Finite element modeling and experimental validation of macro-fiber composite with sandwich structure

Macro-fiber composite(MFC) boasts good flexibility, strong environmental adaptability, and high driving force, which has driven its extensive adoption in fields like aerospace and navigation. To resolve the conflict between computational accuracy and cost in traditional MFC finite element modeling methods, a sandwich structure based MFC finite element modeling method is proposed. Firstly, considering the contribution of cross copper electrodes to the stiffness of MFC, a finite element modeling method for MFC based on the sandwich structure of "electrode layer-active layer-electrode layer" is proposed. Then, the ANSYS-APDL software is used to establish the sandwich finite element model of MFC, and its free strain and blocking force under actual working conditions are calculated to verify the rationality of the established finite element model. Finally, a "piezoelectric-structure" coupled finite element modeling of a cantilever beam with an attached MFC actuator is established, followed by numerical simulation and experimental validation. Results reveal that compared to the traditional homogenization finite element modeling method, the proposed sandwich structure based finite element modeling method markedly enhances the simulation accuracy of MFC driving characteristics. Moreover, it effectively cuts computational costs compared to the micro-scale fine-grained finite element modeling method, making it highly valuable for practical engineering applications.