Chekhonin Inhomogeneities in strained epitaxial BaFe2As2 thin films

B Lan Texture determination using elastic waves for HCP and cubic materials

11:20 – 11:40

J Goulden Defining the mechanism for compaction of chondritic asteroids using EBSD-derived microtexture

NP Gurao Evolution of micro-texture and microstructure during conventional sintering of copper

S Pathak Strong, Ductile, and Thermally Stable Mg-Nb Nanolaminates

E Bouzy On-axis Transmission Kikuchi Diffraction in the SEM. Performances and Applications

11:40 – 12:00

A Pukenas Low-temperature EBSD investigations on a BaFe2As2 single crystal

NP Gurao Evolution of microstructure texture and mechanical behaviour of CoCuFeMnNi high entropy alloy subjected to high pressure torsion

K Thool Microtexture and Local Anelasticity Measurements: Uncharted Possibilities

12:00 – 13:30 Lunch: Garden Room

ICOTOM 18 TUESDAY 5

TUESDAY PM1

13:30 – 14:10 Plenary: Wolfgang Pantleon Evolving Deformation Structures: High-Resolution Reciprocal Space

Mapping and Orientation Distribution of Individual Grains

14:10 – 14:50 Plenary: Teryuki Tamaki Local Curvature Multi-Vertex Model on Grain Growth and Its Application

14:50 – 15:10 Break

Session Deformation: Ti Processing

Rudy Wenk Recrystallization Advanced Processing: ECAE

Characterization

Chair(s) S Mahesh M Kunz A Leff K Wierzbanowski F Ram & B Britton

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 15:10 – 15:40

N Tsuji Effect of Texture on Anisotropic Deformation Behaviors in Cold-rolled and Annealed Pure Ti

L Lutterotti 20 Years of Maud and the Rietveld Texture Analysis

Y Takayama Preferred orientation formation in Al-3mass%Mg subjected to shear deformation and subsequent annealing

M Janecek Influence of ECAP temperature on texture in pre-extruded AX41 magnesium alloy

D Dingley The contribution of EBSD to texture studies over the past 30 years

15:40 – 16:00

NP Gurao Effect of crystallographic texture on micro-mechanisms of deformation in monotonic and cyclic loading of titanium

S Vogel Texture Measurements by Neutron Time-of-flight Diffraction – a Powerful Tool Pioneered by Rudy Wenk

R Mathew Microstructure and Texture Evolution in Pulsed Electrodeposited Nanotwinned Copper

A Kustas Texture development in soft ferromagnetic Fe-Co-2V processed by Equal Channel Angular Extrusion (ECAE)

R Hielscher Denoising of EBSD Data

16:00 – 16:20

R Lim Microstructural Evolution of Ti-7Al Under Cyclic Loading

S Piazolo Principles of ice dynamics during crystal-plastic deformation: Linking texture, rheology and average grain size

R Ray Characteristics of Thin Cu Films Electrodeposited on Textured Ni Co Substrates

T Krajnak Texture evolution in extruded AX41 magnesium alloy severely deformed by ECAP via routes A, Bc and C

M Bieda Microstructural investigations of materials after severe plastic deformation by means of orientations mapping in TEM and SEM

16:20 – 16:40

F Wagner About the combined role of texture and grain size on hardening behavior of cp titanium sheets

R Suter Microscopic study of texture evolution under tensile strain: slip events in zirconium resolved in 3D

D Frandsen Fabricating Designed Crystallographic Textures through Heterogeneous Templated Grain Growth

H Paul The nucleation of cube grains during primary recrystallization of aluminium

S Ghodrat EBSD analysis of IF steels: comparison between 2D and 3D statistics

16:40 – 17:00 Break

ICOTOM 18 TUESDAY 6

TUESDAY PM2

Session Deformation: Steels Formability

Rudy Wenk Recrystallization Characterization

Chair(s) D Lindell T Ivankina & M Kunz A Leff F Ram & B Britton

Room Ballroom E Ballroom AB Ballroom C Entrada BC

17:00 – 17:20

JY Kang Effect of Texture on Mechanically Induced Martensitic Transformation in Duplex Stainless Steel

MD Jackson Authigenic Mineral Textures in Basaltic Tuff, Surtsey Volcano, Iceland

Y Li Relationship between Zener-Holloman Parameter, Grain Size Refinement, and Texture Evolution during Dynamic Recrystallization of AZ31B Mg…

F Bachmann Advances in 3D Grain Mapping with LabDCT

17:20 – 17:40

P Hou Role of microstructure, texture, and load partitioning in formability of TRIP steel and duplex stainless steel

R Bolmaro Study by XRD and EBSD of texture and microstructure of the eggs of Chelonoidis chilensis turtle

T Rodgers Incorporating Texture Models in Monte Carlo Simulations of Solidification

R Quey In-grain orientation spreads in deformed aluminium: 3DXRD-based measurements and finite element simulations

17:40 – 18:00

D Raabe DAMASK: Düsseldorf Advanced MAterial Simulation Kit for studying interlinked texture and plasticity in high strength steels

J Bernier Multigrain crystallography as a tool for texture analysis under high pressures and temperatures

A D Rollet Using High Energy Diffraction Microscopy (HEDM) to validate micromechanical fields calculated by FFT based method

18:00 – 19:00 Poster Session: North Lobby. See listing on pages 12-14

ICOTOM-18 TUESDAY POSTERS 7

POSTER SESSION

A: Advanced Materials & Processes A-1 Evolution of microstructure and texture in AA1100 during multi-axial diagonal forging J.-H. Shin1, M.-S. Kim1, S. C. Kwon2, S.-T. Kim2, S.-H. Lee3, S.-H. Yang3, S. Lee3, S.-H. Choi1 and H.-T. Jeong2 1Department of Printed Electronics Engineering, Sunchon National University, Sunchon 57922, Republic of Korea. 2Department of Advanced Metal and Materials Engineering, Gangneung-Wonju National University, Gangneung 25457, Republic of Korea. 3Agency for Defense Development, Yuseong-si, Daejeon 34186, Republic of Korea.

A-2 Development of micro fibril textures in melt-spun polyamide-6 fibers by transversal compression N. Wirch1, R. Ghadimi2, T. Vad3 and T.E. Weirich1,4 1Central Facility for Electron Microscopy (GFE), RWTH Aachen University, Aachen, Germany. 2Tietz Video and Image Processing Systems GmbH, Gauting, Germany. 3Institute for Textile Engineering (ITA), RWTH Aachen University, Aachen, Germany. 4Institute of Crystallography (IFK), RWTH Aachen University, Aachen, Germany.

A-3 Microstructure and Texture of Titanium grade 2 after ECAP Processing M. Wroński1, K. Wierzbanowski1, R. Z. Valiev2,3, J. Kawałko4, K. Sztwiertnia4 and E. Szyfner1

1AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, 30-059 Kraków, Poland. 2Institute of Physics of Advanced Materials, Ufa State Aviation Technical University, 450000 Ufa, Russian Federation. 3Laboratory for Mechanics of Bulk Nanomaterials, Saint Petersburg State University, Peterhof, Saint Petersburg, 198504, Russia. 4Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 30-059 Kraków, Poland

A-4 Texture, microstructure and mechanical properties evolution in Fe-(x=36 and 48 wt.%) Ni alloy after accumulative roll bonding S. Boudekhani-Abbas1, K. Tirsatine1, H. Azzeddine1,2, B. Alili1, A.L. Helbert3, F. Brisset3, T. Baudin3, D. Bradai1 1Faculty of Physics, University of Sciences and Technology Houari Boumediene, BP 32 El-Alia, 16111, Algiers, Algeria. 2 Departments of Physics, University of M’sila, Algeria. 3 ICMMO, SP2M, Univ. Paris-Sud, Université Paris-Saclay, UMR CNRS 8182, 91405 Orsay Cedex, France

A-5 Characterization of Fe-Co soft ferromagnetic alloys processed by laser engineered net shaping (LENS) Andrew B. Kustas, Kyle L. Johnson, Shaun R. Whetten, Dave M. Keicher, Mark A. Rodriguez, Daryl J. Dagel, Joseph R. Michael, Nicolas Argibay, Don F. Susan Materials Science and Engineering Center, Sandia National Laboratories, Albuquerque, NM, 87123

A-6 directionally solidified non-modulated Ni54Mn24Ga22 alloys in a gradient magnetic field Long Houa, Yanchao Daia, Zongbin Lib, Yikun Zhanga, Zhongming Rena, Xi Lia,* aState Key Laboratory of Advanced Special Steels, Shanghai University, Shanghai 200072, China bKey Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China

B: Grain Boundaries B-1 Obtaining 5D Grain Boundary Character from Surface EBSD using Band Intensity Profiles A. Amalaraj, J. Christensen, O.K. Johnson, E.R. Homer, D.T. Fullwood Brigham Young University, Provo, USA.

B-2 Effect of grain boundary engineering on the corrosion behavior of Hastelloy C-276 J. Vijay Bharadwaj1, B. Shakthipriya1 and V. Subramanya Sarma1 1Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, India.

B-3 Microcrack Initiation and its Propagation in Cu metal films on a flexible PI substrate during cyclic-bend testing Atanu Bag, Ki-Seong Park and Shi-Hoon Choi Department of Printed Electronics Engineering, Sunchon National University, Suncheon Jeonnam, Republic of Korea

C: Characterization C-1 Texture Analysis using High Energy Material Science Beam Line (HEMS)@Petra III/Hasylab-Hamburg H.-G. Brokmeier1, Z.Y. Zhong2, M.Z. Salih1, N. Al-Hamdany1, S. Sanamar1, X. Zhou1, R. Bolmaro3, N. Schell4 1Inst. of Materials Science and Engineering, TU Clausthal, Clausthal-Zellerfeld, Germany. 2Chinese Academy of Applied Physics, Mianyang, PR China,3 Inst. de Fisica Rosario, IFIR/CONICET, Rosario, Argentina,4 Helmholtz-Zentrum Geesthacht, GEMS-Outstation DESY, Hamburg, Germany

C-2 Comparison of preferred orientation of austenite and ferrite phases of duplex steel with rolled single phase austenitic and ferritic steel J. Capek1, M. Cernik2 and N. Ganev1 1Czech Technical University in Prague, Prague, Czech Republic. 2U. S. Steel Kosice, Kosice, Slovakia.

C-3 Quantitative Fiber Diffraction: from polymers to composites L. Lutterotti, L. Fambri and M. Bortolotti Department of Industrial Engineering, University of Trento, Trento, Italy.

C-4 Practical applications of nondestructive texture measurement methods M. Sepsi, M. Benke and V. Mertinger University of Miskolc, Miskolc, Hungary.

C-5 Rotation angle optimization for texture measurement using TOF neutron diffraction S. Takajo1, 2 and S. C. Vogel1 1Los Alamos National Laboratory, Los Alamos, USA. 2JFE Steel Corporation, Kurashiki, Japan.

ICOTOM-18 TUESDAY POSTERS 8

C-6 ANDES: a multi-purpose neutron diffractometer for the RA10 M.A. Vicente Alvarez1, J.R. Santisteban1, A. Beceyro1, I. Marquez1, S. Gomez, L. Monteros, S. Pincin, A. Glucksberg, A. Coleff2 1Neutron Physics Department, Centro Atómico Bariloche, CNEA. 2Mechancial Division, Centro Atómico Bariloche, CNEA

C-7 Progress on the Development of Texture Analysis Capabilities at the HFIR and SNS at ORNL C.M. Fancher1, J. Bunn1, J. Einhorn2, C. Hoffmann, M.D. Frontzek, and E.A. Payzant1 1Oak Ridge National Laboratory, Oak Ridge, USA. 2University of Virginia, Charlottesville, USA.

D: Deformation D-1 Refining Statistical Magnesium Twinning Models via Machine Learning A.D. Orme, D.T. Fullwood, I. Chelladurai, C. Giraud-Carrier, T. Colton Brigham Young University, Provo, USA.

D-2 Simulation for texture formation of both face-centered-cubic metals and body-centered-cubic ones based on rotational symmetry among X[100],Y[010] and Z[001] principal axes H. Masui Teikyo University, Utsunomiya, Japan

D-3 Texture Changes of Electromagnetic Ferritic Stainless Steels by Compressive Deformation at High temperatures Y. Onuki1, S. Sato1, M. Uchida1, T. Naruse2, Y. Kim2, T. Ebata2, S. Fujieda3 and S. Suzuki3 1Ibaraki University, Ibaraki, Japan. 2Tohoku Steel Co., Ltd., Miyagi, Japan. 3Tohoku University, Sendai, Japan.

D-4 Texture evolution of low carbon steel wires resulted from prior drawing process Athanasios Vazdirvanidis1, George Pantazopoulos1, Marianna Katsivarda2, Avraam Mastorakis3 1ELKEME, Hellenic Research Centre for Metals S.A, 2National Technical University of Athens (N.T.U.A.) - School of Mining & Metallurgical Engineering, 3SIDENOR S.A.

D-5 The effect of damping capacity on twinned AZ31 magnesium alloy after heat treatment J.H. Kwak1, J.H. Choi1 C.Y. Kang1 and K.H. Kim1 1Pukyong National University, Busan, Republic of Korea.

D-6 Texture formation behavior during high-temperature deformation in M1 magnesium alloy K.J. Lee, M.S. Park, J.H Choi and K.H Kim Pukyong National University, Busan, Republic of Korea.

D-7 Deformation Behavior of Commercially Pure Titanium (Grade-2) under Uniaxial Compression Devesh Kumar Chouhan, Sudeep Kumar Sahoo, Somjeet Biswas Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, West Bengal-721301, India

N: Numerical Methods N-1 Texture Visualization Using Neo-Eulerian Rotation Representations P.G. Callahan1, M. Echlin1, T.M. Pollock1, S. Singh2 and M. De Graef2 1UC Santa Barbara, Santa Barbara, USA. 2Carnegie Mellon University, Pittsburgh, USA.R-1 Recrystallization Texture Evolution of Cold Rolled and Asymmetrically Warm Rolled Austenitic Stainless Steel Sheets

R: Recrystallization R-1 Recrystallization Texture Evolution of Cold Rolled and Asymmetrically Warm Rolled Austenitic Stainless Steel Sheets S. Umehara1, H. Inoue1 and J. Hamada2 1Osaka Prefecture University, Sakai, Japan. 2Nippon Steel & Sumikin Stainless Steel Corporation, Hikari, Japan.

R-2 Effect of Y contents on microstructure and texture evolutions in grain-oriented silicon steel C.S. Park, H.D. Joo, K.S. Han, J.K. Kim and J.T. Park

Steel Product Ⅱ Research Group, POSCO

Technical Research Laboratories, Pohang, Korea.

R-3 The effect of an intermediate heat treatment during thermomechanical controlled processing on recrystallization and subsequent deformation-induced ferrite transformation textures in microalloyed steels P. Gong, B.P. Wynne, W.M. Rainforth Department of Materials Science and Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, S1 3JD, UK

T: Transformations T-1 Effect of strain-induced martensitic transformation on texture evolution in cold-rolled Co-Cr alloys S. Sato1, M. Nakagawa1, Y. Onuki2, K. Yamanaka3, M. Mori4, A. Hoshikawa2, T. Ishigaki2 and A. Chiba3 1Graduate School of Science and Engineering, Ibaraki University, Hitachi, Japan. 2Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Japan. 3Institute for Materials Research, Tohoku University, Sendai, Japan. 4Department of Materials and Environmental Engineering, National Institute of Technology, Sendai College, Natori, Japan.

T-2 Characterization of the Factors Influencing Retained Austenite Transformation in Q&P Steels via EBSD Analysis D. Adams¹, D. Fullwood¹, J. Cramer¹, S. Irfan¹, H. Evanson¹, T. Mathis¹, S. Cluff¹, M. Miles¹, E. Homer¹, T. Brown², R. Mishra², and B. Kubic² ¹Brigham Young University, Provo, USA. ²General Motors, Warren, USA.

W: Rudy Wenk W-1 Texture and fracture anisotropy in shales deformed in a deformation DIA Jeff Gay1, Waruntorn Kanitpanyacharoen2, Michael Jugle1, Julien Gasc3-4 Tony Yu4, Yanbin Wang4, and Lowell Miyagi1 1Department of Geology and Geophysics, University of Utah, Salt Lake City, UT U.S.A. 2Department of Geology, Chulalongkorn University, Bangkok Thailand. 3Laboratoire de Géologie, École Normale Supérieure-CNRS, UMR8538, Paris France. 4Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL U.S.A.

W-2 In situ texture measurements at high-pressure and high temperature using double-sided laser heating in a radial diffraction diamond anvil cell at ALS beamline 12.2.2 M. Kunz1, J. Yan2, Alastair MacDowell1, Lowell Miyagi3 and H.R. Wenk4 1Lawrence Berkeley Lab, Berkeley, California. 2UC Santa Cruz, Santa Cruz, California. 3University of Utah, Salt Lake City, USA. 4UC Berkeley, Berkeley, California.

ICOTOM-18 TUESDAY POSTERS 9

W-3 CPO patterns of an upper crustal shear zone – examples from the Lancinha Fault System, southern Brazil T. Conte1, G.C.G. Cavalcante1, L.E. Lagoeiro1, C.S. Silveira1, K.T. Pesch1, and R. Santos1. 1UFPR – Universidade Federal do Paraná, Curitiba, Brazil.

W-4 Microscale strain partitioning during high-temperature deformation of plagioclase: an example from gabbro-norite of the Barro Alto Complex, Brazil central C.S Silveira¹, L.E. Lagoeiro¹, G.C.G. Cavalcante¹, P.F. Barbosa², F.O. Ferreira³, T. Conte¹, R. Santos¹ M.T.F. Suita4 ¹Universidade Federal do Paraná, Curitiba, Brazil; ²Univesidade de Brasília, Brasília, Brazil;³ Universität Bayreuth, Bayreuth, Germany ; 4Universidade Federal de Ouro Preto, Ouro Preto, Brazil.

W-5 Application of the Elasto-Viscoplastic Self Consistent (EVPSC) code to modeling texture and lattice strain evolution in periclase

F. Lin1, N. Hilairet2, S. Merkel2, J. Immoor3, H. Marquardt3, C. Tomé4 and L. Miyagi1 1Department of Geology and Geophysics, University of Utah, Salt Lake City, 84112, USA. 2Unité Matériaux et Transformations, Université Lille 1 - CNRS - ENSCL, Villeneuve d'Ascq, France. 3Bavarian Research Institute of Experimental Geochemistry and Geophysics, University Bayreuth, 95440 Bayreuth, Germany. 4Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA

W-6 Deformation of two-phase polycrystals under high pressures: effect of phase proportions on in-situ textures and stress partitionning in olivine + antigorite N. Hilairet1, T. Ferrand2, P. Raterron1, S. Merkel1, A. Schubnel2, J. Guignard3*, C. Langrand1, W. Crichton3 1CNRS - Université de Lille - ENSCL, 59000 Lille, France. 2CNRS - ENS, 75005 Paris, France. 3European Synchrotron Radiation Facility, 38000 Grenoble, France. *now at Observatoire Midi-Pyrenées, 31400 Toulouse, France

ICOTOM 18 WEDNESDAY 10

WEDNESDAY AM 8:00 Registration/Info Desk Open

8:00 - 8:30 Video Presentation: Peter Bunge

8:30 - 8:50 Bunge Award Presentation

8:50 - 9:30 Awardee Presentation

9:30-9:40 Break

Session Deformation: Al Rudy Wenk Phase Trans. Advanced Proc.: ARB Characterization

Chair(s) G Winther & S. Suwas L Miyagi & P Burnley L Kestens & T Tomida M Hasegawa R Bolmaro & R McCabe

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 9:40 – 10:10

K Marthinsen Evolution of deformation texture during flat profile extrusions and its understanding by FEM and crystal plasticity modelling

C Tomé A trip with Rudy: from calcite to quartz

T Tomida Variant selection mechanisms and quantitative prediction of transformation textures in steel

K Verstraete Study of the texture developed by ARB and CARB processes on an AA5754/AA6061 composite

T Ruggles Concurrent in situ HREBSD and HRDIC analysis of an AlCu oligocrystal using selectively electron transparent microstamping

10:10 – 10:30

B Diak Rolling Texture Development in Aluminum-Zinc Solid Solutions

R Lebensohn 20 years inspired by Rudy Wenk’s challenges to model texture, microstructure and anisotropy of geomaterials

S-J Park β-Mn transformation and orientation relationship in austenite-based FeMnAlC low-density steel

DJ Savage Texture evolution in accumulative rolled bonded Mg-Nb composites from polycrystal to single crystal layers

D Kim Effect of grain orientation on hydrogen embrittlement of high manganese steel

10:30 – 10:50

M Kobayashi Investigation of inhomogeneous deformation and microstructure during cold rolling in Al-Mg alloys by using 3D marker tracking method

W Skrotzki Texture formation in ionic crystals with rock salt structure

C Ranger Austenite Reconstruction Elucidates Prior Grain Size Dependence of Toughness in a Low Alloy Steel

H Inoue Texture and Microstructure of Laser Butt-Welded AZ61Mg/Ti clad sheet

T Sano 3D EBSD Characterization of Al5083 Spall Damage

10:50 – 11:10

NP Gurao New insights on modeling deformation texture and yield strength anisotropy in age hardenable Al-Mg-Si alloys

N Barton A Method for Including Diffusive Effects in Texture Evolution

L Kestens Variant Selection at Parent Phase Grain Boundary Nucleation

During -to- Phase Transformation in Low Carbon Steel

K Tanaka Relationship between Initial Hydrogen Absorption Properties and Microstructures of Mg/Cu Super-Laminate Composites with Different ARB Cycles

S Saimoto Crystal Orientation Examination of Patterns Formed by Micro-indentation of Cube-textured Aluminum Foil Using SAXS and Temperature Changes

11:10 – 11:30

W Tayon Impact of Texture on Anisotropy and Delamination Cracking in Al-Li Alloys

L Morales Fabric Transitions in Quartz via Visco-Plastic Self-Consistent Modelling: Axial Compression and Simple Shear under evolving Strain

S Cluff Crystallographic Reconstruction of Parent Austenite Twin Boundaries in a Lathe Ferritic Steel

J Scharnweber Influence of Texture on Layer stability in Ti/Al ARB Composites

R Bolmaro Study of the microstructure of a cold rolled interstitial free steel through X-Ray Diffraction and EBSD

11:30 – 11:50

S Merkel The Androgynous Twins of Zinc

T Nguyen-Minh Reconstruction of austenite microstructures in steels by global optimization of misorientation functions

M Knezevic Deformation behavior and strength of bulk Zr/Nb nanolayered composites

A Godfrey (invited) Characterization of local plastic strain during deformation from EBSD data – limitations and possibilities

12:45-21:00 Excursion to Zion National Park & Conference Banquet

ICOTOM 18 WEDNESDAY 11

WEDNESDAY PM EXCURSION TO ZION NATIONAL PARK & BANQUET On Wednesday afternoon we will visit Zion National Park and have our Conference Banquet in Springdale at the mouth of Zion

Canyon. Buses will depart for Zion NP from the Hotels and the Dixie Center. The buses will arrive at the Zion NP Lodge at

approximately 2:00PM. From the Zion Lodge you will be able to explore Zion canyon.

Southwest Adventure Tours will have guides who will lead interpretative walks/hikes to the following trails: Emerald Pools, Weeping

Wall, River Walk/Zions Narrows, Kayenta Trail. Our guides will be arranged in groups of Active (Red Lollypop Stick) (3 to 5 mile hike),

Moderate (Blue Lollypop Stick) (1 to 3 mile hike), and Scenic (Green Lollypop Stick) (less than 1 mile of walking). They will organize

on the front lawn of the Lodge in groups.

Zion National Park has shuttle busses arriving at 9 stops in Zion National Park every 7 to 15 minutes. This is the only way to move

around the park other than walking. Stop 5 is Zion Lodge. Stop 1 is at the Visitors Center and if you wish to stroll around the small

town of Springdale and the souvenir shops you can use this stop.

All guests are free to explore the park on their own. For those not interested in hiking or walking on the trails with our guides, you

can just ride the shuttle up and down the canyon for a few hours and enjoy the beautiful views or stop and hike on your own.

Please use the information on this link to plan what you would like to see and do in Zion National Park.

https://www.nps.gov/zion/learn/news/upload/tear_sheet_9-30-web-saa.pdf. This document has basic information about hikes and

walks that are available in the park, a basic park map, shuttle stop information, and a few other details to help you plan ahead.

At 5:30 PM to 6:30 PM the busses will depart from Zion Lodge to Switchback Grill where the conference banquet will be held. Each

bus will depart when full. You are not required to ride on the same bus you came from St George on to travel from Zion Lodge to the

Switchback Grill.

The buses will depart at 8:00 PM from the Switchback Grill and arrive at approximately 9:00 PM at the hotels and Dixie Center.

Some notes from Utah native Stuart Wright:

One of the famous hikes in all of America’s southwest canyon country is the Zion Narrows. You can hike about a mile up the canyon on a paved trail (Riverside Trail) but then the canyon narrows and you have to get wet to go any further. There won’t be enough time for you to hike all the way to the top of the narrows and out of the canyon but a hike up the river for even an hour is a great experience. You will get wet hiking the narrows and a hiking staff or trekking pole is helpful to navigate the slippery rocks in the riverbed. While there are boots specifically designed for canyoneering I usually just wear an old pair of tennis shoes. I do not recommend hiking in sandals.

If you do choose to do this hike you will want to bring an extra pair of shoes, socks and pants to change into after the hike as well as a sweatshirt or coat as the water is cold and the canyon is always cool even on hot summer days. You can rent trekking poles for this hike from the guide for $5 per pole. Payment can be made in cash to the guide.

Another famous hike in Zion is Angel’s landing which is very steep. The final portion of the trail is a narrow ridge line with sheer drops offs of over 1000 feet on either side. But you are rewarded with some amazing views. It is a very strenuous trail and it would be extremely difficult to do in the few hours we have in the park before dinner (and dark). If you want to do this trail I recommend coming a day early to the conference or staying a day later. You could contact Southwest Adventure Tours for transportation options.

ICOTOM 18 THURSDAY 12

THURSDAY AM 8:00 Registration/Info Desk Open

8:30 – 9:10 Plenary: Lionel Germain Advanced Parent Reconstruction: An Efficient Tool to Optimize TMTs by a

Better Control of the Parent and Subsequent Inherited Microtexture

9:10-9:50 Plenary: Chris Schuh The Texture Between the Grains: Statistics of Grain Boundaries and Grain

Boundary Networks

9:50-10:10 Break

Session Deformation: Advanced Materials

Deformation: Steels Hot Rolling

Phase Transformations Advanced Processing: Additive Manufacture

Grain Boundaries

Chair(s) P Van Houtte & F Wagner

B Hutchinson & W Pantleon

Y Zhang T Nelson S Patala

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 10:10 – 10:40

KVM Krishna Role of crystal orientation on deformation of Zr: A Molecular dynamics study

D Lindell Texture evolution of duplex stainless steel UNS S32205 under hot working conditions

P Yang Analysis of texture memory, surface-effect-induced transformation texture and variant selection in low graded electrical steels

A Rollett Anisotropy and Microstructure in 3D Printed IN 718

G Rohrer Grain Boundary Texture, Energy, and Curvature as a Function of Lattice Misorientation and Grain Boundary Plane Orientation

10:40 – 11:00

M Ito Texture evolution modeling of Ni alloys by crystal plasticity including twinning

T Toyoda Texture evolution after dynamic recrystallization in Fe-Mn-Si steel

A Tiamiyu Texture memory in AISI 321 austenitic stainless steel

S Vogel In-situ Investigation of Microstructure Evolution during Annealing in Ti-6Al4V Alloy Produced by Additive Manufacturing

E Homer Grain Boundary Plane Structure-Property Relationships and Fundamental Zones

11:00 – 11:20

JP Escobedo Texture evolution in clock-rolled Zr during dynamic extrusion

S Suzuki Texture Changes of Electromagnetic Ferritic Stainless Steels by Compressive Deformation at High temperatures

MA Vincent Alvarez Crystallographic Texture and Microstructural changes in a weld of two Zry-4 plates: Variant selection Model

A Rollett Effect of Microstructure and Texture on the Elasto-viscoplastic Deformation of Dual Phase Titanium Structures

N Mavrikakis Segregation Affecting the Evolution of Primary Recrystallization Textures in a Ternary Fe-Si-Sn Alloy

11:20 – 11:40

B Kania Texture as a guideline for XRD residual stress investigation

C-T Nguyen The effect of cold work on the texture of a Zirconium alloy after fast β-cycling

C Goulas Texture development in steel components produced by Wire Arc Additive Manufacturing

C Kurniawan Inferring Grain Boundary Structure-Property Models from the Effective Properties of Polycrystals via Inverse Problem Theory

11:40 – 12:00

Y Dai Martensitic transformation, twin boundary and phase interface mobility of directionally solidified Ni-Mn-Ga alloys during compression by EBSD tracing

C Daniel Texture Evolution during Hot-Rolling of Dual Phase Zirconium Alloys

S Ghorbanpour Role of texture in tensile, compressive, cyclic, and fracture behavior of direct metal laser sintered Inconel 718

J Bair Mechanisms of Grain

Growth in -7 and -9 Grain Boundaries with Mixed Mobility Trends

12:00 – 13:30 Lunch Garden Room

ICOTOM 18 THURSDAY 13

THURSDAY PM1

13:30 – 14:10 Plenary: Sivasambu Mahesh A Model of Grain Fragmentation and Microtexture Evolution During

Plastic Deformation

14:10 – 14:50

Plenary: Brad Wynne & Matthew Thomas The Evolution and Quantification of Preferred

Crystallographic Orientations in Wrought Titanium Alloys Using Traditional and Emerging

Technologies

14:50 – 15:10 Break

Session Deformation: Modelling

Deformation: Torsion Phase Transformations Advanced Processing: FSW

Grain Boundaries

Chair(s) H Garmestani L Toth L Germain S Biswas E Homer

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 15:10 – 15:40

G Winther Measured resolved shear stresses and active slip systems in austenitic steel

I Samajdar Microstructural Engineering in Pearlitic Steel Wires

Y Zhang Formation of microtexture induced by β to α transformation in a metastable β Ti alloy

T Nelson Texture evolution in flash and weld zone of friction welded 718 superalloy

R Ray Role of CSL Boundaries During Cold Rolling and Annealing of an Interstitial Free Steel

15:40 – 16:00

NY Juul Comparison of measured lattice rotations of individual grains with crystal plasticity simulations

S Naghdy Reciprocal effect of texture evolution and grain fragmentation during High Pressure Torsion processing

D Solas Variant selection in alpha/beta Ti alloy

J Zhang Using EBSD in the characterization of heterogeneous microstructure created in high speed FSW Al…

S Patala The Representation of Grain Boundary Texture Using Hyperspherical Harmonics

16:00 – 16:20

E Zepeda-Alarcon Texture Development in Two-Phase Mineral Aggregates: Modeling Plastic Deformation with Finite Element Methods

H-G Brokmeier Texture gradient in extruded Mg-alloys versus extruded Mg-Al composites

S Niezgoda Probabilistic methodology for analyzing and reconstructing parent microstructures from EBSD maps of transformation products

R Fonda Friction Stir Weld Textures and their Implications on 3D Material Flow

S Xia Grain orientation statistics of grain-clusters and the propensity of multiple-twinning during grain boundary engineering

16:20 – 16:40

P Van Houtte Statistical models for deformation texture prediction using vortex-type accommodation of local strain…

M Latypov Hierarchical data-driven models for texture evolution in advanced multiphase materials

S Roy Orientation dependent spheroidization response and α-phase texture evolution during… sub β-transus annealing of Ti…

FC Liu Texture evolution during friction stir welding of austenite stainless steel

E Homer, S Patala, G Rohrer, C Schuh & D Field Panel Discussion: Current status and future directions of grain boundary science and engineering 16:40-

16:50

16:40 - 17:00 Break

ICOTOM 18 THURSDAY 14

THURSDAY PM2

Session Deformation: Modelling

Deformation: Damage & Fracture

Numerical Methods Adv. Processing: Asymmetric Rolling

Grain Boundaries

Chair(s) R Lebensohn Y Wang M Knezevic H-G Brokmeier G Rohrer

Room Ballroom E Ballroom AB Ballroom C Sunbrook AB Entrada BC

Invited 17:00 – 17:30

L Toth Revealing deformation heterogeneity from texture modeling

S Suzuki Mechanical damage evaluation by using EBSD measurement

A Morawiec Parameterization of rotations in reference frames with redundant crystallographic axes

A Kliauga Experimental and Numeric Analysis of Strain and Texture of Asymmetric Rolled AA1050 Al

D Field Excess Dislocation Density near Boundaries as a Function of GB Texture

17:30 – 17:50

J Sidor Texture evolution in Al alloys: crystal plasticity and continuum mechanics based modelling…

B Shakerifard Damage initiation mechanisms under static and dynamic loading conditions in bainitic steels

A Creuziger Systematic bias effects on phase fraction measurement due to texture

S Dhinwal Texture and microstructure development in warm asymmetric rolled extra low carbon steel

L Hansen Characterizing GB Dislocation Interactions though HR-EBSD and Machine Learning

17:50 – 18:10

NP Gurao Crystal plasticity simulations of rolling texture evolution in two phase tungsten heavy alloy

C Kantzos Evaluating the Role of Texture on Surface Roughness Induced Stress Concentrations

T Critchfield Comparison of Representative Volume Elements for Grain Boundary Networks and Textures

K Wierzbanowski Modification of Texture and Microstructure of Polycrystalline Copper after Asymmetric Rolling

H Pirgazi Study of GB Character distribution in Annealed and Deformed Al by 3D EBSD

18:10 – 18:30

W Mao Intergranular interactions of metals during deformation and corresponding prediction of deformation textures

S Wright EBSD Observations of Fatigue Crack Propagation in Ni Alloy

KS Sridhar Quantification of Uncertainties in Pole Figure Analysis

M O'Brien Characterization of Grain Boundary Cracking Susceptibility in Pipeline Steels using EBSD

ICOTOM-18 FRIDAY 15

FRIDAY 8:00 Registration/Info Desk Open

8:30 – 9:10 Plenary: Yadong Wang Grain-Orientation-Dependent Fatigue Damage in Polycrystalline Materials

9:10 – 9:50 Plenary: Sandra Piazolo Making and Breaking of Minerals, Rocks and Planets: A Textural Perspective

9:50 – 10:10 Break

Session Deformation: Steel Processing

Recrystallization Numerical Methods Advanced Processing: Forging & Extrusion

Advanced Engineering

Chair(s) K Marthinsen & R Fonda

R McCabe O Johnson H Inoue T Rollett

Room Ballroom E Garden Room Ballroom C Sunbrook AB Entrada BC

Invited 10:10 – 10:40

A Kaijalainen Development of crystallographic texture under shear strain in ultrahigh-strength strip steels

Y He Effect of Annealing Temperature on the Texture and Magnetic Barkhausen Noise of a Non-Oriented Electrical Steel (0.88 wt% Si) after Inclined Cold Rolling

M Knezevic Spectral database constitutive representation within finite element and spectral micromechanical solvers for computationally efficient crystal plasticity modelling

S Biswas Microstructure and texture evolution during modified multi-axial forging of Magnesium alloy Mg–3Al–0.4Mn

H Garmestani Material Forensics

10:40 – 11:00

S Vogel Effect of Processing Methods on Texture Evolution and Recrystallization Studies on 14YWT Nanostructured Ferritic Alloys

F Cruz-Gandarilla Study of the recrystallization kinetics in Fe3%Si steels during the 1st recrystallization using misorientation derived parameters (EBSD) in the CGO process

S Singh A Model Based Iterative Reconstruction Algorithm for Pole Figure Inversion

X Bai Characterization of microstructure and texture in 6013 aluminum alloy after large strain extrusion machining process

K Cho EBSD Analysis of Pt-20Ir Wire as Lead Conductor in Implantable Medical Device

11:00 – 11:20

S Takajo Spatially resolved texture and microstructure evolution of gas gun deformed SUS304 steel using neutron diffraction

M Mehdi Texture Evolution of a 3.2 wt% Si Non-Oriented Electrical Steel during Hot Band Annealing

M Zecevic Mean-field modeling of recrystallization textures

M Jamalian Microstructure and Texture Evolution of Magnesium alloy after Shear Assisted Processing and Extrusion (ShAPE).

A Schwedt Recrystallization and crystal growth phenomena during Rolling Contact Fatigue and White Etching Crack formation of AISI 52100 bearings

11:20 – 11:40

E Vakhitova Texture Evolution Analysis in Oxide Dispersion Strengthened Ferritic Steel Transformed by a Tube Pilgering Process

R Suehiro Effect of solute Sn on the evolution of primary recrystallization texture in 3% Si-Fe

H-G Brokmeier Estimation of the orientation distribution function using incomplete sets of pole figures data

J Chen Texture development in Al-Mg-Si alloys extruded through porthole die

D Guan Individual effect of recrystallization nucleation sites on texture weakening in a magnesium alloy

11:40 – 12:00

R Bolmaro EBSD analysis of orientation gradients at grain boundaries

T Kataoka Influence of cold rolling reduction on secondary recrystallization textures in Fe-3%Si sheet

S Niezgoda Application of the symmetrized Bingham distribution and other parametric distributions for the modelling of texture uncertainty

A Jarzębska Synergic effect of Mg addition and hydrostatic extrusion on microstructure and texture of biodegradable low-alloyed zinc

E Hoar Materials-Affected Manufacturing: Inverse Model for the Simulation of Texture Evolution in Ti64 through Turning

12:00 – 12:30 Closing Remarks – Garden Room

ABSTRACTS

ABSTRACTS MONDAY AM - PLENARIES 17

MONDAY AM PLENARY SESSION

Textures studied at near atomic scale D. Raabe, M. Herbig, B. Gault , A. Stoffers, Y. Chang, A.J. Breen, L. Morsdorf, M. Yao, C.H. Liebscher, C. Scheu and G. Dehm Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany.

Crystallographic texture phenomena in materials occur and matter over practically all length and time scales. This lecture presents recent insights

on texture effects at the near atomic scale. Specific attention is placed on such phenomena where the link between crystallographic texture and

local compositional effects plays a role. Corresponding experiments have been conducted using correlative electron microscopy in conjunction with

atom probe tomography on the one hand and atom probe crystallography on the other hand. In the former case joint crystallographic and chemical

information is obtained by conducting electron microscopy directly on atom probe tips prior to field evaporation and mass-to-charge spectroscopy.

In the latter case crystallographic analysis is conducted directly on atom probe data, exploiting field desorption and evaporation anisotropy effects.

Examples are presented from different functional and structural materials such as solar cells, hydrides and steels.

How textures helped us understand deformation in the Earth H.-R. Wenk Department of Earth and Planetary Science, University of California, Berkeley, USA.

The most visible impact of modern texture analysis has been in materials science, improving the quality of metallic alloys and epitaxial films. It has

also added tremendously to advance our understanding of deformation processes in the Earth. The term “texture” was first introduced in the 1833

textbook by the Belgian geologist D’Omalius d’Halloy to describe preferred orientation of crystals in rocks. With new analytical methods such as

neutron and synchrotron X-ray diffraction as well as EBSD we can now quantify textures in a way that was unthinkable 20 years ago and, advancing

sophisticated modeling methods, crystal alignment can now be predicted for a wide range of conditions, including plasticity, recrystallization, even

for complex polyphase materials such as most rocks. An example is the rock slate, composed mainly of quartz and mica. Texture analysis revealed a

texture strength in excess of 195 m.r.d., a new record, and this is not close to a single crystal but a very fine-grained polyphase aggregate. Similar

rocks that cover large volumes in sedimentary basins are shales with weaker but significant textures, creating macroscopic anisotropy that is highly

significant for seismic exploration of hydrocarbon deposits and has raised a lot of interest. In many ways the most fascinating application is the

deep Earth where geophysicists have documented significant anisotropy for propagation of seismic waves, particularly in the upper mantle (~100-

250 km), the lowermost mantle (~2800-2900 km) and the innermost core (~5000-6300 km). Geodynamicists suggest large-scale convection in much

of the deep Earth, with very significant strain. If we know deformation mechanisms of the mineral components, which we can approach with

ultrahigh pressure deformation experiments (such as diamond-anvil cells) or theoretical models, then we can predict crystal alignment and apply it

to the geodynamic strain evolution. This has been done for the upper mantle where the main phase is olivine Mg2SiO4, to the lowermost mantle

with a mixture of MgSiO3 “postperovskite” and MgO periclase, and the inner core composed of hcp iron. Some examples will be shown that

demonstrate that alignment of crystals during convection is the likely cause of seismic anisotropy. Such research that links microscopic processes at

the crystal scale with large macroscopic properties at the 1000 km scale, has only become possible through close collaborative interaction of

geoscientists and materials scientist, and meetings such as ICOTOM have been invaluable in establishing such contacts.

ABSTRACTS MONDAY AM - DEFORMATION 18

Symposium D: Deformation Textures Session: Magnesium

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Comparison of in-situ tension and in-situ compression behavior of Mg-AZ80 H.-G. Brokmeier1, N. Al-Hamdany1, R. Bolmaro2, A. Roatta2, E. Benatti2, M. Avalos2, V. Ventzke3, N. Schell4 1Inst. of Materials Science and Engineering, TU Clausthal, Clausthal-Zellerfeld, Germany. 2 Inst. de Fisica Rosario, IFIR/CONICET, Rosario, Argentin. 3 Helmholtz-Zentrum Geesthacht, Geesthacht, Germany. 4 Helmholtz-Zentrum Geesthacht, GEMS-Outstation DESY, Hamburg, Germany

Tension-compression behavior of Mg and Mg-alloys is longtime

known but still of basic interest. The present investigation was

performed with a rectangular extruded bar with an initial texture

composed of <0001> fibre //ND, <10.10>fibre // ED, {0001}<10-10>

ideal component and {11-20}<10-10>. Compression tests were made

with compression axis //ND, //TD and // ED of the extruded bar,

while tension was done with samples of ED, TD and 45° oriented

samples. In- situ experiments were carried out with high energy X-

rays for fast measurements to follow texture evolution as well as

lattice strain and microstrain evolution. The beamline HEMS@Petra

III was used with about 87keV. In all cases one can see the strong

influence of the initial texture on the texture evolution and,

particularly for tension, the different behavior of initial texture

components on reactivity during plastic deformation is more

evident. The compression texture of Mg shows an orientation of the

<0002> // to the compression axis with different scatter and

different texture sharpness. MgAZ80 shows only a moderate texture

sharpness compared to other alloys or commercially pure Mg.

Tensile load leads to a double pole in the basal pole figure with tilt of

15° in ±TD. Texture sharpness decreases in all cases of tension.

During in situ loading the typical stress strain curve was documented

and, in parallel, up to 250 diffraction patterns were collected. Due to

the high synchrotron energy, the wavelength is very short and

consequently complete Debye-Scherrer rings were obtained. Lattice

strain behavior will be correlated on one hand related to the texture

evolution and on the other hand as diffraction pattern parallel and

perpendicular to the loading direction.

The synchrotron experiments were accompanied by texture

simulations, bulk texture analysis using neutron diffraction and EBSD

investigations. Besides intensity pole figures (crystallographic

texture) we also present line broadening pole figures (microstrain).

[1] S.-B. Yi, C.H.J. Davis, H.-G. Brokmeier, R.E. Bolmaro, K.U. Kainer & J. Homeyer (2006) Acta Mat. 54, 549-562.

[2] H.-G. Brokmeier, M. Jiang, E. Maawad, B. Schwebke & T. Lippmann (2011) Mat. Sci. Forum 690,198.

[3] Z. Zhong, H.-G. Brokmeier, E. Maawad & N. Schell, (2015) Mat. Sci. Engineering A639, 519.

Failure behaviors of E-form and AZ31 Mg alloys: Crack initiation and propagation during mini-V-bending tests Jaiveer Singh1, Min-Seong Kim1, ByungKyu Kim2, Dong-Ik Kim2, Shi-Hoon Choi1 1Department of Printed Electronics Engineering, Sunchon National University, Suncheon, Jeonnam, 540-950, Republic of Korea. 2High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seongbuk-gu, Seoul, 136-791, Republic of Korea

Deformation and failure behaviors of E-form fine grain (EFG), E-form

coarse grain (ECG) and AZ31 magnesium (Mg) alloys sheets were

investigated using a mini-V-bending test. These rolled sheets of Mg

alloys with different initial textures and grain sizes were studied to

reveal the role of strain heterogeneities through thickness direction

and crack initiation on the bended surface at different punch

strokes. The evolution of the microstructure and microtexture of the

deformed E-form and AZ31 Mg alloys were analyzed via an electron

back-scattered diffraction (EBSD) technique. Finite element analysis

(FEA) was used to capture the heterogeneous distribution of

longitudinal-strain components through the thickness direction

under mini-V-bending at different punch strokes. The relationships

between punch stroke, bending radius and longitudinal-strain at the

tension and compression zones were established. EBSD analysis

revealed that compression and double twins along with shear

localization by dislocation slip were the main deformation

mechanisms in the tension zone while tensile twins were a main

deformation mechanism in the compression zone in E-form and

AZ31 Mg alloys during mini-V-bending. The effects that deformation

twinning had on the crack initiation and propagation sites in E-form

and AZ31 Mg alloys were also investigated. The networks of

compression {1011} and double {1011} − {1012} twins in the

tension zone were closely related to the crack initiation and

propagation during mini-V-bending at room temperature. A resolved

shear stress (RSS) criterion which is based on the Schmid tensor, was

also used to analyze the activation of twin variants in rolled E-form

and AZ31 Mg alloys. The E-form Mg alloys with a weaker texture

show better formability or deformation behaviors during mini-V-

bending compared to AZ31 alloy with a stronger texture.

ABSTRACTS MONDAY AM - DEFORMATION 19

Towards high ductility in magnesium alloys - the role of grain boundary misorientation and deformation compatibility Jie Suna, b, Li Jina, Jie Donga, Fenghua Wanga, Shuai Donga, Wenjiang Dinga,c, Alan A. Luob, d aNational Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai 200240, PR China. bDepartment of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210, USA cState Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, PR China. dDepartment of Integrated Systems Engineering, The Ohio State University, Columbus, OH 43210, USA

This paper investigates the role of grain boundary misorientation

and grain-level deformation compatibility in the plasticity of

magnesium alloys, using in-situ tension in scanning electron

microscopy (SEM) combined with electron backscattered diffraction

(EBSD) and digital image correlation (DIC) techniques. The majority

of activated dislocation slip traces were found to form in pairs across

grain boundary, and basal-to-basal (B-B) slip pair was the dominate

type. Grain boundaries with misorientation about 10-30° around

[0001] axis were found to promote the activation of B-B slip pairs. In

addition, a geometric parameter, m’, can be used to quantify the

possibility for the activation of B-B slip pairs. More activation of

basal B-B slip pairs was found around the boundaries with higher m’

values. Furthermore, a material with misorientation distribution

related to a higher average m’ value would achieve more elongation.

Therefore, optimizing misorientation distribution could be a new

solution to improving the ductility of Mg alloys in the future.

Texture and microstructure evolution of magnesium sheets during bending J. H. Cho1, Y. S. Lee1 and G. Lee1 1Korea Institute of Materials Science, Changwon, South Korea

AZ31 magnesium sheets fabricated by twin-roll casting were bent

using controlled bending machine at various temperatures. Initial

texture and microstructure of AZ31 sheets reveals a strong basal

texture and equiaxed grains. During bending, inner surface (concave

side) experienced compressive stress and negative strains occurred.

While, outer surface (convex side) went through tensile stress and

positive strains occurred. Different deformation mode on each side

caused by bending resulted in dynamic texture evolution. Twinning

in addition to slip played an important role. Annealing also affected

grain structure and mechanical properties changed.

Variant selection of {10-12}-{10-12} double twins during the tensile deformation of Mg alloys R.L. Xin1, C.F. Guo1, J.J. Jonas2, G. Chen1, Q. Liu1 1College of Materials Science and Engineering, Chongqing University, Chongqin, China. 2Department of Materials Engineering, McGill University, Montreal, Canada.

Secondary {10-12} twins can form within primary {10-12} twins in

Mg alloys, forming {10-12}-{10-12} type (extension-extension) twins.

Such secondary {10-12} twinning is sometimes associated with very

small or even negative values of the Schmid factor (SF). The

formation of such negative SF twins must therefore be attributed to

local effects. The variant selection of {10-12}-{10-12} secondary

twins is analyzed by employing a geometric compatibility factor

linking the twinning and slip accommodation modes. To generate

such unusual twins, specially designed samples were machined out

of a thick, hot-rolled coarse-grained AZ31 alloy plate. These samples

were subsequently deformed in tension along the normal direction

of the plate. Under such conditions, all six primary {10-12} variants

were activated, and selected secondary variants were produced at

the intersections of the primary variants. The crystallographic

aspects of the secondary variants are analyzed and linked to the

crystallographic features of the intersecting primary twins. Although

ten different orientation relationships have the potential to form,

only two were observed. Here most of the secondary twins had

misorientations of 49.7°<-909-4> with respect to their hosts. The

observed variant selection is explained in terms of strain

accommodation by basal glide in the host primary twins.

ABSTRACTS MONDAY AM – RUDY WENK 20

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

In-Situ Studies of Microstructures under Deep Earth Conditions: from Texture Analysis to Multigrain Crystallography S. Merkel Université de Lille, 59000 Lille, France

In 2000, Rudy Wenk published the first paper describing a full in-situ

texture analysis from diamond anvil cell measurements in which he

analyzed the compression texture in hcp-Fe at 211 GPa [1]. The

experimental method was later significantly improved and applied

to other higher pressure devices such as the deformation-DIA [2].

Over the years, the combination of lattice strain and texture analysis

have allowed for a new understanding of microstructures in

minerals and metals under the conditions of deep planetary interiors

[3,4]. This field of research is now being extended to more advanced

methods allowing the tracking of microstructures at the individual

grain level [5]. This presentation will review the advances in the

analysis of textures and microstructures under deep planetary

conditions that, thanks to the contribution of Rudy Wenk and the

people who gravitated around him, became a strong and dynamic

field in texture analysis. I will start with an overview of the methods,

developments, and results that were allowed thanks to the

contribution of Rudy Wenk and will finish my presentation with

results of more recent experiments in which we follow

transformation microstructures grain by grain and in-situ in deep

planetary materials.

[1] H.R. Wenk, S. Matthies, R.J. Hemley, H.K. Mao, J. Shu (2000) Nature 405 1044

[2] H.R. Wenk, G. Ischia, N. Nishiyama, Y. Wang, T. Uchida (2005) Phys Earth Planet Inter 152, 191

[3] S. Merkel, A. Kubo, L. Miyagi, S. Speziale, T. S. Duffy, H.K. Mao, H.R. Wenk (2006) Science 311, 644

[4] L. Miyagi, W. Kanitpanyacharoen, P. Kaercher, K. K. M. Lee, H.R. Wenk (2010) Science 329, 1639

[5] A.D. Rosa, N. Hilairet, S. Ghosh, J.-P. Perrillat, G. Garbarino, S. Merkel (2016) J Geophys Res 121, 7161

Deformation and texture development in lower mantle mineral phases: What does seismic anisotropy in the deep Earth tell us about deformation? Lowell Miyagi Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112-0111, USA

In many regions of the Earth’s deep interior, seismologists observe

anisotropic propagation of seismic waves. This is believed to be due

to deformation induced texturing of rocks in the Earth’s interior as a

result of solid-state mantle convection. If deformation behavior and

its relationship to texture and anisotropy development are well

understood, observations of seismic anisotropy can be used to infer

dynamic processes occurring in the deep Earth. However, deformation studies on lower mantle mineral phases

present unique challenges. Recreating relevant pressures and

temperatures in the laboratory is challenging, and the mineral

phases of interest are unquenchable or highly unstable at ambient

conditions, necessitating in-situ analysis.

One of Rudy Wenk’s major contributions is in the field of high

pressure and high temperature texture studies. By combining

unconventional deformation devices such as the diamond anvil cell

with radial synchrotron x-ray diffraction, Rudy developed a

technique to allow in-situ measurement of lattice strains and texture

development as samples undergo deformation at high pressures and

temperatures. Texture measurements combined with polycrystal

plasticity modeling can be used to infer deformation mechanisms

active during an experiment. Once deformation mechanisms are

established, results can be extrapolated to more complex

deformation scenarios such as slab subduction and mantle

convection. This presentation will discuss work on lower mantle

mineral phases that I began as a Ph.D. student with Rudy in 2004

and that continues to the present.

Deformation texture evolution of ω-Zr at high pressure Arul Kumar Mariyappan1, N. Hilairet2, Y. Wang3, R.J. McCabe1, I. J. Beyerlein4, C. N. Tomé1 1Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA. 2CNRS-UMET, Université Lille 1, 59655 Villeneuve d'Ascq, France. 3Center for Advanced Radiation Sources, Argonne National Laboratory, Argonne, IL, 60439, USA. 4Mechanical Engineering and Materials Departments, University of California Santa Barbara, Santa Barbara, CA, 93106, USA

Transition metal zirconium has stable hexagonal close packed (α)

structure at ambient conditions and it transforms to simple

hexagonal (ω) structure under high pressure and/or high rate

deformations. Unlike the ground state α-Zr, the plastic slip modes of

ω-Zr or composite α-Zr containing retained ω-phase are not yet

known. In this work, for the very first time, we have studied the

plastic deformation behavior of ω-Zr through quasi-static

deformation texture evolution. Controlled high-pressure

experiments to transform α-Zr to complete ω-Zr followed by quasi-

static compression test of ω-Zr are performed. Initial and

deformation texture at different strain levels of ω-Zr is measured

using in-situ X-ray diffraction. Visco-Plastic Self-Consistent (VPSC)

crystal plasticity modeling tool is employed to predict the

deformation behavior and texture evolution of ω-Zr. Comparing the

predicted deformation texture with the measurements, we develop

an understanding of crystallographic slip activity in ω-Zr. In this

work, we also studied the influence of initial α-microstructure on the

transformation texture and also on the deformation texture

evolution of ω-Zr.

ABSTRACTS MONDAY AM – RUDY WENK 21

Preferred orientation in a linear viscous flow: High T torsion experiments on Diopside-Anorthite aggregates J. Gómez Barreiro1, H.-R. Wenk2, E. Ribacky3, G. Dresen3, Y. Ren4, J.M. Benítez Pérez1

1University of Salamanca, Salamanca, Spain. 2University of California, Berkeley, USA. 3GeoForschungsZentrum, Postdam, Germany. 4Argonne National Laboratory, Argonne, USA.

Understanding deep Earth rheology mainly relies on indirect

observations. The knowledge we have about the behaviour of rocks

and minerals at different conditions and its correlation with physical

properties (e.g. elasticity), determines how we interpret and model

geophysical data in geodynamic terms (e.g. seismic signal). However,

fundamental questions like the correlation of deformation

mechanisms and mechanical response of polyphasic aggregates at

the Earth interior conditions are not well understood. Experimental

evidences up to date establish the presence or absence of

crystallographic preferred orientation (CPO) or texture as

unequivocal proof of dislocation / diffusional creep dominance, as

well as the mechanical behaviour. Here we show texture in torsion-

deformed polymineral aggregate, composed of anorthite and

diopside (50%). Texture symmetry is coherent with the simple

shearing and the mechanical behaviour is linear-viscous

(Newtonian). Visco-plastic self-consistent numerical simulation of

texture and microstructural observation suggest that a cooperation

of dislocation activity and grain-boundary sliding/diffusion better

explain the results. All these features are opposed to the common

belief that restricts to non-Newtonian rheologies the development

of CPO. This is significant since seismic anisotropy in Earth has been

correlated with the presence of texture. Our results demonstrate

that no rheological behaviour can be derived only from seismic

anisotropy, geophysical observation or texture presence in

polyphasic aggregates.

ABSTRACTS MONDAY AM - RECRYSTALLIXATION 22

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

Texture and microstructure of advanced high strength steel after fast heating and short annealing R.H. Petrov1,2 F.M. Castro Cerda1,3, Ilchat Sabirov4, Athina Puype1, Dorien De Knijf5 and L.A.I. Kestens1,2 1Ghent University, Ghent, Belgium, 2Delft University of Technology, Delft, The Netherlands, 3Universidad de Santiago de Chile, Santiago, Chile, 4IMDEA-Materials Institute-, Madrid, Spain, 5OCAS-nv, Belgium

The microstructure and texture changes in advanced high strength

steels after conventional (10°C/s), and ultrafast (400-1000°C/s)

heating and very short soaking times of ± 0.5s were studied. The

steels with initial microstructure of ferrite and perlite or ferrite and

tempered martensite were 50 or 75% cold rolled before the

annealing. All heat treatments were carried out on a Gleeble

thermo-mechanical simulator and the maximum annealing

temperature was in the two-phase austenite-ferrite temperature

range. The annealing was followed by quenching at an average

quench rate of ~-160 °C/s. This type of treatment is also known as

“flash” annealing. Microstructures and textures of the samples were

studied by optical microscopy, scanning electron microscopy and

electron backscatter diffraction.

The results of the texture analyses of the individual structural

constituents show that heating rates as high as 400°C/s, 800°C/s and

1000°C/s and very short soaking times (0.2-0.5s) can shift the start

of the recrystallization of ferrite to high temperatures. Additionally,

it causes the formation of the intercritical austenite either from

recrystallized or non-recrystallized (or recovered) ferrite. As a

consequence, the microstructure refines and characterizes with very

fine partially recrystallized or recovered ferrite grains and finely

distributed martensitic islands, bainite, Widmanstätten ferrite,

retained austenite and undissolved cementite. The martensite

texture formed after fast heating, short annealing and quenching is

very similar to the initial texture after cold rolling (texture memory

effect) but with lower intensity. After increasing the soaking time

from 0.5 s to 30 s or 60 s, the recrystallization and grain growth take

place and the effect of fast heating vanishes.

The results of this work could be of importance for development of

industrial heat treatment processing routes with application of fast

and ultra-fast heating combined with very short soaking.

