Tungsten Borides Prepared from Tungsten-Containing Concentrate via Exposure to Microwave Plasma

• Published in: Inorganic materials 2023-06, Vol.59 (6), p.576-582
• Main Authors: Balakhonov, D. I., Nikolenko, S. V.
• Format: Article
• Language: English
• Subjects: Borides; Chambers; Chemistry; Chemistry and Materials Science; Electrons; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; Microwave plasmas; Plasma; Refractory compounds; Scheelite; Tungsten compounds; Waveguides
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1134/S0020168523060031

— We have studied the structure of tungsten borides prepared from a tungsten-containing mineral concentrate using an experimental microwave arc plasma system. A configuration of such a system has been proposed which includes a microwave generator, indirect plasma source, and reaction chamber. We address some issues pertaining to the positioning of the plasma source on the waveguide chamber and the formation of a microwave plasma flow in the confusor zone, followed by the exit of the flow to the concentrator zone, and describe processes involved in the plasma synthesis of tungsten borides. A process is proposed for the preparation of a mixture based on a multicomponent mineral (scheelite) concentrate from the Russian Far East and results are presented on the physicochemical properties of tungsten borides prepared via local exposure to a high-energy plasma flow with a power density from 10 to 100 kW/cm 2 . In our experiments, the WB, WB 2 , W 2 В, and W 2 В 5 compounds have been obtained. We assess the potential of using plasma technologies for preparing boron- and tungsten-based refractory compounds from scheelite concentrate.