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Programme of „National Mobilization Workshop” of NENAMAT Network Faculty of Materials Science and Engineering, Warsaw University of Technology
Warsaw, 7 March 2005
Time Presentation Speaker
10:30 – 10:40 Welcome address, NENAMAT Network Prof. Tadeusz Kulik, National Co-ordinator
10:40 – 10:55 Institute of Electronic Materials Technology, Warsaw Prof. Michał Kopcewicz
10:55 – 11:05 Institute of Metrology and Measuring Systems, Warsaw University of Technology
Prof. Adam Bieńkowski
11:05 – 11:20 Institute of Physics, PAS, Warsaw Prof. Jacek Kossut, Dr. Lech T. Baczewski, Prof. Henryk Lachowicz
11:20 – 11:35 Institute of Molecular Physics, PAS, Poznań Prof. Janusz Dubowik
11:35 – 11:45 Coffee break
11:45 – 12:00 Institute of Experimental Physics, University of Białystok Prof. Andrzej Maziewski
12:00 – 12:15 Institute of Non-Ferrous Metals, Gliwice Ms. Aleksandra Kolano-Burian
12:15 – 12:30 Faculty of Non-Ferrous Metals, Academy of Science and Technology, Kraków Prof. Maria Richert
12:30 – 12:45 Institute of Low Temperature and Structure Research, PAS, Wrocław Prof. Wiesław Stręk
12:45 – 13:00 Institute of Materials Science and Engi-neering, Szczecin Univ. of Technology Prof. Zbigniew Rosłaniec
13:00 – 14:00 Lunch break
14:00 – 14:15 Institute of Materials Science and Engineering, Poznan Univ. of Technology
Dr. Izabela Szafraniak, Prof. Mieczysław Jurczyk
14:15 – 14:30 Institute of Metallurgy and Materials Science, PAS, Kraków Dr. Wojciech Maziarz
14:30 – 14:45 Institute of Engineering Materials and Biomaterials, Silesian Univ. of Technology Prof. Ryszard Nowosielski
14:45 – 15:00 Faculty of Materials Science and Engineering, Warsaw Univ. of Technology
Prof. Marcin Leonowicz, Dr. Jarosław Ferenc
15:00 – 15:15 Coffee break 15:15 – 15:30 Tele & Radio Research Institute, Warsaw Prof. Barbara Ślusarek
15:30 – 15:45 Faculty of Physics, Warsaw University of Technology Dr. Piotr Jaśkiewicz
15:45 – 16:00 Closing remarks Prof. Tadeusz Kulik
Laboratory of Mössbauer Spectroscopy Institute of Electronic Materials Technology 01-919 Warsaw, Wólczyńska Street 133, Poland
1. Research team Head of the Laboratory: Prof. dr hab. Michał Kopcewicz ([email protected]) Full-time members: Dr. eng. Agnieszka Grabias, adjunct ([email protected]) Msc. eng. Justyna Kalinowska, assistant ([email protected]) Andrzej Kowalski – inspector for radiological protection 2. Research equipment - two Mössbauer effect spectrometers (for 8 independent experiments with the 57Co sources), - Mössbauer measurements in transmission geometry and scattering geometry: conversion electron Mössbauer spectroscopy (CEMS) and conversion X-ray Mössbauer spectroscopy (CXMS), - continuous flow cryostat (Oxford Instr. CF-100) for measurements in the temperature range 4.2 – 300K in transmission geometry, - closed cycle cryostat ARS Displex DMX 20 for measurements in the temperature range 10 – 300K in transmission geometry. - furnace for measurements in the temperature range 300 –1000 K in transmission geometry, - rf magnetic field generators for use in the Mössbauer transmission measurements during the rf field exposure, - furnace for sample annealing in the temperature range 300 –1200 K in vacuum or in protective atmosphere, - specialized software for Mössbauer spectroscopy (NORMOS program). 3. Research activity - Main activity: Structure and magnetism of amorphous and nanocrystalline alloys;. - Additional research activity: - Structure and magnetic properties of metallic multilayers
revealing the giant magnetoresistance effect (Fe/Cr, Fe/Si, etc...): - swift heavy ion irradiation of amorphous alloys; - ion-beam modification of materials: (ion implantation, e.g. nitrogen in metallic Fe, boron in Fe, ion-beam mixing of metallic multilayers, e.g. Fe/Zr, Fe/Ti); - formation of amorphous materials by mechanical alloying; - investigation of cobaltites and manganites revealing the giant magnetoresistance effect; - modification of steels by pulsed plasma beams; - investigation of atmospheric aerosols; Results are published in international journals (e.g., J. Appl. Phys., J. Phys.:Condens Matter, JMMM, Hyperfine Interactions, etc.) and presented at international conferences.
Institute of Metrology and Measuring Systems
Warsaw University of Technology sw. A. Boboli 8
02-525 Warsaw, Poland tel. (+4822) 660 8551 fax. (+4822) 849 0395
LABORATORY OF MECHATRONIC PROPERTIES OF MAGNETIC MATERIALS
Activities of Laboratory of Mechatronic Properties of Magnetic Materials are focused on application of modern magnetic materials (especially nanocrystaline materials) for sensors, actuators as well as power conversion devices. Research in this Laboratory are also connected with measurements of magnetic and electric quantities as well as solving of metrological problems. The main areas of scientific and technical expertise: 1. Testing of the magnetic, magnetoelastic and magnetostrictive properties of modern
magnetic materials for applications in the area of switching-mode power supplies, sensors and high-frequency transformers In cooperation with PENTALAB we developed unique measuring system for testing of magnetic and magnetoelastic properties of materials. We also developed innovative method of application of the uniform compressive stress to the ring shaped magnetic core. As a result we can determine not only the magnetic properties of materials, but also how these properties will vary under the influence of temperature, mechanical stress or other conditions of operation. These material’s characteristics are especially important in the case of reliable components of mechatronics devices, such as switching mode power supplies or power transformers.
2. Development of magnetic sensors for measurement of magnetic, mechanical and electric quantities We have experience in development and calibration of magnetic field sensors (fluxgate sensors, hall sensors). We also developed mathematical models of such sensors. Our models as well as results of our experiments created “first in the word” possibility of determination of the simultaneous influence of the temperature and mechanical stress on the functional characteristics of fluxgate sensors.
3. Magnetoelastic sensors Our group developed the new kind of magnetoelastic stress and force sensors with the ring shaped sensing elements. Due to the application of amorphous magnetic alloys as well as ferrites as sensing cores, our sensors exhibit extremely high sensitivity, wide range of the operation temperature (up to 600 oC) as well as robustness and reliability. We also proposed unique method of heat treatment of the sensor’s core. As a result our sensors exhibit low magnetoelastic hysteresis and can be applied in the industry.
4. Testing of residual magnetization of mechanical parts of engines In cooperation with WUZETEM-Warszawa we developed methodology and equipment for testing of residual magnetization of the parts of the engines. We also developed methods for demagnetization process of these mechanical parts. As a result residual magnetization of the parts was lower than 5 Gs (0,5 mT) – accordingly to the needs of car industry
Cooperation with industry During last few years we cooperated with leading Polish and world-wide producers of electronic and mechanical devices. The most important of them are:
• WUZETEM – Warszawa, Poland Demagnetization process of mechanical parts of engines
• Magnetics – Buttler, USA Testing of magnetoelastic properties of magnetic cores for switching mode power supplies
• FERYSTER – Iłowa, Poland Testing of magnetic properties of sintered materials • POLFER – Warszawa, Poland Testing of magnetic, magnetoelastic and magnetostrictive properties of power ferrites • EPCOS – Germany Testing mechatronic properties of newly developed ferrites
We are also cooperating with foreign research groups, mainly at the Institute of Physics of the Hungarian Academy of Sciences, Institute of Physics of Slovak Academy of Sciences, Institute of Non-ferrous Metals, SYMACON GmbH and Slovak University of Technology. We have also long-term cooperation with the Industrial Research Institute for Automation and Measurements in Warsaw.
