(1. 中南大学 化学化工学院，长沙 410083；
2. 中国铝业股份有限公司 郑州研究院，郑州 450041)
摘 要: 以Al(OH)3为原料，采用烧结法，运用SEM、XRD、DSC等分析技术，研究了AlF3对γ→α-Al2O3 的相变过程及α-Al2O3显微结构的影响。结果表明：AlF3 可以显著促进亚稳相氧化铝到α-Al2O3的物相转变，在没有添加剂的情况下，γ→α-Al2O3 的相变温度为1 300 ℃，在AlF3的作用下，其相变温度只有1 150 ℃。在没有添加剂的作用下，生成的α-Al2O3是蠕虫状空间网状结晶，固相传质是主要的传质形式，在AlF3的作用下，α-Al2O3是典型的片状结晶，气相传质占主导地位。
关键字: α-Al2O3；相转变速率；显微结构；传质形式
（1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. Zhengzhou Research Institute, China Aluminum Corporation of China Limited, Zhengzhou 450041, China）
Abstract:Using aluminum hydroxide as the starting material, the influences of AlF3 on the phase transformation of γ→α-Al2O3 and microstructure of α-Al2O3 were studied by SEM, XRD, DSC. The results show that AlF3 can accelerate the phase transformation of γ→α-Al2O3. The phase transformation temperature is about 1 300 ℃ without additives, while it is only 1 150 ℃ with the addition of AlF3. The microstructure of α-Al2O3 is verminal without additives, and solid phase diffusion is the main form of mass transfer. With the action of AlF3, the microstructure of α-Al2O3 is plate, and gas phase diffusion is the main form of mass transfer.
Key words: α-alumina; phase transformation rate; microstructure; form of mass transfer
