Correlation between the Structure, Energy, and Local Elastic Properties of Grain Boundaries in Metals

摘要

The zero-temperature energies and equilibrium volume expansions of point-defect free asymmetrical grain boundaries (GBs) involving the four densest planes in fcc bicrystals (with some higher-index plane on the other side of the interface) have been determined using an embedded-atom-method potential fitted to Au. It is found that the two asymmetrical tilt GBs at the endpoints of the related GB energy vs twist disorientation curves give rise to pronounced energy cusps. As for symmetrical GBs, a practically linear relationship between the GB energy and equilibrium volume expansion is observed. The volume expansion and the destruction of the perfect-crystal stacking at the GB are shown to cause a pronounced local decrease in the resistance toward shear parallel to the GB plane. 21 refs., 5 figs. (ERA citation 14:024668)