The most important equipment
• Unique measuring installation for testing of the mechatronic properties of magnetic materials • Magnetic hysteresograph Walker AMH-401 (testing of magnetic properties of materials for
frequencies up to 1 MHz) • Measuring installation for testing of the magnetostrictive properties of magnetic materials
(strain-gauge measuring technic) • Fluxmeter LakeShore 480 • Fluxgate magnetometer FG-15 • Hydraulic presses • Selective nanovoltmeters
Laboratory of Mechatronic Properties of Magnetic Materials The most important publications
1. A. Bieńkowski, R. Szewczyk “The possibility of utilizing the high permeability magnetic materials in construction of magnetoelastic stress and force sensors” Sensors and Actuators 113/3 (2004) 270-276
2. R. Szewczyk, A. Bieńkowski „Stresss dependence of sensitivity of fluxgate sensor” Sensors and Actuators 110/1-3 (2004) 232-235
3. A. Bieńkowski, R. Szewczyk “Influence of thermal treatment on magnetoelastic villari effect in Fe78Si13B9 amorphous alloy” Materials Science & Engineering A 375-377C (2004) 1024-1026
4. R. Szewczyk, A. Bieńkowski, J. Salach, E. Fazakas, L. Varga „The Influence of microstructure on compressive stress characteristics of the FINEMET-type nanocrystalline sensors” Journal of Optoelectronics and Advanced Materials 5 (2003) 705-708
5. R. Szewczyk, A. Bieńkowski, R. Kolano „Influence of nanocrystalisation on magnetoelastic Villari effect in Fe73.5Nb3Cu1Si13.5B9 alloy” Crystal Research and Technology 38 (2003) 320-324
6. A. Bieńkowski, R. Szewczyk „New possibilities of utilizing magnetoelastic Villari effect in Mn-Zn ferrites as stress sensors” Journal of Electrical Engineering 53 (2002) 107-109
7. R. Szewczyk, A. Bieńkowski, Z. Kaczkowski P. Svec „Magnetoelastic properties of Fe73.5Nb3Cu1Si13.5B9 alloy in amorphous and nanocrystalline state” Journal of Electrical Engineering 53 (2002) 110-113
8. A. Bieńkowski, K. Rożniatowski, R. Szewczyk „Effects of stress and its dependence on microstructure in Mn-Zn ferrite for power applications” Journal of Magnetism and Magnetic Materials 254-255 (2003) 547-549
9. A. Bieńkowski, R. Szewczyk „New possibility of utilizing amorphous ring cores as stress sensor” Physica Status Solidi A 189 (2002) 787-790
10. A. Bieńkowski, R. Szewczyk „The dependence of magnetoelastic properties of Zn-Mn ferrites on their magnetocrystalline properties” Physica Status Solidi A 189 (2002) 825-828
11. R. Szewczyk, A. Bieńkowski „Magnetoelastic Villari effect in high permeability Mn-Zn ferrites and modeling of this effect.” Journal of Magnetism and Magnetic Materials 254-255 (2003) 284-286
12. A. Bieńkowski, R. Szewczyk „New method of characterization of magnetoelastic properties of amorphous ring cores” Journal of Magnetism and Magnetic Materials 254-255 (2003) 67-69
13. Z. Kaczkowski, A. Bieńkowski, R. Szewczyk „Compressive stress dependence of magnetic properties of Co66Fe4Ni1B14Si15 alloy” Czechoslovak Journal of Physics 52 (2002) 183-186
14. A. Bieńkowski, Z. Kaczkowski, R. Szewczyk „Magnetostrictive properties of Ni-ferrite” Czechoslovak Journal of Physics 52A (2002) A85-A88
15. A. Bieńkowski, R. Szewczyk, R. Kolano „Magnetoelastic Villari effect in nanocrystalline Fe73.5Nb3Cu1Si13.5B9 alloy” Physica Status Solidi A 189 (2002) 821-824
16. R. Szewczyk, A. Bieńkowski, A. Kolano-Burian „Magnetosprężyste zjawisko Villariego w magnetykach amorficznych i nanokrystalicznych” Rudy i Metale Nieżelazne, R-47 (2002) 445-448
17. R. Szewczyk, A. Bieńkowski „Możliwości zmniejszenia niepewności wskazań magnetometru transduktorowego metodą programową” Zeszyty Naukowe Politechniki Śląskiej, Seria Elektryka 181 (2002) 175-184
18. A. Bieńkowski, R. Szewczyk „Magnetosprężyste sensory naprężeń i sił - Nowe możliwości” Pomiary Automatyka Robotyka 9 (2002) 14-17
Laboratory of Mechatronic Properties of Magnetic Materials Memebers: Prof. Adam Bieńkowski, PhD., DSc. Head of the Laboratory e-mail: [email protected].: +48-22-6608551 fax.: +48-22-8490395 Roman Szewczyk, PhD., Eng. e-mail: [email protected].: +48-22-6608519 mobil: +48-609-464741 fax.: +48-22-8490395 Jacek Salach, MSc., Eng. e-mail: [email protected] tel.: +48-22-6608519 fax.: +48-22-8490395
Laboratory for Growth and Physics of Low-Dimensional Crystals
(head: Prof. G. Karczewski)
and
Laboratory for Cryogenic and Spintronic Research
(head: Prof. T. Dietl)
in the Institute of Physics of the Polish Academy of Sciences in Warsaw
Al. Lotników 32/46, 02-668 Warsaw
Contact: Prof. Jacek Kossut, Director of the Institute of Physics of the Polish Academy of Sciences (phone 4822 843 68 71, fax 4822 8430927, email [email protected])
Main scientific interests of the two groups: experimental and theoretical investigations of electronic states in low dimensional quantum semiconductor nanostructures such as quantum wells, quantum wires and self-assembled quantum dots. The emphasis is on such structures made of II-VI-based diluted magnetic semiconductors such as CdMnTe. In particular studies of self assembled quantum dots with controllable number of magnetic ions are possible. Included are studies of ZnO-based material, in particular methods of achieving p-type conductivity are studied. Also fabricated and studied are hybrid structures combining diluted magnetic semiconductor quantum wells and micromagnets made of e.g. Co or Fe. The latter are studied to elucidate a possibility of use of fringe magnetic fields in localization of quasiparticles in quasi zero dimensional nanoareas of a sample. Major equipment and facilities: molecular beam epitaxy system, two magnetron sputtering systems, photolithography, atomic force and magnetic force microscopes, optical lab (including microluminescence set-up enabling studies of single quantum dots, magnetotransport and magnetooptic experimental set-ups). The second laboratory focuses its interest on properties of ferromagnetic semiconductors, development of new ferromagnetic semiconductors, studies of spin-dependent phenomena at low temperatures and fabrication of nanostructures by electron beam lithography. The major pieces of equipment include two dilution refrigerators operating down to 20 mK and in magnetic fields up to 9 T, electronolithographic system with interferometric laser stage, fully automated SQUID magnetometer with extreme sensitivity, x-ray microprobe, scanning electron microscope, two systems dedicated to DC and AC transport measurements in magnetic fields up to 11 T. The two laboratories constituted a part of the Center of Excellence CELDIS established in the Institute of Physics within the FP5. Leading scientists: doc. dr. Tomasz Wojtowicz, prof. Jacek Kossut, doc. dr Piotr Bogusławski, prof. T. Skośkiwicz, dr Jerzy Wróbel, dr Maciej Sawicki, dr Grzegorz Grabecki.
AFM (left) and MFM (right) images of elliptic iron microislands deposited by sputtering on a semiconductor quasi two dimensional quantum structure with the quantum well made of diluted magnetic semiconductor buried shallowly (30 nm) beneath the surface of the structure for studies of the influence of the fringe magnetic fields on optical properties of excitons trapped within the quantum well.
