Multi-objective analysis of hybrid CFRP I-Beam subjected to low-velocity impact

To investigate the impact behavior of CFRP I-beams, this study incorporates aluminum plates to develop a hybrid structure with metal. A numerical model based on 3-D Hashin failure criterion and bilinear cohesive zone theory was established. Following validation, the mechanical behavior of the CFRP I-beams was systematically analyzed using a multi-objective approach. The results indicate that the aluminum plate thickness played a significant role in the impact response of hybrid CFRP I-beams. As the targeted thickness increases to 1 mm, the failure load increases by 24.3 %, while the corresponding displacement was decreased to 46.3 %. Notably, the configuration in which the aluminum plate is placed on the web exhibits superior impact performance. A peak load of 6933.5 N is achieved, an increase of 35.7 % compared to the pure CFRP, while the displacement decreased by 51.7 %. Finally, the study clarifies the coupled failure mode involving fiber fracture, matrix crushing, and delamination propagation.