A New Model for Phase-Field Simulation: Grain Growth Under Non-uniform Storage Energy Field Based on SIBM Theory

In this study, a phase-field model for simulating the grain growth of polycrystalline microstructures was developed. Based on the strain-induced grain boundary migration theory, the stored energy field is introduced into the model in a novel form. This approach aims to simultaneously account for the inhomogeneity of deformation-stored energy both within and between grains, and it no longer requires the artificial setting of the grain boundary migration direction. The model is then applied to simulate grain growth under varying stored energy fields and triple junction dragging effect. It was observed that, due to the different directions of local and long-range energy minimization, grain boundaries may migrate in opposing directions sequentially. When compared to a uniform stored energy field, the competition between stored energy minimization and grain boundary free energy minimization is more pronounced in a non-uniform stored energy field, and it is more likely to lead to the combination of triple junctions and the dissociation of quadruple junctions.