Effect of graphene oxide on CoCrFeNi high-entropy alloy coatings prepared by the electrodeposition method

Abstract

The performance advantages of high-entropy alloy (HEA) have become a consensus. However, the current preparation methods are mostly focused on thermal processing methods, and the research on the preparation of HEA coatings using electrochemical technology is generally rare. Therefore, in this study, the CoCrFeNi HEA coating was synthesized by electrodeposition technology and the effect of graphene oxide (GO) concentration on the microstructure and tribological property of the HEA coating was further studied. The results showed that during the electrodeposition process, the four atoms of Co, Cr, Fe and Ni were co-deposited to form the HEA coating with a face-centered cubic crystal structure. The introduction of GO did not change the crystal structure of HEA coatings, and GO was also co-deposited with metal atoms to form the HEA-GO composite coating. Meanwhile, GO was distributed in composite coatings in the form of being encapsulated by the metal layer. The addition of GO improved the compactness of HEA coating and reduced its surface roughness. The increase in GO concentration helped to inhibit the formation of stress-induced cracks on the surface of the composite coating, and significantly enhanced the wear resistance of HEA coating. When the GO concentration was 0.2 g/L, the wear resistance was the best. The wear form of HEA composite coatings was independent of GO and its concentration, and was dominated by abrasive wear.