High temperature oxidation behaviour of Ag–36.35 wt.% Zn and Ag–38.50 wt.% Zn–0.60 wt.% Al

Abstract Ag–36.35 wt.% Zn and Ag–38.50 wt.% Zn–0.60 wt.% Al were oxidised in air at 450–650 °C up to 48 h. The oxidation kinetics of both alloys were parabolic with the lower rate constant for the latter alloy. After oxidation for 48 h, thermal oxide scale on Ag–36.35 wt.% Zn was ZnO at all studied temperatures. When 0.60 wt.% Al was added to Ag–38.50 wt.% Zn, ZnO and ZnAl 2 O 4 were formed at all studied temperatures. Al 2 O 3 was evidently observed at 550 and 650 °C. The formation of Al-containing oxides helped reduce the oxidation rate of Ag–38.50 wt.% Zn–0.60 wt.% Al.