Analysis of a novel 3D-printed mechanical metamaterial with tension-induced undulation: Experimental and numerical investigations

Mechanical metamaterials are advanced structures with tailored microarchitectures designed to achieve unique mechanical properties for cutting-edge applications. This study explores a novel metamaterial exhibiting tension-induced undulation by combining additive manufacturing and finite element simulations. Using Fused Deposition Modelling (FDM), test specimens are 3D-printed from polyethylene terephthalate glycol (PETG) and subjected to uniaxial tensile tests to analyse mechanical behaviour, including undulation phenomena, failure mechanisms, and cyclic plasticity. Complementary numerical analyses involve Direct Numerical Simulations (DNS) of unit cell arrays and FE 2 multi-scale modelling to capture macro- and micro-scale interactions. The integration of experimental and numerical approaches provides valuable insights into the potential and challenges of leveraging 3D printing and computational modelling for the efficient design and fabrication of architected metamaterials. The comparison between experimental data and numerical results allows the assessment of the advantages and challenges of integrating 3D printing and modelling options to enhance the design and fabrication processes of architected metamaterials. • A novel 3D metamaterial is 3D-printed and tested experimentally. • It was designed from simulations and has exotic mechanical behaviour. • It is modelled using with Direct Numerical Simulations and Multi-Scale Analysis. • These numerical models are validated against experiments. • Good results are obtained provided that plasticity is considered.