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Materials Science and Engineering A 438–440 (2006) 2–11

Morris Cohen: A memorial tribute

G.B. Olson ∗Northwestern University and QuesTek Innovations LLC, Evanston, IL 60208, USA

Received 16 July 2005; received in revised form 3 January 2006; accepted 5 February 2006

bstract

The following is the text of an oral presentation delivered at the opening of ICOMAT ’05 in Shanghai on 14 June 2005 in memory of the lateorris Cohen, senior leader of the materials discipline and the science of martensite.2006 Elsevier B.V. All rights reserved.

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eywords: Martensite history; Mechanism; Kinetics

. Introduction

We lost a great Man of Martensite two weeks ago. It was myreat privilege to work closely with Morris Cohen for almost0 years and to benefit from his frequent advice for another0 thereafter. I hope to convey some sense of the scope of hisontributions as a Statesman, a Philosopher, a Scientist, and aumanist. But first for the context of this special ICOMAT, Iould like to say something about his special relationship withhina.

On the occasion of his retirement from research, Profes-or Cohen remarked that his very first and very last graduatetudents were both Chinese. I believe it was special relation-hips formed early in his career, which caused a longing toeconnect with Chinese colleagues, that were behind the greatxcitement he showed when he was able to visit China forhe first time in 1980 (Fig. 1). The photo records his meetingith Professor Hsu here in Shanghai during that visit. His visitas in association with a delegation of U.S. metallurgists orga-ized by the late John Tien that led to a TMS publication ofMetallurgical Treatises.” [1] Professor Cohen was a consum-ate teacher and writer. As part of that monograph, he wrote a

eview on martensite with Professor Marv Wayman [2] where hexpressed our ideas on martensite nucleation in his own words,

ar more clearly than anything I could write myself. To thisay I use that text to introduce my own students to what I amrying to tell them about martensite. I recall Professor Cohen’s

∗ Tel.: +1 847 491 2847; fax: +1 847 491 7820.E-mail address: g-olson@northwestern.edu.

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xcitement upon his return from China, when he held a din-er party at his home to tell us all about the wonders he hadeen.

A person Professor Cohen had a special fondness for washe man we all knew at MIT as “Chester” Shih, shown hereFig. 2) at an ancient astronomical observatory in Beijing duringrofessor Cohen’s next visit in 1985. The broadest smile came

o his face when Professor Cohen spoke of Dr. Shih and allis achievements. I believe it was the next year at ICOMAT86 in Nara that Professor Cohen first encouraged the Chineseelegation to consider hosting an ICOMAT. In one of our moreecent conversations, he expressed his delight that the ICOMATe had encouraged was now becoming a reality.

. Scientist/statesman

Professor Cohen received several honorary degrees from aca-emic institutions around the world (Table 1). His academicositions notably included Honorary Professorships at both theeijing University of Science and Technology and the Beijing

nstitute of Aeronautics and Astronautics, both awarded duringis first visit to China in 1980.

Professor Cohen was born and raised in Chelsea, Mas-achusetts, near Boston, and received all his university educationt MIT. He had planned to return to the family business in type-etting metals, but MIT faculty came to his home and convincedis parents that the world would be better served by his pursuing

n academic career.

His memberships in learned societies (Table 2) included bothhe National Academies of Science and Engineering. Of hisational appointments he is best known for his role as the Chair-

G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11 3

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Table 1Academic achievements

Academic degrees

• Bachelor of Science in Metallurgy, MIT, 1933• Doctor of Science in Metallurgy, MIT, 1936• Doctor of Technology (hon.), Royal Institute of Technology, Sweden, 1977• Doctor of Science in Technology (hon.), Israel Institute of Technology,

Israel, 1980• Doctor of Engineering (hon.), Colorado School of Mines, 1985• Doctor of Science (hon.) Northeastern University, 1989

