Nano and Microstructural Design of Advanced Materials. A Commemorative Volume on Professor G. Thomas' Seventieth Birthday

294 Pages·2003·13.265 MB·English

by  M.A. Meyers, R.O. Ritchie and M. Sarikaya (Eds.)

Preface
The importance of the nanoscale effects has been recognized in materials research for over fifty
years. The understanding and control of the nanostructure has been, to a large extent, made
possible by new atomistic analysis and characterization methods. Transmission electron
microscopy revolutionized the investigation of materials. This volume focuses on the effective
use of advanced analysis and characterization methods for the design of materials. The nano-
structural and microstructural design for a set of targeted mechanical/functional properties has
become a recognized field in Materials Science and Engineering. This book contains a series
of authoritative and up-to-date articles by a group of experts and leaders in this field. It is based
on a three-day symposium held at the joint TMS-ASM meeting in Columbus, Ohio. The book
is comprised of three parts: Characterization, Functional Materials, and Structural Materials. The
book is dedicated to Gareth Thomas who has pioneered this approach to materials science and
engineering area over a wide range of materials problems and applications.
Professor Thomas' lifetime in research has been devoted to understanding the fundamentals
of structure-property relations in materials for which he has also pioneered the development
and applications of electron microscopy and microanalysis. He established the first laboratory for
high voltage electron microscopy, at the Lawrence Berkeley National Laboratory. His research
has contributed to the development and nano/microstructural tailoring of materials from steels
and aluminum alloys, to high temperature and functional ceramics and magnetic materials, for
specific property performances, and has resulted in a dozen patents.
Professor Thomas is a pioneer and world leader in the applications of electron microscopy
to materials in general. Following his Ph.D. at Cambridge in 1955, as an ICI Fellow, he
resolved the problem of intergranular embrittlement in the Al/Zn/Mg high strength alloys
which failed in the three Comet aircraft crashes and became identified with Prof. Jack Nutting
as the "PFZ" -precipitate-free-zones, condition, now in wide general use to describe grain-
boundary morphologies leading to intergranular corrosion and mechanical failure. This work
prompted Dr. Kent van Horne of Alcoa to invite him to spend the summer of 1959 in their
research labs at New Kensington, Pa. From there and after a trans-USA lecture tour he was
invited in 1960 to join the Berkeley faculty, (becoming a full professor in 1966), where he
started a major research program within the newly formed "Inorganic Materials Research
Division" of the (now) Lawrence Berkeley National Laboratory. It was there, after nine years'
effort, that he founded the National Center for Electron Microscopy, which opened in 1982 and
which he directed until he resigned in 1993, to spend 1.5 years helping establish the University
of Science & Technology in Hong Kong. There he also set up and directed the Technology
Transfer Centre. He returned to Berkeley in 1994 to continue teaching and research, and in his
career has over 100 graduates. With his students and colleagues he has over 500 publications,
several books, including the first text on Electron Microscopy of Metals (1962), and in 1979 - with
M.J. Goringe, a widely used referenced text- Transmission Electron Microscopy of Materials
which was also translated into Russian and Chinese.
His academic career in Berkeley has included administrative services as Associate Dean,
Graduate Division, Assistant and Acting Vice-Chancellor-Academic Affairs, in the turbulent
years of student unrest (1966-72). He was the Chair faculty of the College of Engineering
(1972/73), and Senior Faculty Scientist, LBNL-DOE, which sponsored most of his research
iv ecaferP
funding. In 1995 he received the Berkeley Citation for "Distinguished Achievement" at UC
Berkeley. Professor Thomas was Associate Director, Institute for Mechanics and Materials,
UC San Diego, from 1993 to 1996. In this capacity, he formulated new research directions and
stimulated research at the interface of Mechanics and Materials. He is currently Professor in the
Graduate School, UC Berkeley, Professor-on-Recall, UC San Diego, and VP R&D of a new
company, MMFX Technologies, founded in 1999, to utilize steels for improved corrosion
resistant concrete reinforcement. In the USA the infrastructure repair costs are in the trillion
dollar range. In 2002 the company received the Pankow award (American Inst. of Civil Engineers)
for innovation in Engineering, based on Prof. Thomas' patents on nano microcomposite steels.
