DENG Qihuang, SHEN Xiangfen, HAN Bin, DU Shiyu, DING Zhihui, HUANG Qing
(Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences. Ningbo 315201, Zhejiang, China)
Abstract: AlON powders were synthesized by high temperature carbothermal reduction and nitridation using starting powders of α-Al2O3,γ-Al2O3 and activated carbon in N2 atmosphere. And the influence of the crystal structure of alumina, the ratio of alumina and carbon powder,synthesis temperature, and holding time on the purity of AlON powders was studied. The XRD and SEM analysis results indicated that impurities such as alumina and aluminum nitride remained when the sintering temperature was lower than 1900 °C, and the AlON powder with high crystallinity, uniform particle size, high purity was obtained when sintered at 1900 ℃ with two hours holding time. When the carbon content was 5.6% and the nitrogen flow was 4 L/min, the AlON powder with more than 98% purity was obtained. The comparison between γ-Al2O3 and α-Al2O3 showed that γ-Al2O3was more conducive to the formation of AlON powder.
Key words: AlON powder; carbothermal-reduction and nitridation; synthesis