Microstructure evolution, wear and corrosion behavior of WC reinforced CoCrFeNiMn high-entropy alloy composite coatings by induction cladding

In this study, CoCrFeNiMn high entropy alloy (HEA) composite coatings reinforced with different WC particle contents were prepared by induction cladding technology for the first time. The effects of WC particle contents (0–70 wt%) on the microstructure, hardness, wear resistance and corrosion resistance of the coatings were analyzed. The results showed that the coatings prepared by induction cladding exhibited good metallurgical bonding with the substrate. The addition of WC particles led to grain refinement in the CoCrFeNiMn HEA together with second-phase strengthening and solid solution strengthening, improving the microhardness of the coatings. Compared to the average hardness value of 183 HV0.5 for the CoCrFeNiMn HEA coating, the composite coating with 60 wt% WC particle content exhibited the highest average hardness value of 679 HV0.5. The addition of WC particles significantly enhanced the wear resistance of the composite coating, with wear mechanisms including adhesive wear, abrasive wear, fatigue wear and oxidation wear. The composite coating with 60 wt% WC particle content demonstrated outstanding wear resistance, with a specific wear rate value of 0.491 × 10−6 mm3N−1 m−1, representing a reduction of approximately 670 times compared to the CoCrFeNiMn HEA coating. However, the addition of WC particles caused uneven potential distribution within the composite coatings, leading to galvanic corrosion. The WC particles and precipitated carbides increased the defects in the passive film, thus reducing the corrosion resistance of the composite coatings.