Effect of ceramic reinforcement on the slurry abrasion behaviour of high-velocity oxy-fuel sprayed WC-12Co coating

High-velocity oxy-fuel (HVOF) sprayed WC-12Co coatings are extensively employed to protect engineering components operating under severe abrasive environments; however, improving their resistance to slurry abrasion remains a significant challenge. In the present study, WC-12Co and CrB 2 + TiC reinforced WC-12Co composite coatings were deposited on SS304 stainless steel substrates using the HVOF process to evaluate the influence of ceramic reinforcements on their microstructure, mechanical properties, and slurry abrasion performance. The deposited coatings were characterised using field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy, X-ray diffraction, nanoindentation, surface roughness, and porosity measurements. Both coatings exhibited dense microstructures with continuous coating/substrate interfaces and retained WC as the dominant phase after deposition. The reinforced coating demonstrated higher hardness, elastic modulus, and lower porosity than the WC-12Co coating. Slurry abrasion tests revealed the lowest mass loss for the reinforced coating under all operating conditions, whereas the uncoated SS304 substrate exhibited the highest wear. Post-abrasion FESEM analysis confirmed reduced particle detachment and localised abrasion in the reinforced coating, while severe ploughing and abrasive cutting dominated the wear of SS304.