Egon Orowan

Solvay Conference on Physics in Brussels 1951. Left to right, sitting: Crussaro, N.P. Allen, Cauchois, Borelius, Bragg, Moller, Sietz, Hollomon, Frank; middle row: Rathenau,(nl) Koster, Rudberg,(sv), Flamache, Goche, Groven, Orowan, Burgers, Shockley, Guinier, C.S. Smith, Dehlinger, Laval, Henriot; top row: Gaspart, Lomer, Cottrell, Homes, Curien Egon Orowan FRS (2 August 1902 – 3 August 1989) was a Hungarian-British physicist and metallurgist. He was key in introducing crystal dislocation into physics and understanding of how materials plastically deform under stress. According to György Marx, he was one of The Martians, a group of Jews born in Pest between 1890 and 1910 who shaped the 20th century's technology after moving to the West.

Early life Orowan was born in the Óbuda district of Budapest in 1902. After six months of mandatory apprenticeship done home in Hungary, he was admitted to the Technische Hochschule in Charlottenburg (now Technische Universität Berlin), where he studied mechanical and then electrical engineering. roughly contemporarily with G. I. Taylor and Michael Polanyi, realized that the plastic deformation of ductile materials could be explained in terms of the theory of dislocations developed by Vito Volterra in 1905. Though the discovery was neglected until after World War II, it was critical in developing the modern science of solid mechanics.

In Hungary, he seemed to have experienced some difficulty in finding immediate employment and spent the next few years living with his mother and ruminating on his doctoral research. Later, his research interests expanded to include geology. Bingham Medal of the Society of Rheology (1959) Honorary doctor of engineering degree from Technische Universität Berlin (1965)

Orowan died at the age of 87 on 3 August 1989, in the Mount Auburn Hospital in Cambridge, Massachusetts. He was buried in the Mount Auburn Cemetery.

Selected publications

"Zur Temperaturabhängigkeit der Kristallplastizität". Zeitschrift für Physikysik, vol. 102 (1936) 112–118. "The Rate of Plastic Flow as a Function of Temperature". Proceedings of the Royal Society, vol. A168 (1938): 307–310. "Problems of Plastic Gliding". Proceedings of the Physical Society, vol. 52 (1940): 8-22. "Origin and Spacing of Slip Bands". Nature, vol. 147 (1941): 452–454. "A New Method in X-ray Crystallography". Nature, vol. 149 (1942): 355–356. "The Fatigue of Glass Under Stress". Nature, vol. 154 (1944): 341–343. "Fracture and Notch Brittleness in Ductile Materials", in Brittle Fracture in Mild Steel Plates, British Iron and Steel Research Association Part 5 (1945) 69–78. "Creep in Metallic and Non-metallic Materials". Proceeding of the First. U.S. National Congress of Applied Mechanics. New York: ASME, 1953. pp. 453– 472. "Condition of High Velocity Ductile Fracture". Journal of Applied Physics, vol. 26 (1955): 900–902. "Continental Drift and the Origin of Mountains". Science, vol. 146 (1964): 1003–1010. "Dilatancy and the Seismic Focal Mechanism". Reviews of Geophysics, vol. 4 (1966): 395–404. "The Origin of the Oceanic Ridges". Scientific American, vol. 221 (1969): 102–119. "Surface Energy and Surface Tension in Solids and Liquids". Proceeding of the Royal Society, vol. A316 (1970) 473–491.