Event
ME Seminar: David Srolovitz "Grand Unified Theory of Grain Boundaries"
Thursday, April 27, 2017
11:00 a.m.
DeWalt Seminar Room, 2164 Martin
Teng Li
lit@umd.edu
David Srolovitz, Ph.D.
Joseph Bordogna Professor
Materials Science and Engineering
Mechanical Engineering and Applied Mechanics
Penn State University
"Grand Unified Theory of Grain Boundaries"
Abstract: Grain boundaries do it all. They transmit stresses, they move under the action of an applied stress, they migrate when curved, they slide, they roughen, they transmit/absorb/emit dislocations,… They are central to the mechanical behavior of polycrystalline materials. They behave differently at low temperature and high temperature, with different grain misorientations, with different inclinations,… I will present a bicrystallography-based model for the structure and kinetic properties of grain boundaries that rationalizes many grain boundary properties within a single coherent picture. The model is based on the migration of a type of line defects that only exist in the grain boundary, known as disconnections. Finally, I will review some recent progress in moving from a discrete disconnection-level description of grain boundaries to a continuum model.
