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Research in Mechanics and Nano S&Eby
Ken P. ChongPhD, PE
Director of Mechanics & MaterialsEngineering Directorate
National Science Foundation
www.nsf.gov
National Science FoundationFY2005 Request – ($5.7B) and ’05 Increases
National Science Board
Director
Office of theInspector General
Staff Offices
Directorate forEngineering
Directorate forBiologicalSciences
Directorate forGeosciences
Directorate forComputer and
InformationScience andEngineering
Directorate forMathematicaland Physical
Sciences
Directorate forSocial,
Behavioral,and Economic
Sciences
Directorate forEducation and
HumanResources
($13.0M) $600M ($13.4M) $618M ($-167.6M) $771M
($10.3M) $472M ($15.4M) $729M ($24.0M) $1,116M ($20.9M) $225M
Polar and Antarctic Programs
($7.6) $350M
IntegrativeActivities
(MRI, STC)
($95.9) $240M
SBIR/STTR
($0.5M) $104M
NSF Engineering DirectorateFY2005 Request
Assistant Director John A. Brighton
Deputy Assistant DirectorMichael Reischman
Design,Manufacture &
Industrial InnovationDMII
Civil &Mechanical
SystemsCMS
Electrical &Communications
SystemsECS
EngineeringEducation &
CentersEEC
Bioengineering & Environmental
SystemsBES
Vasu Varadan Gary Gabriele Warren DeVries
Bruce Hamilton Ken Chong* Richard Buckius
Senior Advisor
SBIR/STTR**
Mike Roco
($10.3M) $471.8M
SBIR/STTR**
($-1.3M) $49.8M ($18.3M) $85.5M ($0.5M) $68.9M)
Chemical &TransportSystems
CTS
Chemical &TransportSystems
CTS($-1.7M) $67.2M
($-1.9M) $72.7M($0.1M) $65.9M ($-3.3M) $130.7M($0.5M) $104.1M
Kesh Narayanan
**NSF-wide program – now changed to Office of Industrial Innovation; * now Adnan Akay
NanotechnologyDefinition on
www.nano.gov/omb_nifty50.htm (2000)
Working at the atomic, molecular and supramolecular levels, in the length scale of approximately 1 – 100 nm range, in order to understand, create and use materials, devices and systems with fundamentally new properties and functions because of their small structure
NNI definition encourages new contributions that were not possible before.- novel phenomena, properties and functions at nanoscale, which are nonscalable outside of the nm domain - the ability to measure / control / manipulate matter at the nanoscale in order to change those properties and functions- integration along length scales, and fields of application
NNI FY 2006 Budget RequestTotal = $1,054 million
Infrastructure Outcomes of 2001-2005: NSF R&D Networks and User Facilities
• Network for Computational Nanotechnology (NCN)7 universities (Purdue as the central node) Nanoelectronic device simulation/modeling
• National Nanotechnology Infrastructure Network (NNIN) 13 universities with user facility Development measuring & manufacturing tools, including NEPM Education and societal implications
• Oklahoma Nano Net (EPSCoR award)
Centers: 16 Nanoscale Science and Engineering (NSEC) - 6 (2001); 2 (2003); 6 (2004); 2 (2005)1 Nanotechnology Center for Learning and Teaching (NCLT)6 new Materials Research Science and Engineering Centers (MRSEC)
Areas of investment in FY2006(Program Component Areas)
1. Fundamental Nanoscale Phenomena and Processes
2. Nanomaterials3. Nanoscale Devices and Systems4. Instrumentation Research, Metrology, and
Standards for Nanotechnology5. Nanomanufacturing6. Major Research Facilities and Instrumentation
Acquisition7. Societal Dimensions
TINSELY ODEN, CHAIR; UT-AUSTIN
POC: KEN P. CHONG, NSF
PreliminariesPurpose of the BRP:
To explore the emerging discipline of Simulation-Based Engineering Science, its major components, its importance to the nation, thechallenges and barriers to its advancement, and to recommend to the NSF and the broader community concerned with science and engineering in the United States, steps that could be taken to advance development in this discipline.
