Experimental and numerical analysis of the crushing response of metallic 3D double-arrow sandwich panels with optimal production capability

The outstanding properties of lattice structures make them an excellent choice for use as a core in sandwich panels. They can greatly improve the strength, energy absorption, and shear resistance of sandwich panels used in various industries. This paper introduces a new innovative approach to producing metallic sandwich panels with 3D Double-Arrow Head (3D-DAH) cores to improve energy absorption and crushing response. The proposed method proves cost-effective when compared to traditional manufacturing processes and produces a final cell geometry that closely replicates previous double-arrow structure designs. Additionally, this method can be adapted for large-scale production with relative ease. Through the experimental tests, it was found that increasing the L parameter of the 3D-DAH cell raised the height of the sandwich panels which reduced the stability of the structure under compressive axial load. The failure modes became primarily asymmetrical, and the buckling initiation force reduced. Moreover, when the angles of the large and small beams in the double-arrow cell were closer together, the plateau stress area of the sandwich panel became more stable and wider, resulting in increased absorbed energy. A numerical model was developed within ABAQUS, and after validating the numerical results, the response surface method was used to predict structural behavior and optimize the geometrical parameters of 3D-DAH according to minimum peak crushing force (PCF) and maximum specific energy absorption (SEA).