Exploiting nonlinearities through geometric engineering to enhance the auxetic behaviour in re-entrant honeycomb metamaterials

In this section, the effective elastic properties of the 2D and 3D re-entrant type geometries are presented as a function of applied loads. As emphasised in “Numerical methodology”, the members constituting the auxetic microstructure are assumed to be thin strips and circular tubes. This allows the investigation of the influence of non-classical non-linearities. Simulations also reveal, quantitatively, the improvement achieved in auxetic behaviour for the geometries under large deformations.

For the 2D re-entrant geometry, the in-plane Poisson’s ratio, i.e., \({v}_{yx}\) is presented as a…