SrBi2Ta2O9铁电陶瓷的制备及其Ca掺杂研究

采用聚合物前驱体法制备了单一铋系层状钙钛矿相SrBi2Ta2O9粉体,研究了不同烧成温度对SrBi2Ta2O9陶瓷相结构和介电、铁电性能的影响。结果表明,随着烧成温度的升高,晶粒沿c轴择优取向趋势增强;不同烧成温度下陶瓷介电常数和损耗均随频率升高而降低,1000℃时陶瓷有最大介电常数和较小的损耗,且陶瓷有较大的剩余极化值和较小的矫顽电场,分别为3.884μC/cm2和25.37kV/cm。不同Ca掺杂量掺杂后,SrBi2Ta2O9陶瓷的介电常数、损耗和剩余极化值均显著降低。

Preparation and Research on Ca Doping of SrBi2Ta2O9 Ferroelectric Ceramics

SrBi2Ta2O9 powder with pure bismuth-layer perovskite phase was prepared by polymeric precursor method.The influence of sintering temperatures to the dielectric and ferroelectric properties of SrBi2Ta2O9 ceramics were studied.The results showed that the degree of c-axis preferred orientation of ceramic grains increased with the rising of sintering temperature.Dielectric constant and dielectric loss of ceramics sintered in different temperatures all decreased with the increasing of frequency and dielectric constant was maximal and dielectric loss was smaller when sintering temperature was 1 000 ℃.At the same time,ceramics have bigger polarization and smaller electric field,which were 3.884 μC/cm2 and 25.37 kV/cm respectively.Dielectric constant,dielectric loss and remanent polarization of SrBi2Ta2O9 ceramic all reduced significantly after Ca-doping with different doped quantity.