中文摘要：

在轧制温度350℃和轧制速度0.5 m/s条件下,分别以20%,30%,40%的压下量对铸轧态AZ31B镁合金板进行了轧制实验,对比了轧制后的微观组织,探究在不同压下量下镁合金板边部和中部区域微观组织变化及其产生原因。结合CA（元胞自动机）数学模型对镁合金的动态再结晶过程进行了数值模拟。结果表明：区域应力场变化所引起的空洞聚集是轧制裂纹扩展的主要原因之一;镁合金板中部和边部晶粒尺寸值平均减小幅度为39.6%和55.5%;CA数值模拟结果预测精度较高,平均相对预测误差在16.03%以内。

英文摘要：

Cast-roll AZ31 B magnesium alloy plate was subjected to rolling with reduction of 20%, 30% and 40%respectively at rolling temperature of 350℃ and rolling speed of 0.5 m/s. The microstructures after rolling were contrasted.The microstructure changing and its causes of magnesium plate in edge and central regions were explored. Combined with CA（cellular automata） mathematic model, the dynamic recrystallization process of AZ31 B magnesium alloy was numerically simulated. The results show that： the hole accumulation caused by the variation of regional stress field is one of the main causes of rolling crack extending. The average reduction rates of the grain size of the magnesium plate in the central and edge are 39.6% and 55.5%.The prediction accuracy of CA numerical simulation results is high, and the average relative prediction error is within 16.03%.