Effect of WC content on the microstructure and mechanical properties of (Ti, W)(C, N)-Co cermets

Effect of WC addition on the microstructure and mechanical properties of TiC(sub)-TiN(nm)-WC-Co-C system cermets were studied in this work. The microstructure was investigated by means of X-ray diffractometry (XRD), scanning electron microscope (SEM) in combination with energy dispersive spectrometer (EDS). Mechanical properties such as transverse rupture strength, fracture toughness and hardness were also measured. Results show that the microstructures of cermets exist black core-grey rim structure, white core-grey rim structure and no core-rim structure. The microstructure has a trend to become finer with the increase of WC content. Results also show that the transverse rupture strength and the hardness increase with the increase of WC content, the fracture toughness decreases with increasing WC content, but the change is not obvious when WC addition goes from 10 to 20 wt%. (C) 2007 Elsevier Ltd. All rights reserved.