Effect of ZrB₂ on the Microstructure and Wear Resistance of Ni-Based Composite Coating Produced on Pure Ti by Laser Cladding

Abstract

ZrB₂-reinforced Ni-based composite coating was fabricated on pure Ti substrate by laser cladding. The effect of ZrB₂ doping on the microstructure and tribological properties of conventional NiCrBSi composite coating was investigated. It was found that the microhardness and wear resistance of pure Ti substrate are greatly improved after laser cladding. It is remarkable that the ZrB₂ phase could further enhance the conventional NiCrBSi coating and generate higher hardness. During friction, due to the ceramic nature of ZrB₂, that is, ultra-high melting point and hardness, the adhesive wear could be alleviated that occurs in conventional Ni-based coating, resulting in a better wear resistance. Thus, it is concluded that the incorporation of a ZrB₂ phase is an effective and attainable way to improve the tribological properties of conventional Ni-based composite coatings.

KEY WORDS:

• Abrasive Wear
• Coating
• Wear Resistance
• Titanium
• ZrB₂-Enhanced Ni-Based Coating

ACKNOWLEDGEMENTS

The authors thank the Ministry of Science and Technology of China (project of the 863 plan, Grant No. 2006AA03A219) and the Chinese Academy of Sciences (Project of Light in West China 2006) for financial support.

Review led by David Burris