Electrostrictive effect in ferroelectrics: An alternative approach to improve piezoelectricity

Electrostriction plays an important role in the electromechanical behavior of ferroelectrics and describes a phenomenon in dielectrics where the strain varies proportional to the square of the electric field/polarization. Perovskite ferroelectrics demonstrating high piezoelectric performance, including BaTiO₃, Pb(Zr_1-xTi_x)O₃, and relaxor-PbTiO₃ materials, have been widely used in various electromechanical devices. To improve the piezoelectric activity of these materials, efforts have been focused on the ferroelectric phase transition regions, including shift the composition to the morphotropic phase boundary or shift polymorphic phase transition to room temperature. However, there is not much room left to further enhance the piezoelectric response in perovskite solid solutions using this approach. With the purpose of exploring alternative approaches, the electrostrictive effect is systematically surveyed in this paper. Initially, the techniques for measuring the electrostrictive effect are given and compared. Second, the origin of electrostriction is discussed. Then, the relationship between the electrostriction and the microstructure and macroscopic properties is surveyed. The electrostrictive properties of ferroelectric materials are investigated with respect to temperature, composition, phase, and orientation. The relationship between electrostriction and piezoelectric activity is discussed in detail for perovskite ferroelectrics to achieve new possibilities for piezoelectric enhancement. Finally, future perspectives for electrostriction studies are proposed. © 2014 AIP Publishing LLC.