WC–α-Al2O3 composites, with the rare earth oxides (Y2O3 or CeO2) as sintering additives, were fabricated by mechanical alloying and hot pressing sintering. The microstructure and mechanical properties of WC–Al2O3 with and without oxides were investigated. The appearance of rare oxides increased the density of sintered bulk materials and suppressed the decarburisation due to the decrease of surface activation energy in sintering process. The hardness and fracture toughness of the samples first increased and then decreased, indicating that an appropriate addition of Y2O3 or CeO2 could strengthen the properties of samples. Microstructure observation results revealed that the grain growth of WC was significantly retarded, and the homogeneity of Al2O3 particulate dispersion was improved with the addition of Y2O3 and CeO2.
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