Texture evolution during partial recrystallization annealing in high strength automotive steels S. Janakiram1, Jai Prakash Gautam1 and L.A.I. Kestens2

1School of Engineering Sciences and Technology, University of Hyderabad, Gachibowli, Hyderabad, Telangana 500046, India. 2Department of materials science and engineering, Ghent University, Ghent, Belgium

Currently automotive industry is aiming to reduce the weight of the

car body while maintaining its strength and formability. The

crystallographic texture is one of the main physical parameters

responsible for controlling the formability of steel. The texture of

steel is a function of materials and process parameters: chemical

composition, hot band microstructure and texture, cold rolled

reduction, recrystallization process. With the increasing use of high

strength steels is essential to study more comprehensively the

concurrent ferrite recrystallization and second phase effect during

annealing of two phase steels or, more generally, high strength

steels. It reveals some clear differences in recrystallization behaviour

with the well-studied single phase ferrite steels: presence of new

nucleation sites in fragmented regions, grain growth limited by

pearlite band. In general, the behaviour of second phases as

pearlite, bainite during recrystallization annealing is not well

established.

The present study is mainly focused on effect of hot deformation

temperature (Tnr) on the recrystallization texture after 80% cold

rolling. Special attention is paid to understand the nucleation and

growth mechanism with the effect of second phase as pearlite and

bainite constituent. Results are analysed with the help of optical

microscope, Vickers hardness and texture through EBSD.

Results clearly show the effect of hot deformation (Tnr) on

microstructure and recrystallization kinetics. Microstructure

consisted of coarse non banded and fine banded morphology of

ferrite, pearlite and bainite. Faster Recrystallization kinetics are

observed for Below Tnr compared to above Tnr. Heterogeneous

nucleation of grains took place with orientation nucleation

mechanism. Results suggest the reappearance of hot band texture at

the onset of recrystallization.

The effect of the pre-heating temperature and heating rate on the textures of cold-rolled low-carbon steel F.M. Castro Cerda1,2, L.A.I. Kestens1,3 and R.H. Petrov1,3 1Ghent University, Ghent, Belgium, 2Universidad de Santiago de Chile, Santiago, Chile, 3Delft University of Technology, Delft, The Netherlands .

The effect of heating rate on the microstructure and texture of ultra-

low and low carbon steel has been recently studied. The heat

treatments carried out in these studies are of the “peak-annealing

and quenching” type, in which the test specimens are heated

continuously, held for very short times (less than 0.5 s) at the peak

temperature and quenched. However, the industrial application of

the peak-annealing (also called flash) process on cold-rolled steel

plate might require a slight modification. In the present study, the

effect of a pre-heating stage on the textures of 50% and 75% cold-

rolled low carbon steel is investigated. The pre-heating stage

consists of heating the test specimens at a conventional rate (10

°C/s) to a pre-heating temperature and holding isothermally for 30 s,

followed by the 'peak annealing' type of thermal cycle. Two pre-

heating temperatures were selected, namely 300 and 400°C. After

the pre-heating stage, the peak-annealing experiments were carried

out under two heating rates (10 and 400 °C/s) with a holding time of

1.5 s, followed by quenching (~-160 °C/s).

ABSTRACTS MONDAY AM - RECRYSTALLIZATION 23

The pre-heating temperatures show negligible effects on the cold-

rolled microstructure and ferrite textures. The recrystallization

textures are rather insensitive to the pre-heating stage. The increase

of the heating rate after the pre-heating stage shows strengthening

in the intensity of grains oriented close to <111>//ND, as well as in

some <110>//RD texture components. The texture memory effect

plays a role in the formation of the martensite texture after

quenching, whereby the texture is also affected by the heating rate

on the nucleation of austenite. The results indicate that a pre-

heating stage before the application of peak-annealing cycles does

not modify the microstructure and the textures in a significant way.

The results of the present study are expected to be of significance

for the industrial application of ultrafast heating rates to cold-rolled

low carbon steel plate.

Effects of initial microstructure/texture and cold-rolling reduction on texture and r-value in ferritic stainless steel sheets. Kou NISHIMURA1, Jun-ichi HAMADA2, Yoshiharu INOUE1, and Kenichi MURAKAMI1 1Nippon Steel and Sumitomo Metal Corporation, Kitakyushu City, Japan. 2Nippon Steel and Sumikin Stainless Steel Corporation, Hikari City, Japan

The Lankford value (r-value), which is a basic index for the

formability of ferritic stainless steel sheets, is closely related to their

recrystallization textures. In this study, the effects of initial

microstructure/texture and cold-rolling reduction on the r-value and

recrystallization behavior of ferritic stainless steel were investigated

to clarify {111} nucleation behavior.

Three Type 409L ferritic stainless steels were used. They had

different initial microstructure and area fraction of {111} grains.

After cold-rolling and annealing them, we investigated the

relationship between formability and recrystallization texture by the

r-value test and X-ray measurement. Furthermore, the Vickers

hardness test and EBSD measurement were conducted to clarify

recrystallization behavior.

It became clear that the effects of cold-rolling reduction on

recrystallization texture depended on initial microstructure and

texture because the main nucleation site changes from the vicinity

of grain boundaries to deformed {111} grains according to cold-

rolling reduction.

Texture characterization of AISI 316 L steel processed by selective laser melting F.C. Pinto1, M. Avalos2, R.E. Bolmaro2 and H.R.Z. Sandim1 1Lorena School of Engineering, University of Sao Paulo, Lorena, Brazil. 2Instituto de Física de Rosario, Rosario, Argentina.

Additive manufacturing is an emerging technology able to produce

unique microstructures and textures in traditional materials,

depending on the chosen scanning strategy. We report the main

results of the texture characterization of AISI 316L austenitic

stainless steel processed by selective laser melting (SLM) of metal

powders. To date, the literature presents very little information on

the texture evolution of this steel, or even other alloys processed by

SLM, upon post-processing heat treatments. The material was

characterized in the "as-processed" condition and after isothermal

annealing within a wide range of temperatures (950-1150oC), with

emphasis on the evolution of the crystallographic texture during

coarsening of the microstructure. The texture of the as-processed

steel is rather weak, composed mainly of {011} planes contained on

the deposition plane and perpendicular to the growth direction,

with tetragonal symmetry promoted by the alternative deposition of

[011]<001> layers, where the <001> points alternatively along the

successive laser scan directions. Further isothermal annealing

changes both texture and mesotexture, in particular the increase of

-3 special twin boundaries.

ABSTRACTS MONDAY AM - ENGINEERING 24

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Materials

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Microstructure effects of mechanical alloying on SPS sintered Fe-Al-Si powders J. Kopeček1, J. Remiášová1, L. Klimša1, F. Průša2, K. Nová2 and P. Novák2 1Institute of Physics of the AS CR, Prague, Czech Republic. 2University of Chemistry and Technology Prague, Prague, Czech Republic.

Iron aluminides/silicides are cheap materials with interesting

corrosion and mechanical properties, mainly at high temperature

range. Nevertheless, their preparation is not easy task and powder

methods are frequently used to prepare volume material. We

exploit previous knowledge of our team both in reactive sintering

and Fe-Al-Si system to investigate the microstructure, phase

composition, mechanical and corrosion properties of cast and

mechanical alloyed sintered materials [1-4].

The phases’ formation mechanism in Fe-Al-Si system during

mechanical alloying is described in the Fe-Al-Si alloy powder

prepared by mechanical alloying. The powders of the Fe-Al-Si alloy

prepared under the optimized conditions are consolidated by spark

plasma sintering (SPS) in the next step. The mechanism and kinetics

of the formation of intermetallics will be described by the analysis of

the morphology, microstructure and phase composition after

various process durations and milling conditions. It is very important

to characterize the processes during MA at the level of individual

powder particles, therefore special techniques including FIB-SEM,

EBSD, TEM and nanoindentation will be utilized. We evaluate the

influence of the production technology on the microstructure and

related mechanical and corrosion properties.

Here the results obtained on the Fe – 20 wt. % Al – 20 wt. % Si will

be presented with respect to mechanical alloying and spark plasma

sintering process optimization based on SEM and EBSD

investigations.

[1 P. Novák et al. (2011) Intermetallics 19 1306. [2] P. Novák et al. (2011) Powder Metallurgy 54 167. [3] P. Novák et al. (2010) J. Alloys Comp. 493 81. [4] P. Novák et al. (2010) J. Alloys Comp. 497 90.

Oxidation Kinetics of Steel: The Defining Role of Substrate Micro-texture H. K. Mehtani*, M. I. Khan, A. Durgaprasad, S. Parida, M.J.N.V. Prasad and I. Samajdar Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai (400076), India

Two different steel grades, IF (interstitial free) and fully pearlitic

(near eutectoid), were used. Substrates with different micro-

textures showed remarkable difference in oxidation kinetics. In fully

ferritic IF steel highest oxidation rate was in ND//<111> grains; while

in eutectoid steel the rate of oxidation scaled with ferrite-cementite

interface area and the exact nature of the phase boundary. In both

grades, the oxidation rate did relate to the chemical nature and the

physical morphology of the oxide film. Hetero-epitaxial growth

stresses of the oxide film were measured by using Raman

Spectroscopy and multiple {hkl} grazing incident X-ray diffraction.

Such stresses were shown to have a clear relationship with the

substrate micro-texture, and determined the oxidation kinetics of

the respective grades/microstructure.

Effect of temperature and crystallographic orientation on superelastic strain of FeNiCoAlTaB single crystals R. Chulist1, T. Tokarski2, G. Cios2, W. Maziarz1, N. Schell3 Y.I. Chumlyakov4 1Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta Street, Kraków, 30-059, Poland. 2AGH University of Science and Technology, Academic Centre for Materials and nanotechnology, Mickiewicza 30, 30-059 Krakow, Poland. 3Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Strasse 1, D-21502 Geesthacht, Germany. 4 Tomsk State University, Siberian Physical Technical Institute, Tomsk 634050, Russia

Fe-based alloys (Fe-28Ni-17Co-11.5Al-0.5Ta-0.5B abbreviated

NCATB) belong to a new family of shape memory alloys showing a

large superelastic strain at room temperature [1,2]. However,

significant strain differences between single and polycrystals are

observed. Therefore, to provide an insight into the mechanism of

superelasticity observed in NCATB alloys single crystals with <100>,

<110>, <111> and <112> orientations were compressed at different

temperatures (273, 123, and 77 K). Elastic, plastic or elasto-plastic

response are observed depending on the orientation and

deformation temperature. The global and local orientation

measurements are determined by diffraction of high-energy

synchrotron radiation and electron backscatter diffraction,

respectively. The results are discussed with respect to

crystallographic orientation, deformation mode, precipitations and

phase transformations.

[1] Y. Tanaka, Y. Himuro, R. Kainuma, Y. Sutou, T. Omori, and K. Ishida, Science 327, (2010) 1488

[2] T. Omori, K. Ando, M. Okano, X. Xu, Y. Tanaka I. Ohnuma, R. Kainuma, and K. Ishida, Science, 333 (2011) 68

Crystal Plasticity Finite Element Modeling of Polycrystal NiTi Shape Memory Alloy (SMA) S. Dhala, S. Mishra, A. Alankar

Department of Mechanical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, 400076, India

NiTi SMA are a special class of metallic alloys that remember their

original undeformed shape. These metals are capable of recovering

large strains (order 6-7%) by heating (shape memory effect) or at

higher ambient temperatures, simply by unloading

(pseudoelasticity). In this paper, we present a crystal plasticity finite

element model for polycrystal pseudoelastic NiTi SMA considering

ABSTRACTS MONDAY AM - ENGINEERING 25

slip, phase transformation and deformation twining modes. The

model is used to predict macroscopic mechanical response under

uniaxial deformation. Finite element analyses are carried out for a

representative volume element consisting of randomly oriented

grains and subjected to periodic boundary conditions. Material

parameters for slip, transformation and twin modes are determined

by fitting the stress-strain curves with single crystal experimental

results. Predicted deformation behavior of polycrystalline NiTi SMA

is compared against the experimental data. Localized stress

concentrations and martensite transformation are observed due to

heterogeneous deformation driven by crystallographic orientations.

There is a good agreement between simulation results and

experimental data, which validates the proposed crystal plasticity

model. The model can be further extended to investigate the effect

of temperature, strain and texture on mechanical behavior of

pseudoelastic NiTi SMA.

Deformation Analysis of Alumina Compressed at High Pressure Using Electron Channeling Contrast Imaging (ECCI) and Electron Backscatter Diffraction (EBSD) S. Kaboli, and P.C. Burnley University of Nevada Las Vegas, Las Vegas, USA.

Polycrystalline α-alumina is commonly used as material for

deformation pistons in sample assemblies for the D-DIA apparatus

used in in-situ X-ray synchrotron deformation experiments. Despite

the higher strength of alumina relative to geological materials under

study, the alumina pistons occasionally fail during D-DIA

experiments, meaning that the pistons bulge out or shorten during

compression. The piston failure results in underestimated stress

measurements for the sample. These underestimated stress values

result in internally inconsistent and irreproducible datasets from D-

DIA experiments which have been commonly reported by previous

workers. Thus, deformation analysis of alumina compressed at high

pressure in the D-DIA apparatus is all the more urgent. The

objectives of this study are two-fold. First, we use electron

channeling contrast imaging (ECCI) in field emission scanning

electron microscope (FE-SEM) to image dislocations under known

diffraction conditions and identify activated slip systems in grains

that are not twinned. Second, we use electron backscatter

diffraction (EBSD) to identify twin laws operating in alumina. In

comparison to conventional deformation analysis using transmission

electron microscopy (TEM) on thin foils, the main advantages of SEM

include fast and non-destructive bulk specimen preparation and

statistically reliable results from a large field of view in a bulk

sample.

We establish a successful procedure for specimen preparation and

microscope operation to perform dislocation imaging with ECCI in

FE-SEM. We perform EBSD analysis to identify the angle–axis pair of

misorientation between two adjacent crystals domains to identify

the twin laws. This analysis involves a comparison between

experimental and theoretical pole figures for rhombohedral

twinning and assessment of the symmetry and rotational

relationship between twin and parent grains in order to confirm the

type of twinning. Additionally, we use EBSD to provide a quick

automated quantitative analysis of twinning laws distributed across

the polycrystalline aggregate.

Our preliminary ECCI images in FE-SEM confirmed the presence of

edge-on basal dislocations obtained for the first time from deformed

alumina at high pressure. We demonstrate the invisibility criterion

through variations in channeling contrast with sample tilt series

similar to dislocation analysis commonly performed in TEM. For

twin law identification, we analyzed our EBSD data by comparing six

experimental pole figures for the basal {0001}, prismatic {10-10}, {1-

210}, pyramidal {10-11}, and rhombohedral {01-12} families of

planes and the <02-21> family of directions with corresponding

theoretical pole figures for rhombohedral twinning. We also verified

rhombohedral twin symmetry and the 85° rotational relationship

between twin and parent grains. We also noted the presence of

surface porosity which implies that the orientation of the twins with

respect to the overall compression direction is not informative since

the collapse of the porosity would create large variations in the local

stress field across the sample.

ABSTRACTS MONDAY AM -CHARACTERIZATION 26

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National Laboratory

Dictionary Indexing Approach for Electron Diffraction Modalities F. Ram, S. Singh and M. De Graef Carnegie Mellon University, Pittsburgh, USA.

All single crystal diffraction modalities, whether they use electrons

(EBSD, PED, ECP, CBED, …) or X-rays (transmission and reflection

Laue) have in common the need for an algorithm to extract the

lattice orientation from the positions of the features (spots, bands,

lines, …) in the diffraction pattern. We will refer to the orientation

extraction process as “indexing the pattern.” Finding features in a

diffraction pattern requires an image processing step (the Hough

transform in the case of EBSD) followed by identification of the

locations of the main features and conversion of those locations into

an orientation. In the dictionary indexing approach, one relies on a

forward model to predict diffraction patterns for a range of

orientations uniformly sampling orientation space, SO(3), and then

each of those pre-computed patterns is compared, using an image

similarity metric, to each of the experimental patterns; the

orientation corresponding to the best matching pattern is then

assigned as the solution.

In this contribution, we will briefly describe a physics-based forward

model for the generation of EBSD patterns, as well as a new

mathematical approach to obtaining a uniform sample of

orientations. The forward model consists of (1) a Monte Carlo

simulation to determine the depth-energy-direction histogram of

back-scattered electrons for a given sample tilt and incident electron

energy; (2) a dynamical electron scattering simulation covering the

range of possible electron directions; and (3) a geometrical model

for the sample-detector geometry. We will provide examples of

forward calculations for a number of different crystal structures.

This process is then repeated for each crystal orientation taken from

a uniform set of orientations based on the cubochoric sampling of

SO(3). The resulting pattern dictionary can then be used to find the

best matching pattern for each experimental pattern; the dot

product between normalized pattern vectors provides a useful and

efficient similarity metric.

While this indexing process is slow compared to the Hough-based

indexing available in commercial EBSD packages, we will show that

this approach has a number of advantages: (1) robustness against

noise (the approach does not look for pattern features but compares

entire patterns); (2) ability to refine the orientation sampling to

improve the pattern match; (3) ability to index overlapping EBSD

patterns, which occur near grain boundaries; (4) ability to obtain

average orientations, since the approach stores not only the best

matching pattern orientation, but several near matches as well; (5) a

precise definition of the confidence index for the pattern match.

Finally, since there is always a best match, there are no un-indexed

points that require manual or semi-automated correction after the

indexing process has concluded. Needless to say, the approach

requires that every EBSD pattern be stored on disk, which results in

very large data sets when fine scale sampling is used or when full-

scale patterns are employed.

We will provide examples of dictionary indexing for a number of

material systems, including Nickel; a geological sample consisting of

garnet, clinopyroxene and amorphous melt; shot-peened Aluminum;

and a high-cycle fatigued ultra-fine grained steel.

Improved spatial and angular resolution of EBSD-based texture measurement of deformed and fine-grained materials F. Ram1, S. Singh1, A. Gholinia2, T.L. Burnett2, B. Winiarski2 and M. DeGraef1 1Carnegie Mellon University, Pittsburgh, USA . 2University of Manchester, Manchester, UK.

The Electron Backscatter Diffraction technique (EBSD) in a Scanning

Electron Microscope is a standard choice for measuring the micro-

texture of a bulk material. The EBSD analysis based on the Hough

transform works very efficiently in most cases; and when lattice

rotation gradients are small or a high accuracy is required, the cross-

correlation-based analysis is the substitute. When a highly deformed

or an ultra-fine grained material is being characterized, however, the

performance of these two methods worsens. This is due to pattern

degradation as a result of the largest dimension of the beam-

specimen interaction volume exceeding the spatial variation length

of the lattice rotations.

To capture this spatial variation, the electron beam-specimen

interaction volume must be reduced in volume, which requires

reducing the electron beam energy. At 5 keV, the largest dimension

of the beam-specimen interaction volume in Al is about 80 nm; it is

260 nm at 20 keV. Adopting this strategy partially alleviates the

spatial resolution issue, but does not improve the performance of

the two above-mentioned methods because at a lower accelerating

voltage, the EBSD pattern quality is severely degraded. The number

of points whose orientations can be determined by the Hough-

transform analysis decreases from 95% at 20kV to 5% at 5 kV in a

shot-peened Al sample.

In this contribution, we will review the dictionary-based indexing

approach and show how it robustly deals with low-quality patterns.

The same shot-peened aluminum specimen measured at 5 keV was

analyzed by dictionary indexing, which successfully determined the

orientation of more than 85% of the measured points. At 10 keV,

even the smallest grains near the shot-peened surface could be

resolved and indexed successfully. Our analysis will show that we

have improved the effective spatial resolution of EBSD, so that

details of the deformed microstructure (multi-walled grain and sub-

grain boundaries) are revealed that could not be imaged and

quantified by EBSD before.

ABSTRACTS MONDAY AM -CHARACTERIZATION 27

Pole figure measurement methods for centerless X-ray diffractometers M. Benke1, M. Sepsi1 and V. Mertinger1 1University of Miskolc, Miskolc, Hungary.

The present paper introduces new texture measurement methods

developed for mobile/fixed centerless X-ray diffractometers. Using

these methods pole figures can be obtained with all the benefits of

centerless diffractometers: no need for sample cutting, flexibility in

case of large components with complex shapes, short measuring

time and portability. The paper describes the measurement

methods, includes the validations with conventional pole figure

measurements and provides instances of applications of the new

technique.

Quantification of local anisotropy and microstructure-property relationships using canonical correlation analysis Sudipto Mandal, Jacky Lao and Anthony D. Rollett Carnegie Mellon University, Pittsburgh, PA, USA.

Microstructure-property relationships in two-phase titanium alloys

have generally been evaluated qualitatively and are based on their

macroscopic behavior. However, structural and texture changes at

the microscopic scale can result in failure of a material much before

the macroscopic predictions. With the advent of powerful

computers and advanced data-driven techniques, the relationship

between local anisotropy, microstructural features and mechanical

properties can be efficiently quantified for a statistically large

volume of the material.

Canonical correlation analysis (CCA) has been used to understand

the effect of microtexture and microstructural features on the

deformation behavior and texture evolution during uniaxial

compression for Ti-6Al-4V. CCA is a multivariate approach that can

reveal the global sensitivities of individual variables in a model or a

phenomenon. CCA is preferred over other commonly used

sensitivity techniques because it provides a measure of both the

relative contribution of the variable and its interrelationships with

other variables. The microstructural and texture features analyzed in

this study include particle size, particle shape, grain orientation,

intragranular misorientation and grain boundary characteristics. An

elastoviscoplastic fast Fourier transform (FFT) simulation is used to

predict the local stress and strain rate behavior based on

representative 3D microstructures.

The predictions from CCA are compared with expected material

behavior based on physical explanations and experimental

observations. Quantifying local microstructure-property

relationships will aid in the identification of local sites more prone to

failure and the factors most likely to cause them. A better

understanding of these relationships will eventually allow greater

control over the performance of the material under extreme

conditions.

Geometric distortion corrections of EBSD Scans Francois Brisset1, Torkjell Breivik2, Bjørn Eske Sørensen2, Yingda Yu3, Jean-Claude Menard4 and Jarle Hjelen2,3

1ICMMO, CNRS / Unversité Paris-Saclay, Université Paris-Sud, Orsay, France. 2Department of Geoscience and Petroleum, NTNU, 7491 Trondheim, Norway. 3Department of Material Science and Engineering, NTNU, 7491 Trondheim, Norway. 4Ahead Microscopy, 1 allée des jonquilles, 78390 Bois d'Arcy, France

Some types of materials require EBSD mapping from large areas to

get representative results because grain sizes are in the order of

several mms and statistically significant crystal preferred

orientations require several hundred or thousands of individual

grain measurements. Typical examples are large silicon wafers,

geological thin sections, welding, etc. EBSD maps are acquired in x-

and y-directions with a certain overlap and in the end stitched

together to get a large area EBSD map. The larger the individual

square maps the faster the total acquisition will be as there will be

less stage moves and less recombination of areas. However, and

especially at low magnification, the scanned area will be distorted

due to the high EBSD tilt angle, typically 70˚ and this scanned area

will have a trapezoidal distortion if no shape correction is applied.

The distortion will increase with decreasing magnification. As a

consequence, stitching such areas with trapezoidal distortion leads

to mismatch between neighbor areas. To correct for this distortion a

theoretical or an experimental calibration method could be applied.

In the present case a calibration method has been developed to

correct for the distortion. A calibration specimen with square grids

has been used for the calibration procedure. The calibration

specimen was tilted and the SEM parameters (magnification, tilt

angle, high voltage, working distance) were set to the same

experimental values as for the real EBSD scan (done after the

calibration procedure). The EBSD detector should be in the in-

position during calibration. The calibration procedure is carried out

by marking 4 points on the distorted square grid. These 4 points

must be the corners on a square grid and the points should be close

to the 4 corners of the tilt corrected and dynamically corrected

electron image. The stage moves are applied either moving only x

and y in the case of a eucentric stage with a stage 70° tilted or

moving x, y and z if a pre-tilted specimen holder is used. In addition

of this procedure, automatically acquired, indexed and

reconstructed multi-area maps will be presented.

ABSTRACTS MONDAY PM - PLENARIES 28

MONDAY PM PLENARY SESSION

Deformation and grain growth of hexagonal metals: new insights with conventional and high resolution EBSD techniques V. Tong and T.B. Britton Department of Materials, Imperial College London, London, UK

Hexagonal metals are critical for many high-value high-risk applications. For instance, Zircaloy-4 is used in nuclear reactors in the form of thin-

walled fuel rod cladding tubes. In this application, maintaining a fine grain size is important to withstand the large thermal, mechanical and

irradiation stresses in operation. Under certain conditions, abnormally large grains, or blocky alpha (often >500μm in size) grow within the small

grained matrix (~15μm), which is undesirable for structural integrity of the fuel rod cladding.

Understanding the mechanism by which blocky alpha nucleates and grows is essential for both optimising manufacturing processes and

understanding in-service performance. In this work, EBSD and HR-EBSD analysis have been used to understand the nucleation of blocky alpha

grains in annealed three point bend specimens.

The final equilibrium size of the blocky grains is shown to be dependent only on the magnitude of the strain before annealing. However, the texture

of the annealed samples changes with both the tensile/compressive sense and magnitude of the strain. The texture differences in these four

regions (high and low strain regions on either side of the neutral axis) have been measured using EBSD. This likely due to a change in deformation

mode within the tensile and compressive faces of the bend specimen. Comparisons of heat treated samples and as-bent samples have been used

to understand the influence of deformation microstructure on abnormal grain growth.

A mechanism for blocky alpha formation can be proposed based on these results. It is likely that strain concentrations provide the driving force for

nucleation of blocky alpha structures. Nucleant grains are likely to be at local strain concentrations such as twin tips during deformation, so that

the nuclei have a different texture to the bulk plate. These nucleant grains consume other grains as they grow, producing a texture in the final

blocky alpha structure different to the parent texture.

Effects of texture on mesoscale characterization and modeling of heterogeneous deformation T.R. Bieler1, A. Chakraborty1, C. Zhang1, S. Balanchandran1 H. Phukan1, L. Wang2, Z. Zheng2, P. Kenesei3, J.-S. Park3, P. Eisenlohr1, M.A. Crimp1, C.J. Boehlert1 1Michigan State University, East Lansing, MI, USA, 2Shanghai Jiao Tong University, Shanghai, China, 3Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA.

Constitutive models for crystal plasticity simulations require an understanding of how the relative slip resistance varies among several slip systems,

and how these resistances evolve with strain. Because the details of deformation are complex in hexagonal systems, there is considerable

variability in experimental measurements of the critical resolved shear stress (CRSS) for different slip systems; ratios of prism/basal vary from 0.2-

0.8 in pure Ti. The variation is almost this large from assessments made on the same material with different methods. The CRSS value for <c+a> slip

cannot be measured directly, as basal or prism <a> slip is typically activated even if <c+a> slip has the maximum possible resolved shear stress.

Because many experiments show that <c+a> slip is active, knowing <c+a> CRSS values are important. Consequently, indirect methods such as

surface slip trace observations have been used to obtain relative slip resistances using a statistical approach recently developed by our group [1].

The statistics of these measurements depends on the texture and the deformation direction of the sample. To assess the ability to extract CRSS

values, a computational study that examines if the CRSS values used to computationally deform a polycrystal with different textures can be

extracted by assuming that slip systems showing large values of accumulated shear can be assessed to extract the CRSS input values.

Our group has also estimated CRSS using nanoindentation experiments in tandem with crystal plasticity models by matching surface topography

and load-displacement history using optimization strategies. Indentation experiments cause a state of stress that depends on the location under

the indent, which also evolves with depth of displacement. While indentation on a single grain makes the effect of texture irrelevant, at least two

measurements on significantly different grain orientations are required to sufficiently assess the operation of a sufficiently large variety of slip

systems.

Another approach uses in-situ far-field high-energy x-ray diffraction experiments to identify grains in which the lattice rotation is caused primarily

by a single slip system, from which the CRSS at yield of that particular slip system is extracted using from the measured strain (stress) tensor [2].

These experiments reveal a bimodal distribution correlated with surface vs. interior grains that indicates that hydrostatic stress states affect the

CRSS, so non-Schmid effects are probably significant.

As there are many variables involved in these techniques, the confidence in extracted CRSS values is an open question, leading uncertainty in

plasticity models developed subsequently. Thus, a systematic comparison of all three experimental methods has been carried out using two

ABSTRACTS MONDAY PM - PLENARIES 29

different lots of commercially-pure titanium, one with a weak texture and one with a strong texture. Supported partially by several past and

current NSF/DMR grants and by DOE/BES DE-FG02-10ER46637.

[1] H. Li et al., (2013), Acta Mater. 61, 7555-7567. [2] L. Wang et al. (2017), Acta Mater., in revision.

ABSTRACTS MONDAY PM - DEFORMATION 30

Symposium D: Deformation Textures Session: Titanium

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Understanding the texture and anomalous recrystallization behaviour of warmed rolled CP-Ti João Quinta da Fonseca The University of Manchester, Oxford Road, Manchester M12 9PL, UK

The texture of warm rolled commercial purity titanium (CP-Ti)

becomes stronger as the rolling temperature increases. Even more

unexpectedly, the recrystallization rate of the warm rolled material

increases with rolling temperature. The aim of work reported here

was to investigate the origin of these surprising observations and, in

particular, to determine to what extent this was a consequence of

the deactivation of twinning at higher temperatures.

CP-Ti was rolled at RT, 150C, 300C and 450C to different reductions

up to a maximum of 50%. The bulk texture of the rolled material was

measured using EBSD, which was also used to obtain higher

resolution maps for studying twinning. Crystal plasticity finite

element modelling (CPFEM) was used to simulate the texture

evolution during rolling. The material model used was calibrated on

a set of compression tests performed at the same temperatures and

at strain rates comparable to those of rolling. The relative changes

with temperature of the critical resolved shear stresses (CRSS) for

slip and twinning were inferred from the values available in the

literature and validated via comparison with the Lankford

coefficients measured after compression testing.

The CPFEM calibration revealed that as temperature increases, the

amount of twinning decreases as expected. Furthermore, although

all the CRSSs decrease with temperature, the CRSS ratio of

pyramidal <c+a> to prismatic slip increases with rolling temperature.

Both these effects are necessary to predict the increase in texture

strength observed. In addition, they offer an explanation for the

apparent anomalous increase in recrystallization rate. As the plastic

anisotropy increases, the deformation of the material becomes

more heterogeneous, as does the spatial distribution of stored

energy. Therefore, although more recovery occurs at the higher

rolling temperatures, the amount of plastic strain in the grains well

aligned for easy slip increases. This creates regions of high stored

energy and high local misorientation, which act as preferential sites

for recrystallization, causing an apparent higher rate of

recrystallization during annealing.

Microstructure and texture Evolution during Thermo-Mechanical Processing of Ti-6Al-4V Titanium Alloy Jyoti Jha1, Bhagyaraj J1, Suraj Toppo2, Rajkumar Singh2, Asim Tewari1, Sushil Mishra1 1Indian Institute of Technology Bombay, Mumbai, India. 2KCTI, Bharat Forge Limited, Pune

Forging of alpha-beta Ti-6Al-4V alloy having lamellar microstructure

at slower strain rates and just below transition temperature

produces the globular microstructure, which can be further heat

treated to obtain the bimodal (equiaxed and lamellar)

microstructure. The degree of deformation also governs the extent

of formation of globular microstructure. To understand the

influence of deformation on the microstructure evolution, a range of

compression tests have been carried out at 20%, 50% and 80%

deformation, at strain rate of 0.1s-1 and temperature 950℃. The

shearing of alpha lamellae under the compressive loading is

apparent for 20% deformation. The shearing of lamellae is more

intense for 50% deformation that produces the globular

microstructure. The decreasing trend of the flow stress with the

strain, can be interpreted by globularisation, dynamic

recrystallization and texture evolution. There is marked increases in

the flow stress after 60% deformation has been observed. To

characterize the increase in the flow stress after 60% deformation

further test has been carried out for 80% deformation. The

metallographic examination for 80% deformed specimen shows the

reappearance of lamellar structure, though in smaller grain size. The

TEM micrograph reveals the twinning as the other deformation

mechanism for the highly deformed Ti-6Al-4V with initial lamellar

microstructure.

Microstructural and texture characterization and 3D modeling of Ti-6Al-4V alloys with different processing histories Sudipto Mandal1, Jacky Lao1, Vahid Tari1, D.S. Shih2 and Anthony D. Rollett1 1Carnegie Mellon University, Pittsburgh, PA, USA. 2Boeing Research and Technology, St. Louis, MO, USA.

This work explores the processing-microstructure-property

relationships in two-phase titanium alloys such as Ti-6Al-4V that are

used for aerospace applications. The motivation is reduction of the

buy-to-fly ratio of titanium alloys. Microstructures produced by the

conventional Vacuum Arc Remelting (VAR) method are compared

with the relatively new Electron Cold Beam Hearth (EBCH) melting.

Microstructure and texture of the two sources of materials are

characterized using Scanning Electron Microscopy (SEM), X-Ray

Diffraction (XRD) and Electron Backscatter Diffraction (EBSD). To

model their properties, three-dimensional synthetic digital

microstructures are generated based on the experimental

characterization data. An open source software package,

DREAM.3D, is used to create heterogeneous two-phase

microstructures that are representative of titanium alloys. Crystal

plasticity models based on the fast Fourier transform algorithm (FFT)

are used to simulate the deformation response of the material at

both microscopic level and continuum level. A data driven approach

is followed to understand and model the processing-microstructure-

property relationships in Ti-6Al-4V alloy.

ABSTRACTS MONDAY PM - DEFORMATION 31

Study of residual stresses in Ti-7Al using theory and experiments K. Chatterjeea, A. J. Beaudoina, J.Y.P. Kob, H. Philippd, J. Beckerb,d, P. Purohitd, S. M. Grunerb,c,d,e

aMechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 West Green Street, Urbana-Champaign, IL 61801, USA. bCornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853, USA. cDepartment of Physics, Cornell University, 109 Clark Hall, Ithaca, NY 14853, USA. dLaboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA eKavli Institute for Nanoscale Science, Cornell University, Ithaca, NY 14853, USA

Finite element simulations are carried out to follow the evolution of

residual stresses in Ti-7Al (hcp) alloy, as developed through a

process of combined bending and tension. A virtual polycrystal

geometry is generated using the position and orientation

information of the grains. This information is obtained from High

Energy Diffraction Microscopy (HEDM) experiments performed at

the Advanced Photon Source of Argonne National Laboratory. A

finite-element model using mesoscopic field dislocation mechanics

[1] is employed to simulate the deformation history of bending,

tension and unloading. The difference between the applied and the

experimental bending stresses are used to initialize a field of

geometrically necessary dislocations in the simulation. Strain rate

sensitivities of prismatic and basal slip systems of Ti-7Al are

evaluated from high energy x-ray diffraction data collected during

stress relaxation situation and are used as input to the simulation. A

separate set of HEDM experiments are performed for determination

of the strain rate sensitivities of different slip systems of Ti-7Al.

These experiments are conducted at the Cornell High Energy

Synchrotron Source (CHESS) and diffraction spots are collected using

a prototype mixed mode pixel array detector with CdTe sensor [2,3]

– a fast detector capable of capturing images at a maximum rate of 1

kHz. Conclusions from this combined experimental and simulation

work are that grains deform mainly via prismatic slip, and accurate

characterization of grain orientations and rate-sensitivity are needed

to model the development of grain-level residual stresses.

[1] A. Roy, S. Puri & A. Acharya (2006) Modelling and Simulation in Materials Science and Engineering. 15, S167.

[2] M.W, Tate, D. Chamberlain, K.S. Green, H.T. Philipp, P. Purohit, C. Strohman & S. M. Gruner (2013) Journal of Physics: Conference Series. 425, 062004.

[3] J. Becker, M.W. Tate, K.S. Shanks, H.T. Philipp, J.T. Weiss, P. Purohit, D. Chamberlain, J.P.C. Ruff, S.M. Gruner (2016) Journal of Instrumentation. 11, P12013.

ABSTRACTS MONDAY PM – RUDY WENK 32

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

Texture analysis from synchrotron and Neutron diffraction: Rietveld method applied to biological materials, commercial-pure Titanium and Shales from sedimentary basins I. Lonardelli1, L. Lutterotti2, M. Bortolotti2 and HR. Wenk3 1Comar SpA via G. Galilei 266, Zimella (VR), Italy. 2Dipartimento di Ingegneria Industriale, Università di Trento, Italy. 3Department of Earth and Planetary Science, University of California, Berkeley, CA 94720, USA

The analysis and the precise characterization of anisotropy in

geophysics as well as in materials science is crucial in order to have a

complete understanding of all the aspects related to plastic

deformation occurred in a wide range of materials.

From several years, synchrotron and neutron diffraction techniques

helped us to investigate at the micro and nano-scale level the

preferred orientation of sub-domains in a significant volume of

matter analyzed. The Rietveld method was implemented and

applied by Prof. Wenk and his research group in order to obtain

quantitative and reliable information regarding not only texture but

also the structure and microstructure that are averaged over the

experimentally sampled volume.

Here we present three different fields in which the method was

applied to determine quantitatively the crystallographic texture:

mineralized biological samples with hydroxyapatite fabric [1],

commercial pure Titanium during high temperature phase

transformation/recrystallization process [2] and very oriented multi

phases Shales with complex crystal structures [3].

[1] I. Lonardelli, HR. Wenk, L. Lutterotti J. Synchrotron, Rad. 12, (2005), 354-360.

[2] I. Lonardelli, N. Gay, HR. Wenk, M. Humbert, S.C. Vogel and L. Lutterotti Acta Mater. 55 (2007) 5718-5727.

[3] I. Lonardelli, HR. Wenk, Y. Ren Geophysics (2007), Vol.72, n° 2, p. D33-D40.

Olivine-antigorite phase transformation: microstructures, phase boundary misorientation and seismic properties L. F. G. Morales1, D. Mainprice2 and H. Kern3 1ETH Zurich, ScopeM, Zurich, Switzerland. 2 Geosciences Montpellier, Montpellier, France.

Antigorite-bearing rocks are thought to contribute significantly to

the seismic properties in the mantle wedge of subduction zones.

Here we present a detailed study of the microstructures and seismic

properties in a sample of antigorite-olivine schist. We have

measured crystallographic orientations and calculated the seismic

properties in three orthogonal thin sections. Microstructures

indicate that deformation is localized in the bands with high

antigorite fractions, resulting in strong crystallographic preferred

orientations (CPOs) with point maxima of poles to (100) parallel to

lineation and poles to (001) to the foliation normal. Olivine CPO

suggests deformation under high temperature and low stress, with a

[100] fibre texture. The CPO strength varies with grain size, but is

strong even in fine-grained antigorite, and larger grains tend to

display higher internal misorientation. Phase transformation

relationships between olivine and antigorite are evident in phase

boundary misorientation analysis, (100)ol||(001)atg being more

frequent than [001]ol||[010]atg. Two new phase transformation

relationships between olivine and antigorite, with a relationship to

deformation has been documented. Seismic velocities decrease

while anisotropy increases with increasing antigorite modal content.

Antigorite grain shape has a weak effect on seismic velocities, but

affects the anisotropy. While CPO-derived seismic velocities agree

well with ultrasonic measurements for sections parallel to the

foliation determined for the same sample, they are between 0.2-1.0

km/s faster than ultrasonic velocities measured normal to the

foliation. The slower ultrasonic velocities possibly result from

attenuation on grain boundaries and voids that may remain open

even at pressures of 600 MPa.

The seismic properties of quartzites during the alpha-beta transition and the influence of texture David Mainprice1, and H. Kern2 1Géosciences Montpellier UMR CNRS 5243, Bâtiment 22, CC 060, Université de Montpellier,Place Eugène Bataillon, 34095 MONTPELLIER cedex 05, France. 2Institut fur Geowissenschaften, Universität Kiel, Kiel, Germany

The preferred crystal orientation (texture) of quartz is characteristic

for many quartz-bearing rocks such as quartzite and granite.

Quartzite has been the subject of texture analysis for nearly 100

years. One of fascinating aspects of quartz is the alpha-beta phase

transition that has a very strong impact on elastic properties and

therefore also on anisotropic seismic properties quartz-bearing

rocks in the Earth’s continental crust. Seismologists have claimed in

recent years that they detect a velocity drop in the crust that they

interpret as the alpha-beta transition. Their analysis is entirely

elastically isotropic, but we know that quartzites typically have

strong texture and hence will have anisotropic elastic properties.

In this presentation we will present a digital model of the anisotropic

elastic properties of quartz alpha-beta transition. Firstly, the model

will be tested against experimental ultrasonic measurements at

temperature and pressure on quartzites. Secondly, we will quantify

the anisotropic seismic properties for several quartzites with

different textures at various pressure and temperature conditions

corresponding to the depth range in the Earth’s crust of 15 to 17 km

where seismologists have claimed to observe the alpha-beta

transition in-situ.

ABSTRACTS MONDAY PM - RECRYSTALLIZATION 33

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

Effects of Nucleation at Shear bands on Texture Evolution in Cold-Rolled IF Steels H. Miura1, M. Kobayashi1, T. Tsuji1, H. Minami2 and Y. Funakawa2 1Department of Mechanical Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, Aichi, 441-8580, Japan. 2Sheet Products Research Dept., Steel Research Laboratory, JFE Steel Corporation, 1 Kawasaki-cho, Chuo-ku, Chiba 260-0835, Japan

Cold-rolled IF steels with added 25 and 41ppm C, which initial grain

sizes before cold-rolling were 57 and 34 m respectively, were

annealed to investigate static recrystallization (SRX) nucleation

behavior and the effects on texture evolution. Observations from

transverse direction (TD) revealed development of obvious amount

of shear bands to subdivide pancake grains that induced

misorientation distribution in the cold-rolled samples. SRX

nucleation occurred preferentially at grain boundaries and shear

bands. Softening due to onset of SRX looked to be more affected by

initial grain size and deformation microstructure rather than the

amount of C content. That is, onset of SRX was earlier in the excess C

added IF steel with initial grain size of 34 m than that in the

conventional one with 57 m, while the apparent activation energy

was around 300 kJ/mol in both samples. SRXed grains formed at

shear bands possessed rather large misorientations to the mother

grains, which implies occurrence of discontinuous SRX. These results

indicate the important role of shear banding as well as initial grain

size on SRX behavior. In the process to full recrystallization,

however, they were eroded by (111) grains to form strong (111)

texture.

Texture development during static recrystallization of a warm and hot rolled ferritic stainless steels A. Després1, C.W. Sinclair1, J-D. Mithieux2, F. Chassagne2

1Department of Materials Engineering, University of British Columbia, Vancouver, Canada V6T 1Z4. 2 Aperam Research Center, BP 15, 62230 Isbergues, France

The effect of static recrystallization on the texture development of

hot rolled ferritic stainless steels is presented, with a focus on the

mechanisms of nucleation and growth leading to the deleterious α

fibre texture. Industrial transfer bars were rolled to thickness

reductions of 50% and 75%, at 700°C (warm rolling) and 1100°C (hot

rolling), then annealed at 950°C. As the rolling temperature

increases, the recrystallization texture following annealing exhibits a

transition from a γ fibre texture to a “spread” α fibre texture

(comprising orientations between {001}<110>, {112}<110> and

{100}<001>). In warm rolled products, a “classic” in-grain nucleation

of γ fibre grains at shear bands is observed. In hot rolled products,

regardless of the reduction, nucleation occurs by bulging of α fibre

subgrains at pre-existing grain boundaries. This preferred

development of α fibre grains is associated with the absence of

shear bands (even at high reductions), thus leaving pre-existing grain

boundaries as the only possible nucleation sites.

Quantification of recrystallization simulation datasets by chord length distribution and principal component analysis M.I. Latypov1, M. Kühbach2, I.J. Beyerlein1, and S.R. Kalidindi3 1University of California Santa Barbara, Santa Barbara, USA. 2Max-

Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany. 3Georgia Institute of Technology, Atlanta, USA.

Understanding such complex phenomena as recrystallization

requires integrated investigation approaches combining

experiments and simulations. The development of advanced

characterization and modeling methods provides for access to ever

increasing amount of hierarchical microstructural information. For

example, modern highly parallelized approaches allow for simulating

rare but statistically significant nucleation events under rigorously

controlled conditions by monitoring millions of nucleation

candidates. Such rich datasets demand efficient microstructure

quantification protocols that will help detecting salient

microstructural features and facilitate establishing quantitative

relationships between the microstructure of the material, its

properties, and processing conditions.

In this talk, we present a microstructure quantification framework

based on higher-order statistical descriptions and dimensionality

reduction techniques suitable for both experimental and simulation

datasets. It will be shown, as a specific example, that directionally

resolved chord length distribution in combination with principal

component analysis allows for quantification of recrystallization

datasets capturing microstructural features beyond widely used

first-order descriptions (e.g., mean grain size). The potential of the

framework to serve as a basis for quantitative processing–structure–

property relationships and efficient visualization of microstructure

databases is also discussed.

ABSTRACTS MONDAY PM - ENGINEERING 34

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Materials

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Microstructure and Texture evolution during thermo-mechanical processing of low-symmetry metals R.J. McCabe1, M. Zecevic2, C.A. Miller1, D.R. Coughlin1, B. Clausen1, S.C. Vogel1, M. Knezevic2, D.W. Brown1, D.J. Alexander1 1Los Alamos National Laboratory, Los Alamos, NM, USA. 2Univerity of New Hampshire, Durham, NH, USA.

Thermo-mechanical processing of low-symmetry metals typically

results in anisotropic microstructures and properties that can vary

across a component and adversely affect performance. For

instance, residual stresses that develop in formed and heat treated

components with varying texture and anisotropic thermal expansion

behavior can cause components to warp during machining

operations. Here we use neutron diffraction and electron

backscatter diffraction to study the variation in local texture as a

function of processing path. We first examine the effects of

different clock-rolling schedules, where plates are rolled at 0, 90,

225, and 315 orientations to a total reduction of 25%, but with

different combinations of reduction per step. The plates are then

formed into hemispherical components and texture measurements

are made as a function of position. As expected, the texture varies

from pole to equator, but there are also considerable texture

differences longitudinally about the component due to the initially

anisotropic clock rolling textures. In addition, there are significant

texture differences measured from the inside radius to the outside

radius of the component. These results are compared to modeling

efforts that incorporate the VPSC polycrystal plasticity model with

finite element simulations.

Reactive Texturing of Y-TZP and Ce-TZP in a 17 Tesla Magnetic Field O. Van der Biest1, D. Vriami1, E. Beaugnon2 1Department of Materials Engineering, K.U.Leuven, Belgium. 2Laboratoire National des Champs Magnétiques Intenses (LNCMI), Grenoble, France.

Tetragonal zirconia powder cannot be aligned by applying a strong

magnetic field during green forming of a powder compact. In prior

work we have shown that a strong texture can be achieved in 3Y-TZP

by using a reactive texturing technique. One uses a suspension that

contains monoclinic zirconia that can be oriented in a strong field

during green forming for instance by slip casting. The monoclinic

(100) plane is oriented perpendicular to the magnetic field direction.

When a mixture of pure monoclinic zirconia powder and 8 mol%

yttria co-precipitated zirconia is used, a strong texture of single

phase 3Y-TZP is obtained after reactive sintering for 3 hrs at 1650°C.

The (001) plane of the tetragonal phase is perpendicular to the

magnetic field direction, i.e., the c-axis is aligning parallel to the

field. In the strong magnetic field of 17.4 T used in the present work,

the texture of the cast green ceramic, can be measured (Lotgering

factor f = 0.15) whereas at lower fields texture in the green body is

barely discernible. After sintering a Lotgering factor of 0.8 is

measured. More detailed analysis of the texture showed a texture

index of 32.5.

We attempted to texture Ce-TZP by a similar strategy but with less

success. The suspension consisted of a mixture of monoclinic

zirconia and nanometric ceria powder. Orienting the monoclinic

zirconia particles during slip casting was again clearly achieved with

a Lotgering factor of 0.3 calculated from the monoclinic reflections

again with the (100) plane normal to the magnetic field. After

reactive sintering a single phase tetragonal microstructure is formed

if the sintering temperature is chosen high enough. However, the

resulting Lotgering factor for the 001 reflections was only 0.3 and a

texture index of about 3 was measured.

It appears that for successful reactive texturing of zirconia the

differences in composition between the monoclinic phase and the

phase containing the stabilizing element should be as small as

possible.

Texturation of polycrystalline NiMnGa alloys via mechanical training studied by in-situ neutron diffraction and SEM EBSD Y. D. Zhang1, 2, Z. B. Li3, N. F. Zou1,3, W. M. Gan4, M. Hofmann5, X. Zhao3, C. Esling1, 2 and L. Zuo3 1Laboratoire d'Étude des Microstructures et de Mécanique des Matériaux (LEM3), CNRS UMR 7239, Université de Lorraine, Metz, France. 2Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures (DAMAS), Université de Lorraine, Metz, France. 3Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, China. 4German Engineering Materials Science Centre (GEMS), Helmholtz-Zentrum Geesthacht (HZG) Outstation at FRM II, Garching, Germany. 5Forschungsneutronenquelle Heinz Maier-Leibnitz(FRMII),TUMünchen, Garching, Germany.

Studies have revealed that the martensite of intermetallic NiMnX

(X=Ga, In, Sn), especially NiMnGa alloys, with crystal structure

modulation exhibit strong reversible deformation capacity under an

applied force. This capacity is originated from the abundant twinning

or shuffling systems of each martensite variant. For NiMnGa with

7M modulated martensite, the activation of various deformation

systems and their influences on microstructure have not been

sufficiently studied. The present work presents a thorough

investigation on these issues. A NiMnGa alloy with 7M modulated

martensite at room temperature was compressed and the

deformation process was investigated by in-situ neutron diffraction

and SEM EBSD, respectively. It is revealed that the 7M martensite

possesses various new twinning and shuffling systems in addition to

the conventional twinning systems, and all can be activated to

achieve variant reorientation. The activation of the conventional

twinning systems results in volume fraction change of the existing

variants, whereas the activation of the new twinning or shuffling

systems gives rise to the formation of new 7M variants or NM

ABSTRACTS MONDAY PM - ENGINEERING 35

martensite. Via the reorientation of the variants, the alloy is finally

textured with the <010> direction of all martensite variants parallel

to the compression direction. The results of the present study

provide comprehensive information on the deformation

mechanisms of NiMnGa 7M martensite.

Role of Texture on Enhanced Magnetocaloric Effect in Heusler Alloys Following Stress Assisted Thermal Cycling Michael V. Mcleod1, Bhaskar S. Majumdar2, Zafer Turgut1, and Sven Vogel3 1AFRL, Wright Patterson AFB, Ohio 45433, 2New Mexico Tech, Socorro, NM 87801, 3Los Alamos National Laboratory, NM 87545

Heusler alloys of the type X2YZ type often exhibit unique structural

and magnetic response, which manifest in magnetic shape memory

behavior as well as large magnetocaloric effect (MCE), the latter

being important for non-polluting solid state refrigeration. In these

alloys, X and Y belong to 3d transition metals with one of them

dominating the magnetic moment, and Z is an element in the IIIA-VA

group. They generally possess wide solid solubility, such that non-

stoichiometry as well as elemental substitution can alter the

martensite stability as well as magnetic exchange interactions

between atomic sites, causing a strong coupling between two first

order transformation temperatures, namely structural (TM) and

magnetic transformations (TC). Under such situations, a magnetic

field can bring about a structural transformation, known as

magnetostructural transformation, which manifests in large or

‘giant’ MCE.

The focus of this work was on two variants of Ni2MnGa alloys,

where the Ni:Mn ratio in non-stoichiometric composition or Cu

substitution at the Mn site at stoichiometric composition were

utilized to bring the magnetostructural transformation close to room

temperature (RT). Specific alloys that we refer to had compositions:

(a) Ni2Mn0.76Cu0.24Ga, and (b) Ni54Mn21Ga. In the former case,

substitution of Cu has been shown to increase martensite start

temperature (Ms) from 200 K to 321 K, while the Curie temperature

TC was simultaneously decreased from 376 K to close to Ms. The

transformation temperatures for alloy (b) were similar. Alloy (a)

exhibited a martensitic structure at RT that was dominated by body

centered tetragonal (bct, I4/mmm) phase along with minor (10%)

7M (C2/m:b3) modulated monoclinic structure, while the Heusler

austenite phase was described by the ordered fcc (Fm3 m) structure.

Correspondingly, alloy (b) exhibited a fully bct structure in the

martensite state at RT. The MCE values for the two alloys were

approximately -10 J/kg-K for an imposed magnetic field change of 2

Tesla. It is important to note that the easy magnetization axis for

these anisotropic alloys is along the (110) pole of the bct martensite

structure, and that the as processed heat treated material often

have high starting texture along the columnar direction although not

along the easy magnetization axis.

In an effort to enhance MCE, thermal cycling was conducted

between the fully austenite state and martensitic states under a

constant low compressive stress. The rationale was to maintain

integrity of the samples while at the same time imparting (110) pole

texture along the columnar direction, which was also the direction

of the applied magnetic field. Contextually it has been shown in NiTi

alloys that such stress assisted thermal cycling (SATC) using low

superimposed stress are highly efficient in predictable enhanced

texture. In the cycled sample, large increases in MCE of -25 J/kg-K

and -18 J/kg-K were observed for samples (a) and (b), respectively;

i.e., increases 150% and 80%. These significant increases are

correlated with the preferential texture measured using the HIPPO

neuron diffraction apparatus at LANSCE. It is believed that favorable

twin variants reduce pinning of magnetic domains resulting in

enhanced MCE following SATC. The structural and texture changes

are discussed in detail.

ABSTRACTS MONDAY PM - CHARACTERIZATION 36

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National LaboratoryIn-house texture measurement using compact neutron source

M. Takamura1, Y. Ikeda 1, H. Suzuki2, M. Kumagai3, Y Oba4, T. Hama4 and Y. Otake1 1RIKEN, Wako-shi, Japan. 2JAEA, Tokai-mura, Japan. 3tokyo City University, Tokyo, Japan. 4kyoto University, Kyoto, Japan.

A compact accelerator-based neutron source has never been applied

to a texture measurement with neutron diffraction because of its

low neutron flux. However, authors have lately succeeded in

measurement of the diffraction pattern from a ferritic steel using

Riken Accelerator-driven Compact Neutron Source (RANS) [1], and

then applied it to the measurement of texture evolution due to

plastic deformation for steel sheets. In this study, pole figures of IF

(interstitial free) steel sheets with the thickness of 1 mm, including

an as-received sample and plastically deformed samples, were

successfully obtained through neutron diffraction experiments by

suitable experimental arrangements in RANS. The total

measurement time for sixty diffraction patterns to acquire one pole

figure was only 300 minutes. The pole figures obtained by RANS

exhibit typical tendencies in the texture evolution of an IF steel,

which shows the capability of the in-house compact neutron source

for the analysis of plastic deformation mechanism in conjunction

with texture. The possibility to expand the application of the in-

house compact neutron source to the investigations in crystal

plasticity model will also be discussed.

[1] Y. Ikeda, et al. (2016) Nuclear Inst. and Methods in Physics Research, A, 833, 61.

Texture analysis with monochromatic neutrons at STRESS-SPEC W.M. Gan1, M. Hofmann2, H.-G. Brokmeier1,3 1Gemern Engineering Materials Science Center at MLZ, Garching, Germany. 2FRM II, TU München, Garching, Germany. 3Intitute of Materials Science and Engineering, Clausthal University of Technology, Clausthal-Zellerfeld, Germany

The engineering materials science diffractometer STRESS-SPEC at

FRM II (Garching, Germany) is designed to be applied equally to

texture and residual stress analyses by virtue of its very flexible

configuration [1]. Due to its high penetration of neutrons and

comparably high neutron flux STRESS-SPEC allows a combined

analysis of global texture, local texture, strain pole figure and FHWM

pole figure in a wide variety of materials including metals, alloys,

composites, ceramics and geological materials.

In order to obtain good statistics and use the limited beam time

efficiently, a continuous scan routine has been developed for pole

figure measurement which saves about 30% positioning time

compared to step size scan. A method using dual wavelength

produced by PG monochromator has been optimised for pole figure

measurement of single phased metals. Moreover, a robot is used as

a sample changer and Eulerian cradle substitute which greatly

enhances the capabilities for standard pole figure measurement and

as well as local texture analysis on irregular shape samples [2, 3]. As

a future development it is planned to implement a second area

detector which will double the 2-theta coverage angles (together up

to 30°) to further speed up data acquisition time. In this contribution

we will present all these methods for pole figure measurements

with specified related examples.

[1] M. Hofmann, W.M. Gan, J. Rebelo-Kornmeier & M. Schoebel (2013) Neutron News. 24, 14.

[2] H.-G. Brokmeier, W.M. Gan, C. Randau,. M.Voeller, J. Rebelo-Kornmeier & M. Hofmann (2011) Nucl. Instr. Meth. A642, 87.

[3] C. Randau, H.-G. Brokmeier, W.M. Gan, M.Voeller, M. Hofmann. W. Tekouo, N.AL-hamdany, G. Seidl & A. Schreyer (2015) Nucl. Instr. Meth. A794, 67.

Development and verification of simultaneous measurement system for texture and phase fraction by time-of-flight neutron diffraction at iMATERIA Y. Onuki1, A. Hoshikawa1, S. Sato1, S. Nishino1, T. Ishigaki1 and T. Tomida2 1Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Japan. 2Ibaraki Prefectural Government, Tokai, Japan.

Neutron diffraction is a powerful tool for investigations of metallic

materials because neutron interacts not only with the surface layer

but also with whole exposed volume. This is especially advantageous

to analyze the statistic properties, e.g., texture, phase fraction and

dislocation density. By using TOF (time-of-flight) type neutron

diffraction, statistically reliable measurement is possible in a simple

sample environment in short time duration. We have previously

developed the texture measurement scheme at iMATERIA, the 20th

beamline at J-PARC MLF [1]. By using Rietveld texture analysis

technique, texture of each phase in a multiphase material can be

determined [2]. It is possible to obtain the phase fraction as well as

the texture in the analysis. In the current study, we verify the

accuracy of the phase fraction analyzed by the Rietveld texture

analysis. The “multiphase” model samples were prepared by

laminating 20 sheets of ferritic (AISI 430) and austenitic (316L)

stainless steels of 0.3 mm thickness. By changing the number and

width of the austenitic steel in the lamination, the true fraction of

austenite was clearly defined. The analyzed austenite fractions well

agree with the prepared fractions even if the austenite fraction is

low. For example, the analyzed values are 0.62 vol % and 2.49 vol %

for the samples with prepared fractions of 0.61 vol % and 2.47 vol %,

respectively. The texture of austenite is also successfully analyzed

although it becomes somewhat qualitative when the fraction is

below 4 vol %. In the presentation, we will also show some results of

the application to the in situ observations of phase transformation

during heat treatment as well as strain-induced transformation.