LOW DIMENSIONAL MAGNETIC STRUCTURES
Lech T. Baczewski, Anna Ślawska-Waniewska, Henryk K. Lachowicz
Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa, Poland,
Phone: + 48-22-843-5212; Fax: + 48-22-843-0926, [email protected]; [email protected]; [email protected]
http://www.ifpan.edu.pl/ Research on low dimensional magnetic systems, thin films and multi-layered as well as nanogranular structures is carried out in two laboratories in the Division of Physics of Magnetism of the Institute. In the Laboratory of Magnetic Hetero-structures the research is related to structural and magnetic properties of metallic thin films, in which the thickness of magnetically active layer is in the range of nanometers or even less. The following topics are presently under investigation:
Epitaxial growth modes of metallic thin films and structural characterization,Magnetic coupling and anisotropy in magnetic low dimensional structures (e.g. Cr/Gd, Co/Gd),
• Magnetic properties of rare earths (Gd, Tb) ultra-thin film, Spin reorientation transition, anisotropy in ultra-thin Co layers: influence of a cover layer in epitaxial Au/Co/X thin film wedge structures with perpendicular anisotropy, where X = Au, Ag, Cr, Al, Re, Induced magnetic moment in transition metals (V, Mn, Cr) in epitaxial TM/Gd bilayers, Growth and study of magnetic properties in metal-semiconductor hybrid structures (e.g. Fe/Si, Fe/Ge) and iron nitrides FeN.
The Laboratory possesses necessary expertise and technological facilities such as molecular beam epitaxy (MBE) and sputtering film deposition with controlled morphology. MBE Riber system is specially devoted for metallic thin films deposition being equipped with three high temperature (up to 1400°C) effusion cells and two electron guns allowing to deposit even the metals with very high melting point like W, Mo or Nb. Growth mode and film structure is characterized by RHEED and Auger spectroscopy, both in-situ, and AFM/MFM/STM Nanoscope III, TEM, X-ray reflectivity/diffraction ex-situ (Philips eXpert diffractometer). Magnetic properties are studied by means of VSM, SQUID, torque magnetometer, FMR, magneto-resistance method and magnetooptical measurements based on Kerr effect. High-resolution electron patterning and photolithography is also available in the Institute. Besides of investigation of the physical properties of thin films and their structures described above, nano-granular systems are also the research objects. This research, carried out in the Laboratory of Low Dimensional Magnetics, is focused on the investigation of complex structural and magnetic properties of the following nano-granular structures:
hybride materials consisting of isolated single domain iron oxides particles hosted in silica aerogels prepared by sol-gel methods,
assemblies of the ferrite particles prepared in three forms: – free standing as-produced particles, – particles covered by a surfactant, – particles embedded in a fluid (ferrofluids),
bcc-Fe-crystallites embedded in a metallic (magnetic and nonmagnetic) matrix. The studies will be focused on the surface/interface phenomena connected with the high sur-face-to-volume ratio in nano-structures mentioned above as well as broken symmetry at the boun-dary of the crystallites, in particular:
the spin structures and spin frustration at the boundary regions, the effect of surfaces on the relaxation processes, dynamic properties and the magnetic behaviour of the particles/thin films, the alteration of the inter-particle interactions by modification of the surface properties of the nano-material studied.
The aim of these studies is to improve the physical understanding of the magnetic behaviour of the multiphase granular materials mixed in the nano-scale, both from the point of view of basic physical knowledge as well as in respect of possible applications of these materials in electronics, optics and medicine.
It is also planned to carry out complex studies of electrical, magnetic and magneto-transport in nanogranular Fe-based systems obtained by annealing of amorphous alloys of the Finemet type (nominal composition FeCuNbSiB) produced by rapid quenching. The influence of the content of crystallites, their size and also their distribution on the resistance and magnetoresistance as well as magnetic properties will be investigated. These investigations will be performed in dependence of temperature, magnetic field and, in particular high hydrostatic pressure. It is expected that the obtained results will allow to determine the mechanisms responsible for all the studied phenomena in the Fe-based alloys consisting of magnetic nanoparticles embedded in the matrix exhibiting also magnetic properties. Similarly as in the former case, the Laboratory of the Low Dimensional Magnetics is equipped with the following facilities:
– vibrating sample magnetometer (VSM) with furnace and cryostat, – ac susceptometer with cryostat, – low temperature magnetoresistance measurement setup, – high temperature magnetoresistance measurement setup, – hysteresis meter (high temperatures), – magnetooptical Kerr-effect for the domain structure observation, – magnetoimpedance measurement system, – furnace for magnetic field annealing.
Laboratory of Magnetism
University of Białystok 41 Lipowa street
15-424 Białystok POLAND
Tel: (+48-85) 745 7229 Fax: (+48-85) 745 7223 http://physics.uwb.edu.pl/zfmag E-mail: [email protected]
1. Research team Head: Prof. Andrzej Maziewski Full-time employees: Dr. R.Gieniusz, Dr. M.Kisielewski, Dr.A.Stupakiewicz, Dr M.Tekielak Ph. D. students: Mr. W.Dobrogowski, Mr J.Jaworowicz, Mr Z.Kurant Part-time employees from NANOMAG-LAB project http://labfiz.uwb.edu.pl/zfmag/tok/. Magnetic nanostructures are studied in close cooperation with Polish teams from Warszawa, Kraków and Poznań and European teams from NANOMAG-LAB project.
2. Research fields :
2.1. Subjects: (i) magnetic anisotropy in thin and ultrathin films; (ii) domain structures and magnetization processes - experimental study using magnetoopical techniques, MFM and theoretical description, simulations; (iii) investigation of the relationship between structure and magnetic, magnetooptical properties of ultrathin layers; (iv) photomagnetic effects; (v) FMR in thin and ultrathin films; (vi) development of digital image processing procedures.
2.2. Materials under investigations : (i) magnetic nanostructures; (ii) garnets.
3. Research equipment : (i) computerized magnetooptical magnetometers (used different lasers light); (ii) micro-magnetometer (based on Carl Zeiss microscope equipped with high sensitivity CCD camera); (iii) FMR spectrometer working in X band; (iv) Cryostats for magnetooptical and FMR study (displex system enabling measurements from 10K) ; (v) STM, AFM (MFM option was performed).
5. Selected papers (full list: http://labfiz.uwb.edu.pl/zfmag/publikacje.php):
1. J.Sweklo, W.Dobrogowski, M.Kisielewski, A.Maziewski, The improvement of atomic force microscope suitable for magnetic domain structure measurements, Acta Physica Polonica A, 97 (2000).
2. A.Stupakiewicz, A.Maziewski, I.Davidenko, V.Zablotskii, Light-induced magnetic anisotropy in Co-doped garnet films, Phys.Rev.B 64, 644405 (2001).
3. A.Wawro, L.T.Baczewski, M.Kisielewski, I.Sveklo, and A.Maziewski, The MBE growth modes of Au/Co/Au sandwiches, Thin Solid Films, 412, 34 (2002).
4. N.Spiridis, M. Kisielewski, A. Maziewski, T. Ślęzak, P. Cyganik, J. Korecki, Correlation of morphology and magnetic properties in ultrathin epitaxial Co films on Au(111), Surface Science, 507, 546 (2002).
5. W.Cheikh-Rouhou, B.Bartenlian, P.Beauvillain, J.Ferré, V.Mathet, A.Stupakiewicz, SHG anisotropy in Au/C/Au/vicinal Si(111), JMMM, 240, 532, (2002).
6. M.Kisielewski, A.Maziewski, M.Tekielak, J.Ferré, S.Lemerle, V.Mathet, C.Chappert, MAGNETIC ANISOTROPY AND MAGNETIZATION REVERSAL PROCESSES IN Pt/Co/Pt FILMS, JMMM, 260 (2003) 231-243
7. M.KISIELEWSKI, A.MAZIEWSKI, J.FERRE, Numerical Simulations of Magnetization Reversal Processes in an Ultrathin Cobalt Film, physica status solidi (a), vol.196, No.1, 133-136 (2003).
8. M.Kisielewski, A.Maziewski, M.Tekielak, A.Wawro, L.T.Baczewski, New possibilities for tuning ultrathin cobalt film magnetic properties by a noble metals overlayer, Physical Review Letters 89, 8, 87203 (2002).
