Multilayer honeycomb-like composite energy-absorbing structure and method of manufacturing

Abstract

The application belongs to the field of light structure products and its application, and discloses a preparation method of a multi-layer honeycomb-like composite energy absorption structure, which comprises the following steps: cutting and bending a sheet to be pasted to form a foldable sandwich structure, cutting a plurality of first sheets and second sheets with the same size and thickness; intervally applying an adhesive on the front surface of the first sheet to form a first front adhesive tape with a predetermined width, and forming a first front pasting block area between adjacent first front adhesive tapes; intervally applying an adhesive on the back surface of the first sheet, and aligning the center position of the first front pasting block area with each first back adhesive tape; applying an adhesive on the front surface and the back surface of the second sheet, aligning each second back adhesive tape with the first front adhesive tape of the first sheet of the last layer, and aligning each second front adhesive tape with the first back adhesive tape of the last layer; bonding the sandwich structure between each or part of the first sheet and the second sheet, stretching the first sheet and the last sheet, and obtaining the multi-layer honeycomb-like composite energy absorption structure.

Description

Technical Field

[0001] This invention belongs to the field of lightweight structural products and their applications, and particularly relates to a multi-layer honeycomb composite energy-absorbing structure and its preparation method. Background Technology

[0002] Currently, in addition to ensuring passenger safety, transportation vehicles such as high-speed trains, automobiles, ships, and airplanes must also gradually meet the increasingly urgent demand for lightweighting, leading to the widespread adoption of lightweight structures in the transportation sector. Hierarchical structures, particularly apex structures, are favored due to their excellent mechanical properties in terms of load-bearing capacity and impact resistance. Existing, relatively traditional hexagonal honeycomb energy-absorbing structures have many shortcomings in terms of load-bearing capacity, impact resistance, sound insulation, and thermal insulation. Increasing research has found that honeycomb-like structures, through hierarchical and hybrid designs, can significantly improve the load-bearing capacity and specific energy absorption of honeycombs, while also providing sound absorption and vibration isolation properties. However, due to their complex structure, these honeycombs typically require wire cutting, layer-by-layer bonding using molds, or 3D printing processes, making them difficult to manufacture using traditional methods. The high manufacturing cost significantly limits the engineering application of these honeycombs, necessitating the development of lower-cost, higher-load-bearing-capacity, and more impact-resistant honeycomb-like structure molding methods.

[0003] In the prior art, patent application number 201420135084.5 discloses an aluminum honeycomb energy-absorbing block, which includes an upper panel, a lower panel, and an aluminum honeycomb core. The aluminum honeycomb core is disposed between the upper panel and the lower panel. The aluminum honeycomb core is shaped like a cuboid, and its six sides are surrounded by edges. The aluminum honeycomb core includes multiple hexagonal prism platinum sheet cores, which are glued together by adhesive. The side length of the hexagonal prism platinum sheet core is greater than 2 mm, the thickness of the hexagonal prism platinum sheet core is 0.08 mm, the height of the aluminum honeycomb core is greater than 60 mm, and the interior of the aluminum honeycomb core is provided with mounting holes, the interior of which is filled with filler.

[0004] Patent application number 201610539128.4 discloses a honeycomb structure and design method for improving structural strength. The honeycomb structure of the present invention is composed of a periodically folded array of honeycomb cells. Periodic folding can improve the structural strength of the honeycomb structure in the coplanar direction. When the honeycomb structure is used as a buffer energy absorption structure, it can improve its energy absorption capacity. At the same time, the honeycomb structure has approximately isotropic characteristics. The honeycomb cells in each folding cycle are folded twice. The first folding direction is arbitrary, and the second folding direction is opposite to the first folding direction. The angle between the surface of the honeycomb cell after folding and the surface of the honeycomb cell before folding is between 10° and 34°. The periodically folded honeycomb cells are connected in series along the non-coplanar direction and then arrayed in the coplanar direction, which can effectively improve the structural strength of the honeycomb structure in the coplanar direction. Summary of the Invention

