Effect of Laminate Configuration and Impactor's Mass on the Initial Impact Damage of Graphite/Epoxy Composite Plates Due to Line-Loading Impact

Abstract

An investigation was performed to study the effect of stacking sequence, thickness, and impactor's mass on the impact damage of graphite/epoxy laminated com posites due to low-velocity impact. The major focus of the study was concentrated on the initial damage and the corresponding impact energy with respect to these parameters. Ex periments were performed using specially designed line-nose impactors by which the re sulting impact damage and failure mode of the composites could easily be inspected. Ac cordingly, the velocities of the impactors causing initial impact damage in the composites were determined, and the effects of the laminate configuration and the mass of the impac tor on the damage were established. Numerical simulations based on the model, which was developed previously, were also performed in order to understand the basic mechanics and mechanisms governing the phenomena observed from the experiments. Based on the study, it can be concluded that the change of stacking sequence significantly influences the impact damage much more than the change of thickness. Initial impact damage is also very sensitive to the mass of the impactor, and both velocity and mass of the impactor have to be specified in order to adequately characterize impact damage in composites.

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