Blue Ribbon Panel:J. Tinsley Oden (Chair) - UT Austin Ted Belytschko - Northwestern
Jacob Fish - Rensselaer Polytechnic Institute Thomas J.R. Hughes - UT Austin
Chris Johnson – University of Utah David Keyes – Columbia University
Alan Laub - UCLA Linda Petzold - UCSB
David Srolovitz - Princeton Sidney Yip - MIT
MSMBBB
HomelandSecurity
HP mat’ls/devices
V&V and UQ
Mod.& Simu.
@Nanoscale
Energy&Env.
SBE
SDDDAS
Multi-Phenomena-physics-scale Systems
CRCNS
Global
Enterpr
ises
Healthcare
Mfg. Supply Chain&Transp
Simulation Software
Next Generation AlgorithmsBig
Data Visuali
zatio
n
HPC
, CI
Modern Computation
Applied Math
Engineering Sciences
Computer Science
Others
Overarching Framework for Multiscale Modeling:
atomistic → micro → meso → macro
Key: interfaces between models at different scales
Questions:
• What are the information that needs to be transferred from one model to another?
• What are the correct ways to achieve such transfer of information?
• What physical principles must be satisfied during the transfer of information or simulation results?
Need: A set of logic, mathematical, and physical rules to govern information transfer across the interfaces
JIMMY HSIA, NSF
CORE ISSUES: Challenges, Barriers and Opportunities
• Tyranny of Scales
• Verification, Validation, and Uncertainty Quantification
• Dynamic Data Driven Simulation Systems
• Sensors, Measurements, and Heterogeneous Systems
• New Vistas in Simulation Software
• Big Data and Visualization
• Next Generation Algorithms
Materials andSurface Engineering
Solid and Bio Mechanics
Nano- and Micro Mechanics
Contact mechanics, biomimeticmaterials, thin film mechanics
Nanotribology, ultra thin film behavior, AFM mechanics, nano-structured surfaces
MEMS reliability, strength,lubrication; nano-biomechanics
Multiscale modeling
Cutting edge activities are at the interfaces
Mechanics and Materials
Adv. Solid Mechanics
Micro-Mechanics
Meso-Mechanics
Macro-Mechanics
Multi-scaleMechanics
Constitutiverelations
Experimental methods
Numericalmethods
Damage mechanics
AdvancedSimulation
Temporal, spatial
Damagemechanics
Advanced Composites
Thermal stresses
Durability,performance
Simulation,modeling
Defects
Micro-Structure
Fracture,fatigue
Deformation
Theoreticalmethods
Numerical, Exptal, analytical
Interfacialmechanics
Constitutive models
Structuralstates
Simulation,modeling
Transformation, evolution
Numerical, Exptal, analytical
Multi-phenonmena
Multi-physics
Thermal, env.forces
Simulation,optimization
Numerical,
Exptal, analytical
Electronicmaterials
Wet/dry; smartmaterials
Self-healing,Self-cleaning
Adv. Composites,Bio-inspired
Durability,performance
Simulation,optimization
Analytical,theoretical
EngineeringMaterials
Numerical, Exptal, analytical
Frontiers in solid mechanics and engineering materials
Grand Challenges & The Great Payoff: Applications and Benefits of SBES
• Medicine• Homeland Security• Energy and Environment• Materials• Industrial Applications• …
NSF Press Release 06-049Supercomputer Maps One Million Atoms of a Complete Virus in
First Simulation of a Life FormVirtual virus takes 100 days on supercomputer, 35 years on a desktop
for 50ns
Credit: University of Illinois at Urbana-Champaign's Theoretical and Computational Biophysics Group.