Academic positions• Assistant Professor of Metallurgy, MIT, 1937• Associate Professor of Metallurgy, MIT, 1941• Professor of Physical Metallurgy, MIT, 1946• Ford Professor of Materials Science and Engineering, MIT, 1962• Institute Professor, MIT, 1975• Institute Professor Emeritus, MIT, 1982 to date• Honorary Professor, Beijing University of Science and Technology, 1980

to date• Honorary Professor, Beijing Institute of Aeronautics and Astronautics,

1980 to date

Table 2Professional leadership

Governmental and national appointments

Fig. 1. Professor Morris Cohen with Professor T.Y. Hsu in Shanghai, 1980.

an of the National Academy Study of Materials Science &ngineering, known as the COSMAT study (Fig. 3). Upon hislection to the National Academy of Science, he requested suchstudy to bring clearer national recognition to the emergingaterials field. Eventually his request was granted, subject to

he condition that he chair it himself. He took this assignmentery seriously and put tremendous energy into the study. Firstublished in 1974, the COSMAT report is widely acknowledgeds defining the modern field of materials science and engineer-

ig. 2. Professor Morris Cohen with Professor C.H. Shih in Beijing, 1985.

• Associate Director of Manhattan Project, MIT• Official Investigator, Office of Scientific Research and Development• Consultant, U.S. Atomic Energy Commission• Consultant, U.S. Department of Defense• Member, Materials Research Council, Defense Advanced Projects Agency• Member, National Materials Advisory Board• Chairman, National Academy of Sciences Survey on Materials Science

and Engineering• Member, Advisory Council, National Aeronautics and Space

Administration• Member, Board of Assessment of National Bureau of Standards Programs,

National Research Council• Member, Steering Committee, National Research Council Study of

Materials Science and Engineering• Co-chairman, National Science Foundation Study on Atomic Resolution

Microscopy

Memberships in learned societies• National Academy of Sciences• National Academy of Engineering• American Academy of Arts and Sciences• Indian National Science Academy• New York Academy of Sciences• Federation of American Scientists (Sponsor)• American Association for the Advancement of Science (Fellow)• ASM International (American Society for Metals) (Fellow, Honorary

Member, Past President)• The Metallurgical Society of AIME (Past Chairman of the Institute of

Metals, Fellow, Honorary Member)• Japan Institute of Metals (Honorary Member)• Japan Iron and Steel Institute (Honorary Member)• British Metals Society (Honorary Member)• Korean Institute of Metals (Honorary Member)• Indian Institute of Metals (Honorary Member)• American Physical Society• American Society for Engineering Education• International Society for Stereology• Research Society of North America (Sigma Xi)• Materials Research Society

4 G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11

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ocstime, it acknowledged an often “turbulent” interaction between

Fig. 3. COSMAT repor

ng for the first time, resulting in broad impact on its subsequentvolution [3,4]. The report went well beyond describing the fields it was, to provide a vision of what it could become. Mor-is Cohen’s vision went beyond mere technology to a view ofesponsible technology. Building on the systems view of materi-ls proposed by the late Cyril Stanley Smith, the COSMAT report

ighlighted the complex systems interactions among materi-ls, other technologies, and the environment. As symbolized byhe well-known logo of the “total materials cycle,” COSMATcknowledged the central role of materials in the environmental

Fig. 4. COSMAT representation of structure o

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al materials cycle” [3].

mpact of other technologies, identifying a profound opportunityor our discipline.

The COSMAT study identified the four primary elementsf materials science and engineering: structure, properties, pro-essing, performance, and their relation to both scientific under-tanding and societal need. Representing the field as it was at the

f materials science and engineering [3].

cientific and empirical knowledge (Fig. 4). A more “stream-ined” approach to the interaction between science and engi-eering can be achieved by a linear three-link chain structure for

G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11 5

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Table 3Awards received

• Henry Marion Howe Medal, American Society for Metals (ASM), 1945and 1949

• Albert Sauveur Memorial Award, Boston Chapter, ASM, 1947• Institute of Metals Award, American Institute of Mining, Metallurgical,

and Petroleum Engineers (AIME), 1950• Kamani Gold Medal, Indian Institute of Metals, 1952• Robert Franklin Mehl Award, AIME, 1957• Champion Mathewson Gold Medal, AIME, 1959• Clamer Medal, Franklin Institute, 1959• Gold Medal, ASM, 1968• Gold Medal, Japan Institute of Metals, 1970• La Medaille Pierre Chevenard, Societe Francaise de Metallurgie, 1971• James R. Killian Faculty Achievement Award, MIT, 1974• Procter Prize, Research Society of North America (Sigma Xi), 1976• National Medal of Science, Presidential Award, 1977• Albert Sauveur Achievement Award, ASM, 1977• Joseph R. Vilella Award, American Society for Testing and Materials, 1979• Hobart M. Kramer Award, Lehigh Valley Section, American Ceramics

