Quasi-static large deformation compressive behaviour of origami-based metamaterials

摘要

An analytical model of the quasi-static response of Miura-ori based metamaterial to in-plane compression was first developed to describe the major mechanical characteristics related to the strength and energy absorption capacity of this material in the analysed loading direction. It is assumed that the base material is ductile and can be approximated as a perfectly plastic material. The results revealed that the initial strength and densification strain of the Miura-ori based metamaterial cannot be uniquely defined by its relative density, in contrast to most conventional cellular materials used for energy absorption applications. A particular value of the initial folding angle gamma(0) corresponds to the minimum relative density for each static sector angle alpha. This value determines the transition point separating the region where the initial material strength increases with the increase of the relative density from the one where this strength decreases with the increase of the relative density. Miura-ori based metamaterials with large initial dihedral angle gamma(0) have larger energy absorption capacity per unit mass, however exhibiting significant variations of Poisson's ratios during compression. The energy absorption efficiency of the Miura-ori based metamaterials was compared with that of single-walled regular honeycombs under in-plane compression. It is demonstrated that, for certain combination of the geometric parameters a, b, alpha and gamma(0), the origami-based materials can outperform the honeycombs with the same relative density. The analytical model was verified by the numerical simulations of the response of single cells with various geometries and multi sheet origami configurations. The model predictions were also validated by a quasi-static compression test of a four-sheet origami specimen.