Effect of second phase mobile particles on polycrystalline grain growth: A phase-field approach

The control of grain size is of great interest to the material science community since the properties and performance of materials are strongly affected by the size of grains. Grain boundary mobility plays a key role in the grain growth process. In this context, grain boundary mobility is strongly influenced by the presence of second phase particles. In this work, we examine the effect of mobile monodisperse second phase particles on the kinetics of polycrystalline grain growth using a phase-field theory. The governing equations for the evolution of the order parameters are obtained from a thermodynamically consistent theory of phase transformations. For each grain and particle, separate phase-field variables are considered. The active parameter tracking (APT) algorithm [S. Vedantam, B.S.V. Patnaik, Phys. Rev. E 73 (2006) 016703] is used for considering the large number of phase-field variables. A bicrystal model with dense particles is examined first, and then extended to polycrystalline simulations. The accuracy of the model was examined by comparing with the Zener relation for limiting mean radius (R) under bar (lim) in 2D grain growth with immobile particles. The results obtained from the model are in very close agreement with the results from literature. (C) 2012 Elsevier B.V. All rights reserved.