ALI S. ARGON (1930-2019)

BY LALLIT ANAND

ALI SUPHI ARGON, Quentin Berg Emeritus Professor of Mechanical Engineering, Massachusetts Institute of Technology (MIT) — and preeminent world authority on the mechanics of materials — died on Dec. 21, 2019, at his home in Belmont, Massachusetts. His seminal research contributed to our deep understanding of the inelastic deformation and fracture of engineering materials.

Ali was born in Istanbul, Turkey, on Dec. 19, 1930. His father, M.A. Suphi Argon, came from a line of high-ranking military and state officials during the Ottoman Empire days in Turkey. His mother, Seniha Margaret (née Grosche), was born in Berlin, Germany. Ali was educated in Turkey through high school. He pursued his postsecondary studies in the United States, obtaining a B.S. from Purdue University in 1952 and S.M. and Sc.D. degrees from MIT in 1953 and 1956, respectively. His graduate thesis advisor at MIT was the legendary materials scientist, Prof. Egon Orowan (NAS 1969).

After obtaining his doctoral degree, Ali started work at the High Voltage Engineering Corporation of Burlington, Massachusetts, where he worked on Van de Graaff particle accelerators for scientific research and medical applications for two years. In 1958 he returned to Turkey for 18 months of military service in the Turkish Army Ordnance Corps and was discharged with a rank of second lieutenant. During that period, in 1959, he also held a lectureship appointment in the Mechanical Engineering Department of the recently founded Middle East Technical University in Ankara.

Ali returned to the United States in 1960 to accept a faculty appointment in the Mechanical Engineering Department at MIT, where he rose in the ranks from assistant professor to professor by 1968. In 1982, he was appointed to the newly established Quentin Berg Professorship in the department, a position that he held until his retirement in 2001. After his “retirement,” he continued to actively engage in research and student mentorship until 2017.

Ali’s research has been published in premiere technical journals, conference proceedings, and books, with the number of publications exceeding 335 by 2017. He was one of the most widely cited authors on the mechanics of materials in the world.

In his research, Prof. Argon combined pioneering experiments with closely related theoretical and computational modeling efforts aimed at elucidating the fundamental mechanisms of inelastic deformation and fracture of a wide range of engineering materials — including metals and alloys, ceramics, glasses, polymers, and composites. In this domain, his proposal of shear transformations of atomic clusters as the fundamental mechanism of inelastic deformation of amorphous materials, such as metallic glasses, is of primary importance. He mapped out this theory in several highly cited (sole author) papers in the 1970s and continued to expand the understanding of this class of materials with Ph.D. students and collaborators, publishing papers on this topic up to 2008.

Ali also made pioneering contributions to the understanding of plastic deformation and failure in glassy and semicrystalline polymers. Combining experiments, theory, and simulation, his research provided new insights about the rate sensitivity of deformation, texture development, toughening, and failure by crazing. He published more than 70 papers in this area, collaborating with MIT colleagues David M. Parks, Robert E. Cohen (NAE 2010), Ulrich W. Suter, and Mary C. Boyce (who was also his Ph.D. student before joining the MIT faculty; NAE 2012).

The deformation behavior of high-temperature metallic, ceramic, and composite materials was one of Ali’s career-long interests. He developed constitutive models for creep deformation and provided new insights on the evolution of dislocation substructure and the development of damage by creep cavitation in pure metallic materials as well as engineering materials such as stainless steel and superalloys. He also studied the mechanics of creep in directionally solidified eutectic oxides composites. Students and collaborators in this area included Shin Takeuchi, I-Wei Chen, Frank A. McClintock (NAE 1991), Jean Luc Martin, Guenter Gottstein, Tresa M. Pollock (NAE 2005), K.J. Hsia, and David M. Parks.

Other notable research pursuits included the mechanics of ductile fracture, dislocation emission from crack tips and failure by cleavage, and strain hardening in face-centered cubic materials, with Fritz Prinz, Wei Cai, Vasily V. Bulatov, Sidney Yip, Michael Ortiz (NAE 2013), and Derguo Deng.

His most well-known book is Mechanical Behavior of Materials (Addison-Wesley, 1966), with Frank A. McClintock (NAE 1991) and other MIT colleagues. This was one of the first books on the mechanical behavior of not only metals but also ceramics, rubbers, and polymers — all under one cover. Many consider this book to mark the formal beginnings of the modern discipline of mechanics of materials. It laid out the intellectual guidelines and an ambitious agenda for the next 50 years for modern mechanicians to develop a deeper understanding of deformation and fracture of engineering materials through the application of mechanics to microstructure and its evolution.

