Investigation on the Static Response and Failure Process of Metallic Open Lattice Cellular Structures

Abstract: The response of three different cellular core types, suitable for manufacturing crashworthiness sandwich cellular structures, is investigated in this paper. A methodology is developed, comprising linear static and eigenvalue buckling analysis, as well as nonlinear material elastoplastic analysis. The methodology is used to study the structural response and failure process of open lattice metallic cellular cores and derive the most important structural properties of the cellular core, i.e. elasticity modulus, plateau stress and compaction strain. The critical elastoplastic buckling stress of the metallic struts is approximated by analytical solutions, while a simple engineering approach is applied for the estimation of the compaction strain. The influence of core basic design parameters, i.e. strut aspect ratio (radius/length), unit‐cell spatial configuration and unit‐cell size on the structural behaviour is assessed.