Effect of nano-Cr₃C₂ on wear resistance of copper based diamond composites fabricated by vacuum hot pressing

To solve the problem of excessive wear and failure in impregnated diamond bits due to drilling in high-temperature and hard formations, the nano-reinforced copper composites with and without diamond were prepared by vacuum hot pressing-sintering process, with 0 wt%, 1 wt%, 2 wt%, and 3 wt% of nano-Cr₃C₂ being added to the composites. In this paper nano-Cr₃C₂ reinforced diamond composites properties and wear behavior, and the relative densities, bending strengths, hardness and wear ratio of the composites were tested, and the surface, fracture and wear surfaces of the composites were characterized. Adding 2 wt% nano-Cr₃C₂ increased the composite's relative density, the friction coefficient decreased significantly compared to non-reinforced composites. The bending strength of the composite without diamond was increased by 18.5 %, the hardness was increased by 7.5 %, and the wear ratio was increased, because nano-Cr₃C₂ played the role of dispersion reinforcement. As the wear resistance and the holding power of diamond in the composite with diamond were significantly improved, the bending strength increased by 42.2 %, and the wear ratio increased by 45 %.