Effect of Y on high-temperature oxidation behavior and products of AZ80 alloy

Oxidation resistance and products of the AZ80 alloys with (0, 0.32, 1.07 wt %) Y were investigated via isothermal oxidation test at temperatures between 413 °C and 445 °C. The results revealed that alloys showed linear or power law kinetics weight gain with time at each temperature. The alloying element Y facilitated the reaction of MgO + CO2MgCO3 in the outer oxide layer of AZ80, which changed flocculent shape oxides (MgO) to granular oxides (MgCO3). Oxide layer with flocculent shape oxides is loose, while that with granular oxides is compact and can prevent alloy matrix from further oxidation. A further insight into oxidation mechanism of magnesium alloys is obtained.