Composites of Carbon Composites of Carbon NanotubesNanotubes (CNT)(CNT)
10
100
1000
1 10 1000.1
SpecificModulusGPa/(g/c3)
Specific Strength, GPa/(g/c3)0.2 0.5 2 5 20 50
20
50
200
500
Aluminum 2219
Baseline Material,available today
Best availableunder development
CFRP Composite
CNTFRP Composite
Single Crystalbulk material (CNT)
Emerging material, carbon nanotubes
Long-term potentialof CNT material
from NASA-larc
Predicted Weight Savings from Polymer Matrix Composites(Primary Structure and Cryogenic Fuel Tanks)
Systems Analysis Results for a Reusable Launch Vehicle (RLV)
VehicleDryWeight
1.0
Aluminum CFRPComposite
CNTFRPComposite
from NASA-larc
55 % reduction
82% reduction
EDUCATION
• 10-12 m QUANTUM MECHANICS [TB, DFT, HF…]
• 10-9 MOLECULAR DYN. [LJ…]; NANOMECHANICS;MOLECULAR BIOLOGY; BIOPHYSICS
• 10-6 ELASTICITY; PLASTICITY; DISLOCATION...
• 10-3 MECHANICS OF MATERIALS
• 10-0 STRUCTURAL ANALYSISMULTI-SCALE, MULTI-PHENOMENA ANALYSES & SIMULATIONS…____________________________________________________________TB = TIGHT BINDING METHOD; DFT = DENSITY FTNAL THEORY;HF = HATREE-FOCK APPROX.; LJ = LENNARD JONES POTENTIAL
• NSF SUMMER INSTITUTE OF NANOMECHANICS & MAT’LS, NORTHWESTERN UNIVERSITY –contact: PROF. W.K. LIU
Scales in Plasticity
discrete dislocation models classical plasticity theories
size effects: 0.1 µm – 0.1 mm
10nm 0.1µm 1µm 10µm 0.1mm 1mm
Dislocation-based plasticity theories ?
• Any continuum plasticity theories apply only above 0.1µm !
less than 0.1µm individual dislocations ⇒ plasticity
( analogy: less than 1nm individual atoms ⇒ elasticity )
Y. HUANG, UIUC
Size Effect in PlasticityTorsion of thin wires
Fleck et al., 1993
Bend of thin beams
Soboyejo et al., 2003
Al matrix with SiC particles Vf = 15%; Particle diameter:
d = 16µm and 7.5µm
Smaller is harder!
Nano-mechanics
---- A continuum theory based on the A continuum theory based on the interatomicinteratomic potentialpotential
Interatomic Potential(nonlinear, multi-body springs)
representative material point
continuum m
odeldiscre
te sy
stem
keep
ing tr
ack o
f eve
ry at
om
Molecular Dynamics Atomistic-based Continuum Theory
Y. HUANG, UIUC
Principle of AFM
SEM image of the AFM cantilever and tip.
http://www.di.com/app_notes/spmtechnology_appnotes.htm
MEASURE FORCE F = F(d)
GERDBINNIG1986 NOBELPRIZE [STM]
CHALLENGES
multi-scale
LDLM Large Deformation Laser MoireFGLM Fine Grating Laser MoireLSI Laser Speckle InterferometryDIC Digital Image Correlation
HRTEM High Resolution Transmission Electron MicroscopyCFTM Computational Fourier Transform MoireAFM Atomic Force MicroscopySEM Scanning Electron MicroscopySRES Surface Roughness Evolution Spectroscopy
Map of Deformation-Measurement Techniques
Interface Energy Limit
Interferometric Gain
of Resolution
HRTEM-CFTM
LDLM
DIC
SRES
FGLM & LSI
Field Projection Method
Equilibrium Smoothing
Field of View (Gage Length in )mSt
rain
Res
olut
ion
10 -1
10 -9
10 -8
10 -7
10 -6
10 -5
10 -4
10 -3
10 -2
10 -1
10 -2
10 -3
10 -4
10 -5
10 -6
AFM Interferometry
NSF Award No. CMS-0070057, Engineering Directorate (Program Manager: Dr. K.P. Chong & Jorn Larsen-Basse)
K.-S. Kim, Nano & Micromechanics Laboratory, Brown University
L. SUNG, NIST
BORESI AND CHONG, ELASTICITY IN ENGINEERING MECHANICS, WILEY, 2000.
