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.