[0005] The technical problem to be solved by this invention is to overcome the shortcomings and defects mentioned in the background art above, and to provide a multilayer honeycomb-like composite energy-absorbing structure and its preparation method that can improve load-bearing capacity and impact resistance, and has low manufacturing cost and simple and controllable operation. To solve the above technical problem, the technical solution proposed by this invention is as follows: A method for preparing a multilayer honeycomb-like composite energy-absorbing structure includes: The sheet material to be pasted is cut and bent to form a foldable sandwich structure. The sandwich structure has a top surface and a bottom surface of the same length, and a folded side in the middle. After the side is folded, it fits into the top surface and the bottom surface. After the side is stretched, it forms a polygonal structure. Cut multiple sheets of the same size and thickness; the sheets include a first sheet and a second sheet; An adhesive is applied at equal intervals on the front side of the first sheet to form a first front adhesive tape of a predetermined width, and a first front patch area is formed between adjacent first front adhesive tapes. An adhesive is applied at equal intervals on the back of the first sheet to form a first back adhesive tape of a predetermined width. A first back adhesive patch area is formed between adjacent first back adhesive tapes, and each first back adhesive tape is aligned with the center position of the first front adhesive patch area. Adhesive is applied at equal intervals on the front side of the second sheet to form a second front adhesive tape of a predetermined width, and a second front patch area is formed between adjacent second front adhesive tapes. Adhesive is applied at equal intervals on the back of the second sheet to form a second back adhesive tape of a predetermined width. A second back adhesive patch area is formed between adjacent second back adhesive tapes. Each second back adhesive tape is aligned with the first front adhesive tape of the previous layer. Prepare multiple first sheets and second sheets, and bond a sandwich structure between each or part of the first sheets and second sheets, with the top and bottom surfaces of the sandwich structure aligned with the adhesive tape of the first sheets and second sheets. A reverse tensile force is applied to the center of the area to be pasted on the first and last sheets to stretch the folded sides of the sandwich structure, resulting in a multi-layer honeycomb composite energy-absorbing structure.

[0006] In one embodiment, the sheet is cut and bent to form a foldable sandwich structure with the connection ports located on the top and bottom surfaces. When the sandwich structure is bonded between the first and second sheets, the connection ports are bonded with adhesive tape.

[0007] In one embodiment, the lengths of the top and bottom surfaces of the sandwich structure are the same as the width of the adhesive tape, and the width of the area to be pasted on the first and second sheets is n times the width of the adhesive tape, where n ≥ 3.

[0008] In one embodiment, the sides of the sandwich structure are formed by multiple folds to form a serrated polygonal structure under incomplete stretching conditions; the folding form can be inward folding, outward folding, or a combination of folding.

[0009] In one embodiment, by adjusting the folding method and quantity of the sandwich structure between the first sheet and the second sheet, and changing the length of the adhesive tape and the side length of the sandwich structure, a honeycomb-like structure with various shape combinations can be obtained.

[0010] In one embodiment, multiple sets of stretching clamps with the same width as the adhesive tape are set at the center of the area to be pasted on the first sheet and the last sheet. The axial stretching movement and lateral movement of each clamp work together to stretch the folded side of the sandwich structure and bend the sheet to form a multi-layer honeycomb composite energy-absorbing structure.

[0011] Based on the same inventive concept, a multilayer honeycomb-like composite energy-absorbing structure prepared according to the preparation method described above is also provided.

[0012] In one embodiment, the multi-layered honeycomb composite energy-absorbing structure is composed of octagons and quadrilaterals, with adjacent octagons connected by quadrilaterals, and the sides of the quadrilaterals and the octagons sharing the same edge at the connection point.

[0013] In one embodiment, the multi-layered honeycomb composite energy-absorbing structure is composed of octagons, quadrilaterals, and hexagons, with one set of opposite sides of the quadrilaterals connecting adjacent hexagons and another set of opposite sides connecting adjacent octagons.

