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基于晶界迁移的热激活原子跃迁理论和曲率驱动机制建立了正常晶粒长大的随机型元胞自动机模型。模型定量追踪了元胞空间中每个离散晶界段上的曲率、晶界能和晶界迁移率,计算该晶界段的局部迁移速率并转化为元胞状态转换概率,考察了晶界能和晶界迁移率各向同性及各向异性条件下晶粒生长的拓扑演变和动力学特性。以热挤压态纯镁等温退火为例验证了模型的有效性。结果表明,所建立的元胞自动机模型能够反映晶粒长大过程中晶界能下降的总体趋势,与晶界能和晶界迁移率各向同性的理想条件相比,各向异性条件下晶粒长大指数和拓扑特征与试验结果更为接近。
Based on the heat activated atomic transition theory and the curvature-driven mechanism of grain boundary migration, a random cellular automaton model with normal grain growth was established. The model quantitatively traced the curvature, the grain boundary energy and the grain boundary mobility on each discrete grain boundary in the cell space. The local migration rate of the grain boundary was calculated and transformed into the state transition probability. The effects of grain boundary energy And the topological evolution and dynamics of grain growth under isotropic and anisotropic grain boundary mobility conditions. An example of isothermal annealing of hot-pressed pure magnesium was used to verify the effectiveness of the model. The results show that the established cellular automata models can reflect the overall trend of grain boundary energy decline during grain growth. Compared with the ideal conditions that grain boundary energy and grain boundary mobility are isotropic, under the anisotropic condition The grain growth index and topological features are closer to the experimental results.