A Study of Negative Poisson’s Ratio of 3D Printed Auxetic Structures

In this paper, the characteristics of negative Poisson’s ratio with the re-entrant hexagonal honeycomb structures using photocuring 3D printing are studied experimentally. The experimental results are compared with the corresponding linear elastic analytical solutions and finite element simulation results, respectively. The results of the two methods fit well with the experimental results. In the small deformation stage, the behavior of the re-entrant hexagonal honeycomb structures with negative Poisson’s ratio is completely consistent with the analytical and numerical results. However, in the large deformation stage, the curves of experiment with negative Poisson’s ratio gradually deviate from the curves of linear elastic analytical solution and figures are less than the linear elastic analytical solutions, but the characteristic of negative Poisson’s ratio is also stable. The experimental values of Poisson’s ratio in the whole tensile stage are consistent with the numerical solutions. On this basis, we further studied the influence of the rod size and structural thickness on the structural Poisson’s ratio, and found that the thickness of the structures has basically no effect on the Poisson’s ratio, but the values of Poisson’s ratio increase with the increase of the size of the rods.