One-step synthesis of ultrafine WC–10Co hardmetals with VC/V2O5 addition by plasma assisted milling

• Plasma assisted milling is capable of rapidly fabricating W-C-Co-VC nanopowder within only 3h.
• High-performance ultrafine WC-10Co alloys with VC addition are directly produced from the W-C-Co-VC nanopowder.
• The grain inhibiting effect of V2O5 is comparable with VC.

WC–10Co cermets were directly produced from the elemental nanopowders W–C–Co with addition of VC or V2O5, which was prepared by innovative ball milling assisted by the dielectric barrier discharge plasma (denoted as DBDP-milling). By only 3 h of DBDP-milling, the particle size of W, Co, and VC was greatly reduced, and the W flakelets were uniformly coated with graphite nano-sheets. It is the VC addition by DBDP-milling that dramatically refines the microstructure of bulk WC–Co cemented carbides, and some WC grains possess a truncated sector prism shape with both size and thickness less than 100 nm. The ultrafine-grained microstructure is responsible for the improved mechanical properties of hardmetals. Further, the V2O5 addition by DBDP-milling has an identical inhibiting effect as the VC doping on the grain growth of WC during sintering.