Plasma spray processing of Al2O3/AlN composite powders

A novel method is proposed to prepare Al2O3/AlN composite powders. The comp osite powders were synthesized by direct nitridation of Al2O3 powders in Ar /N-2 plasma. The processing characteristics were studied. The results show that the particle size of the initial materials, the nitrogen plasma gas ho w rate and the power of the plasma generator an important factors that infl uence the phase composition of the Al2O3/AlN composite powders. Post treatm ent of the Al2O3/AlN composites in nitrogen atmosphere was carried out. Mic rostructure analysis showed that the composite powders are spheroids, with the small particle size AlN formed on the surface of the Al2O3. (C) 1999 El sevier Science S.A. All rights reserved.