Mechanical properties and energy absorption capacity of a crossed petal-shaped auxetic metamaterial

This paper studies the mechanical performance and energy absorption of a novel crossed petal-shaped two-dimensional metamaterial structure through theoretical analysis, numerical simulation, and experimental validation. The analytical expressions for Poisson’s ratio and elastic modulus are derived. By adjusting the geometric parameters, the Poisson’s ratio changes from positive to zero and then to negative. The elastic modulus values for different parameters are given. Afterwards, numerical simulations are performed by using finite element method and the convergence studies of the simulations are given. The numerical results reach a good agreement with theoretical predictions. The effects of the parameters on the plateau stress and energy absorption are explored, such as open angle, inclined angle, and the lengths of the cell walls. Furthermore, the comparisons with other honeycomb structures are addressed. Finally, experimental studies are conducted to validate the theoretical and numerical results. The obtained results show that the proposed structure has good mechanical properties during deformation, such as double-plateau stress, long plateau stage, and stable deformation behaviors. This research provides valuable insights for the design of new auxetic metamaterials with enhanced energy absorption capability.