前驱体制备途径对PFN-PMN二元铅基铁电陶瓷性能的影响

Effects of Various Precursor Process Routes on the Properties of Lead-Based Ferroelectric Ceramics in PFN-PMN Binary System

综合运用 ＸＲＤ、ＳＥＭ、ＴＥＭ、ＥＤＳ和介电测量等方法，考察了一步预煅烧法和二步预煅烧法等前驱体制备途径对Ｐｂ（Ｆｅ１／２Ｎｂ１／２）Ｏ３（ＰＦＮ）－Ｐｂ（Ｍｇ１／３Ｎｂ２／３）Ｏ３（ＰＭＮ）二元系铁电陶瓷显微结构和介电性能的影响．研究结果表明，对（１－Ｘ）ＰＦＮ－ＸＰＭＮ二元系而言，在所考查的组成范围内（Ｘ＝０～０.５）；其居里温度与ＰＭＮ的含量近似成线性关系，且随Ｘ的增加，居里温度向低温方向移动.峰值介电常数随Ｘ的增加而降低．（预）煅烧和烧结条件对显微结构和介电性能都有不可忽视的影响．对用一步预煅烧法和二步预煅烧法得到的样品的介电性能和其他性能进行了比较，并对其差异产生的可能机制进行了讨论．

The binary system of Pb(Fe1/2Nb1/2)O-3(PFN)-Pb(Mg1/3Nb2/3)O-3(PMN) was investigated into the effects of different precursor process routes on the microstructrure and dielectric properties by using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersion spetrometer (EDS) and dielectric measurements. It is concluded that for the binary system (1-x)PFN-xPMN, the change of Curie temperature is approximately linear with respect to PMN content in the range of interest (x = 0 similar to0.5). With the increase of x, the Curie points shift to lower temperatures. And the dielectric maximum (epsilon(max)) decreases with increasing x. Both calcining and sintering conditions have non-negligible influence on microstructure and dielectric properties. Dielectric and other properties were compared for samples prepared by single-step and two-step precalcination route and the possible mechanisms leading to the differences were discussed.