Wear resistance of laser remelted thermally sprayed coatings

• Published in: Estonian journal of engineering Vol. 15; no. 4; pp. 318 - 328
• Main Authors: Surzhenkov, A, Kulu, P, Tarbe, R, Mikli, V, Sarjas, H, Latokartano, J
• Format: Journal Article
• Language: English
• Published: 01.12.2009
• DOI: 10.3176/eng.2009.4.09
• ISSN: 1736-6038

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.