Chemical vapor synthesis (CVS) of tungsten nanopowder in a thermal plasma reactor

Nanosized tungsten powder was synthesized by a thermal plasma process using ammonium paratungstate (APT) as the precursor. The injected precursor was vaporized in the plasma flame and the subsequent reduction of the vaporized precursor produced nanosized tungsten powder. The effects of H2 concentration, plasma torch power, and the flow rate of plasma gas on the product properties were investigated and particle size was determined. From the results, nanosized tungsten powder of particle size less than 50 nm was obtained by the thermal plasma process.