Exploration of microstructure and wear behaviours of laser metal deposited Ti6Al4V/Cu composites

Abstract: This paper reports on the investigations conducted on the evolving microstructures and the dry sliding wear of the laser deposited Ti6Al4V/Cu composites. Some selected process parameters were used for the experiments. The laser powers were chosen between 1300 W and 1600 W; scanning speeds were selected between 0.30 m/min and 0.72 m/min while other parameters are as specified in the experimental matrix. It was found that all the composites produced showed good and high-quality microstructures and they exhibited very low or no fusion zones which were as a result of the selected process parameters used. The α-phase region of the composites was found to be harder than the β-phase region. During the composites cooling, the β-phase field transformed to the basal planes of the hexagonal α-phase thereby creating a lower diffusion coefficient of the α-phase as compared to the β-phase counterpart. The Ti6Al4V/Cu composite produced at a laser power of 1397 W and a scanning speed of 0.3 m/min was found to show the lowest percentage of wear volume and coefficient of friction; and happened due to the martensitic structure formed during cooling. Results obtained showed that the poor abrasive wear of titanium alloy has been improved with the addition of copper into their lattices