Microstructure and wear performance of heat treated WC-12Co microwave clad

• We investigate effect of heat treatment on WC-12Co microwave clads.
• Heat treatment beyond 400 °C transforms the amorphous phases into eta carbides.
• Elongated eutectic carbides are undissolved at 400 °C, contribute to high hardness.
• Elongated eutectic carbides reduce depth of wear and friction.

In this study, WC-12Co powder was deposited onto stainless steel substrate using microwave hybrid heating technique. The deposits were then heat treated within a temperature range of 400 °C–900 °C in controlled (argon) atmosphere. In microwave cladding C and W get liberated due to decarburisation of WC and combine with Co to form amorphous phases. Changes in the constituting phases and microstructure due to post heat treatment were investigated using X-ray diffraction and scanning electron microscopy, respectively. Microstructural observations and phase analysis indicated the formation of eta-phases during heat treatment up to 400 °C, which lead to increase in the hardness and wear resistance of the clads. Microhardness examination revealed significant improvement in hardness post heat treatment at 400 °C. The abrasive wear behaviour of the WC-12Co has been correlated with microstructural and phase changes due to post clad heat treatment at various temperatures.