超重力反应沉淀法制备的纳米钛酸钡粉体的烧结与介电性能研究

将超重力法制备的纳米钛酸钡粉体在不同温度(700～900℃ )下煅烧,以提高粉体的结晶度,粉体的粒径从40nm增大到80nm。煅烧后的粉体经过干压成型后,在1100℃下保温2h烧结得到的钛酸钡最高室温介电常数为2880,相对密度为90%,晶粒尺寸达到0.70 μm左右。讨论了煅烧温度对粉体的烧结性能、陶瓷的介电性能及微观结构的影响。

Dielectric properties of nano-BaTiO3 powder synthesized by high-gravity reactive precipitation

The dielectric properties of fine-grained barium titanate ceramics that were sintered from a nano BaTiO₃ powder have been investigated. The starting BaTiO₃ powders synthesized by HGRP were calcined at different temperature (from 700℃ to 900℃) to improve their crystallinity, and the particle sizes of the obtained BaTiO₃ powders increased from 40nm to 80nm. These BaTiO₃ powders were sintered at 1100℃ for 2h in air, and the effect of calcining temperature on the sinterability, dielectric properties and the microstructure of BaTiO₃ powders were discussed.The obtained ceramics have the highest permittivity of 2880 at room temperature,with 90% of theoretical density and about 0.70μm grain size.