The effect of addition of metallic carbides Cr3C2 and Cr3C2 + VC on structure and mechanical properties of WC-10wt%Co nanocomposites have been studied. After preparing and compacting of the powders under pressure of 200 MPa, the samples were sintered at temperatures of 1370°C, 1410°C and 1450°C for 1 hour. Microstructural examinations by SEM show that the average grain size obtained for Cr3C2 + VC added alloys reduced 50 percent and also grain size distribution was narrower compared to those samples without grain growth inhibitors. Furthermore, co-addition of Cr3C2 and VC rise to a higher Vickers hardness and fracture toughness of the sintered alloys at 1410°C.
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