A concave chiral cell with high impact resistance and its honeycomb structure

Abstract

The present invention discloses a concave chiral cell with high impact resistance, comprising: a concave hexagonal structure, the concave hexagonal structure includes two horizontal cell walls and two groups of inclined cell wall groups arranged between the two ends of the two horizontal cell walls, each group of inclined cell wall groups includes two inclined cell walls, one end of the two inclined cell walls is respectively connected to the end of one side of the two horizontal cell walls, and the other ends of the two inclined cell walls are folded inwards towards the inside of the concave hexagonal structure to form an inflection point; a circular ring component arranged inside the concave hexagonal structure, the two first extension arms are respectively horizontally tangent to the upper and lower ends of the chiral circular ring component. At the same time, a honeycomb structure using the above concave chiral cell is also provided. Compared with the traditional concave honeycomb, the present invention has better deformation stability, impact resistance characteristics, and higher bearing capacity and elastic modulus.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical metamaterials, and particularly relates to a concave chiral cell with high impact resistance and its honeycomb structure. Background Art

[0002] The negative Poisson's ratio honeycomb structure has a unique geometric design. When subjected to force, its internal structure will expand laterally instead of contracting, thereby effectively dispersing and absorbing external impact energy, and significantly improving the impact resistance and energy absorption capacity of the structure. This characteristic makes it have broad application prospects in the manufacture of high-performance protective equipment, such as helmets, bulletproof vests, etc. In addition, such structures also perform well in the fields of national defense, aerospace, shipbuilding, etc., and can better protect the safety of personnel and property.

[0003] So far, various negative Poisson's ratio structures have been designed, including concave structures, rotating polygon structures, chiral structures, perforated plate structures, staggered polygon structures, and so on. Among them, the concave structure and the chiral structure are the most classic negative Poisson's ratio structures, with characteristics such as high programmability and impact resistance. However, in their actual engineering applications, the concave and chiral honeycomb structures often have disadvantages such as low elastic modulus, insufficient load-bearing capacity, and unstable deformation mode, which greatly limit their application scope. Therefore, improving the deformation stability, load-bearing capacity, and impact resistance of the honeycomb structure, while maintaining its negative Poisson's ratio characteristics to a certain extent, is the research focus and main challenge in the field of impact resistance of negative Poisson's ratio structures. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects in the prior art, and provide a concave chiral cell with high impact resistance and its honeycomb structure, which has better deformation stability, impact resistance characteristics, higher load-bearing capacity, and elastic modulus compared with traditional concave honeycombs.

[0005] To achieve the above purpose, the present invention provides a concave chiral cell with high impact resistance, including:

[0006] A concave hexagonal structure, the concave hexagonal structure includes two horizontal cell walls and two groups of inclined cell wall groups arranged between the two ends of the two horizontal cell walls. Each group of inclined cell wall groups includes two inclined cell walls. One end of the two inclined cell walls is respectively connected to the end of one side of the two horizontal cell walls, and the other end of the two inclined cell walls is folded inward and connected to form an inflection point inside the concave hexagonal structure;

[0007] A circular ring component disposed within the concave hexagonal structure. The circular ring component includes a chiral circular ring member and two first extension arms. The center of the chiral circular ring member coincides with the midpoint of the line connecting the center points of the two horizontal cell walls. The two first extension arms are respectively horizontally and tangentially connected to the upper and lower ends of the chiral circular ring member. The other ends of the two first extension arms away from the chiral circular ring member extend in opposite directions and are respectively connected to the inflection points of two sets of inclined cell wall groups.

[0008] Further, the sum of the horizontal projection length of the inclined cell wall and the length of the first extension arm is equal to half of the length of the horizontal cell wall. This can control the connection angle between the inclined cell wall and the horizontal cell wall, enabling the overall structure to have better deformation stability, impact resistance characteristics, as well as higher load-bearing capacity and elastic modulus.

[0009] Further, the radius of the chiral circular ring member is 1 mm - 6.5 mm. Within this range, the impact resistance characteristics of the novel honeycomb structure can be enhanced.

[0010] Further, the wall thicknesses of the horizontal cell wall, inclined cell wall, chiral circular ring member, and first extension arm are all 2 mm - 5 mm. Within this range, the impact resistance characteristics of the novel honeycomb structure can be enhanced.

