Effect of WC addition on the microstructure and mechanical properties of TiN-based cermets

The TiN-WC-Ni-Co system cermets with nearly full density were successfully fabricated by conventional vacuum sintering with the addition of WC. Effect of WC addition on the microstructure and mechanical properties of TiN-based cermets was studied in this work. The results showed that WC helped to improve the wettability significantly between TiN and Ni/Co through the formation of typical core-rim structure, which is rather beneficial to obtain the cermets with full densification and homogeneous microstructure. As the addition of WC content increased from 0 wt% to 25 wt%, the microstructure had a marked trend to become denser and finer and the mechanical properties of the TiN-based cermets were enhanced greatly. When the WC content was 20 wt%, the relative density, transverse rupture strength, fracture toughness and Rockwell hardness of the cermets reached 99.5%, 1235 MPa, 12.6 MPa m1/2 and 88.2, respectively.