Effect of Ni contents on the microstructure and mechanical properties of TiC–Ni cermets obtained by direct laser fabrication

Abstract TiC–Ni cermets have been produced using direct laser fabrication on a low carbon steel substrate, with 20, 30 and 40 vol.% Ni, respectively. The effects of Ni content on the microstructure and mechanical properties of TiC–Ni cermets were investigated. The TiC particles were produced by an in-situ reaction of titanium and graphite during the direct laser fabrication, instead of being directly injected into the laser molten pool. The results showed that in the cermets only TiC and Ni were present as phases, indicating that TiC was synthesised by the in-situ reaction of Ti and C in the powder mixture and the amount of Ni content did not influence the presence of phases in the final products. Moreover, the results revealed that the increase of Ni content will result in the decrease of bending strength and micro-hardness.