Society, 1981• Acta Metallurgica Gold Medal, 1981• New England Award, Engineering Societies of New England, 1986• Leadership Award, The Metallurgical Society of AIME (TMS-AIME),

1986• Albert Easton White Distinguished Teacher Award, ASM, 1987• Kyoto Prize in Advanced Technology, 1987• Charles S. Barrett Award, Rocky Mountain Chapter, ASM, 1988• National Materials Advancement Award, Federation of Materials Societies,

1988• David Turnbull Lecture Award, Materials Research Society, 1993•

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ig. 5. Three link chain model for structure of materials science and engineering5] based on Morris Cohen’s “reciprocity” between the cause/effect logic ofcience and goal/means logic of engineering [4].

he four elements, exploiting what Morris Cohen termed a “reci-rocity” between the deductive cause/effect logic of science andhe inductive goal/means relations of engineering (Fig. 5). Heften questioned the dominance of reductionist analysis in thehysical sciences, advocating instead a more holistic contextualnalysis motivated by societal need. Using structure/propertyelations as an example, we are typically taught to regard prop-rties as controlled by structure. Morris Cohen observed thate can equivalently regard structure as controlled by properties,

or our perception of particular aspects of complex structure ischieved by interrogating structure from the perspective of par-icular properties we value, thereby achieving useful understand-ng. The extension of this philosophy to the interaction of all fourlements of materials science and engineering has formed theoundation of the emerging discipline of materials by design [5].

Morris Cohen was likely the most highly decorated materialscientist in history, his numerous awards notably including bothhe National Medal of Science and the Kyoto Prize in Advancedechnology (Table 3). In addition to the many awards is a longer

ist of Distinguished Lectures delivered internationally, notablyncluding international steel conference keynote lectures givenn Beijing in 1985 and 1990 (Table 4).

His many publications cover a broad array of topics, but cen-er strongly on the subject of martensite (Table 5). While hes most widely known for his role as senior statesman of the

aterials field through the COSMAT study, his highest awardspecifically cite his scientific contributions in the field of marten-itic transformations.

Of his honorary doctoral degrees, that of the Royal Institutef Technology in Stockholm, Sweden, had the special signifi-ance that it was awarded in the Stockholm City Hall where theobel Prizes are given (Fig. 6). Morris Cohen considered him-

elf an engineer and was somewhat startled to be admitted intohe National Academy of Science before the National Academy

f Engineering. As engineers are not eligible for the Nobel Prize,is awards of the National Medal of Science and the Kyoto Prizeepresent the highest honors to which an engineer can aspire.

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J. Herbert Hollomon Award, Acta Metallurgica, 1995

During his award of the National Medal of Science by Presi-ent Carter (Fig. 7), his citation for work on “martensitic trans-ormations and the strengthening of steel” was read aloud, tohich the President commented to him, “We need more of that.”e was probably referring to steel, but back home we all took it

s an official presidential endorsement of martensite.To put Morris Cohen’s science in context, it is appropriate to

rovide a context for martensite. In the history of human thought,he separation of metals from ores had a profound impact onrinciples of major religions. Almost as ancient, and almost asystical, was the phenomenon of the quench hardening of steel.

n writing of its history [6], Cyril Smith pointed out that dur-ng the evolution of modern science, great minds such as Reneescartes and Sir Robert Hooke pondered this subject, and actu-

lly had some pretty good ideas by modern standards. A centurygo it became clear that the core of this phenomenon was thetructural transformation we now know as martensite. The chal-enge of martensite attracted some of the most creative mindsn materials science. I believe it is no accident that the intel-ectual leadership of the materials field has traditionally beenisproportionately drawn from the martensite community, forhich Morris Cohen is a prime example. Further, the core ofgeneral science of all materials centers on dynamic, multi-

evel microstructure, the principles of which are most clearly

xpressed in the theory of solid-state first-order phase transfor-ations, amongst which martensitic transformations enjoy theost rigorous foundation.

