Effect of thermal treatment on wear performance of HVOF coatings for mechanical applications

Thermally sprayed tungsten and chromium carbide based coatings are widely applied on mechanical components in various industrial applications where, wear resistance is most important requirement. The present research work is focused on the tribological properties of WC-10Co-4Cr and Cr3C2-25NiCr HVOF coatings in the range between temperatures of 20°C to 400°C. A duplex stainless steel specimens were considered as substrate, and the effect of different heat treatments was evaluated in terms of microhardness, wear resistance, scratch resistance and microstructural evolution by GDOES. At the end of the experimental campaign the Cr3C2-25NiCr coating results suitable for higher temperature (300°C to 400°C) applications for a longer period, while WC-10Co-4Cr coating provides better performances at lower temperature.