Modeling the topological features during grain growth by cellular automaton

A two dimensional cellular automaton model, with advanced features for continuous tracking and precise estimation of curvature of grain boundary, has been developed to simulate and study the topological and kinetic features of grain growth in polycrystalline materials. The model simulations exhibited experimentally observed topological arrangements of grains as well as validated the two independently derived grain growth kinetics models, namely, Burke and Turnbull's parabolic law and von Neumann-Mullins law for the growth rate of individual grains. Furthermore, the model was used to study the growth kinetics in graded and columnar microstructures. The growth kinetics was found to depend on the extent of gradation and the aspect ratio of columnar grains. it was observed that both the graded and columnar microstructures evolve towards the equiaxed microstructure during the grain growth. (C) 2009 Elsevier B.V. All rights reserved.