Microstructure evolution, recrystallization and tribological behavior of TiC/WC composite ceramics coating

Abstract

TiC/WC composite ceramics reinforced Ni-based coating was manufactured on the mild steel via PTA technology. Different WC/TiC mass ratio schemes were designed and the total amount of MC ceramics was kept 40 wt%. Recrystallization of TiC could provide a unique source of trace element (Ti) that refined the microstructure of the original WC/Ni-based coating. With the addition of TiC, coarse dendritic in the WC/Ni-based coating evolved into uniformly dispersed blocky microstructure. The edge of the unmelted TiC particles formed a reaction layer, which enhances the binding force of TiC/matrix. In addition, TiC inhibits the formation of M23C6, and W element was solidly soluble in the recrystallized TiC. In the four groups of experiments, by microhardness test, it can be found that replacing the same WC content with TiC has a significant effect on the average microhardness. Compared with 40 wt% WC reinforced Ni-based coating, both the coefficient of friction and the volume loss of the coating were reduced with the addition of TiC by dry sliding wear test.