Tunable compressive properties of a novel auxetic tubular material with low stress level

摘要

The auxetic tubular materials have attracted wide attention owing to their unusual mechanical properties and potential applications in designing foldable devices. However, most of auxetic tubular structures designed by incorporating re-entrant, chiral or penetrated microstructures remain great challenging in stress concentration because of the presence of shape corners in these structures. In this study, a novel auxetic tubular structure is designed by incorporating the smooth peanut-shaped hole pattern and then is fabricated via 3D printing technique. Subsequently its mechanical properties and deformation characteristics are investigated by uniaxial compression experiments and finite element simulation. Results reveal that the designed tube exhibits significant auxetic performance under compression and the stress level within the structure is significantly reduced, in contrast to the auxetic tubular structure with orthogonal elliptical hole pattern. Finally, the effect of controlling parameters of the designed auxetic tubular structure on Poisson's ratio is studied to better understand its auxetic behavior and also provide tunable design of auxetic tubular structures.