9. M.Kisielewski, Z.Kurant, M.Tekielak, W.Dobrogowski, A.Maziewski, A.Wawro, L.T.Baczewski, Magnetooptical micromagnetometry of ultrathin Co wedges, physica status solidi (a), vol.196, No.1, 129-132 (2003).
10. M.Kisielewski, A.Maziewski, V.Zablotskii, T.Polyakova, J.M.Garcia, A.Wawro, L.T.Baczewski, Drastic changes of the domain size in an ultrathin magnetic film, J.Appl.Phys., 93, No.10, 7628 (2003) .
11. R. Gieniusz, A. Stupakiewicz, O. Liedke, A. Maziewski, P. Gogol, P. Beauvillain, FMR study of ultrathin Co magnetic films on vicinal Si (111) substrates, JMMM, 272-276 (2004) e911.
12. M. Kisielewski, A. Maziewski, T. Polyakova, and V. Zablotskii, Wide-scale evolution of magnetization distribution in ultrathin films, Phys.Rev.B 69 (2004) 184419.
6. Now realised research projects: 6.1. Polish projects
Grant from Polish Committee for Scientific Research (KBN): (i) Modification of magnetic ordering on vicinal surfaces – spin engineering (ii) Magnetic ordering in ultrathin cobalt films – influence of coverage layer.
6.2. International project
Coordination of the project Combined study of nanostructured magnetic materials (Sixth Framework Programme of the EU Marie Curie Action TRANSFER OF KNOWLEDGE) http://labfiz.uwb.edu.pl/zfmag/tok/
INSTITUTE OF NON - FERROUS METALS
Laboratory of Rapidly Quenched Alloys
ul. Sowińskiego 5, 44-101 Gliwice, POLAND
tel. (+4832) 238 02 00, fax. (+4832) 231 69 33, e-mail: [email protected]
web site: www.imn.gliwice.pl
The Institute of Non-Ferrous Metals in Gliwice (IMN), established in 1952, is the main research
and development centre of the Polish non-ferrous metals industry. It conducts research and
performs implementation works covering a wide range of topics, including development of new
alloys and composites, processing of metals and alloys, environment protection, ores processing,
chemical analysis, and others. There are about 470 people working at the Institute, 250 of them in
the research section.
Part of the Institute’s Department of Materials Science and Powder Metallurgy is Laboratory of
Rapidly Quenched Alloys (with dr Roman Kolano as a Head of Laboratory of Rapidly Quenched
Alloys). Its research staff conducts research on the development of new Fe-based and Co-based
amorphous and nanocrystalline soft magnetic materials, soft magnetic Fe-Ni alloys, development of
technology for the production of master alloys, casting amorphous ribbons and heat and thermo-
magnetic treatment of toroidal cores wound from these ribbons, and development of technology for
the production of amorphous distribution transformers up to 400 kVA in rating. The research is
aimed to tailor magnetic properties of the nanocrystalline cores so as to make them suitable for
application in various electronic equipment (power supplies, sensors, etc.). The Laboratory has been
recently certified by the Polish Centre of Accreditation and meets requirements of the PN-EN
ISO/IEC 17025:2001 standards.
For many years the group of Laboratory actively collaborates with many scientific centres at
home and abroad especially from France, Hungary, Spain, Germany, Great Britain, Italy and
Slovakia. Laboratory has a close cooperation with industrial companies especially from electrical,
electronic and power electronic trade.
The Laboratory of Rapidly Quenched Alloys is equipped with classic technology appliances,
measuring apparatus, and testing installation for rapid quenching of alloys.
Technological part comprises:
• vacuum furnaces of 2 kg and 25 kg per cycle for master alloys production,
• casting machines for preparing amorphous ribbons (with capacity up to 2 kg/cycle, with Ar
protection with capacity up to 100 g - for casting of high requirements, difficult for
quenching or special, sophisticated alloys, and prototype upwards machines with capacity
up to 20 kg/cycle),
• device of bulk amorphous materials produced by copper mould casting in sub-pressure
conditions,
• winding machines,
• 3 furnaces for heat and thermo – magnetic treatment: laboratory furnaces is using to anneal
cores without magnetic field for examination of the influence of the annealing temperature
and time on magnetic properties, one of the industrial furnaces is using to anneal more
cores at the same time with or without presence of longitudinal magnetic field and second
of the industrial furnaces has a possibilities to use a transverse magnetic field during
annealing process,
Research part comprises:
• Accu Pyc 1330 for true density determination of materials,
• 2 X-ray diffractometers (URD 6 and XRD 7) for phase analysis and for analysis of textures,
• X-ray microanalyser, by JOEL company, with wave and energy dispersive spectrometers
and an attachment for diffraction of back-scattered electrons, by Oxford Instruments,
• equipment for measuring a dynamic soft magnetic properties: Ferrometr (very useful in
devices construction point of view) within a frequency range from 10 Hz up to 1 kHz,
2 Remacomp system (Magnet - Physik Dr. Steingroever GmbH) within frequency range
from 10 Hz up to 300 kHz
AGH_University of Science & Technology Faculty of Non-Ferrous Metals
Nano-technologies, Nano-science, Multifunctional materials
New production processes M.Richert1, L.Błaż, H.Dybiec, K.Fitzner
Abstract
The original technology of Cyclic Extrusion Compression (CEC) deformation is developed at Faculty of Non-Ferrous Metals at AGH. The CEC technology allows deformed metals and alloys to the arbitrary large deformations without the change of the sample shape. It is used for the production of bulk metallic nanomaterials, consolidation of powders, production of composites and other unconventional materials. Fig.1 presents the scheme of the laboratory version of CEC device and the sample inside the die. Fig.2 shows the new press for CEC industry production of nanomaterials and other unconventional material.
Fig.1. Scheme of Cyclic Extrusion Compression (CEC) device and sample inside the die Fig.2. The new press for CEC technology
The next theme is aluminum-based composites produced in collaboration with the Nihon University by mechanical alloying (MA). They consist of light metal powders with 8-10 wt. % additions of heavy-metal oxides (MeO). Received MA powders were consolidated by compression under the pressure of 100 MPa then hot extruded at 673 K. Two groups of composites were distinguished: (1) composites containing Me-elements that are insoluble in Al-matrix and (2) composites containing Me-elements that create Al-based intermetallics (Fig.3). 1 M.Richert, AGH, al. Mickiewicza 30, 30-059 Kraków [email protected]
Fig.3. Structure of Al-V2O5 composite annealed for 100 h at 873 K The consolidation of powders is the next technology developed at our faculty. The powders
after the consolidation consist from the ultra-crystalline and nanocrystalline particles. The technology used high temperature extrusion and KOBO technology (Fig.4).
Fig.4. The device for powder consolidation and obtained products
The thin layers technology ZnSe at copper is developed at chemistry group. The next possibility is production of different sizes of powders, which depend on the reactions rate (Fig.5). Fig.5. Nanopowders of Au
KIERUNKI ROZWOJU NANOMATERIAŁÓW I NANOTECHNOGII W POLITECHNICE SZCZECIŃSKIEJ
Magdalena Kwiatkowska, Zbigniew Rosłaniec
Politechnika Szczecińska, Instytut Inżynierii Materiałowej, Al. Piastów 19, 70-310 Szczecin
Prace badawcze w zakresie nanomateriałów i nanotechnologii w Politechnice Szczecińskiej realizowane są już od kilku lat przez cztery jednostki: Instytut Inżynierii Materiałowej, Instytut Technologii Chemicznej Nieorganicznej i Inżynierii Środowiska, Instytut Polimerów i Instytut Fizyki. Kierunki prowadzonych badań dotyczą zarówno syntezy materiałów o wymiarach nanoskopowych: nanocząstek metali i ich związków, jak i otrzymywania nanokompozytów polimerowych z wykorzystaniem zarówno termo- jak i duroplastów. Posiadany przez uczelnię sprzęt badawczy pozwala na kompleksową analizę uzyskanych nanomateriałów pod kątem ich składu, struktury czy właściwości fizycznych. Wiele prac na tym polu prowadzonych jest w ramach krajowych i międzynarodowych projektów badawczych oraz przy współpracy z zagranicznymi ośrodkami naukowymi.
