Material nonlinear characteristics of the 3203HD PZT wafer under high electric fields

In this paper, material nonlinear behavior of a PZT wafer (3203HD, CTS) under high electric fields and stress is experimentally investigated and the nonlinearity of the PZT wafer is numerically simulated. Empirical functions that can represent the nonlinear behavior of the PZT wafer have been extracted based on the measured piezoelectric strain under stress. The functions are implemented in an incremental finite element formulation for material nonlinear analysis. New definitions of the piezoelectric constant and the incremental strain are incorporated into the finite element formulation for a better reproduction of the nonlinear behavior. With the new definition of the incremental piezo-strain, the measured nonlinear behavior of the PZT wafer has been accurately reproduced even for high electric fields. For validation of the measured nonlinear characteristics and the proposed approach, a PZT bimorph beam actuator has been numerically and experimentally tested. The predicted actuation displacement based on the material nonlinear finite element analysis showed a good agreement with the measured one.