In certain lead zirconate titanate compositions, the antiferroelectric (AFE) phase can be driven to the ferroelectric (FE) phase by electric field, and the induced FE phase can either revert to AFE or remain FE upon removal of the electric field. This results in a double or single hysteresis loop, respectively. To further explore the effects of the FE-AFE phase transition on electrical energy storage and conversion, two types of AFE ceramics were fabricated, and the effects of compressive stress on the AFE-FE phase transition were investigated. Compressive stress suppresses the volume increase associated with the AFE-FE transition, thus hindering the phase transition. Compressive stress also hinders polarization orientation in the FE phase, thus increasing the field necessary to achieve saturation polarization. For AFE compositions displaying a double hysteresis loop, the electrical energy storage performance can be enhanced by compressive stress. For the AFE compositions with a single hysteresis loop, the remanent polarization of the induced FE phase decreased and the coercive field did not change much within the range of compressive stress applied. In addition, the remanent polarization was reduced by 50% under a compressive stress of 126 MPa, indicating that this composition is a candidate for mechanical-electrical energy conversion.

The ferroelectric and ferroelastic properties of lead-zirconate-titanate (PZT) based stack actuators have been characterized at temperatures down to 25 K and under various levels of constant compressive stress. Experiments indicate that the coercive field and magnitude of strain at the coercive field display an inverse relationship with temperature. A factor of 5.5 increase in coercive field, and a factor of 4.3 increase in strain is observed at 25 K in comparison to the room-temperature conditions. This information was used to induce non-180° domain wall motion in the material through the application of electric fields at or near the coercive field. The change in remanent strain accompanying these effects was shown to increase in magnitude as temperature decreased, reaching values of 2000 ppm at 25 K. This behavior was also shown to be temporally stable even under compressive loads. Additionally, it was demonstrated that the material can be returned to its original strain state through a repolarizing electric field. This switchable behavior could be exploited for future set-and-hold type actuators operating at cryogenic temperatures.

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