[0011] A honeycomb structure is composed of the above-mentioned high-impact-resistant concave chiral cells arranged and combined.

[0012] Further, the honeycomb structure is arranged in several columns in the transverse direction and several rows in the longitudinal direction. Among them, in each column, two adjacent concave chiral cells share a horizontal cell wall for arrangement and combination. In each row, two adjacent concave chiral cells are connected by a first connecting member, and the first connecting member connects the inflection points of two adjacent concave chiral cells for arrangement and combination.

[0013] Further, in each row, the setting directions of two adjacent concave chiral cells are the same, and the first connecting member is an inclined connecting arm.

[0014] Further, in each row, there is a height difference between the positions of two adjacent concave chiral cells, and the size of the height difference is equal to the diameter of the chiral circular ring member.

[0015] Further, it further includes a second connecting member, and the second connecting member is a circular ring body connecting arm.

[0016] Further, in each row, two adjacent concave chiral cells are arranged in a mirror-symmetrical manner, and the first connecting member is a straight connecting arm or a circular ring body connecting arm.

[0017] Compared with the prior art, the present invention has the following advantages: When the cell is subjected to external pressure, its inclined cell wall rotates inward. During the rotation of the inclined cell wall, the chiral circular ring member inside it provides a supporting effect on the inclined cell wall. During the deformation process, the chiral circular ring member rotates, guiding the inclined cell wall to bend and deform. This deformation mechanism greatly improves the elastic modulus, load-bearing capacity, impact resistance characteristics, and deformation stability of the novel concave chiral honeycomb. Compared with the traditional concave honeycomb structure, the novel concave chiral honeycomb has better deformation stability and uniformity; the proposed concave chiral honeycomb has better impact resistance characteristics; through structural optimization design, it is obtained that reducing the radius of the chiral component circular ring within a certain range can increase the impact resistance characteristics of the novel honeycomb structure; it is obtained that increasing the cell wall thickness within a certain range can increase the impact resistance characteristics of the novel honeycomb structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 is a schematic structural diagram of a concave chiral cell with high impact resistance of the present invention;

[0020] Figure 2 is a schematic structural diagram of three first connectors of the present invention;

[0021] Figure 3 is a schematic structural diagram of the honeycomb structure of Embodiment 1 of the present invention;

[0022] Figure 4 is a schematic structural diagram of the honeycomb structure of Embodiment 2 of the present invention;

[0023] Figure 5 is a schematic structural diagram of the honeycomb structure of Embodiment 3 of the present invention;

[0024] Figure 6 is a schematic structural diagram of the honeycomb structure of Embodiment 4 of the present invention;

[0025] Figure 7 is a schematic structural diagram of the honeycomb structure of Comparative Example 1 of the present invention;

[0026] Figure 8 is a schematic diagram of the size markings of the concave chiral cell of the present invention;

[0027] Figure 9 is a schematic diagram of the size markings of the concave chiral cell of the present invention;

[0028] Figure 10 are the static experiment and finite element stress-strain curve diagrams of the comparative example and Example 4 of the present invention;

[0029] Figure 11 are the quasi-static experiment and finite element simulation deformation mode comparison diagrams of the comparative example and Example 4 of the present invention;

[0030] Figure 12 is the specific energy absorption (SEA) and average stress comparison diagram of the present invention;

[0031] Figure 13 is the comparison diagram of the influence of the radius of the chiral circular ring part of the present invention on the anti-impact characteristics;

[0032] Figure 14 is the comparison diagram of the influence of different radii of the chiral circular ring part of the present invention on the maximum dynamic negative Poisson's ratio;

[0033] Figure 15 is the comparison diagram of the influence of different cell wall thicknesses of the present invention on the anti-impact characteristics;

[0034] Figure 16 is the comparison diagram of the influence of the impact velocity on the anti-impact characteristics of the present invention;

[0035] Figure 17 is the comparison diagram of the influence of the impact direction on the anti-impact characteristics of the present invention;

[0036] Figure 18 is Figure 10 the corresponding color diagram;

[0037] Figure 19 is Figure 12 the corresponding color diagram;

[0038] Figure 20 is Figure 13 the corresponding color diagram;

[0039] Figure 21 is Figure 14 the corresponding color diagram;

[0040] Figure 22 is Figure 15 the corresponding color diagram;

[0041] Figure 23 is Figure 16 the corresponding color diagram;

[0042] Figure 24 is Figure 17 the corresponding color diagram.

