LAUSR

ABSTRACT The Ti–SiC–ZrB2 cermet coatings were fabricated on Ti6Al4 V by laser cladding with a 4 kW continuous wave Rofin Sinar Nd:YAG laser system. Three compositions of the cermet coatings of varying percentages of ZrB2 (0 wt-%, 5 wt-% and 10 wt-%) were added. Scanning electron microscopy and energy dispersive spectroscopy were used to study the microstructure of the coatings while X-ray diffractometry was utilised to investigate the existing phases on the coatings. The microstructures of the coatings were majorly characterised by secondary precipitates of granular TiC and Ti5Si3 in β-Ti matrix. With the addition of ZrB2, new phases developed which were dispersed. This resulted in a corresponding increase in surface hardness where the resultant hardness values of the laser clad coatings were found to be approximately four times higher than Ti6Al4 V alloy.