Professor Thomas has also played an important role in promoting the profession. He was
president of the Electron Microscopy Society of the US in 1974, and in 1974 he became
Secretary General of the International Societies for Electron Microscopy for an unprecedented
21 years, and was president in 1986-90. He lectured extensively in foreign countries and
helped promote microscopy and materials in developing countries, also serving as advisor in
China, Taiwan, Korea, Singapore, Poland, Mexico, et al. He also served on many committees
of the ASM and TMS, and the National Research Council. After reorganizing the editorial
structure of Acta and Scripta Metallurgica (now Materialia), when in 1995 he took over as
Editor-in-chief, he became Technical Director, Acta Mat. Inc. 1998 until April 2002. He was
Chairman of the Board in 1982/84.
In recognition of his many achievements, Professor Thomas has received numerous honors
and awards, including, besides his Sc.D.-Cambridge University in 1969: Honorary Doctorates
from Lehigh (1996) and Krakow (1999); The Acta Materialia Gold Medal (2003), The ASM
Gold Medal (2001), Sauveur Achievement Award (ASM- 1991), Honorary Professor, Beijing
University of Sci. & Technology (1958), Honorary Memberships in Foreign Materials societies
(Japan, Korea, India, etc.), E.O. Lawrence Award (US Dept. of Energy-1978), Rosenhain
Medal (The Metals Soc-UK- 1977), Guggenheim Fellow (1972), von Humboldt Senior Scientist
awards (1996 & 1981), the I-R Award (R&D Magazine-1987), Sorby Award, (IMS-1987) and
the Distinguished Scientist Award (EMSA-1980). He received the Bradley Stoughton Teaching
Award (ASM) in 1956, and the Grossman (ASM), and Curtis-Mcgraw (ASEE) research awards
in 1966. He is a Fellow of numerous scientific societies. In recognition of these achievements,
Professor Thomas was elected to both the National Academy of Sciences (1983) and the
National Academy of Engineering (1982). Professor Thomas, born in South Wales, UK, is also
a former rugby and cricket player (member, MCC), enjoys skiing and grand opera.
The editors thank the speakers at the symposium and the authors of the scholarly contributions
presented in this volume. A special gratitude is expressed to Prof. .S Suresh for having enabled
the publication of this volume by Elsevier. All royalties from the sale of this book are being
donated to the TMS/AIME and ASM societies for the establishment of an award recognizing
excellence in Mechanical Behavior of Materials.
November, 2003
Curriculum Vitae of Professor Thomas
Date and Place of Birth: 9 August 193M2a,e steg, Glamorgan, U.K.
Academic Qualifications
B.Sc. with First Class Honors in Metallurgy, University of Wales (Cardiff), 1952.
Ph.D. University of Cambridge, 1955; Sc.D. University of Cambridge, 1969.
Career Details
1956-59 ICI and .tS Catharine's College Fellow, University of Cambridge
0691 Visiting Assistant Professor, University of California, Berkeley
1961-Present University of California, Berkeley: Full Professor (1966); Associate Dean,
Graduate Division (1968-69); Assistant to the Chancellor (1969-72); Acting
Vice Chancellor, Academic Affairs (1971-72); Chairman, Faculty of the College
of Engineering (1972-73); Senior Faculty Scientist, Materials Sciences Division,
LawreBnecrek eley Laboratory; Founder Scientific Director, and National Center
for Electron Microscopy, LawrencBee rkeley Laboratory (1981-93); on special
leave sa Director, Technology Transfer Centre, Hong Kong University of Science
and Technology, Kowloon, Hong Kong (1993-94); Professor in the Graduate
School, University of California, Berkeley (1995-present).
