Soft impact of GLARE fiber metal laminates

Dynamic response of fully clamped GLARE fiber metal laminates (FMLs) subjected to closed-cell aluminum foam projectile impact has been investigated experimentally and numerically. FMLs with various layup angles are made of glass fiber prepreg and aluminum alloy with identical thickness among each type of layers. The active failure modes of FMLs, including the global deformation and local denting with cracks of the metals, fiber fracture, delamination and interlayer debonding are observed in the experiments. It is shown that the damage degree and deflections of FMLs decrease with increase of the thickness. FMLs of the oblique angle layups have similar deformation and failure modes as the orthogonal layups. Finite element (FE) simulations are performed and are in good agreement with the experimental results. Most kinetic energy of the metal foam projectiles is dissipated by the deformations of the metal layers, the deformations and fracture of the composite layers, debonding and foam compression. The impact resistance of FMLs can be enhanced by increasing the interlayer bonding strength.