Phase and Microstructural Transformation of BaTiO3 Powder Synthesized by Solid-State Reaction

BaTiO3 powder with small particle size and high tetragonality was synthesized by a sanding solid-state phase method with domestic submicron BaCO3 and TiO2 as raw materials. We also studied the effects of calcination temperature, heating rate and holding time on the average particle size and tetragonality of BaTiO3. The results show that the reaction mechanism for the synthesis of BaTiO3 by solid phase reaction can be divided into two stages: when the calcination temperature is lower than 900 degrees C, BaCO3 and TiO2 first form cubic phase BaTiO3. When the calcination temperature rises to 900 degrees C, the cubic phase BaTiO3 begins to transform into a tetragonal phase. Ultrafine BaTiO3 powder with a particle size of 180.7 nm and a tetragonality (c/a) of 1.0086 is prepared at a calcination temperature of 900 degrees C, a heating rate of 5 degrees C/min, and a 5 h incubation. This work provides a good research idea for the preparation of high performance BaTiO3 powder used for ultra-thin MLCC.

以国产亚微米级BaCO3和TiO2为原料,采用砂磨固相法合成粒径小、四方性高的BaTiO3粉体,同时研究煅烧温度、升温速率及保温时间对BaTiO3平均粒径和四方性的影响.结果 表明,通过固相反应合成BaTiO3的反应机理可分为两个阶段:当煅烧温度低于900℃时,BaCO3和TiO2首先形成立方相的BaTiO3,当煅烧温度升至900℃时,立方相BaTiO3开始向四方相转变.在升温速率为5℃/min,煅烧温度为900℃保温5h时,制备出粒径为180.7 nm,四方性(c/a)为1.0086的超细BaTiO3粉体.该工作为制备超薄层MLCC用高性能BaTiO3粉体提供了较好的研究思路.