Arc ligament reverse tetrachiral honeycomb structure

Abstract

The invention provides an arc ligament reverse quadrichiral honeycomb structure, which comprises a plurality of cell structures, each cell structure comprises a central pitch circle, the central pitch circle is tangent to four arc ligaments, and the four arc ligaments are rotationally and symmetrically distributed at 90 degrees along the center of the pitch circle; all the cell element structures are arranged on the plane according to the sequence of 4 * 4 pitch circle numbers, so that uniform stress can be ensured when the cell element structures are stressed, and the phenomenon of instability of the area caused by asymmetry is avoided. The curved ligament is introduced into the arc-shaped ligament reverse four-chiral honeycomb structure, so that the stress concentration of a common straight ligament of a chiral honeycomb during stress is broken through, the structure can bear larger force in the compression process, and the energy absorption effect of the structure and the stability of the structure after multiple times of compression are improved.

Description

Technical Field

[0001] This invention relates to the field of chiral honeycomb structures, and more specifically to an arc-shaped ligament reverse tetrachiral honeycomb structure. Background Technology

[0002] As the transportation industry develops towards higher efficiency and safety, automobiles and other vehicles, as well as aerospace transportation equipment, are placing more stringent demands on the stability and energy absorption efficiency of core load-bearing and protective equipment. Against this backdrop, chiral honeycomb, as a typical porous material, demonstrates irreplaceable application potential in aerospace, automotive engineering, and other fields due to its unique deformation mechanism, high specific strength, and excellent energy absorption capacity.

[0003] While chiral honeycomb structures of straight ligaments have become a research hotspot, and can improve total energy absorption by optimizing parameters such as ligament length and thickness, they have revealed key problems in practical applications: under cyclic impact or repeated compressive loading, chiral honeycomb structures of straight ligaments are prone to stress concentration at the midpoint of the ligament, leading to plastic accumulation, which in turn causes a decrease in deformation recovery rate and excessive permanent deformation, severely limiting their applicability in cyclic scenarios. Research has found that the stress concentration problem in traditional chiral honeycomb structures can be artificially controlled by changing the shape of the ligament, effectively improving energy absorption efficiency and recyclability. Summary of the Invention

[0004] To address the existing technical problems, the main objective of this invention is to provide an arc-shaped ligament reverse tetrachiral honeycomb structure to reduce stress concentration during structural deformation and improve the specific energy absorption of the honeycomb structure.

[0005] To achieve the aforementioned technical features, the present invention aims to provide an arcuate ligament anti-tetrachiral honeycomb structure, comprising a plurality of cell structures periodically arranged in the same plane. Each cell structure includes a central segment circle tangent to four arcuate ligaments, which are distributed with 90° rotational symmetry along the center of the segment circle. All cell structures are arranged in a 4×4 sequence on the plane. The arcuate ligaments to the left of the central segment circle are designated as the first arcuate ligament, followed by the second, third, and fourth arcuate ligaments in a clockwise order. The radius of the central segment circle is [missing information]. r The radius of curvature of the arcuate ligament is R The angle between the arcuate ligament and the horizontal line is θ ; The connection between two adjacent cell structures is that they are connected together by arc ligaments with the same number, which ultimately form an arc-shaped ligament reverse tetrachiral honeycomb structure composed of 4×4 cells.

[0006] Preferably, when the honeycomb structure deforms, the central segment circle does not deform, and the first arc ligament, the third arc ligament, the second arc ligament, and the fourth arc ligament undergo relative displacement and rotation, eventually causing the central segment circle to come into complete contact with the arc ligaments.

[0007] Preferably, the arc ligament ends of the cell structure form a square, so that the entire honeycomb structure presents a square shape.

[0008] Preferably, the cross-section of the arcuate ligament is rectangular.

[0009] Preferably, the angle between the arcuate ligament and the horizontal line θ The angle is 67.38°, which allows the arc ligaments between cell structures to meet the tangential condition.

[0010] Preferably, the substrate of the cell structure is selected from TPU-95A, which has superelasticity.

