Tribological Performance of a Ni-Based Composite Coating in Artificial Seawater

Abstract

NiCrAlY and NiCrAlY-Mo coatings were fabricated by atmospheric plasma spraying (APS). The corrosion-wear performance of the coatings was investigated in artificial seawater and the synergistic mechanism between wear and corrosion were evaluated in detail. Results showed that the diffraction peaks of Ni3Al shifted to the right and the microhardness of the coating was improved from 329.8 HV to 342.5 HV with adding the Mo element. Meanwhile, the NiCrAlY-Mo coating had a lower friction coefficient, with a wear rate of 0.26 and 3.69 × 10−6 mm3/Nm, compared to the NiCrAlY coating with a wear rate of 0.37 and 4.67 × 10−6 mm3/Nm. The NiCrAlY coating had severe corrosion and the corrosion mainly occurred in grain boundary. Adding the Mo element, the Mo element was distributed in the grain boundary and the coating had a lower corrosion rate and visibly slighter corrosion. The NiCrAlY-Mo coating had excellent corrosion-wear properties in artificial seawater.

Microstructure and Tribocorrosion Properties of Ni-Based Composite Coatings in Artificial Seawater

“…Firstly, the composite coatings were polished until the composite coating surface roughness was below 0.5 μm. The tribocorrosion tests have been described in detail elsewhere [34]. Figure 3 shows the SEM morphologies of spray powders.…”

Corrosion and Wear Behavior of WC–10Co4Cr Coating under Saturated Salt Drilling Fluid

“…Generally, they not only have to transfer huge bit weights and withstand great torsional stress, but they also suffer from erosion, corrosion, and wear during the work process [ 4 , 5 , 6 ]. Drilling fluid could cause the significant erosion and corrosion of a drill pipe, especially saturated saltwater, which is usually applied as drilling fluid in permafrost and salt rock drilling [ 1 , 7 , 8 , 9 , 10 , 11 ]. Moreover, the diameter of the pipe joint is usually larger than that of the drill pipe, resulting in significant wear.…”