COMPUTER-SIMULATION OF TOPOLOGICAL EVOLUTION IN 2-D GRAIN-GROWTH USING A CONTINUUM DIFFUSE-INTERFACE FIELD MODEL

The local kinetics and topological phenomena during normal grain growt h were studied in two dimensions by computer simulations employing a c ontinuum diffuse-interface held model. The relationships between topol ogical class and individual grain growth kinetics were examined, and c ompared with results obtained previously from analytical theories, exp erimental results and Monte Carlo simulations. It was shown that both the grain-size and grain-shape (side) distributions are time-invariant and the linear relationship between the mean radii of individual grai ns and topological class n was reproduced. The moments of the shape di stribution were determined, and the differences among the data from so ap froth, Potts model and the present simulation were discussed. In th e limit when the grain size goes to zero, the average number of grain edges per grain is shown to be between 4 and 5, implying the direct va nishing of 4- and 5-sided grains, which seems to be consistent with re cent experimental observations on thin films. Based on the simulation results, the conditions for the applicability of the familiar Mullins- Von Neumann law and the Hillert's equation were discussed. Copyright ( C) 1997 Acta Metallurgica Inc.