高次Multi-phase-fieldモデリングによる粒成長過程の予測

概要

論文の詳細を見る
Multi-phase-field (MPF) modeling with a higher-order term, which can stably analyze the triple junction (TJ) behaviors even with large difference between grain boundary (GB) energies, is proposed for the more realistic grain growth prediction. Grain growth simulations of systems including multiple junctions show that the proposed MPF model can represent the stable TJ behaviors with wider range of GB energies than the conventional model, and well perform the quadruple junction behaviors in agreement with the corresponding theory. Two kinds of GB energy distribution models are employed here, which are based on all of and only low cuspate energies of <110> symmetric tilt GB energy in pure Al by molecular dynamics simulations. Polycrystalline grain growth simulations combining with either GB energy distribution exhibited the large amount of nucleation of low-energy boundaries, which would be quantitatively compatible to the experiments. Also, the unrealistic grain structures were observed around the TJs with large GB energy difference when the former distribution model was used. Thus, this fact suggests that the GB networks should be formed by TJs with smaller GB energy difference to avoid the higher unstable energy state.