0.115BiGaO3-（0.885-x）BiScO3-xPbTiO3高温压电陶瓷的制备及电学性能研究

利用氧化物合成法制备了0.115BiGaO3-（0.885-x）BiScO3-xPbTiO3（BGSPTx）（x=0.56-0.62）铁电陶瓷.X射线衍射分析（XRD）表明,当PbTiO3含量（x）大于60%时,BGSPTx具有纯的钙钛矿结构。当x〈60%时,体系存在微量杂相。随着PbTiO3含量的增加,BGSPTx由三方相演变到四方相,三方-四方准同型相界位于x=0.58附近。在准同型相界附近,BGSPTx陶瓷的压电常数d33、机电耦合系数、剩余极化Pr都达到最大值,分别为272pC/N,42%,24μC/cm^2。介电常数-温度特性曲线测试表明,BGSPTx陶瓷在MPB附近（x=0.58）居里温度TC高达482℃。实验结果表明,BGSPTx陶瓷是一种优良的高温压电换能器和传感器材料。

Preparation and electrical properties of high temperature piezoelectrics 0.115BiGaO_3-(0.885-x)BiScO_3-xPbTiO_3

0.115BiGaO3- （ 0.885-x ）BiSeO3-xPbTiO3 （ BGSPTx, x=0.56-0.62 ） ceramics were conventional mixed oxide processing. X-ray diffraction shows that pure perovskite structure could x〉60%, whereas the formation of secondary phase occurred for x〈60%. A rhombohedral to tetragonal fabricated using be obtained for phase transition was determined in the vicinity of x=0.58. For composition near x=0.58, BGSPTx ceramics show enhanced piezoelectric coefficient d33, planar coupling coefficient kp, and remnant polarization Pr of 272 pC/N, 42%, and 24 μC/cm^2, respectively. The temperature dependence of dielectric constant of BGSPTx ceramics were performed in the temperature range of 25-550 ℃, and BGSPTx ceramics show a high Tc up to 482℃ for x=0.58. The high Tc of BGSPTx ceramics with the high piezoelectric properties suggested those future high-temperature applications.