Experimental investigation on impact response of aluminum corrugated sandwich beams with empty and pmi foam filling

Two corrugated aluminum sandwich structures with empty and PMI foam filling are proposed to improve the strength and crashworthiness of oil tank structure under impact loading, and to provide substitutes for traditional monolithic counterpart. Aluminum foam projectile impact test is conducted to investigate the dynamic performance of the sandwich beams with the two proposed configurations. High-velocity photography is employed to capture the features of the beam deflecting process. The deflection history at the mid-span of the back face, as well as the deformation and failure modes, is studied for different sandwich beams with same total weight. Experimental results show that when impact velocities are relatively high, the corrugated core of empty sandwiches is significantly compressed and the front face experiences large scale indentation and severe tearing, whereas both core compression and front face tearing in foam-filled sandwiches are significantly reduced as a result of foam filling. The back face deflection of a foam-filled sandwich is nonetheless larger than that of an empty sandwich. From a realistic point of view, the filled sandwich is preferable compared to the empty sandwich.