Nanostructured functional materials
Prof. Mieczyslaw Jurczyk, Ph.D., D.Sc.
Institute of Materials Science and Engineering, Poznan University of Technology, 60-965 Poznan, Poland
Fax: +4861 665 3576, E-mail: [email protected], http://www.mse.put.poznan.pl/Wersja_ang
IINNTTRROODDUUCCTTIIOONN
During last years, interest in the study of nanostructured materials has been increasing at an accelerating time, stimulated by recent advances in materials synthesis and characterization techniques and the realization that these materials exhibit many interesting and unexpected physical, chemical as well as mechanical properties with a number of potential technological applications. For example, magnetic and hydrogen storage nanomaterials are the key to the future of the storage and batteries/cells industries. On the other hand, the recent development of nanostructured alloys, the demand for higher microhardness and the emergence of completely new technologies call for entirely new type of engineering nanomaterials with much higher mechanical properties.
Since 1996 a research program was initiated at Institute of Materials Science and Engineering, Poznań University of Technology in which nanostructured functional materials were produced [1-4].
The main objective of the presentation is to review the advantages of some nanomaterials, their application in various fields and the challenges involved in their fabrication. Details of the processing used and the enhancement of properties due to the nanoscale structures in consolidated materials will be presented. The measurements of the properties will also be included.
SELECTED NANOSTRUCTURED MATERIALS Nanocomposite permanent magnets
Remanence enhanced nanocomposite rare-earth-transition metal (RE-3d/α-Fe) materials, consisting of a hard magnetic RE-3d phase and an α-Fe soft magnetic phase, are of considerable current interest because of their possible use as a permanent magnets [1]. Technologically useful values of Hc are maintained for volume fractions of the soft phase in Nd2Fe14B/α-Fe up to 40%. In our work, the effect of M (M = Al-Cr, Cr, Zr or Mo) substitutions for iron on the magnetic properties in nanostructured two-phase Nd2(Fe,Co,M)14B/α-Fe materials, with an excess of α-Fe, has been investigated. With a small amount of Al-Cr, Cr, and other metals as Zr or Mo added to the cobalt substituted Nd12.6Fe69.8Co11.6B6/α-Fe, 4πMr and Hc are significantly improved.
For example, hot pressing at 1070 K of Nd12.6Fe69.3Co11.6Zr0.5B6/α-Fe powders, containing 37.5 volume fraction of magnetically soft α-Fe, produced an isotropic magnets with Jr = 0.99 T, JHc = 430 kA m-1, ρ ∼ 7.59 g cm-3. Temperature coefficients (from 293 to 413 K) of remanence α (Jr) and coercivity β (JHc) of these magnets are: -0.07 % K-1, -0.35 % K-1. The values of α and β are smaller than that of the sintered Nd-Fe-B magnets.
Nanocrystalline hydrogen storage electrode alloys
In view of the promising features of the Ni-MHx batteries, a large number of the hydrogen storage systems has been characterised, so far. Conventionally, the polycrystalline hydride materials have been prepared by arc or induction melting and annealing. However, either a low storage capacity by weight or poor absorption-desorption kinetics in addition to a complicated activation procedure have limited the practical use of metal hydrides. Substantial improvements in the hydriding-dehydriding properties of metal hydrides could be possibly achieved by the formation of nanocrystalline structures by non-equilibrium processing techniques such as MA or HEBM. Recently, mechanical alloying has been used to make a nanocrystalline TiFe-, ZrV2- LaNi5- and Mg2Ni-type (M) alloys [2]. Nanocrystalline and polycrystalline M-type compounds were prepared by mechanical alloying followed by annealing and arc melting method, respectively. The composite
M/10 % wag. Ni and M/10 % wag. Mg materials were also produced. Their physical, electrochemical as well as electronic properties were studied.
The electrochemical properties of studied materials are not only the function the microstructure but also the chemical composition of the electrodes. The obtained electrode properties are as follows:
- the reduction of the powder size and the creation of new surfaces is effective for the improvement of the hydrogen absorption rate - nanocrystalline alloys have shown almost complete elimination of the need for initial activation,
- composite M/10 wt. % Ni and M/10 wt. % Mg electrodes have shown an enhancement of the discharge capacities.
Additionally, the chemical composition and the cleanness of the surface of polycrystalline and nanocrystalline alloys were studied by XPS and AES methods. The oxygen content in materials produced by MA process was less than 2 at.%.
XPS studies showed that the shape of the valence band measured for the arc melted, polycrystalline-type compounds is practically the same compared to that reported earlier for the single crystalline samples. Any substitution leads to significant modifications of the electronic structures of the polycrystalline samples. On the other hand, the XPS valence bands of the MA nanocrystalline alloys are considerably broader compared to that measured for the polycrystalline samples. The strong modifications of the electronic structures of the studied nanocrystalline alloys could significantly influence on its hydrogenation properties.
Ferroelectric nanostructures
The ever increasing requirements on miniaturization and efficiency of electronic components result in efforts to incorporate new materials into silicon-based microelectronics, in order to overcome the physical limits of classic materials. In the nanometer range, the properties of most materials strongly depend on their outer dimensions, and the functionality of the material can even be lost below a certain size. Among functional materials ferroelectrics are expected to play an important role because they find various applications in a remarkably broad spectrum of advanced electronic, electromechanical and electrooptic components. The application of ferroelectrics in non-volatile ferroelectric random access memories (NV-FRAMs) of high memory capacity pushes the lateral size of the individual element down to several tens of nanometers or even several nanometers. The interface-to-volume ratio becomes very large, so that the properties of the memory elements may become interface-determined. The nature of the ferroelectric size effects has been discussed for decades; however, a unified picture is still missing. Recently we demonstrated that misfit dislocations play an important role on physical properties of nanoislands and material losses its ferroelectric properties [3].
Our scientific interest is focused on nanofabrication of different ferroelectric nanostructures (like nanoislands, nanopowder, nanotubes etc.). The obtained nanomaterials are characterised in our labolatory by XRD, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM).
Nanoporous silicon In the past few years, electrochemical etching of silicon wafers has been extensively investigated in the Institute. Electrochemical etching of silicon electrodes at different voltage conditions, results in well pronounced porous structure in bulk silicon, as well as oxide layer formed on the surface. Both structures find different applications. Due to excellent opto-electronic properties and high surface area, porous silicon is commonly use in waveguides, photonic crystals, sensors. Nanoporous silicon shows luminescence and electroluminescence. Oxides on silicon surface can be use in isolator and lightguide devices. Preparation of porous Si involve electrochemical dissolution of Si wafers in HF or/and NH4F containing solutions [4]. To better control of the silicon structure, necessary was the investigation of the potential range of the pore and oxide formation. It is accepted that to dissolution of the Si, necessary is the presence of free holes at the semiconductor surface and hence in n-Si necessary is
the presence of an illumination from external light source. Roughening of the surface of the n-Si is observed on photocurrent-voltage curve up to the first photocurrent peak and at potentials slightly anodic from the open circuit potential porous Si start to growth. We find extremely local formation of nanopits in silicon surface due to electrolyte countercharge immobilisation at specific surface sites of the ideally hydrogen terminated (111) surface. By careful selection of the experimental parameters we were able to show that charge localisation in electrochemical systems initiates the formation of nanometer dimensioned pits. On the base photoelectron spectroscopy, we explain dissolution model. At higher anodic potentials, silicon oxide formation and electropolishing occurs. The oxide formation and its dissolution results in current oscillations observed at higher anodic potentials (>3V versus SCE).
ACKNOWLEDGEMENTS
Support for this work was provided by the Polish National Committee for Scientific Research.
References: 1. J. Jakubowicz, M. Jurczyk, A. Handstein, D. Hinz, O. Gutfleisch, K.-H. Müller, Temperature
dependence of magnetic properties for nanocomposite Nd2(Fe,Co,M)14B/α-Fe, J. Magn. Magn. Mater. 208 (2000) 163-168.
