New Zero Poisson's Ratio Structures

Most materials exhibit positive Poisson's ratio (PR) values, but special structures can also present negative and, even rarer, zero (or close to zero) PR. Null PR structures have received much attention due to their unusual properties and potential applications in different fields, such as aeronautics and bioengineering. Herein, a new and simple near‐zero PR 2D topological model is presented based on a structural block composed of two smooth and rigid bars connected by a soft membrane or spring. It is not based on reentrant or honeycomb‐like configurations, which have been the basis of many null or quasinull PR models. The topological model is 3D printed, and the experimentally obtained PR is −0.003 ± 0.001 which is one of the closest to zero values ever reported. The possibility to extend this model to 3D systems with compression in any direction is discussed. The advantages and disadvantages of these models are also addressed. Null Poisson's Ratio (PR) structures neither contract nor expand under tensile or compressive forces. They have potential applications in fields such as aeronautics and bioengineering. A new zero PR model is proposed based on blocks composed of two rigid bars connected by a soft spring. The model is 3D printed, and the measured PR is −0.003 ± 0.001.