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CN-122014782-A - Double-platform energy-absorbing buffer material with negative poisson ratio characteristic

CN122014782ACN 122014782 ACN122014782 ACN 122014782ACN-122014782-A

Abstract

The invention belongs to the technical field of impact protection and energy absorption, and particularly relates to a double-platform energy absorption buffer material with a negative Poisson ratio characteristic, which comprises a top layer, an energy absorption layer group and a bottom layer which are sequentially and fixedly arranged; the energy absorption layer group consists of a plurality of stacked energy absorption layers, each energy absorption layer comprises a plurality of energy absorption units which are arranged in a rectangular array, each energy absorption unit comprises two energy absorption unit structures which are arranged in an orthogonal mode, each energy absorption unit structure forms a first energy absorption cavity through a connecting surface and a first concave structure, a cross rod is arranged on the outer side of the first concave structure, a second energy absorption cavity is formed by the cross rod and a second concave structure, adjacent energy absorption units in the layers are connected through the cross rod, and each energy absorption layer is fixed through the connecting surface. According to the invention, through various step buckling deformation of the two-stage concave structure, the first and second stress platforms which are generated in sequence in the compression process and are independently adjustable, so that efficient two-stage energy absorption is realized; the three-dimensional structure has the negative poisson ratio effect and the multidirectional bearing capacity, and can effectively avoid transverse expansion under pressure.

Inventors

  • YANG WEIMING
  • YANG FAN
  • LIU HAISHUN
  • ZHANG XIANG
  • ZHAO YUCHENG
  • CHEN PEIJIAN

Assignees

  • 中国矿业大学

Dates

Publication Date
20260512
Application Date
20260310

Claims (10)

  1. 1. The double-platform energy-absorbing buffer material with the negative Poisson ratio characteristic is characterized by comprising a top layer, an energy-absorbing layer group and a bottom layer which are fixedly arranged in sequence; the energy absorption layer comprises a plurality of energy absorption layers which are arranged in a stacked mode, and each energy absorption layer comprises a plurality of energy absorption units which are arranged in a rectangular array mode; The energy absorption unit comprises two energy absorption unit structures which are orthogonally arranged, each energy absorption unit structure comprises a connecting surface which is respectively positioned at the top and the bottom, and the two connecting surfaces are connected through two first concave structures (4) which are symmetrically arranged; The connecting surface and the first concave structure (4) are surrounded to form a first energy absorption cavity; One end of a cross rod (5) is fixed at a concave position of the first concave structure (4), one end of a second concave structure (6) is fixed at the other end of the cross rod (5), the other end of the second concave structure (6) is fixed with one of the connecting surfaces, the cross rod (5) and the second concave structure (6) are both positioned at the outer side of the first energy absorption cavity, and the outer side wall of the first concave structure (4), the second concave structure (6) and the cross rod (5) are surrounded to form a second energy absorption cavity; Two adjacent energy absorption units positioned in the same horizontal plane are fixed through the cross rod (5); The connecting surfaces of the energy absorption units positioned in the same horizontal plane form an installation plane of the energy absorption layer; the installation planes of the adjacent two energy absorption layers are fixed, and the installation plane of the energy absorption layer positioned at the edge is fixed with the corresponding top layer or bottom layer.
  2. 2. The dual platform energy absorbing and cushioning material with negative poisson's ratio characteristics according to claim 1, wherein said first concave structure (4) comprises vertical sections (3) on both upper and lower sides and a first bending section in the middle, wherein the cross section of said first bending section is trapezoidal or triangular.
  3. 3. A dual platform energy absorbing cushioning material having negative poisson's ratio characteristics according to claim 1, wherein said second concave structures (6) are triangular in cross-section.
  4. 4. A dual platform energy absorbing cushioning material having negative poisson's ratio characteristics according to claim 2, wherein a third concave structure (2) is provided in the middle of said interface.
  5. 5. The dual-platform energy absorption buffer material with the negative poisson's ratio characteristic according to claim 4, wherein the third concave structure (2) comprises a horizontal section (1) positioned on the left side and the right side and a second bending section positioned in the middle, wherein the section of the second bending section is trapezoid or triangle, and the horizontal section (1) forms the connecting surface.
  6. 6. A dual platform energy absorbing cushioning material having negative poisson's ratio characteristics according to claim 1, wherein said connecting surface, said first concave structure (4), said second concave structure (6) and said cross-bar (5) are of equal thickness.
  7. 7. The dual-platform energy absorbing and cushioning material with negative poisson's ratio characteristics of claim 1, wherein said energy absorbing element is a semi-crystalline polymeric material.
  8. 8. The dual-platform energy absorbing material with negative poisson's ratio characteristics of claim 5, wherein when the cross sections of the first bending section and the second bending section are both trapezoidal, the shorter side length of the trapezoidal cross section of the first bending section is smaller than the shorter side length of the trapezoidal cross section of the second bending section.
  9. 9. The dual-platform energy absorbing and buffering material with negative poisson's ratio characteristics according to claim 5, wherein when the cross sections of the first bending section and the second bending section are both trapezoidal, the included angle between the oblique side of the trapezoidal cross section of the first bending section and the adjacent vertical section (3) is larger than the included angle between the short side and the oblique side of the trapezoidal cross section of the second bending section.
  10. 10. The dual platform energy absorbing cushioning material of claim 5, wherein said horizontal segment (1) has a length less than the length of the shorter side of the trapezoidal cross section of said second folded segment when the cross section of said second folded segment is trapezoidal.

