Cushioning Performance of a New Negative Poisson’s Ratio Gradient Structure

Based on the traditional concave hexagonal honeycomb structure，a new type of honeycomb structure with a negative Poisson’s ratio is proposed in combination with the beetle’s sheath wing structure. The impact resistance and energy absorption capacity of the new types of honeycomb structures with negative Poisson’s ratio and the concave hexagonal structure are compared based on the simulation calculation of the finite element software Abaqus/Explicit. The initial impact peak force and energy absorption per unit mass are taken as evaluation indexes. The results show that the initial peak force of the new structure with negative Poisson’s ratio is 28% lower than that of the concave hexagonal structure，and the energy absorption capacity of the structure is increased by 35% before compression enters the densification stage. The cell angle is used as the gradient transformation parameter to construct a new type of negative Poisson’s ratio structure with different gradient arrangements. The cushioning performance of different gradient structures and new uniform types of negative Poisson’s ratio structures are calculated，analyzed，and compared，together with the deformation modes of each structure in the impact process. The results show that the four gradient structures can enhance the impact resistance of the structure，but in terms of energy absorption performance，the layered progressive positive gradient structure （C3） has a strong energy absorption capacity. The experimental samples of the C3 structure and uniform new negative Poisson’s ratio structure are made using 3D printing technology，and the quasi-static impact test is carried out. The correctness of the simulation results is verified through comparative analysis. The research results in this paper show that the reasonable gradient distribution arrangement is of great significance to improve the impact resistance and energy absorption capacity of the structure，and provides a reference for the subsequent exploration of structural buffer design. © 2023 Hunan University. All rights reserved.