Effect of energy on the phase composition of the product of arc discharge synthesis in the tungsten-carbon system obtained in a self-shielding autonomous gas environment

The paper presents the results of experimental studies on the preparation of ultrafine powder materials of the tungsten-carbon system in the plasma of a direct current arc discharge initiated in an ambient air. According to the results of X-ray diffractometry, transmission electron microscopy, scanning electron microscopy, and elemental analysis, the product identifies micro-sized and nanoscale crystalline objects that are carbon graphite-like materials gC, tungsten carbides WC and W2C with a hexagonal structure, tungsten W with a cubic structure. As a result of a series of experiments, the possibility of influencing the phase composition of the synthesis product by the amount of energy supplied, which is linearly dependent on the duration of the arc discharge, was established. In this case, tungsten oxide phases were not found in the composition of the synthesis products within the framework of the applied analytical techniques. 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. Thus, in the framework of the presented work, the possibility of controlling the phase composition of the product of vacuumless arc synthesis in the tungsten-carbon system by changing the duration of the discharge burning at a constant direct current was shown for the first time.