An investigation of the influence of powder particle size on microstructure and hardness of bulk samples of tungsten carbide

Bulk tungsten carbide samples were prepared by consolidating tungsten carbide powders using plasma pressure compaction. Three different powder particle sizes were chosen and the samples were obtained by consolidating the particles under conditions of pulse and no-pulse. Microstructural observations and density measurements provide sufficient evidence for the presence of porosity even after consolidation at 1500 °C. Regardless of initial powder size, results reveal that pulsing of the powders prior to consolidation resulted in higher density and microhardness values compared to those obtained by consolidating the powders under no-pulse conditions. The influence of initial powder particle size and electrical pulsing on microstructure, including the presence and distribution of porosity, cracks and particles, density and microhardness are detailed.