SIMULATION OF GRAIN-BOUNDARY MOVEMENT AND INTERACTION WITH SPHERICAL-PARTICLE BY FINITE-ELEMENT METHOD

The axi-symmetric finite element method is developed in order to simul ate 3-dimensional migration behavior of grain boundary around a spheri cal paticle. At first, the method is applied to the simulation of shri nkage behavior of a spherical grain boundary. The spherical grain boun dary shrinks in keeping its original shape, and the velocity is consis tent well with the theoretical prediction, indicating a validity of th e present method. In the simulation of the interaction between curved grain boundary and spherical particle, the velocity of the grain bound ary varies during the interaction process depending on the location fr om the particle. Since the velocity of the grain boundary near the par ticle is higher than that distant from the particle, the shape of the grain boundary is considerably deformed during the interaction. A mini mum migrating velocity occurs at different time depending on the locat ion of the boundary, and on the ratio between the diameter of the part icle and the radius of curvature of the grain boundary. The decrease o f the velocity and the time loss due to the particle-induced pinning i ncreases with increasing particle radius.