元胞自动机模拟形变组织的网格映射模型

Grid mapping model of deformed microstructure in cellular automaton

文章采用正六边形网格划分法、最近邻邻居关系以及周期性边界条件的元胞自动机方法,获得等轴的母相微观组织。在此基础上建立网格映射模型,模拟得到静态再结晶前的形变组织以及动态再结晶过程中的形变组织,并与实验结果进行对比。结果表明,模型计算得到的尺寸误差较小,能够满足尺寸精度的要求。模拟得到微观组织随着应变的增加,晶粒形态沿变形方向伸长。应变越大,晶粒伸长的程度也越大。在大的应变量下,等轴的微观结构演变成纤维组织。模拟结果与实验结果符合较好,表明本模型能够用于模拟材料的形变组织。

Based on the cellular automaton （CA） made up of regular hexagon cells, the nearest neighbor type and periodic boundary condition, equiaxial microstructure as parent phase was obtained. Grid mapping model was constructed in this foundation. Deformed microstructures before static recrystallization and during dynamic recrystallization were simulated, and then compared them with experiments. It turned out that dimension error calculated by grid mapping model is smaller than required precision. Simulated grain shape elongated in the deformation direction. The larger the true strain ε, the more grain shape extended. Equiaxial microstructure evolved into fibrous structure at large strain. Simulated microstructure and experiments agreed pretty well, which showed that the grid mapping model can be used to simulate deformed microstructure.