Low-Temperature Spark Plasma Sintering of Pure Nano WC Powder

For the first time we have demonstrated the densification of high-purity nanostructured (davg approximate to 60 nm) tungsten carbide by High Pressure Spark Plasma Sintering (HPSPS) in the unusually low temperature range of 1200 degrees C-1400 degrees C. The high-pressure sintering (i.e., 300MPa) produced dense material at a temperature as low as 1400 degrees C. In comparison with more conventional sintering techniques, such as SPS (80MPa) or hot isostatic pressing, HPSPS lowered the temperature required for full densification by 400 degrees C-500 degrees C. High Pressure Spark Plasma Sintering, even in absence of any sintering aid or grain growth inhibitor, retained a very fine microstructure resulting in a significant improvement in both hardness (2721 HV10) and fracture toughness (7.2MPam1/2).