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CNA Seminar/Colloquium/Joint Pitt-CNA Colloquium

Gal deBotton
Department of Mechanical Engineering, Ben-Gurion University (Israel)
Title: Electromechanical response, stability, wave-propagation and band-gaps in EAP composites

Abstract: We study the electromechanical response of nonlinearly coupled heterogeneous materials capable of large deformations. The characterization of the deformation of these materials due to electrostatic excitation is initially considered. In the limit of infinitesimal elasticity it is shown that the coupled macroscopic governing equations are identical to the microscopic ones. Application of the results to the class of laminates demonstrates that the electromechanical coupling can be intensified by orders of magnitude. To examine the coupled behavior in finite deformation a finite element code is used. We find that heterogeneity is an origin for instability development. This issue is tackled by superimposing infinitesimal perturbations on the pre-stretched composite. A general criterion for the instability onset is introduced and implemented to a class of anisotropic materials. We also analyze the propagation of waves in electrically pre-stretched laminates. The dispersion relation is determined by making use of Bloch-Floquet theorem and band-gaps are identified.

Date: Friday, October 19, 2012
Time: 1:30 pm
Location: Wean Hall 7218
Submitted by:  David Kinderlehrer