Effect of Y on Microstructure and Properties of Al_0.8FeCrCoNiCu_0.5 High Entropy Alloy Coating on 5083 Aluminum by Laser Cladding

Abstract

To improve the surface properties of 5083 aluminum, Al0.8FeCrCoNiCu0.5Yx (x = 0, 0.05, 0.1, and 0.2) high-entropy alloy coatings were prepared by laser cladding. The phase structure and microstructure of the Al0.8FeCrCoNiCu0.5Yx coatings were characterized by XRD and SEM. The tribological properties of the coating were tested by a friction and wear tester. An electrochemical workstation tested the corrosion resistance of the coating. The results show that when Y content is less than 0.2, the Al0.8FeCrCoNiCu0.5Yx coating is in the FCC1, BCC1, and BCC2 phases. When Y is added to 0.2, the coating appears rich in the Y phase. With the increased Y content, the hardness of the coating can increase. The average hardness of Y0, Y0.05, Y0.1, and Y0.2 are 479HV0.2, 517HV0.2, 532HV0.2, and 544HV0.2, respectively. Microstructure evolution leads to an increase in the hardness of the coating. The effect of Y on the wear resistance of the Al0.8FeCrCoNiCu0.5Yx coatings is consistent with the hardness. Al0.8FeCrCoNiCu0.5Y0.2 coating has the lowest wear rate, at is 8.65 × 10−6 mm3/Nm. The corrosion current density of Al0.8FeCrCoNiCu0.5Y0.05 and Al0.8FeCrCoNiCu0.5Y0.1 coatings is in the order of 10−8, which is less than Al0.8FeCrCoNiCu0.5Y0.2 and Al0.8FeCrCoNiCu0.5. The performance of each component coating is superior to that of the substrate.

Keywords

• laser cladding
• high entropy alloy
• microstructure
• wear and corrosion