Finite Element Modeling of Local Damage in Kevlar/Carbon Fiber Sandwich Under Low Velocity Impact

Impact properties of carbon fiber and Kevlar or hybrid (3K carbon fiber/1500 Denier Kevlar) combination sandwich composite plates were numerically investigated in this study. The goal of this research was to define the change in impact properties as results of replacing the carbon fiber layer on the impact-side face sheet with combinations of carbon fiber/Kevlar or carbon fiber/hybrid. Information on impact energy and maximum impact force obtained from previous experiments were applied to validate the model input properties. The models were then used to characterize the mechanism of the reduction in the global stiffness of the sandwich plate due to the sequence of the damage in the foam core and the face sheet corresponding to the variation of the laminate mixture and loading energy. Results from this study could be of assistance to determining structure integrity with respect to the composite combination under impact load.