Summary: | Two typical coatings (nickel-based and iron-based) were successfully fabricated on AISI 304 stainless steel via cold metal transfer process as alternative materials with superior wear and cavitation erosion resistance, respectively. Scanning electron microscopy, X-ray diffraction and electron backscattering diffraction were performed to characterize the morphologies, phase composition and crystallographic textures. Subsequently, tribology, cavitation erosion as well as corrosion tests were carried out to analyze the applicability of the coatings in various environments. Experimental results showed that the coatings exhibited few defects and an excellent metallurgical bonding with the substrate, and possessed the strong textural features. The microhardness of the coatings was ∼ 3 times higher than that of the substrate, and the microhardness of nickel-based coating was more stable than that of the iron-based one. Combining with the cumulative volume/weight loss and morphologies, the wear and cavitation erosion resistance of the coatings and substrate were compared, and failure mechanisms were proposed. It was found that the cumulative volume/weight loss of the coatings are one order of magnitude lower than that of the substrate. The combination of toughness and fine dispersed carbides had guaranteed the higher wear resistance of iron-based coating, while the formed massive phases of nickel-based coating played a significant role in the cavitation erosion and corrosion resistance.
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