Nonlinear, quasi-static finite-element calculations are performed for multilayered, electrostrictive, ceramic actuators. Both a stand-alone device and an array of devices embedded in a 2-2 composite are studied. The numerical model is based on a fully coupled constitutive law for electrostriction which uses strain and polarization as independent state variables. This law accounts for the stress dependence of the ceramic`s dielectric behavior and simulates polarization saturation at high electric fields. Two-dimensional plane strain computations are performed for a single actuator constructed from Pb(Mg13/Nb23/)O3-PbTiO3-BaTiO3(PMN-PT-BT). The stress state near an internal electrode tip is computed and a fracture mechanics analysis is performed to assess the device`s reliability. The effect of compressive prestress on the actuator`s induced strain response is also predicted. In a second problem, a 2-2 composite embedded with an array of PMN-PT-BT multilayered actuators is studied with plane stress and plane strain versions of the finite-element technique. A unit cell model containing a single actuator is used to predict the displacement distribution at the surface of the composite under various levels of electric excitation.
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