Enhancing corrosion resistance of Mg-Li-Zn-Y-Mn alloy containing long period stacking ordered (LPSO) structure through homogenization treatment

Abstract

This work reported the transformation of (Mg, Zn)24Y5 phase into a long period stacking ordered (LPSO) structure and the reduction of constituent fluctuations induced by massive slender precipitates in α-Mg grains of an as-cast Mg-4Li-4Y–2Zn-0.1Mn (in wt. %) alloy through a simple homogenization treatment. After the treatment, the corrosion resistance of as-homogenized sample significantly improved, primarily attributed to reduced potential differences between LPSO and α-Mg and diminished potential fluctuations in α-Mg compared to the counterparts in the as-cast sample. The corrosion mechanism in both samples was primarily driven by the micro-galvanic effect between (Mg, Zn)24Y5 or LPSO and α-Mg.