The oxidation behavior of Al2O3-based composites with a 5 vol% Ni particle dispersion was investigated at high temperatures in air. The oxidized layer consisted of Al2O3 and NiAl2O4. The growth of the oxidized layer followed a parabolic manner, which means that mass transport in the oxidized layer was the rate-controlling process. The value of the parabolic rate constant at 1300°C was 1.8×10-14 m2s-1 which is higher than those of SiC-dispersed Al2O3 composites and Al2O3-former alloys.
Keywords: high temperature oxidation, nickel, alumina, NiAl2O4, composites