The Compressive and Shear Characteristics of Miura-ori Forms as Core Materials of Sandwich Structures

The mechanical properties of Miura-ori foldcore metamaterials were studied using finite element simulations. The responses of foldcores with various topological parameters to quasi-static out-of-plane compression and shear loading were analyzed using the relative density as a governing parameter. The non-unique relationships between the core density and the materials' strength in the examined loading directions were revealed, pointing out the strong influence of the Miura-ori topology. Linear relationships were established between the elastic moduli and relative densities of the Miura-ori metamaterials while power law functions of the relative density with different exponent constants were established for the strength in different loading directions. It was shown that the Miura-ori materials possess the highest strength under shear in the X-1 - X-3 plane and it increases with the increase in the relative density. However, this characteristic is strongly influenced by the sector angle a. In general, the difference between the two shear strengths increases when increasing the relative density by using thicker cell walls. It is noted that the strength of the Miura-ori materials as a function of the relative density is nearly constant with respect to the cell dimensions if the values of folding angle ?(0) and sector angle a are given. The mechanical characteristics of the Miura-ori material with equal relative density, which exhibits the highest strength among the analyzed origami models, are compared with the out-of-plane compression and shear responses of prismatic hexagonal honeycomb. It is observed that compression and shear responses of the honeycomb outperform the Miura-ori foldcore in all loading directions when considering large deformations.

Automated summary

The mechanical properties of Miura-ori foldcore metamaterials were investigated using finite element simulations. The study analyzed the response of foldcores with different topological parameters to out-of-plane compression and shear loading, considering relative density as the governing parameter. The results revealed non-unique relationships between core density and material strength in different loading directions, highlighting the significant influence of the Miura-ori topology. Linear relationships were established between elastic moduli and relative densities, while power law functions were established for strength in different loading directions. The study also compared the mechanical characteristics of Miura-ori material with a prismatic hexagonal honeycomb, showing that the honeycomb outperformed the Miura-ori foldcore in all loading directions for large deformations.