[0014] In one embodiment, the thickness of the sheet is 0.01 mm to 0.3 mm, and the sheet is a metal foil or a thin paper sheet.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The multi-layer honeycomb composite energy-absorbing structure obtained by the method of this application, compared with the existing traditional honeycomb structure mainly composed of hexagons, uses octagons as the main honeycomb cells. By introducing small cells (quadrilaterals or hexagons) in the node areas where the honeycomb cell walls intersect, the local stress concentration during the load-bearing process is reduced, the area of ​​equivalent plastic strain of the structure under impact or compression is expanded, and the deformation mode of the structure is greatly improved. Compared with the traditional honeycomb structure of the same mass, this structure achieves a significant increase in specific energy absorption under out-of-plane compression by more than 50% due to the introduction of local improvement features. Furthermore, by using the above-mentioned interlaced bonding to form basic sheet units, the sheets to be bonded are cut and bent to form a foldable sandwich structure. The sandwich structure is first folded to form corresponding bonded and non-bonded edges. After all the bonding is completed, it is stretched and unfolded to obtain a honeycomb shape combining various shapes (such as octagons, hexagons, and quadrilaterals). The operation is simple and controllable, and the manufacturing cost is greatly reduced compared with the previous layered and polygonal hybrid honeycomb structure molding solutions. At the same time, depending on the specific needs, a sandwich structure can be pasted between some of the first and second sheets, and no sandwich structure can be set between some of the first and second sheets. By adjusting the length of the pasting tape and the side length of the sandwich structure, a variety of custom-made honeycomb structures can be formed. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the front structure of the first sheet of a multi-layer honeycomb composite energy-absorbing structure according to one embodiment; Figure 2 A schematic diagram of the back side of the first sheet of a multi-layer honeycomb composite energy-absorbing structure according to one embodiment; Figure 3 A schematic diagram of a sandwich structure of a multi-layer honeycomb composite energy-absorbing structure according to one embodiment; Figure 4 This is a schematic diagram of the structure of a multi-layer honeycomb composite energy-absorbing structure before stretching (showing dimensions) according to one embodiment; Figure 5 This is a schematic diagram of the structure of a multi-layer honeycomb composite energy-absorbing structure before stretching (dimensions not shown) according to one embodiment; Figure 6A schematic diagram of the honeycomb structure after stretching and molding of a multi-layer honeycomb composite energy-absorbing structure according to one embodiment; Figure 7 This is a schematic diagram of the multi-layer honeycomb composite energy-absorbing structure before stretching, after ignoring the thickness of the adhesive tape, as one embodiment of the structure. Figure 8 This is a schematic diagram of the structure of a multi-layer honeycomb composite energy-absorbing structure after honeycomb stretching molding (adhesive tape not shown) according to one embodiment. Figure 9 A schematic diagram of the cell stretching process of a multi-layer honeycomb composite energy-absorbing structure according to one embodiment; Figure 10 This is a schematic diagram of the stretched structure of a multi-layered honeycomb composite energy-absorbing structure according to another embodiment. Figure 11 This is a schematic diagram of the stretched structure of a multi-layered honeycomb composite energy-absorbing structure according to another embodiment. Detailed Implementation

[0018] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0019] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0020] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0021] Please see Figure 1-11 A method for preparing a multilayer honeycomb-like composite energy-absorbing structure, comprising: S1. Cut and bend the sheet material to be pasted to form a foldable sandwich structure. The sandwich structure has a top and bottom surface of equal length, and symmetrical folded sides in the middle. After the sides are folded, the top and bottom surfaces are attached. After the sides are stretched, a polygonal structure is formed. It is generally quadrilateral.

[0022] Specifically, such as Figure 3 As shown in Figure a, the top and bottom surfaces are parallel, and both have a length of L3, meaning they are the same length. Figure 3As shown in Figure b, the overall length of the sandwich structure is W. The sandwich structure is a three-dimensional structure with a quadrilateral cross-section, which flattens after folding. The side located between the bottom and top surfaces is the folded side, formed through multiple folds, creating a serrated polygonal structure under incomplete stretching conditions; the folding form can be inward folding, outward folding, or a combination of folding. The folding method can be as follows... Figure 3 As shown in figure a, the concave fold can be replaced by an outward fold in other embodiments, forming a crease. Preferably, there is only one crease on each side, located on the central axis of the folded side, resulting in a symmetrical fold. This minimizes the number of folds and is the most convenient and quickest method. In specific embodiments, the folded side may also have multiple creases.

[0023] It should be noted that step S1 can be completed before or after the first and second sheet processing. Considering the curing time of the adhesive, step S1 is preferably completed first.

[0024] S2. Cut multiple sheets of the same size and thickness; the sheets include a first sheet and a second sheet.

[0025] To form a multi-layered honeycomb structure, a corresponding number of sheets can be cut according to the required number of layers. The first and second sheets are identical in material, shape, and size; the only difference is the location where the adhesive is applied.

[0026] Specifically, the sheet thickness is 0.01mm~0.3mm, and the sheet can be metal foil or thin paper. The sheet is cut into multiple rectangles of equal length and width, where the length of each rectangle is... The width of the rectangle is .in The direction refers to the thickness of the honeycomb structure after stretching and forming. Therefore, the overall length of the sandwich structure is W, consistent with the first and second sheets.

