Effects of Cu on properties of vitrified bond and vitrified CBN composites

•Cu is stable under the protection of argon atmosphere during the sintering process.•The thermal conductivity of the vitrified CBN composites incorporating 8 wt% Cu is up to 8.46 W/m∙K, increasing by 87.6%.•The bending strength of the vitrified CBN composites incorporating 6 wt% Cu reaches the peak value of 71.88 MPa.•The property improvements are due to the formation of thermal conductive paths and toughening mechanism in the composites.

In order to obtain vitrified CBN composites, which have high performance of both thermal conductivity and mechanical strength, the effects of Cu on the properties of vitrified bond and the vitrified CBN composites were comprehensively investigated in this work. The results show that the vitrified CBN composites incorporating 6 wt.% Cu display excellent comprehensive performance including the increases by about 62.1% in thermal conductivity and 16.1% in bending strength. The substantial performance improvement of the vitrified bond and the vitrified CBN composites may be attributed to the high thermal conductivity and good ductility of metal Cu and its toughening effect on the vitrified bond, as well as formation of thermal conductive path in the vitrified bond.