Design and Mechanical Properties of Negative Poisson's Ratio Structure-Based Topology Optimization

Scholars have shown significant interest in the design and investigation of mechanical metamaterials with a negative Poisson's ratio as a result of the rapid progress in additive manufacturing technology, giving rise to the concept of metamaterials. The mechanical properties of structures with a negative Poisson's ratio, including Poisson's ratio, elastic modulus, and impact performance, have received growing scrutiny. This paper introduces the design of a novel concave beetle-shaped structure with a negative Poisson's ratio. The structure is developed using the variable density topology optimization method, with the design parameters adjusted to achieve optimal results from six datasets. The mechanical properties of the concave beetle-shaped structure are comprehensively assessed with the integration of mathematical models derived from mechanics theory, quasi-static compression tests, and finite element analyses. This study's findings indicate that the intrinsic parameters of the structure significantly influence its properties. The structure's Poisson's ratio ranges from -0.267 to -0.751, the elastic modulus varies between 1.078 and 5.481 MPa, and the specific energy absorption ranges from 1.873 to 2.634 kJ/kg, demonstrating an improvement of up to 40%.