Phase-field model for anisotropic grain growth

Grain boundary properties may depend on the five macroscopic crystallographic degrees of freedom of the boundary, these being the misorientation between crystals and the inclination of the boundary plane. An orientation-field model is developed which uses a single-well potential and allows the grain boundary energy and mobility to depend on all five macroscopic degrees of freedom. The model reproduces the analytical equilibrium dihedral angles at triple junctions, has no anomalous trijunction drag, and Wulff shapes for cubic grain boundary energy anisotropy. Polycrystalline simulations in two dimensions demonstrate a pronounced effect of low angle grain boundaries on the microstructure evolution, demonstrating the importance of accounting for misorientation-dependent energy, particularly in highly textured materials. This model serves as a simple, computationally efficient, and physics-based method for simulating grain growth phenomena. With the ability to tune the grain boundary energy and mobility, the model shows promise for use in large scale simulations of grain coarsening in a wide range of systems.