2. M. Jurczyk, The progress of nanocrystalline hydride electrode materials, Bull. Pol. Ac.: Tech. 52(1) (2004) 67-77.
3. M.-W. Chu, I. Szafraniak, C. Harnagea R. Scholz, D. Hesse, M. Alexe, U. Gösele, Impact of misfit dislocations on polarization instability of epitaxial nanostructured ferroelectric perovskites, Nature Materials, 3 (2004) 87-90.
4. J. Jakubowicz, H. Jungblut, H.J. Lewerenz, Initial surface topography changes during divalent dissolution of silicon electrodes, Elecvhim. Acta 49 (2003) 137-146.
Contact persons: Nanocomposite permanent magnets and nanoporous silicon: Dr. Eng. Jaroslaw Jakubowicz phone: +48 61 665 3781, E-mail: [email protected] Ferroelectric nanostructures Dr. Izabela Szafraniak, phone: +48 61 665 3779, E-mail: [email protected]
INSTITUTE OF METALLURGY AND MATERIALS SCIENCE
POLISH ACADEMY OF SCIENCES
REYMONTA 25, 30-059 KRAKÓW, POLAND
Tel: (0-12) 637 42 00 Fax: (0-12) 637 21 92
http://www.imim.pl/
Amorphous and nano materials in IMIM PAN
Actually the research concerning the amorphous and nanocrystalline materials is carried out
in that direction of a powder metallurgy technologies of production of bulk amorphous alloys and
nanomaterials. They are carried out in two directions:
1) Development of powder metallurgy technologies of production of bulk alloys mainly in at
Zr-matrix alloys, like ZrNiCuTi,ZrCuAl, ZrCuNiTiAg and others, within a framework
project UE – “Plasticity of bulk amorphous glasses and application”
2) Mechanical alloying and hot pressing of titanium base powders in order to obtain
nanomaterials with low porosity, good ductility and high strength. This subject matter is
elaborated within polish government project “Technologies of production of metallic
nanomaterials“.
In order to realize above subjects the several experimental techniques are used:
• Processing techniques as:
mechanical alloying in the high energetic planetary mills Fritsch P5/4,
uniaxial-hot pressing and hot extrusion of milled powders
Equal Channel Angular Pressing (ECAP)
rapid solidification
• Thermal analyses by TA Instruments DSC Q1000, SDT Q600 allows to determine
the characteristic temperature of phase transitions as well as glass transition
temperature
Fig. 1 presents an example of DSC measurement using DSC Q1000 instrument the of milled Zr-Cu-
Al amorphous powder allowed to identified the temperature range of glass transition region.
Fig. 1. DSC analysis of Ti-Zr-Ni-Cu milled powder
• The structure of alloys is studied using scanning and transmission electron
microscopy by SEM Philips XL 30, ESEM FEI XL30, TEM Philips CM20 and
including HRTEM by TECNAI G2 F20
Fig. 2 shows an example of structure investigation of powder particle of Ni45Al45Fe10 ball milled
alloy.
R1/R2=1.41=d(001)/d(011)R1/R2=1.41=d(001)/d(011)
Fig. 2 Bright Field and HRTEM micrographs of Ni45Al45Fe10 ball milled alloy. Fourier transform
from HRTEM image shows rings corresponding to d001 and d011 lattice spacings.
Mechanical properties of hot pressed and severe plastic deformed samples by ECAP
are investigated using tensile, compression and hardness testes.
Contact persons: Prof. Jan Dutkiewicz, [email protected] (Head of projects, structure characterization, mechanical properties)
Prof. J. Kuśnierz, [email protected] (ECAP technique)
Dr. Wojciech Maziarz, [email protected] (mechanical alloying and hot consolidations, structure characterisation)
Dr. Tomasz Czeppe, [email protected] (thermal analyses, structure characterization)
Faculty of Materials Science and Engineering Warsaw University of Technology
ul. Wołoska 141, 02-507 Warsaw, Poland phones: +48 22 849 9929, 660 8729, fax: +48 22 660 8514
www.inmat.pw.edu.pl, [email protected]
The Faculty of Materials Science and Engineering, WUT, has a hundred years long record of
the investigations in the field of Materials. Its general research and education activities are focused on the relationships between the manufacturing process, materials structure and their properties. The teaching and research programmes are divided into four Divisions: Fundamentals of Materials Science, Design of Materials, Structural and Functional Materials, Surface Engineering. The current investigation area comprises, amongst others, nanostructured materials. Nowadays, more than a half of the academic and research staff of the Faculty deal with various aspects related to nanomaterials, mainly metallic ones.
The main techniques of production of nanomaterials used at the Faculty are: crystallisation of metallic glasses, mechanical alloying, severe plastic deformation and powder synthesis from plasma. These common techniques are used to produce the materials with various chemical composition, with various properties and hence various applications. The nanomaterials investigated at the Faculty may be distinct from application viewpoint into two main groups: structural materials and functional materials.
The process of manufacturing of nanomaterials may be carried out through the amorphous state (e.g. partial crystallisation of Al-based metallic glasses, magnetically soft and hard alloys) or may involve only the crystalline phases (as in the case of severe plastic deformation, mechanical alloying or deposition from vapour or plasma). The Faculty of Materials Science and Engineering presents a unique combination of expertise and facilities and its research is organised around the main areas: processing and characterisation of structure and properties of nanocrystalline materials. Fabrication of nanomaterials in the Faculty is carried out using the following techniques:
• rapid solidification and crystallisation of metallic glasses, used for Fe- and (Fe, Co)-based soft magnetic materials (Finemet, Nanoperm, Hitperm-type
alloys), Fe- based hard magnetic materials (Nd-Fe-B and Sm-Fe-N), Al-based structural materials (Al-Si-Ni-Mm and Al-Ni-Mm-TM2, where Mm =
mischmetal and TM2 = transition metal) alloys, • mechanical alloying, used for Fe-, Ni-, Al- and Ti-based intermetallic materials, the intermetallic materials reinforced with second phase particles (nanocomposites), hard magnetic materials,
• severe plastic deformation, used for pure metals and model alloys (Fe, Al, Ni, Ti, Cu), alloys of practical importance (e.g. stainless steels), intermetallics (e.g. Ni3Al, Ti3Al and TiAlNb),
• CVD/PVD (chemical/physical vapour deposition), IPD (impulse plasma deposition), used for nanopowders of diamond and very hard coatings and layers.
One of the very strong assets of the Faculty is its laboratory equipment for structure and properties characterisation. The Faculty’s advantage is a set of pieces of modern equipment used for characterisation of materials, from macro scale (e.g. computer driven testing machines), across optical microscopes with software for computer-aided image analysis, down to nano scale
(analytical transmission electron microscope). The laboratories are furnished with the following equipment (selected items):
• equipment for structure characterisation: transmission electron microscopes:
− JEOL 3010 (300 kV, resolution 1.9Å, microprobe chemical analysis – resolution 2 nm, sophisticated diffraction analysis)
− JEOL 1200EX (120 kV, scanning beam, in situ observations) − Philips 300EM (100 kV, in situ observations)
microprobe X-ray analyser CAMECA SEMPROBE SU-30 X-ray diffractometers:
− Bruker D8 DISCOVER Series 2 (high-resolution diffraction, high-resolution reflectometry, stress analysis, texture analysis, X-Y mapping of flat samples, microdiffraction, standard powder diffraction),
− Philips 1830, − Philips 1080,
Atomic Force Microscope Multi Mode Nanoscope III • equipment for properties evaluation: testing machines (MTS, Instron) hardness testers (microhardness and macrohardness) evaluation of magnetic properties
− magnetic balance − hysteresis loop tracers (room temperature and max. 700°C) − pulse hysteresis loop tracer − vibrating sample magnetometer to be purchased in 2005
evaluation of thermal properties (calorimeters): − Perkin Elmer DSC7 (max. temperature 730°C) − SETARAM Labsys DSC / DTA (max. temperature 1600°C)
evaluation of chemical properties • equipment for materials manufacturing and processing furnaces (air, vacuum, controlled atmosphere) up to 1600°C glow discharge thermochemical treatment furnaces melt spinners (with protective atmosphere or vacuum) impulse plasma accelerator ball mills mechanical and hydraulic presses.
