Studies on Carbothermal Reduction Nitridation of Alumina in Extended Arc Thermal Plasma

In this paper, carbothermal reduction and nitridation of alumina in an extended arc thermal plasma reactor operating in transferred arc mode is reported. The formation of hexagonal AlN (average particle size approximate to 5 to 7 mu m) has been observed in 5min of processing time. The reaction is completed around 25min of processing time. The reaction mechanism at high temperature has been predicted based on the chemical equilibrium diagram. The phase analysis, morphology, and optical studies of plasma synthesized AlN powder are carried out by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Raman spectroscopy, respectively. The compositional analysis is carried out by electron probe micro-analyzer (EPMA) and energy dispersive X-ray analysis (EDAX).