[0027] S3. Apply adhesive to the front side of the first sheet at intervals to form a first front adhesive tape of a predetermined width, and form a first front patch area between adjacent first front adhesive tapes.

[0028] Specifically, please refer to Figure 1 In one embodiment, the width of the first front adhesive tape is L1, and a first front adhesive area to be pasted is formed between adjacent first front adhesive tapes, the width of which is L2. The width of L2 is greater than the width of L1, so that there is space to correspond when adhesive tape is formed on the back side.

[0029] S4. Apply adhesive at intervals to the back of the first sheet to form a first back adhesive tape of a predetermined width, and form a first back adhesive patch area between adjacent first back adhesive tapes, with each first back adhesive tape aligned with the center of the first front adhesive patch area.

[0030] Specifically, please refer to Figure 2 In one embodiment, the width of the first back adhesive tape is L1, and a first front adhesive area to be pasted is formed between adjacent first front adhesive tapes, the width of which is L2. The width of L2 is greater than the width of L1, so that there is space to correspond when it is opposite to the second sheet.

[0031] S5. Apply adhesive to the front side of the second sheet at intervals to form a second front adhesive tape of a predetermined width, and form a second front patch area between adjacent second front adhesive tapes.

[0032] S6. Apply adhesive at intervals to the back of the second sheet to form a second back adhesive tape of a predetermined width. Form a second back adhesive patch area between adjacent second back adhesive tapes. Each second back adhesive tape is aligned with the first front adhesive tape of the first sheet above it. Each second front adhesive tape is aligned with the first back adhesive tape of the first sheet above it.

[0033] The second sheet is formed in the same way as the first sheet, and the widths of the second front adhesive tape and the second back adhesive tape are also L1, and the widths of the second front area to be pasted and the second back area to be pasted are also L2.

[0034] S7. Prepare multiple first sheets and second sheets, and glue a sandwich structure between each or part of the first sheets and second sheets, with the top and bottom surfaces of the sandwich structure aligned with the adhesive tape of the first sheets and second sheets. In one embodiment, after the first sheet is fabricated, the top surfaces of multiple sandwich structures are first bonded to the front or back (one of the sides) of the first sheet using adhesive tape, and then the second sheet is fabricated and bonded to the bottom surface of the sandwich structure. In another embodiment, the first and second sheets can be fabricated first, and then the sandwich structure can be bonded between them.

[0035] Depending on the required number of layers, the process of bonding multiple sandwich structures between each first and second sheet can be repeated, or the process of bonding multiple sandwich structures between a portion of the first and second sheets can be repeated. This yields multi-layered honeycomb-like composite energy-absorbing structures with different polygonal shapes. By adjusting the folding method and number of sandwich structures between the first and second sheets, and changing the length of the adhesive tape and the side lengths of the sandwich structures, honeycomb-like structures with various shape combinations can be obtained. For example, specifically, in one embodiment, multiple sandwich structures are bonded between each first sheet and second sheet to obtain a multi-layered honeycomb-like composite energy-absorbing structure with octagonal and quadrilateral shapes. Bonding multiple sandwich structures between portions of the first sheet and second sheet can yield a multi-layered honeycomb-like composite energy-absorbing structure with a mixture of octagonal, hexagonal, and quadrilateral shapes.

[0036] Specifically, in one embodiment, the lengths of the top and bottom surfaces of the sandwich structure are the same as the width of the adhesive tape. The width of the area to be bonded on the first and second sheets is n times the width of the adhesive tape, where n ≥ 3. For example, when n is 3, it is an octagonal structure. Of course, in other embodiments, this width can be set as needed to obtain different polygonal structures. By bonding multiple sandwich structures between each first and second sheet, regular octagonal, square, or hybrid multilayer honeycomb composite energy-absorbing structures can be obtained. That is, the length of the folded side of the sandwich structure after stretching is the same as the lengths of the top and bottom surfaces, and the stretched sandwich structure is square.

[0037] S8. Apply reverse tensile force to the first and last sheets to stretch the folded sides of the sandwich structure to obtain a multi-layer honeycomb composite energy-absorbing structure.

[0038] Specifically, a reverse tensile force is applied to the first and last sheets using clamps to stretch the folded sides of the sandwich structure, resulting in a multi-layered honeycomb-like composite energy-absorbing structure.