[0011] Preferably, the honeycomb structure is manufactured using 3D printing technology.

[0012] Preferably, the wall thickness of the honeycomb structure is equal.

[0013] The present invention has the following beneficial effects: The honeycomb structure of this invention has high out-of-plane stiffness and can bear greater loads. Compared with traditional inverse tetrachiral honeycombs, the structure of this invention breaks through the limitation of straight ligaments commonly found in chiral honeycombs, and adopts an arc ligament tangential approach to reduce stress concentration during compression. It has strong energy absorption characteristics and stability during continuous out-of-plane compression deformation, realizing the practicality of chiral honeycombs in cyclic use scenarios. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Figure 1 This is a schematic diagram of the arc-shaped ligament reverse tetrachiral honeycomb structure of the present invention.

[0016] Figure 2 This is a schematic diagram of a single cell in the arc-shaped ligament reverse tetrachiral honeycomb structure of the present invention.

[0017] Figure 3 Load-displacement curves of the arc-shaped ligament antiquachiral honeycomb structure and the traditional antiquachiral honeycomb structure using TPU-95A as the substrate.

[0018] Figure 4 The bar chart shows the total absorbed energy of the arcuate ligament anti-tetrachiral honeycomb structure and the traditional anti-tetrachiral honeycomb structure.

[0019] Figure 5The diagram shows the specific energy absorption of the arcuate ligament inverse tetrachiral honeycomb structure and the traditional inverse tetrachiral honeycomb structure.

[0020] In the diagram: central joint circle 1, first arc ligament 2, second arc ligament 3, third arc ligament 4, fourth arc ligament 5. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0025] Example 1: like Figures 1-2 As shown, this invention provides an arcuate ligament reverse tetrachiral honeycomb structure, comprising a plurality of cell structures periodically arranged in the same plane. Each cell structure includes a central segment circle 1, which is tangent to four arcuate ligaments, and the four arcuate ligaments are distributed with 90° rotational symmetry along the center of the segment circle. All cell structures are arranged in a 4×4 sequence on the plane. The ligaments to the left of the central segment circle 1 are the first arcuate ligament 2, followed clockwise as the second arcuate ligament 3, the third arcuate ligament 4, and the fourth arcuate ligament 5. The radius of the central segment circle 1 is... rThe radius of curvature of the arcuate ligament is R The angle between the arcuate ligament and the horizontal line is θ The connection between two adjacent cell structures is that the ligaments with the same number are connected together. For example, the first arc ligament 2 is connected to the first arc ligament 2 of another cell, which ultimately forms an arc-shaped ligament reverse tetrachiral honeycomb structure composed of 4×4 cells.

[0026] Furthermore, the cross-section of the arcuate ligament is rectangular. The substrate of the cell structure is TPU-95A. The honeycomb structure is manufactured using 3D printing technology.

[0027] The theoretical basis of this invention is as follows: ,in EA The total energy absorbed by the honeycomb structure. The effective compressive displacement in a quasi-static compression test.

[0028] ,in m The quality of the honeycomb structure.

[0029] Preferably, in the arc-shaped ligament reverse tetrachiral honeycomb structure, the ends of the arc-shaped ligaments of the cell structure form a square, so that the entire honeycomb structure presents a square shape.

[0030] Furthermore, the aforementioned arc-shaped ligament anti-tetrachiral honeycomb structure is characterized in that: the angle between the arc-shaped ligament and the horizontal line... θ The angle is 67.38°, which is to ensure that the arc ligaments between cell structures can meet the condition of tangency.

