Microstructure and properties of IN718/WC-12Co composite coating by laser cladding

To improve microhardness and tribological properties of IN718, WC-12Co particles were added to it by the laser cladding. This study investigated the effect of the content of WC-12Co on the microstructure, phase composition, microhardness, tribological properties and machinability of the composite coating. The results shows that WC12Co can inhibit the growth of columnar grains and the (200) growth direction of gamma-Ni, and refine the microstructure. The average microhardness of coating increases from 245.83HV0.5 to 462.63HV0.5 with the increase of WC-12Co content. The coating containing 30% wt. WC-12Co has the smallest wear loss, that is, the best wear resistance. However, the coating containing 20 wt% WC-12Co has the lowest COF (0.518), that is, the best antifriction capability. With the increase of WC-12Co content, the milling force increases and the instability of the cutting process is aggravated. Moreover, with the addition of WC-12Co, the wear mechanism changed from adhesive wear to abrasive wear and oxidation wear.

Automated summary

The addition of WC-12Co particles through laser cladding can significantly improve the microhardness and tribological properties of IN718. The content of WC-12Co has a significant effect on the microstructure, hardness, and tribological properties of the composite coating.