Friction and dry sliding wear behaviour of cermets

It is shown that wear resistance and coefficient of friction depend on the type and chemical composition of the cermets. The WC-Co cermets have the highest wear resistance. The wear rate of WC-Co and TiC-NiMo cermets increased with increasing binder content in the cermets. The wear of Cr3C2-Ni cermets is more complicated and depends on the composition of cermets. The wear of WC-Co cermets is caused mainly by preferential removal of the cobalt binder, followed by fracture of the intergranular boundaries and fragmentation of the carbide grains. The main wear mechanism in the TiC-NiMo cermets is polishing (micro-abrasion) and adhesion, resulting in a low wear rate. The main wear mechanism of Cr3C2-Ni cermets involves thermal cracking and fatigue-related crushing of large carbide grains and carbide framework and also adhesion.