The mechanical response of metallic sandwich beams under foam projectile impact loading

The dynamic response of the clamped sandwich beams was investigated by impacting the beams at mid-span with metal foam projectiles. Effects of applied impulse, face-sheet thickness and core thickness on the impact resistance of sandwich beams are discussed. Using strain gauge measurement technique, the deformation mechanism of sandwich beams was analyzed in the paper. The results indicate that the structural response is sensitive to the configuration of sandwich structures. Based on the experiments, corresponding finite element simulations have been undertaken using the LS-DYNA software. A good agreement has been obtained between the numerical and experimental results. The deformation and failure modes of sandwich beams under impact loading are presented, i.e. large inelastic deformation, core compression and core shear with interfacial failure. Numerical results also show that the velocity-time histories of the mid-span of the front and back sheet of sandwich beams are related to not only core strength but also core thickness. The research results are of worth to the theoretical prediction of the dynamic response of metallic sandwich beam.