微钙合金化和电磁场对AZ31镁合金复合作用的研究

Effects of Microalloying of Ca and Electromagnetic Field on the AZ31 Magnesium Alloy

摘要:

对变形AZ31镁合金在连铸过程中有、无施加电磁场和微钙合金化进行试验研究，并对铸锭的表观质量、微观组织和力学性能进行对比分析。结果表明：微钙合金化和电磁场复合作用能连续铸造出表面光滑、无氧化夹杂和偏析瘤的高质量铸锭，合金的微观组织得到改善，合金的晶粒在铸锭内外一致，析出相呈圆点状或近圆点状弥散分布于基体。微钙合金化和电磁场复合作用对合金抗拉强度的提高近15%，对合金延伸率的改善更加有效，相对于普通连铸的AZ31镁合金，在微钙合金化和电磁场复合作用下AZ31镁合金的延伸率提高近90%

Abstract:

The continuous castings of wrought magnesium alloy AZ31 with or without the effects of electromagnetic field and Ca microalloying were investigated，and the appearances, microstructures and mechanical properties were compared. The results show that the ingots with the electromagnetic field casting (EMC) and Ca microalloying have smooth surface, and the defects, such as segregation, trapped oxide can be eliminated on the ingot surface. Through EMC and Ca microalloying, the microstructure is improved and the grain in the border and center of the ingot has a same size, the β-Mg17Al12 phases with the shape of dot and approximate dot distribute in the basal body uniformly. The yield strength and elongation increase by 15% and 90%, respectively, for the ingot with EMC and Ca microalloying compared to the ingot without EMC and Ca microalloying