Study of multiple impact behaviors of CFRP based on peridynamics

Impact damage of carbon fiber reinforced polymers (CFRP) composites is a common form of damage in composite structures. In this work, a model integrating the structure model of composites, failure model and contact model with friction based on ordinary state-based peridynamics (PD) theory is developed to simulate multiple impacts of CFRP. The simulation results of single impact are in good agreement with the existing experimental and finite element simulation results, validating the proposed PD model. Then the effects of impact energy, stacking sequences and impact angles on the CFRP damage behaviors under multiple impacts are thoroughly investigated. Multiple high energy impacts may cause a non-linear increase in the amount of damage. The peanut-shaped stress distributions induced by impact along different directions are typical of the stress responses, which usually correspond to different fiber directions. Moreover, the laminates with stacking sequences of different fiber directions have a better impact damage resistance, as they can hinder the propagation of stress waves across the layers. In addition, as the impact angle increases, the stress and damage become more pronounced. The insights gained shed light on the repeated impact damage mechanisms of CFRP.