Modeling the large deformation and fracture of polymer-metal-polymer film composites – Part Ι: Constitutive behavior

Abstract

The utilization of polymer-metal-polymer film (PMPF) is widespread due to its exceptional mechanical ductility, chemical stability, and impermeability to air. Nevertheless, the intricate manufacturing process and the multi-layered metal-polymer composition of this composite film contribute to its anisotropic mechanical attributes, posing challenges in modeling large deformations and fractures. In part I of this study, we mainly focus on modeling the constitutive behavior of PMPF.

PMPF's stress-strain response displays a distinct crossover characteristic not found in any isolated constitutive models. This study proposes a layered model that amalgamates Hill 48 elastoplastic and orthotropic Fung hyperelastic behaviors to account for the internal structure of the composite film. To expedite model calibration, we establish an optimization-based method, integrating an analytical solution for the layered model's uniaxial behavior in diverse orientations. Moreover, a parametric study into the layered structure subjected to punch loading furnishes insights for parameter identification, mitigating potential solution multiplicity. Calibration involves uniaxial tensile tests at distinct material orientations and punch tests. Through comparison of experimental and finite element outcomes spanning multiple loading conditions for two commercial PMPFs, the validity of the approach is demonstrated. This endeavor lays the foundation for more profound exploration into the fracture behavior of this composite material.