Finite element modelling of the impact response of fibre metal laminates under tension preloading

A finite element (FE) model to accurately compute the low energy impact response and impact damage to fibre metal laminates (FMLs) under tension preloading is described. The FE model can predict the initiation and progression of impact damage that includes metal plastic deformation, delamination damage, and debonding along the metal-composite interfaces. The accuracy of the FE model is evaluated using experimental data for an aluminium/glass-epoxy FML. The FML was impacted at different energy levels while preloaded to different tension strain levels. The FE model accurately predicted the peak impact load, impact-time response, absorbed impact energy and bulk deformation of the FML for the different impact energy and preload conditions. The FE model also accurately calculated the amount of plastic deformation damage to the metal sheets and delamination damage to the composite sheet, which were dependent on the tension preload strain.