Effect of Laser Power on Hardness and Wear Rate of Additive Manufactured Hybrid TI6AL4V Metal Matrix Composites

Abstract

Additive manufactured hybrid Ti6Al4V composites are an interesting research area with potentials to advance structural applications of Ti6Al4V in aeronautical engineering, for instance in turbine engine components. Experimental research has demonstrated that adding wear resistance particles during additive manufacturing is a sure way of improving the mechanical properties of Ti6Al4V alloy for better applications where surface coatings are carried out. This paper investigates the effect of laser power on hybrid Ti6Al4V metal matrix composites (MMCs). Microstructure, hardness and wear rate analyses were carried out and meticulously reported. 3 kW Nd: YAG laser power was used for coatings which involved the combination of particles of Ti6Al4V, B4C and BN on Ti6Al4V alloy substrate at laser power variation of 1400 W and 2000 W, respectively. Results of microstructure showed well distributed BN - B4C particle free from cracks and pores thus contributing to an excellent overall result. 50% overlapping multiple coating tracks were cut to specification for the microhardness test and the wear test was carried out using the dry sliding technique, under dry sliding conditions of 2 mm stroke length at room temperature with a WC ball counterbody. The response of the effect of laser power on the hardness and wear of the manufactured part was reported as observed by SEM and X-ray diffraction spectroscopy.