锡酸铅对铌镁酸铅-钛酸铅铁电陶瓷性能的影响

Effects of PbSnO_3 on the properties of Pb(Mg_(1/3)Nb_(2/3))O_3-PbTiO_3 perroelectric ceramics

采用固相法合成(0.90-x)Pb(Mg1/3Nb2/3)O3-0.10PbSnO3-xPbTiO3(PMN-PSn-PT)铁电陶瓷.研究了(0.90-x)PMN-0.10PSn-xPT铁电陶瓷的结构、介电、铁电和压电性能.在PMN-PT陶瓷中加入PSn后,由于Sn在合成过程中的变价行为导致了第二相Sn2Nb2O7的产生.根据XRD分析确定了(0.90-x)PMN-0.10PSn-xPT体系的准同型相界(MPB)位于x=0.36附近,进而结合介电温谱分析得到了(0.90-x)PMN-0.10PSn-xPT的部分低温相图.PSn加入到PMN-PT陶瓷中,降低了PMN-PT铁电陶瓷的压电活性,最大值位于0.52PMN-0.10PSn-0.38PT组分处(390pC/N).极化样品的介电温谱上没有观察到三方-四方相变温度点,说明PSn的加入使PMN-PT陶瓷的MPB变窄和竖直,因而PSn的加入可以提高PMN-PT铁电陶瓷的实际使用温度.

Ferroelectric ceramics （0.90-x）Pb（Mg1/3 Nb2/3） 03-0. 10PbSnO3-xPbTiO3 （PMN-PSn- PT） were synthesized by solid solution reactions, and their structure, dielectric, {erroelectric and piezoelectric properties were investigated. The second phase of Sn2 Nb2 O7 had been caused by the change of valence of Sn. A morphotropic phase boundary（MPB） region was determined around x= 0. 36 based on the XRD analysis. And then the low-temperature phase diagram was constructed based on dielectric spectra and XRD data. The piezoelectric coefficients for PMN-PT ferroelectric ceramics was reduced by the addition of PSn. 0. 52PMN-0. 10PSn-0. 38PT ferroelectric ceramics have maximum piezoelectric coefficients（390 pC/N）. It was noteworthy that dielectric spectra of the poled samples don＇t show any rhombohedral-tetragonal phase transition temperature. It was indicated that the MPB region becomes narrow and linear, which was attributed to the addition of PSn. Therefore, the application temperature of PMN-PT ferroelectric ceramics could be increased by the addition of PSn.