Abstract
It has been demonstrated experimentally that charge implanted composite microstructures exhibit desirable piezoelectricity (with a piezoelectric coefficient d33 higher than 1500 pC/N) and stretchability (with an elastic modulus about 300 kPa). The implanted charge pairs function as dipoles, which response promptly to diverse electromechanical stimulation. Until now, only limited analytical and numerical models have been developed to characterize the complex electromechanical responses of such microstructures. To address the need, an analytical model with key parameters estimated by a finite element model has been built. In this paper, regular column- and wall-type cellular structures with micrometer-sized voids that allow better modeling and optimization are studied, and both 33 and 31 coupling modes are considered. It is demonstrated that cellular structures with higher porosity usually exhibit stronger piezoelectricity and higher stretchability. Furthermore, thickness ratios of the multilayer microstructures are found to be crucial to their characteristics. The physics and electromechanical properties of the charge implanted composite microstructure can be understood and optimized accordingly. As such, they could potentially serve as flexible and sensitive electromechanical materials, and fulfill the needs of a variety of sensor and energy harvesting applications