[0031] Example 2: See Figure 3 By comparing the arc-shaped ligament inverse quadrichiral honeycomb structure and the traditional inverse quadrichiral honeycomb structure of the same size three times, the effective compression displacements of each structure were determined. Force-displacement curves for two structures were obtained. Figure 3 It is known that the arc-shaped ligament inverse tetrachiral honeycomb structure has better load-bearing capacity and more stable force growth than the traditional inverse tetrachiral honeycomb structure, with the curve slope fluctuation amplitude reduced by about 20% compared to the traditional inverse tetrachiral honeycomb. Notably, this invention can effectively delay the densification process of the traditional chiral honeycomb structure, allowing the material to maintain non-densified elastic deformation over a larger displacement range. Furthermore, combined with... Figure 4The total energy absorption diagram shows that the energy absorption of the arc-shaped ligament reverse quadrichiral honeycomb structure is significantly superior to that of the traditional reverse quadrichiral honeycomb structure. Furthermore, after the second compression, the energy absorption decreased by 22.26%, while the arc-shaped ligament reverse quadrichiral honeycomb structure only decreased by 11.56%. This sufficiently demonstrates that replacing the traditional straight ligament with an arc-shaped ligament not only improves the energy absorption characteristics of the honeycomb structure but also enhances the stability of the chiral honeycomb under cyclic use.

[0032] Example 3: See Figure 5 By calculating the specific energy absorption of the arc-shaped ligament inverse quadrichial honeycomb structure and the traditional inverse quadrichial honeycomb structure using theoretical formulas, it can be accurately concluded that the specific energy absorption of the arc-shaped ligament inverse quadrichial honeycomb structure is 22.5% higher than that of the traditional inverse quadrichial honeycomb structure, and it maintains good stability in the latter two compressions. In contrast, the specific energy absorption of the traditional inverse quadrichial honeycomb structure decreased by more than 20% in the second compression. These data are sufficient to demonstrate that the innovative design of the arc-shaped ligament inverse quadrichial honeycomb structure is feasible and can improve the energy absorption and continuous compression stability of the traditional chiral honeycomb structure.

[0033] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A curved ligament anti-tetrachiral honeycomb structure, characterized in that, It includes several cell structures arranged periodically in the same plane. Each cell structure includes a central segmental circle (1), which is tangent to four arcuate ligaments, which are distributed with 90° rotational symmetry along the center of the segmental circle. All cell structures are arranged in a 4×4 order on the plane. The arcuate ligaments to the left of the central segmental circle (1) are the first arcuate ligament (2), and then, clockwise, the second arcuate ligament (3), the third arcuate ligament (4), and the fourth arcuate ligament (5). The radius of the central segmental circle (1) is... r The radius of curvature of the arcuate ligament is R The angle between the arcuate ligament and the horizontal line is θ ; The connection between two adjacent cell structures is that they are connected together by arc ligaments with the same number, which ultimately form an arc-shaped ligament reverse tetrachiral honeycomb structure composed of 4×4 cells.

2. The arc-shaped ligament antichiral honeycomb structure according to claim 1, characterized in that, When the honeycomb structure deforms, the central segment circle (1) will not deform, and the first arc ligament (2), the third arc ligament (4), the second arc ligament (3), and the fourth arc ligament (5) will undergo relative displacement and rotation, eventually making the central segment circle (1) completely contact the arc ligament.

3. The arc-shaped ligament antichiral honeycomb structure according to claim 1, characterized in that: The arc ligament ends of the cell structure form a square, so that the entire honeycomb structure appears square.

4. The arc-shaped ligament anti-tetrachiral honeycomb structure according to claim 1, characterized in that: The cross-section of the arcuate ligament is rectangular.

5. The arc-shaped ligament anti-tetrachiral honeycomb structure according to claim 1, characterized in that: The angle between the arcuate ligament and the horizontal line θ The angle is 67.38°, which allows the arc ligaments between cell structures to meet the tangential condition.

6. The arc-shaped ligament anti-tetrachiral honeycomb structure according to claim 1, characterized in that: The substrate for the cell structure is TPU-95A, which has superelasticity.

7. The arc-shaped ligament anti-tetrachiral honeycomb structure according to claim 1, characterized in that: The honeycomb structure is manufactured using 3D printing technology.

8. The arc-shaped ligament antichiral honeycomb structure according to claim 1, characterized in that: The wall thickness of the honeycomb structures is equal.

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