Sn对AZ890镁合金铸态组织和力学性能的影响

Effects of Sn on the Microstructure and Mechanical properties of as-cast AZ80 alloys

摘要:

通过OM、XRD、SEM和力学性能测试等手段研究了Sn元素对AZ80镁合金铸态组织和力学性能的影响。AZ80-xSn（x=1,3,5wt.%）铸态显微组织呈现出典型的等轴树枝晶形貌，主要有α-Mg，离异共晶Mg17Al12，层片状Mg17Al12，离异共晶Mg2Sn相组成。添加Sn元素可以有效的抑制层片状Mg17Al12相的析出，当Sn添加量为5wt%时，层片状Mg17Al12基本消失。Sn元素添加量少于3wt.%时，具有很好晶粒细化效果。而且，Sn元素具有明显的强化效果，当Sn添加3wt.%时，具有较好的综合力学性能。

Abstract:

The effects of Sn addition on the microstructure and tensile properties of as-cast AZ80 alloy were investigated by the means of OM, XRD, SEM and tensile property test. The microstructure of as-cast AZ80-xSn (x=1, 3, 5, wt.% ) alloys appears typical equiaxed dendrites morphology, which consists of a-Mg primary, divorced eutectic (Mg+Mg₁₇Al₁₂), laminar Mg₁₇Al₁₂, divorced eutectic Mg₂Sn. The addition of Sn elecment effectively suppressed the laminar Mg₁₇Al₁₂ phase precipitating duringSsolidification. When the Sn content was 5 wt.%, the laminar Mg₁₇Al₁₂ phase nearly disappeared. The grain size reduced when the Sn content less than 3 wt.%. Moreover, The alloy was strengthened significantly by Sn content and the AZ80-3Sn alloy had the superior mechanical property.