Awards and Honors
3002 Silver Medal in honor of Prof. .C .S Barrett, ASM Intl. Rocky MountainC hapter
2003 Acta Materialia Gold Medal
1002 First Albany Int. Distinguished Lecture in Mat. Sci. & Eng. (RPI).
iiv
iiiv mulucirruC vitae of Professor samohT
1002 American Society for Materials International, Gold Medallist
9991 Doctorate honoris causa, University of Krakdw, Poland
8991 Honorary Member, Japan Institute of Materials
6991 Honorary D.Sc., Lehigh University, Bethlehem, PA, USA, 1996
6991 Honorary Member, Indian Institute of Metals
6991 Honorary Member, Korean Institute of Metals and Materials
6991 Alexander yon Humboldt Senior Scientist Award, IFW, Dresden, Germany
5991 The Berkeley Citation for Distinguished Achievement, .U .C Berkeley
4991 Honorary Member, Mat. Res. Soc. of India
4991 Medal of Academy of Mining and Metallurgy, Polish Acad. of Sciences, Krakow
1991 Albert Sauveur Achievement Award (ASM International)
7891 I-R 001 Award, Research and Development Magazine
7891 Elected, Fellow, Univ. Wales, Cardiff, UK
7891 Henry Clifton Sorby Award, International Metallographic Society
5891 Honorary Professorship-Beijing University of Science & Technology
3891 Confucius Memorial Teaching Award, Republic of China (Taiwan)
3891 Elected to the National Academy of Sciences, U.S.A.
2891 Elected to the National Academy of Engineering, U.S.A.
1891 Alexander von Humboldt Senior Scientist Award, Max Planck Institute, Stuttgart
0891 EMSA Distinguished Scientist Award for Physical Sciences
9791 Fellow, Metallurgical Society of AIME
8791 Ernest .O Lawrence Award (U.S. Department of Energy)
7791 The Rosenhain Medal (The Metals Society, U.K.)
6791 Fellow, Royal Microscopical Society, U.K.
6791 Fellow, American Society for Metals
3791 Visiting Professor at Nagoya University, Japan Society for Promotion of Science
1971-72 Guggenheim Fellow; Visiting Fellow, Clare Hall, Cambridge University
6691 Curtis-McGraw Research Award (American Society for Engineering Education)
6691 Grossman Publication Award (American Society for Metals) for paper "Structure
and Strength of Ausformed Steels", Trans. ASM, ,85 365 (1965)
5691 Bradley Stoughton Teaching Award, American Society for Metals
4691 Miller Research Professor, UC Berkeley
3591 National Undergraduate Student Prize, Institute of Metals (London)
Professional Activities
1998- Managing Director, Acta Metallurgica, Inc. Board of Governors
1995-98 Editor in Chief, Acta Materialia and Scripta Materialia
2991 Founder Member, Editorial Board, NanoStructured Materials (Elsevier)
1991-95 Vice President, International Federation of Societies for Electron Microscopy
1986-90 President, International Federation of Societies for Electron Microscopy
1974-86 Secretary General, International Federation of Societies for Electron Microscopy
1991-94 Reappointed, Member, Board of Governors Acta Metallurgica, Inc.
1987-88 Member, SU Department of Energy .E .O Lawrence Award Selection Committee
1982-85 Chairman, Acta Metallurgica, Inc. Board of Governors
1985-90 Member, Acta Metallurgica, Inc. Board of Governors
mulucirruC vitae of rosseforP samohT xi
1978-81 TMS-AIME Board of Directors
5791 President, Electron Microscopy Society of America
1972-73 UC Convenio Program, Visiting Professor, University of Chile, Santiago, Chile
1961-present Served on many national and international committees including National
Research Council (USA), International Federation of Electron Microscopy
Societies, EMSA, ASM, TMS, University of California, editorial boards, etc.
Served on science and technology boards (Taiwan, Singapore, Korea, South
Africa and Mexico) as materials advisor.
Publications Over 550 papers, 2 books, numerous book chapters.
Selected Publications
.1 "Structure-Property Relations: Impact on Electron Microscopy," in Mechanics and Materials:
Fundamentals and Linkages, Marc A. Meyers, Ronald W. Armstrong and Helmut
Kirchner, eds. New York: .J Wiley & Sons, 1999, pp. 99-121; LBNL 40317.
.2 "Nd Rich Nd-Fe-B Tailored for Maximum Coercivity," Er. Girt, Kannan M. Krishnan,
G. Thomas, C. J. Echer and Z. Altounian, Mat. Res. Soc. Symp. Proc. 577, Michael Coey
et al., eds. Warrendale, PA: The Materials Research Society, 1999, pp. 247-252.
