Characterization of Exponential Cohesive Zone Model for Fracture Assessment of De-Bonded Composite Panels

Abstract

Composite structures are prone to delamination/de-bond and effective tool to simulate de-lamination is cohesive zone model. Cohesive zone model uses multiple adhesive failure parameters. The influence of adhesive parameters on the delamination and fracture of Double cantilever Beam, subjected to Mode-I loading through finite element simulations is studied usingExponential Cohesive Zone Model (ECZM). Influence of Normal stress (σ), normal deflection (δn) and tangential deflection (δt) on the de-bond propagation is examined.From the analysis it is found that the tangential deflection (δt) has negligible impact on Mode-I loading and fracture of the specimen. Significant effects are seen for the perturbation of Normal stress (σ) and Normal deflection (δn). A Finite element based ECZM for composite layer (HTS/M18) with EPG 2601 adhesive is proposed. The model is validated by comparing with test data.