ABRASION, EROSION AND SCUFFING RESISTANCE OF CARBIDE AND OXIDE CERAMIC THERMAL SPRAYED COATINGS FOR DIFFERENT APPLICATIONS

In the area of antiwear coatings, carbide-containing coatings (Cr3C2-NiCr, WC-Co, WC-Ni etc.) and oxide ceramic coatings (Al2O3, Cr2O3 etc.) are applied using different thermal spray processes in the form of individual layers. In many industries these coatings have become technically significant on components where wear and friction can cause critical damage in the form of abrasion, erosion and scuffing together with corrosion. Carbide-containing and ceramic coatings have been produced with different thermal spray processes (atmospheric plasma spraying, vacuum plasma spraying, high velocity flame spraying and detonation gun spraying) for the determination of abrasive, adhesive and erosive wear resistance. Two types of abrasion test, namely an adhesion wear test and an erosion test in water at a high velocity (up to 170 m s-1), were used for the characterization of wear resistance under different conditions. The coatings were also characterized with regard to microstructure, composition and fracture toughness. The influence of the thermal spraying process parameters on the microstructure is presented together with the influence of the microstructure on the behavior of the coatings under simulated service conditions.