Study on mode I interlaminar fracture toughness of laminated plates considering interface angle

Abstract

Multidirectional laminates are more widely used in practical engineering, and their fiber bridging characteristics are more obvious than unidirectional laminates. Due to the deficiency of research on the relationship between interface angle and interlaminar fracture toughness of multidirectional laminates, the numerical model of interface mode I fracture toughness of multidirectional laminates related to interface angle is modified by analyzing the difference between steady-state fracture toughness and initial fracture toughness of each interface. Meanwhile, the mode I interlaminar fracture toughness of multidirectional composite laminates under five interface modes is studied. Based on the finite element software, the cohesion model is established and verified. The analytical results are in good agreement with the experimental data, and the modified model can better verify the relationship between interface angle and interlaminar fracture toughness. At the same time, the fiber bridge force in the process of delamination along different interfaces is calculated, which provides a basis for the modified model.