Processing of Tungsten Nanopowder into a Micropowder Consisting of Spherical Particles

Abstract—A method for producing tungsten powder consisting of spherical microparticles with dimensions of 20–50 μm is considered when processing granular tungsten nanopowder in a flow of argon electric arc thermal plasma. Experimental studies of plasma chemical synthesis of tungsten nanopowder in a plasma reactor with a limited jet flow during the interaction of tungsten trioxide with a flow of hydrogen-containing plasma generated in an electric arc plasma torch were carried out. The conditions of spray drying and the properties of a suspension consisting of tungsten nanoparticles were determined experimentally, ensuring the production of mechanically strong nanopowder microgranules of rounded shape with a homogeneous internal nanostructure that does not contain cavities, with the yield of microgranules with a size of less than 60 μm at the level of 65%. The influence of the parameters of the plasma processing of nanopowder microgranules in the thermal plasma flow on the degree of spheroidization and the microstructure of the resulting particles was established.