Achieving enhanced wear resistance in CoCrNi medium-entropy alloy co-alloyed with multi-elements

This work provides a useful method for the surface application of FCC medium/high entropy alloys. A novel Mo-Nb-B-Si alloyed CoCrNi coating was successfully prepared by plasma cladding. Compared with the CoCrNi coating, its microstructure changed from single FCC phase to FCC, lamellar eutectic phase (FCC and Sigma) and Laves phase. Sigma phase, Laves phase showed higher hardness and Si, Mo, Nb had a solution strengthening effect on FCC matrix, which effectively improved the hardness of the alloyed coating. Wear testing results showed that the wear resistance of the coating was nearly twice as high as that of the CoCrNi coating.