Effect of Cu addition on the microstructure and tribological performance of Ni60 directional structure coating

The Ni60/15wt.%Cu coating with directional structure was prepared by composite technology of flame spraying, induction remelting and forced cooling, and the effect of Cu on the microstructure, phase, hardness and wear performance of Ni60 coatings was investigated. The results show that the addition of Cu makes the microstructure of Ni60 directional structure coating more compact, and Cu is mainly enriched within the crystal grain, resulting in the formation of Cu_3.8Ni as bonding phase. Compared with Ni60 coating with directional structure, the Ni60/Cu coating with directional structure shows lower hardness, lower friction coefficient and lower wear rate, which indicate that the element Cu can enhance the antifriction performance of Ni60 directional structure coating effectively.