NASA Langley Research CenterNanotechnology Modeling and Simulation
Qualitative Predictions Quantitative PredictionsStructuralMechanics
Molecular Assembly
Computational Materials
Computational Chemistry
Computational Mechanics
• Electrons• Nuclei• Atoms
• Molecular fragments• Bond angles• Force Fields
• Surface Interactions• Orientation• Crystal Packing• Molecular Weight• Free Volume
• Constituents• Interphase• Damage
Fiber
Matrix
Length, (m)
10-12 10-9 10-6 10-3 100
Nano MesoQuantum Micro Macro
C
C
C
CO
CO
CO
CO2
CO2
CO2
CO
WhyMultiple Temporal Scales?
Induced by Multiple
Spatial Scales
Global Scale
Component Scales Material Scales
Multiple temporal scales Single Physical Process Induced by Multiple
Physical Processes
J. FISH, RPI
Multiple Temporal Scales for Fatigue• Multiple time scales:
• Two-scale model:0; =r
ttττ ζ
ζ=
( ) ( ) , ,1, , , ; tt tζ ζ
τφ φ τ φ φ φζ
= = +x x
:ζ scaling parameter determined by load frequency and material parameters
:ζφ
0 :τ characteristic length of micro-chronological time:rt characteristic length of macro-chronological time
response fields (e.g., displacement, stress, strain, etc…)
J. FISH, RPIJ. FISH, RPI
MultiMulti--Scale MultiScale Multi--Phenomena Modeling of Phenomena Modeling of
Structure / Property / Structure / Property / FunctionFunction
10 µm
Multi-Scale Composite
Epoxy Matrix
Nanocomposite1 µm
CarbonFiber
Nanocomposite
Carb
on
Fibe
r
100 nmCarbon Nanotubes
1 nmZig-ZagArmchairAtomic Interactionsr0
Stretching 0θ
Bending
Torsionvan der Waals
1 ÅModelin
g Hierarchy – Bridging th
e Scale from Nano to
Macro
T.W. CHOU, U. DEL.
RAJIV KALIA, LSU
S:
q=scattering wave vector
RAJIV KALIA, LSU
DISCUSSIONS OF COMMON MODELING METHODS
• FIRST PRINCIPLE CALCULATIONS - TO SOLVE SCHRODINGER’S EQ. AB INITIO, e.g. HATREE- FOCK APPROX., DENSITY FUNCTIONAL THEORY,… - COMPUTIONAL INTENSIVE, O(N4)- UP TO ~ 3000 ATOMS
• MOLECULAR DYNAMICS [MD] - DETERMINISTIC, e.g. W/ LENNARD JONES POTENTIAL- MILLIONS TIMESTEPS OF INTEGRATION; TEDIOUS- UP TO ~ BILLION ATOMS FOR NANO-SECONDS
• COMBINED MD & CONTINUUM MECHANICS [CM], e.g. MAAD; LSU; BRIDGING SCALE; …- PROMISING...
Bio-inspired Mechanics and Materials
Hierarchical Structure of Human Bone• Macrostructure
– Trabecular bone– Cortical bone
• Microstructure (10 – 500 µm)– Single osteons (cortical bone)– Trabeculae (trabecular bone)
• Sub-microstructure (1 – 10 µm)– Lamellae
• Nanostructure (below 1 µm)– Collagen fibrils– Hydroxyapatite (HA) crystals– Crystal-Collagen structure
http://silver.n
I. Jasiuk, GA Tech
The Mechanical Performance of Nacre from Seashells The Mechanical Performance of Nacre from Seashells ––Superior Toughness through Microstructural DesignSuperior Toughness through Microstructural Design
H.D. Espinosa
National Science Foundation Award No. CMS-0301416 Ken Chong
MotivationsMotivations
(Wegst & Ashby 2004)
Geological Aragonite: Geological Aragonite: A brittle ceramic A brittle ceramic KKICIC=0.3 MPa.m=0.3 MPa.m1/21/2
Nacre (95 % aragonite): Nacre (95 % aragonite): A tough bioA tough bio--compositecomposite
KKICIC=8=8--10 MPa.m10 MPa.m1/21/2
• Nacre is 20-30 times tougher than aragonite
• How does the microstructure make nacre tough?
