Microstructure and wear behavior of plasma cladded Ni-based alloy coating on copper under different preheating temperature

Abstract

To clarify the influence of process parameters on the microstructure and wear resistance of coating, a series of Ni60 A alloy were deposited on copper surface by plasma cladding under different preheating temperatures. The obtained coatings were new alloy materials formed by the dilution of Ni60 A alloy with Cu, and their microstructure and properties were closely related to the dilution rate. With the increase of preheating temperature, the dilution rate of the coatings increased obviously, which led to a gradual increase of the copper content in the γ-(Cu, Fe, Ni) solid solution phase, thus resulting in compositional inhomogeneity and performance deterioration of the coating. From 500 °C to 800 °C (preheating temperature), the average hardness of the coating decreased from 680.3 HV0.1 to 406.6 HV0.1, and the wear resistance reduced by 2.8 times. The wear mechanism of the coating changed from abrasive wear to the combination of abrasive wear and adhesive wear. For practical applications, to ensure the excellent wear resistance of the coating, the preheating temperature should be controlled at a low level.

Keywords

• Plasma cladding
• Copper
• Ni-based coating
• Preheating temperature
• Microstructure
• Wear resistance