Microstructure and corrosion resistance of rare earth NiCrMoY alloy coatings

The microstructure and corrosion of rare earth NiCrMoY alloy made by atomisation and oxygen–acetylene flame spray and high-frequency induction remelting technique were investigated by means of scanning electron microscopy, energy spectrum, X-ray diffraction, uniform corrosion of laboratory immersion tests and anodic polarisation curve of three-electrode potentiodynamic scans. The results showed that compared to the coatings of Ni60A, the microstructure of NiCrMoY alloy coatings was finer, some bulk- and needle-like hard microstructures were precipitated, and a new phase MoB was produced. The corrosion rate of NiCrMoY alloy coatings is better than that of Ni60A coatings in HCl, H2SO4, HNO3 and artificial seawater.