The corrosion behaviour of a novel Mg–Zn–Zr–Y–Cu alloy

Abstract

A novel Mg–Zn–Zr–Y–Cu alloy was fabricated, and its corrosion behaviour was investigated in the present work. The results showed that, compared with Mg–6Zn–0.5Zr (ZK60) alloy, Mg–6Zn–1Y–0.5Cu–0.5Zr (ZWCK6100) alloy exhibited finer recrystallised (DRXed) and unDRXed grains, more homogeneous microstructure, and contained CuMgZn and I phase (Mg3Zn6Y) in addition to α-Mg, Zn2Zr, MgZn2 precipitates. As a result, ZWCK6100 alloy had a lower corrosion rate and higher corrosion resistance, underwent slightly localised corrosion in 3.5 wt-% NaCl solution, implying that the combined addition of Y and Cu was conducive to improving the corrosion resistance of Mg alloys.