Plasma sintering behavior of binderless WC powders

Pure WC powders which does not include a binder phase were consolidated by spark plasma sintering (SPS) process at 1600/spl sim/1850/spl deg/C for 0/spl sim/30 min under 50 MPa. Microstructure and mechanical properties of binderless WC prepared by SPS were investigated. With increasing sintering temperature, sintered density and Vickers hardness of binderless WC increased. The fracture toughness of binderless WC was 7/spl sim/15 MPam/sup 1/2/ according to sintered density and revealed the tendency to decrease with increasing the Vickers hardness. It is found that the binderless WC prepared by SPS at 1750/spl deg/C for 10 min under 50 MPa showed nearly full densification with fine-grained structure and revealed excellent mechanical properties of high hardness (/spl sim/ HV 2400) and considerably high fracture toughness (/spl sim/ 7 MPam/sup 1/2/).