The effect of process parameters on the hardness and wear resistance performance of laser cladded Ti-Si coatings on Ti-6Al-4V alloy

Laser cladding of silicon powder on Ti-6Al-4V titanium alloy was carried out using an ND:YAG laser. Ti-6Al-4V possesses poor tribological properties along with a hardness value that is on the low side. Therefore, the aim of this study is to improve its wear resistance and also increase hardness in order to prolong the service life. The powder variations utilised were 5%, 10% and 20% Si, with the balance being pure titanium powder. The following process parameters were investigated: Laser power, scanning speed and powder flow rate. Results showed increase in wear rate and microhardness with increasing silicon content. It was also found that a lower laser power (1.2 kW), a medium scanning speed (0.45 m/min) and a higher powder flow rate (6 g/min), resulted in the achievement of the highest hardness. Thus, process parameters are key determinants in microstructural development and material properties for engineering applications.