[0043] In the figure, it includes:

[0044] 1. Concave hexagonal structure; 11. Horizontal cell wall; 12. Tilted cell wall group; 121. Tilted cell wall; 2. Ring component; 21. Chiral ring element; 22. First extension arm; 3. Inner folding point; 4. First connecting piece; 5. Second connecting piece. Detailed implementation mode

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are one embodiment of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present invention.

[0046] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0047] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features.

[0048] Please refer to Figure 1 , the embodiments of the present invention provide a concave chiral cell with high impact resistance, including:

[0049] As Figure 1 shown, the concave chiral cell of this embodiment includes a concave hexagonal structure 1 and a ring component 2 disposed inside the concave hexagonal structure 1. The concave hexagonal structure 1 includes two horizontal cell walls 11 and two groups of tilted cell wall groups 12 disposed between the two ends of the two horizontal cell walls 11. Each group of tilted cell wall groups 12 includes two tilted cell walls 121. One ends of the two tilted cell walls 121 are respectively connected to the ends on one side of the two horizontal cell walls 11, and the other ends of the two tilted cell walls 121 are folded inwardly and connected to form an inner folding point 3 inside the concave hexagonal structure 1. In this way, two inner-folded tilted cell wall groups 12 as shown in Figure 2 are formed at both ends of the two horizontal cell walls 11;

[0050] The circular ring component 2 includes a chiral circular ring member 21 and two first extension arms 22. The center of the chiral circular ring member 21 coincides with the midpoint of the line connecting the center points of the two horizontal cell walls 11. The two first extension arms 22 are arranged parallel to the above-mentioned horizontal cell walls 11, and the two first extension arms 22 are respectively horizontally and tangentially connected to the upper and lower ends of the chiral circular ring member 21. The extension directions of the other ends of the two first extension arms 22 away from the chiral circular ring member 21 are opposite to each other and are respectively connected to the inner folding points 3 of the two groups of inclined cell wall groups 12. Since the two first extension arms 22 are respectively installed on the upper and lower sides of the chiral circular ring member 21, after determining the positions of the chiral circular ring member 21 and the first extension arms 22 during production, then connect the inclined cell wall 121 to the first extension arm 22. At this time, the inclined cell wall group 12 consists of a long inclined cell wall 121 and a short inclined cell wall group 12. The entire concave chiral cell is centrosymmetric with the center of the chiral circular ring member 21 as the reference point. In order to ensure the consistency of the structure, the sum of the horizontal projection length of the inclined cell wall 121 and the length of the first extension arm 22 in this embodiment is equal to half of the length of the horizontal cell wall 11.

[0051] In this embodiment, reducing the radius of the chiral circular ring member 21 to a certain extent can enhance the impact resistance of the concave chiral honeycomb. Through the impact resistance test, it can be known that the radius of the chiral circular ring member 21 is optimal within the range of 1 mm - 6.5 mm. Therefore, different radii of the chiral circular ring member 21 can be selected according to the cost and actual requirements. The radius of the chiral circular ring member 21 can be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm or 6.5 mm.

[0052] Furthermore, the wall thicknesses of the horizontal cell wall 11, the inclined cell wall, the chiral circular ring member 21 and the first extension arm 22 in this embodiment are the same. In order to achieve the best effect, the wall thicknesses of the above components are controlled within the range of 2 mm - 5 mm. The wall thickness can be selected according to actual requirements. For example, the wall thicknesses of the above components can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm.

[0053] Embodiment 1

[0054] Such as Figure 2 and Figure 3The present invention also provides a honeycomb structure, which is formed by arranging and combining the above-mentioned high-impact-resistant concave chiral cells. Among them, the honeycomb structure arranges several columns in the horizontal direction and several rows in the vertical direction; in each column, two adjacent concave chiral cells share a horizontal cell wall 11 for arranging and combining; in each row, two adjacent concave chiral cells are arranged in a mirror-symmetrical manner and are connected by a provided first connecting member 4. The first connecting member 4 connects the inner folding points 3 of two adjacent concave chiral cells for arranging and combining. In this embodiment, the first connecting member 4 is a straight connecting arm, and the length of the straight connecting arm is the same as the length of the horizontal cell wall 11.

