钛酸锶钡粉体晶化过程和物相结构研究

Crystalline procedure and phase structure of BST powders

应用传统陶瓷制备工艺制备出Ba0.6Sr0.4TiO3（BST）粉体，在600—1140℃范围内对粉体按不同温度煅烧，用X射线衍射分析各煅烧温度下制备出粉体的物相结构，用TG／DTA研究了粉体在煅烧过程中的晶化过程．实验结果表明：粉体在600-900℃煅烧过程中出现3个不同的中间相，900℃附近这些中间相基本消失，BST钙钛矿相开始形成，经过1000℃煅烧2．5h，BST粉体已经显示为完全的钙钛矿相，其晶格常数a和c分别为0．3974mm和0．3984mm，晶胞体积为0．0629nm^3．随着煅烧温度的升高，粉体的晶格常数和晶胞体积逐渐减小．

The Ba0.6Sr0.4TiO3（BST） powder was prepared by traditional ceramic processing and calcined at different temperatures between 600 ℃ to 1 140 %, The phase structure of BST powders was analyzed by X - ray diffraction （XRD）, and the crystalline procedure of BST powders during calcining was researched by TG/DTA. The results showed that three different intermediate phases of powders appeared during calcined at 600 - 900 ℃, When the temperature increased to around 900 ℃, these phases were basically disappeared and the perovskite BST began to form. After calcined at 1 000 ℃ for 2.5 h, BST powder was absolute perovskite phase, the lattice constants a and c were 0.3974 nm and 0.3984 nm, respectively, and the unit cell volume was 0. 0629 nm^3. As the calcining temperature increased, lattice constants and unit cell volumes decreased gradually.