Effect of Ni on the Microstructure and Diffusion Behavior at the Interface of WC/High-Speed Steel Composites

In this study, WC-Ni/high-speed steel composite materials for application as micro-drills were prepared by cold pressing and high-temperature vacuum sintering using a self-designed mold in the laboratory. The effect of Ni on the microstructure and diffusion behavior at the interface of the WC/high-speed steel composite was investigated. The results show that the addition of Ni promoted the diffusion of elements, and reduced defects such as micropores and microcracks at the WC/high-speed steel composite interface. It also improved the bonding strength of the WC/high-speed steel composite interface, and significantly decreased the WC hardness.