A Novel Three‐Dimensional Star Structure with Stable Negative Poisson's Ratio

The concave star structure is a typical negative Poisson's ratio structure which reduces the volume of the structure through mechanical compression. Usually, the parameters of the structure such as wall thickness, bevel angle, and size affect the strength, stiffness, and energy absorption characteristics of the structure. This study designs a novel 3D star‐shaped structure with a negative Poisson's ratio. Through finite element method simulation and mechanical experiments, the influence of relevant parameters on the strength, stiffness, and Poisson's ratio of the overall structure is explored, and the deformation mode, load‐bearing capacity, and energy absorption capacity of the structure under quasistatic compression conditions are systematically studied, and structural parameters with good mechanical properties are finally obtained. The unit cell of the proposed structure has higher strength and specific energy absorption, and the proposed star‐shaped structure shows a stable negative Poisson's ratio phenomenon after array combination compared with the traditional star‐shaped structure. The structure designed in this research has both high strength and stiffness, as well as good buffering and high energy‐absorbing potential, to prevent structural fracture under limited compression distance, which may have broad application prospects in the field of protective structures.