3D Laser Forming of Metal Foam Sandwich Panels

Abstract

Metal foam sandwich panels have been the subject of many concept studies, due to their exceptional stiffness, light weight, and crash absorption capacity. Yet, the industrial production of the material has been hampered by the fact that it is challenging to bend the material into practical engineering shapes. Only recently, it has been shown that bending of metal foam sandwich panels is possible using lasers. It was also shown that the material can be bent into Euclidean (2D) geometries, and the governing laser-induced bending mechanisms were analyzed. This study was focused on laser forming of metal foam sandwich panels into non-Euclidean (3D) geometries. It was investigated whether the bending mechanisms and process parameters identified for 2D laser forming translate to 3D deformation. Additionally, the impact of the laser scan length was determined by comparing different scan patterns that achieve the same 3D geometries. It was shown that laser forming could induce 3D deformation necessary for both bowl and saddle shapes, the two fundamental non-Euclidean geometries. The amount of laser-induced bending and in-plane strains vary depending on process conditions and the governing bending mechanisms. Lastly, the laser scan length was shown to become more important for metal foam sandwich panels, where the panel thickness tends to be large.