Abstract：When compressed, materials with a negative Poisson's ratio contract laterally, causing the structure to shrink uniformly. This phenomenon involves cooperative deformation across the internal architecture, which sustains a relatively constant and high stress level during the compression process. This mechanism enables exceptionally efficient energy dissipation, making these materials highly resistant to impact. Therefore, employing them as filler material can substantially improve the protective capability of energy-absorbing structures. In this study, the two-dimensional curved concave cells with excellent performance were extended and applied to the filling design of three-dimensional energy-absorbing boxes through the classic and reliable construction method of orthogonal stacking. Based on the proposed two-dimensional curved edge re-entrant negative Poisson's ratio cell, this paper constructs a three-dimensional curved edge re-entrant negative Poisson's ratio cell and designs a negative Poisson's ratio multi-cell filled square hollow structure. The compression deformation failure mode of this energy-absorbing structure was numerically and experimentally studied, and its energy absorption effect was discussed. Research shows that the negative Poisson's ratio multi-cell filled square hollow structure undergoes plastic buckling instability during compression. Its deformation mechanism is mainly manifested as a regular layered fold deformation mode. The generation of each fold corresponds to a specific critical buckling mode, marking the change of the energy absorption process from elastic energy storage to plastic dissipation. The number, formation position and deformation mode of wrinkles in energy-absorbing structures during the collision process are extremely important. During the compression process of the square hollow filled energy-absorbing structure, the energy absorption curve presents a "dual-platform" feature, demonstrating high energy absorption efficiency and stability. The design method and results obtained in this paper provide theoretical basis and technical support for the design of new impact-resistant materials and lightweight energy-absorbing devices, which is conducive to the development and application of lightweight porous negative Poisson's ratio structures with excellent energy absorption performance in the field of vehicle engineering.
2026, Vol. 47 
