The dynamics of grain boundary movement were analyzed, in 2 and 3 dimensions, by developing an atomic jump model. The driving force for such movements was deduced from a decrease, in grain boundary surface energy, due to a reduction in surface area. By considering diffusion-like atomic jumps across the grain boundary, the velocity was found to be described by exp[-1/r], where r was the radius of a curved boundary. The model was used to describe the shrinkage behavior of an isolated spherical particle. When r was large, the simulated shrinkage behavior gave almost the same results as did the usual parabolic law for grain growth. The present model also predicted the existence of a critical temperature at which movement of the grain boundary would cease. The velocity increased, with increasing temperature, until it reached a maximum at a certain temperature. It then began to decrease towards zero, near to the critical temperature.

B.N.Kim: Journal of the Japan Institute of Metals, 1997, 61[6], 507-10