Microstructure and properties of (CrMnFeCoNi) ₉₇ Mo ₃ plasma cladding coating

A (CrMnFeCoNi) 97 Mo 3 HEA coating was processed by plasma cladding. The microstructure and phase composition of the coating were characterized by a combination of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The properties were tested by nanoindentation, the friction and wear tester and the electrochemical workstation. The phase composition of the coating still maintains a single FCC structure. There were slightly incompletely melted Mo particles in the coating. Partial segregation of Mo forms σ phases (CrMo) at grain boundaries. EBSD analysis indicated that the coating was mainly composed of columnar crystals, and the maximum texture strength reaches 6.596. The mechanical property tests revealed that the microhardness of the coating was 177.8 H V, the average nanohardness was 2.56 GPa, and the average tested elastic modulus was 207.95 GPa. The average friction coefficient of the coating was 0.5849. The main wear mechanisms were oxidative wear and abrasive wear. Electrochemical corrosion studies have shown that the addition of Mo enhances the corrosion resistance of the coating. The self-corrosion current density (3.46 × 10 −5 mA cm −2 ) is lower than that of pure CrMnFeCoNi coating, and the corrosion rate reaches 0.353 mm/a.