Modeling the viscoelectroelastic behavior of PVDF/PZT-5A composites for sensing and actuation applications

Our study presents the modeling of the effective viscoelectroelastic behavior of a composite material, where PVDF is an anisotropic piezoelectric matrix and PZT-5A is incorporated in the matrix as piezoelectric long fibers or spheres. Both materials exhibit viscoelectroelastic properties and their combination offers interesting multifunctional capabilities. A homogenization scheme (based on the Mori-Tanaka micromechanics modeling) is carried out to understand how both material phases interact within the composite behavior. Frequency analysis is also performed to assess the composite's response under varying conditions and effective viscoelectroelastic properties are evaluated to simulate its dynamic behavior. The incorporation of PZT-5A inclusions significantly affects the piezoelectric behavior of the composite, especially its spherical-like shape, resulting in an enlarged hysteresis loop. However, the enlargement is not recommended for sensing purposes, as it introduces energy losses, reduces sensitivity, and compromises precision. In contrast, the actuating behavior of the composite remains relatively unaffected by the addition of PZT-5A inclusions, with the hysteresis loop showing no notable changes, ensuring stable and reliable actuation performance. The study also highlights the disappearance of the hysteretic response at relatively high frequencies. Our work provides valuable insights into the interplay of PVDF and PZT-5A in viscoelectroelastic composites, highlighting challenges and opportunities for optimizing their performance. Our findings contribute to the development of advanced materials for applications requiring tailored sensing and actuation behavior, especially in aeronautic applications.