.3 "Some Relaxation Processes in Nanostructures and Diffusion Gradients in Functional
Materials," G. Thomas, in Deformation-Induced Microstructures: Analysis and Relation to
Properties (Proc. 20th Ris~ International Symposium on Mat. Sci.,), .J B. Bilde-S~rensen,
.J V. Carstensen, N. Hansen, D. Juul Jensen, T. Leffers, W. Pantleon, .O B. Pedersen and
G. Winther, eds., Ris~ National Laboratory, Roskilde, Denmark, 1999, pp. 505-521.
.4 "Origin of Giant Magnetoresistance in Conventional AlNiCo 5 Magnets," A. Htitten,
G. Reiss, W. Saikaly and G. Thomas, Acta Materialia 49, 827-835 (2001).
.5 "Novel Joining of Dissimilar Ceramics in the Si3N4-A120 3 System Using Polytypoid
Functional Gradients," Caroline .S Lee, Xiao Feng Zhang and Gareth Thomas, Acta Materialia
vol.49, 3767-3773, & 3775-3780 (2001).
See web-site (below) for more details:
Internet: http://www.mse.berkeley.edu/faculty/thomas/thomas.html
Patents
Process for Improving Stress-Corrosion Resistance of Age-Hardenable Alloys, U.S. Patent
3,133,839 (1964).
High Strength, High Ductility Low Carbon Steel .J( Koo and G. Thomas), U.S. Patent
4,067,756 (1978).
High Strength, Tough Alloy Steels .G( Thomas and B. V. N. Rao), U.S. Patent 4,170,497 (1979).
Method of Making High Strength, Tough Alloy Steels (G. Thomas and B. V. N. Rao), U.S.
Patent 4,170,499 (1979).
High Strength, Low Carbon, Dual Phase Steel Rods and Wires and Process for Making Same
(G. Thomas and A. Nakagawa). U.S. Patent 4,613,385 (1986).
x Curriculum vitae of Professor Thomas
Controlled Rolling Process for Dual Phase Steels and Applications to Rod, Wire, Sheet and
Other Shapes .G( Thomas, .J .H Ahn, and .N .J Kim), U.S. Patent 4,619,714 (1986).
Method of Forming High-Strength, Corrosion-Resistant Steel .G( Thomas, .N .J Kim, and
.R Ramesh), U.S. Patent 4,671,827 (1987).
Method of Producing a Dense Refractory Silicon Nitride (Si3N4) Compact with One or More
Crystalline Intergranular Phases .G( Thomas, .S .M Johnson, and .T .R Dinger), U.S. Patent
4,830,800 (1989).
High Energy Product Permanent Magnet Having Improved Intrinsic Coercivity and Method of
Making Same .R( Ramesh and .G Thomas), U.S. Patent 4,968,347 (1990).
Giant Magnetoresistive Heterogeneous Alloys and Method of Making Same .J( .J Bernardi,
.G Thomas, and .A .R Huetten), U.S. Patents 5,824,165 (1998) and 5,882,436 (1999).
Nano and Microstructural Design of Advanced Materials
M.A. Meyers, R.O. Ritchie and M. Sarikaya (Editors)
(cid:14)9 2003 Elsevier Ltd. All rights reserved.
CHARACTERIZATION: THE KEY TO MATERIALS
R. Gronsky
Department of Materials Science & Engineering, University of California
Berkeley, California 94720-1760 USA
ABSTRACT
His seventieth birthday offers this special occasion to recall the many seminal contributions made by Professor
Gareth Thomas to the field of materials science and engineering. A brief reckoning of his career, his
dedication to the development of electron microscopy techniques, his applications of high precision
characterization methods to numerous engineering materials systems, and his successes as both researcher and
educator are recounted here.
INTRODUCTION
The development of advanced materials is guided by assessment at appropriate levels of resolution. This has
always been the preferred protocol, and hallmark, of materials science and engineering. Our discipline seeks to
understand all of the links connecting the synthesis and processing of materials with the evaluation of their
properties, with their performance in engineering applications, and with their internal structure and
composition. However, as modern engineering progresses towards increased complexity and reduced
dimensionality, our discipline places ever higher demands on the diffraction, spectroscopy, and microscopy
techniques used for microstructural analysis.