[1] Y. Onuki, A. Hoshikawa, S. Sato, P. Xu, T. Ishigaki, Y. Saito, H. Todoroki & M. Hayashi (2016) J. Appl. Cryst. 49, 1579.

[2] H. R. Wenk, L. Lutterotti & S. C. Vogel (2010). Powder Diffr. 25, 283.

ABSTRACTS MONDAY PM - CHARACTERIZATION 37

Neutron and X-ray Diffraction Texture Analysis of Novel Al-Si-Mg Alloy M. Kucerakova, L. Kalvoda, S. Vratislav and J. Capek Department of Solid State Engineering, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Trojanova 13, 120 00 Prague 2.

Texture and microstructure is analyzed on an as-casted specimen of

a novel aluminum-based alloy by means of neutron and X-ray

diffraction (XRD) method using pole figures and inverse pole figures

as the primary data. The Panalytical theta/theta X'Pert PRO

diffractometer with Cr X-ray tube and the KSN-2 neutron

diffractometer located at the research reactor LVR-15 in the Nuclear

Research Institute, plc. Rez, Czech Republic are utilized in collection

of the XRD and neutron data, respectively, followed by data

processing performed within the GSAS and X'Pert Texture SW

environment.

Elemental composition of the specimen provided by instrumental

neutron activation analysis (INAA), X-ray fluorescence (XRF) and X-

ray diffraction (XRD) phase analysis methods is dominated by Al

(79.91 wt.%), Si (9.90 wt. %), Mg (4.19 wt. %), Pb (1.1 wt. %), Fe

(0.69 wt. %) and Ca (0.175 wt. %). Aluminum (cubic, Fm3m), silicon

(cubic, Fd3m) and magnesium silicide (Mg2Si, cubic, Fm3m) phases

are identified by XRD phase analysis as the prevailing

crystallographic phases present in the sample.

Crystallographic preferential orientation analysis of these

constituting phases is then performed and discussed in relation to

other microstructure data and juxtaposed with the theoretical

considerations and simulations based on the elemental composition

of the investigated alloy.

ABSTRACTS TUESDAY AM - PLENARIES 38

TUESDAY AM PLENARY SESSION

Texture analysis of geomaterials: a challenge for EBSD David Mainprice1 1Géosciences Montpellier UMR CNRS 5243, Bâtiment 22, CC 060, Université de Montpellier, Place Eugène Bataillon, 34095 MONTPELLIER cedex 05, France.

Since 1993 Electron Back Scattered Diffraction (EBSD) has become the most popular tool for measuring texture, also called crystal-preferred

orientation in Earth Sciences. EBSD has great advantage to associate the crystal orientation data in an exact location in the microstructure. The

association of orientation and microstructure is the time-honoured method used in geology, when using the universal stage and petrological

optical microstructure. Hence it is no surprise the Earth scientists have quickly adopted the EBSD technique. The application of EBSD to

geomaterials is not as straightforward as for material sciences where synthetic polycrystalline aggregates of controlled; grain size, purity, texture,

often-single phase etc. Geomaterials samples require special sample surface preparation, problems occur because both natural and synthetic

samples often have micro-cracks due to their decompression from high pressure in the Earth or laboratory. Geomaterials typically contain several

minerals with different rates of surface polishing, so minerals have different surface heights. Perhaps the most difficult problems are related low

average atomic number than causes low diffracted intensity, typically low symmetry e.g. monoclinic, that makes indexing more complex and finally

most minerals do conduct electricity, which causes the electron beam to be deflected. Because the Earth Sciences community is small when

compared to materials science the EBSD system suppliers tend ignore some of vital needs of our community, which are; a) very sensitive cameras

with high signal to noise ratio for weak diffraction patterns, b) more reliable indexing for low symmetry crystals, and c) large area mapping as grain

size tends larger than Materials Science applications and d) eucentric SEM stages as this allows for really constant working distance, which helps

indexing performance, and finally e) beyond the Laue class indexing.

Despite all the apparent handicaps of geomaterials they are often on the cutting edge of EBSD because they are very challenging. Several new

studies are working on Ice Ih using cold stages in the SEM at -100°C, results are very encouraging for this geomaterial at the centre of climatic

concerns about the plastic flow of polar ice caps. Traditional quantitative texture analysis using EBSD data have become routine. Recent

developments on misorientation at grain boundaries in single phase or polyphase geomaterials are likely to put the emphasis on the role on grain

boundaries in future studies. To remain topical, I will select several recent topics from Geomaterials.

Relationships of microstructure and device performance in thin-film solar cells D. Abou-Ras Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany

The best performing thin-film solar cells, based on Cu(In,Ga)Se2, CdTe, or halide perovskite (e.g., CH3NH3PbI3) absorber layers, can exhibit

conversion efficiencies of more than 22%. Since in general, a thin-film solar cell consists of a thin-film stack deposited on any substrate material,

such as glass, metal, or polymer, all layers in the stack are polycrystalline. In contrast to photovoltaic devices based on multicrystalline silicon, the

device performance of solar cells with Cu(In,Ga)Se2, CdTe, or halide perovskite absorber layers is not reduced with smaller average grain sizes. At

the example of Cu(In,Ga)Se2 solar cells, it will be outlined which microstructural analyses are conducted on Cu(In,Ga)Se2 thin films, how these

analyses are combined on identical positions with electrical and optoelectronic characterization on the (sub)micrometer scale, and finally, how the

microscopic, electrical properties can be linked to the (macroscopic) device performance.

ABSTRACTS TUESDAY AM - DEFORMATION 39

Symposium D: Deformation Textures Session: Steels – Cold Rolling

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Texture, microtexture and mechanical properties of some Mn steels Satyam Suwas and R. Kalsar Department of Materials Engineering, Indian Institute of Science, Bangalore-560012, India

Deformation texture, microstructure and tensile properties have

been studied in Mn containing TWIP steel in a composition range Fe-

(32-12 Mn-0.6C). Alloys were cold rolled to a large reduction in

thickness (εt≈3). The deformed microstructure has been

characterized by X-ray diffraction and electron back-scatter

diffraction. Bulk X-ray texture reveals the development of Bs-type

texture with deformation. Microstructural features indicate the

occurrence of different deformation mechanisms at different

reduction levels. At very early stage of deformation, dislocation slip

is the dominant mechanism, at intermediate stage, deformation

takes place by twinning, and, at large strains the deformation is

governed by shear banding.

Effect of carbon addition on deformation texture of heavily cold rolled polycrystalline Fe-3%Si Haruhiko Atsumi1, Shuichi Nakamura2 1Nippon Steel & Sumitomo Metal Corporation, Technical Research & Development Bureau, Hirohata R & D Lab., Hyogo Prefecture, Japan. 2Nippon Steel & Sumitomo Metal Corporation, Steel Research Laboratories, Chiba Prefecture, Japan

Deformation textures of heavily cold rolled polycrystalline Fe-3%Si

with 0.0007, 0.002, 0.01, 0.02 mass%C were investigated, in order to

clarify the effect of carbon addition on development of α-fiber

components {100}<011>. The deformation textures of 90% cold

rolled specimens were measured by X-Ray diffraction technique.

Each texture was basically characterized by strong α-fiber and week

γ-fiber components. In addition, the peak intensity of α-fiber

components shifted from {211}<011> to {100}<011>, as increased

amount of carbon addition. According to Taylor’s pencil glide model

proposed by Dillamore and Katoh, {211}<011> is the most stable

orientation in α-fiber components against ideal rolling deformation.

However, in the case of rolling deformation considering width strain,

the orientation rotation from {211}<011> to {100}<011> could be

suggested by the above model. Actually, focused on the macroscopic

deformation, the width of cold rolled specimens increased, as

increased amount of carbon addition. Therefore, we performed

electron back-scattered diffraction (EBSD) measurements of the cold

rolled specimens to identify the origin of the width increasing as the

effect of carbon addition. As a result, the orientation rotation from

{211}<011> to {100}<011> was revealed to be frequently observed

on width edge in deformed grains which were deformed to not only

rolling direction but also width direction by EBSD measurements.

The peak-shift from {211}<011> to {100}<011> with increasing

amount of carbon addition occurred due to that the solute carbon

and FeC precipitates suppressed the deformation in the dolling

direction and activated the slip systems which induced α-fiber

oriented grains to deform in the width direction.

Formation of High Angle Boundaries during Cold-rolling of Ti-added Ultra Low Carbon Steel T. Morikawa1, S. Kira1, K. Fukuda1, M. Tanaka1, K. Higashida1, K. Kimura2, K. Murakami2, K. Ushioda2 1Kyushu University, Fukuoka, Japan. 2Nippon Steel & Sumitomo Metal Corporation, Futtsu, Japan.

Development of deformation microstructures due to cold rolling in

ultra-low carbon steel has been investigated by same sites

observation in the longitudinal plane of rolled sheet by SEM and

SEM-EBSD technique with the increase of thickness reduction.

Particular attention has been paid to the process of the grain

subdivision during the cold-rolling and the formation of new high

angle boundaries in initial grains. The microstructures and the

orientation distribution in the longitudinal plane of the specimen

rolled by 50% reduction in thickness were observed, then the sheet

was subjected to additional rolling, where the sheet was fitted into a

frame made by the same steel in order for the observed longitudinal

plane to deform under a plane strain condition. Some initial grains

were divided into parts elongated along the rolling direction with

formation of slip bands after the additional rolling. SEM-EBSD

analysis revealed that the crystallographic orientation of the divided

parts in the grain gradually rotated with the increase of thickness

reduction. The rotation occurred during rolling contributes the

formation of new boundaries in the initial grain. It is also notable

that fine grains were observed around the new boundaries. The

results suggest that the activation of slip in the grain due to cold-

rolling was enhanced by the constraint of neighboring grains as well

as by the stress factor.

.

ABSTRACTS TUESDAY AM – RUDY WENK 40

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

Quartz textures in rocks – progress in methodology, results and interpretations Karsten Kunze, Luiz F.G. Morales

ETH Zurich, ScopeM, Zurich, Switzerland

Quartz is a common rock-forming mineral, and certainly the mineral

studied most in texture analysis of rocks. There is hardly any texture-

analytical method that had not been applied to identify quartz

fabrics in a diversity of rocks. As a consequence, a broad range of

texture types and preferred orientation patterns have been

reported. Many of them are reasonably well explained and used for

phenomenological interpretations to infer deformation conditions of

rocks, others are still missing well justified understanding.

Particularly, the Y-maximum of c-axes distributions has commonly

been interpreted as due to dislocation glide on prism-a slip systems,

but none of the simulation models for polycrystalline plasticity have

convincingly succeeded to reproduce such a texture type.

This contribution will summarize the progress in methodology,

results and interpretations of quartz textures. Special emphasis will

be given to milestone contributions by Rudy Wenk over many

decades. It will be shown, that analytical methodology has advanced

to high levels of sophistication, providing data of increasing

reliability and detail. Understanding and interpretation has changed

from purely phenomenological approaches to material science like

simulations based on the underlying mechanisms. Nevertheless,

fundamental enigmas remain, some of which will be addressed.

The role of Dauphiné twinning on the development of quartz ribbons: implications for quartz superplasticity L.Lagoeiro1, R. Santos1, C. Cavalcante1, P. Barbosa2 1Federal University of Paraná, Curitiba, Brazil. 2University of Brasília, Brasília, Brazil.

Quartz ribbons in high-grade rocks from the Além Paraíba-Pádua

Shear Zone (Southeast Brazil) were analyzed using the EBSD

technique. The shear zone was developed under amphibolite to

granulite facies conditions (~660-900 °C at 700 MPa) [1]

corresponding to a depth of approximately 25 km. The rocks are

striped mylonitic gneisses where recrystallized feldspar aggregates

alternate with quartz ribbons. The analyzed thin sections were cut

parallel to the mineral lineation (elongate quartz crystals) and

perpendicular to the gneissic banding. The ribbons are highly

elongate with aspect ratios that can easily reach 20:1. Quartz

crystals show slight undulose extinction with very large subgrains

and are free of recrystallized grains. Grain boundaries are

predominantly lobate, indicating a high mobility. The c-axes of

quartz ribbons are oriented with a maximum between the Z and the

Y-direction, synthetically inclined to the dextral sense of shear of 35˚

to the Z-direction. The pole figures show features characteristic of

the Dauphiné twinning, such as the single c-axis orientation, six

rather than three pairs of positive {r} and negative {z} rhombohedral

planes. The Dauphiné twinning can be observed across a

misorientation profile in a twinning region of the ribbon with

misorientation angles at around 60˚. This can be confirmed by the

distribution of misorientation angle/axis pair relationships with a

peak at 60˚, associated with a rotation around the c-axis.

The crystallographic texture observed for the mylonitic gneiss

suggests that activation of rhombohedral planes accounts for the

plastic deformation of these rocks. Experimental, theoretical and

numerical studies are consistent with twinning acting to orient some

direction of the crystals of greater compliance parallel to the

compression direction. In this case twinning cannot accommodate

permanent deformation, but can reduce the stiffness of the crystal

to make it more deformable [2]. Our findings indicate that the

presence of Dauphiné twinning had an important influence on the

deformability of quartz during ribbon formation. The rhomb planes

of quartz are orthogonally aligned to the compression direction and,

according to the Menegon et al. [3], this crystallographic

configuration evolves to a parallelism between the directions of the

most compliant and the maximum compression. In such a position

quartz grains may have been highly deformed in a condition close to

a superplastic behavior.

[1] T.M. Bento dos Santos, J.M. Munhá, C.C.G. Tassinari, P.E.

Fonseca & D.N. Coriolano (2010) GEOSCI J. 15(1), 27. [2] J. Tullis (1970) Science 168, 1342. [3] L. Menegon, S. Piazolo & G. Pennacchioni (2011) Contrib.

Mineral. Petrol. 161(4), 635.

Microstructure and microtexture characterization of avian eggshells M. Avalos1,2, V. Tartalini2, P. Risso2, A. V. Lopez3, M. E. Hauber4, J.C. Reboreda3, R.E. Bolmaro1 1Instituto de Física Rosario, CONICET-UNR, Rosario, Argentina. 2Centro Científico Tecnológico, Lab. Microscopía Electrónica de Barrido, Rosario, Argentina. 3Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires. 4Department of Psychology, Hunter College and the Graduate Center of the City University of New York, New York, USA.

The avian eggshell is the final product of a calcium carbonate

biomineralization process. As a result, it mainly consists of calcite

crystals of different sizes and orientations. Texture and

microstructure are structural traits that influence the mechanical

properties of the eggshell. These structural characteristics are of

particular interest for evolutionary interactions in avian brood

parasitism behavior because thicker parasitic eggshells are more

resistant to punctures by hosts or conspecifics.

In this work eggshell samples of three species of avian brood

parasites (Icteridae: Molothrus) and seven hosts (Icteridae,

Tyrannidae, Cardinalidae, Mimidae, Troglodytidae) were analyzed to

characterize the microtexture and microstructure of the eggshell in

ABSTRACTS TUESDAY AM – RUDY WENK 41

order to document variation between species. Low vacuum Electron

Backscatter Diffraction (EBSD) scans were performed in the

eggshells of the selected avian species in the Radial-Tangential

planes. We complemented these scans with X ray pole figures from

the same species’ samples.

The results show that together with crystal size/thickness

relationship, the networks of grain boundaries seem to be a

microstructural characteristic to take into account for understanding

the resistance to puncturing. The analysis of EBSD results indicated

that the model of grain occupation was not sufficient to explain the

microstructure variation across different species’ eggshells.

Defining the mechanism for compaction of chondritic asteroids using EBSD-derived microtexture P.W. Trimby1,2, L.V. Forman3, N.E. Timms3, J. Goulden1 and P.A. Bland3 1Oxford Instruments Nanoanalysis, High Wycombe, UK. 2The University of Sydney, Sydney, Australia. 3Curtin University, Perth, Australia

The Allende carbonaceous chondritic meteorite, falling in Mexico in

1969, is perhaps the most extensively studied meteorite in history.

However, there is still significant debate regarding the mechanism of

porosity reduction in the primitive parent body: possible models

include gravitational compaction, hot isostatic pressing (cold

compaction followed by radiogenic heating) or impact induced

compaction. All of these mechanisms would be expected to leave a

different microstructural signature, both in terms of local

deformation microstructures and microtexture.

In this study we used large area electron backscatter diffraction

(EBSD) mapping of a sample from the Allende meteorite to examine

local texture variations in the fine-grained olivine matrix between

large (~0.5 mm diameter) chondrules. Approximately 46 million

EBSD measurements were taken at a measurement spacing of 500

nm, covering an area of ~8 mm2. The exceptional statistics within

this dataset allowed us to subdivide the matrix regions into 120 100

x 100 m grid squares, thus constraining both local and regional

texture variations.

The texture in the matrix across the sample is moderately strong but

spatially heterogeneous, dominated by a preferred <100> axis

alignment with a coupled shape preferred orientation. In addition,

significant evidence exists for non-uniform crystal plastic

deformation at the margins of the chondrules. These observations

suggest that impact-induced compaction is the most likely

mechanism for compaction of the primitive parent body of the

Allende meteorite, and demonstrate the effectiveness of EBSD-

based texture measurements for determining the mechanisms of

asteroid and meteoroid formation.

Low-temperature EBSD investigations on a BaFe2As2 single crystal A. Pukenas1, P. Chekhonin1, M. Meißner2, E. Hieckmann2, S. Aswartham3, J. Engelmann3, B. Holzapfel4, S. Wurmehl3, B. Büchner3 and W. Skrotzki1

1Institut für Strukturphysik, Technische Universität Dresden, 01062 Dresden, Germany. 2Institut für Angewandte Physik, Technische Universität Dresden, 01069 Dresden, Germany. 3Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, 01062 Dresden, Germany. 4Institut für Technische Physik, Karlsruher Institut für Technologie, 76344 Eggenstein-Leopoldshafen, Germany.

The iron arsenide BaFe2As2 is one of the most studied high-

temperature superconductors [1]. On cooling, at TC ≈ 140 K the non-

doped BaFe2As2 undergoes a tetragonal-to-orthorhombic structural

and magnetic phase transition. The orthorhombic distortion leads to

the formation of structural domains which have been observed and

reported previously in polarized light microscopy and transmission

electron microscopy studies. However, these results are not

consistent with respect to the domain size.

A scanning electron microscope with a cryogenic sample holder was

combined with an electron backscatter diffraction technique to

achieve high spatial resolution (≤ 100 nm) and to avoid any

elaborated sample preparation prior to the analysis. The results

show domains with characteristic dimension of 0.1 μm up to few μm

and changes of domain pattern after a cooling-warming cycle.

[1] D.P. Chen & C.T. Lin (2014) Supercond. Sci. Technol. 27, 2.

ABSTRACTS TUESDAY AM - RECRYSTALLIZATION 42

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

Effect of recrystallization mechanisms on twin interconnectivity and corrosion resistance in FCC metals Asher C. Leff, Austin Nye, Ryan Demott, Matthew Hartshorne, & Mitra L. Taheri Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvannia, USA

Thermomechanical processing can be utilized in order to control the

grain boundary character of structural metals in order to optimize

performance. In particular, the generation of interconnected twin

and twin-related boundary networks has been shown to enhance

the properties of FCC metals. This study utilized in situ heating and

electron microscopy orientation mapping techniques at multiple

length scales in conjunction with the analysis of orientation data in

order to examine the evolution of twin-related domains in copper,

brass and stainless steel during recovery, primary recrystallization

and secondary recrystallization processes. Dislocation densities were

quantified using local misorientation analysis in order to determine

the driving force thresholds for these processes. Copper was chosen

as a model FCC material and 90/10 brass was used to examine how

substitutional solutes change the stored energy requirements for

the activation of various mechanisms. 316L steel was used to study

the effects twin-related boundary connectivity on intergranular

corrosion. Twin nucleation rates were found to be independent of

recrystallization rates regardless of solute content.

Evolution of recrystallization textures in Ni-Co alloys Gyan Shankar, Satyam Suwas

Department of Materials Engineering, Indian Institute of Science Bangalore, Bangalore, India

In spite of large number of studies, there is no general theory

dealing with the evolution of microstructure and texture during

recrystallization. The present work is aimed to develop a

comprehensive understanding of the effect of deformation

heterogeneities such as deformation bands, shear bands, twins etc.

on the recrystallized microstructure and micro-texture evolution in a

face centered cubic materials. Solid solubility of cobalt in nickel is

very high and in this system it is well known that stacking fault

energy of the alloy decreases with increase in cobalt content. It

leads to formation of shear bands and twined regions after

deformation. Ni-Co alloys with different Co were rolled to 90%

reduction in thickness and subsequently annealed above

recrystallization temperature. Textures were measured by SEM-

EBSD and X-ray diffraction. The results show that microstructure of

rolled Ni-60%Co comprises of deformation bands and twins,

whereas Ni-20%Co alloy deforms by normal slip. It was found that

recrystallization starts from the region of high deformation

heterogeneities. A detailed micro-mechanism of annealing texture

formation will be presented.

Effect of Sc and Zr Addition on Recrystallization Behavior and Texture formation in Al-Mg-Si alloy K. Ikeda and S. Miura Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, Japan.

In order to clarify the effect of scandium (Sc) and zirconium (Zr) on

recrystallization behavior and texture formation in Al-Mg-Si alloy,

microstructural observation was carried out by ex-situ and in-situ

heating SEM/EBSD methods. Al-0.5Mg-0.5Si-0.3Sc-0.2Zr (mass%)

alloy was cast, homogenized and hot-rolled at 673 K (Sample A).

Some specimens were intermediate annealed at 823 K for 6h after

hot-rolling (Sample B). And we prepared a cold-rolled Al-0.5 Mg-

0.5Si alloy (Sample C) to compare with Sample A and B. These

samples were cold-rolled into 1 mm thickness. According to previous

studies, it was found that there were many spherical and rod-like

particles, Al3(Sc, Zr), in hot-rolled sheets of Sample A. From the

results of in-situ heating SEM/EBSD analyses of Sample A, B and C, it

was found that the Al3(Sc, Zr) particles inhibited the normal grain

growth. Furthermore, the recrystallized grain sizes of these samples

were different: the grain size was large in order of Sample C, A and

B. From the viewpoint of texture formation, the annealed Sample C

had Cube and Goss orientation, while the annealed Sample A had no

preferential orientation. It was thought that Al3(Sc, Zr) can

controlled a grain size and texture of Al-Mg-Si alloys.

Evolution of micro-texture and microstructure during conventional sintering of copper N. Felege, N. P. Gurao, U. Anish Department of Materials Science & Engineering Indian Institute of Technology, Kanpur, 208016, India

Microstructural evolution of sintered materials is a well investigated

subject in powder metallurgy. However, the evolution of micro-

texture during sintering and its influence on mechanical properties

of the sintered material is not yet established. In the present

investigation the evolution of microstructure along with micro-

texture during sintering of commercially pure copper powder has

been studied. The powder was compacted using 300 MPa uniaxial

die pressure and the green compact was sintered in electric furnace

at 610 °C, 880 °C and 1020 °C in hydrogen atmosphere. The

temperatures were selected so as to obtain different dominant

densification processes comprising of grain boundary diffusion,

surface diffusion and volume diffusion respectively. Electron

backscatter diffraction indicated that there is a distinct evolution of

micro-texture and microstructure in terms of evolution of grain

boundary character distribution, misorientation and size, shape and

morphology of grains and pores. The sample sintered at 610 °C

showed a weak micro-texture unlike strong <101> fibre texture

obtained at other two temperatures indicating randomization of

orientations in the grain boundary diffusion dominated sintering.

The sample sintered at 1020 °C showed lower fraction of Sigma 3

ABSTRACTS TUESDAY AM - RECRYSTALLIZATION 43

boundaries with higher densification with rounded intergranular

pores, higher hardness and considerable grain growth indicating the

significant role of special boundaries in the sintering process.

ABSTRACTS TUESDAY AM - ENGINEERING 44

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Processing

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Texture Development of Alumina Coating Processed by Aerosol Deposition M. Hasegawa1, S. Sato1, M. Komuro1, K. Kimura1, M. Tanaka2, S. Kitaoka2, Y. Kagawa3 1Yokohama National University, Yokohama, Japan. 2Japan Fine Ceramics Center, Nagoya, Japan. 3The University of Tokyo, Tokyo, Japan.

Aerosol deposition (AD) method is a coating process that can

produce ceramic coatings by impacting solid particles onto a

substrate at room temperature under low-pressure conditions [1]. It

produces dense and crystalline coating without oxidation of

substrate at room temperature. The ability to form coatings up to

several micrometers thick without any heating is one advantage of

the AD method. These coatings are considered to be fabricated by

fracture and/or plastic deformation of the particles. The coating

phenomenon is called room-temperature impact consolidation [1].

Recently, texture formation has been reported by yttria stabilized

zirconia (YSZ) and alumina coating [2, 3]. However, systematic

research on microstructure and texture evolution is still not

experimentally performed. In this study, microstructure and texture

evolution of alumina coating deposited by AD method is examined.

Alumina coatings is deposited on a mullite and molybdenum

substrate by changing the AD processes such as kinds of gas, gas

flow rate, distance between substrate and nozzle and the scanning

speed of the substrate. Alumina coatings are heat-treated from 1173

K ~ 1673 K for 1 h ~ 20 h. Microstructure observation and texture

measurement of the coating surface are done by SEM, TEM, EBSD

and XRD. The 1012, 1123, and 1126 diffracted X-ray intensities

were measured for alumina with a rhombohedral lattice. On the

basis of the obtained pole figures, the orientation distribution

function (ODF) was calculated using the arbitrarily defined cell (ADC)

method [4]. The volume fractions for the regions aligned within 15°

of the main component were calculated. Dense and crystalline

alumina coatings with the average grain size of ~ 5 nm are formed in

as-coated state. After heating the coating at 1673 K for 5 h or more,

the average grain size became ~ 300 nm. In as-coated state, fiber

texture where the (0001) plane of alumina is tilting approximately

15 degrees from the coating plane has observed. With the increase

in gas flow rate increases the volume fraction of the main

component. This texture may form by the activation of cross slips by

basal slip and pyramidal slip system of alumina during the impact of

powder to the substrate. After the heat treatment, (0001) plane of

alumina became almost parallel to the coating plane. Regarding the

ab initio methodology, it is reported that the (0001) plane is the

lowest in the surface energy. The crystal grains exist at the as-

coated coating surface and/or the grains reaching the coating

surface during grain growth under heating in which the (0001) plane

is parallel to the coating plane seem to increase preferentially to

reduce the energy of the coating formed.

Acknowledgement: This research was supported by the “Advanced

Low Carbon Technology Research and Development Program” from

the Japan Science and Technology Agency. The authors greatly

appreciate the grant.

[1] J. Akedo (2006) J. Am. Ceram. Soc. 89, 1834. [2] E. Fuchita, E. Tokizaki, E, Ozawa and Y. Sakka (2011) J. Ceramic

Society of Japan 119, 271. [3] M. Hasegawa, K. Akiyama, Y. Oki, M. Tanaka, S. Kitaoka and Y.

Kagawa (2016) Mater. Trans. 57, 1138. [4] K. Pawlik, J. Pospiech and K. Lüche (1991) Text. Microstruct. 14-

18, 25.

Transmission – EBSD on Ti/TiN Multilayer Thin-Films Tarang Mungole1, Bilal Mansoor2, Georges Ayoub2, 3, David P. Field4 1School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington USA. 2Mechanical Engineering Program, Texas A & M University, Doha, Qatar. 3Industrial and Manufacturing Systems Engineering Department, University of Michigan, Dearborn, Michigan USA

Metal-ceramic multi-layered thin film systems comprising of

alternating layers of Ti and TiN were fabricated using a physical

vapor deposition (PVD) technique on a p-type (100) Si wafer.

Samples with different period thicknesses of Λ = 20 nm, Λ = 10 nm

and Λ = 5 nm were produced. Films of pure Ti and pure TiN were

fabricated as reference samples. Automated transmission

backscatter diffraction (t-EBSD) performed in FEI Sirion scanning

electron microscope at an accelerating voltage of 30 KeV, spot size

of 6, working distance of ~ 3 mm and a tilt angle of ~ -35o produced

indexable Kikuchi patterns from pure Ti thin-films deposited at 550 K

having ~ 80 nm lateral grain size. Sample preparation involved

reactive ion-etching of the Si wafer substrate to create windows of

freestanding Ti thin-films. t-EBSD of Ti thin-films revealed existence

of {0001} basal texture. Texture information from the Ti/TiN multi-

layered thin-film composite via t-EBSD will be also be presented.

Inhomogeneities in strained epitaxial BaFe2As2 thin films P. Chekhonin1, J. Engelmann2, M. Langer3, B. Holzapfel3, C.-G. Oertel1 and W. Skrotzki1 1Institut für Strukturphysik, Technische Universität Dresden, Dresden, Germany. 2 Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, Dresden, Germany. 3 Institut für Technische Physik, Karlsruher Institut für Technologie, Eggenstein-Leopoldshafen, Germany.

Strained BaFe2As2 thin films have been grown by pulsed laser

deposition on MgAl2O4 spinel substrates using thin iron buffer layers

to achieve epitaxy. The microstructure was characterized in a

scanning electron microscope applying the high resolution electron

backscatter diffraction and the electron channeling contrast imaging

technique.

ABSTRACTS TUESDAY AM - ENGINEERING 45

Very small lattice rotations (≤ 0.2°) and strain inhomogeneities on

length scales of 100 nm or even below dominate the microstructure

[1]. Partially strain relaxed areas with in-plane dislocations were

observed in BaFe2As2. Additionally, the results indicated that the

iron buffer layer crucially affects the quality of the BaFe2As2 layer.

[1] P. Chekhonin, J. Engelmann, M. Langer, B. Holzapfel, C.-G. Oertel & W. Skrotzki (2015) Cryst. Res. Technol. 50, 891.

Strong, Ductile, and Thermally Stable Mg-Nb Nanolaminates Siddhartha Pathak1*, Marko Knezevic 2, Nenad Velisavljevic 3, Manish Jain 1, Nathan A. Mara 3, Irene J. Beyerlein 3 1Chemical and Materials Engineering, University of Nevada, Reno, NV . 2Mechanical Engineering, University of New Hampshire, Durham, NH. 3Los Alamos National Laboratory, Los Alamos, NM

In recent years two-phase nanolayered composites with individual

layer thicknesses varying from 200-300nm down to 1-2 nm have

been the subject of intensive study because of their unusual

physical, chemical and mechanical properties. For example, with

decreasing layer thicknesses (down to nanometer length scales) the

mechanical response of these nanocomposites becomes increasingly

interface dominated, and they exhibit ultrahigh strengths

approaching the theoretical limit for ideal crystals. Moreover, if the

constituent phases present large differences in strength, elastic

modulus and ductility, these multilayers give rise to new possibilities

for the deformation mechanisms and properties of the composite as

a whole. In this work we explore the possibility of synthesizing

multilayered composites where one constituent phase has a low

ductility, with a final goal of enhancing both the strength and

ductility of the system.

Using physical vapor deposition (PVD) techniques we synthesized a

hexagonal close-packed (HCP) – body-centered cubic (BCC) Mg-Nb

system (where twinning in Mg leads to its lack of ductility), over a

range of layer thicknesses ranging from 5 nm to 200 nm. Testing of

such miniaturized poses significant challenges. We utilize a

combination of nanoindentation, in-situ SEM compression testing of

micro-pillars, and in-situ SEM fracture toughness testing of 3 point

bend micro-beams containing these multilayered nano-composites

to evaluate their deformation mechanisms. Micropillar testing for

three different orientations, with the interfaces oriented normal,

parallel and oblique (45o) to the compression axis, enable us to

explore the anisotropy in the mechanical response of the multilayer

system, while the fracture toughness of the specimens are

measured using the notched 3-point bend tests. These results are

compared for varying layer thicknesses as well as under varying

ambient temperatures.

Additionally, our work shows that at low enough layer thicknesses

the crystal structure of Mg can be transformed and stabilized from

simple hexagonal (hexagonal close packed hcp) to body center cubic

(bcc) at ambient pressures through interface strains. We show that

when introduced into a nanocomposite bcc Mg is far more ductile,

50% stronger, and retains its strength after extended exposure to

200 C, which is 0.5 times its homologous temperature. These

findings reveal an alternative solution to obtaining lightweight

metals critical needed for future energy efficiency and fuel savings.

Evolution of microstructure texture and mechanical behaviour of CoCuFeMnNi high entropy alloy subjected to high pressure torsion Reshma Sonkusare1, A. Kilmametov2, M. Palit2, 3, Krishanu Biswas1, N.P.Gurao1 1Indian Institute of Technology, Kanpur, India. 2Institute of Nanotechnology, Karlsruhe Institute of Technology, Germany. 3Defence Materials Research Laboratory, Hyderabad, India.

A newly developed face centre cubic single phase equiatomic

CoCuFeMnNi high entropy alloy, produced by vacuum arc melting

technique, was subjected to High Pressure Torsion (HPT). A

hydrostatic pressure of 5 GPa was applied and the thin disk

specimen were subjected to rotations of 0.1, 0.5, 1 and 5 turns.

Electron Backscatter Diffraction (EBSD) carried out at the centre of

the discs shows twinning in half turn sample and shear bands in five

turn sample. Transmission electron microscopy of the discs at the

periphery showed significant grain refinement while texture

measurement carried out at three different locations on the disk

(center, near the periphery and one between the two) using a micro-

focus X-ray source showed characteristic shear

texture.Developmentof the texture was analyzed in terms of shear

texture evolution in pure face centre cubic metals. X-ray diffraction

analysis shows the peak broadening as the number of turns

increases, without any phase transformation. Vickers hardness

reveals that hardness increases from the center of the disk to

periphery due to increase in shear strain. A correlation between

grain size, texture and hardness has been established for the newly

developed high entropy alloy. Instrumented micro-hardness tests at

different loading rate indicates an increase in activation volume with

decreasing grain size indicating the similarity in the behaviour of

single phase high entropy alloy and conventional body centre cubic

materials.

ABSTRACTS TUESDAY AM - CHARACTERIZATION 46

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National Laboratory

Evaluation of texture using laser-ultrasonics – application to steel processing B. Hutchinson*, P. Lundin. E. Lindh-Ulmgren and P. Bate Swerea KIMAB, Box 7047, SE-16407, Kista, Sweden

The aim of this work is to develop a methodology for accessing

texture information from metals during processing, in particular

during the hot rolling of steels. This implies making measurements

on fast moving surfaces and at temperatures up to or exceeding

1000°C. The only way this can be done is with laser-ultrasonics

where instrumentation is remote from the hot metal. Texture gives

rise to elastic anisotropy and this affects the velocity of ultrasonic

waves, which can be measured with high precision. Additionally,

grain sizes can be determined from the attenuation of the ultrasonic

wave signals.

A method has been developed whereby wave velocities can be

measured in different directions through the metal plate using only

a single laser shot. These results are compared in the first stage with

predictions based on known textures, employing Voigt-Reuss-Hill

averaging of the elastic tensor. Good agreement is obtained

between predicted and measured wave velocities along different

directions in the material.

The second, more challenging, stage involves inverse modelling in

order to calculate textures from the measured signals. A finite

difference method has been developed to model the complete

signal of wave arrivals and this is applied to a range of presumptive

textures with various combinations of the harmonic coefficients C411,

C412 and C4

13. These modelled spectra are then compared with the

experimental signals using a cross-correlation procedure and the

interpolated optimum solution is found.

This approach will be presented together with examples of its

application to material tests at ambient and elevated temperatures.

Dynamical Simulations of Transmission Kikuchi Diffraction Patterns and Related Diffraction Modalities E. Pascal1, S. Singh2 and M. De Graef2 1University of Strathclyde, Glasgow, Scotland. 2Carnegie Mellon University, Pittsburgh, USA.

The size of the interaction volume in the conventional electron

backscatter diffraction (EBSD) geometry poses a limiting factor to its

resolution. This size volume can be reduced by the use of an

electron transparent sample and the acquisition of EBSPs in

transmission mode. Transmission Kikuchi diffraction (TKD) patterns

are typically acquired by mounting the thin foil, and tilting it at a

slight angle (20°-30° from horizontal) towards a standard EBSD

camera. Alternatively, a dedicated detector can be mounted

horizontally below the sample, in which case the coherent

diffraction spots will also be intercepted by the camera. The

majority of the electrons contributing to a TKD pattern originate

from the bottom portion of the sample; they are generated by

elastic scattering of electrons that were inelastically (Rutherford)

scattered before reaching the bottom portion of the foil. A realistic

TKD simulation requires that the electron energy and directional

distributions properly be taken into account; these can be

determined using Monte Carlo trajectory simulations.

We use the Bloch wave formalism to compute the electron yield as a

function of crystallographic direction in the form of a thickness

integration over the product of the modulus-squared of the wave

function (as determined from dynamical scattering simulations) and

a weighting function, 𝜆(𝐸, 𝑧), that depends on the energy, 𝐸, of the

electron as well as the effective depth, 𝑧, of its last Rutherford

scattering event. If the range of effective depth values is sufficiently

narrow, then one can employ a master pattern approach, in which

an averaged depth profile is substituted in the integration and the

dynamical simulation is carried out for all incident beam directions

distributed on the unit sphere. If the effective depth range is not

narrow, then the master pattern approach is no longer possible, and

a full (time consuming) depth and energy integration must be used

for each detector pixel.

In this contribution, we will illustrate both cases in detail. We begin

with a brief description of the implementation of the energy- and

depth-weighted dynamical scattering expression and illustrate the

similarities and differences between EBSD, ECP (Electron Channeling

Patterns), and TKD; all three modalities essentially use the same

mathematical model. Then we illustrate the realism of the pattern

simulations by comparisons with experimental patterns on a

number of material systems. Along the way, we illustrate the use of

the master pattern for a fast computation of individual diffraction

patterns. We will discuss the implementation of these simulations

in the open source EMsoft package. We will conclude this

contribution with a description and preliminary results of a more

exact (and more time consuming) implementation in which we

determine, for each detector pixel, the energy and depth

distributions of the electrons and use those to properly weight a

dynamical scattering simulation to obtain the depth- and energy-

averaged intensities. This slower approach allows for the simulation

of band contrast inversions which occur when the effective depth

distribution becomes broad; in such cases, a significant number of

electrons is generated deep inside the sample, and the dynamical

scattering processes (in particular for bands with short extinction

distances) will cause changes from the normally bright Kikuchi band

intensity profiles to dark bands on a brighter background.

Texture determination using elastic waves for HCP and cubic materials Bo Lan, T. Ben Britton, Michael J.S. Lowe, Fionn P.E. Dunne Imperial College London, Exhibition Road, London, SW7 2AZ, United Kingdom

Crystallographic texture in polycrystalline HCP and cubic materials,

often developed during thermo-mechanical deformations, has

ABSTRACTS TUESDAY AM - CHARACTERIZATION 47

profound effects on various properties at the macroscopic or

component level. Currently widely-used texture detection

techniques, e.g. EBSD, X-ray or neutron diffraction, all have their

limitations, and a cost-effective, lab-based, non-destructive

technique for three-dimensional bulk texture detection has been

elusive. This talk aims introduce a new technique that achieves this

goal utilising elastic (compressional and shear) waves.

This study is based on the theoretical platform [1] previously

introduced by the authors, which demonstrated that the three-

dimensional wave speed variations in a homogeneous

polycrystalline aggregate could be written as the spherical

convolution between texture and single crystal wave speed surface,

thus enabled inverse texture extractions from polycrystal wave

speed measurements. This talk extends the study by establishing a

lab-based platform using the conventional water-bath ultrasonic

scanning system, for accurate measurements of polycrystal wave

speed variations and hence bulk texture. The technique is capable of

delivering important texture information that informs properties

such as elasticity, thermal expansion, magnetism etc for polycrystals.

However, there are two cases where texture information is not

accessible: (1) the extracted ODF is theoretically limited up to 4th

order truncation to the harmonic expansion of the original function;

(2) in HCP materials, such as Ti and Zr, only the (0001) pole figure is

achievable given the transverse (elastic) isotropy of its single crystal.

A range of industrially important materials have been examined,

including CP Ti, CP Zr, Zircaloy 4 (all pure HCP), Ti-6Al-4V (near alpha

HCP), 304 and 316 (austenitic-FCC), and 430 (ferritic-BCC) stainless

steels. By using the compressional wave results only, one can

recover the pole figures for single-phased materials and the majority

phase in dual-phased material, and estimate the alpha-beta phase

compositions for the latter. These results are calibrated against the

well-established neutron diffraction technique with the

conventional setup using monochromatic beams and Euclidian

cradle, and they agree well with the diffraction results across the

wide spectrum of materials.

We have also extended the convolution theory to shear waves as

well, and the interaction between shear wave and texture unlocks

the possibility of measuring the texture in the second phase in a dual

phase material (e.g. duplex stainless steel, Ti6246) too. We believe

this package of elastic wave development can provide valuable

texture information to a broad range of applications in metal,

mineral and geology studies.

[1] B Lan, MJS Lowe, FPE Dunne, J Mech Phys Solids, 83, 2015 (2 articles).

On-axis Transmission Kikuchi Diffraction in the SEM. Performances and Applications E. Bouzy1,2, E. Brodu1,2, J.-J. Fundenberger1,2 1Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux (LEM3), UMR CNRS 7239, Université de Lorraine, 57045 Metz, France 2Laboratory of Excellence on Design of Alloy Metals for low-MAss Structures (DAMAS), University of Lorraine, 57045 Metz, France

TKD (Transmission Kikuchi Diffraction) is a recent technique [1] of

orientation mapping in the SEM. Via the use of thin electron-

transparent samples, it allows reaching a spatial resolution of the

order of a few nanometers, whereas the resolution of the EBSD

technique on bulk samples is a few tens of nanometers. A new

configuration for the TKD technique has been proposed and

validated at LEM3 [2]. Overall, this new configuration allows

producing orientation maps with an improved spatial resolution and

also in less time in comparison to the initial configuration.

With this new configuration, the detector is set beneath the sample

in a horizontal position instead of being in a vertical position like in

the usual configuration. Also, it is centered in the transmitted beam

direction, which is why this configuration is called on-axis TKD.

Because the electrons which contribute to the formation of the on-

axis diffraction patterns are scattered at low angle, their intensity is

the highest. It allows to acquire orientation maps faster or/and with

a lower electron beam intensity in comparison to usual TKD. It has

been established that an electron dose twenty times lower is

sufficient to obtain diffraction patterns of the same quality. In

addition, it is possible to access a higher lateral resolution by

reducing the electron beam size via a current reduction and by using

very thin samples.

Taking into account the advantages of this technique, there are two

fields of application. The first is the field of the materials with

ultrafine grains or nanometer-sized for which the EBSD technique

fails. The other is the field of electron damage sensitive materials for

which it is necessary to use low dose electron beam. Many examples

taken from these two fields of application will be shown and

analyzed.

[1] R. R. Keller, R. H. Geiss J. of Microscopy (2012) 245, 245-251. [2] J.- J. Fundenberger, E. Bouzy, D. Goran, J. Guyon, H. Yuan, A.

Morawiec (2016) Ultramicroscopy 161, 17–22.

Microtexture and Local Anelasticity Measurements: Uncharted Possibilities K.S. Thool1, A.S. Panwar1, K.V. Manikrishna2, D. Srivastava2 and I. Samajdar1 1Indian Institute of Technology, Mumbai, India. 2Bhabha Atomic Research Centre, Mumbai, India

Dynamic mechanical analysis (DMA) has been used to measure

internal friction and even stipulated [1] to represent residual

stresses. In the past, such measurements were ‘bulk’ in nature. The

advent of nano-dma (dynamic mechanical analysis), and the ability

to estimate local anelasticity at different frequencies, provide

interesting possibilities. Experimental measurements on anelasticity

depend on the crystallographic orientation, defect structure and the

state of residual stress. Experimental nano-dma plus microtexture

measurements, with appropriate molecular dynamics (MD)

simulations, can decouple these factors. The combination may thus

provide a potential (and niche) platform for microstructural study.

This has been the objective. Commercial single-phase zirconium was

subjected to controlled plastic deformation. Relatively minor tensile

strains were shown to enforce significant strain localizations,

especially in terms of near boundary mesoscopic shear strains [2].

Nano-dma was shown to capture the microstructural perturbations,

ABSTRACTS TUESDAY AM - CHARACTERIZATION 48

and more importantly to provide clear possibilities for estimating

developments in local residual stresses.

[1] C. Zener (1937) Phys. Rev., 52, 230. [2] N. Keskar, S. Mukherjee, K.V. Mani Krishna, D. Srivastava, G.K.

Dey, P. Pant, R.D. Doherty, I. Samajdar (2014) Acta Mater., 69, 265.

ABSTRACTS TUESDAY PM1 - PLENARIES 49

TUESDAY PM PLENARY SESSION

Evolving deformation structures: high-resolution reciprocal space mapping and orientation distribution of individual grains W. Pantleon Section of Materials and Surface Engineering, Department of Mechanical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.

During plastic deformation of polycrystals, grains of initial unique orientation develop an intrinsic orientation spread due to trapping of dislocations

in dislocation boundaries. The deformation structures cause subdivision of individual grains into subgrains and increasing orientation differences

between the latter. A unique method, high-resolution reciprocal space mapping, is presented by which the evolution of subgrain structures can be

monitored in-situ during varying loading conditions with high-energy synchrotron radiation. By mapping a single diffraction peak from an individual

grain in a polycrystals with high resolution three-dimensionally in reciprocal space repeatedly during the deformation process, individual subgrains

can be identified by their unique orientation and followed during deformation; new insights in the development of the deformation structures are

gained from their elastic strains and the developing orientation differences. In this manner, at most an azimuthal projection can be obtained

analyzing a single diffraction peak and only part of the orientation spread within a grain can be resolved. In-situ investigations of the developing

deformation structures are therefore complimented by post-mortem characterization of the deformation structures with electron backscatter

diffraction. The essential information gained from the local orientations, their spatially heterogeneity and the advanced possibilities for

characterizing the micro orientation distribution function of individual grains in deformed microstructures are discussed.

Local Curvature Multi-Vertex Grain Growth Model and Its Application T. Tamaki and K. Ushioda Nippon Steel & Sumitomo Metal Corporation, Chiba, Japan.

Steel is used in many fields such as vehicle, railroad, energy, architecture, machine, and so forth. In recent years the higher performance has been

increasingly required from the points of environmental conservation and security commitment issues. Steel is the polycrystalline material, whose

grain size, grain size distribution and texture have a significant effect on properties of the material. Therefore, it is very important to predict and

control the grain size, grain size distribution and texture in order to produce the high quality material.

In the presentation, focus is placed on the change in microstructure and texture during the normal and abnormal grain growth of metallic

materials. The aim is to elucidate the mechanism of grain growth and texture formation in steel. The following approaches have been performed.

First, the two-dimensional local curvature multi-vertex model, which is the physical and direct model for grain growth, has been proposed. A

simulator has been manufactured based on the proposed model, and the validity of the proposed model has been proved.

Next, in order to investigate the mechanisms on the evolution of microstructure and texture during grain growth of steel sheet, the two-

dimensional local curvature multi-vertex model was applied to the normal grain growth of actual steel sheets for examining the effect of the

respective misorientation dependencies of grain boundary energy and mobility on grain growth in comparison with experimental results. The

simulation result revealed that the grain boundary energy had a major influence on the change in misorientation distribution with grain growth,

whereas the grain boundary mobility did not have such a large influence.

Finally, the meso-scale pinning model for grain boundary migration by one pinning particle has been proposed. This model is the physical model

that minimizes grain boundary energy as an evaluation function. In the presence of pinning particles, the models of normal grain growth and

abnormal grain growth by control of grain boundary energy have been established.

Additionally, the recent industrial application of texture control in various filed is presented in relation to the required performances.

ABSTRACTS TUESDAY PM1 - DEFORMATION 50

Symposium D: Deformation Textures Session: Titanium

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Effect of Texture on Anisotropic Deformation Behaviors in Cold-rolled and Annealed Pure Titanium Nahoko Saji1, Yu Bai1,2, Takahiro Kunimine3, Akinobu Shibata1,2 and Nobuhiro Tsuji1,2

1Department of Materials Science and Engineering, Kyoto University, Kyoto, Japan. 2Elements Strategy Initiative for Structural Materials (ESISM), Kyoto University, Kyoto, Japan. 3School of Mechanical Engineering, Kanazawa University, Kanazawa, Japan.

It is known that cold-rolled and annealed sheets of commercially

pure titanium, having hexagonal close-packed (HCP) crystalline

structure, show anisotropic deformation behaviors depending on to

which direction on the sheet plane the tensile deformation is carried

out. The purpose of the present study is to clarify the reason for the

anisotropic deformation of pure titanium. Cold-rolled and annealed

sheets of commercial purity titanium (JIS grade-1) with a thickness

of 0.5 mm and a mean recrystallized grain size of 28 m were used

as the coarse-grained specimens. The starting coarse-grained

titanium showed the typical recrystallization texture of pure

titanium indexed as {03-37}<2-1-10> where the [0001] c-axis is tilted

by 30-40° from the normal direction (ND) toward the transverse

direction (TD) of the sheet. Ultrafine grained (UFG) specimens with

a recrystallized mean grain size of 1.1 m were also prepared by

processing the starting sheets by the accumulative roll bonding

(ARB) followed by annealing. The UFG specimens also showed a

similar [0001]-tilted texture. The coarse-grained and UFG sheets

were tensile tested at room temperature, and both specimens

having different grain sizes exhibited totally different stress-strain

curves depending on the tensile direction: i.e., the specimens tensile

deformed along the rolling direction (RD) showed typical stress-

strain curves characterized by yielding, strain-hardening and necking

to failure, while the specimens deformed along TD showed higher

yield strength than the RD specimens, early necking and quite large

post-necking elongation. Different crystal rotation behaviors during

the tensile deformation were found depending on the tensile

directions after detailed EBSD analysis. Especially in the TD

deformed specimen, crystal rotation of the main texture resulted in

a crystallographic softening, i.e., an increase of Schmid factor for

prismatic slips. However, it was also clarified that the geometrical

softening is not only the reason for the early necking and large post-

necking elongation apparent on the stress-strain curves of the TD

specimens. Digital image correlation (DIC) analysis of the specimens

confirmed that the necking behaviors were totally different between

the RD and TD specimens, and the TD specimen certainly showed

early necking followed by diffuse necking. The reason of the

anisotropy will be discussed in terms of activation of deformation

twins and different kinds of slips in addition to the texture rotation,

which were all dependent on the tensile direction.

Effect of crystallographic texture on micro-mechanisms of deformation in monotonic and cyclic loading of titanium Subhasis Sinha, Atasi Ghosh, N.P. Gurao Indian Institute of Technology Kanpur, Kanpur-208016, India

Commercially pure hexagonal close packed titanium with less than

ideal c/a ratio was subjected to uniaxial tension and cyclic loading

for one cycle and multiple cycle till failure in stress control and strain

control mode. Samples with distinct initial texture characterized

with basal texture (c-axis along loading direction) and prismatic-

pyramidal texture (c-axis perpendicular to the loading axis) were

tested on a servohydraulic universal testing machine and subjected

to electron back scatter diffraction to study the evolution of

microstructure and micro-texture as a function of monotonic and

cyclic loading. Few select samples were subjected to in situ electron

back scatter diffraction to develop better insight into the operative

micro-mechanisms during monotonic and reverse loading. It was

observed that the sample with basal texture (c-axis along the

loading direction) showed higher yield strength and lower ductility

than the sample with c-axis normal to the loading direction in

monotonic tension. The former was characterized by single variant

extension twin while the latter was characterized by multi variant

extension and contraction twins. Cyclic loading test on the two

samples indicated an interesting trend with the sample with lower

monotonic ductility exhibiting higher cyclic life in strain control low

cycle fatigue but lower cyclic life in stress control test. Similar trend

was observed for the sample that exhibited higher monotonic

ductility and cyclic ductility in stress control mode but low cyclic

ductility in strain control mode. The cyclic samples showed

characteristics twins similar to that in tension albeit extremely thin

in load reversal (one cycle) and with moderate thickness in cyclic

samples loaded till failure. It is proposed that the nucleation,

propagation and lateral thickening of twins play an important role in

determining the monotonic and cyclic ductility of titanium.

Orientation with single variant twinning in monotonic tension and

stress control cyclic testing promotes lateral thickening of twins that

contributes to lower ductility while twin nucleation and propagation

contribute to strain hardening and facilitate detwinning in load

reversal contributing to higher monotonic and cyclic ductility

respectively. Elastoplastic self-consistent simulations were carried

out to quantify the operation of different slip and twin modes to

rationalize the experimental results.

ABSTRACTS TUESDAY PM1 - DEFORMATION 51

Microstructural Evolution of Ti-7Al Under Cyclic Loading R.E. Lim1, Y. Shen1, T. Ozturk1, C.A. Kantzos1, J.V. Bernier2, P.A. Shade3, R.M. Suter1 and A.D. Rollett1 1Carnegie Mellon University, Pittsburgh, USA. 2Lawrence Livermore National Laboratory, Livermore, USA. 3U.S. Air Force Research Laboratory, Dayton, USA.

High-energy x-ray energy diffraction microscopy (HEDM), which is a

synchrotron-based, non-destructive, 3-D characterization technique,

was used to track three-dimensional microstructural evolution in a

sample of -phase Ti-7Al under variable tensile load. Near-field

HEDM measures orientation on a 3-D grid which provides grain

morphology, while far-field HEDM measures the strain state of each

individual grain. Combined with digital image correlation (DIC) and

synchrotron-based x-ray micro-tomography (-XCT), we perform

grain-by-grain analysis to track strain evolution under cyclic loading.

The results show a decrease in residual elastic strain over the first

couple of cycles followed by an increasing build-up of strain. This will

be used in the future to model fatigue at the microstructural level

using full field micro-mechanical models.

About the combined role of texture and grain size on hardening behavior of cp titanium sheets F. Wagner1,2, T. Richeton1,2, C. Chen2 and L.S. Toth1,2 1LEM3 (UMR-CNRS 7239), Université de Lorraine, Ile du Saulcy, 57045 Metz-Cedex1, France. 2Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures (Labex Damas), Université de Lorraine, 57045 Metz-Cedex1, France

Titanium sheets of commercial purity were cold rolled up to 75% and submitted to various heat treatments. These treatments generated microstructures with different grain sizes. In few cases partially recrystallized states were also considered. Mechanical properties were determined from tensile tests. It appeared clearly that the grain size is an important characteristic for both the level of the yield stress and the amplitude of the hardening whereas the texture governs the anisotropy as evidenced from tractions along RD and TD. Post-mortem observations (i.e. after extension) showed a very limited twinning activity, the plastic deformation resulting mainly from the slips over the various slip systems according to the orientation of the grains as determined, before the tensile tests, from EBSD maps. To better explain the grain size effect, an elasto-viscoplastic self-consistent model based on the translated field method [1] was modified to incorporate grain size effects. These effects were taken into account in a phenomenological way by adding a grain size dependent contribution in the expression of the critical resolved shear stresses (CRSS). The various performed simulations permit to draw the following conclusions:

• the yield stress is strongly linked to the CRSS of the easiest slip system (prismatic slip system) and the grain size

• the anisotropy (RD and TD extension) results from the initial texture and the ratios of the CRSS of the different slip systems

• the hardening amplitude decreases with decreasing grain size because of the role of the grain boundaries acting as dislocation traps.

[1 K.E.K. Amouzou, T. Richeton, A. Roth, M.A. Lebyodkin, T.A. Lebedkina (2016), IJP, Vol. 80, p.222-240

ABSTRACTS TUESDAY PM1 – RUDY WENK 52

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

20 Years of Maud and the Rietveld Texture Analysis L. Lutterotti1, S. Matthies2 and H. -R. Wenk3 1Department of Industrial Engineering, University of Trento, Trento, Italy. 2Muller-Berset-Str. 3, 01309 Dresden, Germany. Department of Earth and Planetary Science, University of California at Berkeley, Berkeley, CA.

Traditionally the orientation distribution of a textured polycrystalline

material has been obtained from a limited number of more or less

complete pole figures. The method is practical for metals and alloys

or compounds with highly symmetrical space groups and few

diffraction reflections, but not for low symmetry geological materials

or composites where the high overlap makes it difficult to measure a

sufficient number of clean pole figures. The Rietveld texture analysis

(RTA) has been developed from a team lead by Rudy Wenk to

overcome such difficulties from the beginning of the nineties of last

century. After some years of developments and the first successful

trials on standard samples, he was again Prof. Wenk who advocates

for the necessity of writing a RTA tool by which everyone in the

scientific community could use the new method. The first version of

such tool, MAUD (Materials Analysis Using Diffraction), came out in

1997 [1]. Thanks to the constant work, testing and push of Rudy

Wenk the program and the RTA method has been matured to the

actual package in use by several laboratories around the world. It is

worth nothing now that there shouldn’t be a MAUD program

without Prof. Wenk. He has been always also the principal supporter

and tester, using it himself, proposing and supporting new

developments and pushing others to use it and the RTA. He has now

used it to obtain quantitative texture and microstructural

information of very complex geological materials like shales

containing up to 7 phases [2]. Not only, he has showed how to

measure texture using transmission images and the RTA [3] and

recently doing the same for high pressure experiments [4]. His

works, from instrumentation to methodology, analysis applications

and education, has permitted the RTA to develop and diffuse in the

scientific world and not remain a pure theoretical exercise.

[1] L. Lutterotti, S. Matthies, H. -R. Wenk, A. S. Schultz and J. W. Richardson, Jr. (1997) J. Appl. Phys. 81, 594.

[2] W. Kanitpanyacharoen, H. -R. Wenk, F. Kets, C. Lehr and R. Wirth (2011) Geophysical Prospecting 59, 536.

