The elevated temperature oxidation and wear behavior of Fe20Co20Ni20Cr8Mo12B10Si10 high-entropy alloy coating by laser cladding

Abstract

High-entropy alloy coatings show great potentiality in improving elevated temperature oxidation and wear resistance. In this study, Fe20Co20Ni20Cr8Mo12B10Si10 high-entropy alloy coating was prepared on 42CrMo alloy structural steel by laser cladding. The elevated temperature oxidation and wear resistance were investigated at room temperature and elevated temperature (600 °C). The crystal structure of the coating changed from a dual-phase structure consisting of BCC (dominant phase) and FCC phase to a single FCC structure with the production of SiO2, MoO3, Cr2O3 and NiCr2O4 after 600 °C oxidation for 200 h. The oxidation rate of the coating was 1.21 × 10−3 mg/(mm2·h), one fifth that of 42CrMo steel. The tribological properties of the coating shown no significant difference at room and elevated temperature with an average coefficient of friction and the wear rate about 0.46 and 0.02 mm3/N·m, respectively. The oxide film generated on the surface of the coating was dense and uniform, providing excellent oxidation and wear resistance at elevated temperature.

Keywords

• Laser cladding
• Fe20Co20Ni20Cr8Mo12B10Si10
• Microstructure
• Wear resistance
• Oxidation resistance