There was a time when "pearlite" was an acceptable designation for a microstructural constituent associated
with certain mechanical properties of steels. Thirty years ago, it became essential to know the composition of
both the ferrite and the cementite in "pearlite," including whether or not there were any gradients in carbon
concentration at their contiguous interfaces. And as this manuscript is being written, hundreds of scientists
around the world are struggling to sort out carbon nanotubes as single-walled or multi-walled, spiral or
concentric, vacant or filled, with what species, at which specific locations. Consequently, the levels of
resolution appropriate for contemporary materials science and engineering are those that reveal individual
atomic positions in the spatial domain, and individual atomic identities in the temporal or energy domain. It is
now generally accepted that atomic level characterization is the essential key to materials, old and new.
Today's symposium highlights many of the triumphs of advanced materials development based upon this
singular tenet of microstructural design, which has been championed by Professor Gareth Thomas throughout
his long and illustrious career. It was just over thirty (30) years ago that I came to Berkeley to begin my
graduate studies in Professor Thomas's group, and I'm honored to offer this contribution in celebration of his
seventieth (70 )ht birthday.
4 .R Gronsky
BACKGROUND
Gareth Thomas was born on August 9, 1932. He completed his Bachelor of Science degree with First Class
Honors in Metallurgy from the University of Wales, Cardiff, in 1952. Three years later, in 1955, he obtained
his Ph.D. from the University of Cambridge, where he stayed through 1959 as an ICI/St. Catherine's College
Fellow. In 1960 he arrived in Berkeley as a Visiting Assistant Professor and joined the ladder rank faculty as
an Assistant Professor in 1961.
During his first year on the faculty, when other assistant professors seeking tenure were buried in labs or
libraries struggling to solidify their academic careers, Professor Thomas chose instead to organize an
international conference. Securing a prime location on the Berkeley campus, he hosted "The Impact of
Transmission Electron Microscopy on Theories of the Strength of Metals" in 1961, providing an aggressive
examination of the Orowan and Petch equations as well as new insights into the mechanisms of strengthening
by finely dispersed (TEM-sized) obstacles. Many of the luminaries in the fledgling field of transmission
electron microscopy were there (Figure 1), taking note of both the ambition and the dedication their colleague
Gareth Thomas, who would continue this tradition of global congresses to advance the practice of electron
microscopy in applications to engineering materials throughout his career.
Figure :1 A wef of the at the attendees 1691 conference Berkeley no the
"Impact of MET no Theories of eht Strength of Metals." L ot R first
row, R.B. Nicholson, M.J. Whelan, .G Thomas, .J ;nrubhsaW L ot R
second row, .K Melton, .A Kelly, .G P.R. Rothman, .nnawS
Also during his first year on the faculty, Professor Thomas found time to draft and edit a complete textbook,
Transmission Electron Microscopy of Metals, published by Wiley only one year later, in 1962. This treatise
was the first of its kind, a practical, pedagogical, "hands-on" treatment of the transmission electron microscopy
technique, annotated with instructions on how to prepare representative samples worthy of scientific
investigation. It served generations of students for the next 17 years, until his second edition, co-authored with
M.J. Goringe, was released in 1979.
Thomas's early emphasis on high-resolution microstructural characterization of metals was bom of his notable
successes during his time at Cambridge. One of the most perplexing problems of the day was the catastrophic
failure of the Comet aircraft, prompting many investigations into the relationship between the microstructure
and deformation behavior of aluminum-based alloys. Thomas's work [ ,1 2] showed quite clearly (Figure 2) the
occurrence of a precipitate-free zone (PFZ) adjacent to grain boundaries, and a coarser precipitate distribution
adjacent to the PFZ, when compared to the surrounding matrix.
Implicating such inhomogeneities in microstructure as the likely cause for inhomogeneities in mechanical
response, the path forward was revealed through microstructural design. Subsequent development of thermo-
mechanical processing cycles to eliminate the formation of PFZs and their attendant problems was facilitated
by electron microscopy, the only technique with sufficient spatial resolution to verify success.
