Mechanical performance study of high flexibility arrow-shaped concave arc bottoms negative Poisson's ratio honeycomb structure

A novel negative Poisson's ratio honeycomb structure with arrow-shaped concave arc bottoms was presented in this paper. The analytical formulas for the equivalent elastic modulus, equivalent Poisson's ratio, and equivalent density were derived based on the theory of the Timoshenko beam under small static deformations and verified by experiments and finite element simulations. Comparative analysis with common negative Poisson's ratio honeycomb structures revealed that the arrow-shaped concave arc bottom structure exhibits superior deformability under load. Experimental results showed that the elastic modulus of the structure is only 5.34% of that of the classical concave hexagonal structure. Furthermore, a parametric analysis systematically investigated the influence of geometric parameters on the structural in-plane equivalent mechanical properties, which can provide some guidance for the parameter design of the honeycomb structure in practical application.