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Herein, the effect of heat treatment on the high‐temperature wear resistance of Ni–Co electroplating coating on copper surface is systematically investigated. Results show that the oxide layer formed on the surface of coating during heat treatment induces the wear mechanism transition of coating. Under the condition without oxide layer formation (heat treatment at 400 °C), the coating suffers severe adhesive wear due to the low hardness caused by grain growth. After heat treatment at 600 °C, the formation of CoO and Co3O4 oxide layers on the surface of coating improves wear resistance, and the wear mechanism changes to oxidative wear and adhesive wear. The density of the oxide layer determines the degree of adhesive wear. As the heat treatment temperature increases (900 °C), the formation of a denser NiCo2O4 oxide layer with higher hardness further inhibits the adhesive wear mechanism of the coating. Until more than 6 h, the formation of scale‐shaped NiCo2O4 and 3CoO·NiO oxide layers significantly improves the wear resistance of the coating and completely eliminates adhesive wear. The wear mechanism is transformed into oxidative wear.

To further clarify the characteristics of plasma-cladded Ni60A coating on copper, the microstructure and wear behavior were analyzed layer by layer. Along the depth direction, the coating can be divided into three regions according to the difference of microstructure: upper, middle and bottom. The phase composition in different regions was the same (including γ-(Cu, Fe, Ni), Cr23C6, CrB and Ni3Si), and there was no obvious difference in the volume fraction of strengthening phases (Cr23C6 and CrB). Due to the stronger load-bearing capacity of larger-size strengthening phases, the wear resistance of middle region was slightly higher than that of upper region. However, the high copper content in bottom region led to a decrease in hardness and resistance to plastic shear, which significantly reduced the wear resistance (2.3 times lower than upper region). Chemical composition had a greater impact on the wear resistance than size and distribution uniformity of strengthening phases.