A novel square-section auxetic lattice tubular metamaterial with favourable bending behavior

Abstract

Abstract The bending properties of square auxetic tubular lattice (SATL) metamaterial were examined, in comparison with the circular auxetic tubular lattice (CATL) metamaterials and square diamond tubular lattice (SDTL) structures. The SATL metamaterial possesses higher flexibility compared with SDTL, and stronger collision resistance than the CATL. The influences of curvature radius R and unit cell rib width d on the bending properties of the SATL metamaterials were analyzed. The results show that smaller R and d could make the SATL metamaterials more flexible. Then, the bending properties of SATL metamaterials were calculated and analyzed with respect to changes of wall thickness T . The results show that a larger T results in better crashworthiness and higher flexibility of the overall structure. In, addition, an enhanced SATL (ESATL) was proposed and studied to obtain enhanced flexibility. Eventually, in order to further demonstrate the advantages of the SATL metamaterials, its mechanical properties under bending loads were compared with those of the square tubular full structures. Taking into account their attractive bending behavior, the SATL metamaterials show significant potential for use in soft robotics, aerospace, and protective engineering applications.