Artificially structured materials, also called metamaterials, can achieve very unique properties due to the fact that their attributes are mainly derived from the design of the structures. This work gives an overview of the mechanical behavior of four differently designed and 3D-printed metamaterial structures.For each structure, both, the printing technique and the materials used for printing were varied. In total four different polymers were investigated and processed with three different 3D-printing techniques. Their mechanical behavior was studied by compression tests, which showed the wide range of material properties that can be achieved by utilizing the different materials/3D-printing techniques. In addition, bending tests of 3D-printed bending specimens were conducted to provide material data for subsequent finite element simulation of the structures. The comparison of experiments and numerical simulations gave further insight into local deformation mechanisms and allowed for a better understanding of the overall deformation behavior.

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Mechanical metamaterials with zero or negative Poisson’s ratio were subject to increasing research interest over the last few years. Their energy absorption capabilities make them suitable for impact and dampening applications, such as personal protection equipment or packaging materials. The variable porosity and unusual mechanical properties also make them applicable in drug delivery systems and wound management. Herein, we present an extension to common auxetic structures, including tetra-chirals and tetra-antichirals. By introducing an asymmetry in the design of their unit cell, Poisson’s ratio can be varied over a broad range. Specimens with a selected amount of asymmetry were additively manufactured with a thermoplastic polyurethane using fused filament fabrication. Compression tests were performed to investigate the influence of the asymmetry on Poisson’s ratio and the compression modulus. Two different numerical models were employed using ABAQUS to describe the mechanical properties of the structures and were verified by the experiments. The numerical models are based on three-point bending test data. Both asymmetric designs show an influence of the asymmetry onto Poisson’s ratio, resulting in variable Poisson’s ratio, porosity, and compression modulus.