Effect of grain boundary energy anisotropy in 2D and 3D grain growth process

Phase-field modeling of isotropic and anisotropic grain growth has been performed in 2D and 3D system. The multi order parameter grain growth model is adopted and OpenMP is implemented to enhance the computational efficiency. When the anisotropic grain growth phenomenon occurs, the misorientation distribution function of the low angle grain boundary is increased at the early stage and it converge to the certain value, 0.18 in 2D and 0.24 in 3D. The average numbers of faces of anisotropic grain growth is nearly same as the values of isotropic grain growth, which is 6.0 in 2D and 13.8 in 3D. Keywords: Anisotropic grain growth, Phase-field modeling, Microstructure evolutio

Phase-field simulations of the interaction between a grain boundary and an evolving second-phase particle

© 2015 Taylor & Francis. We performed phase-field simulations to analyse the interaction of a migrating grain boundary with an evolving second-phase particle. It is found that depending on the difference between the interfacial energies of the particle-matrix interface for the two grain orientations involved and the driving force for grain boundary movement, particles with a particle size well above the critical limit can dissolve due to passage of the boundary.status: publishe

Effect of strong nonuniformity in grain boundary energy on 3-D grain growth behavior: A phase-field simulation study

Large-scale phase-field simulations were performed of the evolution of grain structures with nonuniform grain boundary energy. A novel approach is proposed to determine the average grain boundary dihedral angles between the grain faces along triple and quadruple line junctions from 3-D voxel-based microstructures. We examine the effect of grain boundary energy nonuniformity on the distributions of the grain size, number of faces per grain, and dihedral angles between grain faces. We study the effect of the initial grain size distribution on the evolution toward steady state for both nonuniform and uniform boundary energy systems. The steady-state grain size and number of faces distributions remain unimodal under all conditions investigated, whereas the dihedral angle distribution is found to become multi-modal when the ratio R=σ_H⁄σ_L between high and low grain boundary energies lies in the range of 1.39 to 1.81. In addition, when R≈√2 a topological transition is observed from a structure with grain faces meeting at triple lines (which themselves terminate in quadruple points) toward one in which the grain faces meet primarily at quadruple line junctions (ending at compact regions of triple junctions or very short triple lines).status: publishe

Evaluating microstructural parameters of three-dimensional grains generated by phase-field simulation or other voxel-based techniques Evaluating microstructural parameters of three-dimensional grains generated by phase-field simulation or other voxel-base

Abstract The MacPherson-Srolovitz relation expresses the rate of volume change of a grain in a three-dimensional polycrystalline system in terms of microstructural parameters-the mean grain width and the triple line length-as well as isotropic values for the grain boundary mobility and energy. We introduce methods to accurately determine these microstructural measures for grain structures described by a voxel-based microstructure representation, such as those generated by phase-field simulations, Monte Carlo Potts models, or three-dimensional reconstructions of experimentally measured polycrystalline microstructures. We evaluate the mean rate of volume change of grains during a phase-field simulation of grain growth and discuss the results in terms of the MacPherson-Srolovitz relation