Description

Double-platform energy-absorbing buffer material with negative poisson ratio characteristic Technical Field The invention belongs to the technical field of impact protection and energy absorption, and particularly relates to a double-platform energy absorption buffer material with a negative poisson ratio characteristic. Background With the rapid development of the fields of new energy automobiles, aerospace, rail transit and the like, higher requirements are put forward on the light weight, high energy absorption efficiency and multistage buffering capacity of the impact protection structure. At present, the traditional energy absorbing elements such as honeycomb structures, foam materials, thin-wall tubes and the like are widely applied to the scenes such as vehicle battery pack bottom protection, aircraft landing buffering and the like. These structures absorb impact energy by plastic deformation or crushing, meeting the protection requirements to some extent. However, with the complexity of the application, conventional energy absorbing structures are increasingly exposed to significant performance shortcomings. The traditional honeycomb or foam material only has a single yield platform, the stress of the platform is fixed, the traditional honeycomb or foam material cannot simultaneously meet the multi-stage energy absorption requirements of low-energy daily impact and high-energy severe impact, and the contradiction of low-energy excessive stiffness and high-energy failure exists. Meanwhile, the positive poisson ratio material generates transverse expansion when being axially pressed, and peripheral cells or connecting pieces are easy to squeeze in a limited space, so that structural instability or shearing damage is induced. The existing negative poisson ratio structure can realize transverse shrinkage, but is mostly in a two-dimensional configuration, is degenerated into a common thin-wall tube in the out-of-plane direction, has insufficient lateral rigidity, is easy to generate Euler buckling or shearing lodging, has uncontrollable deformation mode and obviously reduces energy absorption efficiency. In addition, conventional structures are lower than energy absorption, and it is difficult to achieve high energy absorption under limited space and weight constraints. Accordingly, there is a need for a dual platform energy absorbing and buffering material with negative poisson's ratio characteristics that addresses the above-described problems. Disclosure of Invention It is an object of the present invention to provide a dual platform energy absorbing cushioning material having negative poisson's ratio characteristics to address the above-mentioned problems. In order to achieve the above object, the present invention provides the following solutions: a dual-platform energy-absorbing buffer material with a negative Poisson ratio characteristic comprises a top layer, an energy-absorbing layer group and a bottom layer which are sequentially and fixedly arranged; the energy absorption layer comprises a plurality of energy absorption layers which are arranged in a stacked mode, and each energy absorption layer comprises a plurality of energy absorption units which are arranged in a rectangular array mode; the energy absorption unit comprises two energy absorption unit structures which are orthogonally arranged, each energy absorption unit structure comprises a connecting surface which is respectively positioned at the top and the bottom, and the two connecting surfaces are connected through two first concave structures which are symmetrically arranged; the connecting surface and the first concave structure are surrounded to form a first energy absorption cavity; One end of a cross rod is fixed at a concave position of the first concave structure, one end of a second concave structure is fixed at the other end of the cross rod, the other end of the second concave structure is fixed with one of the connecting surfaces, the cross rod and the second concave structure are both positioned at the outer side of the first energy absorption cavity, and the outer side wall of the first concave structure, the second concave structure and the cross rod are surrounded to form a second energy absorption cavity; two adjacent energy absorbing units positioned in the same horizontal plane are fixed through the cross rod; The connecting surfaces of the energy absorption units positioned in the same horizontal plane form an installation plane of the energy absorption layer; the installation planes of the adjacent two energy absorption layers are fixed, and the installation plane of the energy absorption layer positioned at the edge is fixed with the corresponding top layer or bottom layer. Optionally, the cross section of the second concave structure is triangular. Optionally, the third concave structure includes a horizontal section located at the left and right sides and a second bending section located at the middle, wherei