Grain boundary (GB) migration in response to different types of driving forces necessarily is coupled to lattice displacements. Hence, grain boundary migration can be driven by stress and/or produce strain during migration. Mechanistically, this is related to the motion of a fundamental type of line defect that is constrained to GBs; these defects, known as disconnections, have both dislocation and step character. This presentation attempts to unify a broad range of GB phenomena through crystallography, statistical mechanics, atomistic simulation, and by comparison with several different experimental observations. I will attempt to unify the concepts of GB shear coupling, GB sliding, grain rotation and the morphology of evolving grain boundaries.
David Srolovitz is the author of ~500 papers on topics in materials theory and simulations ranging from defects (surfaces, grain boundaries, dislocations, point defects), microstructure evolution (grain growth, dislocations, stress effects, phase transformations), deformation (nanomaterials, dislocation motion, creep), and film growth (sputtering, evaporation, CVD) and has an h-index of ~90 (Google Scholar) with ~30,000 literature citations. He is a Member of the US National Academy of Engineering, Fellow of MRS, TMS, ASM, Institute of Physics and is the winner of the 2013 MRS Materials Theory Award. Srolovitz did his undergraduate work in Physics at Rutgers University and PhD from the University of Pennsylvania. He was a staff member at Exxon Corporate Research and Los Alamos National Laboratory early in his career and then professor at the University of Michigan (Materials Science and Applied Physics), Princeton University (Mechanical and Aerospace Engineering, Applied Mathematics). He also served as the Executive Director of the Institute of High Performance Computing and the Scientific Director of the Science and Engineering Research Council in Singapore. He is currently the Bordogna Professor of Engineering & Applied Science and Director of the Penn Institute for Computational Science at the University of Pennsylvania and Chair Professor and Senior Fellow of the Institute for Advanced Study at City University of Hong Kong.