Electromechanical response of 1-3 piezoelectric composites with hollow fibers

A finite element model is developed to characterize the complete electromechanical response of piezoelectric composite materials with hollow fibers and to obtain a quantitative assessment of the relative effects of the introduction of porosity and a piezoelectric second phase in a piezoelectric matrix material. Fifteen characteristic composites are identified for each of the two model ceramic-based and polymer-based matrix systems (i.e., barium titanate and polyvinylidine difluoride) by systematically varying the volume fractions of porosity and the second phase (i.e., lead zirconate titanate). It is demonstrated that the fundamental properties and the piezoelectric figures of merit of the piezoelectric composites generally exhibit greater sensitivity to the presence of porosity in the electroelastically stiffer ceramic-based systems while the piezoelectrically active second phase has a dominant influence in the electroelastically compliant polymer-based systems.