Analysis of strut‐based lattice cores in sandwich panels using homogenization and dehomogenization methods

The design freedom provided by additive manufacturing offers new opportunities to fabricate novel structures with a high lightweight potential, such as strut‐based lattice structures. These lattice structures consist of periodically repeated unit cells and can be used in several applications due to their outstanding mechanical performance. One of the possible applications are cores of sandwich panels since the strut‐based lattices offer comparable mechanical properties to conventional honeycomb structures. Moreover, multifunctional use of the sandwich core is enabled by allowing the heat and fluid transfer through the sandwich due to the open‐celled lattice structure. However, strut‐based lattices are rarely utilized as cores in sandwich panels in engineering practice. One of the main reasons for that is the unknown mechanical behavior of lattice cores. In particular, when the sandwich is subjected to concentrated loads, localized stresses and deformations occur in the sandwich core, leading to core damage. In this work, we present a novel analytical model to determine stresses and deformations in the struts of lattice cores of sandwich panels using homogenization and dehomogenization methods. The local core compression caused by localized transverse forces can also be determined by the derived model.