Grain Boundary Structure and Its Energy of <110> Symmetric Tilt Boundary in Copper

Abstract

In the present study, grain boundary energy and atomic structure of <110> symmetric tilt boundaries in copper were evaluated by molecular dynamics (MD) simulation. From the simulations, the grain boundary energy of <110> symmetric tilt boundaries depended on misorientation angle and there were large energy cusps at the misorientation angles which corresponded to (111) S 3 and (113) S 11 symmetric tilt boundaries. It was found that the atomic structure of each <110> symmetric tilt boundary was described by the combination of three kinds of structural units which consisted of (331) S 19, (111) S 3 and (113) S 11 symmetric tilt boundaries and two single crystal units which consisted of (110) S 1and (001) S 1 single crystals. From the the analysis of the excess free volume in each grain boundary, it was found that the energy of structural units depended on the excess free volume of the units and that the misorientation dependence of grain boundary energy agreed with that of the free volume in grain boundaries.