Constitutive Modeling of Controllable Electrostrictive Structronic Thin Shells
Electrostrictive material is one of the key smart materials, with tremendous potentials in many engineering applications, e.g., sonar, actuators, artificial muscles, etc. The (direct) electrostrictive effect of electrostrictive materials is a quadratic dependence of stress or strain on applied electric field and this nonlinear electromechanical effect contributes significant actuation performance as compared with that of conventional piezoelectric materials. A generic electrostrictive thin shell theory and its dynamic electro-mechanical system equations are derived based on a generic double-curvature thin shell defined in the paraelectric phase. Generic mathematical models and permissible boundary conditions of electrostrictive thin shells are defined based on Hamilton’s principle, elasticity theory, Kirchhoff-Love thin shell theory and Gibbs elastic free energy function. Electro-mechanical behaviors and dynamic characteristics of electrostrictive shells are evaluated. Simplifications of the generic electrostrictive shell theory to other common geometries are demonstrated, electrostrictive/dynamic coupling equations derived, and their electromechanical characteristics discussed.