Numerical Investigation of the Behavior of FML Composite Plates under Low Velocity Impact

In this article, low velocity impact behavior of fiber metal laminate (FML) composite plates is investigated under three different impact energies (12.7 J, 16.3 J and 24.2 J). Here, three modeling techniques are used. In one of the models the inter-laminar damage is neglected (model without delamination) and in other two models this damage is simulated using cohesive element and cohesive surface models. Cohesive zone theory is used to model inter-laminar damage and Hashin failure criteria with energy dissipation-based damage evolution is used to model intra-laminar damage. In order to define plastic deformation of aluminum components, plasticity data and the Johnson-Cook plasticity model are employed and results accuracy of each model is compared to experimental ones. In the process of research, numerical modeling results in the terms of impact force and permanent deflection are compared and discussed with experimental results. It has been found that for 12.7 J impact energy in terms of impact force, model without delamination has the most precise result and by increasing impact energy force, accuracy of results is reduced. Whereas, two other modeling technique that include inter-laminar behavior, show more accurate prediction in higher impact energies compared to the experimental result. In which, cohesive surface model has the most accurate results. Also, the imposed damage in cohesive element and cohesive surface models are extracted and compared to each other. In addition, the results indicate that the predicted delamination in cohesive element and cohesive surface models are almost similar to each other.