[3] H. -R. Wenk and S. Grigull (2003) J. Appl. Cryst. 36, 1040. [4] H. -R. Wenk, I. Lonardelli, J. Pehl, J. Devine, V. Prakapenka, G.

Shen, H.-K. Mao (2004) Earth and Planetary Science Letters 226, 507.

Texture Measurements by Neutron Time-of-flight Diffraction – a Powerful Tool Pioneered by Rudy Wenk S.C. Vogel1, E. Aydogan1, S. Takajo1,2, Y. Onuki3, T. Tomida4, L. Lutterotti5, and H.R. Wenk6 1Los Alamos National Laboratory, Los Alamos, NM, U.S.A. 2JFE Steel Corporation, Kurashiki, Japan. 3Frontier Research Center for Applied

Atomic Sciences, Ibaraki University, Ibaraki, Japan. 4Ibaraki Prefectural Government, Ibaraki, Japan. 5Department of Industrial Engineering, University of Trento, Italy. 6UC Berkeley, Berkeley, CA, U.S.A.

Neutron time-of-flight diffraction has become a routine tool for bulk

texture characterization with dedicated instruments at all pulsed

neutron sources. The first neutron time-of-flight diffractometer

specifically optimized for texture measurements was HIPPO at

LANSCE, with Rudy Wenk being Co-PI with Bob Von Dreele and

Kristin Bennett [1,2]. Commissioned in 2001, the instrument has

since been a work-horse for texture measurements for one and half

decades. In this contribution, we present the principles of neutron-

time-of-flight texture measurements and review some highlights of

the research conducted by Rudy Wenk. We propose an experimental

approach to measure the resolution in ODF space of a given

instrument. Finally, we report on a second texture round robin,

following Rudy Wenk's initial round robin on neutron texture

measurements [3]. The idea for this round robin originated from the

availability of full-pattern Rietveld refinements that allow to

combine texture analysis with crystal structure determination as

well as microstructure characterization, e.g. volume fractions of

ferrite and austenite in steels. We hope to be able to present first

results at the conference.

[1] K. Bennett, R. B. Von Dreele, & H. R. Wenk (1999) "HIPPO." a new high intensity neutron diffractometer for characterization of bulk materials, in “Proc. ICOTOM-12”, JA Szpunar, Ed. NRC Research Press, Ottawa, Canada, 129-134.

[2] K. Bennett, R. B. Von Dreele, & H. R. Wenk (1999) "‘HIPPO'-A New High Intensity Neutron Diffractometer for Bulk Analysis of Materials." IUCr Newsletter 22, 6.

[3] H.-R. Wenk (1991) "Standard project for pole-figure determination by neutron diffraction." Journal of Applied Crystallography 24, 920-927.

ABSTRACTS TUESDAY PM1 – RUDY WENK 53

Principles of ice dynamics during crystal-plastic deformation: Linking texture, rheology and average grain size S. Piazolo1,2,, D. Cyprych1, C.L. Wilson3, Vladimir Luzin4, Mark Peternell 5 1 Australian Research Council Centre of Excellence for Core to Crust Fluid Systems/GEMOC, Department of Earth and Planetary Sciences, Macquarie University, NSW 2109, Australia. 2School of Earth and Environment, University of Leeds, UK. 3School of Geosciences, Monash University, Clayton, Victoria, 3800, Australia. 4ANSTO Locked Bag 2001, Kirrawee DC, Lucas Heights, NSW 2232, Australia. 5Department of Earth Sciences, University of Mainz, 55099 Mainz, Germany.

Prediction of glacier and polar ice sheet dynamics is a major

challenge, especially in view of changing climate. The flow behaviour

of an ice mass is fundamentally linked to processes at the grain and

subgrain scale. However, our understanding of ice rheology and

microstructure evolution based on conventional deformation

experiments, where samples are analysed before and after

deformation, remains incomplete. To close this gap, we combine

deformation experiments with in-situ neutron diffraction to monitor

continuously the evolution of texture, average grain size and

rheology.

We prepared ice samples from deuterium water, as hydrogen in

water ice has a high incoherent neutron scattering rendering it

unsuitable for neutron diffraction analysis. In experiments we

deform initially randomly oriented polycrystalline ice at three

different temperatures and two different strain rates. Textural

development shows a general change from a weak single central c-

axis maximum to a strong girdle distribution at 35° to the

compression axis. Dislocation-related hardening accompanies this

switch and is followed by weakening due to new grain nucleation

and grain boundary migration. With decreasing strain rate and

increasing temperature, grain boundary migration becomes

increasingly dominant and texture more pronounced. This goes

hand in hand with different stress-strain behaviour in particular

systematic differences in peak and steady-state stress values.

Our observations highlight the links between dynamics of

competition of deformation-related processes, texture development

and rheological behaviour. This link needs to be taken into account

to improve ice mass deformation modelling critical for the

prediction of climate change consequences. Our results show that

neutron diffraction textural and grain size analysis combined with in-

situ experiments represents a powerful tool to investigate the

dynamics of ice.

Microscopic study of texture evolution under tensile strain: slip events in zirconium resolved in 3D R. Chen,1 W. Chen,1 J. Lind,2 A. D. Rollett,1 and R. M. Suter1 1Carnegie Mellon University, Pittsburgh, PA USA. 2Lawrence Livermore National Laboratory, Livermore, CA USA.

Non-destructive, three dimensionally resolved measurements of

lattice orientation are used to image rotations associated with slip

events during plastic deformation of a zirconium polycrystal. Near-

field High Energy X-ray Diffraction Microscopy has been used to

perform the measurements during tensile deformation up to 17%

true strain. The measurements were carried out at the 1-ID

beamline at the Advanced Photon Source. In lower symmetry

materials such as hexagonal close-packed zirconium, it is

straightforward to link intra-granular rotations to single slip systems

by characterizing the variations in rotation axis and angle

corresponding to individual events. We perform voxel-by-voxel

searches for appropriate orientation discontinuities within grains. In

prior work we characterized twin formation; here, we extract

prismatic slip events which are favored by the anisotropic texture of

the sample. Similar searches for basal events yielded no events. The

lattice orientation discontinuities are observed to form low angle

interfaces within what were previously highly ordered crystalline

grains. The degree to which these rotations occur on expected

crystallographic planes and the variations in rotation angle and axes

within these planes can be characterized. The results of this analysis

are compared to 3D FFT based visco-plastic simulations that use the

initial measured microstructure as input. Initial correlation of the

computed lattice rotations with the observed lattice rotations is

encouraging.

ABSTRACTS TUESDAY PM1 - RECRYSTALLIZATION 54

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

Preferred orientation formation in Al-3mass%Mg subjected to shear deformation and subsequent annealing Y. Takayama, T. Kanamaru, K. Wachi and H. Watanabe Utsunomiya University, Utsunomiya, Japan,

Shear deformation is imposed on materials by several advanced

techniques for microstructural and textural control. Shear texture

evolved during deformation tends to remain after subsequent

annealing. Preferred orientation formation with shear deformation

and annealing in Al-3mass%Mg alloy rolled sheet has been

investigated by SEM/EBSD technique. S-shaped specimen was

prepared from the alloy sheet to impose shear strain in

compression. The central objective part of the S-shaped specimen

was sheared with rotation about the normal axis so as to develop

preferred orientations of {111} parallel to the original shear plane

and <110> parallel to the original shear direction before

deformation. In-situ EBSD analysis revealed that the preferred

orientations formed by shear deformation remain and evolve as

recrystallization texture during subsequent annealing. The evolution

of the shear recrystallization texture depended obviously upon

sample direction parallel to shear direction.

Microstructure and Texture Evolution in Pulsed Electrodeposited Nanotwinned Copper Rohit T. Mathew and M.J.N.V. Prasad

Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, INDIA.

Highly textured nanotwinned copper foils were fabricated using

pulsed electrodeposition from an additive-free acidic copper

sulphate bath. The evolution of grain structure and crystallographic

texture of electrodeposited nanotwinned copper is investigated as a

function of electrodeposition parameters such as substrate material,

duty cycle and peak current density. The use of pure Ti (HCP), IF

steel (BCC), SS304 (FCC) or nanocrystalline Ni-P alloy (FCC) as

cathode during electrodeposition led to formation of differently

oriented nano-twins and varying density of growth-twins in Cu foils

with dominant {111}, {100} or {110} type fiber texture. A similar

trend in change of crystallographic texture was also observed in Cu

foils deposited at different pulse duty cycles at constant peak

current density. Electrodeposition of copper on Ti substrate showed

a strengthening of {111} fiber texture with increasing peak current

density. This texture change was also accompanied with grain

refinement and occurrence of columnar grain structure containing

high density of nanotwins of uniform twin lamella thickness of ~50

nm parallel to the substrate surface. These microstructural

developments are correlated with the stability of growing planes,

interfacial energies and preferred diffusion directions in FCC

materials. Nanoindentation and tensile deformation studies showed

that the mechanical behavior of the as-deposited Cu foils is affected

significantly due to their different microstructures and texture.

Characteristics of Thin Cu Films Electrodeposited on Textured Ni Co Substrates B. Panda1 and R. K. Ray2 1CMR Institute of Technology, Bangalore, India. 2MN Dastur School of Materials Science and Engineering, IIEST Kolkata,India

An attempt has been made to study the effects of current density

and the texture of the underlying substrate on electrodeposited

copper. For this purpose, five Ni-Co alloys, Ni-10 Co, Ni-20 Co, Ni-30

Co, Ni-40 Co and Ni-60 Co, in the cold rolled as well as in the

annealed conditions, were used as substrates. Acid copper sulfate

solution was used to deposit thin Cu layers on the substrates, using a

Cu plate as anode, at four different current densities, 1, 10, 30 and

50 mA/cm2

The thickness of the electrodeposited Cu layer increased nearly

linearly with current density, but was independent of the texture

and composition of the underlying substrate. In general, the X-ray

diffraction line intensities for the deposited Cu layer sharpened and

those for the substrate Ni alloys weakened with increase in current

density. The textural developments in the Cu deposits appeared to

be quite independent of the textures as well as the compositions of

the substrate materials. The deposited Cu layers did not inherit the

textures of the substrates at the lower current densities, and also

developed their own textures at higher current densities. The Cu

(220) peak ultimately became the strongest XRD peak for the

electrodeposited layer. The grain sizes of the deposited Cu layers

decreased with increasing current density, quite independent of the

substrate texture. The surface roughness of the deposited layers was

distinctly smoother for the annealed substrates, as compared to the

cold rolled Ni-Co alloys.

Fabricating Designed Crystallographic Textures through Heterogeneous Templated Grain Growth D.J. Frandsen, O.K. Johnson Brigham Young University, Provo, United States

Microstructure sensitive design (MSD) is a theoretical framework

that permits the identification of microstructures with optimized

engineering performance. However, fabrication of these designed

microstructures is limited by current manufacturing methods. In this

talk, we describe a new materials processing route called

Heterogeneous Templated Grain Growth (HTGG), which may assist

in bridging the gap between simulation and fabrication of designed

crystallographic textures.

ABSTRACTS TUESDAY PM1 - ENGINEERING 55

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Materials

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Influence of equal channel angular pressing temperature on texture in pre-extruded AX41 magnesium alloy

M. Janeček1, T. Krajňák1,2, P. Minárik1, J. Stráská1, J. Gubicza3, K.

Máthis1 and R. Kužel1 1Charles University in Prague, Prague, Czech Republic. 2Slovak Academy of Sciences, Bratislava, Slovakia. 3Eötvös Loránd University, Budapest, Hungary.

Pre-extruded AX41 magnesium alloy was severely deformed by

equal channel angular pressing up to 8 passes at temperatures of

220 °C and 250 °C. The influence of temperature of processing on

the crystallographic texture was investigated by means of electron

backscatter diffraction (EBSD) and X-ray diffraction. The original

fiber texture formed after extrusion is gradually transformed into

two strong texture components with increasing number of ECAP

passes. The intensity of these components was found to be affected

by the temperature of processing. Based on the post-mortem

analysis of Burgers vector population, a model describing the texture

evolution during ECAP processing was proposed.

Texture development in soft ferromagnetic Fe-Co-2V processed by Equal Channel Angular Extrusion (ECAE) J.R. Michael1, A.B. Kustas1, D.F. Susan1, I. Karaman2 and T. Jozaghi2

1Sandia National Laboratories, Albuquerque, NM, USA. 2Texas A&M University, College Station, TX, USA.

The 48Fe-48Co-2V alloy, also known as Hiperco® 50A, is a soft

ferromagnetic material used in electric motor and solenoid

applications. While this alloy has remarkably high permeability and

the highest saturation induction of all soft magnetic alloys, the poor

mechanical properties and workability are problematic. Recently,

equal channel angular extrusion (ECAE) was used to process

Hiperco® and improve these properties. However, the effects of the

ECAE processing on the corresponding crystallographic textures,

important to magnetic properties, have yet to be considered. In this

study, textures in Hiperco® following ECAE are characterized.

Textures are obtained from specimens processed via routes C and E

at high deformation temperatures (T = 750 – 850 °C). Route C is

shown to develop a classical shear texture, defined by partial {110}

and <111> fibers, while route E developed a strong <111>

orientation in the extrusion direction. These textures are discussed

in relation to the differences in the processing route and compared

to those of commercial Hiperco® bar and sheet material. Potential

implications of the ECAE textures on the structure-sensitive

magnetic properties are also discussed.

® Hiperco is a tradename of Carpenter Technology Corp., Reading, PA

Sandia is a multi-mission laboratory operated by Sandia Corporation,

a Lockheed Martin Company, for the United States Department of

Energy’s National Nuclear Security Administration under contract

DE-AC04-94AL85000.

Texture evolution in extruded AX41 magnesium alloy severely deformed by equal channel angular pressing via routes A, Bc and C T. Krajňák1,2, P. Minárik1, J. Gubicza3, K. Máthis1, R. Kužel1 and M. Janeček1 1Charles University in Prague, Prague, Czech Republic. 2Slovak Academy of Sciences, Bratislava, Slovakia. 3Eötvös Loránd University, Budapest, Hungary.

The influence of three different equal channel angular pressing

(ECAP) routes (A, Bc and C) on the crystallographic texture

development in the pre-extruded AX41 magnesium alloy was

investigated using electron backscatter diffraction (EBSD). The

microtexture evaluated from EBSD was correlated with the

macroscopic crystallographic texture determined by X-ray

diffraction. The texture of ECAP processed samples was found to be

significantly influenced by the processing route. In all samples, two

main texture components were formed. However, their intensities

vary for the different ECAP routes. X-ray line profile analysis was

employed to examine the distribution of dislocations in the

particular slip systems. Moreover, a model describing the texture

evolution during ECAP processing taken into account different

activation of the basal and the second order pyramidal slip systems

was proposed.

The nucleation of cube grains during primary recrystallization of aluminium M.M. Miszczyk, H. Paul Polish Academy of Sciences, Institute of Metallurgy and Materials Science, Krakow, Poland

The influences of microstructure and texture on the cube grain

formation during early stages of recrystallization of a commercial

AA1050 alloy and pure Al single crystal of S{123}<634> orientation

have been characterized. Samples of AA1050 alloy were deformed

along two deformation modes to form different as-deformed

texture components and then lightly annealed: one group was plane

strain compressed (PSC) in a channel-die, whereas the second group

was deformed by equal channel angular extrusion (ECAE). The

results obtained on polycrystalline AA1050 alloy were compared

with recrystallization behavior of PSC single crystals of different

variants of S orientation which is stable up to 40% of PSC. The

textures were measured by X-ray diffraction and SEM/EBSD. After

both deformation modes a very weak residual cube texture

component was observed in the samples of AA1050 alloy. Cube-

oriented grains were not formed during annealing of the ECAE

samples whose main as-deformed texture components were close

to {124}<651>. During recrystallization these transformed to two

components of ~{100}<011> and ~{221}<114>-type essentially by

ABSTRACTS TUESDAY PM1 - ENGINEERING 56

<110> rotations. Cube grains were extensively formed during

annealing of PSC of S-oriented single crystals and AA1050 alloy

samples. In polycrystalline samples they were situated preferentially

inside or in between the S-oriented deformed areas with local

disorientations about <111> axes.

ABSTRACTS TUESDAY PM1 - CHARACTERIZATION 57

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National Laboratory

The contribution of EBSD to texture studies over the past 30 years David J Dingley University of Bristol, Bristol UK

It is thirty years since the first paper describing the collection and

presentation of orientation data using the Electron Backscattering

technique was presented at an ICOTOM meeting. Other emerging

techniques presented at that meeting were automated transmission

electron microscopy, synchrotron x-ray radiation, neutron

diffraction and an energy dispersive x-ray detector system. Over the

following decade use of the EBSD technique expanded rapidly

though many of the papers were more concerned with proving the

reliability of the technique by comparison with x-ray diffraction

results than with exploring the fundamental advantage of the

technique. Its greatest advantage over all others is that it provides

both macroscopic texture and microscopic texture presented in the

form of orientation maps. Less obvious was the fact that EBSD

removed at a stroke the uncertainties, the so called ghost problem,

when calculating the orientation distribution function from

individual pole figure data as obtained from x-ray Laue patterns.

Because it enabled the construction of misorientation maps the

emphasis switched to studies of the role of grain boundaries in

texture determination which in turn led to boundary plane

determination and the emergence of serial sectioning and 3D

mapping. Misorientation measurements between neighbouring

points within grains provided a first glimpse of residual deformation

and internal dislocation structures. By 2005, nearly twenty years

after the first paper, texture measurements using EBSD was the

norm and the applications widespread. At the same time

techniques for quantitative strain measurements were becoming

viable and by 2006 the first paper describing a viable method was

published under the title High Resolution EBSD. Just as in the early

years of EBSD the first HR EBSD studies concentrated on proving its

robustness with consequent improvements in data acquisition and

analytical techniques following on. And, as was the case with

standard EBSD, the impact of this technique in advancing our

understanding of texture development and identifying the critical

factors within the deformation structure that control and define the

state of the material, are slowly becoming clearer.

Denoising of EBSD Data R. Hielscher1, C. Silbermann1 and E. Schmidl1 TU Chemnitz, Germany.

Individual orientation measurements in EBSD maps are often

affected by measurement errors. These measurement errors are

especially troublesome if local orientation changes are investigated,

e.g. by means of kernel average misorientation (KAM) or

geometrically necessary dislocation density (GND). The accuracy of

individual orientations measurements can be improved by either

applying better indexing algorithms, e.g., cross-correlation methods,

or by applying denoising techniques.

In our talk we first investigate the impact of the noise level to the

computed KAM and GND values. Next, we compare well known

denoising algorithms, like mean and median filters, with newly

developed methods based on spline approximation and half

quadratic optimization. The new denoising methods are proven to

dramatically increase the accuracy of the determined KAM and GND

values.

Microstructural investigations of materials after severe plastic deformation by means of orientations mapping in TEM and SEM M. Bieda1, A. Jarzębska1, P.Koprowski1,2, J.Kawałko1, K. Kudłacz1, S. Boczkal2, M. Faryna1, K. Sztwiertnia1

1Instititute of Metallurgy and Materials Science Polish Academy of Sciences, Krakow, Poland. 2Institute of Non-Ferrous Metals, Light Metals Division, Skawina, Poland.

Qualitative and quantitative microstructure description of crystalline

materials are crucial for characterization and better understanding of

the mechanisms of deformation and recrystallization processes. In

presented study advanced scanning and transmission electron

microscope methods like t-EBSD, in -situ annealing and orientation

mapping in TEM [1,2] were tested to investigations of materials after

plastic deformations by means of KoBo (extrusion with rotating die)

[3] and hydrostatic extrusion (HE) methods. Statistical analysis of local

orientation, texture and grain boundary characterization were done

for chosen materials of different symmetry like cubic aluminum and

hexagonal zinc and titanium with high resolution capability down to a

few square nanometers. It was proved that those methods can be

successfully applied for complementary analysis to conventional

SEM/EBSD method.

[1] M. Bieda (2012) Sol. St. Phen. 186, 53 [2] www.crystorient.com [3] A. Korbel, W. Bochniak, US Patent No 737, 959 (1998),

European Patent No 0711210 (2000)

EBSD analysis of IF steels: comparison between 2D and 3D statistics S. Ghodrat1, M. Azimi2, 3, E. Lopez2, H. Pirgazi2 and L.A.I. Kestens1, 2 1 Delft University of Technology, Materials Science and Engineering Department, Mekelweg 2, 2628CD Delft, The Netherlands. 2 Ghent University, Department of Materials Science and Engineering, Technologiepark 903, 9052 Zwijnaarde-Gent, Belgium. 3 Isfahan University of Technology, Isfahan, Iran.

Most of the microstructural features in 2D can be characterized

using standard microscopy instrumentation and stereological

procedures; though, there are still many important microstructural

features such as grain boundary inclination or spatial anisotropy of

grain shape, that can only be measured in 3D. Statistical

ABSTRACTS TUESDAY PM1 - CHARACTERIZATION 58

stereological techniques have been developed to gain insight in the

three-dimensional aspects of the microstructure from the 2D data.

To this purpose a commercially cold rolled and annealed IF steel was

examined. By carrying out wide-field 2D and 3D EBSD

characterization, covering an area of 0.42 mm2 and 0.0336 mm3,

respectively, a reference data set was gathered, which provides an

ideal basis for carrying out a statistical analysis This work is of

relevance for constructing virtual representative volume elements

(RVEs) to be employed in microstructurally based FE simulations of

forming operations. The potential will be investigated whether

reliable 3D RVEs can be constructed from 2D conventional EBSD

scans.

ABSTRACTS TUESDAY PM2 - DEFORMATION 59

Symposium D: Deformation Textures Session: Steels - Formability

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Effect of Texture on Mechanically Induced Martensitic Transformation in Duplex Stainless Steel J.-Y. Kang1, H. Kim1, K.-I. Kim2, C.-H. Lee1, H.N. Han2, K.-H. Oh2 and T.-H. Lee1 1Korea Institute of Materials Science, Changwon, Republic of Korea. 2Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul, Republic of Korea.

The effect of austenitic texture on the tensile behavior of a lean

duplex stainless steel was investigated. The texture and grain size

were varied by different history of thermomechanical process while

the phase fraction could be effectively fixed. The shape of tensile

flow curve was primarily affected by austenitic texture while average

grain diameter contributed to the increase in flow stress. The effect

of austenitic texture was attributed to its influence on the

mechanically induced martensitic transformation. In this study,

nearly random austenitic texture exhibited delayed transformation,

consequently resulted in prolonged strain hardening and elongation

than a moderate texture centered at D: {4 4 11}<11 11 8>

component. Dependence of mechanical driving force to

transformation on the austenitic orientation and texture was

analyzed using a simple transformation and crystal plasticity model.

Although D component was supposed to have the smallest

transformation interaction strain along the tensile direction, it

showed the largest stress evolution along that direction. It was

considered that the latter effect overrode the former and resulted in

the observed dependency of the martensitic transformation on the

austenitic texture.

Role of microstructure, texture, and load partitioning in formability of TRIP steel and duplex stainless steel Peijun Hou1, Yuan Li1, Dongchul Chae2, Yang Ren3, Ke An4, and Hahn Choo1

1Materials Science and Engineering, University of Tennessee, Knoxville, TN, 37996, USA. 2Stainless Steel Research Group, POSCO Technical Research Laboratory, Korea. 3X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA. 4Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA

In recent formability studies, a metastable transformation-induced

plasticity (TRIP) stainless steel (SS) exhibited poor resistance to the

delayed cracking phenomenon in deep-drawn cups despite its higher

work hardening rate and ductility compared to a stable austenitic

stainless steel counterpart. In an effort to mitigate this cracking

problem, while keeping the alloy cost down (e.g., lower Ni content),

a duplex SS alloy was developed that indeed demonstrates much

improved resistance to the cracking behavior. However, the duplex

SS shows earing phenomenon instead of cracking in the deep drawn

cups that also needs to be addressed.

The main objective of this present work is to study the constitutive

behavior of the three alloy plates, namely, stable austenite,

metastable austenite (TRIP), and metastable duplex SS alloys. The

goal is to gain basic understanding on the complex relationships

among (1) the alloy composition, (2) constituent phases and their

morphology, (3) macroscopic tensile behavior and anisotropy in

terms of Lankford coefficient, and (4) mesoscopic tensile behavior in

terms of load partitioning, martensitic transformation kinetics, and

texture evolutions.

First, macroscopic tensile behaviors were examined along three

different orientations with respect to the rolling direction of the

alloy plates at ambient temperature to study plastic anisotropy

including the Lankford coefficients. Second, texture and phase

evolutions as a function of applied strain were measured using

synchrotron x-ray diffraction and the results are correlated to the

Lankford coefficient to study the effect of texture and phase

distribution on planar anisotropy. Moreover, the lattice and phase

strain evolutions during uniaxial loading were measured in situ using

neutron diffraction to investigate the effect of strain-induced

martensitic phase (in TRIP SS) and ferritic phase (in duplex SS) on

loading partitioning in comparison to the stable austenitic SS.

This study will provide basic understanding of the alloy behavior for

our concurrent investigation on delayed cracking and earing

phenomena in deep-drawn SS cups.

DAMASK: the Düsseldorf Advanced MAterial Simulation Kit for studying interlinked texture and crystal plasticity phenomena in high strength steels F. Roters, M. Diehl, S.L. Wong, P. Shantraj, D. Raabe Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany.

Here we present DAMASK as a unified freeware texture and crystal

plasticity simulation package. The solution of continuum mechanical

boundary value problems requires a constitutive response that

connects deformation and stress at each material point. In DAMASK

such connection is treated as a hierarchy of three separate items: At

the top-most level, partitioning of the mean boundary values of the

material point among its microstructural constituents and the

associated homogenization of their response is mapped in cases

where there is more than one constituent phase present in the

material. Second, based on an elastoplastic decomposition of finite

strain deformation, these responses follow from time integration of

the plastic deformation rate per constituent. Third, to establish the

latter, a state variable-based constitutive law needs to be

interrogated and its state updated. The Düsseldorf Advanced

MAterial Simulation Kit (DAMASK) reflects this hierarchy as it is

designed in a strictly modular way. This modular structure makes it

straightforward to add additional constitutive models, diffusional

ABSTRACTS TUESDAY PM2 - DEFORMATION 60

and transformation laws as well as homogenization schemes.

Moreover, it interfaces with a number of FE solvers as well as a

spectral solver using an FFT. We demonstrate the features of

DAMASK and apply it exemplarily to several microstructure and

texture related case studies pertaining to the fields of TRIP, TWIP

and dual phase steels.

ABSTRACTS TUESDAY PM2 – RUDY WENK 61

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

Authigenic Mineral Textures in Basaltic Tuff, Surtsey Volcano, Iceland M.D. Jackson1, S. Couper1, N. Tamura2, C.V. Stan2, and L.M. Miyagi1 1University of Utah, Salt Lake City, USA. 2Lawrence Berkeley National Laboratory, Advanced Light Source, Berkeley, USA.

Hydrothermal alteration of basaltic tephra at Surtsey volcano,

erupted during 1963–1967 in the offshore segment of the

southeastern Icelandic rift zone, produces authigenic mineral

textures with preferred orientations in basaltic glass lapilli and

olivine crystal fragments. The microstructures occur in palagonitized

tuff from surficial outcrops and core extracted from a 181 m hole

drilled in 19791. Synchrotron-based microdiffraction and

microfluorescence maps acquired at LBNL Advanced Light Source

beamline 12.3.2 illustrate how dynamic chemical environments in

these microstructures influence rates of reaction as a function of

temperature, glass or crystal composition, exposed surface area of

the solids, and the volume and changing composition of the leaching

solution. The experiments use a monochromatic X-ray beam of 8–10

KeV focused to a 2 by 5 µm2 spot size on a 0.3 mm thick tuff slice

loaded in transmission into the beam, with the detector inclined at

30°–39°. A Pilatus 1M area detector placed at 150 mm records

Debye rings diffracted by crystalline phases. The resulting diffraction

patterns reveal multiple crystallization episodes of zeolite and Al-

tobermorite, a rare, layered calcium-silicate-hydrate mineral with 11

Å interlayer spacing, in association with diverse authigenic clay

mineral textures. In a palagonitized basaltic lapillus at 137.9 m

depth, 85°C in 1980, for example, a transect across leached glass

into an internal vesicle shows early phillipsite associated with

nanocrystalline clay mineral with 14.2–14.8 Å interlayer spacing;

acicular 11.35 Å Al-tobermorite ([Ca4(Si5.5Al0.5 O17H2)]

Ca0.2·Na0.1·4H2O) that precipitated from highly alkaline leachate

fluids with [002] interlayer spacing oriented radially to vesicle walls;

and subsequent analcite replacing Al-tobermorite. Nanocrystalline

clay mineral in the altered glass has d-spacings similar to nontronite,

either with random c-axis (001) orientations or with preferred

orientations that rotate from 0°–180° over 25–50 µm transects.

These define tubular microchannels produced, perhaps, by early

biogenic activity. In the rim of an altered olivine crystal at 102.6 m

depth, 141°C in 1980, for example, the clay mineral structure wraps

around the tubules in successive 5–10 nm thick layers, shown by

microdiffraction and S/TEM analyses; the (001) d-spacing decreases

from 14.5 Å to 14.2 Å in the external layers. Al-tobermorite with

11.33 Å interlayer spacing occurs at the periphery of these

microstructures. Fifteen years after eruption, the authigenic Al-

tobermorite–zeolite–nanocrystalline clay mineral textures record

abiotic processes produced by reactive rock–water interactions as

well as potentially biogenic processes, perhaps associated with early

infiltration of seawater into the tephra deposits.

[1] S.K. Jakobsson and J.G. Moore (1986) Geological Society America Bulletin, 97, 648–659.

Study by XRD and EBSD of texture and microstructure of the eggs of Chelonoidis chilensis turtle V. Tartalini1, P. Risso1, R.E. Bolmaro1 and M.C. Avalos1 1Instituto de Física Rosario, CONICET-UNR, Rosario, Argentina.

Calcite and aragonite are the two most important and abundant

crystalline forms of CaCO3. Calcite is one of the most abundant

minerals in the earth crust. Aragonite, despite being unstable at

surface conditions of pressure and temperature, is also present in

large mineral deposits. They are almost evenly distributed as

mollusk shell bio mineral constituents, either as sole component or

combined with each other. In eggs, of avian or reptilian origin,

calcite is absolutely dominant. Only some species of land turtles are

known being composed of aragonite. This clear distinction attracted

attention and drove us to characterize turtle eggs in search for

microstructural characteristics and correlation with other species´

eggs.

The studies were performed by scanning turtle eggs of Chelonoidis

chilensis on the Radial-Tangential planes all through the almost 1

mm thickness. Also, X ray pole figures were measure by the

reflection Schultz method.

The structure resulted in a four layered calcite-aragonite composite

material, which probably highly enhance mechanical properties.

Resultant textures are correlated with avian and reptilian egg

results, form the literature and other species characterized by the

same techniques.

Multigrain crystallography as a tool for texture analysis under high pressures and temperatures Joel Vincent Bernier Lawrence Livermore National Laboratory, Livermore, CA 94550, USA

Multigrain crystallography is a recently establish extension of the

traditional single-crystal rotation method that facilitates the

simultaneous analysis of up to 𝒪(1000) crystallites in a single

diffraction volume. The technique was originally developed within

the materials science community as a means for isolating individual

grain responses within bulk polycrystalline samples that were

subject to deformation in situ. More recently, the technique has

been applied to a much broader array of material science problems,

including high-pressure/temperature studies. The multigrain

technique is particularly useful in the context of geophysical

research. Examples include the study of phase transitions and

plasticity, as well as other cases where adequate powder patterns

are difficult to obtain, such as for experiments performed at high

temperatures where grain growth is a complicating factor. While the

measurements required are quite straightforward, the analysis in

not; indeed the scarcity of robust and user-friendly software to solve

ABSTRACTS TUESDAY PM2 – RUDY WENK 62

the deconvolution problem is a major barrier to the more

widespread application of multigrain crystallography in the high

pressure/temperature field. In this talk, the workflow of multigrain

crystallography is presented in the context of the open-source

HEXRD software package. Current capabilities, limitations, and

future extensions are presented alongside several examples. These

include the high-pressure α↔ε phase transition in iron and the

α→ω phase transition in zirconium. The resolution of the method is

shown to isolate the specific transformation mechanisms and

demonstrate the influence of the stress deviator on the variant

selection. Because fully three-dimensional data are available, no

recourse to kinematic modeling or assumptions regarding the

applied stress are required to determine the lattice parameters. In

summary, the technique shows great promise with respect to

ongoing studies of deformation mechanics under high pressure.

This work was performed under the auspices of the U.S. Department

of Energy by Lawrence Livermore National Laboratory under

Contract DE-AC52-07NA27344. Funding through the Laboratory

Directed Research and Development program (10-ERD-053 & 13-

ERD-078) is gratefully acknowledged.

ABSTRACTS TUESDAY PM2 - RECRYSTALLIZATION 63

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

Relationship between Zener-Holloman Parameter, Grain Size Refinement, and Texture Evolution during Dynamic Recrystallization of AZ31B Mg Alloy Yuan Li1, Zhenggang Wu2, Peijun Hou1, Zhili Feng2, and Hahn Choo1 1Materials Science and Engineering, University of Tennessee, Knoxville, TN, 37996, USA. 2Materials Science & Engineering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6095

The dynamic recrystallization behavior of a wrought magnesium

alloy plate (AZ31B) with basal texture was studied using the Zener-

Holloman (Z-H) parameter as quantitative criteria for the changes in

deformation and recrystallization mechanisms. A series of

compression tests were conducted for the AZ31B plate samples

along the transverse direction (TD) using a Gleeble system at various

temperature and strain rates covering about eight orders of

magnitude of Z-H parameter. In this paper, we will present the

dynamic recrystallization behavior observed in three Z-H parameter

regimes: namely, low Z, mid Z, and high Z, through which the grain

size refinement changes from homogeneous to bimodal and the

texture changes from the initial basal to off-normal texture.

Moreover, the role of twinning in the grain refinement and texture

formation during recrystallization will also be discussed. The current

study provides a basic understanding of the microstructure

development during the hot working of magnesium alloys including

the friction stir welding.

Incorporating Texture Models in Monte Carlo Simulations of Solidification Theron M. Rodgers1, Efrain Hernandez-Rivera2, Judith A. Brown1, Kyle L. Johnson1, Jonathan D. Madison1, Fadi Abdeljawad1

1Sandia National Laboratories, Albuquerque, USA. 2Army Research Laboratory, Aberdeen Proving Ground, USA.

Recently, a novel simulation technique has been developed to

simulate the formation of grain microstructures in rapid

solidification events found in welding and additive manufacturing.

However, material properties in the initial model implementations

were isotropic. Here we introduce a grain-orientation dependent

model for the incorporation of the anisotropy in cubic materials. The

model allows for the prediction of crystallographic texture during

solidification events. It also accounts for changes in solid state grain

evolution due to misorientations between neighboring grains.

Simulation results will be presented for additive manufacturing and

laser welding simulations.

Sandia National Laboratories is a multi-mission laboratory managed

and operated by Sandia Corporation, a wholly owned subsidiary of

Lockheed Martin Corporation, for the U.S. Department of Energy’s

National Nuclear Security Administration under contract DE-AC04-

94AL85000.

the mechanical property of zirconia coatings and ceramics.

ABSTRACTS TUESDAY PM2 - CHARACTERIZATION 64

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National Laboratory

Advances in 3D Grain Mapping with LabDCT Florian Bachmann1, Allan Lyckegaard1, Hrishikesh Bale2, Christian Holzner2, Leah Lavery2 and Erik Lauridsen1 1Xnovo Technology ApS, Køge, Denmark. 2Carl Zeiss X-ray Microscopy, Inc. Pleasanton, CA, USA.

Laboratory diffraction contrast tomography (LabDCT) with a ZEISS

Xradia Versa X-ray microscope opens up new possibilities of non-

destructive 3D and time resolved 4D studies of polycrystalline

material using a laboratory X-ray source. In addition to absorption

contrast and phase contrast tomography, the LabDCT imaging

modality spatially resolves crystallographic orientation of individual

grains. The unique LabDCT approach exclusively closes the gap to

synchrotron 3D grain mapping techniques within laboratory

research. Though, laboratory X-ray sources notoriously suffer from

order of magnitude lower brilliance compared to synchrotron

sources, grain mapping in the laboratory becomes possible by

exploiting the Laue focusing effect. Grain shapes and boundaries of

metals, alloys or ceramics can be characterized fully in 3D. In

particular, crystalline microstructures with negligible or no

absorption or phase contrast can now be studied. This novel non-

destructive laboratory technique enables the observation and

characterization of microstructural response to stimuli (stress,

thermal, radiation) of one and the same sample over time.

Morphological and orientation development of individual grains and

their grain boundaries can be accessed and tracked. Examples in

both 3D and 4D will demonstrate current capabilities of the LabDCT

technique for texture and microstructure characterization.

In-grain orientation spreads in deformed aluminium: 3DXRD-based measurements and finite element simulations L. Renversade and R. Quey

MINES Saint-Etienne, CNRS UMR 5307, Saint-Etienne, France.

The crystal orientations and rotations of about 500 grains of an

aluminium polycrystal deformed in tension were analysed in-situ

using high-energy X-ray diffraction techniques. While the initial

microstructure was mapped by diffraction contrast tomography

(DCT), the lattice rotations of the grains were then followed by 3D X-

ray diffraction microscopy (3DXRD), at strains of 1.0, 1.5, 2.0, 2.5 and

4.5%. First, the average grain orientations were determined from

the positions of the diffraction peaks through standard indexing

techniques. Second, a new method was developed to extract

information on the in-grain orientation distributions from the

spreading of the diffraction peaks. The method assumes a simplified

shape of the orientation distributions and optimizes its parameters

to get the best possible match between the experimental diffraction

patterns and the diffraction patterns simulated from the orientation

distributions using a virtual diffractometer. The preferential

disorientation axes of the orientation distributions were then

analysed in terms of distribution over all grains and correlation to

the grain average orientations. It is shown that the axes

preferentially develop about the tensile direction at strain lower

than 2% and then migrate to a direction normal to the tensile

direction. The results were compared to those obtained by a high-

resolution finite element simulation of the polycrystal deformation.

It is shown that the finite element model properly reproduces the

distributions at largest strains.

Using High Energy Diffraction Microscopy (HEDM) to validate micromechanical fields calculated by FFT based method Vahid Tari1, Ricardo A. Lebensohn2, Reeju Pokharel2, Anthony D. Rollett1 1Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA15213, USA. 2Los Alamos National Laboratory, Los Alamos, NM 87545, USA

High Energy Diffraction Microscopy (HEDM) is both an in-situ and

non-destructive technique. HEDM was used to measure

micromechanical fields such as strain and orientation at the grain

scale developed under macroscopic tensile loading of Ti-7Al. Taking

the 3D image of the experimentally measured initial microstructure

as input, elasto-viscoplastic modeling based on the Micromechanical

Analysis of Stress-Strain Inhomogeneities with Fourier transforms

(MASSIF) was used to compute the micromechanical fields that

develop during loading. To validate the MASSIF calculations, we

compared the calculated fields with the ones measured by HEDM.

The initial comparisons showed that MASSIF can reproduce the

average stress/strain values but poor agreement was found

between calculated and measured fields at the grain scale. The

differences at the grain scale were hypothesized to be caused by the

initial residual stress state that was induced during prior material

processing, and which was not incorporated in the MASSIF

calculation. We used eigenstrain concept to incorporate residual

stress in the MASSIF calculation by converting it to an initial

eigenstrain field. The results reveal that incorporation of residual

stress results in good agreement between calculated and measured

fields at the grain scale, thereby validating the computational

approach.

ABSTRACTS WEDNESDAY - GENERAL 65

WEDNESDAY GENERAL SESSION

Video Presentation: Peter Bunge

Bunge Award Presentation

Bunge Awardee Presentation

ABSTRACTS WEDNESDAY AM - DEFORMATION 66

Symposium D: Deformation Textures Session: Aluminum

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Evolution of deformation texture during flat profile extrusions and its understanding by FEM and crystal plasticity modelling K. Zhang1, A. Segatori2, T. Aukrust3, B. Holmedal4,and K. Marthinsen5 1,4,5Norwegian University of Science and Technology, Trondheim, Norway. 2SAPA Technology, Finspång, Sweden. 3 SINTEF Materials and Chemistry, Oslo, Norway.

The evolution of deformation texture during the flat profile extrusion

process is experimentally and numerically investigated. Extrusion

trials were performed at a relatively low temperature to produce

small flat profiles from a round billet of the aluminium alloy 6063

material. The butt-end (material left in the container) and the profile

were simultaneously water-quenched at the end of extrusion. By the

electron back-scatter diffraction technique (EBSD), the deformation

microstructure and texture were measured in the centre regions both

of the butt-end and of the profile. The profile is of a conventional β-

fibre texture plus some Cube texture, whereas a strong <111> and

weak <100> duplex fibre texture is observed in the butt-end where

close to the inlet of die pocket. Deformation histories for the centre

regions were extracted from the material flow simulation using a

commercial FEM code. Analysing the deformation histories reveals

that it is close to uniaxial tension deformation in the billet until a short

distance to the inlet of pocket, while the material experiences

approximate plane strain deformations when traveling into and

through the pocket of the die. The deformation textures after plane

strain deformation was simulated using the FC-Taylor model, starting

with only <111> and <100> fibre orientations, respectively. The

simulation shows that the <111> fibre will rotate into the beta-fibre

under plane strain deformation. By simulation, the <100> fibre will

concentrate on the Goss orientation with some Cube left. The texture

evolution during this flat profile extrusion can then be well

understood.

Rolling Texture Development in Aluminum-Zinc Solid Solutions B. Merkley, B.J. Diak, and O. Gopkalo Queen’s University, Kingston, Ontario, Canada

Aluminum (Al) has a relatively high stacking fault energy compared

to other face-centered-cubic crystalline elements, and so its

deformation is often characterized by greater potential for cross-slip

and recovery at higher temperatures and organization of a more

cellular work-hardened dislocation structure. It has been observed

that the rolling textures in face-centered cubic polycrystalline metals

tend to transform from so-called pure metal to alloy textures with

increasing stacking fault energy, so deformation texture correlates

directly to stacking fault energy. As a 30th anniversary tribute to the

classic Cu-xZn study by Hirsch and Lücke [1], we recast the problem

for binary Al alloys with 1, 10, and 30wt.%Zn. Zinc (Zn) has a very

high solid solubility in Al of up to 65at.% at 381°C, but at lower

temperatures the Zn solid solution is highly unstable and can

precipitate out or decompose spinodally. Current understanding is

that Zn has no effect on the stacking fault energy of aluminum, so a

priori, rolling of different Al-xZn alloys should result in no variation in

deformation texture. Ingots were cast from book moulds,

homogenized at 428°C for 96 hours and water cooled, cut from the

ingot for rolling, reheated to 428°C for 10 minutes, water quenched

to ice water, warmed to room temperature and promptly rolled 75

and 90% by multiple passes. X-ray texture pole figures were

measured at the mid-plane of the rolled sheet, and the texture

components calculated from the crystallographic orientation

distribution function. Results show a decrease in {112}<11-1> with

Zn content but uncorrelated changes in {011}<21-1> and {123}<63-

4> components. A quantitative understanding of the effect of the

solid solution on the rolling texture development will be presented

in the context of the crystallographic orientation distribution.

[1] J. Hirsch and K. Lücke (1988) Acta metall. 36, 2863. Originally submitted September 28, 1987.

Investigation of inhomogeneous deformation and microstructure during cold rolling in Al-Mg alloys by using 3D marker tracking method M. Kobayashi, M. Nakayama, T. Aoba and H. Miura Toyohashi University of Technology, Toyohashi, Japan.

To understand local inhomogeneous deformation during thermo-

mechanical processing is very important for understanding and

prediction of texture evolution, because localized deformation

would affect not only formation of deformation texture but also

development of recrystallized texture. In this study, development of

inhomogeneous plastic strain in 3D had been measured in cold

rolled Al-Mg alloys that contain small lead particles, which are

marker of local strain measurement, by using synchrotron radiation

micro-tomography. The strain distributions in different Mg content

and rolling ratio were compared with microstructures obtained by

SEM/EBSD. The relationship between local deformation and grain

microstructure is discussed.

New insights on modeling deformation texture and yield strength anisotropy in age hardenable Al-Mg-Si alloys Sumeet Mishra, Manasij Yadav, Kaustubh Kulkarni, N.P.Gurao Indian Institute of Technology, Kanpur, Kalyanpur, India

In the present investigation, effect of coherent directional

precipitates on rolling texture evolution and the resultant yield

strength anisotropy was thoroughly investigated. It was found that

depending upon temper condition a transition in texture from

copper type to brass type can be observed. A copper type texture

ABSTRACTS WEDNESDAY AM - DEFORMATION 67

was observed in the solutionized sample, whereas brass type texture

was found in the peak aged sample. Texture evolution during

different stages of rolling reduction was analyzed quantitatively in

terms of positions of orientation tubes and volume fraction of ideal

texture components. Texture simulations were carried out in the

framework of classical full and relaxed constraint Taylor model to

the more advanced visco -plastic self consistent model and grain

interaction model like LAMEL. It was found that the in the presence

of solute elements, Taylor model gave good agreement with

experimentally determined texture and the yield strength

anisotropy. However, in the presence of coherent precipitates all

the existing models fail to provide satisfactory agreement with

experimental results. A modified Taylor model proposed in the

present work yields much better results than the existing models in

predicting texture evolution and yield strength anisotropy of peak

aged sample. Modified Taylor model considers additional work done

in deforming the precipitates in addition to work done in deforming

the matrix, thereby maintaining compatibility at precipitate-matrix

interface. Due to needle shaped morphology of the precipitates,

some of the shear strain components were relaxed during texture

simulations. Applicability of the model is further showcased by

extending the model to other age hardenable alloys with different

morphology and habit plane of precipitates.

Impact of Texture on Anisotropy and Delamination Cracking in Al-Li Alloys Wesley Tayon1,3, Roy Crooks2, and Ashley Spear3 1NASA Langley Research Center, Hampton VA 23681. 2Black Laboratories, L.L.C., Newport News, VA 23601. 3University of Utah, Salt Lake City, UT 84112

Aluminum-lithium (Al-Li) alloys offer significant performance

benefits over conventional aluminum alloys for aerospace structural

applications. However, their widespread use has been limited due to

highly anisotropic material properties and concerns regarding

delamination fracture. The beta-fiber texture components (namely

the Brass texture component) heavily contribute to anisotropy in

these alloys along with delamination cracking. Delamination is a

secondary form of fracture along flat grain boundaries that occurs as

a result of highly localized deformation. Grain pairs, such as Brass

variants, that develop strong indications of local heterogeneity in

mechanical behavior are more likely to delaminate. State-of-the-art

experimental and computational methods are used to explore the

role of texture in these alloys with respect to anisotropy and

delamination. Results will address localized deformation as a result

of planar slip due to slip system softening within grains and slip

incompatibility at grain boundaries. Ultimately this will provide

designers the information needed to develop appropriate design

standards for these alloys and enable increased deployment in the

aerospace community.

ABSTRACTS WEDNESDAY AM – RUDY WENK 68

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

A trip with Rudy: from calcite to quartz C.N. Tomé1, R.H. Wenk2

1MST Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. 2 Department of Earth and Planetary Science, University of California, Berkeley, CA, USA

I started my research trip with Rudy Wenk in 1987, in what was my

first exposure to plasticity of geological materials. Specifically, trying

to understand in terms of slip activity the measured crystallographic

textures of calcite when deforming by shear at different

temperatures. This trip took us through several geological and

metallic systems, with deformation texture being the guiding

evidence and crystal plasticity the compass for trying to infer

information about crystallographic slip and twinning.

Today, 30 years later, still finds us on the same quest but with much

more powerful tools available. Our experimental characterization

techniques and our material deformation models have advanced

enormously in these three decades.

This presentation will summarize the relevant instances of such trip

and will discuss our most recent collaboration on trying to explain

the piezo-crescence mechanism in quartz. Piezo-crescence refers to

the finding that Dauphine twins in quartz can be created or reversed

(detwinned) with the application of a stress field. However, the large

elastic and plastic anisotropy of quartz crystals makes it difficult to

infer the actual stress state in grains from the knowledge of the

applied stress. Our modeling of this process will account for elasto-

plastic anisotropy within the framework of an elasto-visco-plastic

polycrystal model. Predictions of grain reorientation will be

compared to the large available experimental evidence of piezo-

crescence. And we expect to confirm that such the Dauphine twin

transformation is driven by the local stress field in individual grains

via elastic energy minimization.

20 years inspired by Rudy Wenk’s challenges to model texture, microstructure and anisotropy of geomaterials R.A. Lebensohn Los Alamos National Laboratory, Los Alamos, NM, USA

In 1997 I spent 3 months in UC Berkeley working with Rudy Wenk.

Since then, Rudy’s numerous challenges to model and interpret

observations involving texture, microstructure and anisotropy of

materials of the Earth’s interior—obtained by means of

experimental techniques that, in many instances, Rudy himself

pioneered—have been an inspiration for improving our models to

tackle fascinating problems involving low-symmetry crystalline

materials. In this talk I will summarize some our attempts over the

years to explain Rudy’s observations, using two kinds of polycrystal

plasticity formulations, the mean-field viscoplastic self-consistent

model and the full-field FFT-based formulation.

Texture formation in ionic crystals with rock salt structure W. Skrotzki Institute of Structural Physics, Technische Universität Dresden, 01062 Dresden, Germany

Ionic crystals with the rock salt structure (B1) are plastically very

anisotropic and therefore have often been considered as model

materials for rocks. As texture represents a fingerprint of the

thermo-mechanical history of rocks, based on many years of

research on ionic crystals with different ionicity a review is given on

texture formation in this material class as a function of mode and

temperature of deformation. The results will be discussed with

regard to deformation mechanisms (slip system activity), but also

recrystallization and grain growth. Moreover, polycrystal plasticity

simulations will be applied and compared to experiment.

A Method for Including Diffusive Effects in Texture Evolution N.R. Barton1, E. Zepeda-Alarcon2, R.A. Lebensohn3, and M.C. Messner4 1Lawrence Livermore National Laboratory, Livermore CA, USA. 2University of California, Berkeley CA, USA. 3Los Alamos National Laboratory, Los Alamos NM, USA. 4Argonne National Laboratory, Lemont IL, USA.

One of the longstanding challenges associated with homogenization-

based models for the prediction of texture evolution is that they

tend to predict textures that are too sharp. In some cases, the

predicted components are absent in experimental observations.

Here we present a new approach to address at least some aspects of

this issue. We make use of recently developed capabilities for

computation of intragranular fluctuations. These computations,

conducted in a viscoplastic self-consistent (VPSC) framework,

provide a tensorial measure of the trend for misorientation

development inside each single crystal grain representing a

polycrystalline aggregate. These results are then used to drive a

diffusive term in the texture evolution. The method employs finite

elements over Rodrigues space as a convenient means of computing

the operators involved in the evolution of the texture, including the

diffusive operator. Degrees of freedom in the texture evolution are

then associated with a discrete harmonic expansion. In this way, the

finite element resolution controls the accuracy of the integrals for

the operators, and the degree of the discrete harmonic expansion

controls the fidelity of the texture representation. Overall this forms

an attractive and flexible framework. In previous work, this

framework was used with non-local operators to capture twinning,

and here it is extended to include the diffusive contribution from

intragranular fluctuations. Example results will be shown the texture

evolution with and without the diffusive contribution. This work was

performed under the auspices of the U.S. Department of Energy by

ABSTRACTS WEDNESDAY AM – RUDY WENK 69

Lawrence Livermore National Laboratory under Contract DE-AC52-

07NA27344 (LLNL-ABS-719278).

Fabric Transitions in Quartz via Visco-Plastic Self-Consistent Modelling: Axial Compression and Simple Shear under evolving Strain L. F. G. Morales1, D. Mainprice2 and K. Kunze2 1ETH Zurich, ScopeM, Zurich, Switzerland. 2 Geosciences Montpellier, Montpellier, France.

Quartz is a common crustal mineral that deforms plastically in a

wide range of temperatures and pressures, leading to the

development of different types of crystallographic preferred

orientation (CPO) patterns. In this contribution we present the

results of an extensive modelling of quartz fabric transitions via

visco-plastic self- consistent (VPSC) approach. For that, we have

performed systematic simulations using different sets of relative

critical resolved shear stress of the main quartz slip systems. We

have performed these simulations in axial compression and simple

shear regimes variable strains up to a maximum of Von Mises

equivalent strain of ~ 350% (γ=6). In these models we assume that

the aggregates deformed exclusively by dislocation glide. Some of

the predicted CPOs patterns are similar to those observed in

naturally and experimentally deformed quartz, and some patterns

are developed in a wide condition variation. Nevertheless, some

classical CPO patterns usually interpreted as resulting from

dislocation glide (e.g. Y-maxima due to prism <a> slip) are developed

just under very specific conditions. In addition, we report potentially

new preferred orientation patterns that might develop in high

temperature conditions, both in axial compression and simple shear.

We have demonstrated that CPOs generated under axial

compression are usually stronger that those predicted under simple

shear, due to the continuous rotation observed in the later

simulations. The fabric strength depends essentially on the

dominant active slip system, and normally the stronger CPOs result

from dominant basal slip in <a>, followed by rhomb <a> and prism

[c] slip, whereas prism <a> slip does not produce strong fabrics,

unless in very high strains.

The Androgynous Twins of Zinc S. Merkel1, N. Hilairet1, C. Tomé2

1Université de Lille, 59000 Lille, France. 2Los Alamos National Laboratory, Los Alamos, NM 87545, USA

Zn is a hexagonal metal with a large c/a ratio under ambient

conditions (c/a=1.856). Under ambient testing conditions,

deformation is predominantly accommodated by basal <a> slip and

by {10-12} <11-23> compression twinning. Remarkably, increasing

hydrostatic pressure drastically reduces the c/a ratio of Zn, a

phenomenon known as anomalous pressure dependence. As a

consequence of the unit cell dimensional change, the compression

twin is predicted to become a tensile twin when c/a<√3 at P>9 GPa.

In this work we strain-cycle a wire of pure Zn in the D-DIA

deformation press under multiple superimposed hydrostatic

pressures ranging between 3 and 17 GPa. Over this pressure range,

the c/a ratio of Zn will go over the compressive-tensile transition.

During deformation, the state of the sample is monitored in-situ

through powder x-ray diffraction, allowing the extraction of texture

and sample stress. Elasto-visco-plastic polycrystal simulations of the

cyclic process allow us to interpret the experimental data and to

elucidate the type and strength of the crystallographic deformation

mechanisms.

The purpose of this work is to elucidate the active deformation

modes as a function of pressure. Specifically: 1) to determine if

detwinning is a possible mechanism at 3 GPa pressure when Zn is

cycled in tension-compression; 2) to find out if at a pressure state

where c/a~√3 only basal slip is active or whether another slip

mechanism operates, and which; 3) to find out whether {10-12}<11-

23> tensile twins are active in Zn when c/a<√3.

ABSTRACTS WEDNESDAY AM - TRANSFORMATIONS 70

Symposium T: Transformation Textures Symposium Chair:

Dr. Michael Roach, Biomedical Materials Science, University of Mississippi Medical Center

Variant selection mechanisms and quantitative prediction of transformation textures in steel T. Tomida1, Y. Onuki2 and S. Sato2,3

1Ibaraki Prefectural Government, Tokai, Japan, 2Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Japan, 3Graduate School of Science and Engineering, Ibaraki University, Hitachi, Japan

Variant selection mechanisms in the phase transformation in steel

have been investigated to quantitatively predict transformation

textures. Two variant selection mechanisms have been recently

introduced by the author and his coworkers [1,2]. The one is that

the variant having Kurdjumov-Sachs (K-S) orientation relation or the

one near the K-S with two adjacent parent grains is preferentially

selected, which we call the double K-S relation (DKS) [1]. More

recently the other mechanism based on the elastic anisotropy in

neighboring matrices has been introduced for martensite

transformation [2]. The elastic energy required for the

accommodation of the shape strain due to displacive transformation

does not depend on variants when the medium to accommodate it

is immediate parent grains, in which martensite grows, since all the

variants are crystallographically equivalent to the immediate parent

grain. However, if the medium is neighboring non-immediate parent

grains (without orientation relationship) or preexisting martensite,

the elastic energy can be dependent on variants due to the elastic

anisotropy of the medium. Thus, in this mechanism, the variant with

a lower elastic energy in adjacent parent grains and preexisting

martensite is preferentially selected. While the selection mechanism

by DKS is dominant for the diffusive transformation, the latter

mechanism by elastic anisotropy should be dominant for martensite

transformation. With these mechanisms and the spherical-

harmonics-based calculation method for transformation textures,

the textures by diffusive and displace transformations can be

quantitatively well predicted. Such mechanisms and calculation

results based on recent diffraction experiments via a neutron

diffractometer, i-MATERIA, in J-PARC will be presented in the

conference.

[1] T. Tomida, M. Wakita, M. Yoshida, N. Imai (2008) Proc. 15th ICOTOM, 325.

[2] T. Tomida, to be published.

β-Mn transformation and orientation relationship in austenite-based FeMnAlC low-density steel S.-J. Park1, K. Lee2, J.-Y. Kang1, J.Y. Park1, J. Moon1, A.D. Rollett3 and H.N. Han2 1Korea Institute of Materials Science, Changwon, Republic of Korea. 2Seoul National University, Seoul, Republic of Korea. 3Carnegie Mellon University, Pittsburgh, USA

Low-density steels usually contain aluminum which provides density

reduction effect. Among the low-density steels, austenite-based

FeMnAlC steels have shown superior mechanical properties and

weight reduction rate. In the austenite-based FeMnAlC steels, β-Mn

phase can be formed depending on chemical composition and heat

treatment conditions, which is known to be detrimental to ductility.

However, little information about the transformation from austenite

(γ) to β-Mn is available including nucleation, growth behavior and

orientation relationship. In this work, formation of β-Mn phase in

Fe-30Mn-11Al-0.9C alloy during aging at 550oC was investigated. The

microstructure was observed using electron backscatter diffraction

(EBSD) analysis and transmission electron microscopy (TEM). The β-

Mn phase grew extensively into γ grains showing Widmanstätten-

type morphology. Lattice expansion of γ and carbon enrichment in γ

caused by β-Mn formation was examined using X-ray diffractometry

(XRD) and electron probe micro-analyzer (EPMA). The

crystallographic orientation relationship between γ and β-Mn was

analyzed by orientation relationship stereogram (ORS) using EBSD

data. The ORS results were verified by TEM diffraction patterns at

the interface boundaries.