Professor Thomas developed similar processing methodologies to protect age-hardening alloys against stress-
corrosion cracking (Figure 3), resulting in his first patent [3], also issued within a few short years of his debut
on the faculty.
Characterization: The key to materials 5
Figure :2 precipitation Heterogeneous dna precipitate-free zones (PFZs)
ni ,gM3-nZ6-1A reference after .]2[
t l I !! A:~[ ~-St.~im- ~ .,,n,snre~r^d,a~r~no dor|^ 0tr~f L 42 s'uN I I I I I [ I I I I I I I 1 l
to, I~/I 1 [ ]/[l ,g,,,,~i=,~t--2 n f~4,.~ I ]
~ ......... ;~:,o: ;^:,o,~o ,,:~ ;; ;oo; ......... ,, .
erugiF :3 Plot of average stress corrosion life (days) vs aging time
(hours) for aluminum alloys subjected to step aging process, after
reference [3].
EARLY DEVELOPMENTS
In his quest for precision during diffraction analysis, Professor Thomas became an early advocate for the
technique of Kikuchi electron diffraction [4], which results from an inelastic scattering event that is
subsequently elastically scattered. Thomas and co-workers released a series of publications in the 1960s
explaining the method and demonstrating its superior advantages over conventional (spot) electron diffraction
for precise determination of crystalline orientations. By painstakingly assembling photo collages combining
hundreds of Kikuchi electron diffraction patterns, they also generated "Kikuchi maps" to assist investigators in
navigating reciprocal space. Figure 4 shows one such map for the diamond cubic structure [5], but others were
published for both body-centered cubic [6] and hexagonal close-packed [7] structures.
Diffraction also figured prominently in the analysis of spinodal decomposition, but there was no more
convincing evidence of structural modulation that the images published by Thomas and co-workers [8], Figure
5(a). Coarsening of the spinodally-decomposed product resulted in a square wave compositional profile seen
in Figure 5(b), which was much less obvious, and sometimes completely obscured, in diffraction results.
Thomas was also first to point out that microstructures generated by spinodal decomposition were not
6 R. Gronsky
susceptible to the formation of detrimental PFZs, and he proposed employing spinodal decomposition where
possible in alloy systems with known miscibility gaps as another method of intelligent microstructural design.
Figure :4 Kikuchi pam of eht cibuc-dnomaid erutcurts after (silicon)
reference [5]. ehT pot pole si readily identified by sti four-fold
yrtemmys sa 001, eht retnec mottob pole si ,311 gnitneserper na ralugna
egnar of 2.52 ~ tsew-tsaE semertxe era 201 dna 210 poles, ta 9.63 ~ .trapa
'~ "-~'~ *3"' ~' I
Figure :5 Spinodally desopmoced eF-fN-uC alloy showing )a( early
egats dna )b( later product stage gnitluser within aging from eht yranret
ytilibicsim gap. ehT light esahp si uC ,hcir eht dark ,esahp Ni-Fe .hcir
Yet another method of microstructural analysis pioneered about this time was the application of phase contrast
"lattice" imaging to directly assess the local lattice parameter in close-packed metallic alloys. The resolution
performance of transmission electron microscopes was limited thirty years ago to approximately 0.25 nm,
consequently a two-beam "sideband" imaging method was the only feasible option for extracting phase
contrast, generating images of a single spatial frequency. Figure 6 shows how the technique yielded the
modulation wavelength in a spinodally decomposed Au-Ni alloy, the first such demonstration of its type.
Thomas and co-workers continued to apply lattice imaging to a range of spinodal and ordered alloys during the
late 1970s, coupled to the development of subsidiary analytical techniques such as optical microdiffraction [9].
As specimen preparation procedures for non-metallic materials also improved in Thomas's laboratories, phase
contrast methods yielded new insights into novel polytypoid formation in the non-oxide ceramics. The
example shown in Figure 7 documents the substructure of a beryllium silicon nitride, Be9Si3N10, as alternating
stacking sequences of three layers of BeSiN2 followed by two layers of .2N3eB