Corrosion properties and microstructure of a broad range of ce additions on Mgzn alloy

Abstract

To launch a new class of Mg alloys based on the MgZn system, the effect of microstructural evolution on the corrosion properties in MgCeZn system has been investigated. The alloys were fabricated by using a vacuum induction melting method under an argon atmosphere. Potentiodynamic polarization and hydrogen evolution test were carried out in 3.5% NaCl solution of pH 7.2 at room temperature to evaluate the corrosion properties of MgCeZn alloys. The main constituents in M g99Ce 0.5Zn 0.5, M g98Ce 1.5Zn 0.5 and M g92Ce 7.5Zn 0.5 alloys are α-Mg and M g12Ce phase. On the other hand, M g41Ce 5 and Mg3Ce phases are present in M g88Ce 11.5Zn 0.5 and M g86Ce 13.5Zn 0.5. Although Ce additions on Mg alloy could tend to ennoble the corrosion potential, the corrosion rate was increased with excessive Ce additions. © 2012 Japan Foundry Engineering Society.