6 G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11

Table 4Distinguished lectures

• Edward deMille Campbell Lecture, ASM, 1948• Institute of Metals Lecture, AIME, 1957• Burgess Memorial Lecture, Washington Chapter, ASM, 1958• Sauveur Memorial Lecture, Philadelphia Chapter, ASM, 1959• Woodside Lecture, Detroit Chapter, ASM, 1959• Coleman Lecture, Franklin Institute, 1960• Houdremont Memorial Lecture, International Institute of Welding, 1961• Henry Marion Howe Memorial Lecture, AIME, 1962• Hatfield Memorial Lecture, Cleveland Chapter, ASM, 1962• Rockwell Memorial Lecture, Hartford Chapter, ASM, 1965• Opening Lecture, International Conference on the Strength of Metals and

Alloys, 1967• Japan Institute of Metals Lecture, 1970• Opening Lecture, International Conference on the Science and Technology

of Iron and Steel, 1970• Robert S. Williams Lectures, MIT, 1970• Plenary Lecture, American Institute of Chemical Engineers, 1974• Jacob Kurtz Memorial Lecture, Israel Institute of Technology, 1975• Office of Naval Research Anniversary Lecture, 1976• Procter Lecture, Research Society of North America (Sigma Xi), 1976• George A. Miller Visiting Lecture, University of Illinois, 1976• Alpha Sigma Mu Lecture, American Honorary Metallurgical Society, 1978• Honorary Member Lecture, Japan Institute of Metals, 1978• Honorary Guest Lecture, Korean Institute of Metals, 1979• Opening Lecture, International Conference on Martensitic

Transformations, 1979• Nelson W. Taylor Lectures; Pennsylvania State University, 1980• Maseo Yukawa Memorial Lecture, Japan Iron and Steel Institute, 1981• Distinguished Lectureship in Materials and Society, ASM and

TMS-AIME, 1982• New Mexico Distinguished Lecture on Frontiers in Materials

Technologies, 1983• Keynote Lecture, International Conference on High-Strength, Low-Alloy

Steels, Beijing, 1985• Opening Lecture, Conference on Rapidly Solidified Crystalline Alloys,

TMS-AIME, 1985• Second Burgess Memorial Lecture, Washington Chapter, ASM, 1986• Molecular Science Lecture, University of Southern Illinois, 1986• Materials Science Distinguished Lecture, Office of Naval Research and

Naval Research Laboratory, 1986• Memorial Lecture, International Conference on Martensitic

Transformations, 1986• Materials Science and Engineering Distinguished Lecture, University of

Texas at Austin, 1986• Kyoto Prize Lecture in Advanced Technology, 1987• Charles S. Barrett Lecture, Rocky Mountain Chapter, ASM, 1988• Plenary Lecture, International Symposium on Advanced Materials and

Issues of Science/Technology Policy (Japan), 1989• Inland Steel Lecture, Northwestern University, 1990• Gilbert R. Speich Lecture, Chicago Chapter, ASM, 1990• Plenary Lecture, International Conference on High-Strength Low-Alloy

Steels (China), 1990• Opening Lecture, First National Congress of Materials Science (Mexican

•

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Table 5Publications

Category Number ofpublications

Phases and Phase Relationships 13Thermodynamics 10Diffusion 20Phase Transformations: General 12Nucleation and Growth 22Austenite Decomposition, Martensitic

and Displacive Transformations57

Aging and Tempering 35Rapid Solidification 17Interfaces and Grain Boundaries 8Plastic Flow, Strength and Fracture 32Structure/Property Relationships 29Educational, Professional, Policy 34Experimental Techniques 9

