Carbon doping to improve the high temperature tribological properties of VN coating

• The sp2C–C, sp3C–C and VC phase were found in the VCN coating.
• Microstructure of VN coating was significantly affected by the C-doped.
• The hardness increased significantly when the carbon is doped into VN coating.
• Tribological properties of VN coating were strongly affected by the C-doped.
• The VCN coating exhibited better tribological properties than VN coating.

VN and VCN coatings were deposited by the cathodic arc ion plating technique. Microstructures, mechanical properties and tribological properties of both coatings in ambient air were comparatively investigated. Results showed that the sp2C–C, sp3C–C and VC phases were found in VCN coating. The VCN coating exhibited lower friction coefficients and wear rates than VN coating in different temperatures. The lower friction coefficient and better anti-wear property of the VCN coating were closely related to the self-lubricating amorphous carbon and V2O5 phase, indicating its potential application as a lubricant coating for tribo-components under high temperature conditions.