On the enhanced wear resistance of ultra-coarse WC-Co cemented carbides by WCoB addition

Abstract The effect of the WCoB addition on the wear resistance of the ultra-coarse WC-8Co cemented carbides was studied by experiments and finite element simulations. The results showed that with the increase of the WCoB content, the wear resistance of the ultra-coarse cemented carbides was greatly improved. The cemented carbide containing 1.0 wt.% WCoB had a friction coefficient of 0.281 and a wear rate of 0.77×10-6 mm3/N·m, which was 72% and 46% of those of the WC-8Co counterpart. The reason of the significant reduction of the friction coefficient and wear rate was analyzed. WCoB with high hardness distributed homogeneously at WC/WC and WC/Co interfaces, which led to relatively homogeneous distribution of the stress in WC grains and supported the WC grains after Co removal. Consequently, the probability of brittle fracture and pull-out of the WC grains during wear process of the cemented carbides was decreased.