[0055] Embodiment 2

[0056] As Figure 2 and Figure 4 The present invention also provides a honeycomb structure, which is formed by arranging and combining the above-mentioned high-impact-resistant concave chiral cells. Among them, the honeycomb structure arranges several columns in the horizontal direction and several rows in the vertical direction; in each column, two adjacent concave chiral cells share a horizontal cell wall 11 for arranging and combining; in each row, the arrangement directions of two adjacent concave chiral cells are the same, and they are connected by a provided first connecting member 4. The first connecting member 4 connects the inner folding points 3 of two adjacent concave chiral cells for arranging and combining. In this embodiment, the first connecting member 4 is an inclined connecting arm, and the horizontal projection length of the inclined connecting arm is the same as the length of the horizontal cell wall 11.

[0057] Embodiment 3

[0058] As Figure 2 and Figure 5 The present invention also provides a honeycomb structure, which is formed by arranging and combining the above-mentioned high-impact-resistant concave chiral cells. Among them, the honeycomb structure arranges several columns in the horizontal direction and several rows in the vertical direction; in each column, two adjacent concave chiral cells share a horizontal cell wall 11 for arranging and combining; in each row, two adjacent concave chiral cells are arranged in a mirror-symmetrical manner and are connected by a provided first connecting member 4. The first connecting member 4 connects the inner folding points 3 of two adjacent concave chiral cells for arranging and combining. In this embodiment, the first connecting member 4 is a toroidal connecting arm, the structure of the toroidal connecting arm is the same as the structure of the chiral toroid 21, and the radius of the toroidal connecting arm is the same as the radius of the chiral toroid 21. The horizontal projection length of the toroidal connecting arm is the same as the length of the horizontal cell wall 11.

[0059] Embodiment 4

[0060] As Figure 2 and Figure 6The present invention also provides a honeycomb structure, which is formed by arranging and combining the above-mentioned high-impact-resistant concave chiral cells. Among them, the honeycomb structure arranges several columns in the horizontal direction and several rows in the vertical direction; in each column, two adjacent concave chiral cells share a horizontal cell wall 11 for arrangement and combination; in each row, the setting directions of two adjacent concave chiral cells are the same, and they are connected by a first connecting member 4 provided. The first connecting member 4 connects the inner folding points 3 of two adjacent concave chiral cells for arrangement and combination. The above-mentioned first connecting member 4 is a straight connecting arm. There is a height difference between the positions of two adjacent concave chiral cells, and the size of the height difference is equal to the diameter of the chiral ring member. It also includes a second connecting member 5. The horizontal cell walls 11 of two adjacent concave chiral cells in each row are connected by the second connecting member 5. The second connecting member 5 is a toroidal connecting arm. The length of the above-mentioned straight connecting arm and the horizontal projection length of the toroidal connecting arm are both the same as the length of the horizontal cell wall 11, and the radius of the toroidal connecting arm is the same as the radius of the chiral ring member 21. The horizontal projection length of the toroidal connecting arm is the same as the length of the horizontal cell wall 11. In particular, due to the height difference formed by adjacent concave chiral cells in each row, in order to make the second concave chiral cell as neat as the first concave chiral cell, an additional second connecting member 5 can be provided in the second concave chiral cell for filling.

[0061] Comparative example

[0062] As Figure 7 shown, the honeycomb structure of this comparative example includes a conventional concave hexagonal structure 1 cell. The cells in each row are connected by a straight connecting arm, and the cells in each column share the horizontal cell wall 11.

[0063] In summary Figures 3 - 6 shows four honeycomb structures composed of the concave chiral cells of the present invention and different connecting members, which are represented by RCH-1, RCH-2, RCH-3, and RCH-4 for the honeycomb structures of Examples 1-4, and TRH represents Figure 7 the honeycomb structure of the comparative example. As Figure 8 shown, the length of the two horizontal cell walls 11 is l, the height between the two horizontal cell walls 11 is h, the vertical height from the connection point of the inner folding point 3 of the long inclined cell wall 121 to the upper horizontal cell wall 11 is h1, the height from the connection point of the inner folding point 3 of the short inclined cell wall 121 to the lower horizontal cell wall 11 is h2, and the ring radius of the chiral ring member and the toroidal connecting arm is r. The wall thickness of the horizontal cell wall 11 and the inclined cell wall 121 is t, the included angle between the long inclined cell wall 121 and the horizontal cell wall 11 is α, and the included angle between the short inclined cell wall 121 and the horizontal cell wall 11 is β;

