基于元胞自动机AZ31镁合金微观组织模型

以AZ31镁合金在热压缩过程中微观组织演变为基础,结合元胞自动机模型(CA),建立了镁合金变形过程中再结晶晶粒尺寸模型和动态再结晶百分数模型。通过对铸态AZ31镁合金在不同变形条件下的热压缩实验,推导出镁合金的位错密度模型、临界位错密度模型、形核率模型和晶粒长大模型。结合元胞自动机具体演变规则,建立元胞自动机模型,并利用应力应变曲线及晶粒大小验证元胞自动机的模拟结果,验证该模型的准确性,结合实验数据和JMAK理论,推导出再结晶晶粒尺寸模型和动态再结晶百分数模型。借助DEFORM-3D分析软件得到镁合金在变形过程中,晶粒尺寸分布的变化情况以及动态再结晶百分数分布的变化情况。

Microstructure Model of AZ31 Magnesium Alloy Based on Cellular Automaton

Based on the microstructure evolution of AZ31 magnesium alloy during hot compression, a recrystallization grain size model and dynamic recrystallization percentage model were established by the cellular automaton model. The dislocation density model, critical dislocation density model, nucleation rate model and grain growth model of magnesium alloy AZ31 were deduced by thermal compression experiments under different deformation conditions. Combining the specific evolution rules of cellular automata, cellular automata model was established. The simulation results and accury of cellular automata were verified by stress-strain curves and grain size. Based on the experimental data and the JMAK theory, the recrystallization grain size model and dynamic recrystallization percentage model were deduced. With DEFORM-3D analysis software, the change of grain size distribution and dynamic recrystallization percentage distribution in deformation were obtained.