Nanostructured WC–Co particles produced by carbonization of spark eroded powder: Synthesis and characterization

Particles of homogeneous elementary composition are formed by spark erosion of a WC–Co hard alloy in a special assembly. The average particle diameter is 4.0 μm, and the specific surface area is 3.33 m2/g. The powder was carbonized for 4 h in CO gas. The particles produced by carbonization consist of a WC frame, with cobalt situated in WC interlayers. The thickness of WC layers in most of the particles ranges from 10 to 200 nm. The microhardness of these particles (HV = 23.7 ± 4.2 GPa) exceeds the microhardness of the initial standard hard alloy (HV = 15.47 ± 1.71 GPa).