DEVELOPMENT OF HIGH-VELOCITY OXYGEN-FUEL SPRAYING TECHNOLOGY FOR METAL-CERAMIC COATINGS FOR STRENGTHENING AND RESTORATION OF MILITARY EQUIPMENT COMPONENTS

This work presents the development and experimental validation of a technology for producing WCCo metal-ceramic coatings by high-velocity oxygen-fuel (HVOF) spraying, intended for strengthening and restoring components of military equipment. The coatings were deposited on 12Kh18N10T stainless steel substrates at various spraying distances (300-400 mm). The microstructure, phase composition, surface roughness, microhardness, as well as the tribological and corrosion properties of the obtained coatings were investigated. It was established that the spraying distance has a decisive effect on the formation of the coating structure and its service properties. The optimal spraying regime ensures the formation of a dense lamellar structure with minimal porosity, preservation of the primary WC carbide phase, and limited decarburization to W₂C. It was shown that the microhardness of the coatings is 6-7 times higher than that of the base steel, while the friction coefficient and corrosion rate are significantly reduced compared to the substrate. The obtained results confirm the prospects of WC-Co HVOF coatings for improving the wear resistance, corrosion resistance, and operational reliability of military equipment components operating under high mechanical loads and aggressive environments.

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