Patent ID: 7465432

Claim:
A tungsten carbide powder comprising (a) an average particle size as measured by the Fischer Subsieve Sizer process of 0.8 μm or less, (b) a maximum particle size in a particle size distribution as measured in accordance with ASTM B430-79 of 1 μm or less, (c) the content of tungsten based on the component excluding a non-metal component being at least 99.9% by weight, (d) the content of nitrogen and that of oxygen in crystal lattices being respectively within a range of 0.08-0.30% by weight and 0.10-0.60% by weight and (e) a lattice constant of an a-axis and that of a b-axis being respectively within a range of 0.29020-0.29060 nm and 0.28380-0.28420 nm.