Austenite Reconstruction Elucidates Prior Grain Size Dependence of Toughness in a Low Alloy Steel C. Ranger1, V.H Tari1, A.D Rollett1, M.J. Merwin2, and S. Farjami2 1Carnegie Mellon University, Pittsburgh, USA. 2U.S. Steel Research and Technology Center, Munhall, USA.

Texture and grain size distribution of austenite phase at high

temperature have distinct effects on mechanical properties of steel

alloys at room temperature, but measurement of austenite at high

temperature is not a trivial task and is not always feasible. So,

developing a technique predicting austenite texture and grain size at

high temperature is highly desirable. In this work, we review several

samples of pipe steels with different martensitic microstructures at

room temperature and wide variations in toughness results. These

variations were not explained by the microstructure and

morphology of the room temperature martensite phase. We

developed and applied an algorithm to reconstruct the parent

austenite at high temperature from martensite microstructure at

room temperature. This technique successfully reconstructed prior

austenite grains in samples with different microstructures. Our

results clearly indicate the distribution of austenite grain size in each

sample strongly depends on processing history. Furthermore, the

results revealed that variations in toughness of each sample were

correlated to texture, grain orientation spread, and grain size of

austenite.

Variant Selection at Parent Phase Grain Boundary

Nucleation During -to- Phase Transformation in Low Carbon Steel L. A. I. Kestens1,2, J. Galan Lopez2,3 and Kees Bos4 1Ghent University, Ghent, Belgium. 2Delft University of Technology, Delft, The Netherlands. 3M2i, Materials Innovation Institute, Delft, The Netherlands. 4Tata Steel R&D, IJmuiden, The Netherlands.

In a previous work, it was shown that the occurrence of a double

Kurdjumow-Sachs (KS) orientation relation for a ferrite grain

nucleating at a grain boundary of the parent austenite structure,

strongly favors the nucleation propensity, as the double coherent

ABSTRACTS WEDNESDAY AM - TRANSFORMATIONS 71

interface of the newly formed phase boundary drastically reduces

the phase boundary energy. This condition implies a variant

selection rule, as only one out of the 24 possible variants will comply

with the requirement of a double KS orientation relation. This rule

was included in a crystallographically resolved version of a cellular

automaton model (CA) that was published before and which was

successfully applied to model the kinetics of the -to- phase

transformation for low-carbon steels.

For each parent phase grain boundary, the crystallographic

misorientation was calculated and it was assumed that the driving

force exhibits a Gaussian dependence on the orientation distance

from the double KS orientation relation. This nucleation rule

produced a near random ferrite product texture when the parent

austenite texture was random. In case the parent texture was

dominated by a strong cube component, the product texture was

characterized by a (weak) rotated cube component ({001}<110>). In

absence of variant selection, the product texture displayed three

components: the rotated cube component, the Goss component and

the rotated Goss component ({001}<110>, {110}<001> and

{110}<110>, respectively). The disappearance of the latter two

components in the product texture because of the double KS

nucleation restriction, corresponds remarkably well with

experimental observations of ferrite hot band textures in low-carbon

steels, finish rolled above the non-recrystallization temperature.

Crystallographic Reconstruction of Parent Austenite Twin Boundaries in a Lathe Ferritic Steel Stephen Cluff1, David Fullwood1, Tracy Nelson1 and Rongjie Song2 1Department of Mechanical Engineering, Brigham Young University, Provo UT, USA. 2ArcelorMittal Global R&D—East Chicago Automotive Products, East Chicago, IN, 46312, USA

The study of post-transformation microstructures and their

properties can be greatly enhanced by studying their dependence on

the grain boundary content of parent microstructures. Recent work

has extended the crystallographic reconstruction of parent austenite

in steels to include the reconstruction of special boundaries, such as

annealing twins. These reconstructions present unique challenges,

as twinned austenite grains share a subset of possible daughter

variant orientations. This gives rise to regions of ambiguity in a

reconstruction. A technique for the reconstruction of twin

boundaries is presented here that is capable of reconstructing 60°

<1 1 1> twins, even in the case where twin regions are comprised

entirely of variants that are common between the twin and the

parent. This technique is demonstrated in the reconstruction of an

x80 lathe ferritic steel. The reconstruction approach utilizes a

delayed decision making approach, where a chosen orientation

relationship is used to define all possible groupings of daughter

grains into possible parents. These overlapping, inclusive groupings

(called clusters) are compared to each other individually using their

calculated parent austenite orientations and the topographical

nature of their overlapping regions. These comparisons are used to

uncover possible locations of twin boundaries present in the parent

austenite. This technique can be applied to future studies on the

dependence of post-transformation microstructures on the special

grain boundary content of parent microstructures.

Reconstruction of austenite microstructures in steels by global optimization of misorientation functions T. Nguyen-Minh1,2, E. Gomes2, R.H. Petrov1,2 and L.A.I. Kestens1,2

1Department of Materials Science and Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands. 2Department of Electrical Energy, Metals, Mechanical Construction and Systems, Ghent University, Tech Lane Ghent Science Park – Campus A, Technologiepark 903, B9052 Zwijnaarde, Belgium

During the phase transformation from austenite to martensitic or

bainitic ferrite in steels, crystallographic orientations of product

grains are defined by their parent orientations and the orientation

relationship between parent and product crystals. Therefore,

boundaries between ferrite variants from the same parent austenite

in a microstructure, are distinguished by their special

disorientations, rather than the random misorientation. By analyzing

the misorientation distribution between ferrite product grains, prior

austenite grain boundaries are able to be revealed and the

microstructure of the parent austenite can be reconstructed. In this

study, austenite microstructure reconstruction is carried out by

global optimization of two separate misorientation functions. By

optimization procedures, it is able to determine the average

orientation relationship and consequently the parent orientations

for each EBSD pixel. Application of the reconstruction model is

illustrated by calculations of prior-austenite microstructures in

quenched samples of low carbon steels and Fe-29 wt.% Ni alloy.

ABSTRACTS WEDNESDAY AM - ENGINEERING 72

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Processing – Accumulated Roll Bonding

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Study of the texture developed by ARB and CARB processes on an AA5754/AA6061 composite K. Verstraete, A.-L. Helbert, F. Brissetand T. Baudin ICMMO, SP2M, Université Paris-Sud, Université Paris-Saclay, UMR CNRS 8182,91405 Orsay Cedex, France

Accumulative Roll-Bonding (ARB) [1], as a severe plastic deformation

process, is suitable to refine the microstructure and as a

consequence to enhance mechanical properties (Hall-Petch law).

Besides, change of strain path is known as another way to

strengthen metals. Thus, Cross ARB (CARB) [2], which combines both

ARB and rotation of the Rolling Direction (RD), is a very interesting

process.

The present work aimed to compare ARB and CARB processes in a

textural way, both at room and hot temperature. At room

temperature, elaborated composites show a clear separation.

Indeed, while ARB samples show a typical FCC rolling texture (S,

Dillamore, Brass and Goss), CARB samples develop a texture

embodied by a strong ND (Normal Direction)-rotated Brass with

minor Dillamore and S components. The singular symmetry of the

ND-rotated Brass allows an isotropy of the yield stress in the two

main directions RD and TD (transverse direction) of the sheet plan.

At hot temperature, and whatever the process, the texture is mainly

represented by the rotated Cube component, allowing in addition a

good isotropy of the yield stress. Finally, whatever the temperature,

the yield stress is found higher in CARB than in ARB.

[1] Y. Saito, H. Utsunomiya, N. Tsuji& T. Sakai, (1999) Acta Materialia47 579.

[2] S. Kaneko, K. Fukuda, H. Utsunomiya, T. Sakai, Y. Saito& N.

Furushiro, Materials Science Forum (2003) 426‑432 2649.

Texture evolution in accumulative rolled bonded Mg-Nb composites from polycrystal to single crystal layers Daniel J. Savage1, Irene J. Beyerlein2, Rodney J. McCabe3, John S. Carpenter3, Nathan A. Mara3, Sven C. Vogel3, Nan Li3, Marko Knezevic1 1University of New Hampshire, Durham, US. 2University of California, Santa Barbara, US. 3Los Alamos National Laboratory, Los Alamos, US.

Phase interfaces within interface-dominated, immiscible hexagonal

close-packed/body-centered cubic (HCP/BCC) materials can result in

an extraordinary combination of strength and ductility, a significant

improvement compared to those of the constituent phases. This

paper demonstrates the potential to convert a Mg alloy sheet with

poor formability and strength into a much more formable and

stronger material when it is processed into an ultrafine-layered

bimetallic sheet. To this end, the severe plastic deformation

technique accumulative roll bonding was used to refine stacks of

high-purity BCC Nb and HCP 4-5wt% Mg alloy sheet from mm to um

size layer thicknesses. To offer insights into the role of temperature

and strain-rate in large strain rolling of Mg based multilayer

composites, we present the evolution of microstructure, texture and

strength of this unique material for several processing paths.

Texture and Microstructure of Laser Butt-Welded AZ61Mg/Ti clad sheet H. Inoue and M. Okuno Osaka Prefecture University, Sakai, Japan.

We successfully fabricated a titanium-clad magnesium alloy sheet by

using warm roll-bonding and subsequent annealing as a candidate of

new lightweight materials. In order to apply this material to a

practical use such as a welded pipe and a large panel, laser butt

welding was performed for a two-layer AZ61Mg/Ti clad metal sheet

consisting of AZ61 magnesium alloy and Grade 1 titanium which

have very different melting points. The two-layer structure that was

characteristic of the clad metal were maintained even in the weld

zone after laser butt welding. The magnesium alloy and titanium

layers around an interface of the base metal exhibited equiaxed

recrystallized grain microstructure and nearly equiaxed grain

microstructure including deformation twins, respectively. In

contrast, the magnesium alloy and titanium layers of the weld zone

showed coarse solidified structure elongated parallel to nearly the

thickness direction and microstructure consisting mainly of coarse

grains, respectively. Laser welding changed texture of the titanium

layer from the TD-split type rolling texture with basal planes inclined

toward the transverse direction to the transformation texture with

various β to α transformed orientations on cooling. On the other

hand, basal texture of the magnesium alloy layer was changed to a

near {-1 2 -1 0} <0001> orientation as a main component by laser

welding. This suggests that the texture evolution would be

attributed to the direction of grain growth during solidification.

Relationship between Initial Hydrogen Absorption Properties and Microstructures of Mg/Cu Super-Laminate Composites with Different Accumulative Roll Bonding Cycles K. Tanaka1, D. Nishino2, 3, R. Kondo2 and H.T. Takeshita2 1National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Japan. 2Kansai University, Suita, Japan. 3Lawson Inc., Tokyo, Japan.

Magnesium has been considered as a good candidate for hydrogen

storage applications, because of its high hydrogen storage capacity

(7.6 mass %), low cost, light weight and high abundance in the

earth’s crust. Moreover, MgH2 has other attractive properties, such

as reversibility of hydrogen absorption/desorption and recyclability.

The main drawbacks for the use of MgH2 are slow hydrogen

absorption/desorption kinetics and high temperatures of operation

(> 573 K) associated with its strong thermodynamic stability. To

solve these problems, many efforts have been made recently, such

ABSTRACTS WEDNESDAY AM - ENGINEERING 73

as appropriate alloying of magnesium, adding catalysts, and

manufacturing nano-crystalline powder.

Mg/Cu super-laminate composites (SLCs) (Mg2Cu composition)

made by accumulative roll bonding (ARB) show fast kinetics and

good durability of hydrogen absorption/desorption compared with

Mg2Cu powder. We have reported the improvement of hydrogen

absorption/desorption kinetics, its relations with microstructures,

and the effect of initial structures of Mg/Cu SLCs on hydrogen

absorption/desorption properties in previous papers for Mg2Cu-H2

system.

During initial hydrogenation, hydrogenation of Mg and alloying Mg

with Cu followed by hydrogenation of Mg2Cu occur competitively. It

is reported that sever plastic deformation (SPD) such as high-

pressure torsion (HPT) and equal-channel angular pressing (ECAP)

can enhance atomic diffusion and promote solid-state reactions

because of an increase in the density of lattice defects such as

vacancies, dislocations and grain boundaries. It is important to know

the effect of ARB.

In this paper, we examined the relationship between initial

hydrogen absorption properties and microstructures of Mg/Cu SLCs

with different cold-rolling cycles.

Three types of specimens were prepared by changing ARB cycles.

They were cold-rolled with 10, 20, and 30 cycles, respectively.

Hydrogen absorption properties were measured with a Sieverts’

type instrument. Microstructures such as the thickness of Mg and Cu

layers and dislocations were observed with SEM and TEM. The

formation mechanism of microstructures in Mg/Cu SLCs during

initial hydrogenation through competitive reactions was estimated

by evaluating the activation energy for the layer growth process of

Mg2Cu in Mg/Cu SLCs.

The activation energies did not show a significant difference

between Mg/Cu SLCs with different ARB cycles. However, the

average thickness of Mg + Cu layers in as-rolled Mg/Cu SCLs became

thinner as the ARB cycle number increased. Initial hydrogen

absorption properties and microstructures of Mg/Cu SLCs after

initial hydrogenation were very different between Mg/Cu SLCs with

10 ARB cycles and over 20 ARB cycles. Hydrogenation of Mg was

major in Mg/Cu SLCs with 10 ARB cycles and that of Mg2Cu over 20

cycles. From the above, it is considered that the fineness of

microstructures in as-rolled Mg/Cu SLCs has large influence on initial

hydrogenation properties and microstructure formation processes.

Influence of Texture on Layer stability in Ti/Al ARB Composites J. Scharnweber1, J. Romberg2, C.-G. Oertel1, J. Freudenberger2, L. Schultz2 and W. Skrotzki1 1Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden, Germany. 2Leibniz-Institut für Festkörper- und Werkstoffforschung, D-01171 Dresden, Germany.

Ti/Al laminated sheets have been produced by Accumulative Roll

Bonding (ARB [1]) at ambient temperature, both with and without

intermediate annealing. A maximum of eight and six ARB cycles was

conducted, respectively.

Without annealing, pronounced shear banding across the layers

commonly observed in ARB composites [e.g. 2] occurs after few ARB

cycles. This transforms the layered structure into an Al-matrix with

embedded Ti-fragments. During subsequent ARB processing the

thickness reduction of the latter becomes very inhomogeneous

being overall significantly retarded compared to the geometrical

reduction of the sheet. An annealing of 90 minutes at 450°C in

between rolling cycles was found to promote homogeneous

deformation of both phases during ARB resulting in Ti/Al-composites

with stable layers with a minimal spacing of about 4 µm after eight

ARB cycles [3].

The evolution of microstructure and local texture of both Al and Ti

was studied by electron backscatter diffraction, the bulk texture was

measured by neutron diffraction.

It was found that during intermediate annealing recrystallization

occurs in both Al and Ti retarding microstructural refinement. The

bulk texture of Al is dominated by S, copper/Dillamore and brass

components. With intermediate annealing each rolling and

annealing step strengthens and weakens the rolling components,

respectively. In Ti, the usual 30°-tilt of the c-axis around the rolling

and towards the normal direction was observed with maxima at

either <10-10> or <11-20> being parallel to the rolling direction.

During the intermediate annealing, the latter component becomes

dominant.

The talk will focus on the microstructural and textural evolution with

regard to annealing temperature and ARB cycle, respectively. The

influence of texture on layer stability will be discussed and

compared to that of other factors, e.g. the hardening rate.

Acknowledgment: Thanks are due to Dr. W. Gan (FRM II, TUM) for

experimental support. Financial support by Forschungs-

Neutronenquelle Heinz Maier-Leibnitz (FRM II) is gratefully

acknowledged. The work has been carried out within the Saxon

Excellence Cluster “European Centre for Emerging Materials and

Processes (ECEMP)”.

[1] Y. Saito, H. Utsunomiya, N. Tsuji & T. Sakai (1999) Acta Mater. 47 579.

[2] D. K. Yang, P. Cizek, P. Hodgson & C. Wen (2010) Scripta Mater. 62 321.

[3] W. Skrotzki, A. Eschke, J. Romberg, J. Scharnweber, T. Marr, R. Petters, I. Okulov, C.-G. Oertel, J. Freudenberger, U. Kühn, L. Schultz & J. Eckert (2014) Adv. Eng. Mater. 16 1208.

Deformation behavior and strength of bulk Zr/Nb nanolayered composites Daniel J. Savage1, Irene J. Beyerlein2, Rodney J. McCabe3, John S. Carpenter3, Nathan A. Mara3, Sven C. Vogel3, Nan Li3, Jordan Weaver3, Marko Knezevic1 1University of New Hampshire, Durham, US. 2University of California, Santa Barbara, US. 3Los Alamos National Laboratory, Los Alamos, US.

In this work, we report on the deformation behavior and strength of

two-phase 50/50 Zr/Nb nanolayered composites after cold rolling to

a range of rolling reductions. The starting material is a bulk sheet of

Zr/Nb layered composite made by accumulative roll bonding with a

ABSTRACTS WEDNESDAY AM - ENGINEERING 74

nominal individual layer size h = 92 nm. Final layer thicknesses after

cold rolling were on the order of 5 nm. Substantial edge cracking

was observed during rolling of sheets with h > 41 nm, but was

minimal for h < 41 nm. Transmission electron microscopy and

neutron diffraction reveal a continuous layered structure of hcp-Zr

and bcc-Nb and a weakening texture h < 41 nm. Nanoindentation

hardness, spherical indentation, and micro pillar compression

indicate a non-decreasing increase in strength with decrease in h,

with the finest material achieving a strength of at least 1.5 times

that of the coarse-layered Zr/Nb composite and an order of

magnitude increase in strength over that of either constituent. The

results offer insight into interface driven deformation mechanisms

relevant for the microstructural design of hcp-based nanolaminates.

ABSTRACTS WEDNESDAY AM - CHARACTERIZATION 75

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National Laboratory

Concurrent in situ HREBSD and HRDIC analysis of an AlCu oligocrystal using selectively electron transparent microstamping Tim Ruggles1, Jake Hochhalter2, Andrew Cannon3, Geoff Bomarito2 1National Institute of Aerospace. 2NASA Langley Research Center. 31900 Engineering

HREBSD (high resolution electron backscatter diffraction) and HRDIC

(high resolution digital image correlation) methods provide

complementary information valuable for understanding

deformation at the microscale, namely local elastic strain and local

total strain respectively. However, conventional patterning

techniques required for HRDIC disrupt the diffracted electrons

generated for HREBSD, making concurrent analysis via these two

techniques at the same length scale problematic. A new technique

is introduced here to combine these two techniques in situ:

urethane rubber microstamping. Microstamping applies a thin,

amorphous polymer pattern that is thin enough to be effectively

transparent to the high energy (20 keV) diffracted electrons,

meaning that electron backscatter diffraction patterns suffer no

measureable loss of detail. At the same time, the patterns are still

thick enough to be imaged at lower accelerating voltages for HRDIC.

Results from concurrent HREBSD and HRDIC performed on an AlCu

oligocrystal tensile specimen deformed in situ will be presented.

Effect of grain orientation on hydrogen embrittlement of high manganese steel Daehwan Kim and Chong Soo Lee

Graduate Institute of Ferrous Technology, Pohang University of Science and Engineering, Pohang, Republic of Korea.

This study aims to investigate dependence of hydrogen

embrittlement characteristics on grain orientation of high

manganese steel. Single crystal micropillars were fabricated by

focused ion beam (FIB) and electron backscatter diffraction (EBSD) in

the grain matrix which orientation is the major texture component

of fcc; Goss, brass, copper, cube, E, and F. Hydrogen was charged

into micropillar by cathodic charging method. Compression tests

using nanoindenter were followed for uncharged- and hydrogen-

charged micropillar. Scanning electron microscope (SEM) and

transmission electron microscope (TEM) analysis were conducted for

microstructure evolution characterization. The flow behavior of

micropillar varies with hydrogen charging and grain orientation.

Corresponding to hydrogen enhanced localized plasticity (HELP)

theory, lowered yield strength and early onset of plastic

deformation occurred in hydrogen-charged micropillar.

Twinning and slip activity differ with grain orientation or fiber, which

leads to anisotropic behavior in hydrogen-charged condition. From

this study, grain orientation which causes incompatibility and

decohesion on the grain boundary is defined and possibility of

macro-texture control which enhances hydrogen embrittlement

resistance is proposed.

3D EBSD Characterization of Al5083 Spall Damage T. Sano1, J. P. Ligda, T. R. Walter, and C. L. Williams U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, USA.

Spall cracks in aluminum 5083 plates were formed by a high strain

rate plate impact experiment. To characterize the deformation and

spall cracks in 3D, two multi length-scale characterization techniques

were applied. The first was to non-destructively characterize a

region of interest with micro x-ray computed tomography (micro-

CT), and secondly, destructively serial section the same region,

incorporating electron backscattered diffraction (EBSD) with a

femtosecond laser coupled to a focused ion beam. The EBSD dataset

is reconstructed into a 3D volume, and the results combined with

those of the micro-CT to fully describe the spall damage.

Crystal Orientation Examination of Patterns Formed by Micro-indentation of Cube-textured Aluminum Foil Using SAXS and Temperature Changes S. Saimoto1, M. A. Singh2, M. R. Langille1 and C. Gabryel1

1Mechanical and Materials Engineering, Queen’s University, Kingston, ON. Canada, K7L3N6. 2Physics, Eng. Physics & Astronomy, Queen’s University, Kingston, ON Canada, K7L3N6

Recent use of nano-indentation to assess work-hardening of

complex microstructures of dual phase steels as a function of

deformation, together with crystal plasticity finite element methods

to simulate the bulk properties, gives rise to the question of the role

of crystallite orientation during indentation. Such studies using

nano-indentation on µm-sized grains are difficult. To elucidate the

role of possible parameters, micro-indentation of cube textured Al

capacitor foils were examined. These foils of 106 µm thickness are

convenient for small angle X-ray scattering (SAXS) examination and

the orientation around the indent can be examined by back-

scattered electron diffraction (EBSD). Moreover, the deformation

around the indent can be assessed to confirm the existence of

rotated lattice structures analogous to those observed near µm-

sized particles within the matrix. Due to the cube orientation, the

indents can be formed with the diagonal of the Vickers indenter

parallel to <100> or <110> directions. For an isotropic plastic

material, the diagonal lengths Ld should be √2, that of the width

between the parallel interface traces Lw, that is Ld / Lw = 1.41. The

indentations at various temperatures up to 160°C show that this

ratio is more or less constant for the <110> orientation but larger

than that for <100> one. Ratios approaching isotropy is found for

<100> at 80° and 120°C. The reason for the anisotropy is because of

the variation in latent hardening with different intersecting slip

systems and the resulting formation of stacking fault tetrahedral

which recovers above room temperature. These results together

with the lattice findings using SAXS will be described.

ABSTRACTS WEDNESDAY AM - CHARACTERIZATION 76

Study of the microstructure of a cold rolled interstitial free steel through X-Ray Diffraction and Electron Back-Scatter Diffraction E. A. Benatti1, N. S. De Vincentis1, M. Avalos1, H. G. Brokmeier2, N. Schell3 and R. E. Bolmaro1 1Laboratorio de Ciencia de los Materiales, Instituto de Física Rosario CONICET-UNR, Rosario, Argentina. 2Institut für Werkstoffkunde und Werkstofftechnik, TU Clausthal, Clausthal-Zellerfeld-Helmholtz-Zentrum Geesthacht, GEMS Outstation, Hamburg, Germany. 3Helmholtz-Zentrum Geesthacht, GEMS-Outstation DESY, Hamburg, Germany.

Hot and cold rolling are used for large-scale industrial processes, and

can produce a rather complex intermixing of grain refinement,

dislocation arrays and stacking faults, distorting the crystallographic

lattice and interfering with the motion of other defects. X-Ray

Diffraction (XRD) allows a global characterization of the

microstructure, through the analysis of the height and shape of the

diffraction peaks. Moreover, synchrotron XRD enables such analysis

in relation with the sample orientation. Electron Back Scatter

Diffraction (EBSD) studies, on the other hand, allows a more direct

although local kind of study. In this work we use XRD to determine

the texture of an Interstitial Free Steel, cold rolled to 70 % reduction,

and relate the measured texture with the defect storage on different

texture components through diffraction peak broadening analysis.

To that end we create Generalized Pole Figures (GPF) of Full Width

Half Maximum (FWHM), and use the pole figure to ODF inversion

method in the FWHM GPFs to find a generalized Orientation

Distribution Function (ODF) which can be compared with the regular

ODF used in texture analysis. Finally, we compare these results with

EBSD measurements of the same sample to obtain a more direct

estimation of the anisotropy of the defect storage of the sample. We

found that the gamma fiber, usually present in rolled BCC materials

is the component which tend to store more defects, although X-Ray

diffraction methods fail to distinguish which kind of defects are the

ones being stored. The typical alpha fiber was also found but it was

rather cleaner from defects. Both results are in agreement with

previous literature results for similar materials.

Characterization of local plastic strain during deformation from electron backscatter diffraction data – limitations and possibilities A. Godfrey, X. Hong, C.L Zheng Laboratory of Advanced Materials (MoE), School of Materials Science and Engineering, Tsinghua University, Beijing, China.

A critical review of the use of electron backscatter pattern

diffraction (EBSD) for investigation of deformed microstructures will

be presented. In particular, a comparison of grain scale and local

scale measures of plastic displacement, based on vertex tracking and

digital image correlation, with several misorientation-based EBSD

parameters will be given. The non-unique relationship between local

misorientation (on the scale of the deformation microstructure) and

plastic strain will be highlighted, as will some potential limitations of

commonly used measures for characterization of deformed

microstructures that arise as a result of the high spatial resolution

available with modern EBSD systems. Examples will be given from in-

situ tensile deformation of both FCC and HCP metals.

ABSTRACTS THURSDAY AM - PLENARIES 77

THURSDAY AM PLENARY SESSION

Advanced parent reconstruction: an efficient tool to optimize TMTs by a better control of the parent and subsequent inherited microtexture L. Germain1,2, N. Gey1,2 and M. Humbert1 1LEM3, University of Lorraine, Metz France. 2Laboratory of Excellence for Design of Alloy Metals for Low-mass Structures (‘DAMAS’ Labex), University de Lorraine, France

Optimizing the microstructure in a material which undergo a phase transformation during the thermomechanical treatment requires the control of

both the parent and the child microstructure. In this framework, the reconstructions of the parent microtexture from EBSD maps measured on the

transformation product have been proven to be very useful. Indeed, in many cases, such a method gives access to essential characteristics of the

parent microstructure: Crystallographic texture, grain size, local orientation spread (with an angular resolution of 1.5-3°), deformation mechanisms,

deformed/recrystallized fraction... [1]

In this presentation, the main principles of our reconstruction tool 'MERENGUE 2' and its benefits are recalled [2]. Several application examples are

presented, especially in Titanium and in martensitic and bainitic steels. Finally, the simultaneous knowledge of the parent and child microtextures

allows a finer analysis of the transformation mechanisms. In this framework 'DECRYPT' software (Direct Evaluation of CRYstallographic Phase

Transformation) has been developed. It is dedicated to analyzing the orientation data inherited by OR-based phase transformations. It is illustrated

on different application examples to assess variant selection mechanisms at a local scale: variant clustering in Steels, selective grain boundary

precipitation in Titanium...

[1] L. Germain, N. Gey, R. Mercier, P. Blaineau & M. Humbert, Acta Mater. (2012) 60, 4551–4562. [2] Merengue2, Software, http://lionelgermain.free.fr

The Texture Between the Grains: Statistics of Grain Boundaries and Grain Boundary Networks Christopher A. Schuh Department of Materials Science and Engineering, MIT, Cambridge MA USA

The treatment of crystallographic texture has become very advanced, with a mathematical toolkit developed to the point where inverse design

problems in texture control are possible and increasingly realizable. By contrast, the control of “grain boundary textures”, i.e., the distribution of

interface crystallographies in polycrystals, is certainly less developed, although such “grain boundary engineering” has an extremely strong value

proposition in improving many material properties. This talk will review progress over the past decade or so on the tools used to visualize and

mathematically describe grain boundary distributions. With an understanding of the misorientation space topology and symmetries, some

simplified mathematical constructs become possible, and some special cases from within the full 5-parameter space also exhibit satisfying

topological properties. With a spectral representation of misorientations, it is possible to treat more complex microstructural features, such as the

well-known short-range correlation of misorientations imposed at, e.g., triple junctions. And finally, by handling the emergent distributions of

microstructural ‘units’ such as triple junctions, a path to defining a complete “grain boundary network space” has now been opened. Although

early in their development, such approaches lead naturally to the posing of inverse problems in grain boundary network design for optimum

properties. The talk will end by projecting the trajectory of these recent developments forward in time, to identify opportunities for major new

future contributions.

ABSTRACTS THURSDAY AM - DEFORMATION 78

Symposium D: Deformation Textures Session: Advanced Materials

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Role of crystal orientation on deformation of Zr: A Molecular dynamics study K V Mani Krishna, D Srivastava and G K Dey Bhabha Atomic Research Centre, Mumbai, India

Plastic deformation is known to be highly orientation sensitive. This

orientation sensitivity of deformation gets further accentuated in

case of hexagonal materials. Present study is an attempt to bring out

the role of crystal orientation on the dislocation nucleation behavior

of Zr (hcp material). The role of crystal orientation, deformation

temperature and sense of loading (i.e. tensile vs compressive

deformation) on dislocation nucleation were studied. Nano

indentation simulations were used for modeling the heterogeneous

nucleation. More than 35 crystal orientations (representing various

loading directions) covering large portion of fundamental zone of

hcp symmetry have been used to bring out the quantitative

information of critical stresses for dislocation nucleation in case of

homogenous and heterogeneous dislocation nucleation.

Simulations have brought out high degree of orientation

sensitiveness in dislocation nucleation stresses in case of both

homogenous and heterogeneous nucleation events. Simulations

have shown that it is easier to nucleate <a> type dislocations than to

induce dislocations with burgers vector having <c> component. This

is in agreement with the experimental observation of higher density

of <a> type dislocations in comparison to <c> type in Zr. However,

no orientation had resulted in the formation of <c+a> dislocations

indicating that experimentally observed <c+a> dislocations could be

due to interaction of existing <a> and <c> type of dislocations. The

dislocation loop structure of heterogeneously nucleated loops

differed considerably with that of those that got homogenously

nucleated. While the former have grown in size with deformation,

latter have essentially increased in number density but not in size

with increase in deformation.

Texture evolution modeling of Ni alloys by crystal plasticity including twinning M. Ito1 and C.A. Schuh2 1Mitsubishi Materials Corporation, Kitamoto Saitama, Japan. 2Massachusetts Institute of Technology, Cambrige MA, USA

The texture evolution during the deformation of Ni alloys are

evaluated using crystal plasticity. We incorporate twinning

deformation within the crystal plasticity framework in order to

simulate both the Cu-type texture of rolled pure Ni and the Brass-

type texture of rolled Alloy C22. The calculation results have very

similar characteristics in their crystal orientation distributions to the

experimental results. The relationship between material model

parameters and the stacking fault energy are discussed as it pertains

to texture evolution.

Texture evolution in clock-rolled Zr during dynamic extrusion J.P. Escobedo1, CP Trujillo2, E.K. Cerreta2, R.A. Lebensohn2, GT Gray2 1UNSW Canberra, Canberra, ACT, Australia. 2MST –8, Los Alamos National Laboratory, Los Alamos NM, USA

The mechanical response and associated texture evolution in clock-

rolled Zr during dynamic tensile extrusion have been investigated.

Bullet-shaped specimens were tested in a modified Taylor-anvil

apparatus with their extrusion direction aligned to either the in-

plane (IP) rolling or the through thickness (TT) direction of the plate.

The post extrusion microstructure and texture evolution were

examined using electron backscatter diffraction microscopy (EBSD)

and modeled using the visco-plastic self-consistent (VPSC) model.

Our results show that the extrusion deformation was accomplished

through collaborative interaction of twinning and slip and their

relative activity greatly depends on the initial texture. In addition,

twinning dominates the texture evolution during the early stages of

deformation; this resulted in the development of the (10-10)

extrusion texture in all samples, independent of the initial texture.

Texture as a guideline for XRD residual stress investigation B. Kania Insititute of Metallurgy and Materials Science Polish Academy of Sciences, Kraków, Poland

Presentation covers the results of two ongoing science projects,

combining the XRD texture and strain measurements at constant

penetration depth, modelling the texture-induced mechanical

anisotropy of engineering materials and a generalized least-square

fitting of the stress tensor. Compiled methodology of stress

investigation relies on materials texture data not only in the analysis

of strain-stress relationship, but also in the process of planning the

measurements by proper selecting of pole figures points for which

strains will be gauged. This allows effective characterization of stress

state in the thin films, graded samples, materials with pronounced

texture or materials strongly relating all of that issues. With

presented method it is possible to simplify the strain-stress analysis

to the point of reliably utilization of the simplest models for

materials initially exposing themselves as very complicated fields of

study.

Martensitic transformation, twin boundary and phase interface mobility of directionally solidified Ni-Mn-Ga alloys during compression by EBSD tracing Y.C. Dai, L. Hou and X. Li* State Key Laboratory of Advanced Special Steels (Shanghai University), Shanghai 200072, China

Directional solidified Ni-Mn-Ga alloy with orderly arrayed austenite

and non-modulated martensite (NM) was formed due to

ABSTRACTS THURSDAY AM - DEFORMATION 79

microsegregation between dendrite arm and interdendritic space,

leading to preferred orientation <001>A and <110>M coexistence at

ambient temperature. The stress induced martensite transformation

took place due to the increase of martensite transformation

temperature under step-wise uniaxial compression. The detwinning

progress accompanied with dislocation mobility was easy to carry on

the twin planes at 45° incline to compression axis, compared with

the twin planes paralleled to compression axis in the dominant

twinned groups. The martensite transformation and reorientation of

variants were investigated by electron backscattering diffraction

(EBSD) tracing.

ABSTRACTS THURSDAY AM – DEFORMATION 80

Symposium D: Deformation Textures Session: Steels – Hot Rolling

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Texture evolution of duplex stainless steel UNS S32205 under hot working conditions D. Lindell1, D. Martin1, B. Hutchinson1 and A. Kaijalainen2 1Swerea KIMAB AB, Stockholm, Sweden. 2Materials and Production Engineering, University of Oulu, Finland.

Rolled duplex stainless steels show pronounced anisotropy in

mechanical properties that originates from both morphology and

texture. Especially important is the relatively strong rotated cube

texture that develops in the ferrite phase. The sluggish

recrystallization behavior of the ferrite phase implies that the final

texture is strongly inherited from earlier process steps. Hence, the

cast structure and the overall prior temperature and strain history

need to be taken into account to accurately model ferrite texture

evolution in rolled material. The current work focuses on a simplified

case suitable for comparison with existing crystal plasticity models.

The material used in the study is a duplex stainless steel

corresponding to UNS S32205 produced by powder metallurgy and

hot isostatic pressing to provide a texture-free, fine grained and

equiaxed starting structure. Hot deformation was simulated in plane

strain using a Gleeble 3800 from which sub-sized impact toughness

specimens were prepared. The experimental textures are compared

to simulated textures using various crystal plasticity codes. The

anisotropy in impact toughness is discussed on basis of the

morphology, texture and compared to commercially cast and hot

worked material.

Texture evolution after dynamic recrystallization in Fe-Mn-Si steel T. Toyoda1, N. Sugiura1, N. Yoshinaga1, J. Tamori2, H. Miura2 1Nippon Steel & Sumitomo Metal Corporation, Steel Research Laboratories, Futtsu, Japan; 2Toyohashi University of Technology, Department of Mechanical Engineering, Toyohashi, Japan

In hot rolling processes of steel, various phenomena such as work

hardening, work softening, dynamic recovery, dynamic

recrystallization (DRX) and etc. leads to change microstructure and

mechanical properties. It is well known that multiple- or single-peak

work softening in the flow curves are induced by extensive

occurrence of DRX. The oscillation of the flow stress is, therefore,

closely related with the changes in the microstructure and texture

that strongly affects mechanical properties of steel. DRX behavior

and evolved microstructure sensitively changes by addition of

elements. Si is frequently employed to improve yield and tensile

stresses as well as thermal stability.

The effects of Si addition on hot deformation behavior and

microstructural evolution in Fe-1.5Mn-0.01Si and Fe-1.5Mn-0.5Si

(mass%) steels were precisely studied by means of EBSD. Fe-1.5Mn-

0.5Si steel showed less texture evolution and finer DRX grains

compared to those in the former one. These differences are

presumed to be the effects of retarded grain coarsening and

increased twinning by Si addition. In short, Si addition caused i)

solute drag effect to reduce grain-boundary migration, ii) higher

probability of twinning in phase to contribute to orientation

randomization.

Texture Changes of Electromagnetic Ferritic Stainless Steels by Compressive Deformation at High temperatures Y. Onuki1, S. Sato1, M. Uchida1, T. Naruse2, Y. Kim2, T. Ebata2, S. Fujieda3 and S. Suzuki3 1Ibaraki University, Ibaraki, Japan. 2Tohoku Steel Co., Ltd., Miyagi, Japan. 3Tohoku University, Sendai, Japan.

Precipitation-hardened ferritic stainless steels are used for

electromagnetic actuators of engines, as these steels reveal the high

strength and soft magnetic properties. The hardening of these

ferritic stainless steels occurs by formation of nanoscale precipitates

of NiAl in during aging after solution treatment. Furthermore, it is

required to control the texture of these steels, since it is known that

the soft magnetic properties are obtained in the ferritic steels with

<100> fiber texture. However, texture control of the ferritic stainless

steels has not been attempted so far. In this study, the texture

change in a ferritic stainless steel by deformation at high

temperatures. As it has been shown that the texture of ferritic Fe-Si

alloys is significantly changed by deformation conditions such as

temperature and strain rate [1], the compressive deformation

processes were applied to the texture control of the present

stainless steels.

Samples used were a ferritic steel of Fe-14.5Cr-3Ni-2Mo-1Al-1Si (in

mass%). The specimen for uniaxial compression deformation test

was a cylinder of φ10 x H15mm. They were compressed under

different strain rates at high temperatures between 973 and 1073 K.

The microstructure and texture of the deformed sample were

characterized by analyzing the cross section of the cylindrical

samples using electron backscatter diffraction (EBSD). The volume

fractions of <100> and <111> texture components in the sample

were mainly investigated in this work.

The texture analysis results by EBSD showed that the fraction of

<100> texture component increases with decreasing strain rate, and

reveals the maximum in the samples deformed at the strain rate of

5x10-4s-1.

The dependences of microstructure and texture on the deformation

condition seen in the current study is similar to what observed in the

previous studies [1, 2]. Namely, lower density of small angle grain

boundary and higher fraction of <100> oriented region are achieved

with lower strain rate. This suggests the activation of PDGG

(preferential dynamic grain growth). The PDGG is achieved by the

ABSTRACTS THURSDAY AM – DEFORMATION 81

strain-induced grain boundary migration due to the difference of

stored energies between different crystal orientations. Since <100>

has lower Taylor factor than <111>, another deformation texture

component during uniaxial deformation, lower dislocation density in

<001> than in <111> is expected. Therefore, it can be concluded that

<100> oriented grains expand by consuming <111> oriented grains

so that the total stored energy in the bulk is reduced. The current

result indicates that the PDGG can be applied as the texture

controlling mechanism not only in binary or ternary alloys but also in

practical alloy steels including various elements.

[1] Y. Onuki, R. Hongo, K. Okayasu & H. Fukutomi (2013) Acta Mater., 61, 1294.

[2] Y. Onuki, S. Fujieda, S. Suzuki & H. Fukutomi (2017) ISIJ Inter., 57, in press.

ABSTRACTS THURSDAY AM - TRANSFORMATIONS 82

Symposium T: Transformation Textures Symposium Chair:

Dr. Michael Roach, Biomedical Materials Science, University of Mississippi Medical Center

Analysis of texture memory, surface-effect-induced transformation texture and variant selection in low graded electrical steels P. Yang, C. Gu, N. Wang, J. Wang and W. Mao School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, China, 100083.

The textures in commercial non-oriented electrical steels are all

optimized by the control of deformation and recrystallization

parameters irrespective of their grades or silicon contents. The

favorite {100} texture in such condition takes at maximum only

about 20% in volume fraction. In contrast phase transformation

combined with deformation can lead to nearly 80% volume fraction

of {100} oriented grains which is confirmed by many authors.

Texture memory effect is often detected in steels during

transformation influenced by rolling process. Yet texture memory

does not equal to the presence of strong transformation texture, it is

often seen that transformation texture is quite different to the

rolling texture of ferrite before transformation. If transformation

proceeds uniformly in steel sheets, {111} texture or nearly random

texture can also be resulted; If it takes place by nucleation at sheet

surface in pure hydrogen after rolling, strong {100} texture can be

obtained, so that magnetic properties can be improved.

Based on the fact that strong {100} texture can be produced by

rolling and subsequent transformation annealing in low grade

electrical steels, this work aims to investigate the degree of texture

memory during transformation in cast slabs of low grade

electrical steels containing dominant columnar grains and its

influence on subsequent rolling and transformation annealing. The

purpose of this study is to provide fundamental principles for the

potential application of low grades of non-oriented steels.

The EBSD measurement on ferritic columnar structure of cast slabs

at room temperature reveals that about 70% regions are columnar

grains with nearly {100} orientations and 30% are small equal-axed

grains formed within coarse columnar grains manifesting a texture

memory effect without the influence of external deformation. A lot

of 3 misorientations are present between coarse columnar grains

and small grains indicating the K-S orientation relationship and the

variant selection rule of reducing transformation strain as much as

possible. However, there are still a lot of small grains which don’t

share special misorientations with surrounding grains. The formation

of this kind of grains is attributed to the austenitic variants formed

during the first transformation or the orientation fluctuation

caused by deformation during casting. As early 70% columnar

grains are retained during cooling of cast slabs without the influence

of external deformation, it is seen that the thermal stress needed for

variant selection, which is produced during cooling, is rather low.

Texture memory in AISI 321 austenitic stainless steel A.A. Tiamiyu, J.A. Szpunar and A.G. Odeshi University of Saskatchewan, Saskatoon, Canada.

In this study, AISI 321 austenitic stainless steel was cryo-rolled at -

196 ℃ to 50 % thickness reduction to completely transform the γ-

austenite phase to αʹ-martensite. The cryo-rolled sample was

subsequently annealed in the temperature range of 650 – 800 ℃ for

0.5 – 480 minutes to reverse the αʹ-martensite back to γ-austenite

and develop ultrafine grain (UFG) structure at an optimum annealing

condition. Although the mechanism of reversion in 600 ℃-annealed

specimen is different from those of higher temperatures, high

resolution EBSD and XRD texture results shows that ζ-fibre

({110}<uvw>) is the major texture component of austenite grains in

the UFG structure and it is stronger at 650 ℃ than higher

temperatures (700, 750 and 800 ℃) used in this study. The strong

intensity of ζ-fibre in UFG is attributed to texture memory in AIS 321

i.e. the ability of the steel to memorize the crystallographic

orientation of the deformed austenite, rather than the conventional

as-received austenite phase that is random. TiC precipitates which

are more stable at 650 ℃ than 700, 750 and 800 ℃ and unreversed

triple junction αʹ-martensite played a major role in the development

of UFG structure by Zener pinning of grain boundaries. Average

austenite grain sizes of 0.22 and 0.31 microns were obtained at an

optimum annealing conditions of 650 ℃ for less than 480 minutes

and 750 ℃ for 10 minutes, respectively.

Crystallographic Texture and Microstructural changes in a weld of two Zry-4 plates: Variant selection Model A Moya Riffo, M.A. Vicente Alvarez and J.R. Santisteban Neutron Physics Department - Bariloche Atomic Center - CNEA-CONICET, S.C. Bariloche, Argentina.

This work presents a detailed description of the microstructural and

crystallographic texture changes observed in the transition region in

a weld between two Zircaloy-4 cold rolled and recrystallized plates

[1]. In the heat affected zone (HAZ) we observed the development of

Widmanstätten microstructures, typical of the α(hcp) to β(bcc)

phase transformation. Associated with these changes a rotation of

the c-poles is found in the HAZ and fusion zone. While the base

material shows the typical texture of a cold rolled plate, with their c-

poles pointing 35º apart from the normal direction of the plate in

the normal-transversal line, in the HAZ, c-poles align along the

transversal direction of the plate and then re-orient along different

directions, all of these changes occurring within a length scale in the

order of mm.

The microstructural and texture changes along the HAZ were

interpreted as arising due to the effect of differences in the cooling

rate and β grain size on the progress of the different α variants

during β−•α transformation. Fast cooling rates and large β grains are

associated to weak variant selection during the β−•α

transformation, while slow cooling rates and fine β grains result in

strong variant selection. Also in a particular region of the HAZ,

where phase transformation was incomplete, a texture memory

effect was evidenced.

ABSTRACTS THURSDAY AM - TRANSFORMATIONS 83

A theoretical model was proposed to describe the origin of the

variant selection mechanism. This model is based on the evaluation

of the energy advantage for nucleation of α embryos in an infinite β

matrix associated to the interaction between the transformation

strain misfit and the elastic response of the texture medium [2]. The

model was able to reproduce the observed textures after the β−•α

transformation, and also the changes on this texture due to

differences in the cooling rate.

[1] A. Moya Riffo, et al., Journal of Nuclear Materials (2017), http://dx.doi.org/10.1016/j.jnucmat.2017.02.015

[2] M. Humbert and N. Gey, Acta Materialia. 51 (2003) 4783–4790.

The effect of cold work on the texture of a Zirconium alloy after fast β-cycling C-T. Nguyen1, J. Romero2, A. Ambard3, M. Preuss1, J. Quinta da Fonseca1 1Materials Performance Centre, The University of Manchester, Manchester, UK. 2Westinghouse Electric Company, Columbia, South Carolina, USA. 3EDF R&D, Centre de Renardière, Moret-sur-Loing, France

The texture of cold worked zirconium nuclear fuel cladding after the

rapid β-heating cycle, characteristic of loss-of-coolant and reactivity-

initiated accidents (LOCA and RIA), is different from that of the

material that starts off in the recrystallized condition. Whereas the

final α-texture of the cold-worked sample is essentially random, that

of the recrystallized material is a much stronger with 0002 poles in

transverse direction. The aim of the work reported here was to

understand the origin of this effect.

Electrical resistivity was used to measure the kinetics of the phase

transformation during the fast β-cycle, which had the heating rate of

100ºCs-1, the maximum temperature of 1100ºC with holding for 3

seconds and the cooling rate of 50ºCs-1. This thermal cycle was

achieved via resistive heating in an electro-thermal-mechanical

tester (ETMT), which also ensured no stress was applied. EBSD was

used to measure the textures before and after transformation and

synchrotron X-ray diffraction was used to measure the texture

evolution during the cycle.

The experiments showed that cold-worked samples transform at

higher temperature and have lower β volume fraction at a given

temperature than the recrystallised samples. The reconstructed

high-temperature β texture after β-grain growth of the cold-worked

material was found to be much weaker than that of the

recrystallised. The in-situ measurements show there is a difference

in the transformed β-textures during phase transformation

αα+ββ of the two materials and this difference emerges more

during β grain growth.

By comparing the experimental α-textures and predicted ones

without variant selection on cooling, it can be shown that this

difference in β texture could explain most of the differences in the

transformed texture. Furthermore, when the material starts in the

recrystallized condition, there is evidence of increased variant

selection on cooling.

These differences in the kinetics of phase transformation, the final

α-textures, the reconstructed β textures and the variant selections

in the two conditions can be explained by the different textures and

grain boundary network, on which the new phases preferably

nucleate, just before the phase transformation. These findings will

improve the accuracy of inputs from microstructure and texture of

zirconium claddings to LOCA/RIA models. They also suggest that cold

work can have a very different effect on phase transformation

textures from those previously reported for titanium alloys with

similar crystal structures.

Texture Evolution during Hot-Rolling of Dual Phase Zirconium Alloys

C.S. Daniel1, P.D. Honniball2, L. Bradley2, M. Preuss1 and J.Q.

Fonseca1

1University of Manchester, Manchester, United Kingdom. 2Rolls-Royce plc, Derby, United Kingdom.

Dual-phase α + β Zr-Nb alloys have a higher strength and fracture

toughness than single phase α-alloys and develop different textures

during thermo-mechanical processing. Dual-phase Zr-alloys tend to

form a strong transverse (TD) texture of the basal pole, the origin of

which is poorly understood and cannot be predicted by crystal

plasticity texture evolution models. This is probably because the

microstructure and texture evolution of these dual-phase alloys

arises from complex interactions between the α (hexagonal-close-

packed, hcp) and β (body-centred-cubic, bcc) phases, during both

deformation and phase transformation.

The work presented here is an investigation of the texture evolution

in an industrially used Zr-2.5Nb alloy during hot-rolling. The aim was

to determine the relative roles of plastic strain partitioning between

phases, the activity of the different deformation modes and phase

transformation on the final texture. The effect of temperature

(700 ℃ to 825 ℃), reduction ratio (50 % to 87.5 %) and strain

rate, along with the influence of starting texture, was characterised

using time-of-flight neutron diffraction and EBSD techniques. The

transverse texture component, with prismatic alignment {1120} <

1010 >, strengthens significantly with greater rolling reduction at

the higher temperature. Software reconstruction of EBSD

orientation maps, using the Burgers relationship, shows how the

strength of this texture component varies across the material

depending on the orientation of the large prior-β grains.

A more detailed characterisation of the high temperature

deformation and phase transformation behaviour was made on a

hot-rolled Zircaloy-4 + 7 wt.% Nb alloy. Since a greater proportion of

metastable βZr is retained to room temperature, a snapshot of the β → α phase transformation can be captured, distinguishing high

temperature primary α grains from the nucleation and growth of

secondary α variants. Previous work had shown that the strong

transverse texture of the transformed α is at least in part caused by

variant selection, with a mechanism determined by the high

temperature breakup of the prior-β grains. By analysing these

structures in 3D, using a plasma focused ion beam (PFIB) and taking

sequential EBSD slices, it was found that the degree of breakup is

affected by the distribution of primary α laths within each β grain.

Further analysis showed that the orientation of primary α influences

the breakup behaviour of the β grains, which then affects variant

ABSTRACTS THURSDAY AM - TRANSFORMATIONS 84

selection through preferential growth selection of secondary α upon

cooling. These findings suggest new ways in which current models

can be developed to enable the successful prediction of hot rolling

texture in these alloys.

ABSTRACTS THURSDAY AM - ENGINEERING 85

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Processing – Additive Manufacturing

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Anisotropy and Microstructure in 3D Printed IN 718 S. Subedi1, A. Palomares2, J. Molina-Aldareguía2, J. Llorca2,3, S. Cong1 and A.D. Rollett1 1Carnegie Mellon Univ., Pittsburgh, USA. 2IMDEA Materials Institute, Madrid, Spain. 3Polytechnic University of Madrid, Spain.

Additive manufacturing (AM) via 3D printing of metals has increased

in importance in a short space of time, largely because of the

demonstrated ability of powder bed machines to make parts

reliably. Nevertheless, there are many open questions relating to

microstructure, porosity, precipitation state and texture. Some of

these issues are illustrated from work on printing heat exchangers

for use with supercritical CO2 in Inconel 718 where the

microstructures exhibit strong orientation gradients, very low twin

densities and irregular grain shapes. The low twin densities are

consistent with previous work, which established that annealing

twins are created predominantly during primary recrystallization.

Unless heat treated, AM materials represent the result of direct

solidification albeit at cooling rates approaching 106 °/sec. The high

cooling rates allied with solidification, thermal shrinkage and creep

explain the residual plastic deformation. By milling out micro-pillars

in a polished surface and performing micro-compression tests, the

anisotropy of the material was investigated. The results suggest that

the strength is sensitive to the occurrence of single versus multiple

slip, as well as the presence of grain boundaries near the top of the

pillar.

In-situ Investigation of Microstructure Evolution during Annealing in Ti-6Al4V Alloy Produced by Additive Manufacturing S.C. Vogel1, S. Takajo1,2, A. Pesach3, O. Yeheskel3, E. Caspi3, E. Tiferet3 1Los Alamos National Laboratory, Los Alamos, NM, U.S.A. 2JFE Steel Corporation, Kurashiki, Japan.3Nuclear Research Center Negev, Israel

Selective laser melting (SLM) and electron beam melting (EBM) are

AM processes, in which three dimensional metallic objects are

obtained by melting the ingredient powder materials layer by layer.

Due to high solidification rates of small melt volumes, AM products

may result in off-equilibrium microstructures, in which macro-strain,

micro-strain and directional growth are present. However, recently

it was shown that, the micro-structure of the EBM sample is found

free of preferential orientation, whereas in the SLM sample

significant preference towards the hexagonal basal plane. Rietveld

analysis of our preliminary measurements (carried out at HIPPO,

LANL) on AM TiAl6V4 samples, produced by both SLM and EBM,

show a dependency between the AM process and the content of β-

phase and the strength of α-phase texture in post processed

samples. It was found that the weight percentage of the β-phase at

the end of one SLM process was ~10 times higher than in similar

samples that were produced with EBM or SLM with different

machine. We expand on the ambient condition measurements and

report also on our finding of the microstructure evolution during

annealing at temperatures up to 1100C.

Effect of Microstructure and Texture on the Elasto-viscoplastic Deformation of Dual Phase Titanium Structures Tugce Ozturk, Anthony D. Rollett Carnegie Mellon University, Pittsburgh, USA.

Ti-6Al-4V, one of the most popular titanium alloys used in direct

metal additive manufacturing (AM), exhibits highly heterogeneous

characteristics when produced by electron beam melting (EBM), an

established powder bed AM technique. The thermal gradient

accompanying this manufacturing process directly affects the

cooling rate of the melted powder, hence the resulting

microstructure and the mechanical properties. We present a

computational approach for creating a large structure-property

database for dual phase titanium alloys, through the use of a

synthetic microstructure generation method and a mesh-free fast

Fourier transform based micromechanical model that operates on

an image of the microstructure. 3D synthetic microstructures are

generated based on additively manufactured Ti-6Al-4V

characteristics, which are further modified to expand the database

for features of interest, e.g. different parent/daughter textures. Sets

of titanium hardening parameters are extracted from literature, and

the relative effect of the chosen microstructural features is

quantified through comparisons of average and local field

distributions. The response is found to be the most sensitive to

alpha phase fraction and the prior beta texture, such that the

increase in alpha phase enhances the tensile strength, and an

increased strength of prior beta (001) texture decreases the tensile

strength.

Texture development in steel components produced by Wire Arc Additive Manufacturing C. Goulas1, 2, 4, W. Ya3, 4, R.H. Petrov2, 5, M.C.M. Hermans2 and I.M. Richardson2

1Materials innovation institute, Electronicaweg 25, 2628 XD Delft, the Netherlands. 2Delft University of Technology, department of Materials Science and Engineering, Mekelweg 2, 2628CD Delft, the Netherlands. 3University of Twente, Chair of Applied Laser Technology, MS3 Department, Engineering Technology, P.O. Box 217, 7500 AE Enschede, The Netherlands. 4Rotterdam Additive Manufacture Fieldlab (RAMLAB), Scheepsbouwweg 8 - K03, 3089 JW, Rotterdam, The Netherlands. 5Gent University, Department of Materials Science and Engineering, Technologiepark 903, 9052 Zwijnaarde, Gent, Belgium

Wire and arc-based additive manufacturing (WAAM) processes are

novel technologies that are used for the construction of complex

large scale 3D-structures. WAAM is essentially a welding-based

technique, which means that WAAM products often exhibit

solidification microstructures. Solidification texture depends on the

ABSTRACTS THURSDAY AM - ENGINEERING 86

local heat flow directions and competitive grain growth in one of the

six <100> preferred growth directions. As WAAM products are

manufactured by layer-by-layer metal deposition, microstructural

and functional grading becomes possible by selection of appropriate

process conditions that determine the heat and material flow

direction. In this study, we demonstrate that through the variation

of deposition parameters and by applying external cooling, the local

heat flow can be controlled, which enables us to create desired local

texture by controlling the orientation of grain growth. Process data

and the thermal history of the locations studied, which is monitored

with a thermal camera, provide input for a better understanding for

controlling of the textures development during WAAM. For the

purpose of this study, vertical walls were deposited using low alloy

and austenitic stainless steel wires. Samples were cut from several

heights of these walls and were analysed by means of Electron Back

Scatter Diffraction (EBSD). A better understanding and control of the

solidification textures during WAAM process can help to improve

the product design, by taking into account the new possibilities of

manufacturing of additively manufactured functional materials.

Role of texture in tensile, compressive, cyclic, and fracture behavior of direct metal laser sintered Inconel 718 Saeede Ghorbanpour and Marko Knezevic Department of Mechanical Engineering, University of New Hampshire, Durham, NH 03824, USA.

This paper describes the main results from a comprehensive

investigation into the role of texture on strength and cyclic tension–

compression to large strains as well as low and high cyclic fatigue

behavior of direct metal laser sintered (DMLS) Inconel 718

superalloy. The results are reported for different initial

microstructures created by variation in the deposited direction. To

further investigate the effects of initial microstructure, a set of

samples underwent hot isostatic pressing. To have a reference for

the behavior of DMLS Inconel 718, a set of wrought Inconel 718

samples in the same condition was also tested, and the results

critically compared against the results for the DMLS materials. In

order to understand particularities pertaining to behavior of the

material at the grain-scale, a dislocation density based hardening

law is developed and used within elasto-plastic self-consistent

crystal plasticity model to simulate all the tests except the high cyclic

fatigue. The modeling results in conjunction with detailed

microstructural characterization reveal the significant role played by

porosity, annealing twins as well as reverse dislocation motion and

backstresses on the material behavior.

