High temperature wear performance of laser-cladded FeNiCoAlCu high-entropy alloy coating

High temperature wear is a common phenomenon, but in the field of high-entropy alloys, there are limited literatures on the wear behavior of laser-cladded high-entropy alloy coatings at elevated temperature. In this work, the wear performance of laser-cladded FeNiCoAlCu high-entropy alloy coating at room temperature, 200 °C, 400 °C, 600 °C and 800 °C were investigated in detail. The phase constitution and microstructure of laser-cladded FeNiCoAlCu high-entropy alloy coating were analyzed by XRD, SEM, EPMA and TEM. The results show that the synthesized FeNiCoAlCu high-entropy alloy coating is composed of FCC and BCC solid solution phases with a typical uniform dendrite microstructure, and the phase constitution of inter-dendritic region and dendritic region are Fe-rich BCC and Cu-rich FCC solid solution, respectively. The high-temperature XRD and DSC results indicate that the laser-cladded FeNiCoAlCu high-entropy alloy coating has a good thermal-stability below 780 °C. The laser-cladded FeNiCoAlCu high-entropy alloy coating also has a good wear performance at high temperature, which is mainly attributed to the formation of oxide films on the surface of the coating. The wear mechanisms are dominated by abrasive wear and oxidative wear.