The Faculty’s research in the field was recently supported by the grants from NATO and EU: • “Magnetic nanocomposites for transformer cores and magnetic refrigeration”, contract No. SfP-
971930, 1999-2003), • “Manufacture and characterisation of nanostructured Al alloys”, contract No. HPRN-CT2000-
00038, 2000 – 2003, • “Magnetic nanomaterials for high temperature and high frequency applications in power
electronics”, contract No. G5RD-CT-2001-03009, 2001-2004), as well as from domestic sources in the form of numerous grants from the State Committee for Scientific Research. In 2002, the EU acknowledged the high level of expertise and capabilities of the Faculty in the field of research of materials and supported two Centres established at the Faculty:
• Centre of Excellence: Nanocrystalline Materials: Fabrication, Structure, Modelling, Properties and Applications (“NanoCentre”), contract No: G5MA-CT-2002-04043, 2002 – 2005, www.nanocentre.inmat.pw.edu.pl
• Centre of Competence in Safety of Pressure Equipment “PRESAFE”, contract No. G1MA-CT-2002-04018, 2002 – 2005, www.inmat.pw.edu.pl/~presafe .
THE MAGNETIC MATERIALS LABORATORY IN TELE & RADIO RESEARCH INSTITUTE IN WARSAW
Assoc. Prof. Barbara Ślusarek D. Sc., Ph. D., Eng.
Tele & Radio Research Institute, Ratuszowa 11, 03-450 Warsaw, Poland (+48 22) 619 22 41 ext. 265 Fax (+48 22) 619 29 47 [email protected]
The technology of permanent magnets and designing magnetic circuits is the area of interests of Tele & Radio Research Institute in Warsaw since 70’s. Today’s researches are focused on the dielectromagnets (bonded magnets) from powder of Nd-Fe-B melt-spun ribbon and from mixture of powders. The works are concentrated on the designing of the physical properties of compression and injection molded dielectromagnets (magnetic, mechanical, thermal and electrical parameters) from one side and on the magnetisation of the prepared dielectromagnets to multiple pole orientation from the other. Laboratory works presently on the Nd-Fe-B dielectromagnets intended to work in both evaluated and low temperatures.
In the same time Magnetic Materials Laboratory in co-operation with the industry conducts the works on the application of dielectromagnets in electrical micromachines as stepping and dc motors, high speed brushless PM motors, and appliance of stators from soft magnetic iron powder in motors excited with Nd-Fe-B dielectromagnets.
Laboratory is equipped to prepare samples of dielectromagnets: mixers, presses, dryers, different magnetising equipment and physical properties measuring equipment as: hysteresisgraph for magnetic properties investigation in room and in sub and elevated temperatures measuring, strength resistance meters.
The dielectromagnets with isotropic characteristics can be later magnetized along whichever direction. It is also possible the multi-pole magnetizing of dielectromagnets with configuration of magnetic poles adjusted to the design and layout of the electric motor. Magnetic Materials Laboratory in Tele & Radio Research Institute is equipped with magnetizer as a power supply source for the magnetizing heads.
Faculty of Physics, Warsaw University of Technology Laboratory of Metallic Glasses
św. Andrzeja Boboli 8, 02-524 Warszawa, Poland
Team Leader dr Krystyna Pękała –[email protected] dr Piotr Jaśkiewicz [email protected] Jerzy Antonowicz [email protected]
Mechatronics Building, rooms 322, 323, tel. 660 82 14, fax (22) 660 8419
Avaliable equipment: Devices for thermopower and electrical resistance measurements with data acquisitions and control systems based on PC. Devices are working under vacuum and can gather data from the temperature range 300 - 1200K in both isothermal and constant heating rate (isochonal) modes. Electrical resistivity is measured in the DC, four probe system. Thermopower unit works in the two heaters system with the temperature gradient controlled independently and thermopower voltage measured between platinum parts of Pt-PtRh thermocouples.
By means of Temperature Coefficient of Resistivity (TCR) and Temperature Coefficient of Thermopower (TCT) we can get informations about Fermi energy value and the shift of kF (Fermi vector) in the relation of structural factor maximum position. This is specially usefull in the analysis of crystallizing amorphous alloy containing RE atoms, which exhibit unique d and f orbitals filling rules [1, 2, 3, 5].
The modified Maxwell – Garnett relation between sample and crystalline phases resistivities from the one side and volume fraction of crystalline phase from the second side is usefull in determining the relation of this crystalline fraction vs temperature. The kinetic parameters of transformations controlled by nucleations and growth or spinodal decomposition mechanisms can be determined from the isothermal or constant temperature growth rate resistivity run. Both techniques give the possibility to determine the conditions of the nanocrystallization process [4, 6, 7, 8, 9].
New theoretical model of electrical resistivity – temperature relation was developed for Al-Re nanocrystallizing alloys [7], on the basis of Maxwell-Garnett relation:
ρ - sample resistivity, x - transformed fraction ρa - amorphous phase resistivity ρc - crystalline phase resistivity
x a
c a
c a
a
=−
−
+
+
( )
( )
( )
( )
ρ ρ
ρ ρ
ρ ρ
ρ ρ
2
2, where
The analysis of electron transport properties of numerous alloys, made on the basis of
Ziman’s nearly free elctron theory and localization theory, can determine the relationship between the strength of bonds SM-TM (simple metal – transition metal) and the composition of crystallizing alloy.
Thermopower unit. Measurement of STEM proceeds under vacuum of 10-6 hPa. Temperature range : from ambient to 1200K. Thermopower range : ± 100.0 µV/K. Thermopower tolerance : ± 0.1 µV/K. Temperature/time run: isothermal, with temperature tolerance ± 0.5 deg; isochronal, with heating rate from the range 0.5 ÷20 deg/min. Sample dimensions : preferred shape – ribbon; length of 15 mm, thickness of 5 ÷ 1000 µm, width of 0.005 ÷ 3 mm. Temperature gradient : 2 ÷ 20 deg. Electrical resistance unit. Measurement of TCR proceeds under vacuum of 10-6 hPa. Temperature range : from ambient to 1200K. Resistivity range : 1 ÷ 500µΩcm and 1 ÷ 2000µΩcm. Resistivity tolerance : ± 0.5µΩcm. Temperature/time run: isothermal, with temperature tolerance ± 0.5 deg; isochronal, with heating rate from the range 0.5 ÷40 deg/min.
Sample dimensions : preferred shape – ribbon; length of 15 mm, thickness of 5 ÷ 1000 µm, width of 0.5 ÷ 3 mm.
Thermopower and Electrical Resistance Units :
Magnetic glass – temperature
dependence of resistivity. Tx - crystallization oneset TC - Curie temperature Θ - Debye temperature ρa - amorphous phase resistivity
200 400 600 800 1000 1200
1,00
1,02
1,04
1,06
1,08
1,10
1,12 FINEMET
TX
TC
Θ ρ/ρ
RT
T [ K ]
⎪⎪⎩
⎧
<+<<+
<+
TTTbaTTforTcTa
TTcaT
C
⎪⎪⎨ += b Caρ
33
2222
211
)( θθ
Sample CCCuuuCCuuCCuu
THERMOPOWER
Gradient heaters
Data acquisition and control system
Sample CCCeeerrraaaCeramics
RESISTIVITY
Data acquisition and control system
Metallic glass – temperature dependence of resistivity.
