Elastic Properties and Energy Absorption of Irregular Auxetic Cellular Structure

Based on Euler-Bernoulli beam theory, the equivalent elastic properties of auxetic cellular structure with irregular configurations are derived by using the representative unit cell element approach and multi-step bottom-up approach. Meanwhile, the effect of cell height and inclination angle on the in-plane linear elastic properties is explored. In addition, the Mechanical properties of the auxetic cellular structure with gradient cell height are analyzed under quasi-static compressive loading. The results show that the theoretical derivation results agree well with the results from available literature. The failure of all structures is the layer-by-layer collapse of cellular structural cells. The gradient cell size has little effect on the elastic phase of stress-strain behavior and energy absorption performance. The bidirectional gradient structure has higher platform stress compared with the unidirectional gradient structure. The homogeneous small size structure has the strongest load-bearing capacity as well as energy-absorbing performance. The structure, unidirectional gradient from large to small size, has the weakest load bearing capacity.