Synthesis and Spheroidization of Disperse High-Melting (Refractory) Powders in Plasma Discharge

Résumé

One of the areas of using arc and radio-frequency induction (RFI) plasma in metallurgy is to obtain refractory metals and materials with spherical shape of particles. The main advantages of using spherically shaped particles are high purity of particle surface, high bulk density (minimum surface/volume ratio) and ability to gain control on porous article properties and to separate the particles in fractions. Spherical particles are needed in the formation of powder-metallurgy elements with desired and uniform porosity, which are operated at high temperature, in highly aggressive media and at high velocity fluid flows.
The present work considers the possibilities of using arc and RFI-plasma in metallurgy to obtain high-melting point metals and materials with spherical shape of particles.