ABSTRACTS THURSDAY PM1 - BOUNDARIES 87

Symposium B: Misorientation Textures at Grain Boundaries and Interfaces Symposium Chairs:

Dr. Eric Homer, Department of Mechanical Engineering, Brigham Young University

Dr. Srikanth Patala, Department of Materials Science and Engineering, North Carolina State University

Grain Boundary Texture, Energy, and Curvature as a Function of Lattice Misorientation and Grain Boundary Plane Orientation X. Zhong, M.N. Kelly, and G.S. Rohrer Carnegie Mellon University, Pittsburgh, PA, USA.

Grain boundary properties depend on five independent

crystallographic parameters. Three can be associated with the

lattice misorientation and two with the grain boundary plane

orientation. Three-dimensional orientation mapping makes it

possible to measure grain boundary relative areas (texture), grain

boundary energies, and grain boundary curvatures as a function of

all five grain boundary parameters. Here, we describe techniques

for these measurements and present an over view of findings from a

variety of metals and ceramics. One of the general findings is that

the texture is stronger in the space of grain boundary plane

orientation than it is in the space of misorientations. Furthermore,

there are persistent correlations in materials that form by normal

grain growth. For example, the grain boundary energy and the grain

boundary population have an inverse logarithmic correlation. For

most types of boundaries (those that are non-singular), the mean

curvature has an inverse linear correlation to the grain boundary

energy. However, singular grain boundaries such as coherent twins

are characterized by low energy, low curvature, and high

populations. Examples will be cited from studies of Ni, bcc Fe, fcc

Fe, and SrTiO3.

Grain Boundary Plane Structure-Property Relationships and Fundamental Zones Eric R. Homer1, Srikanth Patala2, Jonathan Priedeman1, David Olmsted3 1Brigham Young University, Provo, USA. 2North Carolina State University, Raleigh, USA. 3University of California, Berkeley, USA.

A full crystallographic description of a grain boundary requires 5

parameters, 3 for misorientation and 2 for boundary plane

orientation. Typical characterizations focus on misorientation, but

boundary plane plays an important role in structure-property

relationships. The presented work focuses on describing the GB

crystallography, including boundary plane orientation, in

fundamental zones and demonstrates that structure-property

relationships naturally emerge from this form. Structure-property

relationships of energy, excess volume, and mobility are

demonstrated for a range of GB types. The fundamental zone

representation also suggests possible trends over the full 5D space

among similar disorientation axis grain boundaries. Finally, the

various mobility trends in Σ3 grain boundaries are explained in the

context of this fundamental zone representation.

Segregation Affecting the Evolution of Primary Recrystallization Textures in a Ternary Fe-Si-Sn Alloy N. Mavrikakis1,2, M. Dumont1, D. Mangelinck1, M. Descoins1, W. Saikaly3 1Aix-Marseille Université, CNRS, IM2NP UMR 7334, Marseille, France. 2ArcelorMittal Research SA, Maizières-lès-Metz, France. 3ArcelorMittal Global R&D Gent, Belgium

The effect of Sn addition on the primary recrystallization of cold

rolled Fe-3% Si alloys is investigated. Texture evolution and

misorientation distributions are analyzed on partially recrystallized

samples using the electron backscatter diffraction technique. Sn was

found to affect the microstructure, throughout the thermal

treatment of the materials, by refining the grains and altering the

texture. In the presence of Sn, the intensity of {111}<uvw> grains is

reduced through all stages of recrystallization, while that of

{100}<uvw> and {hkl}<100> grains is increased. The favored growth

of these latter grains is most likely due to a combination of

mechanisms that involve the presence of some high mobility grain

boundaries (with low Σ). Indeed, the Σ5 boundaries were observed

to increase in frequency with Sn through all stages of

recrystallization. Additionally {100} grains were found to be most

frequently correlated with Σ5 interfaces, which might be due to

geometrical considerations. The most probable explanation for the

increase of Σ5 is that Sn segregates to random high-angle grain

boundaries and retards their migration, whereas little segregation

takes place to the Σ5 boundaries, favoring the growth of grains that

are bounded by this boundary. Site-specific grain boundary Sn

segregation analysis was conducted with atom probe tomography to

confirm the proposed mechanism.

Inferring Grain Boundary Structure-Property Models from the Effective Properties of Polycrystals via Inverse Problem Theory C. Kurniawan, O.K. Johnson Brigham Young University, Provo, USA.

The structure and spatial arrangement of Grain Boundaries (GBs)

have been proven to strongly affect the properties of polycrystalline

materials such as corrosion, creep, weldability, superconductivity,

and diffusivity. The properties of GBs are typically correlated with

their crystallography via measurements conducted on bicrystals.

However, because of the high dimensionality of the GB spaces, the

use of this one-by-one approach to construct predictive structure-

property models is taxing, both experimentally and computationally.

We propose an efficient method to infer GB structure-property

models from measurements of the effective properties of

polycrystals. We provide an idealized case study in which a

structure-property model for GB diffusivity is inferred from noisy

simulation results in two-dimensional microstructures and the

accuracy of the inferred model is quantified.

ABSTRACTS THURSDAY PM1 - BOUNDARIES 88

Mechanisms of Grain Growth in 7 and 9 Grain Boundaries with Mixed Mobility Trends J.L. Bair1, E.R. Homer1 Brigham Young University, Provo, UT, USA

Grain boundary migration in 7 and 9 grain boundaries are

simulated at temperatures from 100 K to 1000 K under various

synthetic driving forces using Molecular Dynamics. The data are

analyzed using slip vectors, microrotations, and the Nudged Elastic

Band method to determine the mechanisms leading to mixed

mobility trends with respect to temperature. Analysis indicates that

an unchanging series of mechanisms controls grain growth in these

boundaries, with the slowest mechanism controlling the mobility

trend at a given temperature. Size effects of the mobility are

considered using various simulation cell sizes.

ABSTRACTS THURSDAY PM1 - PLENARIES 89

THURSDAY PM1 PLENARY SESSION

A model of grain fragmentation and microtexture evolution during plastic deformation Sivasambu Mahesh Indian Institute of Technology Madras, Chennai, India.

Plastic deformation of polycrystals is accompanied by two interdependent phenomena: texture development, and substructure formation.

Together, these phenomena determine the state of plastic anisotropy of the polycrystal. For a given deformation path, the texture determines the

set of favorably oriented slip systems in the grains, while the substructure determines the critical resolved shear stresses thereof.

A polycrystal plasticity model for fcc materials, wherein the texture and substructure are evolved simultaneously, will be described. Much attention

will be paid to the physical principles governing the orientation and spacing of the dislocation walls, of which the substructure is comprised. It will

be shown that there are two substructural length scales, which must be handled separately: (1) the larger scale of elements such as deformation

bands, and shear bands, which span the grain, and (2) the smaller scale of elements such as cell blocks, dense dislocation walls, and microbands. It

will be shown that although minimization of the plastic power underlies the formation of both scales of substructure, velocity continuity conditions

are preserved across elements of (1), but not across (2). Efficient computational schemes to include both types of sub-structural elements into a

polycrystal plasticity code will be mentioned. Predicted plastic anisotropy of fcc polycrystals with and without the substructural information will be

compared.

The Evolution and Quantification of Preferred Crystallographic Orientations in Wrought Titanium Alloys Using Traditional and Emerging Technologies B Wynne1, M Thomas2. 1Department of Engineering Materials, The University of Sheffield, Mappin Street, Sheffield, S1 3JD. 2TIMET UK, PO Box 704, Birmingham, B6 7UR.

Over the past fifty years the aerospace industry has chosen wrought alpha/beta and near alpha Titanium alloys for rotating aero-engine

applications. These alloys are often produced via cast ingot formed through multiple iterations of thermo-mechanical “work” into a near-net shape

component comprising bi-modal microstructures with between 15-35% refined equiaxed primary alpha grains in a matrix of a lamellar alpha

transformation product. A number of studies by prominent authors have shown that the major features within these microstructures that

determine the alloys static and fatigue strength are not only alpha grain size, shape and morphology but also the size, shape and orientation of

clusters of similarly orientated alpha features know as macrozones or micro texture regions (MTR’s). As such, significant work is currently being

undertaken to quantify macrozones, investigate their evolution during processing and define their effect of component properties.

Electron Back Scatter Diffraction (EBSD) is commonly used within both industry and academic institutions to assess microtexture in various titanium

alloys and some relevant examples will be shared here. However, the destructive nature of sample preparation needed for EBSD and the time

needed to complete a representative level of analysis has prevented its wider use. A number of complimentary or alternative techniques have

recently been developed and will be elucidated here. The challenges associated with effective sampling of material at relevant stages through the

process route and the methods used to quantify and compare macrozones will be discussed and demonstrated.

ABSTRACTS THURSDAY PM1 - DEFORMATION 90

Symposium D: Deformation Textures Session: Modelling

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Measured resolved shear stresses and active slip systems in austenitic steel G. Winther1, N. Ytterdal Juul1 and J. Oddershede2 1Department of Mechanical Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark. 2Xnovo Technology ApS, Køge, Denmark.

With the purpose of determining the critically stressed slip systems

in a tensile deformed austenitic stainless steel, the full stress tensor

is measured for 150 individual bulk grains using 3DXRD microscopy

at CHESS. The measured stress states are further compared to the

theoretical Bishop-Hill states. In the elastic regime, the resolved

shear stresses exhibit quite large variations between grains of

similar orientation. On average, however, the resolved shear

stresses agree well with the Schmid factors for uniaxial tension. In

the plastic regime at 1% elongation, about half of the grains were

close to a Bishop-Hill state. The orientation dependence of the

Bishop-Hill state was, however, not exactly as expected. The other

half of the grains was closer to the applied uniaxial stress, in

between two Bishop-Hill stress states, or in some cases none of

these. Comparison to finite-element crystal plasticity simulations

only qualitatively agree.

Comparison of measured lattice rotations of individual grains with crystal plasticity simulations N. Ytterdal Juul 1, J. Oddershede2 and G. Winther1 1Department of Mechanical Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark. 2Xnovo Technology ApS, Køge, Denmark.

The lattice rotations of more than 300 grains in a 0.7x0.7x0.5 mm3

volume of a 316 stainless steel sample deformed in tension have

been monitored by 3DXRD microscopy at CHESS to 5% elongation.

The initial grain morphologies and microstructure were also mapped

out in high spatial resolution using a near-field detector. This map

serves as the input to finite-element based crystal plasticity

simulations approximating the modelled crystallographic

neighbourhood of individual grains closely. The experimental

rotations are compared to the model results, revealing a larger

spread of the experimental data. Representative grains are selected

for detailed studies to investigate this in more detail.

Texture Development in Two-Phase Mineral Aggregates: Modeling Plastic Deformation with Finite Element Methods E. Zepeda-Alarcon1 and M. Kasemer2 1University of California Berkeley, Berkeley, USA. 2Cornell University, Ithaca, USA.

Modeling plastic deformation in two-phase polycrystalline materials

comprised of phases with pronounced strength contrast is of

interest because of their abundance in the Earth and for specific

engineering applications. Large strength contrast between phases

and single crystal anisotropy is known to influence the development

of stress and strain heterogeneity within grains. Texture

development in these systems has a strong dependence on the

orientation distribution, and the development of misorientation

within each grain is dependent on their orientations and the

strengths of grains within the local grain neighborhood. The classical

Taylor theory and the more sophisticated self-consistent models are

successful in modeling average properties, but do not accurately

predict intragranular heterogeneity, and typically lead to more

pronounced textures than those which are experimentally observed.

In this study, the deformation response of a two-phase polycrystal

with a mixture of orthorhombic bridgmanite MgSiO3 and cubic

periclase (MgO) is simulated by means of a crystal plasticity finite

element framework. This material is significant because it composes

most of the Earths’ mantle and is important for understanding

geodynamic processes. Special attention is drawn to the evolution of

intragranular misorientation, and its dependence on the grain

neighborhood and strength contrast between the phases. It is found

that when the bridgmanite phase is 8 times harder than periclase,

periclase carries almost 70\% of the total plastic deformation of the

aggregate, and intragranular misorientation is larger in periclase

than in bridgmanite. Furthermore, interconnected soft grains exhibit

larger deformation rates and intragranular misorientations than soft

grains surrounded by predominantly hard grains. The opposite trend

is witnessed when inspecting the hard bridgmanite phase. The

development of this intragranular misorientation is responsible for

the weak texture development that has been experimentally

observed in this two-phase aggregate with a large strength contrast.

Statistical models for deformation texture prediction using vortex-type accommodation of local strain misfits P. Van Houtte1, B. Van Bael1 Q. Xie2 and M. Seefeldt1 1Department of Materials Engineering, KULeuven, Leuven, Belgium. 2 Oak Ridge National Lab, USA.

Many advanced models for deformation texture prediction make

use of crystal plasticity finite element or fast Fourier methods. They

manage to deal with strain heterogeneities at very small length

scales occurring for example in multiphase or nanostructured

materials. However, they demand a lot of calculation power, too

much for daily use as tools for computer aided

design/manufacturing of forming operations of massively produced

steel or aluminum sheet parts. So-called statistical models for

deformation texture and plastic anisotropy are still of interest in

such cases, as they are fast and can indeed be incorporated as

constitutive models in finite element simulations of metal forming

processes. Well known statistical models which are reasonably

accurate are the VPSC and ALAMEL model. The present work

ABSTRACTS THURSDAY PM1 - DEFORMATION 91

discusses an attempt to further improve the quality of the

predictions of the ALAMEL model by not only allowing local

deviations from homogeneous strain (as ALAMEL does), but also

taking the plastic accommodation of these misfits into account. This

is not done using an Eshelby-type approach but rather by assuming

the existence of local ‘vortices’ as those observed in flowing water.

The model will be briefly explained. Predicted ODFs of rolling

textures of one steel and one aluminum alloy will be compared with

those of older models as well as with experimental results.

[1] P. Van Houtte, S. Li, M. Seefeldt & L. Delannay (2005) Int. J. Plasticty 21, 589.

[2] Q. Xie, A. Van Bael, J. Sidor, J. Moerman, P. Van Houtte (2014) Acta Materialia, 69 175.

ABSTRACTS THURSDAY PM1 – DEFORMATION 92

Symposium D: Deformation Textures Session: Torsion

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Microstructural Engineering In Pearlitic Steel Wires A. Durgaprasada, S. Giria,b, S. Lenkab, S. Kundub, S. Chandrab, S.Mishrac, R. D. Dohertya,d and I. Samajdara aDepartment of Metallurgical Engineering and Materials Science, IIT Bombay, Mumbai – 400076, India. bResearch and Development Division, TATA Steel, Jamshedpur – 831 001, India. cDepartment of Mechanical Engineering, IIT Bombay, Mumbai – 400076, India. dDepartment of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104

This study involved fully pearlitic wires of near eutectoid

composition. The original wire rod, of 5.5 mm diameter, was

subjected to seven stages of wire drawing (maximum strain of

~2.5). Microstructures and mechanical properties of both as

drawn (AD) and laboratory annealed (LA), re-austenitized and then

air-cooled to reform the pearlite structure, wires were investigated.

Morphological alignment (along the wire axis) of the LA pearlite

improved significantly (32% to 93%) as the wire diameter decreased.

This was enforced through a combination of crystallographic texture

and state of residual stress. The majority of the pearlite lamellae

appeared to align, in a 2-D analysis, with minimum elastic stiffness

(EMin under simple compression) for the ferrite (). 3-D

microstructures and measurements on coarse pearlite established

the pearlite crystallography and orientation dependence of the

pearlite growth. The LA grade offered excellent tensile strength

(from very low interlamellar spacing) and torsional ductility (from

the pearlite alignment). Absence of work hardening, on the other

hand, provided lower torsional yield than the traditional patenting-

wire drawing route.

Reciprocal effect of texture evolution and grain fragmentation during High Pressure Torsion processing S. Naghdy1, L. Kestens1,2 and P. Verleysen1 1Ghent University, Ghent, Belgium, Department of Electrical Energy, Metals, Mechanical Constructions and Systems. 2Delft University, Delft, The Netherlands, Department of materials science and engineering

The aim of this work was to examine the evolution of texture during

high pressure torsion (HPT) processing. Commercially pure

aluminum was subjected to monotonic HPT deformation at room

temperature. Microstructure and texture were studied by large area

EBSD scans. During processing, two distinct stages of microstructural

evolution were observed, a stage of grain fragmentation followed by

a saturation stage. In both stages, the global texture is characterized

by the typical shear components of face-centered cubic metals. It

was observed that a preferential fragmentation pattern occurs in

the first stage: orientations in the vicinity of ideal fibers became less

heavily fragmented while non-ideal orientations broke up more

severely. This phenomenon was linked with the lattice rotation

required to bring an initial orientation close to a stable one.

Although the texture weakened considerably during the

fragmentation stage, the texture index did not further decrease in

the saturation stage. The saturation of texture, grain refinement and

formation of microstructure are discussed in detail.

Texture gradient in extruded Mg-alloys versus extruded Mg-Al composites H.-G. Brokmeier1, S. Sanamar1, N. Chen1, X, Shi1, N. Al-Hamdany1, M. Z. Salih1, N. Schell2 1Inst. of Mat. Science and Engineering TU Clausthal, Clausthal-Zellerfeld, Germany.2Helmholtz-Zentrum Geesthacht, GEMS-Outstation DESY, Hamburg, Germany.

Crystallographic textures of bulk materials tend to have gradients for

example along cross sections of extrudates, sheets or semi-finished

products. This texture gradient can be related to the deformation

process itself, on the reduction rate per deformation pass and on

the friction conditions. Particularly, it is known from samples having

huge cross section like thick plates for ship or bridges, that strong

texture gradients exist [1]. The present investigation compares the

texture gradient of rectangular extruded Mg-alloys with Mg-Al

composites. Global texture analysis was carried out by neutrons

using the texture diffractometer TEX-2@FRG-1/Geesthacht-

Germany and texture gradients were measured by synchrotron

radiation at the high energy beamline HEMS@Petra III/Hamburg-

Germany. The global textures of Mg-alloys show typical variations of

known texture components, depending on the alloys and the

deformation process. In Mg-Al composites produced by commercial

Mg powder and commercial Al powder with mixtures of 60%Mg-

40%Al and 40%Mg and 60%Al the Mg part develops textures

components seen in Mg-rare earth alloys. Al develops the typical

deformation texture of Al. Due to the co-deformation texture

sharpness is reduced in composite material compared to pure

metals.

The texture gradients have been measured with a beam cross

section of 100 x 100 µm [2] and show strong differences for Mg-

alloys compared to Mg-Al composites. A surprising result was

obtained for the two-phased Mg - Al composite having a cross

section of 20 x 5 mm cross section. While the texture components in

Al are mostly the same over the cross section, Mg shows a quite

different behavior. In Al only the texture sharpness of the typical Al

deformation texture decreases from outside to inside, Mg losses the

plain strain texture symmetry. As already mentioned, commercial

pure Mg shows as main texture component the splitting of the

central pole in the basal pole figure (0002) in ± RD. These poles

twist, so that one pole moves to +TD and the other one to -TD with

increasing angle the closer the sample position was at the outside of

the 20mm length.

ABSTRACTS THURSDAY PM1 – DEFORMATION 93

[1] Z. Y. Zhong , H.-G. Brokmeier, E. Maawad & N. Schell (2015) IOP Conf. Ser.: Mater. Sci. Eng. 82, 012100.

[2] H.-G. Brokmeier, A. Günther, S. Yi, W. Ye, T. Lippmann & U. Garbe (2003) Adv. X-ray Analysis 46, 151.

Hierarchical data-driven models for texture evolution in advanced multiphase materials Marat I. Latypov1, Irene J. Beyerlein1, and Surya R. Kalidindi2 1University of California Santa Barbara, Santa Barbara, CA, USA. 2Georgia Institute of Technology, Atlanta, GA, USA

Modeling of engineering materials with hierarchical structure

requires multiscale approaches. Bridging across multiple length

scales in a computationally efficient fashion remains a great

challenge despite continuous improvements in the computational

power. In this talk, we will present our recent advances in the

development of an efficient data driven framework for multiscale

modeling of advanced multiphase materials. In focus will be

multiphase polycrystalline materials with consideration of

localization and homogenization problems at the length scales of

phases and polycrystalline aggregates as well as constitutive

behavior of individual crystals. Micromechanics at the phases scale

is tackled by microstructure-sensitive models calibrated to data

obtained by finite element simulations, whereas crystal plasticity

and texture evolution are addressed with the aid of an efficient

spectral database. It will be shown that the framework offers a

combination of accuracy and low computational cost and thereby

presents an important step towards fully coupled multiscale

modeling of engineering processes of advanced metallic materials

with hierarchical microstructures.

ABSTRACTS THURSDAY PM1 - TRANSFORMATIONS 94

Symposium T: Transformation Textures Symposium Chair:

Dr. Michael Roach, Biomedical Materials Science, University of Mississippi Medical Center

Formation of microtexture induced by β to α transformation in a metastable β Ti alloy Ke Hua1,2, Yudong Zhang1, Hongchao Kou2, Jinshan Li2, Weimin Gan3 and Claude Esling1 1Laboratoire d’ Etude des Microstructures et de Mecanique des Materiaux (LEM3), CNRS UMR 7239, Universite de Lorraine, 57045 Metz, France. 2State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, 710072 Xi’an, PR China.

3Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, 21502 Geesthacht, Germany.

The mechanical properties of Ti alloys are intimately related to the

microstructure produced by the β to α phase transformation during

thermal or thermo-mechanical treatments. This phase

transformation is realized by a structure change from BCC β to HCP

α accompanied by a repartition of alloying elements. Microtextures

of the α phase are often present due to the selection of α variants

and have influences on the mechanical properties of the alloy. Thus,

knowledge on the formation mechanisms is of importance. Based on

this, a study was conducted, in the present work, on the selection of

variants in a metastable β Ti alloy under stress free transformation

condition. It is found that the α phase is in plate shape and related

with the β matrix by the Burgers orientation relationship (BOR).

Locally 3 BOR α variants interrelated by a 60° rotation around the

<11-20>α form a triangular structure. Close examination revealed

that nano-sized secondary α particles precipitate in the interface

area between each α plate and the surrounding β matrix. The

orientation of the secondary α particles is the same as that of one of

the other two α plates in the triangular structure. These secondary α

particles serve as nuclei for the formation of α plates with the same

orientation in the triangular structure and contribute to the

selection of variants to form local α texture. This work provides new

insights into the formation mechanisms of the microtexture (also

transformation texture) of metastable β Ti alloys under stress free

condition.

Variant selection in alpha/beta Ti alloy D. Solas1, S. Le Corre1, R. Forestier2 and F Brisset1

1Univ Paris Sud, ICMMO, CNRS, UMR 8182, F-91405 Orsay, France. 2ARDEM; Aubert & Duval 75 boulevard de la Liberation ; B.P.173, Pamiers Cedex, 09102, France

Mechanical properties of alpha/beta Ti alloys are improved through

complex thermomechanical treatments. The effects of beta forging

on microstructure and phase transformation are investigated for a

Ti-6246 alloy. Textures have been measured by neutron and X ray

diffraction. SEM/EBSD investigations have been used to characterize

the alpha phase precipitation.

After beta-forging, the microstructure is composed of clusters of

grains with <100> or <111> direction aligned with the forging

direction. During beta to alpha transformation, alpha orientation is

determined by the Burgers orientation relationship. One beta grain

generates up to twelve alpha orientations. After high deformation in

the beta domain, only 4 variants appear in the <100> grains,

whereas no variant selection is observed in the <111> grains.

Finally, the anisotropy of elastic properties of the alpha/beta

domains is calculated using a self-consistent approach. The elastic

properties of both phases are taken into account as well as the

different configurations of alpha variant selection.

Probabilistic methodology for analyzing and reconstructing parent microstructures from EBSD maps of transformation products Stephen Niezgoda1, Eric Payton2, Alex Brust1, and Vikas Sinha2 1The Ohio State University, Columbus OH, USA. 2Air Force Research Laboraotry, Dayton OH, USA.

The properties and performance of transformation microstructures

are often dependent on features of the prior microstructure, such as

texture or grain size, which have been obscured by the

transformation. Reconstruction of the parent is typically

mathematically ill-posed, as the forward transformation

Is often one-to-many; exhibiting multiple orientation variants or

transformation pathways. Point-to-point reconstruction techniques,

which rely on a pre-supposed orientation relationship, may not be

robust to noise or deviations from ideal conditions. Here we present

a probabilistic approach to quantify

The uncertainty in the orientation relationship and noise due to

measurement resolution, variation in parent orientation, and sample

preparation. The reconstruction is formulated as a global

optimization where the target is to minimize the probability of

misindexed points or equivalently to find the parent microstructure

which was most likely to generate the observed transformed

dataset. While the approach is material agnostic and will be

demonstrated on prior-austenite grain reconstruction in carbon

steels.

Orientation dependent spheroidization response and α-phase texture evolution during sub β-transus annealing of Ti-6Al-4V alloy Shibayan Roya,b, Satyam Suwasb aMaterials Science Centre, Indian Institute of Technology, Kharagpur, India. bDepartment of Materials Engineering, Indian Institute of Science, Bangalore, India

Spheroidization response of the constituent α-colonies in a warm-

rolled Ti-6Al-4V alloy is known to differ significantly during sub β-

transus static annealing. In this communication, the same has been

examined for the first time from an orientation perspective by

coupling slip activation, boundary formation and interfacial energy

anisotropy of individual α-colonies. The orientation of the α-colonies

with reference to the loading directions dictates the nature of slip

activation (single versus multiple slip; basal or prism <a> slip plus

pyramidal <c+a> slip) during (α+β)-rolling in the first place. During

subsequent static (α+β)-annealing, this factor initially translates into

the relative ease of boundary splitting and thermal grooving for

ABSTRACTS THURSDAY PM1 - TRANSFORMATIONS 95

them. Formation of longitudinal boundaries then set the order of

spheroidization for diffusion based coarsening processes during long

term annealing. Anisotropy in interfacial energy as a consequence of

loss of coherency during prior deformation creates further

orientation dependency in the spheroidization sequence. As a

concomitant effect, sub β-transus annealing results in significant

weakening of basal fibre (ND║<0001>) and complementary

strengthening of prism fibre (RD║<10 0>) from prior-rolled texture.

This modification is conjugated to the orientation dependent

spheroidization of primary α-phase (αp) which makes a distinction

between their relative contribution to these texture fibres.

Orientations proximity between secondary α (αs) and stable αp-

phases further contributes to this texture transition.

ABSTRACTS THURSDAY PM1 - ENGINEERING 96

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Processing – Friction Stir Welding

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Texture evolution in flash and weld zone of friction welded 718 superalloy T.W. Nelson, F.C. Liu, and, C. Brown Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602, USA

During rotary friction welding, the friction and plastic deformation

causes softening in the two pieces near the weld interface. As the

material softens, material is gradually extruded or expelled away

from the interface under an axial force, forming flashes. Texture

analysis of the flash and weld zone of friction welded 718 superalloy

is beneficial to the understanding of the deformation and material

flow during welding. The texture was firstly measured on a post-

welded sample which is produced through a standard welding

procedure. The B component {112}<110> was detected in the weld

zone. The deformation texture was concealed in the flash as a result

of significant grain coarsening. In order to investigate the grain

structure, material flow and texture evolution during deformation, a

water quench was applied during the welding. In the quenched

samples, stronger B component {112}<110> was detected in both

the flash and weld zone. The shear direction of the B component can

be used an indicator of the local material flow direction.

Using EBSD in the characterization of heterogeneous microstructure created in high speed friction stir welded aluminum alloy Jingyi Zhang1, Cory Palmieri1, Piyush Upadhyay2, Yuri Hovanski3, and David P. Field1 1Washington State University, Pullman, USA. 2Pacific Northwest National Laboratory, Richland, USA. 3Brigham Young University, Provo, USA.

EBSD provides valuable information about the deformation history

of materials. The input data of EBSD are collected on a

microstructure level, making it the ideal approach for analysis of

materials with large spatial texture gradient such as friction stir

welded (FSW) structures. In this study we explore the various

possibilities and benefits of using EBSD technique and texture

analysis to characterize the formation and properties of aluminum

high-speed friction stir welds. The deformation texture present in

the weld structure is calculated on microstructure scale and used to

determine the local deformation mode and deformation direction.

This approach can generate the material flow field inside the nugget

zone and TMAZ of FSW, and help to determine the stress state in the

fusion zone underneath the nugget zone. Other characterizations

including the grain boundary misorientation distribution and GNDs

density are also made from EBSD data to describe the wide variety

of microstructure across the weld affected volume.

Friction Stir Weld Textures and their Implications on 3D Material Flow R.W. Fonda, K.E. Knipling and D.J. Rowenhorst U.S. Naval Research Laboratory, Washington, DC, USA.

The deformation textures produced by friction stir welding can be

used to reveal the three-dimensional material flow that was

occurring during welding. Friction stir welding generates

deformation textures that vary in orientation in a complex manner

across the width and through the thickness of the deposited weld.

These orientation variations correspond to changes in the local

shear deformation frame of reference at the time of deposition, and

can be approximated geometrically using the fractional distance

across the weld and the effective tool surface inclination at that

depth [1]. Experimentally observed friction stir weld textures

generally follow these predictions, but also exhibit deviations that

signify variations from the expected local shear deformation

orientation, and thus local variations in the material flow direction.

These deviations have been quantified across the weld at three

depths to reveal the three-dimensional material flow that occurs

during friction stir welding.

[1] R.W. Fonda, K.E. Knipling, & D.J. Rowenhorst (2014) JOM 66, 149.

Texture evolution during friction stir welding of austenite stainless steel F.C. Liu, and T.W. Nelson, M.P. Miles Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602, USA

The texture evolution during the whole process of friction stir

welding (FSW) of 304L stainless steel are clarified. As the base

material approached the probe, grains were compressed, evolving

to fine equiaxed grains mainly through discontinue dynamic

recrystallization (DDRX). As these fine grains rotated around the

probe, The B component {112}<110> with its shear direction being

consisted with the local probe rotation was developed. The shear

plan of B component maintained approximately 30 deg away from

the probe profile. After the material was deposited behind the

probe, deformation caused by tool shoulder weakened the B

component. The B component evolved to a C component

{001}<110> in the region whose deformation was significantly affect

by the shoulder. For the samples welded at reduced welding power,

the texture was less effected by the shoulder and the B component

{112}<110> was remained in the weld zone.

ABSTRACTS THURSDAY PM1 - BOUNDARIES 97

Symposium B: Misorientation Textures at Grain Boundaries and Interfaces Symposium Chairs:

Dr. Eric Homer, Department of Mechanical Engineering, Brigham Young University

Dr. Srikanth Patala, Department of Materials Science and Engineering, North Carolina State University

Role of CSL Boundaries During Cold Rolling and Annealing of an Interstitial Free Steel Rajib Saha1, R. K. Ray2 and A. D. Rollett3 1Research & Development Division, Tata Steel, Jamshedpur, India. 2MN Dastur School of Materials Science and Engineering, IIEST, Kolkata, India. 3Materials Science & Engineering, Carnegie Mellon University (CMU) USA

Changes in the texture and CSL boundary distribution during cold

rolling and annealing of a commercial grade Interstitial Free (IF) steel

have been investigated. The CSL boundaries associated with

particular texture types were quantified using the OIM™ Texture

Analysis software. This was done for both individual components of

texture, as well as for groups of components belonging to the γ

(ND//<111>) and the α (RD//<110>) fibers. The total lengths as well

as number fractions of various CSL boundaries related to different

texture types were then determined. The results clearly show that

each particular type of texture (individual component or a group of

components) is associated with a particular CSL grain boundary

distribution (CGBD). The histograms of CSL number fraction and

length fraction as a function of CSL type are similar in shape. The

density of Σ3 boundaries is the highest amongst all the CSL

boundaries for all the textural conditions. In general, the total CSL

fraction increases from the cold worked to the recrystallization

state, although the total CSL fraction decreases during grain growth.

Generally, the number fraction of CSL boundaries is higher in case of

the 110//RD texture grains as compared to the 111//ND oriented

grains. During grain growth, however, the 111//ND related CSL

boundaries increase at the expense of the 110//RD related CSL

fraction. An attempt has been made to explain the above

observations with the help of texture and microstructure data.

The Representation of Grain Boundary Texture Using Hyperspherical Harmonics Srikanth Patala1, Jeremy K. Mason2 1North Carolina State University, Raleigh, USA. 2University of California, Davis, USA.

The statistical distribution of different grain boundary types play an

important role in governing the mechanical and function properties

of polycrystalline materials. However, even for simple

microstructures, the capability of representing the distributions of

GB character, as a function of the five macroscopic degrees of

freedom, has not been established. As the GB character distributions

directly influence the interfacial network connectivity, developing a

framework for quantifying the statistics in the five-parameter space

is a crucial missing step in the inverse-design of interface-dominated

phenomena in polycrystalline systems. In this talk, I will present

symmetrized functions, using the familiar hyperspherical harmonics,

for representing grain boundary texture in the complete five-

parameter space. The basis functions will also allow for the

quantification of interfacial statistics in experimental

microstructures and the interpolation of structure-property

relationships of grain boundaries.

Grain orientation statistics of grain-clusters and the propensity of multiple-twinning during grain boundary engineering Shuang Xia, Tingguang Liu, Qin Bai, and Bangxin Zhou School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China

Large grain-cluster or so-called twin-related domain is a typical

characteristic of the grain boundary (GB) engineered microstructure.

Grain-cluster is formed via numerous twinning operations starting

from single nucleus, and the process is referred to as multiple-

twinning. This work investigated the orientation diversity within

grain-clusters and the twinning ordering of multiple-twinning based

on the statistics of grain-orientations in 30 large-sized grain-clusters

from GB-engineered Ni-based alloy 690. The statistics show that the

grain-cluster apparently has several dominant orientations. A few

dominant orientations occupy most area and most grains in a grain-

cluster. Moreover, most misorientations between these dominant

orientations are of low-order ∑3n-type (n=1, 2), and the 4 sub-

dominant orientations are twinning variants of the first-dominant

orientation in most cases. These statistical characteristics of grain-

clusters reflect the general behavior of multiple-twinning: back-and-

forth pattern and preferential orientations. The twinning operations

produce not only higher (forward) but also lower (backward)

generation orientations, and the backward probability is higher than

the forward. The multiple-twinning shows a propensity to form or

access to a few preferential orientations, and results in the

formation of dominant orientations of the formed grain-cluster.

[1] T.G. Liu, S. Xia, B.S. Wang, Q. Bai, B.X. Zhou & C. Su, (2016) Mater. Des. 112, 442

ABSTRACTS THURSDAY PM2 - DEFORMATION 98

Symposium D: Deformation Textures Session: Modelling

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Revealing deformation heterogeneity from texture modeling Laszlo S. Toth Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures (DAMAS), Université de Lorraine, Metz, France, Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux (LEM3), UMR7239, CNRS / Université de Lorraine, F-57045 Metz, France

It is well known in experiments and also in modeling that

crystallographic texture is very sensitive to the mechanisms acting

during its formation. It is therefore suitable to examine all

phenomena that can change the crystallographic orientation

(dislocation slip, twinning, grain boundary sliding, recrystallization,

phase changes, etc…). Moreover, the texture being three

dimensional, it is not an easy task to reproduce it by modeling.

Therefore, successful simulations can provide strong evidences for

the existence of the mechanisms and for their magnitudes.

The present work aims to reveal the deformation inhomogeneities

that can exist between neighboring grains of the polycrystal. The

work reports about experiments as well as simulations in various

deformation paths and on different materials concerning the

evolution of the crystallographic texture and the density of

geometrically necessary dislocations (GNDs). The viscoplastic self-

consistent model was employed for reproducing the texture

evolutions. The major findings are:

1. In large and medium grain sized polycrystals the

deformation can be very heterogeneous, while grains of a

polycrystal composed of nano-sized grains deform very

similarly (Taylor-mode).

2. The GND density is a signature of strain heterogeneity and

the experiments confirm the above finding for the

deformation tending towards Taylor as the grain size

decreases.

3. Partial slip becomes a relevant deformation mechanism as

grain size decreases.

Acknowledgments

This research work was carried out in collaboration involving: Prof.

Werner Skrotzki, Technical University, Germany, Dresden, Dr.

Chengfan Gu, RMIT University, Melbourne, Prof. Tamas Ungar,

Eotvos University, Hungary, Prof. Irene Beyerlein, University of

California, Santa Barbara, Prof. Mark Hoffman, UNSW, Sydney,

Australia, Dr. Arnaud Pougis, SNECMA, Paris, France, Dr. Benoit

Beausir – Dr. Jean-Jacques Fundenberger – Dr. Yudong Zhang –

Lorraine University, Metz, France.

This work was supported by the French State through the program

"Investment in the future" operated by the National Research

Agency (ANR) and referenced by ANR-11-LABX-0008-01 (LabEx

DAMAS).

Texture evolution in Al alloys: crystal plasticity and continuum mechanics based modelling strategies Jurij Sidor Savaria Institute of Technology, Eötvös Loránd University (ELTE), Károlyi Gáspár tér 4, 9700 Szombathely, Hungary

Material’s flow during deformation is discussed by means of well-

established crystal plasticity (CP) approaches and principles of

continuum mechanics. Investigation of material’s behavior by finite

element models (FEM) excludes the mesoscopic transformation

which accounts for evolution of microstructure with characteristic

texture. Contrarily, Taylor-type crystal plasticity homogenization

models, dealing with partitioning of macroscopic load in a

polycrystalline aggregate, are not capable of explaining the effect of

various technological parameters on deformation flow. This

contribution provides a brief overview on modelling the

deformation textures by combining both CP and FEM approaches

and also discusses the effective strategies employed in texture

simulations. The effect of grain interaction phenomena on the

quality of texture prediction is revealed. With the help of CP and

FEM simulations, it is shown how microstructural heterogeneities

might influence the evolution of recrystallization and plastic strain

ratio in aluminum alloys.

Crystal plasticity simulations of rolling texture evolution in two phase tungsten heavy alloy Mirtunjay Kumar, N. P. Gurao, Anish Upadhyaya Indian Institute of Technology Kanpur, Kanpur, India

Evolution of texture and microstructure during rolling of two phase

tungsten heavy alloy (WHA) was investigated using bulk texture

measurement, electron backscatter diffraction and X-ray line profile

analysis. The experimental results showed the presence of

characteristic alpha <110> rolling direction and gamma fibre {111}

parallel to the ND plane in the 90% rolled WHA sample with the

gamma fibre being stronger than the alpha fibre. Evolution of

misorientation and orientation gradients in the body centre cubic

tungsten and face centre cubic Fe-Ni-W solid solution phase

indicated strain partitioning between the hard tungsten and soft Fe-

Ni matrix. Different crystal plasticity models like the in-house

developed full and relaxed constraint Taylor model and LAMEL and

ALAMEL model, grain interaction model as well as existing

viscoplastic self-consistent and crystal plasticity finite element

model. A comparison of the experimental texture with the simulated

texture obtained from different models will be presented with a

detailed discussion on the advantages and disadvantages of

different models. A perspective on the suitability of different models

ABSTRACTS THURSDAY PM2 - DEFORMATION 99

for predicting the evolution of deformation texture in WHAs will be

presented.

Intergranular interactions of metals during deformation and corresponding prediction of deformation textures W. Mao1,2 1Inner Mongolia University of Science and Technology, Baotou, China. 2University of Science and Technology Beijing, Beijing, China.

Most current theories and models for plastic deformation of

polycrystalline metals are based on the Taylor principles and some

modifications whereas the strain equilibrium between deformation

grains are reached obviously. However, the issue on stress

equilibrium has not been satisfactorily resolved yet. Therefore, the

deformation behaviors described by the theories are more or less

different from those of the grains in polycrystalline metals. The very

simple reaction stress model proposed emphasizes mechanical

interactions between grains, and both of the stress and strain

equilibria are obtained by activations of penetrating and non-

penetrating slips. The rolling texture simulations under the model

predict the same textures indicated by Taylor theory both in bcc and

fcc metals.

It is indicated that reaction stresses calculated between grains could

not be fully effective on evolution of grain orientations during rolling

of aluminum alloys and need to be relaxed, whereas brass texture

will be predicted by a fully relaxation of the reaction stresses.

Different reaction shear stresses may reduce brass texture and

promote S, Taylor texture or even copper texture instead of Taylor

texture. The β-fiber by high rolling reduction is located in the

orientation area, where the Schmid factors of activated slip systems

are sufficiently high and the brass shear strain is kept relatively low.

Different detailed engineering conditions have to be included in

deformation simulations if the deformation textures of industrial

products need to be predicted. The introduced reaction stress

principles, based on solid mechanical background, open theoretically

a new field of vision to consider deformation behaviors of

polycrystalline materials. Consequently, the Taylor principles

become no longer absolutely necessary.

ABSTRACTS THURSDAY PM2 – DEFORMATION 100

Symposium D: Deformation Textures Session: Damage and Fracture

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Mechanical damage evaluation by using EBSD measurement Seiichi SUZUKI1, Masayuki KAMAYA2, Keiji KUBUSHIRO3 and Toshihiro OHTANI4 1TSL Solutions KK, Sagamihara, Kanagawa, Japan. 2Institute of Nuclear Safety System, Inc.64 Sata, Mihama-cho, Fukui 919-1205, Japan. 3IHI Corporation, 1, Shin-nakahara-cho, Isogo-ku, Yokohama 235-8501, Japan. 4Shonan Institute of Technology, 1-1-25, Tsujidonishikaigan, Fujisawa-shi, Kanagawa 251-8511, Japan

Estimation of the remaining life time of turbine blade used under

high temperature environment is very important in industries.

Major cause to degrade these mechanical parts, which is expressed

as mechanical damage, are creep deformation. If the remaining life

time of these mechanical parts can be assessed by observing their

micro structure changes, it will offer big advantages for maintenance

of the systems using these parts. This research work was

performed to find some good method to evaluate the mechanical

damage by observing microstructure changes during creep

deformation.

8 tensile rod specimens of SUS316 were prepared. Creep test had

been done by using these specimen under the temperature of

700deg. C with 100MPa load. Creep test were continued for 0.0,

268, 489, 507, 528, 562, 584 and 694 hours, and resulted in tensile

elongation of 0.0, 7.37, 14.2, 21.6, 24.9, 18.4, 28.0 and 44.6%

respectively. The specimens were cut along with the center axis

which is same as tensile direction and polished for EBSD

observation. EBSD observation was done at continuous 3 areas with

scan size of 200x200m and step size 0.5m, then they were

merged into one date of 580x190 m.

It was observed that (111) plane normal direction became aligned

with tensile direction along with increase of deformation.

Misorientation maps such as KAM (Kernel Average Orientation) and

GOS (Grain Orientation Spread) were examined and the values of

both parameters increased as increase of deformation. But KAM

maps depended seriously on the step size and it was found that GOS

showed much more stable results of almost proportional relation to

the level of deformation. It was also found that the boundaries’

characters were changed along with the deformation. The original

SUS316 specimen had a lot of twin boundaries. But these twin

boundaries were decreased and low angle boundaries of less than 5

degrees increased very much during deformation. The ratio of twin

boundary against low angle boundaries were observed to decrease

well proportional to the level of the deformation. The decrease of

twin boundary was mainly caused by deviating from the condition of

plane matching of K1 planes [(111) planes of both side of the twin

boundary should be parallel] which tolerance was set to 1degree.

So the ratio of twin boundaries with K1 plans matched and without

K1 planes matched decreased well proportional to the degrees of

deformation up to around 15%.

As results of this series of experiments, it can be possible to estimate

the remaining life time of high temperature material by observing its

microstructure changes such as KAM, GOS and twin boundary

characters. Further test may be necessary to confirm these results

for industrial application.

This work was originally done as a basic research experiment of

‘Mechanical Damage Assessment WG’ under the High Temperature

Material Committee of the Society of Materials Science of Japan. [1]

[1] M. Kamaya, et.al (2016) Mechanical Engineering Journal, Vol3, No3

Damage initiation mechanisms under static and dynamic loading conditions in bainitic steels B. Shakerifard1, J.G. Lopez2 and L.A.I. Kestens3 1,3Technical University of Delft, Delft, Netherlands. 2Materials Innovation Institute, Delft, Netherlands.

The goal of this research is to optimize the microstructure of a

bainitic advanced high-strength steel in order to improve cold

formability and edge-cracking behavior. This will enable enhanced

energy absorption due to higher yield strength, higher elongation

and favorable crash folding behavior because of improved bending

properties. To approach this goal, two batches of bainitic steel with

low and high silicon contents were produced. Several annealing

treatments were carried out to provide a bainitic matrix with various

morphologies of second phase constituents (martensite, retained

austenite and carbides). Static and dynamic mechanical tests were

performed in order to evaluate the mechanical response of the

materials to the low and high strain rate deformations, respectively.

The microstructures and their textures were analyzed quantitatively

by X-ray diffraction and orientation contrast microscopy. The

correlation between microstructural features and mechanical

properties has been studied. In addition, the damage initiation

mechanism under static and dynamic loading conditions were

studied and compared.

Evaluating the Role of Texture on Surface Roughness Induced Stress Concentrations C. A. Kantzos1, R. W. Cunningham1, and A. D. Rollett1 1Carnegie Mellon University, Pittsburgh, USA.

Stress concentrations caused by geometric inhomogeneities on the

surface of a material are well known to have a negative impact on

mechanical performance, especially by promoting fatigue crack

initiation. Some empirical and mechanical models have been

developed to relate surface geometry to mechanical properties, but

very little has been done to incorporate microstructural texture,

especially local surface texture, into such models. Herein an FFT-

ABSTRACTS THURSDAY PM2 – DEFORMATION 101

based crystal plasticity model is used to evaluate how texture,

coupled with surface roughness, can increase stress concentrations

and localized slip activity. Based on experimental observations,

simulated 3D surfaces with varying degrees of texture were

generated, and the response to different loading conditions were

analyzed using extreme value statistics. The relevance of these

results to fatigue life, and the importance of texture considerations

are discussed.

EBSD Observations of Fatigue Crack Propagation in Ni Alloy S. I. Wright1, M. M. Nowell1, R. de Kloe2 1EDAX, Draper, UT, USA. 2EDAX, Tilburg, The Netherlands

Electron Backscatter Diffraction (EBSD) observations were made on

a Ni alloy containing a fatigue crack. The crack was observed to be

both transgranular and intergranular. From the EBSD observations

on the two-dimensional plane it was found that the crack

propagated primarily following (111) plane traces. Analysis of the

plane traces was conducted to try and gain some understanding of

the local dynamics governing the propagation of the crack through

the microstructure.

ABSTRACTS THURSDAY PM2 - NUMERICS 102

Symposium N: Mathematical, Numerical and Statistical Methods of Texture Analysis Symposium Chair:

Dr. Oliver Johnson, Department of Mechanical Engineering, Brigham Young University

Parameterization of rotations in reference frames with redundant crystallographic axes A. Morawiec Polish Academy of Sciences, Institute of Metallurgy and Materials Science, Reymonta 25, 30-059, Krakow, Poland,

Parameterizations of orientations or rotations in three-dimensional

space are fundamental for description of crystallographic textures.

Such parameterizations (e.g., Rodrigues parameters) are usually

specified using orthonormal coordinate systems, whereas bases of

crystal lattices are generally non-orthogonal. In the case of crystals

with hexagonal or rhombohedral lattices, the reference frames

involve redundant crystallographic axes. Hence, a question arises

about feasibility of the generalization of the rotation

parameterizations to such frames. We will present a method of

extending the definition of Rodrigues parameters so they can be

directly linked to non-Cartesian bases of crystals. The new Rodrigues

parameters are contra- or covariant components of vectors specified

with respect to exactly the same lattice basis as atomic positions in a

unit cell. The generalized formalism allows for using redundant

crystallographic axes. Also, the orientation matrices can be

represented in such frames. The formulas for rotation composition

and the relationship between the rotation matrices and Rodrigues

parameters are similar to those in the Cartesian case, but they more

general: calculations can be performed with an arbitrary metric

tensor of the crystal lattice. The Rodrigues parameterization in non-

Cartesian coordinate frames is convenient for crystallographic

applications because the generalized parameters are directly related

to indices of rotation-invariant lattice directions and to Miller indices

of rotation-invariant lattice planes. In the case of in the hexagonal

and rhombohedral lattices, the redundant axes are used to account

for lattice symmetry, but one may use such axes for other reasons;

they can be useful for handling arbitrary symmetries, in particular,

symmetries of physical processes. E.g., in description of orientation

changes during plastic deformation, the frames can be chosen based

on characteristic directions and/or planes of slip or twinning

systems.

Systematic bias effects on phase fraction measurement due to texture A. Creuziger, C. Calhoun, W. Poling and T. Gnäupel-Herold National Institute of Standards and Technology, Gaithersburg, MD USA

Most advanced high strength steel alloys contain multiple phases,

each of which can have its own crystallographic texture. Accurate

measurement of the phase fractions via diffraction techniques

remains a challenge for many reasons. In particular, accounting for

texture remains elusive in current standards and practices. Many

methods have been proposed to deal with texture, such as use of

multiple peaks and/or additional tilt and rotation. However, a

systematic examination of these methods for bias errors due to

texture remains outstanding.

The present study serves as a first step in assessing the accuracy of

various proposed diffraction techniques through numerical

investigation of texture effects on simulated diffraction

measurements. The authors explored a two-phase system with fixed

phase fractions of 0.25 austenite and 0.75 ferrite. Synthetic textures

were computed, and for each generated texture, diffraction

intensities were computed for different diffraction methods. It was

seen that no methods had significant bias in the phase fraction value

for a random texture, but as texture increased, bias errors increased.

For a single sample orientation, using two austenite and two ferrite

peak pairs, calculated phase fractions of austenite ranged from 0.08

to 0.68 for a sample generated using a phase fraction of 0.25.

Increasing the number of considered peaks decreased the spread,

but apparent phase fractions still ranged from 0.18 to 0.35.

Simultaneous tilt and rotation yielded a comparable range of values.

However, if a hexagonal grid of pole figure space was used,

drastically lower bias errors were observed.

Comparison of Representative Volume Elements for Grain Boundary Networks and Textures T.R. Critchfield1, O.K. Johnson Brigham Young University, Provo, USA.

The use of representative volume elements in simulation of

polycrystalline microstructures facilitates a balance between

accuracy and computational efficiency. A representative volume

element (RVE) is the smallest sample size that accurately represents

the microstructure, in the context of the material property being

observed. The required size of an RVE has been determined for

texture-sensitive properties, but these findings have not addressed

the influence of the grain boundary network. We present findings on

appropriate RVEs for grain boundary networks in a diverse set of

microstructures and compare these to the required RVE for texture

in the same microstructures. These results will allow researchers to

accurately simulate and model grain boundary networks in a

computationally efficient manner and offer further insight to the

underlying influence of short- and long-range correlations on RVE

size.

Quantification of Uncertainties in Pole Figure Analysis S.K. Sridhar and A.D. Rollett Carnegie Mellon Univ., Pittsburgh, USA.

The effects of texture on Superelastic Effect (SE) and Shape Memory

Effect (SME) of Nickel Titanium (NiTi) have been extensively studied.

The experimental techniques to measure texture usually include

diffraction techniques like X-ray and neutron diffraction or

Orientation Image Mapping (OIM) techniques such as Electron Back

Scatter Diffraction (EBSD). However, EBSD is a surface based

technique and sample preparation is very demanding. EBSD is

challenging for NiTi samples because of their sensitivity to

mechanical surface deformation, especially when they are already

heavily cold worked. Therefore, the best method to get texture data

is using diffraction techniques. However, since lab diffraction

ABSTRACTS THURSDAY PM2 - NUMERICS 103

techniques such as X-ray Diffraction (XRD) typically measure

incomplete pole figures, it is essential to correct for this using

mathematical methods and estimate numerically the Orientation

Distribution Function (ODF). Moreover, there exist several ways to

estimate ODF from raw experimental Pole Figures (PFs). This further

leads to uncertainties in the interpretation of texture especially

when robust estimates of the volume fractions of the various

texture components are needed. This work organizes the calculation

of ODFs and quantification of uncertainties that arise depending on

the method chosen. The overall aim is to improve standards for

comparing texture among different samples.

ABSTRACTS THURSDAY PM2 - ENGINEERING 104

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Processing – Asymmetric Rolling

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Experimental and Numeric Analysis of Strain and Texture of Asymmetric Rolled AA1050 Aluminum B. D. Zanchetta1, F. S. Nascimento2, A. M. Kliauga2, J. B. Rupert3, R. E. Bolmaro 4 1Universidade Federal de São Carlos, CCTS, Sorocaba, Brazil. 2Universidade Federal de São Carlos, Department of Materials Engineering, São Carlos, Brazil. 3Universidade Federal de São Carlos, Department of Mechanical Engineering, São Carlos, Brazil. 4Instutituto de Fisica de Rosario,Universidade Nacional de Rosario, Rosario, Argentina.

The asymmetrical rolling (AR) increases the shear strain during

deformation by changing the speed ratio between the superior the

inferior rolls. This will modify the texture of the deformed material

and induce greater grain refinement [1]. It also modifies the

recrystallization textures and thus alter the plastic anisotropy of

rolling sheets [2]. In this work, we quantified the equivalent

deformation and the induced percentage of shear of a AA1050

aluminum at speed ratios of 1.5 and 2.0 and thickness reduction per

pass of 10% and 5% up to an equivalent deformation of 1.4. The

experimental results were compared with the numerical simulation

using DEFORM V10. The crystallographic orientation was measured

by x-ray diffraction at the samples middle plane after each pass. The

initial sample had a recrystallization texture with a clear cube

texture. The distribution of shear, compression and rigid body

rotation was obtained from the finite element simulation. Most of

the shear components were concentrated at the sub surface planes,

closer to the rolls; and, at the samples middle plane the rigid body

rotation was the predominant strain component. A clear difference

in texture between surface and center was measured at an

equivalent deformation of 1.0. Consequently, the measured texture

for the initial rolling passes showed only a progressive rotation of

the texture components, whereas the subsurface region presented

shear components. Only after the final reduction steps shear

components could be identified at the middle plane. Increasing the

tangential speed ratio yielded higher shear strains but the effect of

reducing the reduction step was much more pronounced.

[1] G. Angella, B. EsfandiarJahromi, M. Vedani, (2013) Mat. Sci. Eng. A 559, 742.

[2] S. Tamimi, J.P. Correia, A.B. Lopes, S. Ahzi, F. Barlat, J.J. Gracio (2014) Mat. Sci. Eng. A 603, 150.

Texture and microstructure development in warm asymmetric rolled extra low carbon steel Satyaveer S Dhinwal and Peter D Hodgson Institute for Frontier Materials (IFM), Deakin University, Geelong, Australia

It has been noted that the metal processing based on shear

deformation exhibits enhanced grain refinement. Such metal

processing methods are also an alternate to tailor the deformation

texture of extruded bars and flat rolled sheets for some of their

structural and functional applications. Among them, rolling with

imposed asymmetric condition has been considered comparatively

more viable option to introduce through thickness shear effect in

continuous sheet manufacturing. It is because of the easy

implementation in conventional rolling mill and its ability to rotate

conventional rolling texture up to the preferred location of ideal

shear texture in Euler space.

The effect of asymmetric condition in warm rolling and its

consequences on recrystallization behavior is less investigated topic

as compared to the rolling in ambient condition. In the present

study, extra low carbon steel was warm rolled in between 250°C and

700°C and asymmetric conditions were imposed by changing roll

diameters ratio from 1:1 to 1:2 while having thickness reductions

per pass (TRPP) of 50% and 75%. It was observed that at lower warm

temperatures, the mid thickness regime of longitudinal

(perpendicular to the transverse direction) plane of a rolled sheet

shows rise in the fraction of orientation splitting and band formation

as the roll diameters ratio increases for a given TRPP. However, in

higher warm temperatures, the rate by which recrystallizing grain

forms in the vicinity of original grain bands and increase in their

fraction become significant in same asymmetric conditions of the

rolling.

Microstructural analysis with increase in the roll diameters ratio

reveals that Goss {110}<001> and D {112}<11-2> orientations of

shear texture are in strong majority as compared to any other

preferred orientations of a symmetric (1:1) case for a given area

fraction in the mid thickness of a rolled sheet. While, examination of

the grains which recrystallized during rolling shows the dominance

of Goss and D orientations along with noticeable presence of α fiber

<110> orientations of symmetric rolling.

It has been concluded from the present study that the mid thickness

regime of a rolled sheet can also form preferred orientations of

shear texture in majority as compared to the conventional rolling

texture. Formation of such shear texture orientations in warm

asymmetric rolled condition also affects the magnetization behavior

of thin laminates.

Modification of Texture and Microstructure of Polycrystalline Copper after Asymmetric Rolling A. Uniwersał1, M. Wróbel1, K. Wierzbanowski2, M. Wroński2, S. Wroński2, I. Kalemba-Rec1, T. Sak3 and B. Bacroix4 1AGH University of Science and Technology, Faculty of Metals Engineering and Industrial Computer Science, 30-059 Kraków, Poland. 2AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, 30-059 Kraków, Poland. 3AGH University of Science and Technology, Faculty of Non-Ferrous Metals, 30-059 Kraków, Poland. 4LSPM-CNRS Université Paris 13, 93 430 Villetaneuse, France

ABSTRACTS THURSDAY PM2 - ENGINEERING 105

Asymmetric rolling process is a subject of many research works in

the last years. In this kind of rolling some technological parameters

can be modified, like: normal forces and torques, sample shape (by

bending) and power requirements. The material properties are also

noticeably modified. An important shear deformation, characteristic

for this process, leads to texture rotation, microstructure refinement

and increase of material strength. Asymmetric rolling can be realized

by a modification of existing rolling mills; therefore, its industrial

application is possible at a relatively low cost.

The aim of the present study was to characterize this process and

resulting material modifications in the case of the polycrystalline

technically pure copper. The cases of low and high deformations

were examined. The EBSD, XRD, calorimetry and microhardness

measurements were performed. Texture and mechanical

characteristics were studied using a crystal deformation model and

FEM. The following material and process modifications were found

as a result of asymmetric rolling:

- sample bending, which can be partly controlled,

- decrease of mill load and an increase of the average rolling

torque,

- increase of microhardness,

- increase of energy released during recrystallization,

- distinct texture rotation around transverse direction,

- decrease of the average grains size (persisting in some

extent also after recrystallization) and formation of more

fragmented grains,

- modification of misorientation distributions.

