(大连理工大学 材料科学与工程学院，辽宁 116024)
摘 要: 以Mg-8%Li-3%Al合金为基体，研究合金化元素Ca以及Ca与电磁搅拌复合作用对其凝固组织和力学性能的影响，并探讨其化学成分、组织结构和力学性能间的关系。结果表明：合金化元素Ca以及Ca与电磁搅拌复合作用都能改善Mg-8%Li-3%Al合金的凝固组织和力学性能；当铸态合金中Ca含量为0.5%(质量分数)时，合金中β相细小均匀，室温抗拉强度和伸长率分别达到188.93MPa和11.35%；施加80 V电磁场电压以及加入0.5%Ca后，晶粒组织均匀有序，布氏硬度、抗拉强度和伸长率分别为67.5HB、203.8MPa和7.7%。
关键字: Mg-Li-Al合金；电磁搅拌；凝固组织；力学性能
microstructures and mechanical properties of Mg-Li-Al alloys
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Abstract:The effects of Ca and combined electromagnetic stirring and Ca on the microstructures and mechanical properties of Mg-8%Li-3%Al alloys were studied, and the relationships among the chemical composition, microstructures and mechanical properties were discussed. The results show that both Ca and combined electromagnetic stirring and Ca improve the microstructures and mechanical properties of Mg-8%Li-3%Al alloys. Adding 0.5% Ca into the as-cast alloys, the β phase becomes thinner, and the tensile strength and elongation reach to 188.93 MPa and 11.35%, respectively. The microstructure is fine and uniform, and the Brinell hardness, tensile strength, and elongation are 67.5HB, 203.8 MPa and 7.7% at electromagnetic stirring of 80 V combined with 0.5%Ca.
Key words: Mg-Li-Al alloy; electromagnetic stirring; microstructure; mechanical properties
