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The aim of the current study was to elaborate and compare abrasive wear resistance of thick coatings deposited with different hardfacing technologies. To produce metal matrix composite (MMC) coatings commercial iron and nickel based powders with recycled hardmetal content of 40 vol. % were studied. For deposition technologies plasma transferred arc (PTA) hardfacing, high-velocity oxy-fuel (HVOF) spraying were used. The microstructure of produced thick coatings was examined, including the distribution of hard phase and homogeneity of metal matrix. Micromechanical properties, including hardness and elastic modulus of features were measured by universal hardness measurements. Furthermore, behavior of coatings subjected to abrasive rubber-wheel wear (ARWW) and impact wear (AIW) tests were studied. Wear resistance of experimental PTA hardfacings at low velocity ARWW and AIW tests notably exceeds that of HVOF sprayed coatings. Wear mechanism dominating at abrasive wear in most cases is the removal of metal matrix due to lower hardness. Assignment of hardmetal waste as initial material can significantly decrease the cost of production, improve the mechanical characteristics of coatings and consequently increase their wear resistance. Results indicate, that the choice of matrix for the same reinforcements can also be as an important factor for combating abrasive wear. Fe-based thick coating, produced by PTA is more wear resistant compared to the Ni-based ones.

Advantages of hard coatings and deposition technologies such as HVOF have opened new opportunities for the production of wear parts operating in an abrasive environment. Thermally sprayed hardmetal coatings are widespread in industrial applications for wear, but not usable under impact wear conditions. To widen the scope of thick hard coating applications, powder coatings, produced by plasma spraying and powder spray-fused coatings using laser remelting, were studied. Nickel-and iron-based self-fluxing alloy powders and WC-Co hardmetal powders were used as spray materials. The microstructure of coatings and the influence of heat treatment on the structure and composition of coatings as well as on the composition of the substrate were studied. The duplex-treated surfaces were tested under the conditions of abrasion and abrasive erosion and impact wear and the mechanisms of coating degradation were analysed. Prospects of coatings, containing thermal spray-fused iron-based metal-matrix WC-Co hardmetal for erosive wear conditions, are demonstrated. Based on the comparative studies of abrasive, erosive and impact wear resistance, recommendations for materials and coatings are formulated.