摘要
利用溶胶 -凝胶方法制备了BaTiO3凝胶 ,然后经过不同的退火处理 ,制备了BaTiO3微晶陶瓷。XRD证实了在 110 0℃ ,BaTiO3微晶存在明显的四方相。利用热力学分析的差减微分方程和非等温Johnson -Mehl-Avrami(JMA)方程对BaTiO3微晶的四方 -立方相变的动态过程进行了分析 ,并对其相变过程用修正的JMA方程进行了具体描述 ;其相变活化能为 170～ 190kJ/mol;相变指数为 1,说明BaTiO3微晶的四方
The BaTiO 3 microcrystal was fabricated by sol-gel method with annealing process. The existence of cubic-tetrahedral transition of BaTiO 3 microcrystal at the temperature of 1 100 ℃ is demonstrated by XRD and analyzed actively by thermodynamic method. The cubic-tetrahedral transition is described by the improved JMA equation. The activation energy is 170—190 KJ/mol and the transition index is 1. It is concluded that the cubic-tetrahedral transition is the first law transition because exponent of the transition is equal to one.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2003年第5期441-444,共4页
Journal of The Chinese Ceramic Society
基金
国家重点基础研究发展项目 (G19990 64 5 0 8)
南京师范大学材料科学实验室资助项目
关键词
钛酸钡
微晶
相交
热力学
溶胶—凝胶法
barium titanate
microcrystal
thermodynamics
phase transition
sol-gel method
