Binderless WC and WC-VC materials obtained by pulsed electric current sintering

WC and WC VC materials without metallic binder addition were densified by pulsed electric current sintering (PECS) in the 1600-1900 degrees C range. The clensification mechanism, microstructure and mechanical properties of the pure WC and VC-doped WC carbides were investigated. The densification of WC-VC materials was accompanied with the formation of a cubic (V,W)C solid solution. Although no abnormal WC grain growth was observed, the (V,W)C grains were observed to grow rapidly with increasing VC content. A maximum Vickers hardness (HV10) of 27.39 GPa in combination with an indentation toughness of 4.38 MPa m(1/2) was obtained for the PECS pure and 1 wt% VC doped WC grades. The hardness was found to linearly decrease down to 21.41 GPa with further addition of VC up to 16 wt%, with a slightly decreased fracture toughness. (C) 2007 Elsevier Ltd. All rights reserved.