Mechanical Behavior of Innovative Reinforced Aluminum Foam Panels

Metals foams are attracting great interest in aerospace, automotive and military fields. Particularly, the closed-cells aluminum foams are characterized by peculiar properties, such as low specific weight coupled with high energy absorption capacity, high specific stiffness and strength and reduced thermal and electrical conductivity. For the above reasons, aluminum foams can be effectively used as core of sandwich structures, replacing the traditional honeycomb and polymerbased foams. However, under specific loading conditions, the foam core was proved to collapse because of the bubble-cell structure, so affecting the mechanical performance of the sandwich constructions. Different solutions have been studying in literature to reinforce the foam-based core; for example, the authors in previous studies investigated the possibility to use a metal grid inside the core as a corrugated skeleton, to improve its behavior under compression. Therefore, based on these premises, the aim of this work is to improve understanding of the mechanical behavior of innovative reinforced aluminum foam panels through an experimental approach consisting of three-point bending tests. In particular sandwich structures with and without a corrugated grid structure, acting as skeleton inside the core, were manufactured. The bending properties were estimated also considering two different types of steel grid employed for the corrugated structure and for reinforcing the skins.