The microstructure, mechanical properties and corrosion behaviour of Ce-containing Mg-3Sn-1Ca alloy

Abstract

The effects of minor Ce on the microstructure, mechanical properties and corrosion behaviour of Mg-3Sn-1Ca alloy are investigated systematically. The minor Ce can refine the eutectic structure between α-Mg and CaMgSn and make the microstructure more uniform. The maximum ultimate tensile strength and elongation of the alloy with the Ce content of 0.3 wt-% were 152.5 MPa and 4.1%, respectively. Meanwhile, the corrosion resistance of the Ce-containing alloys is improved by Tafel curves and electrochemical impedance spectra, especially when the Ce is up to 0.3 wt-%. The minor Ce can promote the formation of the surface film and makes the corrosion product film to become more compact, which effectively prevents further the occurrence of corrosion of the Mg matrix.