Fine tungsten carbide powder and process for producing the same

Details Fine tungsten carbide powder and process for producing the same Fine tungsten carbide powder and process for producing the same

2004-08-03

2008-12-16

Hendrickson, Stuart (Department: 1793)

Chemistry of inorganic compounds

Carbon or compound thereof

Binary compound

Reexamination Certificate

active

07465432

ABSTRACT:
A process is provided for producing a fine tungsten carbide powder, which comprises the steps of drying a slurry, which is obtained by mixing an aqueous ammonium tungstate solution with a carbon powder, at low temperature, to form a precursor, mixing a reduction and carburization product, which is obtained by reducing and oxidizing the precursor in an inert gas, with a carbon powder in a proportion required to substantially carburize the entire tungsten component into tungsten carbide (WC), and carburizing the mixture; and a high-performance fine tungsten carbide powder produced by the process, which has an average particle size of 0.8 μm or less and is free of a coarse power having a particle size of more than 1 μm, and which also contains less metal impurities and contains oxygen and nitrogen in a predetermined amount.

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