Plasma and HVOF sprayed WC–Co coatings as hard chrome replacement solution

In the present study, WC–12Co coating has been deposited using plasma spray and high velocity oxyfuel spraying (HVOF) and wear performances of these coatings have been compared with electroplated hard chrome. Bearing steel and WC–Co balls have been used as rubbing counterparts. The wear is predominantly adhesive for the atmospheric plasma spray (APS) and the electroplated coating. For HVOF coating, wear has been found to occur by localised microfracture. A careful choice of plasma spray parameters yields a coating more wear resistant than the electroplated hard chrome. However, the HVOF coating has always offered the highest wear resistance.