Uniaxial stress and temperature dependence of field induced strains in antiferroelectric lead zirconate titanate stannat ceramics

The electric field induced antiferroelectric-ferroelectric phase transforma tion of polycrystalline lead zirconate titanate stannate (PZST) was investi gated under prestress conditions at various temperatures. Lanthanum- and ni obium-modified compositions of PZST with varying titanium content were prep ared. The field induced strains of the ceramics were studied. The measured hysteresis loops indicate that the antiferroelectric-ferroelectric phase tr ansformation depends on temperature, as well as on mechanical stress. For e xample compositions of niobium-modified PZST, which are in a ferroelectric state without pressure, can be transformed progressively into an antiferroe lectric phase, by a pressure up to 30 MPa. Antiferroelectric compositions o f both Lanthanum and Niob modified PZST can show either increasing or decre asing strain under the influence of a compressive stress. This depends on t he composition of the sample and the strength of the pre-stress. (C) 1999 E lsevier Science Limited. All rights reserved.