Spark 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 1600~185$0^{\circ}C$ for 0~30 min under 50 MPa. Microstructure alid 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 7~15 MPa $m^{1/2}$ depending on the sintered density and decreased with increasing the Vickers hardness. It is found that the binderless WC prepared by SPS at 175$0^{\circ}C$ for 10 min under 50 MPa showed nearly full densification with fine-grained structure and revealed excellent mechanical properties of high hardness (~HV 2400) and considerably high fracture toughness (~7 MPa $m^{1/2}$).