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tiMtributed more than any other individual. In this enterprise hewas helped by a large team of researchers under his leader-ship, notably including Machlin in the late 1940’s, Kaufman in

Academy of Materials Science), 1991David Turnbull Lecture, MRS, 1994

A half century ago, that foundation began with the rigorousheory of the invariant-plane-strain crystal kinematics of marten-itic transformations, triggering a large volume of research on

hat subject. Morris Cohen recognized the importance of thatnderstanding (and I recall his clear detailed exposition of it inhe undergraduate classes he taught), but also recognized as anngineering scientist that it is the mechanism and kinetics of

FT

otal papers and edited books 298

he transformation that are most closely related to the behav-ors we exploit to meet societal needs. It is in this domain that

orris Cohen through his long and distinguished career con-

ig. 6. Morris Cohen receiving honorary doctorate from The Royal Institute ofechnology, Sweden, presented in Stockholm City Hall, 1977.

G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11 7

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[cMsbthe saddle point energy barrier, demonstrating that homogeneousnucleation is not possible at the Ms temperature. Qualitative con-sideration (Fig. 12) of the elastic interaction of such an embryowith the dislocation defect of the “reaction path” model sug-

ig. 7. Morris Cohen receiving National Medal of Science from Presidentarter, 1977.

he 1950’s, Raghavan in the 1960’s, and it was my privilege touild on their work assembling the final pieces in the 1970’s and980’s. I would like to next give a brief account of the evolu-ion of Morris Cohen’s ideas of the mechanism and kinetics of

artensitic transformations.From the viewpoint of dislocation dynamics, it was never

articularly surprising that glissile interfaces could achieve veryigh velocities during martensitic growth. It was therefore thehenomenon of martensitic nucleation pacing the overall evolu-ion of transformation that received the most theoretical scrutinynd stood as the most controversial subject in the martensiteeld. Representing Morris Cohen’s very first ideas about marten-itic nucleation, the 1949 “Reaction Path” model of Cohen,

achlin and Paranjpe [7] used the then very new concept of dis-ocations to model the heterogeneous nucleation of martensiteFig. 8). Considering the interaction of a short wall of discrete lat-ice dislocations with a rectangular slab of adjacent material, anddopting strain as the transformation order parameter, consider-tion of the strain field versus distance from the defect identifiedsignificant volume of material with a configuration interme-

iate between the two lattices; this highly distorted volumeas termed a “strain embryo.” Considering lattice deformation

nergy density versus strain in a manner similar to Landau the-ry (Fig. 9), and recognizing the energy density maximum wouldiminish with increasing transformation driving force (depth ofhe second energy well), it was proposed that a local instabil-ty could occur at a critical driving force to yield a martensiticucleus. This concept of “localized lattice instability” at a defectas revisited by Clapp and others in the 1970’s, couched in theewer language of soft phonons, but corresponding to the samehysics as the “reaction path” model of 1949.

Recognizing the distributed nature of heterogeneous defects,achlin and Cohen [8] added the concept of a potency dis-

ribution of nucleating defects, where the number density ofctive sites continuously increases with increasing transforma-

ion driving force (Fig. 10). This has remained a central conceptf quantitative martensite kinetic theory today [9].

With the semicoherent IPS character of martensitic transfor-ations formally established in the 1950’s, Kaufman and Cohen

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ig. 8. (a) Rectangular volume of material interacting with a set of lattice screwislocations denoted by heavy lines; (b) distribution of strain (θ) vs. distanceormal to dislocations [7].

10] recognized that a martensitic nucleus would have to be semi-oherent under the thermodynamic conditions operating at the

s temperatures of bulk polycrystals. Detailed modeling of aemicoherent martensite embryo with a lattice-invariant sheary slip (Fig. 11) formed the basis of their famous calculation of

ig. 9. Schematic plot of free energy density vs. strain (θ) for homogeneousattice deformation from parent phase (θ = 0) to martensite (θ = θM), depicted atwo levels of transformation driving force [7].

