电场诱导PZST陶瓷反铁电-铁电相变

ELECTRIC FIELD-INDUCED ANTIFERROELECTRIC-FERROELECTRIC PHASE TRANSITION OF PZST CERAMICS

研究了PZST陶瓷电场诱导反铁电－铁电相变,当外加电场大于相变临界参数EAFE-FE时，样品由反铁电态诱导为铁电态，并在宏观性能上产生突变：极化强度和纵向应变分别由零跃变到大约30μC／cm2和0．3％，介电常数下降50％．利用直流偏压原位X射线衍射表征了相变时晶格结构的变化，结果表明，伴随着相变的发生，晶格结构由反铁电四方相转变为铁三方相.

Electric field-induced antiferroelectric-ferroelectric phase transitioh of PZST ceramics was studied. Upon application of an electric field EAFE-FE, PZST ceramics undergoes an antiferroelectric to ferroelectric phase transform, associated with an abrupt change in macroscopic properties.Polarization and longitudinal Strain increase suddenly from zero to 30μC/cm2 and 0.3% or so, respectively and dielectric constant decreases 50% at phase transition. In situ X-ray diffraction patterns under different dc bias fields showed that the crystal structure changes from tetragonal antiferroelectric phase to rhombohedral ferroelectric phase.