Amorphous – crystalline transformations, Al-Tb
Implementation of Maxwell-Garnett relation
300 400 500 600 700 800
152025303540455055
ρ [µ
Ωcm
]
K ]
I stage of transformation amorphous state
Next stages of transformation
Reactions in a crystalline state Recrystallization
T [
Literature. 1. K. Pękała, Journal of Non-Crystalline Solids, 287(2001)183-186 „Thermoelectric Power of Al-
Y-Ni Alloys” 2. K. Pękała, J.Latuch, T.Kulik, J. Antonowicz, P. Jaśkiewicz, Mater. Sci. Eng. A 375-377 (2004)
377 „Magnetic and Transport Properties of Nanocrystallizing Supercooled Amorphous FeAlGaPBSi Alloys”
3. K. Pękała, J.Latuch, M.Pękała, I. Skorvanek, P. Jaśkiewicz, Nanotechnology 14(2) (2003) 196 „Transport and magnetic properties of HITPERM alloys”
4. K. Pękała, P. Jaśkiewicz, J.L.Nowiński, M.Pękała, J.of Magnetism and Magnetic Materials 262 (1) (2003) 146-149 „Electrical Resistivity of Nanocrystals in Fe-Al-Ga_P-B-Si Alloy”
5. K.Pękała „Thermoelectric Power of Nanoperm Alloys”, Interface and Transport Dynamics – Cmputational Modelling ed H.Emmerich, B.Nestler, M. Schreckenberg, vol 32, Springer Verlag 2003, p75
6. K.Pękała, J.Latuch, P.Jaśkiewicz, J.L.Nowiński, J.Antonowicz, J. of Metastable and Nanocrystalline Materials vol 21-22 (2004), 494 „Electron Structure, Stability and Nanocrystallization of Al-based Amorphous Alloys“
7. L.Łukaszuk, K.Pękała, Nanotechnology 16 (2005) 169-174 „Nanocrystallization of Al92Sm8 studied by electrical resistivity-formation of monoatomic Sm spherical layer”
8. J.Antonowicz, Archives of Materials Science 25 (2004) 403 „Nanocrystallization of Al - rare earth amorphous alloys studied in-situ by real-time X – ray diffraction”
9. K.Pękała, M.Pękała, I.Skorvanek, J. of Non-Crystalline Solids 347 (1-3) (2004) 27 „Electrical resistivity of nanocrystalline Fe73.5Nb4.5Cr5Cu1B16 alloys”
Institute of Materials Science Silesian University
http://uranos.cto.us.edu.pl/~inom
40-007 Katowice, 12 Bankowa, Poland tel.(48-32) 259-69-26, fax (48-32) 259-69-29, e-mail: [email protected]
The scientific activities of the Institute of Materials Science (the former name Institute of
Physics and Chemistry of Metals) concern the knowledge of materials and material engineering. The research concentrates mainly on metals, their alloys, polymers and ceramics. The main aim of the carried out research is looking for and interpreting the interdependencies and connections between real structure, chemical composition of a material and their construction and functional properties. This research combines both cognitive and application aspects.
The main fields of the research activities cover: i) phase transformations, real structure and properties of metals, ceramics and polymers, ii) new materials including shape memory alloys, amorphous alloys, intermetallic phases, quasicrystals and composites, iii) some electrochemical processes, materials for electrodes, phenomena connected with the interaction of hydrogen with alloys, iv) development and improvement of methods for material studies.
Amorphous and nano-crystalline alloys are one of the most important group of materials on which the interest of the Institute is concentrated. Mainly we are interested in searching of new soft magnetic materials and from this point of view we study the optimization of soft magnetic properties in amorphous alloys. Our examinations concern structural relaxation, nanocrystallization and crystallization. Recently we have examined the influence of different alloying additions on soft magnetic properties of the following amorphous alloys from the so-called finemet family: Fe-X-Si-B (X=Cr, Zr, Mo, V, Cu, Al, Nb, Co), Fe-Cu1-X-Si-B (X=Cr, Zr, Mo, Mn, Co), and nanoperm family: Fe-X-B (X=Zr, Nb, Cr), Fe86-xNbxB14 (2<x<8). For studying the structural relaxation we use magnetic relaxation technique and measurements of Young modulus (mechanical spectroscopy). In order to obtain diffusion parameters (i.e. distribution of activation enthalpies) we elaborated a method of separation of the two components of structural relaxation – reversible and irreversible one. For finemet type alloys we have shown that the crystallization (nanocrystallization) temperature as well as the 1-hour optimization annealing temperature in the first approximation is proportional to the atomic radius of alloying addition. Moreover we have shown that in some cases the permeability enhancement effect (optimization) can take place in the so-called relaxed amorphous state which gives good soft magnetic material essentially free of embrittlement. We are also interested in applications of soft magnetic materials as magnetic and electromagnetic shields. In the nearest future we are planning to study amorphous alloys with relatively high magnetostriction i.e. to study the influence of alloying additions like Dy and/or Tb on magnetic properties of amorphous alloys based on iron. In the field of mechanical spectroscopy we collaborate with Max-Planck Institut für Metallforschung – Stuttgart, Germany (dr M. Weller). RESEARCH EQUIPMENT
1. Magnetic measurements
• magnetic balance (field about 1T, temperature range 100 - 1000 K; magnetization measurements are used to study magnetic properties and nanocrystallization of amorphous alloys),
• Maxwell Wien bridge (initial magnetic permeability measurements - feld 0.2-0.5 A/m, temperature range 200 - 500 K, frequency 0.5 -10 kHz; This measurements are used to study optimization of magnetic properties),
• magnetostriction (field up to 1T, temperature range 300 – 1000 K), • fluxmeter - magnetization curves (field up to 10 kA/m),
• coercivemeter (field up to 160 kA/m; examination of optimization of soft magnetic properties).
• Villari effect (field up to 10 kA/m, stress up to 108 Pa).
2. Electric measurements • resistivity measurements (four points probe, temperature range 100 - 1000 K; in situ
measurements of isothermal and isochronous curves; examination of crystallization in amorphous alloys),
• magnetoresistance (field 1T), • Hall effect (field 1 T; conductivity examination).
3. Mechanical spectroscopy
• Young modulus measurements (reed apparatus, free vibrations technique - E ∝ f2(T) and internal friction Q-1(T), temperature range 300 - 1000 K, frequency 20 - 150 Hz),
• inverted torsion pendulum (shear modulus measurements using free vibrations technique; G ∝ f2(T) and internal friction Q-1(T); temperature range 100 - 1000 K, frequency range 0.5 – 10 Hz).
4. Structural examinations
• X-ray diffractometer Philips X’Pert type PW 3040/60, X-ray diffractometer Philips type PW 1130 (basing on the computer programs the Radial Distribution Function for amorphous materials can be established; we also use the Rietveld method of spectra analysis),
• high resolution transmission electron microscopy JEM 3010 (selected area electron diffraction (SAED) as well as the convergent beam diffraction (CBED) techniques are used for phase identifiaction and determination of point and space groups),
• Mössbauer spectroscopy (two spectrometers of the Mössbauer effect (57Fe, 119Sn); temperature range 80 – 800 K; gas scintillation detector of conversion electrons for Mössbauer’s spectroscopy),
• spectrometer of positon annihilation (positon life time and Doppler’s widening).
5. Thermal analysis methods • Perkin-Elmer scanning microcalorimeter (DSC) (temperature range 300 – 850 K,
examinations of phase transformations e.g. crystallization of amorphous alloys), • Mettler differential thermo-analyser (DTA) temperature range 300 – 1500 K.
Last selected papers:
1. G.Haneczok, J.Rasek, Free volume diffusion and optimization of soft magnetic properties in amorphous alloys based on iron, Defect and Diffusion Forum, 224-225, 13-26 (2004).
2. A.Chrobak, D.Chrobak, G.Haneczok, P.Kwapuliński, Z.Kwolek, M.Karolus, Influence of Nb on the first stage of crystallization in the Fe86-xNbxB14 amorphous alloys, Materials Science and Engineering A, 382, 401-406 (2004).
3. P. Kwapuliński, J. Rasek, Z. Stokłosa, G. Haneczok, Magnetic properties of amorphous and nanocrystalline alloys based on iron, Journal of Materials Processing Technology, 157-158, 735-742 (2004).
4. J.E.Frąckowiak, G.Haneczok, P.Kwapuliński, J.Rasek, A.Chrobak, The Mössbauer study of permeability enhancement effect in the Fe86-xNbxB14 (x=5, 6) amorphous alloys, Czechoslovak Journal of Physics, 54, D109-D112 (2004).
5. G.Haneczok, M.Weller, A fractional model of viscoelastic relaxation, Materials Science and Engineering A 370, 209-212 (2004).
