The oxidation behavior of the WC-10Â wt.% Ni3Al composite fabricated by spark plasma sintering

The oxidation behavior of the novel WC-Ni3Al composite prepared by spark plasma sintering is investigated. The results indicate that the oxidation resistance of the WC-10 wt.% Ni3Al composite is more excellent than that of the WC-8 wt.% Co composite at high temperature. It probably results from the formation of compact oxide layers and the oxidation products: NiWO4 and Al2(WO4)3, which possess lower porosity and consequently provide more efficient passivation effect against oxidation. The activation energies produce a difference between the WC-10 wt.% Ni3Al (169 ± 1 kJ/mol) and WC-8 wt.% Co (190 ± 3 kJ/mol) at 600-800 °C. Cyclic oxidation experiments reveal that the adhesion of the oxide film for the WC-Ni3Al composite is better than the WC-Co composite which has a positive effect on improving oxidation resistance at high temperature.