[0039] Please see Figure 9 During stretching, the cell stretching and forming process is as follows: Figure 9 As shown in Figure ABCD, during the stretching process, the angle between the folded side of the sandwich structure and the top or bottom surface gradually increases, then approaches a quadrilateral, and finally forms a quadrilateral. When the lengths of the folded side, top surface, and bottom surface are the same, a square is obtained. At the same time, during the stretching process, an octagon gradually forms between the four quadrilaterals.

[0040] The present invention also provides a multilayer honeycomb composite energy-absorbing structure obtained by the preparation method described above.

[0041] In one embodiment, the multi-layered honeycomb composite energy-absorbing structure is composed of octagons and quadrilaterals, with adjacent octagons connected by quadrilaterals, and the sides of the quadrilaterals sharing edges with the octagons at the connection points. In another embodiment, the multi-layered honeycomb composite energy-absorbing structure is composed of octagons, quadrilaterals, and hexagons, with one set of opposite sides of the quadrilaterals connecting to adjacent hexagons, and another set of opposite sides connecting to adjacent octagons. The quadrilaterals, depending on the lengths of their base and top sides and the folded side edges, can be stretched into squares or rectangles.

[0042] In one embodiment, the thickness of the sheet is 0.01 mm to 0.3 mm, and the sheet is a metal foil or aramid paper.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows: The multi-layer honeycomb composite energy-absorbing structure obtained by the method of this application, compared with the existing traditional honeycomb structure mainly composed of hexagons, uses octagons as the main honeycomb cells. By introducing small cells (quadrilaterals or hexagons) in the node areas where the honeycomb cell walls intersect, the local stress concentration during the load-bearing process is reduced, the area of ​​equivalent plastic strain of the structure under impact or compression is expanded, and the deformation mode of the structure is greatly improved. Compared with the traditional honeycomb structure of the same mass, this structure achieves a significant increase in specific energy absorption under out-of-plane compression by more than 50% due to the introduction of local improvement features. Furthermore, by using the above-mentioned interlaced bonding to form basic sheet units, the sheets to be bonded are cut and bent to form a foldable sandwich structure. The sandwich structure is first folded to form corresponding bonded and non-bonded edges. After all the bonding is completed, it is stretched and unfolded to obtain a honeycomb shape combining various shapes (such as octagons, hexagons, and quadrilaterals). The operation is simple and controllable, and the manufacturing cost is greatly reduced compared with the previous layered and polygonal hybrid honeycomb structure molding solutions. At the same time, depending on the specific needs, a sandwich structure can be pasted between some of the first and second sheets, and no sandwich structure can be set between some of the first and second sheets. By adjusting the length of the pasting tape and the side length of the sandwich structure, a variety of custom-made honeycomb structures can be formed.

Claims

1. A method for preparing a multilayer honeycomb-like composite energy-absorbing structure, characterized in that, Includes the following steps: The sheet material to be pasted is cut and bent to form a foldable sandwich structure. The sandwich structure has a top and bottom surface of the same length, and a folded side in the middle. After the side is folded, it fits into the top and bottom surfaces. After the side is stretched, it forms a quadrilateral structure. The connection ports of the foldable sandwich structure formed by cutting and bending the sheet material are located on the top and bottom surfaces. Cut multiple sheets of the same size and thickness; the sheets include a first sheet and a second sheet; An adhesive is applied at equal intervals on the front side of the first sheet to form a first front adhesive tape of a predetermined width, and a first front patch area is formed between adjacent first front adhesive tapes. The width of the first front area to be pasted is greater than the width of the first front adhesive tape; An adhesive is applied at equal intervals on the back of the first sheet to form a first back adhesive tape of a predetermined width. A first back adhesive patch area is formed between adjacent first back adhesive tapes, and each first back adhesive tape is aligned with the center position of the first front adhesive patch area. Adhesive is applied at equal intervals on the front side of the second sheet to form a second front adhesive tape of a predetermined width, and a second front patch area is formed between adjacent second front adhesive tapes. Adhesive is applied at equal intervals on the back of the second sheet to form a second back adhesive tape of a predetermined width. A second back adhesive patch area is formed between adjacent second back adhesive tapes. Each second back adhesive tape is aligned with the first front adhesive tape of the previous layer. Prepare multiple first sheets and second sheets, and glue a sandwich structure between each first sheet and second sheet, with the top and bottom surfaces of the sandwich structure aligned with the adhesive tape of the first sheet and second sheet; The connection ports are glued together with adhesive tape; A reverse tensile force is applied to the center of the area to be pasted on the first and last sheets to stretch the folded sides of the sandwich structure, resulting in a multi-layered honeycomb composite energy-absorbing structure composed of octagons and quadrilaterals.

