Bending and polarization switching of piezoelectric laminated actuators under electromechanical loading

The static electromechanical displacement and polarization switching properties of piezoelectric laminated actuators under three point bending have been investigated theoretically, numerically and experimentally. A laminated beam theory is expanded to allow for piezoelectric/metal/piezoelectric actuator, and the effects of electromechanical loading on the displacements of the actuators are analyzed. A nonlinear three-dimensional finite element procedure which allows to compute the polarization switching behavior is also proposed. Three point bending tests are used to validate the numerical predictions, using laminated actuators made with thin soft lead zirconate titanate (PZT) piezoelectric layers and a thin metal sheet, and comparison is made between numerical results and experimental data.