Numerical analysis of porous piezoelectric materials

Abstract

Three-dimensional finite element models based on unit-cell approach are developed to characterize the complete electromechanical properties of: (i) zero-dimensional (3-0), one-dimensional (3-1) and three-dimensional (3-3) type porous piezoelectric structures made of lead zirconium titanate (PZT-7A) and relaxor (PMN-PT based) ferroelectrics (RL); and (ii) 3-3 type porous piezoelectric foam structures made of several classes of piezoelectric materials such as barium sodium niobate (BNN), barium titanate (BaTiO3) and relaxor (PMN-PT based) ferroelectrics (RL). In this thesis, finite element software named ABAQUS is used to characterize the electromechanical response of 3-0, 3-1 and 3-3 type porous piezoelectric structures. Appropriate boundary conditions are invoked for various porous piezoelectric structures (i.e. 3-0, 3-1 and 3-3 type) to ensure that the electromechanical deformation response of the unit-cell, under conditions of electrical and mechanical loading, is representative of the entire porous piezoelectric structures. Overall, this thesis demonstrates that the microstructural features such as porosity connectivity, porosity aspect ratio, porosity volume fraction, foam shape, and material selection play significant roles on the electromechanical properties and the figures of merit of porous piezoelectric structures.