Microstructure, tensile properties and compressive creep resistance of Mg-(5-8.5)%Sn-2%La alloys

The microstructure, tensile properties and compressive creep resistance of permanent-mould cast Mg-(5-8.5)%Sn-2%La (mass fraction) alloys were investigated. The results show that Mg-(5-8.5)%Sn-2%La alloys are all composed of alpha-Mg phase, Mg2Sn and Mg-La-Sn compounds. Compared with those of Mg-5%Sn binary alloy, the grain size and the content Of Mg2Sn compound in Mg-5%Sn-2%La alloy are decreased. With the increase of Sn content in Mg-(5-8.5)%Sn-2%La alloys, the content of Mg2Sn compound increases, while that of Mg-Sn-La compound changes little. In addition, the investigation suggests that the thermally stable Mg-Sn-La and Mg2Sn compounds can improve the tensile properties and compressive creep resistance of the alloys.