Effect of uniaxial stress on the electromechanical response of ⟨001⟩-oriented Pb(Mg1∕3Nb2∕3)O3–PbTiO3 crystals

The ⟨001⟩-oriented 0.7PMN–0.3PT and 0.67PMN–0.33PT crystals are characterized under uniaxial stress and electric field loading above the coercive field. Strain-electric-field and electric-displacement-electric-field hysteresis loops are measured at various compressive stresses showing a notable effect of stress on the electromechanical coupling. A moderate uniaxial stress can advance their electromechanical properties. Stress-strain curves are run at zero electric field, showing that depolarization for ⟨001⟩-oriented 0.7PMN–0.3PT crystal begins at 7MPa, while as little as 3MPa for 0.67PMN–0.33PT crystal, placing a severe limitation in actuator applications.