Effect of Mo on phase composition, microstructure and tribological property of TiC reinforced plasma sprayed coatings

Abstract

Two kinds of TiC reinforced wear resistant coatings with or without the addition of Mo were prepared by plasma spraying. Ultrafine TiC powders with sizes varying from 5 to 15 μm were introduced as the reinforcement phase and NiCr alloy as the binder phase. Phase composition and microstructure of the as prepared coatings were characterised by X-ray diffraction and scanning electron microscopy. Wear behaviour of the TiC reinforced coatings was also investigated using a ring-on-block tester. Results showed that the TiC reinforced coatings adhered well to the substrate and exhibited dense structure with low porosity, even though oxidation occurred during spraying. Wear tests indicated that the sliding wear performance of the NiCrMo–TiC coating was better than that of the NiCr–TiC coating at different forces under the same experimental conditions.

Keywords:

• TiC
• Plasma spraying
• Cladding structure
• NiCr–TiC coating
• NiCrMo–TiC coating