Oxidation behaviour of Al2O3–TiC–Co composites at 800–1000 °C in air

Abstract The oxidation behaviour of nanometre and micrometre sized Al 2 O 3 –TiC–Co composites is investigated at 800–1000 °C in air for 25 h. The oxidation resistance of nanometre sized samples is better than of micrometre sized. Phase compositions and microstructures were studied by XRD and SEM. The values of general rate constant k and oxidation exponent n are dependent on oxidation temperature and composites. The oxidation kinetics followed a rate that is slightly faster than the parabolic-rate law at 800–1000 °C. The activation energy of the nanometre sized is higher than of micrometre sized in the range of 800–1000 °C.