The nonlinear behaviour of a piezoelectric wafer: Constitutive equations and simulation

A piezoelectric wafer has been widely used as a key component of actuators or sensors of a layer type. According to recent research, the piezoelectric wafer behaves in a nonlinear way under excessive electro-mechanical loadings. In the present paper, a simple one-dimensional model for the nonlinear behaviour of a piezoelectric wafer near a poled state is proposed, based on the principles of thermodynamics and a simple viscoplasticity theory. The constitutive model is rate-dependent as well as nonlinear. The predictions of the developed model are compared with experimental observations.