Mechanical characterization of a metamaterial with negative Poisson’s ratio under compressive loading: Experimental along with FEM
Ren Shunshun, Guo Zhao
Abstract
A novel mechanical metamaterial with a negative Poisson’s ratio was successfully designed and fabricated using digital light processing (DLP). To evaluate its mechanical properties and auxetic behavior, both experimental compression tests and finite element simulations were performed. The deformation behavior of the metamaterial was simulated in two directions using Abaqus software. The results demonstrate that the metamaterial exhibits a pronounced auxetic response, characterized by lateral contraction when subjected to compressive loading. This exceptional auxetic behavior was achieved solely through the incorporation of oval-shaped gaps in the design. When the structure was compressed along the y-direction, stress distribution analysis identified stress concentrations at the corners of the gaps, particularly along the x-direction, where the maximum stress reached approximately 60 MPa. Similarly, the strain distribution followed the stress pattern, with a maximum strain of 0.05 observed in the same regions. Displacement contour analysis further revealed that the most significant displacement occurred within the oval-shaped gaps near the left and right sides of the structure. Moreover, the auxetic behavior of the designed structure was found to be direction-dependent. When subjected to loading perpendicular to the auxetic direction, the structure exhibited non-uniform deformation, accompanied by sliding between its upper and lower sections. Finally, with an energy absorption capacity of 15.91 MJ, the designed metamaterial demonstrates outstanding mechanical performance, making it a promising candidate for energy-absorbing applications.