3D LASER FORMING OF METAL FOAM SANDWICH PANELS

Metal foam sandwich panels have been 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 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 knowledge about the bending mechanisms translates to 3D deformation, and whether the combination of process parameters that were identified for 2D laser forming are still appropriate. Moreover, the impact qf the laser scan length was determined by comparing different scan patterns that achieve the same 3D geometries. It was shown that 3D deformation could be induced for both the bowl and saddle shapes, the two most fundamental non-Euclidean geometries. The amount qf laser-induced bending and in-plane strains vary depending on process conditions and thus 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.