5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

Grain growth, a competitive growth of crystal grains that occurs after or simultaneously with solidification, is one of the most important phenomena in controlling the microstructure of polycrystalline materials. The fundamental process underlying grain growth is the migration of grain boundaries; thus, the growth behavior is largely dominated by the properties (energy and mobility) of grain boundaries. In real materials, these properties usually exhibit strong anisotropies depending on the boundary structures. Over the past few decades, many researchers have attempted to elucidate the effects of the anisotropies of the boundary properties on grain growth by performing numerical simulations. However, conclusive knowledge is not yet established especially for three-dimensional systems, mainly due to the limitations in the computational accuracy of the grain growth models and computer resources that have been employed so far. To address the above issues, based on the multi-phase-field (MPF) grain growth model [I. Steinbach and F. Pezzolla, Physica D (1999) 385], this study proposes a novel numerical scheme to accurately handle the anisotropic grain boundary properties. Furthermore, the MPF simulations are drastically accelerated by parallelizing multiple graphics processing units (GPUs) on a GPU-rich supercomputer. Using these techniques, we perform a series of large-scale simulations on anisotropic grain growth, through which the effects of the anisotropic grain boundary properties on the growth behaviors are elucidated in detail.