Wear and corrosion resistance of WC-reinforced nickel-based alloy coating for aircraft landing gears

Nickel-based alloys are commonly used as corrosion-resistant matrix materials in marine environments, but they exhibit low hardness and poor wear resistance. To enhance the wear and corrosion resistance of nickel-based coatings, Hastelloy C276 composite coatings with WC content (10-50 wt.%) were fabricated on the substrate surface using high-velocity oxygen-fuel (HVOF) spraying. The surface morphology, phase structure, tribological properties, corrosion resistance, and underlying mechanisms of the coatings were investigated using X-ray diffraction, scanning electron microscopy, nanoindentation, Vickers hardness testing, tribological wear testing, electrochemical workstation analysis, and X-ray photoelectron spectroscopy.Fluid flow process simulation was employed to optimize the spraying parameters. The results demonstrate that as the WC content increased from 0 to 50%, the coating porosity gradually rose, while the wear rate of the composite coatings decreased by 95%.With increasing WC content, the corrosion potential of the composite coatings remained largely unchanged, while the magnitude of the corrosion current decreased from 10 -4 to 10 -5 A/cm 2 . The corrosion resistance of the coatings initially improved and then deteriorated.When the WC content exceeds 30%, crevice corrosion occurs at pores during the polarization process, which damages the passive film, accelerates the consumption of the Co binder phase, and reduces the coating's shielding effectiveness against Cl - .