Effect of Sm2O3 particles on microstructure and properties of FeCoNiCrMn composite coating by laser cladding

In this work, FeCoNiCrMn high entropy alloy (HEA) coating and xSm2O3/FeCoNiCrMn (x = 0 wt%, 1 wt%, 2 wt%, 3 wt%) composite coating were prepared on the surface of 45# steel by laser cladding technology. The microstructure, phase, microhardness, wear resistance and corrosion resistance of Sm2O3/HEA composite coating were described in detail. The results show that the addition of Sm2O3 powder reduces the crack sensitivity of HEA composite coating, and the Sm2O3/HEA composite coating is mainly composed of FCC phase, Co5.24Sm0.97 phase and Fe7Sm phase. Due to the addition of Sm2O3 powder, the microstructure of the coating is refined, and the grain size is reduced. When the content of Sm2O3 is 2%, the hardness of the HEA composite coating is the highest, which is 15.85% higher than that of the HEA coating. With the increase of Sm2O3 content, the wear resistance and corrosion resistance of HEA composite coating increase first and then decrease. When the Sm2O3 content is 2%, the optimal wear resistance and corrosion resistance are achieved, and meanwhile the surface residual stress of HEA composite coating is the smallest.