Fabrication of nanostructured WC–Co coating with low decarburization

•Developed techniques for fabricating nanostructured WC–Co coating.•Simultaneous reduction of decarburization and porosity in cermet coating.•Enhancement of properties of nanostructured coating.

Three kinds of thermal spray powders with different densities and WC particle sizes were prepared using in-situ synthesized nanoscale WC–Co composite powder as raw material. The WC–Co coatings were then fabricated by high velocity oxy-fuel thermal spraying. The phase constitution of the as-sprayed coatings and microstructures of the feedstock particles and the coatings were analyzed. The results show that the coating prepared using powder with a relatively higher density and smaller WC particle size exhibits simultaneously lower decarburization and higher density, and further enhanced hardness. The present study suggests an effective method to fabricate nanostructured WC-based cermet coatings with high properties.