Mg-2.5Zn-1.0Ca-xSn合金的微观组织与力学性能

Microstructure and Mechanical Properties of Mg-2.5Zn-1.0Ca-xSn Alloys

摘要: 采用OM、SEM、XRD分析、硬度测试和拉伸试验等手段，研究了铸态Mg-2.5Zn-1.0Ca-xSn（x=0.1～2.0）合金的微观组织与力学性能。结果表明：Mg-2.5Zn-1.0Ca-xSn合金组织主要由α-Mg、Mg₂Ca、Ca₂Mg₆Zn₃和Mg₂Sn相组成。随着Sn含量的增加，合金的平均晶粒尺寸逐渐减小，晶界处的Mg₂Sn相数量逐渐增加，尺寸不断增大。随着Sn含量的增加，合金的硬度逐渐升高，抗拉强度和伸长率先升高后降低，Mg-2.5Zn-1.0Ca-1.0Sn合金的抗拉强度和伸长率均达到最高，分别为145.3 MPa和4.6%。

Abstract: The microstructure and mechanical properties of as-cast Mg-2.5Zn-1.0Ca-xSn（x=0.1-2.0） alloy were studied by OM,SEM,XRD,hardness test and tensile test.The results show that the microstructure of Mg-2.5Zn-1.0Ca-xSn alloy is mainly composed of α-Mg,Mg₂Ca,Ca₂Mg₆Zn₃and Mg₂Sn phases.With the increase of Sn content,the average grain size of the alloy decreases gradually,the amount of Mg₂Sn phase at the grain boundary increases gradually,and the size increases continuously.With the increase of Sn content,the hardness of the alloy increases gradually,and the tensile strength and elongation of the alloy increase first and then decrease.The tensile strength and elongation of Mg-2.5Zn-1.0Ca-1.0Sn alloy are highest,which are 145.3 MPa and 4.6%,respectively.