In addition to this classic book, Ali published two substantial monographs after his retirement that summarized and synthesized his life’s scientific works: Strengthening Mechanisms in Crystal Plasticity (Oxford University Press, 2007) and The Physics of Deformation and Fracture of Polymers (Cambridge University Press, 2013). He was also one of the most sought-after keynote lecturers at national and international conferences. Selected appearances include a University of London Lecture (1979), the K.C.B. McDonald Lecture of the Canadian Metal Physics Society (1985), the Midwest (1985) and the Southwest (2000) Mechanics Lecture Series, the TSM/IMM Lecture (1998), and numerous lectures at Gordon Conferences in a variety of areas.

Ali was a visiting professor of polymer physics at the University of Leeds in the U.K. (1972), a visiting scientist at the Institute for Metal Physics of the University of Göttingen with an Alexander von Humboldt Society Award (1992), and a visiting scientist at the Department of Materials Science and Engineering at Stanford University (1992).

In addition to his scientific research and educational activities, Ali provided substantial service to his profession. He was a member of review committees of national laboratories and university centers, several technical committees of the National Science Foundation, National Research Council, National Materials Advisory Board, National Academy of Sciences, and the National Academy of Engineering (NAE), and he chaired several of these. He served on the board of directors of the Society of Engineering Science and the board of governors of the Institute for Mechanics and Materials. He was a member of the American Physical Society, the Materials Society, the American Society for Metals, the American Society of Mechanical Engineers, the Materials Research Society, and the Society of Engineering Science.

Prof. Argon mentored more than 30 Ph.D. students and numerous postdoctoral researchers at MIT. They have since progressed to faculty positions throughout the United States and abroad and have pursued careers in national laboratories, industries, and consulting. His doctoral students include I-Wei Chen (University of Pennsylvania), Mary C. Boyce (Columbia University), K. Jimmy Hsia (Nanyang Technical University), Tresa Pollock (University of California, Santa Barbara), Vijay Gupta (UCLA), and Michel Demkowicz (Texas A&M University).

Recognition by one’s professional peers is the foremost honor that any person can receive, and Ali received such recognition several times during his career. He was elected to the NAE in 1989. Other major honors include the Charles Russ Richards Memorial Award (1976) and the Nadai Medal of the American Society of Mechanical Engineers (1998); the Staudinder Durrer Medal of the ETH of Zurich, Switzerland (1999); Distinguished Life Membership in the Sigma Alpha Mu (International Professional Society of Materials and Engineering) (2000); the Heyn Commemorative Medal of the German Materials Society (Deutsche Gesellschaft fur Materialkunde) (2004); the U.S. Senior Scientist Award of the Alexander von Humboldt Society of Germany (1992) for research in Germany; and the Outstanding Mechanical Engineer Award from Purdue University (2004). He was awarded fellowships from the American Physical Society (1987) and the International Conferences of Fracture (1983), and he received an honorary doctorate of engineering from Purdue University (2005).

Finally, the high honor and regard in which Ali was held by those who knew him as both a teacher and a colleague are reflected in the following brief quotes:

•   Mary Boyce writes, “What an impactful career and life he had — and how incredible he was as a mentor and friend to me. I am at a loss for words — I am sure the same is true for all of us.” 
•  Tresa Pollock writes, “We have lost a giant — a tremendous scholar, leader, mentor, and friend. He will be missed but his impact and contributions will be with us for a long time to come.”
•   Robert Ritchie (UC Berkeley, NAE 2001) writes, “Ali was a truly wonderful person and a spectacular force in the field. Moreover, he was one of the few people who kept me sane when I was at MIT! The world is poorer for his passing.”
•  James Rice (Harvard University, NAE 1980) writes, “Ali would seem to be the last of the great, already legendary, MIT professors in domains fascinating to me, who I had started to know and admire first as a grad student at Lehigh and later as a junior faculty member nearby at Brown, and had, of course, the pleasure of knowing yet more closely after moving to Cambridge nearly four decades ago.”

Ali is survived by his wife, Xenia (née Lacher) Argon, a poet, and their son, Kermit Argon, an environmental biologist. Ali and Xenia also had a daughter, Alice, an astrophysicist at the Harvard Smithsonian Astrophysical Observatory, who passed away at a young age in December 2015. Ali’s family can be very proud of his long-lasting contributions to — and direction setting of — the discipline of mechanics of materials.