Modeling and interpreting particle shape dependence of electric displacement distribution in the piezoelectric polymer composites

A finite element-based code was developed to capture the effect of particle shape on the electromechanical properties of three typical piezoelectric polymer composites. The electrical energy density and electric displacement distribution patterns were modeled by putting particles with different shapes into the model. To evaluate the reliability of investigations, differential equations were solved using Mori-Tanaka and finite element methodologies, where model predictions were appropriately consistent with each other regardless of particle shape and volume fraction of minor phase. Polymer composites filled with continuous fiber revealed similar electromechanical features irrespective of the piezoelectric nature of polymers. On the other hand, strain- and stress-induced electrical displacement distributions were sensitive to particle shape. The results suggest that densities corresponding to relative strain energy and relative electrical energy of composites containing continuous fiber inclusions are both higher than the analogous values obtained for the systems filled with short fiber and spherical particles. Likewise, the polymer composite with continuous fiber revealed improved electric displacement distribution compared to those filled with the other two types of filler. The truthfulness of the developed model was further ensured by placing multifarious particles into the host polymers, which is of vital importance from application point of view.