Design of the structure of 1-3 piezocomposites by considering the interpillar vibrational modes

When a piezocomposite vibrates in a thickness mode, interpillar modes of vibration are likely to occur between lattice-structured piezoceramic pillars and a polymer matrix, which significantly diminishes the performance of the piezocomposite. The conventional method for designing 1-3 piezocomposite structures has not considered these interpillar modes. In this study, a new method of optimizing the structure of 1-3 piezocomposites has been developed to maximize the electromechanical coupling factor of thickness modes while preventing the occurrence of interpillar resonant modes. The volume fraction of piezoceramics and the aspect ratio of the piezocomposite were the design variables that were optimized. The genetic algorithm was used to optimize the structure, and the finite element method was used to analyze the interpillar modes.