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

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. (C) 2014 Elsevier Ltd. All rights reserved.