8 G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11

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Fig. 10. Schematic potency distribution of martensitic embryos and a

ested an interaction energy term mathematically similar to aegative surface energy contribution. This led to the hypothesishat, well above the Ms temperature, the defect would becomenstable with respect to the formation of a locally stabilizedemicoherent classical martensite embryo (Fig. 12a), rather thanhe highly distorted “strain embryo,” and that such “pre-existingmbryos” could attain sizes equivalent to the homogeneous crit-cal nucleus size (Fig. 12b). An “operational nucleation” eventt Ms then corresponds to the growth startup of these embryos.ather than embryo-scale heterophase fluctuations, the role of

hermal fluctuations in isothermal martensitic transformationsould be to overcome finer scale energy barriers (Fig. 12c)

nvolved in the process of interfacial motion. More rigorousalculations by Olson and Cohen [11,12] in the 1970’s and980’s used a detailed dislocation description of the embryoFig. 13) incorporating explicit “transformation” or “coherency”artial dislocations (Fig. 13b) accounting for the coherent latticeeformations as well as the “anticoherency” lattice dislocationsFig. 13c) accounting for the lattice-invariant shear. These calcu-

ations confirmed many of the features of the Kaufman–Cohen

odel, including explicit prediction of the formation of thepre-existing” embryos prior to their growth startup at the Msemperature.

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ig. 11. (a) Model of semicoherent martensitic nucleus with array of interfacial disemi-thickness (c) defining saddlepoint homogeneous nucleation barrier (�W*) [10].

ated temperature dependence of required potency for nucleation [8].

The ASM Martensite book [13] published as a tribute to Mor-is Cohen in 1991, and distributed at ICOMAT ’92, included aeview of martensitic nucleation co-authored by Alec Roitburd14]. The key concepts of martensitic nucleation can be sum-arized by a three-dimensional “theory space” (Fig. 14). Therst important variable (X1) is the strain amplitude of a criti-al nucleus, the classical nucleation limit corresponding to fullmplitude, while the “nonclassical” alternative involves a par-ial strain amplitude corresponding to the “strain embryo” ofhe early “reaction path” model. The second variable (X2) is theegree of coherency of the nucleus, with fully coherent (sin-le domain) nucleation possible only at extreme driving forces,ypical lower driving force conditions allowing only semico-erent (IPS) nucleation. The third variable (X3) is the degreef heterogeneity of nucleation determining the level of criticalhermodynamic driving force at with nucleation occurs. Overspectrum of circumstances ranging from bulk polycrystals toanoscale dispersed particles, advances in experiment (includ-ng direct electron microscopy observations of heterogeneous

ucleation and atomic scale interfacial dislocation structures)nd theory (including nonlinear physics of coherent lattice defor-ations) have clarified the conditions under which each of

hese theoretical alternatives operates. While strong defects in

locations; (b) work of martensitic embryo formation (�W) vs. radius (r) and

G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11 9

Fig. 12. Schematic energetics of heterogeneous nucleation with mobility con-trolled kinetics. (a) Energy vs. size at high temperature (T > T0) representingstabilization of martensitic embryos by defect elastic interaction. (b) Homoge-nni

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e(story is vivid because the lesson was learned.

Operating in what may have been the most stressful and chal-lenging environment on the planet, the extraordinary sincerityof Morris Cohen’s caring for others had a remarkable ability to

eous nucleation barrier, identifying critical nucleus size (r*). (c) Homogeneousucleation barrier with superimposed detail representing activation energy fornterfacial motion [10].

ulk polycrystals allow nucleation at low driving forces by therowth startup of pre-existing semicoherent classical embryos,omogeneous nucleation at extreme driving forces in defect-ree nanoscale particles enables fully coherent nucleation withignificant departures from the classical strain amplitude. Withhe quantitative understanding now in hand, it is all the moreemarkable to observe that every one of the key theoretical con-epts in martensitic nucleation first appeared in the innovativeapers of Morris Cohen.

