Effect of element Gd on phase constituent and mechanical property of Mg-5Sn-1Ca alloy

The Mg-5Sn-1Ca-xGd (x=0, 1) alloys were chosen to investigate the change in solidification paths, phase formation and mechanical properties. The microstructure of as-cast Mg-5Sn-1Ca alloy is composed of α-Mg, Mg2Sn and CaMgSn phases. With the addition of Gd, the formation of the Mg2Sn phase is impeded and the CaMgSn phase is refined, whereas the ultimate tensile strength and elongation decrease. The possible reasons for the variation in microstructure and mechanical properties were discussed.