2. A method for preparing a multilayer honeycomb-like composite energy-absorbing structure, characterized in that, Includes the following steps: The sheet material to be pasted is cut and bent to form a foldable sandwich structure. The sandwich structure has a top and bottom surface of the same length, and a folded side in the middle. After the side is folded, it fits into the top and bottom surfaces. After the side is stretched, it forms a quadrilateral structure. The connection ports of the foldable sandwich structure formed by cutting and bending the sheet material are located on the top and bottom surfaces. Cut multiple sheets of the same size and thickness; the sheets include a first sheet and a second sheet; An adhesive is applied at equal intervals on the front side of the first sheet to form a first front adhesive tape of a predetermined width, and a first front patch area is formed between adjacent first front adhesive tapes. The width of the first front area to be pasted is greater than the width of the first front adhesive tape; An adhesive is applied at equal intervals on the back of the first sheet to form a first back adhesive tape of a predetermined width. A first back adhesive patch area is formed between adjacent first back adhesive tapes, and each first back adhesive tape is aligned with the center position of the first front adhesive patch area. Adhesive is applied at equal intervals on the front side of the second sheet to form a second front adhesive tape of a predetermined width, and a second front patch area is formed between adjacent second front adhesive tapes. Adhesive is applied at equal intervals on the back of the second sheet to form a second back adhesive tape of a predetermined width. A second back adhesive patch area is formed between adjacent second back adhesive tapes. Each second back adhesive tape is aligned with the first front adhesive tape of the previous layer. Prepare multiple first sheets and second sheets, and bond a sandwich structure between a portion of the first sheets and second sheets, with the top and bottom surfaces of the sandwich structure aligned with the adhesive tape of the first sheets and second sheets; The connection ports are glued together with adhesive tape; A reverse tensile force is applied to the center of the area to be pasted on the first and last sheets to stretch the folded sides of the sandwich structure, resulting in a multi-layered honeycomb composite energy-absorbing structure composed of octagons, hexagons, and quadrilaterals.

3. The method for preparing a multi-layered honeycomb composite energy-absorbing structure according to claim 1 or 2, characterized in that, The lengths of the top and bottom surfaces of the sandwich structure are the same as the width of the adhesive tape. The width of the area to be pasted on the first and second sheets is n times the width of the adhesive tape, where n ≥ 3.

4. The method for preparing a multi-layered honeycomb composite energy-absorbing structure according to claim 1 or 2, characterized in that, The sides of the sandwich structure are formed by multiple folds, resulting in a serrated polygonal structure under incomplete stretching conditions; the folding methods include inward folding, outward folding, or combined folding.

5. The method for preparing a multi-layered honeycomb composite energy-absorbing structure according to claim 1 or 2, characterized in that, Multiple sets of stretching clamps with the same width as the adhesive tape are set at the center of the area to be pasted on the first and last sheets. The axial stretching and lateral movement of each clamp work together to stretch the folded sides of the sandwich structure and bend the sheets to form a multi-layer honeycomb composite energy-absorbing structure.

6. A multilayer honeycomb-like composite energy-absorbing structure obtained by the preparation method according to claim 1, characterized in that, The multi-layered honeycomb composite energy-absorbing structure is composed of octagons and quadrilaterals. Adjacent octagons are connected by quadrilaterals, and the sides of the quadrilaterals and octagons share the same edge at the connection point.

7. A multilayer honeycomb-like composite energy-absorbing structure obtained by the preparation method according to claim 2, characterized in that, The multi-layered honeycomb composite energy-absorbing structure is composed of octagons, quadrilaterals, and hexagons. One set of opposite sides of the quadrilaterals connects to adjacent hexagons, and another set of opposite sides connects to adjacent octagons.

8. The multi-layered honeycomb composite energy-absorbing structure according to claim 6 or 7, characterized in that, The thickness of the sheet is 0.01mm to 0.3mm, and the sheet is a metal foil or a thin paper sheet.

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