直流偏压对压力诱导反铁电陶瓷去极化性能的影响

Effect of DC bias on pressure-induced depolarization of Pb(Nb,Zr,Sn,Ti)O_3 ceramics

采用掺铌的锆钛锡酸铅(PNZST)反铁电陶瓷作为研究对象,研究了不同的直流电场作用下,等静压力诱导极化态反铁电陶瓷发生去极化过程(同时发生铁电/反铁电相变)的规律.当极化态样品两端电场强度为6kV/cm时,去极化压力为128.8MPa;当极化态样品两端电场强度为-6kV/cm时,去极化压力为74.2MPa.在与极化电场方向相反的外加电场作用下极化态样品具有较小的去极化压力.讨论了外加直流电场影响极化态反铁电陶瓷去极化压力的内在机理.得到了不同外置电场下的去极化压力,并绘制了该材料的外加直流电场(E)-压力(p)相图.

The polarization and depolarization of antiferroelectric Pb（ Nb, Zr, Sn, Ti）O3 ceramics under dc bias were studied under hydraulic pressure ranging from zero to 250 MPa. It was found that the antiferroelectric ceramic can be induced to a metastable ferroelectric state and that the ceramic at this ferroelectric state can be switched to the antiferroelectric state by using hydraulic pressure. The hydraulic pressure that induces the transition from the ferroelectric to the antiferroelectric states increases with the positive and decreases with the negative dc bias. The electrical energy stored in the poled ceramics at its ferroelectric state releases during the transition from the ferroelectric to antiferroelectric state, which results in a strong current pulse a cross the ceramic. Based on the results, the pressure-electric field phase diagram for polarized PNZST ceramics was established.