3D re-entrant Z-shaped structures with negative Poisson’s ratio and compression-twist coupling effect

Abstract Multifunctional mechanical metamaterials can implement multiple mechanical properties, such as both negative Poisson’s ratio (NPR) and compression-twist coupling (CTC) effect, can be applied in complex scenarios in aerospace, biomedical engineering, and other engineering applications. A novel re-entrant Z-shaped (ReZ) structure combining the NPR re-entrant structure and the CTC Z-shaped structure has been proposed. The effects of the geometrical parameters on the equivalent Poisson’s ratio and torsion angle are analyzed by finite element analysis and experiments. The results show that the ReZ structure can exhibit NPR as well as CTC effects by adjusting the geometric parameters. Both NPR and the CTC effect can be tuned over a wide range by modifying the degree of concavity and the height of the unit cell of structure. Finally, two types of enhanced ReZ structures are proposed and discussed. The proposed ReZ structure can enhance the design flexibility and serve as a reference for the design of new multifunctional mechanical metamaterials.