Closed-form analysis of the global–local buckling behavior of sandwich columns with additively manufactured lattice cores

Abstract

This study provides a comprehensive analysis of the global (in-plane and out-of-plane) and local (intracell and wrinkling) buckling behavior of sandwich columns with monolithically designed aluminum facesheets and face-centered body-centered cubic (FBCC) lattice cores. Approximate and numerical methods are employed to evaluate the influence of geometric parameters on buckling performance. A novel closed-form, higher-order approach is developed, incorporating core transverse compressibility and a refined displacement field. The finite element method (FEM) is employed to verify the approximate results for sandwich columns under various boundary conditions, using 3D solid elements for the facesheets and beam elements for the lattice core. The results demonstrate strong agreement with the closed-form approximate predictions, capturing both global and local buckling modes while revealing that the boundary conditions significantly affect global buckling but have a rather small influence on the local buckling behavior. The proposed approach offers enhanced accuracy and convergence with numerical methods, providing an efficient framework to analyze wrinkling failure modes in sandwich columns with lattice cores.