METHOD FOR PRODUCING HIGH PURITY PULVERIZED CARBONIZED TUNGSTEN POWDER WITHOUT NECESSITATING GRINDING PROCESS

摘要

PROBLEM TO BE SOLVED: To provide a method for producing high purity pulverized carbonized tungsten powder without necessitating a grinding process. SOLUTION: This method for producing high purity pulverized carbonized tungsten powder comprises a process (a) of blending an aqueous solution of ammonium metatungstate or ammonium tungstate of purity >=99.9 wt.% with carbon powder (C) of purity >=99.9 wt.% so as to compound in atomic ratio C/W of 3-4 and making slurry, a process (b) of drying the slurry at a low temperature and preparing powdery raw material, a process (c) of subjecting the powdery raw material to thermal reduction treatment in nitrogen atmosphere and forming a reduction reaction product comprising primarily WC in composition formula and comprising W2 C and metal W in the remaining, a process (d) of blending the reduction reaction product with the carbon powder (C) of purity >=99.9 wt.% so as to compound in such a proportion that the W component is carbonized to WC of atomic ratio 1: 1, and a subsequent process (e) of subjecting the reduction reaction product to carbonation treatment in hydrogen atmosphere and producing high purity pulverized carbonized tungsten powder.