[0064] Relative density is an important parameter to describe the physical properties of porous materials and reflect the proportion of pores. Take a representative concave chiral cell in RCH-1 to calculate the relative density. AsFigure 8 As shown. Since two adjacent unit cells share a cell wall, the actual cell wall area of a representative concave chiral unit cell can be obtained by the following formula:

[0065] (1)、A w =A h +A I +2πrt

[0066] Where AI and Ah are the areas of the inclined cell wall 121 and the horizontal cell wall 11 respectively, and are defined as and

[0067] A h =t[2l + l - (h + 2r)cotα], and the third term r on the right side of formula (1) is the area of the circular ring in the internal chiral circular ring part.

[0068] According to the geometric relationship, the area of the representative unit is:

[0069] (2)、A u =2lh - h(h + 2r)cotα

[0070] According to the area relationship, substituting formula (1) and formula (2) into the relative density of RCH-1 can be directly obtained:

[0071]

[0072] Based on the above calculation formula, similarly, the calculation methods of the relative densities of RCH-2, RCH-3, and RCH-4 are the same as that of RCH-1. Only the results are given here, and they are respectively:

[0073] (3)、

[0074] (4)、

[0075] (5)、

[0076] Taking RCH-4 as an example, when the concave chiral unit cell is compressed in the y direction as shown in Figure 9 , its inclined cell wall 121 will rotate towards the inside of the cell. During the rotation of the inclined cell wall 121, the internal chiral component will provide a supporting effect on the inclined cell wall 121. During the deformation process, the chiral component will rotate, guiding the inclined cell wall 121 to bend and deform. This deformation mechanism greatly improves the elastic modulus, load-bearing capacity, impact resistance, and deformation stability of the novel concave chiral honeycomb. Through the Figure X theoretical model shown and the following formula to calculate the dynamic Poisson's ratio effect of the honeycomb structure:

[0077] (6)、

[0078] (7)、 where v d and Δy are the dynamic Poisson's ratio and the vertical displacement, is the average displacement of the entire structure in the x-direction, L pri and L pli are the displacements of the pri and pli points in the x-direction, and n is the number of single-sided points for calculating the Poisson's ratio.

[0079] The specific energy absorption (SEA) is an important indicator reflecting the impact resistance of the structure and can be calculated by the following formula:

[0080] (8)、 In the formula, ρ* and ρ are the relative density of the honeycomb structure and the mass density of the base material, and εd is the densification strain of the structure.

[0081] Figure 10 and Figure 11 respectively give the stress-strain curves and deformation modes of the TRH and RCH-4 of the comparative example under experimental and finite element quasi-static compression. Among them Figure 10 "Exp" in it is experimental data, and "F.E." is finite element simulation data, Figure 11 in (a) is the deformation simulation diagram of TRH, and (b) is the deformation simulation diagram of RCH-4D. It can be seen that the elastic modulus and platform stress of RCH-4 have been greatly improved compared with the traditional honeycomb structure, and the deformation mode of RCH-4 is also more uniform and stable compared with the concave honeycomb.

[0082] Next, under the premise that the wall thickness of each component is the same and the radius of the chiral circular ring is the same, an impact load test is carried out. Specifically, the wall thickness of TRH, RCH-1, RCH-2, RCH-3 and RCH-4 is 3 mm, and the chiral circular ring radius of RCH-1, RCH-2, RCH-3 and RCH-4 is 4.5 mm. Figure 12 shows the comparison diagram of the specific energy absorption and the average stress of each honeycomb structure under the same impact load, and the specific values are shown in Table (1) below:

[0083]

[0084] Table (1) Comparison diagram of specific energy absorption and average stress

[0085] As can be seen from Table (1), the specific energy absorption of RCH-1, RCH-2, RCH-3, and RCH-4 is increased by 55%, 57%, 63%, and 87% respectively compared to the traditional concave honeycomb TRH. In addition, the proposed concave chiral honeycomb exhibits a higher nominal average stress than the traditional concave honeycomb. The plateau stresses of RCH-1, RCH-2, RCH-3, and RCH-4 are approximately 2.07 times, 1.97 times, 2.27 times, and 3 times that of the traditional concave honeycomb. This indicates that the newly proposed honeycomb structure has greater advantages than the traditional concave honeycomb in terms of impact energy absorption and load-bearing capacity.

