Formation mechanism and mechanical properties of TiC reinforced Inconel 718 composite coatings by laser cladding on H13 steel

The poor wear resistance and hardness of H13 steel bring some challenges to its application in complex working conditions, so the TiC particles reinforced Inconel 718 composite coating is produced by laser cladding with different ceramic mass fractions to improve its mechanical properties. A 3D finite element model is established to simulate heat transfer, and the effect of TiC content on the microstructure morphology, evolution mechanism, and mechanical properties of the cladding layer is explored; the results show that the relative intensity of all the diffraction peaks of TiC increases with the increase of TiC content. The microstructure of the cladding layer mainly exists in the forms of granular eutectic TiC, dendritic primary TiC, incompletely dissolved TiC, and γ; both the microhardness of the cladding layer and the penetration zone increase with the increase of TiC content, where the microhardness is higher than that of the substrate. In particular, the 5 wt.% TiC/Inconel 718 coating exhibits the optimal comprehensive performance, with much higher microhardness and wear resistance compared to the substrate and other coatings; and especially the wear volume of the matrix is about 13 times that of the sample when 5 wt.% TiC is added.