ABSTRACTS THURSDAY PM2 - BOUNDARIES 106

Symposium B: Misorientation Textures at Grain Boundaries and Interfaces Symposium Chairs:

Dr. Eric Homer, Department of Mechanical Engineering, Brigham Young University

Dr. Srikanth Patala, Department of Materials Science and Engineering, North Carolina State University

Excess Dislocation Density near Boundaries as a Function of GB Texture D.P. Field Washington State University, Pullman, WA, USA.

Dislocation interactions with GBs have been discussed in the

literature on various levels with most focus being on the interaction

of individual dislocations with grain boundaries. Boundaries can be

barriers, sources, or sinks for dislocations. Excess dislocations

develop at many grain boundaries in a polycrystalline metal, but at

the same time, many grain boundaries are free of such dislocation

content. This study investigates excess dislocation content near

grain boundaries as a function of boundary character in lightly

deformed copper and IF steel.

Characterizing GB Dislocation Interactions though HR-EBSD and Machine Learning L.T. Hansen1, H.J. Bong2, J.D. Carroll3, D.T. Fullwood1, E.R. Homer1, and R.H. Wagoner2 1Brigham Young University, Provo, UT, USA. 2Ohio State University, Columbus, OH, USA. 3Sandia Nation Laboratories, Albuquerque, NM, USA.

The purpose of this research is to better understand the how

dislocations interact with GBs and specifically what GB

characteristics have the greatest effect on dislocation pileup. GBs in

strained polycrystalline tensile samples were characterized using

EBSD and optical microscopy. Geometrically necessary dislocation

(GND) build up at GBs was identified and quantified using high

resolution EBSD (HR-EBSD) in conjunction with a custom built

MATLAB routine. All GB information and GND build up information

was analyzed using machine learning; several preexisting theories

were validated and various trends identified. By using machine

learning on a large number of GBs, insights can be made which

would not otherwise be possible through human observation.

Study of Grain Boundary Character distribution in Annealed and Deformed Aluminum by 3D EBSD H. Pirgazi1 and L. A. I. Kestens1,2 1Ghent University, Ghent, Belgium. 2Delft University of Technology, Delft, The Netherlands.

Grain fragmentation and rotation of crystallographic orientations

have been the subject of many studies for decades. However, there

are still many ambiguities about the role of microstructural

parameters, especially grain boundaries, on these phenomena. The

reason of these ambiguities is mainly due to the lack of substantial

quantitative and comprehensive information. In this study, wide-

field conventional and 3D EBSD are employed to study the deformed

grains in an aluminum polycrystal, subjected to successive plane

strain compression test up to 30% deformation. Serial sectioning,

which includes consecutive steps of material removal and EBSD

measurement were employed to extract a stack of two-dimensional

sections of annealed and deformed samples and to reconstruct the

3D volumes.

Grain Boundary Character Distribution (GBCD) was derived from the

reconstructed 3D volume. The effect of the grain boundary affected

zone (GBAZ) was studied considering the local changes in

microstructure and crystallography in the vicinity of grain

boundaries. It was shown that at the early stages of deformation,

the crystals rotate and the grains are subdivided by the formation of

a rotation front, which was initiate at some specific grain

boundaries. After further deformation, the rotation front sweeps

through the grain and its misorientation increases simultaneously.

The experimental results of the crystal lattice rotation during

deformation were compared with the predictions of different crystal

plasticity models to the purpose of model validation.

Characterization of Grain Boundary Cracking Susceptibility in Pipeline Steels using Electron Backscatter Diffraction M.K. O’Brien, K.O. Findley

Colorado School of Mines, Golden, CO, U.S.A.

In the oil and gas industry, there is a desire to develop higher

strength low carbon steel pipelines that can be used at higher

operating pressures in sour service environments. The elevated

levels of hydrogen sulfide present in sour service environments are

thought to promote hydrogen ingress and cause internal cracking.

This process is known as hydrogen induced cracking (HIC).

Resistance to HIC is generally thought to decrease with increasing

strength levels. Therefore, it is desirable to understand the factors

that control susceptibility to HIC.

In this investigation, X52 and X70 steels were charged with hydrogen

to generate HIC, sectioned, and subsequently characterized using

electron backscatter diffraction (EBSD). Both X52 and X70 are low

carbon steels, with the former having a mixed ferrite/pearlite

microstructure, and the latter having a non-equiaxed, highly

substructured ferritic microstructure. Both steels have undergone

different thermomechanical processing paths that have resulted in

different grain boundary textures. To compare the as-received grain

boundaries to the damaged grain boundaries, misorientation angle

profiles and misorientation distribution functions with

accompanying discrete damaged plots were prepared. Most of the

coincident site lattice boundaries that occur with the highest

multiple of a random distribution (MRD) in the as-received samples

do not appear resistant to cracking, such as Σ27a in the X70 and

Σ13b in the X52 alloy. Σ3 boundaries in both the X52 and X70 alloys

were not resistant to cracking, unlike findings in many FCC systems.

In X70 however, Σ29a boundaries, which occur at the highest

multiple of a random distribution (MRD) in the as-received

microstructure, appear to be resistant to cracking.

ABSTRACTS FRIDAY AM - PLENARIES 107

FRIDAY AM PLENARY SESSION

Grain-Orientation-Dependent Fatigue Damage in Polycrystalline Materials Y.D. Wang1, W. Liu2, R.G. Li1 and S.L. Li2 1State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing, China. 2Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.

The development of multiscale stresses under complex cyclic deformation modes is closely related to not only the evolution of texture but also the

localized damage in polycrystalline materials. For polycrystalline metals with the anisotropy in elasticity and plasticity, the stress gradient may vary

from several millimeters in engineering components serviced in complex stress fields, to micrometers caused by the existence of grain-to-grain or

phase-to-phase interaction, and even to submicrometer inside each grain due to strain/stress incompatibility over the whole plastic deformation.

The difference in deformation modes such as dislocation slip, mechanical twinning and phase transformation also enhances the complexity for

evaluating the multiscale stress distribution and local grain rotation. The advanced characterization methods, such as neutron diffraction,

synchrotron-based high-energy X-ray diffraction and X-ray micro-diffraction, indeed provide effective tools for studying the micromechanical

behavior, by which the multi-scale distribution in stress, grain rotation and localized damage can be well bridged in combination with the multiscale

crystal plasticity simulations. This presentation will give our recent work on the studies of micromechanical behaviors in fcc and hcp metals by the

state-of-the-art X-ray micro-diffraction and high-energy X-ray diffraction techniques with a focus on evolution of grain-orientation-dependent

stress and localized damage during cyclic deformation. Our experiments reveal directly the local grain orientation gradient and the evolution of

sub-micron scale stress distribution caused by specified dislocation configurations near localized shear bands. The experimental data provide local

stress distributions for verifying dislocation-based physical mechanisms on fatigue damage and to develop a local damage criterion for robust

fatigue life estimation.

Making and Breaking of Minerals, Rocks and Planets: A Textural Perspective S. Piazolo School of Earth and Environment, University of Leeds, UK.

In the geosciences, textures along with spatially controlled crystallographic orientation analysis is mainly used for deformation studies in the

crystal-plastic field. In these studies, the main interest lies either in deciphering the underlying processes of strain localization or in the geophysical

expression of textures indicative of deformation conditions in the deep Earth. However, in other research areas, orientation relationships can be

just as important. In the field of biomineralization, textural analysis shows that there is a distinct interplay between crystal growth regulated by the

organism itself and subsequent growth governed by the physics of crystal growth alone. The product is of exceptional strength and toughness.

Geological materials are commonly polymineralic and through in-flux of reactive hydrous fluid, melt or gas reactions occur at variable temperature

and pressure conditions. In many cases, the sequence of reactions and their progression is pivotal to our understanding in Earths’ or planetary

evolution.

The possibility to combine textural analysis with chemical analysis at a similar scale allows for new exciting avenues of research. For example, the

replacement reaction of a mineral (e.g. KBr) by another similarly structured mineral (e.g. KCl) results in textural relationships that can be easily

misinterpreted as microstructures originating from crystal plastic deformation unless the orientation relationships are studied in detail (1).

Similarly, if a feldspar, the most common mineral in the lower crust of the Earth, reacts with a reactive fluid, it will form complicated reaction and

inclusion textures, which if analyzed in detail can be used to determine the relative sequence of events (2).

The advent of Transmission Kikuchi Diffraction enabling orientation and chemical analysis at the nanometer scale (3) opens up new research fields,

promising to transform our understanding of geological processes at a fundamental level. For example, details of inter- and intragrain

crystallographic orientation relationships can help to determine if the enigmatic diamond aggregate “carbonado” has an extraterrestrial or

terrestrial origin (4). Furthermore, in-depth analysis of nanoscale reaction rims open up new avenues to understanding deep mantle processes.

Magnetite growth at the interface between pyrrhotite and diamond, allows for the first time to pinpoint the details of the carbon cycle deep within

the mantle (5). In fault zones nanoscale deformation structures are common; deciphering their origin and rheological consequence is essential for

hazard management. Preliminary data on experimental carbonate rich fault rocks show that during subseismic slip twin formation and dislocation

accumulation at grain boundaries along with brittle failure result in the production of a weak texture and nanoscale particles. Further deformation

causes mechanical dissociation producing amorphous carbon. However, different to common believe, little rheological weakening occurs with

these processes.

[1] Spruzeniece et al. (2017) Nat. Comms. 8. [2] Spruzeniece et al. (in press) Journal of Metamorphic Petrology [3] Trimby (2012) Ultramicroscopy 120, 16 [4] Piazolo et al. (2016) Lithos 265, 244

ABSTRACTS FRIDAY AM - PLENARIES 108

[5] Jacob et al. (2016) Nat. Comms. 7.

ABSTRACTS FRIDAY AM - DEFORMATION 109

Symposium D: Deformation Textures Session: Advanced Materials

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

Development of crystallographic texture under shear strain in ultrahigh-strength strip steels A. Kaijalainen1, D. Lindell2, B. Hutchinson2 and D.A. Porter1 1Materials and Production Engineering, University of Oulu, Finland. 2KIMAB, Stockholm, Sweden.

The effect of subsurface microstructure on the crystallographic

texture of three 8 mm thick low-alloyed hot-rolled and direct-

quenched ultrahigh-strength strip steels with yield strengths in the

range 800 – 1100 MPa has been investigated. Detailed

microstructural features were further revealed by LCSM, FESEM and

FESEM-EBSD. Rolling to lower finish rolling temperatures increased

austenite pancaking leading to the formation of ferritic/granular

bainitic and the upper bainitic microstructures at the subsurface. In

addition, increased austenite pancaking was found to increase the

intensities of ~{112}<111>α and ~{110}<112>α - {110}<111>α texture

components in the surface layers, especially in upper bainitic

microstructures.

It is well known, that while austenite is deformed by rolling below

non-recrystallization temperature, there are shear texture

components in the austenite close to the rolled surfaces, i.e.,

{111}<211>γ and {112}<110>γ. After cooling and transformation to

ferrite these lead to the formation of shear components

{112}<111>α, {110}<112>α and {110}<111>α. However, specific

reason for the higher intensity of ~{112}<111>α texture component

in upper bainitic microstructure has not been sufficiently

investigated. Therefore, the influence of variant selection during the

transformation of austenite to the various ferritic microstructures

will be discussed.

Effect of Processing Methods on Texture Evolution and Recrystallization Studies on 14YWT Nanostructured Ferritic Alloys E. Aydogan1, S.C. Vogel1, S.A. Maloy1, C.A. Yablinsky1, O. Anderoglu2, G.R. Odette3 1Los Alamos National Laboratory, Los Alamos, NM, USA. 2University of New Mexico, NM, Albuquerque, USA. 3University of California Santa Barbara, Santa Barbara, CA, USA.

Nanostructured ferritic alloys (NFAs) are attractive materials for core

components in Generation IV reactors because of their excellent

high temperature strength, stability, and radiation damage

resistance [1-6]. It is very crucial to understand the microstructural

changes occurring during their processing and service. In this

research, two sets of experiments were conducted. First, the

stability of the 14YWT microstructure at different deformation levels

was investigated at temperatures above 1000 °C by an in-situ

neutron diffraction and electron backscatter diffraction techniques.

It has been found that the microstructure is very stable and

recrystallization starts at varying times depending on temperature

and deformation level. Second, texture of 14YWT cladding tubes,

produced either by spray forming followed by hydrostatic extrusion

or hot extrusion and cross-rolling followed by hydrostatic extrusion

has been studied using the above stated diffraction techniques at

room temperature. It has been found that hydrostatic extrusion

which is a combination of plane strain and shear deformations and

hot extrusion and cross-rolling which are plane strain deformations

result in distinct texture results. Moreover, although the total strains

are similar, shear dominated deformation leads to much lower

texture indexes compared to plane strain deformations.

[1] R.L. Klueh, D.J. Alexander, J. Nucl. Mater. 233–237 (1996) 336–

341. [2] G.R. Odette, M.J. Alinger, B.D. Wirth, Ann. Rev. Mater. Res. 38

(2008) 471–503. [3] S. Ukai, S. Ohtsuka, Energy Mater. 2 (2007) 26–35. [4] G.R. Odette, D.T. Hoelzer, JOM 62 (9) (2010) 84–92. [5] S. Ukai, in: Comprehensive Nuclear Materials, Elsevier B.V.,

Germany, Volume 4, Ch. 4.08, 2012. [6] G.R. Odette, JOM, 66(12) (2014) 2427-2441.

Spatially resolved texture and microstructure evolution of gas gun deformed SUS304 steel using neutron diffraction S. Takajo1, 2, C. P. Trujillo1, D. T. Martinez1, B. Clausen1, D. W. Brown1 and S. C. Vogel1 1Los Alamos National Laboratory, Los Alamos, USA. 2JFE Steel Corporation, Kurashiki, Japan.

Crystallographic phases in deformed SUS304 stainless steel, such as

martensitic phase by strain-induced martensitic transformation,

have long been investigated but there are few reports on its

quantitative analysis and texture. In this study, we report

characterization of a 38.1mm-long and 7.62mm-caliber SUS304

cylindrical projectile produced by additive manufacturing. The

projectile was accelerated at 235 m/s using the Taylor Anvil Gas Gun

Facility at LANL, impacting a high-strength steel anvil, leading to a

huge strain gradient inside the sample. Spatially resolved neutron

diffraction measurements on the HIPPO and SMARTS beamlines at

LANSCE with Rietveld and single peak analysis were used to

quantitatively evaluate volume fractions of , , and -phases as well

as residual strain and crystallographic texture, thus providing a

complete picture of the bulk micro-structural evolution. The neutron

diffraction measurements were complemented by EBSD analysis. It

was clarified that the -phase with {200} planes perpendicular to

the deformation axis was increased up to 5 volume percent by the

strain imposed during the deformation and no more than 1 volume

percent of -phase was formed, but only in the very slightly

deformed volume where little amount of -phase was detected.

These results suggested that the {200} texture evolution of (’)

phase during strain-induced martensitic transformation was hardly

ABSTRACTS FRIDAY AM - DEFORMATION 110

influenced by the existence of -phase. The data was compared to

an undeformed reference sample.

Texture Evolution Analysis in Oxide Dispersion Strengthened Ferritic Steel Transformed by a Tube Pilgering Process E. Vakhitova1,2, D. Sornin1 and M François2

1DEN-Service de Recherches Métallurgiques Appliquées, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France. 2 Troyes University of Technology (ICD-LASMIS), 10010, Troyes, France.

Ferritic Oxide Dispersion Strengthened (ODS) steels are investigated

as potential materials for cladding tubes of advanced Sodium Fast

Reactors. Pilgering process is used to cold-form the ODS seamless

tubes with a large cross-section reduction in a double processing

step. To estimate the influence of process parameters on the

material, a microstructure analysis is carried out by Electron

Backscattering Diffraction (EBSD) and X-ray Diffraction (XRD)

methods. These data were used to obtain information about

crystallographic texture, misorientation distributions, grain size, low

and high angle boundary fractions and Schmid factor. Pilgered

samples show a high texture formation with the well-known α-fiber

preferential orientation along the rolling direction. During the heat

treatment process, grain morphology is restored from elongated

grains to the almost equiaxed ones, while the texture presents

unexpected increasing of fiber intensity. The remarkable

temperature stability of this fiber is assumed to be linked to the

texture memory of crystallographic structure during severe cold

rolling process. The special attention was paid to the slip activation

mechanism during plastic deformation applied by pilgering process.

To predict this specific texture formation, modeling investigation of

tube deformation process is performed using a polycrystalline self-

consistent visco-plastic (VPSC) code. Pilgering forming is modeled by

a sequence of deformation path considering the initial grain

orientation sets obtained from EBSD maps results. It assumes a

simple cyclic loading paths estimating the experimental loading

associated to the pilgering process. The effect of initial and induced

texture on the mechanical hardening is estimated and a set of

hardening parameters is identified. Finally, the results of the traction

tests along the rolling and transverse directions are compared to the

numerical simulations.

EBSD analysis of orientation gradients at grain boundaries N. De Vincentis1, A. Roatta1,2, M. Avalos1, R.E. Bolmaro1 and J.W. Signorelli1,2 1IFIR-UNR-CONICET, Rosario, Argentina. 2Facultad de Cs. Exactas, Ing. y Agrimensura (FCEIA-UNR), Rosario, Argentina.

The goal of this paper is to analyze the orientation gradients

developed in grain boundaries of a deep drawing quality steel

(AKDQ) with increasing deformation. The analysis was performed

using a notched specimen subjected to uniaxial tension interrupted

at different strain levels. The microstructure developed in different

zones through the notch at each strain condition was characterized

at sub-grain level spatial resolution using Electron Backscatter

Diffraction (EBSD). This configuration allowed to determine the local

evolution of the misorientation gradients developed in each grain

boundary of the selected zones. It was observed that the

misorientation decreased from the grain boundary to the core of the

grain, defining a region of influence of the grain boundary inside

each of its neighboring grains. In spite of the strictly-local

characteristic of the gradient, it was observed that the severity of

these grain boundary regions increased with mesoscopic plastic

strain, and that their width did not depend on grain size.

ABSTRACTS FRIDAY AM – RECRYSTALLIZATION 111

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

Effect of Annealing Temperature on the Texture and Magnetic Barkhausen Noise of a Non-Oriented Electrical Steel (0.88 wt% Si) after Inclined Cold Rolling Youliang He1*, Mehdi Mehdi1, 2, Erik J. Hilinski3, Afsaneh Edrisy2 1CanmetMATERIALS, Natural Resources Canada, Hamilton, Ontario, Canada L8P 0A5. 2Department of Mechanical, Automotive, and Materials Engineering, University of Windsor, Windsor, ON, Canada N9B 3P4. 3Tempel Steel Co., Chicago, IL, USA 60640-1020

Non-oriented electrical steels are widely used in rotating machines,

electric vehicles or windmills as the lamination core for the electric

motors or generators. The crystallographic texture of the steel sheet

has a significant effect on the magnetic properties of the magnetic

core, thus affecting the performance and energy efficiency of the

motors or generators. To obtain the ideal <001>//ND (normal

direction) texture in the final steel sheets, inclined cold rolling was

employed in this research to process a 0.88 wt% Si non-oriented

electrical steel. After conventional hot rolling and annealing, the

steel was cold rolled at various angles (e.g. 0, 45, and 90) to the

hot rolling direction (HRD) with a thickness reduction rate of ~78%.

The cold-rolled sheets were then annealed at different temperatures

from 600 to 750C for 30 s to investigate the effect of annealing

temperature on the recrystallization and the formation of texture.

The microstructure and microtexture were characterized by optical

microscopy and electron backscatter diffraction (EBSD), and the

magnetic properties were evaluated by magnetic Barkhausen noise

(MBN) analysis. It was found that the cold-rolled steel partially

recrystallizes at 600C and 650C, and the progress of

recrystallization differs in samples incline-rolled at different angles

to the HRD, i.e. samples cold rolled at 45 to the HRD recrystallize

faster than the conventional (0 to HRD) or cross rolled (90 to the

HRD) samples. The initial cold rolling texture (mainly <110>//ND)

changes to the <001>//ND texture at lower annealing temperatures

(600 and 650C), while at higher temperatures (700 and 750 C), the

<111>//ND texture appears together with the strengthening of the

<001>//ND texture. The Magnetic Barkhausen noise of the samples

annealed at lower temperatures exhibits much higher values than

those annealed at higher temperatures. The anisotropy of MBN in

the conventionally rolled steel is apparently higher than those

incline-rolled or cross-rolled samples.

Study of the recrystallization kinetics in Fe3%Si steels during the 1st recrystallization using misorientation derived parameters (EBSD) in the CGO process F. Cruz-Gandarilla1, H.F. Mendoza-Leon2 R.E. Bolmaro3, A.M. Salcedo-Garrido1, J.G. Cabañas-Moreno4 and M. Avalos3 1Escuela Superior Física y Matemáticas. Instituto Politécnico Nacional, Ciudad de México, México. 2Centro de Nano micro y Nano Tecnología. Instituto Politécnico Nacional, Ciudad de México, México. 4Instituto de Física Rosario. CONICET. Universidad Nacional de Rosario. Rosario, Argentina. 4CINVESTAV IPN, Ciudad de México,

México

Fe3%Si alloys with Goss texture are essential in the manufacture of

electrical transformers. Obtaining these materials requires several

different sub-processing stages, like the one called primary

recrystallization, fundamental key process preceding abnormal grain

growth. The structure of grains and the different microstructural

aspects of this stage will determine the conditions for developing

the Goss orientation during abnormal grain growth [1].

The kinetics of recrystallization have been characterized by studying

properties, dependent on recrystallized volume, like hardness,

volume fractions of texture components, etc. The evolution of the

recrystallized volume has been modeled following the Johnson-

Mehl-Avrami-Kolmogorov (JMAK) formalism [2]. Recrystallized and

non-recrystallized grains are not uniquely characterized by these

global methods and a more local characterization is needed.

Recovery and recrystallization happening during heat treatments

involve changes in dislocation densities and their characteristic

arrangements, which are reflected in the measurements of

misorientations. Grain Orientation Spread (GOS), Grain Average

Misorientation (GAM), Kernel Average Misorientation (KAM), etc.

are useful parameters calculated from EBSD data to study these

variations [3].

The purpose of this work was to use those magnitudes (GOS, GAM

and KAM) calculated from several EBSD scans, performed at

increasing heat treatment times, to characterize the kinetics of the

1st recrystallization in an Fe3%Si alloy. Hardness measurements were

made simultaneously in order to validate the evolution of the

recrystallization by classical ways. It was found that the global GOS

(including grains of all orientations) shows a behavior similar to

hardness. When grains belonging to separate texture components

are analyzed, gamma grains are the first ones to recrystallize and

alfa grains the last. A further study is necessary to determine limits

for those parameters below which grains can be considered

recrystallized. The experiments suggest so far that there are not

unique values for all texture components.

[1] F. Cruz-Gandarilla, R. Penelle, T. Baudin, H.F. Mendoza León and J. G. Cabañas-Moreno. (2008) Proceedings of the 15th ICOTOM. Ceramic Transactions, Volume 200. 123, Ed. WILEY.

[2 F.J. Humpherys and M. Hatherly. RECRYSTALLIZATION AND RELATED ANNEALING PHENOMENA. (2004) 2dn Ed. ELSEVIER. ISBN: 0 08 044164 5

[3] F. Cruz-Gandarilla, A.M. Salcedo-Garrido, R.E. Bolmaro, T. Baudin, N.S. De Vincentis, M. Avalos, José G. Cabañas-Moreno, H.F. Mendoza-León. (2016) Materials Characterization 118, 332

Texture Evolution of a 3.2 wt% Si Non-Oriented Electrical Steel during Hot Band Annealing Mehdi Mehdi1, 2, Youliang He1, Erik J. Hilinski3, Afsaneh Edrisy2 1CanmetMATERIALS, Natural Resources Canada, Hamilton, ON, Canada L8P 0A5. 2Department of Mechanical, Automotive, and Materials Engineering, University of Windsor, Windsor, ON, Canada N9B 3P4. 3Tempel Steel Co., Chicago, IL, USA 60640-1020

ABSTRACTS FRIDAY AM – RECRYSTALLIZATION 112

To optimize the magnetic properties of non-oriented electrical

steels, it is required to carefully control all the stages of

thermomechanical processing during the production of the steel

sheets, since the microstructure and crystallographic texture at an

early stage will usually affect those at the subsequent stages. Many

studies have shown that hot band annealing may have a positive

effect on the texture of the final sheet, but it is not clear what are

the optimal annealing conditions to obtain the desired final textures.

In this study, the evolution of microtexture and microstructure of a

3.2% Si electrical steel during hot band annealing is studied by

tracking the nucleation and grain growth through electron

backscatter diffraction (EBSD) examinations. A region of the hot-

rolled sample was marked by micro-indents so that the same area

could be examined at various annealing times (under the same

temperature) to investigate the evolution of the microstructure and

microtexture during recrystallization. In this way, the mechanisms of

nucleation and grain growth can be elucidated, and optimal

annealing conditions can be determined.

Effect of solute Sn on the evolution of primary recrystallization texture in 3% Si-Fe R. Suehiro, Y. Hayakawa and T. Takamiya

Steel Research Laboratory, JFE Steel Corporation, Kurashiki, Japan

Solute atoms affect the formation of primary recrystallization

texture in 3%Si-Fe. In this study, effect of Sn addition in 3% Si-Fe

alloy on the evolution of primary recrystallization texture was

investigated. In the experiment, two steels, Sn-free (3.2mass% Si-

0.06mass% Mn) and Sn-bearing(3.2mass% Si-0.06 mass% Mn-0.1

mass% Sn) were cold rolled with 88% reduction rate and annealed

for primary recrystallization. The main texture component of

recrystallization texture just after completion of primary

recrystallization were almost similar {111}<112> in both steels. After

grain growth annealing at 850 °C, strong {111}<112> texture was

preserved in Sn-free steel, while strong {411}<148> texture

developed in Sn-bearing steel. In this study, the relationship

between solute Sn and the change of texture during grain growth

was focused on. The grain boundary misorientation angle

distribution f(ω) was calculated using EBSD. In Sn-free steel, f(ω) of

grain boundary with low misorientation angle ω(ω = 0-15°)

surrounding {111}<112> grains decreased significantly during grain

growth. On the other hand, almost no change of f(ω) in low ω region

was observed in Sn-bearing steel. For grain boundaries surrounding

{411}<148> grains, f(ω) with ω = 15-45° decreased and the

decrement of f(ω) was almost same for both steels. The decrease of

f(ω) during grain growth can be related to grain boundary motion. If

grain boundaries with specific ω move during grain growth,

frequency of these boundaries should decrease. Considering this

assumption, it can be considered that the movement of grain

boundaries surrounding {111}<112> grain was suppressed by the

existence of solute Sn. The grain boundary with low misorientation

angle (ω = 0-15) has lower mobility compared with high

misorientation angle (ω = 15-45) boundary. Since Sn is known as

grain boundary segregation element, following mechanism was

suggested. Sn segregates at grain boundaries surrounding

{111}<112> grains and suppresses the movement of low ω

boundaries during grain growth by Solute drag effect. In contrast,

Segregation of Sn to boundaries surrounding {411}<148> grains is

weakened since solute Sn atom cannot follow highly mobile

boundaries and weak Solute drag effect is exerted on these

boundaries. Therefore {411}<148> grains developed preferentially

during grain growth in Sn-bearing steel.

Influence of cold rolling reduction on secondary recrystallization textures in Fe-3%Si sheet T. Kataoka1, H. Atsumi1, N. Morishige1, M. Yasuda2 and K. Murakami2 1Hirohata R&D Lab., Nippon Steel & Sumitomo Metal Corporation, 1 Fuji-cho, Hirohata-ku, Himeji, Hyogo Prefecture, 671-1188 Japan. 2Yawata R&D Lab., Nippon Steel & Sumitomo Metal Corporation, 1-1 Tobihatacho, Tobata-Ku, Kitakyusyu City, Fukuoka Prefecture, 854-8501 Japan

In Fe-3%Si sheet, Goss ({110} <001>) orientation is the major

component of the secondary recrystallization texture. In order to

clarify the mechanism of the orientation selectivity in the secondary

recrystallization, many studies1-3) of the relationship between

primary recrystallization textures and secondary recrystallization

textures have been conducted. However, the mechanism of the

orientation selectivity in the secondary recrystallization has not

been perfectly clear yet.

The purpose of this work is to elucidate the influence of the primary

recrystallization textures on the secondary recrystallization textures

in Fe-3%Si sheet and to clarify the mechanism of the orientation

selectivity in the secondary recrystallization.

In this work, we demonstrate the primary recrystallization textures

and the secondary recrystallization textures of Fe-3%Si sheet. All the

sheets have the same thickness of 0.22mm, but the cold-rolling-

reduction rates are different, i.e., 90, 93 and 95%.

From our experimental results, the primary recrystallization textures

changed with the cold-rolling-reduction rates and consequently the

secondary recrystallization textures changed. Regarding the samples

cold-rolled at reduction rates of 90 and 93%, the major components

of the secondary recrystallization textures were {110} <001>. On the

other hand, the secondary recrystallization textures of the sample

cold-rolled at a reduction rate of 95% were mixtures of {110} <001>

and {110} <112> components. By comparing the frequency of Σ9

coincidence grains in the primary recrystallization textures with the

secondary recrystallization textures, we suggest that the grains

having the high frequency of Σ9 coincidence site lattice boundaries

play a key role in determining on the secondary recrystallization

textures.

[1] Y. Yoshitomo, Y. Ushigami, J. Harase, T. Nakayama and N. Takahashi (1994) Acta Metall, Mater 42, 2593.

[2] S. Arai, Y. Ushigami and N. Takahashi (1996) Mater. Sci. Forum 204, 617.

[3] T. Imamura, Y. Shingaki and Y. Hayakawa (2013). Metall and Mat Trans A 44, 1785.

ABSTRACTS FRIDAY AM - NUMERICS 113

Symposium N: Mathematical, Numerical and Statistical Methods of Texture Analysis Symposium Chair:

Dr. Oliver Johnson, Department of Mechanical Engineering, Brigham Young University

Spectral database constitutive representation within finite element and spectral micromechanical solvers for computationally efficient crystal plasticity modelling Marko Knezevica, Miroslav Zecevica, Daniel Savagea, Rodney J. McCabeb aDepartment of Mechanical Engineering, University of New Hampshire, Durham, NH 03824, USA bMaterials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA

This paper presents the advances made in the development and

implementation of a novel approach to speeding up crystal plasticity

simulations of metal processing by one to three orders of magnitude

compared to the conventional approaches, depending on the

specific details of implementation. This is mainly accomplished

through the use of spectral crystal plasticity (SCP) databases

grounded in the compact representation of the functions central to

crystal plasticity computations. A key benefit of the databases is that

they allow for a non-iterative retrieval of constitutive solutions for

any arbitrary plastic stretching tensor (i.e., deformation mode)

imposed on a crystal of arbitrary orientation. Additionally, the

approach takes the advantages of a specialized computer hardware

integrating a graphics-processing unit and data compactions

methods based on the generalized spherical harmonics texture

representation. The paper emphasizes embedding SCP databases

within implicit finite elements and spectral micromechanical solvers.

To illustrate the potential of these novel implementations, results

from several process modeling applications including equi-channel

angular extrusion and rolling are presented and compared with

experimental measurements and predictions from other models.

A Model Based Iterative Reconstruction Algorithm for Pole Figure Inversion S. Singh, P. Kc and M. De Graef Carnegie Mellon University, Pittsburgh, USA.

The central problem in quantitative texture analysis involves the

determination of the Orientation Distribution Function (ODF), which

can be used to calculate orientation-averaged bulk anisotropic

quantities. Since this is such an important quantity of interest for

polycrystalline materials, there has been considerable effort in this

area. There are two primary methods for determining the ODF; one

approach uses the point-by-point orientation of grains using

electron diffraction techniques (EBSD, TKD) while the other

technique relies on using 2-D Pole Figures (PF) obtained by x-ray

diffraction (XRD). The first method allows for the direct computation

of the ODF, while the second method requires additional analysis to

reconstruct the ODF from the PFs; this reconstruction problem is

formally known as the Pole Figure Inversion problem. It has been

well known that the Pole Figure Inversion problem has many

parallels with the standard tomography problem. Because of

significant recent advances made in scalar tomographic

reconstruction techniques, it becomes meaningful to revisit the

inversion problem.

This contribution describes a new discrete method for inverting PFs

to estimate the ODF. Our approach makes use of a newly

constructed modified equal area Lambert projection for uniformly

sampling the 2-sphere S2 and combines this with the equal volume

“cubochoric” orientation representation used to obtain a uniform

sampling of orientation space, SO(3). Furthermore, a Model Based

Iterative Reconstruction (MBIR) algorithm with a q-Generalized

Gaussian Markov Random Field (q-GGMRF) prior model is used to

formulate the problem as a maximum a posteriori probability (MAP)

estimation problem. Thus, formulated objective function is

iteratively minimized to deduce the MAP estimate of the ODF. The

q-GGMRF parameters are fine-tuned to produce sharp or diffuse

textures. The efficacy of the new method will be evaluated with

both model and real experimental data and compared with existing

software including the MatLab based MTEX toolbox and the publicly

available software package popLA.

Mean-field modeling of recrystallization textures Miroslav Zecevica, Ricardo A. Lebensohnb, Rodney J. McCabeb, and Marko Knezevica aDepartment of Mechanical Engineering, University of New Hampshire, Durham, NH 03824 USA. bMaterials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87544.

This paper presents recent advances made in extending well-

established texture and deformation mechanisms based mean-field

deformation models such as visco-plastic self-consistent (VPSC) to

predict recrystallization texture evolution. Deformation textures for

cubic and orthorhombic crystal structure materials are predicted

using the VPSC model capable of calculating statistical distributions

of intragranular misorientation fields within grains. The

recrystallization model incorporates laws for nucleation and grain

growth for simulating recrystallization textures. Consistent with

experimental evidence, the nucleation is assumed to occur at

transition bands developing within the grains and at high angle grain

boundaries. Grain growth is driven by the strain energy difference

between the grain and surrounding effective medium. The predicted

recrystallization textures are compared with experiments and

reasonable agreement is obtained in a computationally efficient

manner (computational time is on the order of minutes).

Estimation of the orientation distribution function using incomplete sets of pole figures data H.G. Brokmeier1 1Inst. of Materials Science and Engineering TU Clausthal, Clausthal-Zellerfeld, Germany.

One way to estimate the orientation distribution function (ODF) is

based on mathematical calculations using experimental pole figure

data obtained by X-rays, neutrons and synchrotron-radiations. The

key task of such an experiment is sufficient scanning of the polar

ABSTRACTS FRIDAY AM - NUMERICS 114

sphere for high quality input data for ODF-calculation. On one hand

experiments are in practice time consuming and standard scanning

routines are worldwide in use which may not fit the requirements to

obtain correct textures. Any scanning routine should reflect the pole

figure window, the beam divergence and texture sharpness. One

example is in case of sharp textures in which a pole figure scanning

routine of Δα=5° and Δβ=5° is used. According to standard

instrumental resolution functions, the coverage of the polar sphere

is incomplete and don’t reflect the true texture. On the other hand,

experimental conditions like laboratory X-ray diffraction, or

synchrotron diffraction of large pieces, or in-situ texture evolution

studies lead to different kinds of incomplete sets of pole figure data.

Today ODF-software is easily available, which looks like that all

problems can be solved. Examples will be presented that even

excellent ODF software still needs high quality input data for a

sufficient estimation of the “true ODF”. Texture analysis of Mg and

its alloys is a key task in light-weight materials, but due to the special

texture of Mg it is not easy to get good Mg-textures with all texture

components and texture sharpness by laboratory X-rays. Many

present papers showing recalculated pole figures from the ODF

showing still separate areas for measured part and recalculated part,

which opens the question: how good is the ODF-calculation? A

special situation is also given for in-situ experiments. Mostly, we

have blind areas which can be filled in some cases quite well and in

other cases with some errors by the ODF. One can find this for all

kinds of materials even in high symmetric cubic metals. ODF-

calculation and pole figure measurement have to go hand in hand.

Application of the symmetrized Bingham distribution and other parametric distributions for the modelling of texture uncertainty Stephen Niezgoda, James Matuk, Oksana Chkrebtii and Carl Ahlborg The Ohio State University, Columbus OH, USA.

The estimation of orientation distribution functions (ODFs) from

discrete orientation data, as produced by electron backscatter

diffraction or crystal plasticity micromechanical simulations, is

typically achieved via techniques such as the Williams–Imhof–

Matthies–Vinel (WIMV) algorithm or generalized spherical harmonic

expansions, which were originally developed for computing an ODF

from pole figures measured by X-ray or neutron diffraction. These

techniques often rely on ad-hoc methods for choosing parameters,

such as smoothing half-width and bandwidth, and for enforcing

positivity constraints and appropriate normalization. In general, such

approaches provide little or no guarantees as to their optimality in

describing the given dataset. In the current study, a finite mixture of

Bingham distributions, symmetrized to reflect arbitrary

crystallographic and sample symmetry, is used to estimate ODFs

from discrete orientation data. Two algorithms will be discussed i)

an unsupervised learning approach which introduces a minimum

message length criterion, a common tool in information theory for

balancing data likelihood with model complexity, to determine the

number of components in the Bingham mixture and ii) an optimal

Bayesian inference approach which uses a birth-death Markov chain

Monte-Carlo sampling scheme. The latter approach is of particular

interest as it provides a methodology for performing uncertainty

quantification of texture, can provide error bounds on the

orientation distribution function measured from a given sample, and

gives a statistically rigorous framework for comparison of texture

between samples or characterizing the variance in texture across an

ensemble of samples.

ABSTRACTS FRIDAY AM - ENGINEERING 115

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Processing - Forging and Extrusion

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Microstructure and texture evolution during modified multi-axial forging of Magnesium alloy Mg–3Al–0.4Mn Somjeet Biswas Department of Metallurgical and Materials Engineering, Indian Institute of Technology kharagpur, Kharagpur, India.

Wrought Magnesium (Mg) alloys have high potential for

automobile/aerospace structural applications. However, Mg alloy

usage is restricted due to its low strength, low ambient temperature

ductility and high anisotropy owing to its hexagonal closed packed

(hcp) structure. Usage of Mg alloys will lead to the reduction of

carbon emission in atmosphere and thus the environmental impact

of motored vehicles. In this work, an attempt was made to produce

ultra-fine grain (UFG) size and weak texture in a single-phase Mg

alloy Mg–3Al–0.4Mn by modified multi-axial forging (MAF) process.

An average grain size of ~0.4 µm and weak texture could be

achieved. This led to the improvement in strength, room

temperature ductility and reduction in anisotropy. The

microstructural characterization was performed using the electron

back scattered diffraction (EBSD) technique in a field emission gun –

scanning electron microscope (FEG-SEM). Visco-plastic self-

consistent (VPSC) modeling was used to predict the deformation

texture and the underlining deformation mechanism. The grain

refinement mechanism and the associated dynamic recrystallization

and its effect on the deformation texture were studied.

[1] S. Biswas, S. Suwas (2011) Scripta Materialia. 66, 89.

Characterization of microstructure and texture in 6013 aluminum alloy after large strain extrusion machining process Xiaolong Bai1,3, Zhimin Qi1, Srinivasan Chandrasekar2,3, Kevin Trumble1,3

1School of Materials Engineering, Purdue University, West Lafayette, IN, USA. 2School of Industrial Engineering, Purdue University, West Lafayette, IN, USA. 3Center for Materials Processing and Tribology, Purdue University, West Lafayette, IN, USA

Commercial production of 6xxx aluminum alloy sheets consists of

multi-stage hot and cold rolling processes that result in final Cube

(100) [001] and Goss (110) [001] textures, which are unfavorable to

subsequent forming operations. In this study, large strain extrusion

machining (LSEM), a technique to impose large shear strains at high

strain rate within a narrow deformation zone, was employed to

make thin strip directly from as-cast AA6013 alloy. The resultant

microstructure after LSEM processing contains three different zones:

the primary shear zone due to the shear in the narrow deformation

zone; the secondary shear zone originating from friction between

the cutting tool and sheet; and the constraint zone resulting from

friction between the constraint tool and sheet. The thickness of the

three zones, especially the primary shear and constraint zone, can

be controlled by deformation parameters (strain, strain rate and

temperature). Partial {111} and <110> fiber textures are developed

during the LSEM process of the AA6013, which is characteristic of

FCC metals exposed to simple shear deformation. Due to the friction

effect, however, the shear angles in the three zones are different

and can be controlled by the deformation parameters.

Microstructures of as-cast and as-deformed materials are

characterized by optical microscopy and crystallographic textures

are analyzed by x-ray diffraction. The results are compared with

those from the conventional rolling process and the advantages and

applications are discussed.

Microstructure and Texture Evolution of Magnesium alloy after Shear Assisted Processing and Extrusion (ShAPE) M. Jamalian1, V. Joshi2 and D.P. Field1

1School of Mechanical and Materials Engineering, Washington State University, Pullman, USA. 2Pacific Northwest National Laboratory, Richland, USA

Magnesium alloys have been an area of interest in various industries

such as transportation due to the high strength and low density.

However, a limitation of utilizing magnesium is the inability of

forming it. An effective way of achieving optimum mechanical

properties is modifying grain size and texture. Shear Assisted

Processing and Extrusion (ShAPE) is a novel process that is used for

fabricating thin-walled magnesium tubing. This study analyzes the

microstructure and texture of the alloy at various stages of the

process by using electron backscatter diffraction (EBSD). Notable

differences in grain size and texture were observed depending on

location examined within the extrusion. Wall thicknesses of 60 and

120 mils were characterized showing that the grain size and basal

plane orientation changed significantly as a function of position

within the extrudate, with especially severe changes near the edges.

This type of microstructural information can be used to tune the

parameters of ShAPE.

Texture development in Al-Mg-Si alloys extruded through porthole dies Jingqi Chen 1, Yahya Mahmoodkhani 2, Yu Wang2, Nick C. Parson3, Mei Li4, Mary A. Wells2, and Warren J. Poole1 1The University of British Columbia, Vancouver, British Columbia, Canada. 2University of Waterloo, Waterloo, Ontario, Canada. 3Rio Tinto Aluminium, Jonquière, Québec, Canada. 4Ford Motor Company, Dearborn, Michigan, USA

The extrusion of hollow profiles from aluminum alloys can be done

use a porthole die. In a porthole die, the aluminum is split into

multiple feeds which pass around a bridge in the die and then re-

weld together. In this work, an idealized porthole die was used

where a round billet was extruded into a strip with a bridge in the

centre of the strip. The material used in the trials was an aluminum

alloy based on AA6082 with a high dispersoid content to inhibit

ABSTRACTS FRIDAY AM - ENGINEERING 116

recrystallization. The texture and microstructure was characterized

by electron backscatter diffraction maps. In comparison with the

conventional strip extrusion where there is no bridge in the die, the

porthole die extrusion displays a strong texture variation around the

centre weld line. Moreover, the conventional strip extrusions had a

typical plane strain deformation texture seen for high temperature

deformation of aluminum, i.e. a mixture of copper, S, and brass

orientations. In contrast, the porthole die extrusion exhibits

individual texture components which vary from the near the weld

line. In detail, for the areas close to the centre weld line, only the

copper-type texture can be observed, whereas about 0.4 mm from

the weld line, as single component of the brass texture is observed.

To explain this phenomenon, a combination of fine-element method

and visco-plastic self-consistent texture simulations was employed

to predict the variation of texture components around the weld line.

Synergic effect of Mg addition and hydrostatic extrusion on microstructure and texture of biodegradable low-alloyed zinc A. Jarzębska1, M. Bieda1, J. Kawałko1, P. Koprowski1, Ł. Rogal1, K. Sztwiertnia1, B. Kania1, R. Chulist1, W. Pachla2, M. Kulczyk2 1Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Krakow, Poland. 2Institute of High Pressure Physics, Polish Academy of Sciences, Warszawa, Poland

The purpose of researches was to investigate the influence of

different content of Mg combine with plastic deformation in the

room temperature on microstructure and texture of low-alloyed zinc

(ZnMg). In order to study those effects Zn alloys with various

amount of Mg were casted and subsequently subjected to

hydrostatic extrusion (HE) and compared to pure zinc. Detailed

analysis of microstructure and local texture of obtained materials

was received from scanning electron microscope observation and

electron back scatter diffraction experiment and was performed on

both longitudinal and transvers cross sections of each sample.

Information about the global texture has been investigated with the

use of X-ray diffraction technique.

Results showed that HE led to grain refinement on the level that was

unattainable for classical methods of deformation both in pure Zn

and in ZnMg alloys. Microstructure of pure Zn was characterized by

equiaxed grains on both cross sections. This observation together

with local and global texture analysis received from transverse cross

section suggest occurrence of dynamic recrystallization during

plastic deformation. Addition of Mg caused major changes in

microstructure and texture of deformed materials and provoked

even larger grain refinement. On longitudinal cross section of ZnMg

bimodal structure composed of elongated grains in extrusion

direction and equiaxed one's were noticed.

Hydrostatic extrusion and alloying caused great modification in

microstructure and texture of low-alloyed zinc which corresponded

to significant improvement in mechanical properties.

ABSTRACTS FRIDAY AM - ENGINEERING 117

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Engineering Processes

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

Material Forensics H. Garmestani1, E. Hoar1, A. Tabei1, Z. Pan1, S. Liang1, D. Shih2 1Georgia Institute of technology, Atlanta, GA, USA. 2Boeing, St. Louis, MI, USA

A review of the research on investigating the effect of high speed

machining on the near-surface microstructures of Al7075 and Ti64 is

presented here. It is shown that the high-speed machining process

can introduce a texture and grain size gradient in the machined

surface in these alloys. A physics-based finite element method is

proposed for the modeling of machining-induced phase

transformation and grain size growth. Prediction of the grain

growth and phase transformation are obtained with the Johnson-

Mehl-Avrami-Kolmogorov (JMAK) dynamic recrystallization model

and Avrami model, respectively [1]. A modified Johnson Cook flow

stress model is embedded into the method to account for the phase

transformation. The accuracy of the proposed method is validated

with experimental data. Parametric studies are conducted to

investigate the effects of the cutting speed and the feed rate on the

microstructure change in machining. The experimental micro-

texture and grain size distribution data are used to develop a

process path model that can be used to link to machining

parameters.

[1] Z. Pan, S. Y. Liang, H. Garmestani, D. S. Shih (2016), Int J Adv Manuf Technol, 87:859–866

EBSD Analysis of Pt-20Ir Wire as Lead Conductor in Implantable Medical Device Kailynn Cho and Bernard. Q. Li Medtronic Neuromodulation, 7000 Central Ave. NE, Minneapolis MN 55432, USA.

Pt-20Ir cold drawn wire has been used as lead conductor in

implantable medical devices. The lead is a device to transfer the

electrical signal to the area for stimulating such as brain and

neurological nerves. The Pt-20Ir wire demonstrated the good

biocompatibility and stability. Although Pt-20Ir wire has been used

in leads more than 20 years, there is lack of published data in

literature on its microstructure. Due to inert nature the Pt and its

alloys are difficult to be prepared as metallography for grain

structure analysis. By using EBSD technique, the Pt-20Ir sample

does not need to be etched and its high atomic number is able to

generate high quality backscatter pattern. In this study, the Pt-20Ir

wire was analyzed for its grain structure, grain boundary and

texture.

Recrystallization and crystal growth phenomena during Rolling Contact Fatigue and White Etching Crack formation of AISI 52100 bearings A. Schwedt1, V. Šmeļova1,2, A. M. Diederichs1,*, M. O. Özel3, T. Janitzky3, J. Mayer1, L. Wang2, C. Broeckmann3, W.Holweger2,4 1Central Facility for Electron Microscopy (GFE), RWTH Aachen University, Aachen, Germany. 2National Centre for Advanced Tribological Studies (nCATS), Faculty of Engineering and the Environment, Southampton University, Southampton, UK. 3Institute for Materials Applications in Mechanical Engineering (IWM), Faculty of Mechanical Engineering, RWTH Aachen University, Aachen, Germany. 4Schaeffler Technologies GmbH & Co. KG, Tribology Fundamentals, Herzogenaurach, Germany. *Present address: Department of Mechanical Engineering, Materials and Surface Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark.

Besides classical Rolling Contact Fatigue (RCF) the unpredictably

occurring formation of White Etching Crack (WEC) networks has

been identified as a major cause of failures of AISI 52100 bearings in

a wide range of applications.

Recent studies have shown that in both cases (for RCF cf. [1], for

WEC cf. [2]) a large variety of microstructural alterations occur, e.g.

in terms redistribution of alloying elements, heterogenization of

local microhardness, and especially recrystallization and growth of

ferritic grains in various grains size ranges and shapes.

EBSD measurements show, that the microtexture of these

components is not random – in the case of high-stress RCF it can be

well connected to the outer rolling conditions ([1]), in the case of

WECs the prevailing textures are more complex and locally varying

within the crack network. An overview of examples from WECs

formed under different conditions and lifetimes will be presented.

The examples comprise failed bearings from real applications, as

well as test samples from various test rigs such as industrial L11 or

L24 test rigs at Schaeffler or a 4-disc test rig at RWTH Aachen

University.

It will be discussed, how far the textures found for the

microstructural alterations in failed and test-rig samples can give

insight into the formation mechanisms of the observed

microstructure alterations.

[1] V. Šmeļova, A. Schwedt, L. Wang, W. Holweger, J. Mayer (in press), Intl. J. of Fatigue, DOI:10.1016/j.ijfatigue.2017.01.035.

[2] A. M. Diederichs, A. Schwedt, J. Mayer, & T. Dreifert (2016), Materials Science and Technology 32, 1683-1693.

Individual effect of recrystallization nucleation sites on texture weakening in a magnesium alloy Dikai Guan, W. Mark Rainforth*, Brad Wynne Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK

ABSTRACTS FRIDAY AM - ENGINEERING 118

Recrystallized grain nucleation, grain growth and corresponding

texture evolution in a cold-rolled rare earth containing WE43 Mg

alloy during annealing at 490 °C was fully tracked using a quasi-in-

situ electron backscatter diffraction method. The results show

nucleation sites, such as double twins, can weaken the deformed

texture and for the first time provide direct evidence that

recrystallized grains originating from double twins can form the rare

earth texture (RE texture) during annealing. The RE texture emerges

during the nucleation of recrystallized grains and is maintained

during subsequent grain growth, which results in a stable RE texture

being developed as recrystallization progresses. Precipitation and

recrystallization occurred concurrently during most of the annealing

period, with precipitates forming preferentially along prior grain and

twin boundaries. These precipitates effectively retard the

recrystallization due to particle pinning leading to an excessively

long time for completion of recrystallization.

Materials-Affected Manufacturing: Inverse Model for the Simulation of Texture Evolution in Ti64 through Turning Eric Hoar1, Zhipeng Pan2, Ali Tabei1, Jason Allen1, Peter Bocchini3, Hamid Garmestani1, Steven Liang2 1School of Materials Science and Engineering, Georgia Institute of Technology. 2G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology. 3Boeing Research & Technology

The goal of materials-affected manufacturing research is to

understand the material evolution during different manufacturing

processes. This project focuses on understanding and simulating the

texture evolution of titanium alloy, Ti64 through the process of

turning. By understanding the texture evolution of Ti64 it is possible

to invert the process. This allows for the determination of a

required initial microstructure in order to reach a specific desired

microstructure through turning. Here we present on our current

results in simulating the texture evolution in Ti64 due to turning.

ABSTRACTS POSTERS 119

POSTER SESSION

Tuesday Evening 7th November 2017

ABSTRACTS POSTERS A 120

Symposium A: Texture and Anisotropy in Advanced Engineering Processes and Materials Session: Advanced Materials

Symposium Chairs:

Professor Tracy Nelson, Department of Mechanical Engineering, Brigham Young University

Dr. Ashley Spear, Department of Mechanical Engineering, University of Utah

A-1 Evolution of microstructure and texture in AA1100 during multi-axial diagonal forging J.-H. Shin1, M.-S. Kim1, S. C. Kwon2, S.-T. Kim2, S.-H. Lee3, S.-H. Yang3, S. Lee3, S.-H. Choi1 and H.-T. Jeong2 1Department of Printed Electronics Engineering, Sunchon National University, Sunchon 57922, Republic of Korea. 2Department of Advanced Metal and Materials Engineering, Gangneung-Wonju National University, Gangneung 25457, Republic of Korea. 3Agency for Defense Development, Yuseong-si, Daejeon 34186, Republic of Korea.

Evolution of microstructure and texture in a commercially pure

aluminum (AA1100) during multi-axial diagonal forging (MADF)

process was investigated by microstructural analysis and polycrystal

modelling. MADF process was developed as a novel severe plastic

deformation (SPD) technique to impose a uniform strain throughout

the whole specimen. Characterization of microstructure in AA1100

was conducted using optical microscope (OM) at each MADF step.

Micro-hardness distribution was used to investigate the strain

homogeneity on cross-sectional plane of forged specimens during

consecutive MADF steps. In order to analyze the evolution of

microstructure and texture on cross-sectional plane of forged

specimens during MADF process, electron backscatter diffraction

(EBSD) technique was applied. Three dimensional finite element

analysis (FEA) using the commercial software (DEFORMTM-3D) was

conducted to simulate the deformation behavior during MADF

process. The deformation history calculated by FEA was used for

visco-plastic self-consistent (VPSC) polycrystal model to predict

microtexture evolution during MADF process. Microstructure of

AA1100 deformed by MADF process exhibited relatively weak

texture and homogeneous microstructure with fine grains compared

to the other SPD processes.

A-2 Development of micro fibril textures in melt-spun polyamide-6 fibers by transversal compression N. Wirch1, R. Ghadimi2, T. Vad3 and T.E. Weirich1,4 1Central Facility for Electron Microscopy (GFE), RWTH Aachen University, Aachen, Germany. 2Tietz Video and Image Processing Systems GmbH, Gauting, Germany. 3Institute for Textile Engineering (ITA), RWTH Aachen University, Aachen, Germany. 4Institute of Crystallography (IFK), RWTH Aachen University, Aachen, Germany.

The investigation of ultrathin cross-sections of melt-spun polyamide-

6 (PA6) fibers by low-dose electron diffraction revealed a hitherto

unknown texture within the plane normal to the main fiber axis. This

texture could only be found in cross section samples with

pronounced ripples and disruptions due to the transversal forces

imposed on the fibers during ultra-thin sectioning. The developed

texture is thus the result of the reorientation of the crystalline nano-

fibrils inside the yarn under transversal compression stress. Using

the results from electron diffraction and complementary

measurements by wide-angle x-ray diffraction (WAXD) on the same

material enabled us to develop a structural model of the interior of

the fibers on the nanoscale. The within this study obtained results

are likely of great interest for calculations of materials properties of

individual fibers and the therefrom obtained products as well.

A-3 Microstructure and Texture of Titanium grade 2 after ECAP Processing M. Wroński1, K. Wierzbanowski*1, R. Z. Valiev2,3, J. Kawałko4, K. Sztwiertnia4 and E. Szyfner1

1AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, 30-059 Kraków, Poland. 2Institute of Physics of Advanced Materials, Ufa State Aviation Technical University, 450000 Ufa, Russian Federation. 3Laboratory for Mechanics of Bulk Nanomaterials, Saint Petersburg State University, Peterhof, Saint Petersburg, 198504, Russia. 4Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 30-059 Kraków, Poland

In the last years one observes a strong development of different

methods devoted to produce ultrafine materials. Equal Channel

Angular Pressing (ECAP) is one of the oldest one and it is still being

developed and examined. In the present work the properties of

titanium grade 2, deformed at 3000 C by ECAP process, are studied.

Polycrystalline titanium has many technological applications in

aerospace and transport industries as well as in bio-engineering,

therefore it is a subject of intense research. Texture development

and selected microstructure parameters of titanium after

deformation (four and eight ECAP passes - route C) and after

recrystallization were studied using electron backscatter diffraction

(EBSD) technique. Also, mechanical properties, like microhardness

and strain-stress relations, were examined. After ECAP deformation

the material properties were strongly modified. The grain size

decreased radically (and more fragmented grains were formed), the

defect density increased, the proportion of low and high angle

boundaries changed and material hardness as well as mechanical

strength increased noticeably. Also, a characteristic texture was

formed. Generally, it was noted that major modifications of material

characteristics appeared after initial four ECAP passes. The

consecutive four ECAP passes led already to much smaller

modifications of material properties.

A-4 Texture, microstructure and mechanical properties evolution in Fe-(x=36 and 48 wt.%) Ni alloy after accumulative roll bonding S. Boudekhani-Abbas1, K. Tirsatine1, H. Azzeddine1,2, B. Alili1, A.L. Helbert3, F. Brisset3, T. Baudin3, D. Bradai1 1Faculty of Physics, University of Sciences and Technology Houari Boumediene, BP 32 El-Alia, 16111, Algiers, Algeria. 2 Departments of Physics, University of M’sila, Algeria. 3 ICMMO, SP2M, Univ. Paris-Sud, Université Paris-Saclay, UMR CNRS 8182, 91405 Orsay Cedex, France

ABSTRACTS POSTERS A 121

Up to now, among severe plastic deformation (SPD) techniques, only

accumulative roll bonding (ARB) processing has a great potential to

be adapted to the industry in order to produce Ultra-Fine Grain (UFG)

materials in the geometry of large sheets due to its possibility as

continuous process. Severe plastic deformation processing can lead

to significant changes in crystallographic texture compared to the

conventional ones such as compression or rolling. Texture developed

after ARB processing is generally characterized by rolling-type

components at the mid-thickness and shear-type components near

the surface. However, there is a strong lack of studies on the effect of

some special parameters such as deformation temperature, sample

preparation or solute content on texture.

The aim of the present work is to investigate the effect of solute

content on the texture, microstructure and mechanical properties

evolution after severe plastic deformation of a Fe-x(x=36 and 48

wt.%) Ni alloy by ARB processing.

