电磁连铸对AZ31镁合金组织及力学性能的影响

通过电磁连铸和普通连铸方法对AZ31镁合金进行连铸实验,对比分析有、无电磁场作用下的铸坯凝固宏观、微观组织和力学性能,并利用扫描电镜分析镁合金的断裂机理。结果表明:当表观直流电流为40~50 A时获得最佳磁场分布,此时电磁连铸的镁合金组织细小、均匀,树枝晶呈破碎状,其力学性能尤其是塑性变形能力显著提高,常温抗拉强度、屈服强度和伸长率较普通连铸分别提高17%,50%和81%,断口形貌显示其断裂具有韧性断裂的特性。

Effect of electromagnetically continuous casting on structure and mechanical properties of magnesium alloy AZ31

A test of electromagnetically continuous casting(EMC) was used to cast AZ31 alloy to study the effect of electromagnetic field on the billets,in which the solidification structure and mechanical properties of the billets cast with or without electromagnetic field were examined.The result shows that the optimum distribution of magnetic induction intensity is obtained at the apparent direct current of 40?50 A,and the grain size obtained by EMC is fine and uniform,the dendritic crystal are fragmentated.The mechanical properties of the billet casted by EMC are improved obviously compared with those casted by the traditional casting,and the tensile strength,yield strength and elongation are increased by about 17%,50% and 81%,respectively.AZ31 magnesium alloy casted by EMC usually shows flexible fracture.