The Effect of Er Addition on the Air-Oxidation of a Zr55Cu30Al10Ni5-Based Bulk Metallic Glass

Abstract

Air oxidation behavior of a (Zr55Cu30Al10Ni5)98Er2 bulk metallic glass was studied at 350–450 °C. The results showed that the oxidation kinetics of the alloy followed a multi-stage parabolic rate law, and the parabolic rate constants at the steady-state stage increased with temperature. The oxidation rates of the alloy were higher than those of the Zr55Cu30Al10Ni5 glassy alloy, indicative of poor oxidation resistance for the Er-containing alloy. The scales formed on the (Zr55Cu30Al10Ni5)98Er2 alloy consisted mostly of tetragonal ZrO2 and minor monoclinic ZrO2 and CuO at 350 °C, while Cu2O and Er2O3 were present at T > 400 °C.