Effects of Bi and Ce addition on tensile properties and corrosion resistance of Zn-15Al alloys by continuous casting and extrusion

Abstract

The effect of Bi or Ce as alloy elements were added into the Zn-15Al alloys by continuous casting and extrusion (CASTEX) to improve the tensile properties and corrosion resistance was investigated. The results indicated that the addition of Bi or Ce to CASTEX Zn-15Al alloys could not form new phase. The distribution of Bi was homogeneous in the alloys, but the Ce focused on the Zn-rich η phase. The refinement effect of Ce was better than that of Bi for CASTEX Zn-15Al alloys. The result of tensile test indicated that the CASTEX Zn-15Al alloys by adding Ce element led to higher ultimate tensile strength and ductility. Corrosion behavior of CASTEX Zn-15Al-0.2Bi and Zn-15Al-0.2Ce alloys was investigated in 3.5 wt% NaCl solution using electrochemical measurements. The results show that CASTEX Zn-15Al-0.2Ce alloys have higher corrosion resistance.