[0086] As Figure 13 and Figure 14 , RCH-1, RCH-2, RCH-3, and RCH-4 demonstrate the influence of different chiral circular ring radii on the impact resistance characteristics and maximum dynamic Poisson's ratio effect of the concave chiral honeycomb on the premise of the same wall thickness. Specifically, the wall thicknesses of RCH-1, RCH-2, RCH-3, and RCH-4 are 3 mm, and the specific values are shown in the following Table (2) and Table (3):

[0087] SEA (J / G) RCH - 1 RCH - 2 RCH - 3 RCH - 4 r = 3.5 mm 3.0413 3.3351 2.9407 3.9809 r = 4.5 mm 2.4954 2.5350 2.6405 3.0177 r = 5.5 mm 2.4269 2.1134 2.0395 2.4899 r = 6.5 mm 2.1642 1.9568 1.8059 2.2163

[0088] Table (2) Influence of Chiral Circular Ring Radius on Impact Resistance Characteristics

[0089]

[0090] Table (3) Influence of Chiral Circular Ring Radius on Maximum Dynamic Negative Poisson's Ratio

[0091] As can be seen from Table (2), reducing the radius of the chiral circular ring 21 to a certain extent can enhance the impact resistance characteristics of the concave chiral honeycomb; as can be seen from Table (3), with the increase of the radius of the chiral circular ring 21, the influence on the maximum dynamic Poisson's ratio of the honeycomb structure of the present invention is not significant. The increase in the radius of the chiral circular ring 21 will cause the maximum dynamic Poisson's ratio of RCH-2 and RCH-4 to show an increasing trend while the maximum dynamic Poisson's ratio of RCH-3 shows a decreasing trend.

[0092] As Figure 15 , RCH-1, RCH-2, RCH-3, and RCH-4 demonstrate the influence of different cell wall thicknesses on the impact resistance characteristics of the honeycomb structure on the premise that the radii of the chiral circular rings are the same. Specifically, the radii of the chiral circular rings of RCH-1, RCH-2, RCH-3, and RCH-4 are 4.5 mm, and the specific values are shown in Table (4):

[0093] SEA (J / G) TRH RCH - 1 RCH - 2 RCH - 3 RCH - 4 t = 2 mm 1.14608 1.88249 1.4410 1.55111 1.94292 t = 3 mm 1.87858 2.49545 2.5350 2.64045 3.01768 t = 4 mm 2.15244 3.90230 3.2011 3.53073 4.13616 t = 5 mm 3.33137 4.56772 4.0420 4.21236 4.41568

[0094] Table (4) Influence of Cell Wall Thickness on Impact Resistance Characteristics It can be known from Table (4) that appropriately increasing the cell wall thickness can effectively improve the impact resistance characteristics of the honeycomb structure.

[0095] The following is to conduct impact tests at different impact speeds and in different directions on the premise that the wall thickness of each component is the same and the radius of the chiral circular ring is the same. Specifically, the wall thicknesses of TRH, RCH-1, RCH-2, RCH-3, and RCH-4 are 3 mm, and the chiral circular ring radii of RCH-1, RCH-2, RCH-3, and RCH-4 are 4.5 mm. As Figure 16 and Figure 17 shown in the specific energy absorption comparison diagrams of the honeycomb structure at different impact speeds and in different impact directions. The specific values are shown in Table (5) and Table (6):

[0096] SEA (J / G) TRH RCH - 1 RCH - 2 RCH - 3 RCH - 4 10 m / s 1.615 2.495 2.495 2.640 3.018 50 m / s 3.201 4.851 5.570 4.613 5.714 100 m / s 9.103 11.837 13.20 13.136 13.251

[0097] Table (5) Influence of impact speed on anti-impact characteristics

[0098]

[0099]

[0100] Table (6) Influence of impact direction on anti-impact characteristics

[0101] It can be observed from Table (5) that as the impact speed increases, the specific energy absorption of each honeycomb increases significantly. This is because the increase in the inertial effect leads to an increase in the platform stress. In addition, it can be observed that at different impact speeds, the specific energy absorption (SEA) of the newly proposed honeycomb structure is higher than that of the traditional concave honeycomb structure. It can be seen from Table (6) that under vertical impact, the specific energy absorption of RCH-1, RCH-2, RCH-3, and RCH-4 is increased by 55%, 58%, 63%, and 87% respectively compared with the traditional concave structure. For lateral impact, compared with the traditional concave honeycomb, the specific energy absorption of the four newly proposed honeycomb structures is increased by 116%, 138%, 18%, and 122% respectively. It can be seen that RCH-4 has excellent energy absorption characteristics under vertical impact, while RCH-2 has the maximum anti-impact characteristics under lateral impact.

