Phase field crystal study of grain boundary structure and annihilation mechanism in low-angle grain boundary

Using the advantage of phase field crystal model in microstructure evolution, we simulated the details of two-dimensional triangular phase on atomic scale and diffusion time scale. The results show that the annihilation process of grain boundaries can be divided into three stages. The energy changes of the system at different stages are accurately calculated and the process is quantitatively analyzed. By comparing the atomic density distributions at different temperatures and orientation angles, it is shown that the grain boundary is sensitive to temperature. Within the range of low-angle, the increase of orientation angle inhibits the occurrence of annihilation and decreases the grain boundary migration rate. Under the applied stress, the orientation angle has a certain response relationship with the yield strength of the material. This work has some practical significance in the influence of microstructure on the mechanical properties of materials.