Document Type : Research Paper

Authors

Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran.

Abstract

In this paper, a new category of lattice structures called auxetic structures has been studied, which due to low weight, high stiffness and shear strength, have various applications including energy absorption. The unique features of these lattice structures can be related to their special geometry and the Negative Poisson's ratio. In this study, three elastomeric auxetic structures made of TPU with geometries of Anti-tetra chiral, Arrowhead and Reentrant were investigated experimentally at quasi-static and impact loading and compared with a non-auxetic Honeycomb structure. The specimens were fabricated by additive manufacturing method and evaluated using the parameters such as the absorbed energy and the energy per unit length of compaction. Impact loading was performed at two level to investigate the energy absorption capability and deformation mechanisms of the structures in different level of loading. The results show that the auxetic structures absorb much more energy than non-auxetic conventional ones in quasi-static loading and absorb more energy per unit length compaction in impact loading.

Keywords

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