The Effect of Ce Addition on Corrosion Behavior of Permanent Mold Casting Mg-4Al-2Sn-1Ca alloy

Abstract

In the present work, the effect of adding Ce on the corrosion behavior of Mg-4Al-2Sn-1Ca alloy was investigated. The studied alloys were fabricated by gravity casting method and a potentiodynamic polarization, A.C. impedance and hydrogen evolution tests were carried out in a 3.5% NaCl solution with pH 7.2 at room temperature to measure the corrosion properties of Mg-4Al-2Sn-1CaxCe alloys. The microstructure of the Mg-4Al-2Sn-1Ca alloy was composed of α-Mg, Mg17Al12, Mg2Sn and CaMgSn phase. Also, a Al11Ce3 phase was newly formed by the addition of Ce. With an increase of the Ce contents, the microstructure became refined and the corrosion resistance improved.