Design of Additively Manufactured 3D Lattice Cores of Sandwich Panels

This study analyzes 3D truss-based lattice cores in sandwich panels subjected to localized transversal loads using analytical methods. Compared to the common sandwich theories, the presented model may reveal stress concentrations induced by the localized loads. An advanced core design to reduce stress concentrations is provided by varying the core strut diameter through the thickness which leads to a graded core. A mass comparison between the homogeneous and the graded core shows that grading the core reduces the core weight by more than 20%. Based on finite element analysis, it can be demonstrated that the present model with a lowered modeling effort well captures the lattice strut stresses of the graded cores, particularly in load application regions.