. Philosopher/humanist

In retrospect, the aspect of Morris Cohen that most set himpart was his remarkable humanity. He was a very spiritual per-on who was not only a founder and leader of his local Temple,ut who was also very comfortable expressing his appreciation

f the spirituality of others regardless of faith. In the late 1970’sy wife and I had the privilege of visiting Israel with him under

n exchange program between MIT and Technion (which formedelationships later important in bringing leading martensite sci-

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ig. 13. Martensitic nucleation by dislocation dissociation: (a) nucleatingefect; (b) dissociation of defect to produce “coherency” partial dislocationsf lattice deformation; (c) simultaneous generation of “anticoherency” latticeislocations of lattice-invariant shear [11].

ntists out of the Soviet Union). Although he is not in this photoFig. 15) of the ancient trees in the Garden of Gethsemane out-ide Jerusalem, I know that he was standing beside me at theime. He took me to this special place to educate me. The mem-

ig. 14. Principal parameters defining a “theory space” for martensitic nucle-tion [14].

10 G.B. Olson / Materials Science and Engineering A 438–440 (2006) 2–11

Fig. 15. Ancient trees in Garden of Gethsemane, Jerusalem, 1979.

Fig. 16. Letter to Morris Cohen from 9-year-old girl, 1968.

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Fig. 17. Response letter from

Fig. 18. Morris Cohen, Kyoto Prize photo, 1987.

ring the best out of the people around him. As an example ofhat caring I would like to share a correspondence that his sonoel read at the funeral two weeks ago. At the time of his elec-ion to the National Academy of Science in 1968, Morris Cohen

Morris Cohen, 1968.

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[13] G.B. Olson, W.S. Owen (Eds.), Martensite, ASM, Metals Park, OH,1992.

[14] G.B. Olson, A.L. Roitburd, in: G.B. Olson, W.S. Owen (Eds.), Martensite,

G.B. Olson / Materials Science an

eceived this note handwritten in pencil from a 9-year-old girlFig. 16). His response follows (Fig. 17). I was an undergrad-ate at the time, and the women students he refers to were mylassmates. I know well how busy he was when he took the timeo write to a nine year old.

As comfortable as he was drawing strength from ancient wis-om in the form of traditional religion, Morris Cohen’s essaysn “humanistic materialism” show that he was equally comfort-ble working within the scientific parameters of “testable truth”o improve the human condition in response to the same ideals15]. In these essays he expressed his belief that human beingsan have a significant impact on social evolution by teachingnd living the values they hold sacred, to the benefit of futureenerations they can “help but never know.”

In his teaching and his living, Morris Cohen (Fig. 18) cer-ainly practiced what he preached.

eferences

[1] J.K. Tien, J.F. Elliot (Eds.), Metallurgical Treatises, TMS-AIME Technol-ogy of Metallurgy Series, Warrendale, PA, USA, 1981.

[

ineering A 438–440 (2006) 2–11 11

[2] M. Cohen, C.M. Wayman, in: J.K. Tien, J.F. Elliot (Eds.), MetallurgicalTreatises, TMS-AIME Technology of Metallurgy Series, Warrendale, PA,USA, 1981, p. 445.

[3] M. Cohen, Chairman, Materials and Man’s Needs, Summary Report, NASCommittee on the Survey of Materials Science and Engineering, Washing-ton, DC, 1974.

[4] M. Cohen, Mater. Sci. Eng. 25 (1976) 3.[5] G.B. Olson, Science 288 (2000) 993.[6] C.S. Smith, in: G.B. Olson, W.S. Owen (Eds.), Martensite, ASM, Metals

Park, OH, 1992, p. 21.[7] M. Cohen, E.S. Machlin, V.G. Paranjpe, ASM (1949) 242.[8] E.S. Machlin, M. Cohen, Trans. AIME 194 (1952) 489.[9] M. Lin, G.B. Olson, M. Cohen, Metall. Trans. 23A (1992) 2987.10] L. Kaufman, M. Cohen, Pros. Met. Phys. 1 (1958) 165.11] G.B. Olson, M. Cohen, Metall. Trans. 7A (1976) 1905.12] G.B. Olson, M. Cohen, in: F.R. Nabarro (Ed.), Dislocation in Solids, vol.

7, North-Holland, Amsterdam, 1986, p. 295.

ASM, Metals Park, OH, 1992, p. 149.15] M. Cohen, Metall. Trans. A 14 (1983) 513.