SPARK PLASMA SINTERING OF NANOSTRUCTURED TUNGSTEN CARBIDE AND CARBIDE ALLOYS
The consolidation of nanosized pure tungsten carbide and carbide alloy powders by spark plasma sintering has been studied. Pure WC sintering modes within the temperature interval (1400–1950)C and heating rates from 25 to 2400C/min have been investigated. Nanostructured specimens with a record hardness of 3180 HV and a satisfactory fracture toughness of K1c=4.5–6.5 MPam1/2 have been obtained. The article determines the dependences of density, hardness, and grain structure of WC-8 wt.% Co alloys with TaC/VC inhibitors on the sintering temperature, heating rate and solid-state sintering time. Nanostructured WC-8 wt.% Co specimens with high values of hardness (17–19 GPa) and fracture toughness (more than 10 MPam1/2) have been obtained.