Hard Metal Waste Recycling by the Atmospheric Direct Current Arc Plasma

Abstract

The paper presents the results of experimental studies on the preparation of fine powder materials of the tungsten-carbon system in a plasma of a direct current (DC) arc discharge initiated in an open-air environment. The initial reagents for the synthesis of powders containing tungsten carbide was waste of worn hard metal elements based on tungsten carbide and cobalt, which had been previously ground and subjected to oxidation. The process of obtaining non-oxide materials during the generation of a direct current arc plasma in the presence of carbon and tungsten is possible due to the intense generation of carbon monoxide and carbon dioxide gases, which shield the reaction volume from atmospheric oxygen. Synthesis products were analyzed by X-ray diffraction analysis, scanning electron microscopy and elemental analysis, tungsten carbides WC, W2C with hexagonal structure, tungsten-cobalt carbide and graphite-like materials were identified as synthesized polymorphs.