Influence of VC, Cr₃C₂ on Sintering Properties of Nanocrystalline WC-Co Composite Powders

Nanocrystalline WC-10Co composite powders were sintered by hot-press sintering at 1360℃. The influence of 1.0% VC and 1.0% Cr₃C₂ (mass fraction) growth inhibitors on the sintering properties of the composite powders was investigated according to the transverse rupture strength (TRS), Rockwell A hardness (HRA) and the scanning electron microscopy (SEM) micrographs of the fractured surfaces of specimens. The result shows that the inhibiting grains growth effect of 1.0% VC is better than that of 1.0% Cr₃C₂. When nanocrystalline WC-10Co composite powders doped by 1.0%VC or 1.0% Cr₃C₂ (mass fraction) are sintered at 1360℃, ultrafine WC-10Co cemented carbide with an average grain size of less than 300 nm and better properties are achieved.