Improved mechanical performance and wear resistance of Ti-coated cBN–WC–Ni composites

Composites of 0–20 vol% Ti-coated cBN (cBN@Ti) particles dispersed in WC–Ni were densified by spark plasma sintering under 50 MPa at 1300 °C. The cBN particles were distributed homogeneously with a Ti-rich interfacial layer between the cBN particles and WC–Ni matrix. Increasing cBN@Ti to 20 vol% decreased the sample densification, but all the composites were still >97.5% dense. The Vickers hardness and flexural strength initially increased and then decreased, reaching the maximum values of 1820 HV10with 15 vol% cBN@Ti and 1500 MPa with 5 vol% cBN@Ti, respectively, whereas the fracture toughnessKICgradually increased from 8 to 13 MPa m1/2. For cutting rocks, the wear significantly decreased with 5–15 vol% cBN@Ti but increased with 20 vol% cBN@Ti because of cBN particles pull-out.