In-situ fabrication TiB2 2 reinforced TiCN-based cermets from TiCN-B4C-Ti-Co 4 C-Ti-Co system by spark plasma sintering

TiB2-reinforced 2-reinforced TiCN-based cermets were successfully fabricated by spark plasma sintering (SPS) from a TiCN-TiB4C-Co 4 C-Co system. The effects of Ti/B4C 4 C composite powders (TBCs) addition on the sintering behavior, microstructure, mechanical properties, and wear resistance were investigated. The results indicated that all the cermets with different TBCs contents were composed of TiCN, TiB2, 2 , and Co without other impurities. Moderate addition of TBCs could effectively promote densification and refine TiCN grain. The Vickers hardness and fracture toughness simultaneously increased with TBCs addition. The cermet with 30 wt% TBCs addition possessed excellent mechanical properties (Vickers hardness of 1725 HV and fracture toughness of 7.1 MPa m 1/ 2 ). The strengthening and toughening mechanisms were investigated in detail. The wear resistance property was significantly enhanced by the in-situ incorporation of TiB2 2 owing to the improved hardness and grain refinement.