The EBSD maps show a substantial grain refinement, more or less the

same for both alloys. Grains are of elongated shape and the grain

aspect ratio (defined as the ratio of the maximum grain distance to

the minimum one) reached a value near 2.5. Both samples exhibit a

different texture evolution upon straining. The Fe-48Ni (wt.%) alloy,

with a quasi-random initial texture, developed a Rotated-cube

component after 1 to 3 cycles and subsequently a Copper component

dominated after 6 cycles. However, the Fe-36Ni (wt.%) alloy, with a

strong Cube initial texture, developed a Brass component (after 3

cycles) then a Rotated-Cube component (5 cycles) and finally a

Copper-type texture after 6 cycles. The microhardness of both alloys

shows the same trends up to 6 cycles. That of Fe-48Ni (wt.%) alloy is

somewhat higher than that of Fe-36Ni (wt.%) alloy by 10% beyond the

first cycle. The effect of solute content is mainly discussed in term of

stacking fault energy.

A-5 Characterization of Fe-Co soft ferromagnetic alloys processed by laser engineered net shaping (LENS) Andrew B. Kustas, Kyle L. Johnson, Shaun R. Whetten, Dave M. Keicher, Mark A. Rodriguez, Daryl J. Dagel, Joseph R. Michael, Nicolas Argibay, Don F. Susan Materials Science and Engineering Center, Sandia National Laboratories, Albuquerque, NM, 87123

Fe-Co alloys possess favorable magnetic properties for

electromagnetic applications. However, poor workability caused by

atomic ordering can lead to cracking during conventional processing.

In this study, we explore an innovative solidification-based

processing approach to produce bulk forms of Fe-Co alloys using

Laser Engineered Net Shaping (LENS). As model materials,

equiatomic Fe-Co and Fe-Co-1.5V alloys are explored.

Microstructure of LENS specimens are characterized in terms of

grain size, crystallographic texture, and degree of atomic ordering.

Preliminary mechanical and magnetic properties are also discussed.

Sandia National Laboratories is a multi-mission laboratory managed

and operated by National Technology and Engineering Solutions of

Sandia, LLC., a wholly owned subsidiary of Honeywell International,

Inc., for the U.S. Department of Energy’s National Nuclear Security

Administration under contract DE-NA-0003525

A-6 directionally solidified non-modulated Ni54Mn24Ga22 alloys in a gradient magnetic field Long Houa, Yanchao Daia, Zongbin Lib, Yikun Zhanga, Zhongming Rena, Xi Lia,* aState Key Laboratory of Advanced Special Steels, Shanghai University, Shanghai 200072, China bKey Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China

The microstructural feature of the non-modulated martensite in

Ni54Mn24Ga22 alloys directionally solidified under the magnetic field

has been investigated based on electronic backscatter diffraction

(EBSD) measurements. The results show that the application of

magnetic field promoted the formation of [001]M orientation along

the growth direction, in contrast to dominant [110]M orientation

without magnetic field. By considering the Schmid factors, the

influence of the magnetic force due to the magnetic field gradient

on the variant selection was further analyzed. It is suggested that

magnetic force derived from magnetic gradient could be employed

for the microstructure control in Ni-Mn-Ga alloys.

ABSTRACTS POSTERS B 122

Symposium B: Misorientation Textures at Grain Boundaries and Interfaces Symposium Chairs:

Dr. Eric Homer, Department of Mechanical Engineering, Brigham Young University

Dr. Srikanth Patala, Department of Materials Science and Engineering, North Carolina State University

B-1 Obtaining 5D Grain Boundary Character from Surface EBSD using Band Intensity Profiles A. Amalaraj, J. Christensen, O.K. Johnson, E.R. Homer, D.T. Fullwood Brigham Young University, Provo, USA.

Grain boundary (GB) character strongly affects behavior of

materials. Hence, characterizing the full GB character is critical for

informing and validating material models. Surface EBSD typically

reveals only 4 of the 5 GB characteristics (relative orientation of the

grains and trace). To obtain the GB inclination, serial sectioning

(often destructive in nature) is usually performed. Here, a new non-

destructive approach is taken at determining the inclination of a GB.

If a line scan is taken across a GB, the rate of transition from the

EBSD pattern of one grain to the pattern of the second, relates to

the shape of the interaction volume, and the geometry of the GB;

more specifically, the inclination angle of the grain boundary with

respect to the scan’s path. The intensity of a given band in an EBSD

pattern is readily measured from the Hough transform of the

pattern, and provides an indication of the number of electrons

impacting the phosphor, that were emitted from a given grain. The

height of the Hough peak, for bands not shared by both grains, will

taper off as the GB is approached and crossed. The summed and

normalized intensity of the dominant bands within a grain is tracked

to provide a curve that reflects electron contribution to the EBSD

pattern from a given grain. This curve is compared with a library of

theoretical curves, arrived at via Monte Carlo modeling of electron

interactions in the area of all possible geometrical GB configurations.

The best-fit curve indicates the GB inclination. The method is

validated using GBs of annealing twins in nickel.

B-2 Effect of grain boundary engineering on the corrosion behavior of Hastelloy C-276 J. Vijay Bharadwaj1, B. Shakthipriya1 and V. Subramanya Sarma1 1Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, INDIA.

Ni base superalloys which have excellent aqueous and hot corrosion

resistance are widely used in petrochemical and other chemical

industries are subject to highly corrosive environments at elevated

temperatures in service. The damage during service is mostly due to

degradation mechanisms like intergranular corrosion, sensitization

and hot corrosion. Grain boundary engineering (GBE) (which works

on the idea of altering the distribution, nature and inter-connectivity

of grain boundary network) is an attractive approach to improve the

resistance to intergranular damage of a polycrystalline materials.

GBE microstructure is usually achieved through thermomechanical

processing involving strain-annealing or strain-recrystallization [1].

In the present study, GBE microstructure was developed in Hastelloy

C-276 (a Ni based superalloy) with a nominal composition of 58%

Ni, 16% Cr, 6% Fe, 11% Mo, 1.2% C, 0.5% V, 0.16% Si, 0.7% Co and

0.2% P through thermomechanical processing. The starting material

consisted of 53% of coincident site lattice (CSL) boundaries and a

grain size of 11 µm. The connectivity of the grain boundaries was

characterized by triple junction analysis with focus on junctions

with 2 or 3 CSL segments (labelled J2 and J3). Thermomechanical

processing involving strain annealing was imposed to achieve GBE

microstructure which increased the CSL boundary fraction to 68%.

Corrosion in oxidizing, reducing and chloride ion atmospheres was

assessed after the GBE treatment via potentiodynamic and

electrochemical impedance tests. A decrease in corrosion rate was

observed in the GBE sample as compared to the initial material

under similar conditions. The presence of carbon and chromium

makes this alloy susceptible to sensitization. The effect of GBE

treatment on sensitization was evaluated by double-loop

electrochemical potentiodynamic reactivation test. The increase in

(J2 + J3) type junctions in the GBE microstructure is expected to

reflect as increase the resistance to sensitization also. The results of

the above tests will be presented in the poster.

[1] V. Randle and G. Owen, Acta Mater. (2006), 54, pp. 1777–1783.

B-3 Microcrack Initiation and its Propagation in Cu metal films on a flexible PI substrate during cyclic-bend testing Atanu Bag, Ki-Seong Park and Shi-Hoon Choi Department of Printed Electronics Engineering, Sunchon National University, Suncheon Jeonnam, Republic of Korea

Cyclic-bend testing of a flexible copper clad laminate (FCCL) was

conducted to investigate microcrack initiation and its propagation in

electroplated Cu metal films on a flexible polyimide (PI) substrate.

During the cyclic-bend testing process, a zigzag pattern of

microcracks was developed perpendicular to the loading direction.

Electron backscattered diffraction (EBSD) was used to perform the

crystallographic orientation mappings of un-deformed (i.e. as-

received) and deformed Cu metal films on the surface planes

following different bending cycles. EBSD analysis revealed an

intergranular type of propagation that was predominant during the

cyclic-bend testing. Most of the microcracks were propagated along

the high angle grain boundaries (HAGBs) instead of the twin

boundaries (TBs). EBSD analysis also revealed that microcracks

tended to propagate into the HAGBs of neighboring grains with a

high Schmid factor (SF).

ABSTRACTS POSTERS C 123

Symposium C: Texture and Microstructure Characterization Symposium Chairs:

Dr. Irene Beyerlein, Department of Mechanical Engineering, University of California, Santa Barbara

Dr. Mukul Kumar, Lawrence Livermore National Laboratory

C-1 Texture Analysis using High Energy Material Science Beam Line (HEMS)@Petra III/Hasylab-Hamburg H.-G. Brokmeier1, Z.Y. Zhong2, M.Z. Salih1, N. Al-Hamdany1, S. Sanamar1, X. Zhou1, R. Bolmaro3, N. Schell4 1Inst. of Materials Science and Engineering, TU Clausthal, Clausthal-Zellerfeld, Germany. 2Chinese Academy of Applied Physics, Mianyang, PR China,3 Inst. de Fisica Rosario, IFIR/CONICET, Rosario, Argentina,4 Helmholtz-Zentrum Geesthacht, GEMS-Outstation DESY, Hamburg, Germany

The high-energy materials science (HEMS) beamline of the

Helmholtz-Zentrum Geesthacht (HZG) is part of the Max von Laue

Hall at Petra III storage ring. An energy range between 30 to 200 keV

is available for diffraction and imaging. While DESY runs one hutch

for hard X-ray experiments, two hutches and the side station were

operated by HZG mainly for engineering materials science

applications. Orientation analysis can be done with a conventional

set up for pole figure measurement including test rig and furnace as

well as with grain mapping obtaining 3DXRD information. The

present contribution deals with conventional pole figure

measurement.

Due to the great advantages of high energy synchrotron radiation

with excellent brilliance and high penetration power pole figure

measurements were carried out measuring texture gradients with a

typical beam size of 100µm x 100µm. Examples of texture gradients

in tubes, severe plastic deformed material, welds and finished

products will be presented. Compared to other methods, pole figure

measurement by synchrotron radiation is fast with excellent

counting statistics, so that ideal conditions for in situ studies exist.

Texture evolution under applied load, compression as well as

tension, or under annealing gives perfect results. Experiments at

different Mg-alloys, shape memory alloys, Al-alloys and Ti-alloys

have been carried out.

Disadvantages of synchrotron radiation are the long elliptical shape

of the pole figure window, the small gauge volume and the extreme

parallel beam. Problems can arise in case of un-sufficient grain

statistics and in some case of inhomogeneous textures distributions.

Means in all cases in which the texture changes during pole figure

measurement.

[1] H.-G. Brokmeier and Sang Bong Yi: Texture and Texture Analysis in Engineering Materials, In: Neutrons and Synchrotron Radiation in Engineering Materials Science, W. Reimers, A. Pyzalla, A. Schreyer, H. Clemens (eds.), Wiley VCH Verlag, Weinheim, 2008, pp.57-77.

C-2 Comparison of preferred orientation of austenite and ferrite phases of duplex steel with rolled single phase austenitic and ferritic steel J. Capek1, M. Cernik2 and N. Ganev1 1Czech Technical University in Prague, Prague, Czech Republic.

2U. S. Steel Kosice, Kosice, Slovakia.

The preferred orientation plays an important role in the various

branches of industry. Preferred orientation result in changing of

material properties depending on the significant direction [1].

In this contribution, the behavior of three type of steel after rolling

were investigated. Particular phases of duplex steel have different

mechanical and thermal properties [2]. Due to their mutual

influence during plastic deformation, it is possible to suppose the

differences between preferred orientations of austenite and ferrite

phases of duplex steel with single-phase austenitic and ferritic steel.

For this reason, the preferred orientation of austenite and ferrite

phases of rolled 1.4470 duplex steel with rolled single phase 1.4301

austenitic and 1.4021 ferritic steel were compared. The 0–50%

reductions of rolled steel plates were selected. Mainly, the strength

and type of preferred orientation in relation to reduction and

material were compared. Moreover, preferred orientation was

investigated by X-ray diffraction and electron back-scattered

diffraction (EBSD).

[1] H. Hu (1974) Texture. 1, 233–258. [2] R. Dakhlaoui, Ch. Braham & A. Baczmański (2007) Mater. Sci.

Eng.: A. 444, 6–17.

C-3 Quantitative Fiber Diffraction: from polymers to composites L. Lutterotti, L. Fambri and M. Bortolotti Department of Industrial Engineering, University of Trento, Trento, Italy.

Fiber diffraction is a specific technique aimed at measuring the

strong texture of polymers or inorganic fibers using an X-ray

transmission setup and a 2D detector. The obtained single shot

image is then analyzed qualitatively to identify the main texture

components from the strong diffraction spots. In this work we aim

to show how the combination of this experimental technique with

the adoption of the standard components inside the Rietveld

Texture Analysis (RTA) [1] can provide a quantification of the sharp

orientation distribution function. With this method, we can follow

the texture evolution of polypropylene or nylon fibers, before and

after thermal and mechanical treatment, quantifying the polymeric

chains dispersion with high accuracy. A more complex case is

represented by the addition of a stiffener like a Smectite or a

Kaolinite to a polymer fiber. In the case of Kaolinite, the modeling

inside the Rietveld is further complicated by the modulated planar

disorder typical of this clay mineral. We will show how the adoption

of a modified single layer approach [2], to account for the

modulated disorder, will help obtaining at once, the full texture of

both phases as well as the strained and highly defective structure of

the Kaolinite. This helps understanding the actual degree of

intercalation inside the fiber to further optimize the composite.

ABSTRACTS POSTERS C 124

The only filtered radiation, used in this experimental setup,

represented an additional problem as relatively strong spots are

visible in the diffraction images due to the sharp texture and

residual Bremsstrahlung. The adoption of the Ebel tube description

[3] is sufficient for the modeling of these extra spots and to solve

elegantly the problem. This opens the question if it would be more

efficient to use non monochromatic radiation, as in a true Laue

camera, to analyze this kind of sharp textures, that make fibers

closer to single crystals than to polycrystalline materials.

[1] L. Lutterotti, M. Bortolotti, G. Ischia, I. Lonardelli and H. -R. Wenk (1997) Z. Kristallogr. Suppl. 26, 125.

[2] L. Lutterotti, M. Voltolini, H. -R. Wenk, K. Bandyopadhyay and T. Vanorio (2010) Am. Mineralogist 95, 98.

[3] H. Ebel (1999) X-ray Spectrometry 28, 255.

C-4 Practical applications of nondestructive texture measurement methods M. Sepsi, M. Benke and V. Mertinger University of Miskolc, Miskolc, Hungary.

The present poster introduces practical applications of new, sample

cutting-free texture measurement methods developed for

centerless X-ray diffractometers. The possibilities offered by the

techniques are shown through practical implementations of the

methods from the field of metal forming, mineralogy and

archaeometry using a certain type of centerless X-ray

diffractometer. The execution of the measurements and the

required minor hardware modifications are also presented.

C-5 Rotation angle optimization for texture measurement using TOF neutron diffraction S. Takajo1, 2 and S. C. Vogel1 1Los Alamos National Laboratory, Los Alamos, USA. 2JFE Steel Corporation, Kurashiki, Japan.

Bulk texture measurements using pulsed neutron diffraction is a

routine application of the HIPPO (High-Pressure-Preferred

Orientation) instrument at LANSCE (Los Alamos Neutron Science

Center), but is also available at GEM/ISIS, iMATERIA/J-PARG or

NOMAD/SNS. Each of these instruments makes use of a vast

detector coverage and typically several rotations are employed to

maximize this coverage. However, to the best of our knowledge, a

tool to optimize the measurement angles to maximize the pole

figure coverage is not available. Here, we describe an approach

employing the General Mapping Tool (GMT) and ImageJ to quantify

the coverage achieved by a given combination of measurements and

rotation angles. Our approach consists of the following steps:

• Measure the detector panels’ positions in the real space and

project them on a two-dimensional plane in an equal area

projection.

• Rotate the projected image by given rotation angles.

• Superimpose all of the rotated images on the initial one and

calculate the area fraction of detector panels.

With this approach, we find that for HIPPO with 45 detector panels

around the diffraction center, covering 40°, 60°, 90°, 120° and 144°

nominal diffraction angles, the pole figure coverage is about 35%.

Through the aforementioned procedure it was clarified that the

coverage for the current standard angle set (0°, 67.5°, 90°) is 67.8%.

The coverage could be increased to 71.5% by adopting the

optimized angle set (0°, 55°, 215°). The method is applicable to any

instrument for which detector coordinates are available.

C-6 ANDES: a multi-purpose neutron diffractometer for the RA10 M.A. Vicente Alvarez1, J.R. Santisteban1, A. Beceyro1, I. Marquez1, S. Gomez, L. Monteros, S. Pincin, A. Glucksberg, A. Coleff2 1Neutron Physics Department, Centro Atómico Bariloche, CNEA. 2Mechancial Division, Centro Atómico Bariloche, CNEA

The Argentinean Atomic Energy Commission (CNEA) is building a

multi-purpose research reactor in Centro Atómico Ezeiza, 30 km

from Buenos Aires Argentina, with commissioning planned for mid

2020. The RA-10 will be an open-pool facility for radioisotope

production, materials and fuel irradiation, silicon doping and

neutron techniques applications. Associated to this last goal there is

a separate project to build the Argentinean Neutron Beams

Laboratory (LAHN), also executed by CNEA and funded by the

National Government. The first stage of LAHN project includes two

instruments of particular application in (nuclear) materials research

and development. One of them is ANDES (Advanced Neutron

Diffractometer for Engineering and Science), a multi-purpose

neutron diffractometer for materials science and engineering

applications, able to perform a variety of analysis, both on intact

objects and on small samples. The techniques available include

strain scanning, texture measurement, and high intensity powder

diffraction on a variety of environments. The development of this

instrument is supported in 4 main areas: shielding design,

mechanical engineering design, neutron optics and automation and

control. In this work we present the advances in the conceptual

design of the instrument.

C-7 Progress on the Development of Texture Analysis Capabilities at the HFIR and SNS at ORNL C.M. Fancher1, J. Bunn1, J. Einhorn2, C. Hoffmann, M.D. Frontzek, and E.A. Payzant1 1Oak Ridge National Laboratory, Oak Ridge, USA. 2University of Virginia, Charlottesville, USA.

Knowledge of the crystallographic preferred orientation of a

polycrystalline material provides critical information needed to both

predict how the material will behave in service, and understand how

and why the material failed in operation. While EBSD and X-ray

techniques are routinely used to quantify texture, these approaches

are surface sensitive. The obtained surface information is not always

representative of the bulk. In contrast, the high penetration nature

of neutrons make them ideal for investigating bulk textures. HIPPO

had served the scientific community since the early 2000s. However,

the loss of the user program at the Lujan center has severely

constrained access to HIPPO. While not specifically designed for

texture analysis, instruments at the HFIR and SNS at ORNL are well

suited to address the needs of the scientific community. This poster

will present recent work on quantifying crystallographic textures in

materials using various instruments at the HFIR and SNS at ORNL.

For example, work at HB2B at the HFIR on additively manufactured

718 Inconel has demonstrated that the processing parameters can

ABSTRACTS POSTERS C 125

be optimized to tune the grain morphology from equiaxed to

columnar, while preserving a 100 fiber texture along the build

direction. A rolled aluminum test sample is being used to develop,

and demonstrate capabilities at NOMAD and TOPAZ at the SNS, and

WAND at the HFIR.

ABSTRACTS POSTERS D 126

Symposium D: Deformation Textures Session: Titanium

Symposium Chairs:

Professor Chadwick Sinclair, Department of Materials Engineering, University of British Columbia

Professor Warren Poole, Department of Materials Engineering, University of British Columbia

Dr. Samantha Daly, Department of Mechanical Engineering, University of California, Santa Barbara

D-1 Refining Statistical Magnesium Twinning Models via Machine Learning A.D. Orme, D.T. Fullwood, I. Chelladurai, C. Giraud-Carrier, T. Colton Brigham Young University, Provo, USA.

Various statistical and probabilistic models have been created to

predict twin events, and related texture evolution, using orientation-

based attributes of magnesium alloy AZ31. Recent work done at

BYU suggests that machine learning algorithms can confirm assumed

correlations, and uncover further details of linkages between

microstructure and twin activity. The machine learning results may

also be considered a predictive model, in and of themselves [1]. This

project uses the results of machine learning models to confirm

whether the statistical models consider all the important factors

that influence deformation behavior. The results of this study will

further establish machine learning as a valuable tool in the study of

material behavior and will propose revisions to current models to

yield them more accurate in future predictions.

[1] A.D. Orme, I. Chelladurai, T.M. Rampton, D.T. Fullwood, A. Khosravani, M.P. Miles, R.K. Mishra (2016) Com Mat Sci. 124, 353-363.

D-2 Simulation for texture formation of both face-centered-cubic metals and body-centered-cubic ones based on rotational symmetry among X[100],Y[010] and Z[001] principal axes H. Masui Teikyo University, Utsunomiya, Japan

The principal axes of X[100], Y[010] and Z[001] are perpendicular to

each other as the three orbits of {±𝑋}, {±𝑌} and {±𝑍} by a

rotational symmetry of mathematical group theory in such way that

component X is not related to Y or Z one another whichever. There is

a conservation quantity in the symmetry. As Taylor proved, crystal

rotates so that slips occurs associating themselves with the

minimum total slip amount.1) The minimum total slip amount in

crystal by Taylor corresponds to both the conservation quantity in

the rotational symmetry of cubic crystal and even Taylor factor M

value itself of the material. It will be demonstrated in this study that

these approaches are useful for both face centered cubic (fcc) metal

and body centered cubic (bcc) one.

1. In fcc metal, distributions in 3D ODF coordinates for Taylor factor

M value i.e. the minimum total slip amount under cold rolling was

calculated based on Taylor’s formidable restriction rule of the five

slips.1) Main results are as follows. In fcc metal, orientation at onset

(minimum) of M value shows the cube {100}<001> and M value

increases gradually {100}<001>→ {100}<016>→{100}<013>→

{100}<012> →{100}<023>→{100}<0,9,11> with decrease of φ1 or

{100}<001>→ {016}<100> →{013}<100>→{0,6,13}<100> with

increase of φ2, most of which were experimentally reported as

indiscrete recrystallized orientations with lowest dislocation density

named the cluster composed of cube and cube-family in fcc metal.

2. In bcc metal, an intersection of two kinds of {110} planes from

the three ones composed of {110}, {101} and {011} is chosen.

Based on the rotational symmetry of the principal axes of X[100],

Y[010] and Z[001] ,72 possible combinations of the five slips on

{110} planes based on Taylor’s formidable restriction rule of the five

slips are calculated among three kinds of intersections of

two {110} planes on ⟨111⟩ direction in bcc metal. Crystal rotation is

carried out by only one solution among the 72 by the minimum total

slip amount at every strain and simulates properly lengthy of

accumulated researcher’s experimental results such as the three

stable orientations of bcc metal in rolling {112}⟨110⟩,

{11 11 8}⟨4 4 11⟩ and {100}⟨011⟩.

[1] G.I. Taylor (1938) J. Inst.Metals 62,307.

D-3 Texture Changes of Electromagnetic Ferritic Stainless Steels by Compressive Deformation at High temperatures Y. Onuki1, S. Sato1, M. Uchida1, T. Naruse2, Y. Kim2, T. Ebata2, S. Fujieda3 and S. Suzuki3 1Ibaraki University, Ibaraki, Japan. 2Tohoku Steel Co., Ltd., Miyagi, Japan. 3Tohoku University, Sendai, Japan.

Precipitation-hardened ferritic stainless steels are used for

electromagnetic actuators of engines, as these steels reveal the high

strength and soft magnetic properties. The hardening of these

ferritic stainless steels occurs by formation of nanoscale precipitates

of NiAl in during aging after solution treatment. Furthermore, it is

required to control the texture of these steels, since it is known that

the soft magnetic properties are obtained in the ferritic steels with

<100> fiber texture. However, texture control of the ferritic stainless

steels has not been attempted so far. In this study, the texture

change in a ferritic stainless steel by deformation at high

temperatures. As it has been shown that the texture of ferritic Fe-Si

alloys is significantly changed by deformation conditions such as

temperature and strain rate [1], the compressive deformation

processes were applied to the texture control of the present

stainless steels.

Samples used were a ferritic steel of Fe-14.5Cr-3Ni-2Mo-1Al-1Si (in

mass%). The specimen for uniaxial compression deformation test

was a cylinder of φ10 x H15mm. They were compressed under

different strain rates at high temperatures between 973 and 1073 K.

The microstructure and texture of the deformed sample were

characterized by analyzing the cross section of the cylindrical

samples using electron backscatter diffraction (EBSD). The volume

ABSTRACTS POSTERS D 127

fractions of <100> and <111> texture components in the sample

were mainly investigated in this work.

The texture analysis results by EBSD showed that the fraction of

<100> texture component increases with decreasing strain rate, and

reveals the maximum in the samples deformed at the strain rate of

5x10-4s-1.

The dependences of microstructure and texture on the deformation

condition seen in the current study is similar to what observed in the

previous studies [1, 2]. Namely, lower density of small angle grain

boundary and higher fraction of <100> oriented region are achieved

with lower strain rate. This suggests the activation of PDGG

(preferential dynamic grain growth). The PDGG is achieved by the

strain-induced grain boundary migration due to the difference of

stored energies between different crystal orientations. Since <100>

has lower Taylor factor than <111>, another deformation texture

component during uniaxial deformation, lower dislocation density in

<001> than in <111> is expected. Therefore, it can be concluded that

<100> oriented grains expands by consuming <111> oriented grains

so that the total stored energy in the bulk is reduced. The current

result indicates that the PDGG can be applied as the texture

controlling mechanism not only in binary or ternary alloys but also in

practical alloy steels including various elements.

[1] Y. Onuki, R. Hongo, K. Okayasu & H. Fukutomi (2013) Acta Mater., 61, 1294.

[2] Y. Onuki, S. Fujieda, S. Suzuki & H. Fukutomi (2017) ISIJ Inter., 57, in press.

D-4 Texture evolution of low carbon steel wires resulted from prior drawing process Athanasios Vazdirvanidis1, George Pantazopoulos1, Marianna Katsivarda2, Avraam Mastorakis3 1ELKEME, Hellenic Research Centre for Metals S.A, 2National Technical University of Athens (N.T.U.A.) - School of Mining & Metallurgical Engineering, 3SIDENOR S.A.

Control of the microstructure of low carbon steel wires is important

in attaining the desired mechanical and formability properties in the

final product. In this frame, ferrite grains size and morphology as

well as texture characteristics play an important role. These

parameters are simultaneously affected by the cross-section

reduction process and the amount of the imposed cold work as well

as the final recrystallization annealing treatment. Examination of

their evolution in the successive wire/rod drawing steps is therefore

considered necessary for understanding and improving the

manufacturing process. In this paper, the microstructure properties

of Ø5.5 - Ø1.5 mm steel wires are examined by optical, scanning

electron microscopy and electron backscatter diffraction. Results

include quantification of grain morphology characteristics, texture

components and discussion, interpretation together with the

evolution of mechanical properties.

D-5 The effect of damping capacity on twinned AZ31 magnesium alloy after heat treatment J.H. Kwak1, J.H. Choi1 C.Y. Kang1 and K.H. Kim1 1Pukyong National University, Busan, Republic of Korea.

The damping capacity of magnesium and its alloys were influenced

by the dislocation mechanism associated with dislocation density,

crystal orientation and grain size. The deformed material which

having a low damping capacity was improved due to heat treatment

by decreasing of dislocation density and increasing of grain size.

However, in this study, decrement of damping capacity was shown

in case of annealed specimen at 623K for 30minutes compared with

before heat treatment despite increasing tendency of damping

capacity. It is expected that the other factor is contributed to

damping capacity. The tensile twin and crystal orientation were

changed by recrystallization in all specimens. It was investigated that

the effect of crystal orientation and twin on damping capacity after

heat treatment. In order to investigate these effects, AZ31

Magnesium alloy was rolled at 673K with rolling reduction of 10%

and 50%, respectively. Damping capacity test specimens were

machined out from rolled plate with perpendicular to the Normal

direction and annealed at various heat treatment conditions. Then,

damping capacity was measured by using internal friction

measurement machine, and microstructure was examined by using

optical microscopy. Texture measurement including of XRD and

EBSD was carried out on damping specimens in order to analyze

crystal orientation distribution. In 50% rolled specimen, larger

fraction of deformation twin was observed than 10% rolled

specimen. The damping capacity of 50% rolled specimen showed

higher value than that of 10% rolled specimen. At the beginning of

the heat treatment, damping capacity was affected by residual twin

fraction, but twin fraction should not affect damping capacity due to

recrystallization with increasing of heat treatment time.

D-6 Texture formation behavior during high-temperature deformation in M1 magnesium alloy K.J. Lee, M.S. Park, J.H Choi and K.H Kim Pukyong National University, Busan, Republic of Korea.

The interest in using lightweight materials in automotive industries

has been recently growing due to reducing weight, and especially

magnesium and its alloy have been paid attention as lightweight

materials because of low density and high specific strength. In

generally, however, magnesium alloys formed a strong basal texture

which affects on mechanical property during high temperature

deformation. Thus, understanding the behavior of texture formation

in high temperature is important for improving formability. Many

researchers found that deformation condition was an important

factor in order to texture control on AZ system magnesium alloy. In

case of M1 magnesium alloy has been investigated in texture

formation resulting from grain size manipulation by precipitation,

but there seem no studies on the texture development during high

temperature on M1 magnesium alloy by deformation condition. In

this study, microstructure evolution and texture formation behavior

is investigated under various deformation conditions in M1

magnesium alloy. In order to make the same initial conditions, M1

magnesium ingot was rolled at 673 K with a rolling reduction of 30%.

Uniaxial compression tests specimens were machined in such a way

that the compression plane was parallel to the rolling plane, and

subsequently annealed at 823 K for 1h. Uniaxial compression tests

were carried out at 723 K under a strain rate ranging from 5.0x10-4s-1

ABSTRACTS POSTERS D 128

to 5.0x10-2s-1 up to a strain of -1.0. EBSD measurement was

performed for observation of crystal orientation distribution. As a

result, occurrence of the dynamic recrystallization and formation of

fiber texture was confirmed in the experimental conditions. The

grain distribution is heterogeneous in all case of the specimens. The

position of maximum axis density of the texture and its intensity

were varied depending on deformation conditions.

D-7 Deformation Behavior of Commercially Pure Titanium (Grade-2) under Uniaxial Compression Devesh Kumar Chouhan, Sudeep Kumar Sahoo, Somjeet Biswas Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, West Bengal-721301, India

Commercially pure titanium (CP-Ti) and its alloys are of great

importance in aerospace, permanent bio-implant, chemical and

automobile industries. This is due to its excellent corrosion

resistance and high strength to density ratio. Conventional thermo-

mechanical processes and in specific cases, severe plastic

deformation techniques are used to enhance their mechanical

properties by altering microstructure and crystallographic texture.

CP-Ti has hexagonal close packed (hcp) structure below 1155K.

During plastic deformation; basal<a>, prismatic<a> and pyramidal

{<a> and <c+a>} slip systems could be activated. However, during

room temperature, a major part of the deformation consists of

twins. In this work, deformation behavior of CP-Ti at low strain by

uniaxial compression is studied. The grain refinement mechanism,

evolution of texture and the associated twins and CSL boundaries

are investigated.

ABSTRACTS POSTERS N 129

Symposium N: Mathematical, Numerical and Statistical Methods of Texture Analysis Symposium Chair:

Dr. Oliver Johnson, Department of Mechanical Engineering, Brigham Young University

N-1 Texture Visualization Using Neo-Eulerian Rotation Representations P.G. Callahan1, M. Echlin1, T.M. Pollock1, S. Singh2 and M. De Graef2 1UC Santa Barbara, Santa Barbara, USA. 2Carnegie Mellon University, Pittsburgh, USA.

The texture of a polycrystalline material is usually expressed in

terms of the Bunge Euler angles; an orientation distribution function

(ODF) is then visualized by means of contour plots in planar sections

through the relevant fundamental zone (FZ). With the availability of

large scale orientation data sets obtained from EBSD experiments it

has recently become feasible and useful to consider other rotation

representations, in particular the neo-Eulerian representations,

including the Rodrigues-Frank vector, the quaternion vector, the

homochoric vector, and the 3D stereographic vector. In addition,

the cubochoric representation, a new equal volume mapping of the

unit quaternion hemi-sphere onto a cube, has recently become a

useful representation, especially in the context of dictionary

indexing of EBSD patterns as well as the determination of the ODF

from pole figures via model-based iterative tomographic

reconstruction.

In this contribution, we will begin with a review of the relevant

orientation/rotation representations as well as a detailed

consideration of the graphical visualization, using 3D rendering, of

the crystallographic fundamental zones for all rotational point group

symmetries. Due to the historical importance of the Euler

representation, we will also describe how the Rodrigues-Frank

fundamental zones, which have planar boundaries due to the metric

properties of Rodrigues space, can be mapped into the primary Euler

cell. The Rodrigues FZs of the cyclic rotation groups are represented

in Euler space by prismatic volumes aligned along the 𝜑2 = −𝜑1line;

for rotational groups with multiple rotation axes, the top surface of

this prism acquires a “tented” shape which can be expressed

analytically. Connections to conventional FZ selections in Euler space

will be made, and several basic texture components (cube, Goss,

etc.) will be illustrated in both representations.

We will also apply the new 3D visualization schemes to actual

experimental textures, including a random texture in a Rene 88

alloy, cube and Goss textures in Fe-Si transformer steels, and the

texture of a two-phase alpha-beta Titanium alloy. We will describe

the basic techniques used to obtain the visualizations using open

source rendering programs, as well as a series of open source

routines that can be used to transform lists of Euler angle triplets

into any of the representations described above.

ABSTRACTS POSTERS R 130

Symposium R: Crystallization, recrystallization and growth textures Symposium Chairs:

Dr. Rodney McCabe, Los Alamos National Laboratory

Asher Leff, Department of Materials Science and Engineering, Drexel University

R-1 Recrystallization Texture Evolution of Cold Rolled and Asymmetrically Warm Rolled Austenitic Stainless Steel Sheets S. Umehara1, H. Inoue1 and J. Hamada2 1Osaka Prefecture University, Sakai, Japan. 2Nippon Steel & Sumikin Stainless Steel Corporation, Hikari, Japan.

A {111} texture leads to good deep drawability but does not

generally develop in face-centered cubic metals. One of the authors

previously succeeded in {111} recrystallization texture evolution by

cold rolling, asymmetric warm rolling and subsequent solution

treatment for Al-Mg-Si alloy sheets. In this study, rolling and

recrystallization textures of austenitic stainless steel with low

stacking fault energy have been investigated to reveal whether the

{111} texture can be formed by similar processing. Rolling texture

changes from the α-fiber texture in 70% cold rolled sheets to an

asymmetric texture on the TD axis consisting of {331}<116>-

{111}<112> by additional 40% asymmetric warm rolling, which was

conducted at 873 K using rolls with different diameters.

Correspondingly, pole density at the center of {111} pole figure

increased from 2.16 to 3.18. In addition, microstructural observation

showed that there were two kinds of shear bands inclined at about

30° and 150° to RD on the longitudinal section. One is shear bands

within grains and the other is shear bands passing through a number

of grains. Recrystallization texture after annealing also shows an

asymmetric texture on the TD axis, but consists of {431}<257>-

{331}<116> similar to the α-fiber texture. The 1173 K-1800 s

annealing decreases pole density at the center of {111} pole figure

to 0.78. The 1073 K-3600 s annealing leads to slightly higher pole

density of 1.00 at the center of {111} pole figure. In conclusion, the

rolling texture with near-{111}<112> orientation was obtained in

cold rolled and asymmetrically warm rolled austenitic stainless steel

sheets. However, the recrystallization texture changed to near-

{110}<112> orientation as a main component.

R-2 Effect of Y contents on microstructure and texture evolutions in grain-oriented silicon steel C.S. Park, H.D. Joo, K.S. Han, J.K. Kim and J.T. Park

Steel Product Ⅱ Research Group, POSCO Technical Research

Laboratories, Pohang, Korea.

The microstructure and texture evolutions with various Y contents

were investigated in grain-oriented silicon steel by optical

microscopy and electron backscattering diffraction. As increasing Y

contents, normal grain growth was inhibited during primary

recrystallization and abnormal grain growth was successfully

achieved without any precipitates such as AlN and/or MnS after

secondary recrystallization. Especially, when the Y content was more

than 0.05 wt%, the abnormally grown grains had Goss orientations

and the magnetic flux density of the sheets at 1000 A/m was higher

than 1.8 tesla. The changes of microstructure and texture evolution

are thought to be due to solute segregation of Y atoms at the grain

boundaries.

R-3 The effect of an intermediate heat treatment during thermomechanical controlled processing on recrystallization and subsequent deformation-induced ferrite transformation textures in microalloyed steels P. Gong, B.P. Wynne, W.M. Rainforth Department of Materials Science and Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, S1 3JD, UK

The evolution of texture components for two experimental 0.06 wt%

C steels; one containing 0.03 wt% Nb (Nb steel) and the second

containing both 0.03 wt% Nb and 0.02 wt% Ti (Nb-Ti steel) was

investigated following a new thermomechanical controlled process

route, comprising first deformation, rapid reheat to 1200°C and final

deformation to various strains. Typical deformation textures were

observed after first deformation for both steels. Following

subsequent reheating to 1200°C for various times, the

recrystallisation textures consisted primarily of the α-<011>//RD

texture fiber with a weak -{111}//ND texture fiber, similar to

deformation textures, indicative of the dominance of a strain-

induced boundary migration (SIBM) mechanism. The texture

components after finish deformation were different from the rough

deformation textures, with a strong α-<011>//RD texture fiber at the

beginning, and then the strong peaks move to (111)<12 1> and

(111)<1 1 2> textures due to the deformation-induced ferrite (DIF)

transformation. The effect of Ti on the recrystallisation textures and

deformation textures has also been analysed in this study. The

results illustrate that Ti significantly influences the -{111}//ND

texture fiber. Finally, the textures after deformation and

recrystallisation in the austenite were calculated based on the K-S

orientation relationship between austenite and ferrite. This allowed

the understanding of the mechanism of recrystallization between

first and finish deformation, and the deformation induced ferrite

textures during phase transformation.

ABSTRACTS POSTERS T 131

Symposium T: Transformation Textures Symposium Chair:

Dr. Michael Roach, Biomedical Materials Science, University of Mississippi Medical Center

T-1 Effect of strain-induced martensitic transformation on texture evolution in cold-rolled Co-Cr alloys S. Sato1, M. Nakagawa1, Y. Onuki2, K. Yamanaka3, M. Mori4, A. Hoshikawa2, T. Ishigaki2 and A. Chiba3 1Graduate School of Science and Engineering, Ibaraki University, Hitachi, Japan. 2Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Japan. 3Institute for Materials Research, Tohoku University, Sendai, Japan. 4Department of Materials and Environmental Engineering, National Institute of Technology, Sendai College, Natori, Japan.

Co-Cr alloys exhibit high tensile strength with good elongation and

excellent corrosion-resistance properties and hence have been used

in many biomedical uses such as stents and artificial hip joints.

However, the difficulty in plastic deformation limits the application

of the alloys. The plastic deformability of the Co-Cr alloys is

depressed by the strain-induced martensitic transformation (SIMT),

which originates from low stacking fault energy of these alloys, and

the distinct increase in dislocation density in the matrix phase. Since

these microstructural evolution accompanies with the texture

evolution, it is crucial to understand the relationship among the

SIMT, the increase in dislocations, and the texture evolution. To

characterize the evolution of the texture, SIMT, and dislocations, we

evaluated the phase fraction of the martensitic phase and

dislocation density by using time-of-flight neutron diffraction at

iMATERIA beamline in J-PARC. The cold-rolled sheets of Co-29Cr-

6Mo (CCM) and Co-20Cr-15W-10Ni (CCW) alloys were investigated

in this study. While the stacking fault energies of these Co-Cr alloys

are low enough to propagate the SIMT at room temperature, the

stacking fault energies of the CCM and CCW alloys are negative and

positive, respectively, at room temperature. Namely, the SIMT is

expected to proceed more preferentially in the CCM than the CCW

alloy. The volume fraction of martensitic phase (HCP) was

determined by Rietveld-texture analysis with the use of the MAUD

program. As expected from the stacking fault energies, the SIMT

progressed at a small rolling reduction of 10% in the CCM alloy,

whereas the volume fraction of the martensitic phase was almost

zero up to the rolling reduction of 20% in the CCW alloy and

increased rapidly from the rolling reduction of 30%. The texture of

the matrix phase (FCC) of the CCM and CCW alloys gradually

developed in a similar manner, whereas the martensitic phase had

strong texture even at small rolling reduction. This may be because

the martensitic phase formed selectively from grains with specific

crystallographic orientations. To evaluate the dislocation density,

the line-profile analysis was also carried out on the high-resolution

diffraction data obtained from the backscatter detectors. The

dislocation density of the matrix phases of the CCM and CCW alloys

increased similarly with an increase in the rolling reduction. These

microstructural characteristics suggest that the difference in

deformability between the CCM and CCW alloys originate not from

the strain hardening of the matrix phase but from the growth

behavior of the martensitic phase.

T-2 Characterization of the Factors Influencing Retained Austenite Transformation in Q&P Steels via EBSD Analysis D. Adams¹, D. Fullwood¹, J. Cramer¹, S. Irfan¹, H. Evanson¹, T. Mathis¹, S. Cluff¹, M. Miles¹, E. Homer¹, T. Brown², R. Mishra², and B. Kubic² ¹Brigham Young University, Provo, USA. ²General Motors, Warren, USA.

A recent push for more fuel-efficient vehicles by the automotive

industry has encouraged an increased focus on formable Advanced

High-Strength Steels (AHSS). These steels are of particular interest

due to their unique combination of high strength and ductility,

which allows them to provide the necessary strength to reduce

weight requirements in certain parts of an automobile. The

particular AHSS of interest in this study rely on the Transformation

Induced Plasticity (TRIP) effect, in which a minority fraction of

retained austenite (RA) grains in the steel transform to the stronger

martensite phase as the steel is plastically deformed, providing extra

ductility via the transformation event. Understanding the factors

involved in RA transformation is therefore key to being able to

optimize the microstructure of these steels. This research seeks to

increase understanding of the correlations between microstructure

and RA transformation in TRIP AHSS steels. Through in-situ tensile

tests combined with EBSD and FSD scans, local strain maps at the

micro-scale can be created and analyzed with DIC software. With

this information, it is hoped that the questions of when and why

transformation occurs and the benefits of that transformation can

be answered. Once the answers to those questions are understood,

an improved model of the transformation can be created and allow

for optimization of these advanced materials.

ABSTRACTS POSTERS W 132

Symposium W: A Celebration of the Contributions of Rudy Wenk Symposium Chairs:

Dr. Lowell Miyagi, Geology & Geophysics, University of Utah

Dr. Pamela C. Burnley, Department of Geoscience, University of Nevada, Las Vegas

Dr. Sven Vogel, Los Alamos National Laboratory

W-1 Texture and fracture anisotropy in shales deformed in a deformation DIA Jeff Gay1, Waruntorn Kanitpanyacharoen2, Michael Jugle1, Julien Gasc3-4 Tony Yu4, Yanbin Wang4, and Lowell Miyagi1 1Department of Geology and Geophysics, University of Utah, Salt Lake City, UT U.S.A. 2Department of Geology, Chulalongkorn University, Bangkok Thailand. 3Laboratoire de Géologie, École Normale Supérieure-CNRS, UMR8538, Paris France. 4Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL U.S.A.

Understanding the link between micro and macro scale properties in

earth materials has become increasingly important in geophysical

research. Texture in shales is responsible for much of the seismic

anisotropy that is observed in sedimentary basins. The interaction

between texture and facture anisotropy is critical for assessing

viability of shale as a cap rock in conventional reservoirs, as a

potential source rock for production of natural gas in

unconventional reservoirs, or as target for nuclear sequestration.

Here we deform shales to failure at high pressure and temperature

using the deformation DIA (D-DIA). The D-DIA allows the user to

separate hydrostatic and deviatoric stresses and can be used to

deform samples under high pressure and temperature in both

compression and extension. The D-DIA was originally designed to

generate pressures in excess of several GPa in order to study

deformation behavior of materials at mantle conditions. However,

since there are no conventional crustal rheology devices available at

synchrotron beamlines we use a novel polyether ether ketone

(PEEK) cell assembly to generate reduced pressures of 100-300 MPa

at temperatures of 100-200°C, conditions appropriate for moderate

to deep shales. In-situ texture development, lattice strain evolution,

failure onset, and macrostrain are measured using radial

synchrotron x-ray diffraction and radiography. Texture information

is extracted using the Rietveld method as implemented in the

software program Materials Analysis Using Diffraction (MAUD). The

use of this “low pressure” cell assembly in the D-DIA opens the

possibility to deformation experiments at crustal conditions using

synchrotron x-rays to measure in-situ texture development and

rheological properties.

W-2 In situ texture measurements at high-pressure and high temperature using double-sided laser heating in a radial diffraction diamond anvil cell at ALS beamline 12.2.2 M. Kunz1, J. Yan2, Alastair MacDowell1, Lowell Miyagi3 and H.R. Wenk4 1Lawrence Berkeley Lab, Berkeley, California. 2UC Santa Cruz, Santa Cruz, California. 3University of Utah, Salt Lake City, USA. 4UC Berkeley, Berkeley, California.

Determining the texture throughout the interior of the Earth is

important to understand seismic profiles of the Earth and to

quantify the large scale convection of the Earth’s mantle, which in

turn is linked to the motor of plate tectonics. The study of texture in

rocks and minerals at conditions of the lower mantle or even core

requires diamond anvil cells (DAC’s) as pressure device. The use of

DAC’s for in situ texture measurements was developed to a large

part by Rudy Wenk and co-workers [1-3]. The main criticism of initial

work was that experiments were performed at room temperature

and therefore were irrelevant for processes that happened in the

lower mantle. This was overcome by two approaches 1) an in situ

single-sided laser heating set up [4] co-designed by the Wenk group

and implemented at the ALS and 2) a resistively heated radial

diffraction DAC [5] at DESY. Axial temperature gradients and limited

maximal temperatures are draw-backs of these approaches A

double-sided in situ laser heating set-up based on the laser and

pyrometry optics mounted on a rotational stage was proposed at

HPCAT [6] but never implemented.

In this contribution, we present the implementation of in-situ

double-sided laser heating compatible with radial X-ray diffraction

for texture measurements at beamline 12.2.2 of the Advanced Light

Source (ALS) at Lawrence Berkeley Lab (LBL). The system builds on

the existing, newly built axial set up including peak scaling

pyrometry. Laser and imaging paths are redirected in the horizontal

plane from a 0°/180° direction to a 90°/270° setting. The 90°

redirection involves the insertion of a small periscope mirror pair

with an objective lens into the axial downstream beam path. This is

fully motorized and can be achieved remotely. The 270° beam path

on the other hand involves the removal of the upstream axial

objective lens and the manual installation of a small rig carrying 2 IR

mirrors and the objective lens. Installation and alignment is straight

forward and fast. For temperature measurement, we employ the

peak scaling method also implemented on the axial laser heating set

up. This allows recording 2-dimensional temperature maps and thus

temperature gradients in quasi real time.

Examples of in-situ texture measurements at high pressure and high

temperatures will be presented.

[1] S. Merkel, H.R. Wenk et al. (2002) J. Geoph. Res.107 (B11), 2271, doi:10.1029/2001JB000920.

[2] H.R. Wenk, S. Mathies et al. (2000) Nature 405 1044, doi:10.1038/35016558.

[3] H.R. Wenk, S. Cottaar et al. (2011) Earth Planet Sci Let 306 33, doi:10.1016/j.epsl.2011.03.021.

[4] M. Kunz, W.A. Caldwell et al. (2007) Rev. Sci. Instrum. 78, 063907, doi:10.1063/1.2749443.

[5] H-P. Liermann, S. Merkel et al (2009) Rev. Sci. Instrum. 80 104501, doi:10.1063/1.3236365.

[5] Y. Meng, G. Shen and H.K. Mao (2006) J. Phys.: Condens. Matter 18 S1097, doi:10.1088/0953-8984/18/25/S17.

ABSTRACTS POSTERS W 133

W-3 CPO patterns of an upper crustal shear zone – examples from the Lancinha Fault System, southern Brazil T. Conte1, G.C.G. Cavalcante1, L.E. Lagoeiro1, C.S. Silveira1, K.T. Pesch1, and R. Santos1. 1UFPR – Universidade Federal do Paraná, Curitiba, Brazil.

Crustal deformation processes are related to the rheological

behaviour, which is controlled by mineral constituents, temperature

and pressure conditions, as well as strain rate and fluid assistance.

Upper crustal deformation is dominated by cataclastic flow and low

temperature dislocation creep, often associated with bulging and

subgrain rotation recrystallization. The Lancinha Fault System (LFS),

located in the southern part of the Ribeira Belt, is a Neoproterozoic

dextral strike-slip shear zone trending NE, which extends over ~150

km separating the Apiaí and Curitiba terranes. The southern Ribeira

belt is limited to the north by the Paranapanema craton and to the

south by the Luís Alves craton. The Ribeira Belt was formed as a

result of the collision between the São Francisco, Congo and

Paranapanema cratons during the amalgamation of west Gondwana

at ~600 Ma. Three samples representing quartzites, S-C type schists

and mylonites that crop out along the LFS area were analysed by the

SEM-EBSD technique, and the data were processed using the Mtex

toolbox in MatLab. Thermobarometry studies suggest that these

rocks were deformed under greenschist facies conditions (~300 -

350°C). The rocks are composed mainly of quartz, feldspar,

plagioclase and mica, distributed along anastomosing cleavage

surfaces. Quartz in all samples exhibits ribbon shapes with aspect

ratios up to 7:1, subgrain boundaries, new grains formed by bulging,

and undulose extinction. Samples collected close to the LFS display

J-index ranging from 6.20 to 35.31, while the quartzite sample

located further shows a J-index of 2.85, which suggests that the CPO

(crystallographic preferred orientation) fabric strengthens close to

the shear zone, probably due to an increase in strain. A peak at 60˚ is

observed in the misorientation angle diagram of the mylonite and

the schist located close to the LSF, whereas a peak at low angle

(<10˚) occurs for the quartzite far from the shear zone. The peak at

60˚ is related to dauphiné twinning, while the low angle peak

corresponds to the formation of subgrains. The quartzite and the

schist display quartz c-axis oriented parallel to Z (pole to the

foliation) and a-axis parallel to X (stretching lineation), suggesting

the activation of the basal <a> slip system. A secondary

concentration of rhomb planes close to Z suggests that activation of

rhomb <a> also occurs during the quartzite deformation. Activation

of such slip systems is consistent with the low temperature

microstructure observed in these samples, and suggests that

dislocation creep deformation mechanisms are dominant. The CPO

fabric of the mylonite shows a strong maximum of quartz c-axes

close to X. Such c-axis orientation may be a result of oriented

growing of the quartz grains, since the mylonite microstructure is

typically of low temperature deformation associated with bulging

and subgrain rotation recrystallization, and therefore inconsistent

with the activation of high-temperature slip systems such as prism

<c>. Our results show that low-temperature deformation in shear

zones may be controlled by the dominant recrystallization

mechanism and by preferred growth of quartz. To what extent these

mechanisms depend on local conditions (fluid, strain rate, etc) is not

clear, and future work on similar shear zones should be performed

for comparison.

W-4 Microscale strain partitioning during high-temperature deformation of plagioclase: an example from gabbro-norite of the Barro Alto Complex, Brazil central C.S Silveira¹, L.E. Lagoeiro¹, G.C.G. Cavalcante¹, P.F. Barbosa², F.O. Ferreira³, T. Conte¹, R. Santos¹ M.T.F. Suita4 ¹Universidade Federal do Paraná, Curitiba, Brazil; ²Univesidade de Brasília, Brasília, Brazil;³ Universität Bayreuth, Bayreuth, Germany ; 4Universidade Federal de Ouro Preto, Ouro Preto, Brazil.

Microstructures and textural analysis are essential to evaluate

aspects related to plastic deformation in minerals of the crust,

especially for abundant minerals such as plagioclase. In this work,

we analyzed metamorphosed gabbro-norites from the mafic-layered

complex Barro Alto, with the purpose of understanding the

development of preferred orientation in plagioclase by optical and

electron microscopy associated with the EBSD technique. The Barro

Alto complex is a continental-scale feature exposed in the Brasília

Belt, which belongs to Tocantins Structural Province, Brazil Central.

This complex was formed by mafic-ultramafic layered intrusions

mylonitized and metamorphosed under granulite facies conditions.

The samples are composed of porphyroclasts of plagioclase and

diopside in a matrix dominantly composed of plagioclase,

clinopyroxene, orthopyroxene and, less commonly, amphibole and

biotite. We separated the samples in two groups according to the

matrix grain size. Group A comprises three samples with a very fine-

grained mylonitic matrix (0.03 to 0.08 mm) which wrap around

porphyroclasts. The Group B has one sample composed mainly by

medium-grained plagioclase (1 to 0.5 mm). Both groups shows

composition segregation into felsic and mafic bands, mechanical

twinning, undulose extinction and recrystallization of plagioclase

grains. In Group A, the plagioclase poles figures for {100}, {010} and

{001} show a weak texture with a low J index (2.4). In Group B, pole

figures exhibit maximum in {100} parallel to X direction and {010}

parallel to Z direction. The strongest texture for the pole figures is

confirmed by the high J index (15.33). The microstructure and

texture analyses suggest that different deformation mechanisms

were active in each group. The weak texture observed in Group A

may be a result of diffusive processes in fine-grained aggregates. On

the other hand, in coarser-grained domains dislocation creep may

dominate, which led to the development of stronger texture. In

Group B the principal mechanism is dislocation creep controlled by

the [100](010) slip system. These results are consistent with high-

grade deformation conditions of the Barro Alto Complex.

Differences in grain size suggests a strong partitioning of

deformation between diffusive processes (grain size sensitive

mechanism) in fine grained aggregates, and dislocation creep in

large grains aggregate.

ABSTRACTS POSTERS W 134

W-5 Application of the Elasto-Viscoplastic Self Consistent (EVPSC) code to modeling texture and lattice strain evolution in periclase

F. Lin1, N. Hilairet2, S. Merkel2, J. Immoor3, H. Marquardt3, C. Tomé4 and L. Miyagi1 1Department of Geology and Geophysics, University of Utah, Salt Lake City, 84112, USA. 2Unité Matériaux et Transformations, Université Lille 1 - CNRS - ENSCL, Villeneuve d'Ascq, France. 3Bavarian Research Institute of Experimental Geochemistry and Geophysics, University Bayreuth, 95440 Bayreuth, Germany. 4Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA

Seismic anisotropy is observed in many regions of the deep earth. It

is believed that this is due to texture (crystal preferred orientation)

development as a result of plastic deformation of minerals by

dislocation glide and climb. Ferropericlase is the second most

abundant phase in the Earth’s lower mantle. Thus, understanding

the deformation mechanism of ferropericlase minerals is important

to interpret anisotropy in the Earth’s lower mantle. In this study,

deformation of a periclase was performed in the Deformation-DIA

(D-DIA) at the European Synchrotron Radiation Facility (ESRF)

beamline ID06. A polycrystalline sample was deformed at ~5.4 GPa

and ambient temperature to a total strain of ~0.37 at average strain

rates of 9.52e-6/s, 2.26e-5/s and 4.30e-5/s. Lattice strains and texture

were recorded using in-situ synchrotron x-ray diffraction. Lattice

strains were extracted using Multi-fit/Polydefix and texture

information were obtained by Rietveld texture analysis using the

software package Materials Analysis Using Diffraction (MAUD).

During deformation, lattice strains on {200} showed an increase in

strain early in deformation followed by a rapid decrease upon

continued deformation. This initial peaking of lattice strain may due

to pinning from carbon contamination introduced during sintering of

the sample prior to deformation. Lattice strains on {200} are

significantly smaller than lattice strains on {111} and {220}. Lattice

strains on {220} are slightly larger than those on {111}. Texture

development is characterized by {001} planes becoming oriented at

high angles to compression. Here we used the Elasto-Viscoplastic

Self-Consistent (EVPSC) method to simulate lattice strains and

texture evolution as a function of slip systems activities. Parameters

such as critical resolved shear stress (CRSS) for the various slip

systems, strain hardening, initial grain shape and Inclusion-Matrix

interaction assumption were modified in order to optimize the

simulation. We obtained a good fit to the experiment with dominant

{110}<1-10> slip and a parabolic strain hardening. This illustrated

the utility of EVPSC to understand deformation of materials at high

pressures.

W-6 Deformation of two-phase polycrystals under high pressures: effect of phase proportions on in-situ textures and stress partitionning in olivine + antigorite N. Hilairet1, T. Ferrand2, P. Raterron1, S. Merkel1, A. Schubnel2, J. Guignard3*, C. Langrand1, W. Crichton3 1CNRS - Université de Lille - ENSCL, 59000 Lille, France. 2CNRS - ENS, 75005 Paris, France. 3European Synchrotron Radiation Facility, 38000 Grenoble, France. *now at Observatoire Midi-Pyrenées, 31400 Toulouse, France

Serpentinization is expected to occur when fluids are released from

the dehydrating subducting slabs and migrate into shear zones and

the mantle wedge formed of peridotite. At shallow depths (15-

30km) a few percent volume serpentine can induce strain

localization and strongly textured domains in peridotite bodies.

Aggregate seismic velocities as a function of microstructure and

serpentine proportion have been investigated by several studies.

Less is known on mechanical properties and seismic velocities of

deformed peridotites containing antigorite in deeper contexts.

Antigorite and olivine both have (very) anisotropic single crystal

elastic properties, which for a mixed aggregate may result in several

types of large scale seismic velocities anisotropies in subduction

zones. These seismic velocities will be highly dependent on

deformation mechanisms and on the texture and microstructure of

the aggregate, which are expected to evolve as a function of strain

and serpentine proportion. Here we investigate the rheology and

textures of antigorite + olivine « synthetic » peridotites with varying

serpentine content (5 to 50%) at high pressure (2- 3 GPa, ca. 60-90

km depth), using the D-DIA large volume press and synchrotron

powder X-ray diffraction and imaging. The results will provide

insights on the conditions under which serpentinized peridotites

evolve in a regime dominated by the rheology of the strongest

phase (olivine) or the weakest phase (antigorite). This study will

further help refine our knowledge of the serpentinized peridotites

seismic velocities at depths, taking into account potential

deformation mechanisms variation with phase proportions.