After a brief review of the thermodynamics and kinetics of glass formation, the mechanical behavior of metallic glasses will be surveyed using the stress-temperature deformation mechanism map, covering elastic and anelastic deformation, homogeneous and inhomogeneous flow, brittle and ductile fracture, and the effects of structural relaxation. The microscopic basis of plastic deformation is the presence of localized shear transformation zones, the action of which creates a characteristic strain pattern in the surrounding elastic matrix. Deformation experiments on colloidal glasses can be used to identify those zones directly.
Frans Spaepen is the Franklin Professor of Applied Physics in the School of Engineering and Applied Sciences at Harvard University. He obtained his undergraduate degree in metallurgical engineering from the University of Leuven in 1971, and his Ph.D. in applied physics from Harvard in 1975, where he has remained ever since. He has been Director of the Materials Research Science and Engineering Center (1990-1998) and of the Rowland Institute (2002-20013), and Interim Dean of the School of Engineering (2008-09). His research interests span a wide range of experimental and theoretical topics in materials science, such as amorphous metals and semiconductors (viscosity, diffusion, mechanical properties), the structure and thermodynamics of interfaces (crystal/melt, amorphous/crystalline semiconductors, grain boundaries), mechanical properties of thin films, and colloidal systems as models for the study of dynamics and defects in crystals and glasses. Professor Spaepen is a member of National Academy of Engineering.