Microstructure and tribocorrosion properties of Ni-Based composite coatings in artificial seawater

NiAl matrix composite coatings were prepared using atmospheric plasma spraying (APS). The mechanical and tribocorrosion properties of the NiAl matrix composite coatings, incorporated with Cr₂C₃ and Mo, were investigated, and the synergistic effect between corrosion and wear was studied in detail. The microhardness of the composite coating improved from 195.1 to 362.2 HV through the addition of Cr₂C₃ and Mo. Meanwhile, the Cr₂C₃ and Mo phases were distributed uniformly in the composite coatings. The X-ray diffraction (XRD) peaks of Ni-based solid solution slightly shifted to the right after adding the Mo. This was probably due to the solid solution of Mo into the matrix. The NiAl-Cr₂C₃-Mo composite coating had the lowest corrosion current density, wear rate and friction coefficient of 9.487 × 10^-6 A/cm² , 3.63 10^-6 mm³/Nm, and 0.18, in all composite coatings as well as showing excellent tribocorrosion properties.