Simultaneously enhancing wear and corrosion resistance of HVAF-sprayed Fe-based amorphous coating from Mo clad feedstock

High-performance Fe-based amorphous (FA) composite coating was successfully fabricated on 304 stainless steels via employing a novel feedstock of FA powders partially clad with molybdenum (Mo). The microstructure, tribological and corrosion behavior of FA/Mo composite and pure FA coating coating were comparatively investigated. Experimental results show that with 20 vol. % Mo incorporation, FA/Mo composite coating became remarkably denser with porosity of 0.46 +/- 0.12 % and attained a 35 % increase in fracture toughness. As a result, compared to the pure FA coating, superior wear resistance including lower specific wear rate and coefficient of friction (COF) were achieved in the composite coating. In addition, the dominant wear mechanism of coating changed from abrasive wear to oxidative wear. Furthermore, due to its favorable amorphous composite microstructure with less pores and more hydrophobic surface, the FA/Mo coating simultaneously obtained better corrosion resistance. The present findings may provide a valuable strategy to prepare FA protective coating for industrial application.