One of the applications of ammonium paratungstate is - to prepare submicron spherical tungsten powder. For example, some researchers have prepared submicron spherical W powder using ammonium paratungstate as a raw material through the circulatory oxidization-reduction method.
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Ammonium Paratungstate Application - To Prepare Submicron Spherical Tungsten Powder Through Circulatory Oxidization-Reduction Method
Violet tungsten oxide was prepared with pure ammonium paratungstate in argon gas. Tungsten powder was obtained from violet tungsten oxide through deoxidation in hydrogen gas (rate of purity: 99.99%, dew point: -40 °C), and tungsten powder was oxidized in the air. Tungsten oxide was reduced to tungsten powder in hydrogen gas. The samples were characterized with the laser particle size distribution measuring instrument and the electron probe scan instrument. The results show that submicron tungsten powder can be obtained through circulatory oxidation twice and reduction three times. The percentage of the particle size distribution of submicron spherical tungsten powder is 95.73% between 0.1 μm and 1.0 μm, and its BET is 1.082 m2/g.