Synthesis of Hafnium Carbide Powder in Atmospheric Arc Plasma

The paper presents a method, implemented for the first time, for the thermal synthesis of hafnium carbide powder using a DC arc discharge initiated in the open-air atmosphere. Based on the results of the series of experiments, the dependences of the current strength of the power source and the time of thermal treatment on the phase composition of the resulting powder product were established. Required parameters have been determined to ensure the synthesis of a powder containing ~98 mass % of the cubic phase of hafnium carbide: heat treatment of the initial mixture containing the stoichiometric ratio of hafnium to carbon for 60 s at a current of 220 A. The size, shape, and substructure of particles of the synthesized carbide are characterized. The differential thermal analysis carried out in an oxidizing medium showed that the obtained hafnium carbide powder is oxidized most intensively at a temperature of ~700°C.