通过热轧实验测试、金相观测和有限元分析,研究了轧制温度对AZ31B镁合金铸轧板边裂和组织的影响,以及板坯辐射散热过程中的温度分布。结果表明:实际轧制温度控制在350~400℃时,有较为理想的成材率和晶粒组织;沿板宽方向,板坯中部温度明显高于边部,致使轧制过程中板坯中部纵向延伸大于边部,边部不均匀变形和中部给予边部的纵向附加拉应力是边裂产生的直接原因;边部裂纹附近伴有明显的孪晶组织。 Through the hot rolling test, metallographic observation and finite element analysis, the effect of rolling temperature on the edge cracking and microstructure of the as-cast AZ31B magnesium alloy sheet and the temperature distribution during slab radiation were studied. The results show that when the actual rolling temperature is controlled at 350-400 ℃, the yield and grain structure are ideal. The temperature in the middle of the slab is obviously higher than that in the edge of the slab along the width direction of the slab, The extension of the edge than the edge of the uneven deformation of the edge and the middle of the edge of the longitudinal additional tensile stress is the direct cause of edge cracking; near the edge of the crack accompanied by significant twins.