• This is still unclear (see G. Mayer in Science, 2005) but it is much sought after, because it may open the way to synthetic mimics of nacre with superior properties (biomimetics)
The microstructure of nacre
Gecko: nano-scale attachment (K. Autumn et al. 2002)
G. Huber
Mechanics of a Mosquito Bite-Design of a Bio-mimetic
Painless Needle(Supported by NSF Grant Number CMS
0402857)M. K. Ramasubramanian, PI
J.F. Tu, Co-PICharles Apperson (Entomology)
Mosquito Skin Penetration Mechanics
• Non-conservative force application for significant increase in bucking load (Beck’s Column).
• Labium provide lateral support and keep the fascicle moist and lubricated.
• The head oscillates between .5 to 5 Hz horizontally, maintaining the force application direction tangential to the fascicle, and prevent buckling.
• Increase in buckling load is sufficient for skin penetration.
What’s special about spider silk?
Material Strength Elasticity Energy to Break(N m-2) (%) (J kg-1)
Dragline Silk 4 x 109 35 1 x 105
Minor Silk 1 x 109 5 3 x 104
Flagelliform silk 1 x 109 200+ 1 x 105
KEVLAR 4 x 109 5 3 x 104
Rubber 1 x 109 600 8 x 104
Tendon 1 x 109 5 5 x 103
______________________________________________________________________TABLE 1. Various biological and manmade materials are listed with their strengths, elasticities, and energies to break. Note the over ten-fold increase in the energy to break of dragline silk compared to KEVLAR. This dramatic increase is due to the elasticity of dragline silk. Also note the differences in elasticity among dragline, flagelliform and minor ampullate silks.
Randy Lewis, et al
Defining the vision and implementation planDefining the vision and implementation plan
National Nanotechnology InitiativeNational Nanotechnology Initiative
ReportsReports
Planning with feedback after each: 5 years, 1 year, 1 month; and various levels: national/NSET, agency, program In preparation: Topical reports; new 2004:10 year vision
1999: 10-year vision
MC. Roco, 10/09/03
Worldwidebenchmark
Brochure forpublic
Societalimplications
Govtplan
Defining the vision for the second strategic plan (II)Defining the vision for the second strategic plan (II)
National Nanotechnology InitiativeNational Nanotechnology Initiative20042004
ReportsReports
2004: 10-year
vision/plan Agricultureand Food Societal
Implications2004
GovernmentPlan (annual)
Energy
Surveymanufacturing Other topical reports
on www.nano.gov 2004: Update 10 year vision, and develop strategic plan
MC Roco, 3/16/05
www.nsf.gov
chaired by J. Tinsley Oden, 2006 report on “Simulation-Based Engineering Science”: www.ices.utexas.edu/events/SBES_Final_Report.pdf. www.nsf.gov/publications/pub_summ.jsp?ods_key=sbes0506
Chong, K. P., “Research and Challenges in Nanomechanics” 90-minute Nanotechnology Webcast, ASME, Oct. 2002; archived in www.asme.org/nanowebcast
Boresi, A. P., and Chong, K. P., Elasticity in Engineering Mechanics, John Wiley, 2000
Boresi, A. P., Chong, K. P., & Saigal, S. Approximate
Solution Methods in Engineering Mechanics, Wiley, 2003.
Chong, K. P., “ Nanoscience and Engineering in Mechanics and Materials”, J. of Physics & Chemistry of Solids, 65(2004) 1501-1506, Elsevier. [No. 1 of ScienceDirect TOP25 Hottest Articles]
NSF SUMMER INSTITUTE ON NANO MECHANICS & MATERIALShttp://tam.northwestern.edu/summerinstitute/Home.htm
SUMMARY & DISCLAIMER An overview of major advances, challenges and research concerning mechanics and materials are presented. The author would like to thank his colleagues and many members of the research communities for their comments and input during the writing of this presentation.
Information on NSF initiatives, announcements and awards can be found in the NSF website: www.nsf.gov. The opinions expressed in this article are the author’s only, not necessarily those of the National Science Foundation [NSF]. Any commercial products identified are for illustrations only, do not imply any endorsement.
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