[0102] In summary, compared with the traditional concave honeycomb structure, the honeycomb structure of the present invention has better deformation stability and uniformity; has better anti-impact characteristics; through structural optimization design, it is obtained that reducing the radius of the chiral circular ring within a certain range can increase the anti-impact characteristics of the new honeycomb structure; increasing the cell wall thickness within a certain range can increase the anti-impact characteristics of the new honeycomb structure.

[0103] The above is only the preferred embodiment of the present invention and is not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A highly impact-resistant concave chiral cell, characterized in that: include: An inward-concave hexagonal structure (1), the inward-concave hexagonal structure (1) comprising two horizontal cell walls (11) and two groups of inclined cell wall groups (12) arranged between the two ends of the two horizontal cell walls (11), each group of inclined cell wall groups (12) comprising two inclined cell walls (121), one end of the two inclined cell walls (121) being respectively connected to the end of one side of the two horizontal cell walls (11), and the other ends of the two inclined cell walls (121) being folded inwardly toward the inside of the inward-concave hexagonal structure (1) to form an inner folding point (3); A circular ring component (2) is arranged in the concave hexagonal structure (1), the circular ring component (2) comprising a chiral circular ring component (21) and two first extension arms (22), the center of the circle of the chiral circular ring component (21) coincides with the midpoint of a line connecting the center points of the two horizontal cell walls (11), the two first extension arms (22) are horizontally tangentially connected to the upper and lower ends of the chiral circular ring component (21), and the other ends of the two first extension arms (22) away from the chiral circular ring component (21) extend in opposite directions and are respectively connected to the inner inflection points (3) of the two inclined cell wall groups (12); the radius of the chiral circular ring component (21) is 1.5 mm-6.5 mm; The two first extension arms (22) are arranged parallel to the horizontal cell wall (11), and a height difference is formed between the inner inflection points (3) of the two groups of inclined cell wall groups, and the size of the height difference is equal to the diameter of the chiral circular ring member.

2. The highly impact-resistant concave chiral cell according to claim 1, characterized in that: The sum of the horizontal projection length of the inclined cell wall (121) and the length of the first extension arm (22) is equal to half the length of the horizontal cell wall (11).

3. The highly impact-resistant concave chiral cell according to claim 1, characterized in that: The wall thicknesses of the horizontal cell wall (11), the inclined cell wall, the chiral circular ring (21) and the first extension arm (22) are all 2 mm to 5 mm.

4. A honeycomb structure, characterized in that: It is composed of an arrangement and combination of the highly impact-resistant concave chiral cells described in any one of claims 1 to 3.

5. The honeycomb structure according to claim 4, characterized in that: The honeycomb structure is arranged in a plurality of columns in the horizontal direction and in a plurality of rows in the vertical direction; in each column, two adjacent concave chiral cells share a horizontal cell wall (11) for arrangement and combination; in each row, two adjacent concave chiral cells are connected by a first connecting member (4) provided, and the first connecting member (4) connects the inner inflection points (3) of the two adjacent concave chiral cells for arrangement and combination.

6. The honeycomb structure according to claim 5, characterized in that: In each row, the arrangement directions of two adjacent concave chiral cells are consistent, and the first connecting member (4) is an inclined connecting arm.

7. The honeycomb structure according to claim 6, characterized in that: In each row, positions of two adjacent concave chiral cells form a height difference, and the magnitude of the height difference is equal to the diameter of the chiral circular ring element.

8. The honeycomb structure according to claim 7, characterized in that: It also comprises a second connecting member (5), wherein the second connecting member (5) is a circular ring connecting arm.

9. The honeycomb structure according to claim 5, characterized in that: In each row, two adjacent concave chiral cells are arranged in mirror symmetry with each other, and the first connecting member (4) is a straight connecting arm or a circular connecting arm.

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