The influence of the external stress on the electromechanical response of electrostrictive 0.9Pb(Mg1/3Nb2/3)O3−0.1PbTiO3 in the dc electrical field-biased state

Abstract

The influence of uniaxial compressive stress, T3, applied parallel to the electrical field, on the electromechanical parameters of 0.9Pb(Mg1/3Nb2/3)O3−0.1PbTiO3 ceramics in the dc electrical field-biased state and at temperatures near the dielectric constant maximum Tm was investigated. It was found that T3 reduces both the dielectric constant and polarization level, which results in a reduction of the piezoelectric coefficient with stress. However, the compliance of the material does not show much change with stress. As a consequence, the coupling factor k33 is also reduced with stress. On the other hand, the existence of the local micropolar region in the material causes anomalous changes in the aforementioned properties when the material is subjected to a high electric field, which induces a macropolar state. The transformation of this macropolar state back to a micropolar state under stress involves a large volume strain and results in an enhancement of the hydrostatic piezoelectric response.