A preparation method of aperiodic ordered fiber reinforced honeycomb structure based on long tube forming, slitting and assembling

Abstract

A preparation method of non-periodic ordered fiber reinforced honeycomb structure based on long tube forming, cutting and assembling, comprising the following steps: (1) unit long tube forming: S1_1. unit long tube preforming, S1_2. packaging and pressing of the preformed unit long tubes, S1_3. one-time hot pressing forming and demolding of the group unit long tubes; (2) cutting and assembling honeycomb structure: S2_1. forming unit cutting, S2_2. adhesive arrangement of the forming units, S2_3. overall pressure forming of the honeycomb structure. The process flow is simple, the preparation period is short, the supporting tooling mold consumption is small, and the production cost can be effectively controlled. Meanwhile, the tooling of the application has strong universality, and can be adapted to various non-periodic ordered topological configurations by only changing the shape of the long tube hot pressing forming mold, without changing the assembling and pressure forming device, which can provide technical support for the engineering popularization and large-scale production of non-periodic ordered composite honeycomb structure.

Description

Technical Field

[0001] This invention belongs to the field of composite material processing and manufacturing technology, and relates to a process method for preparing fiber-reinforced honeycomb structures. It is particularly suitable for the preparation of fiber-reinforced honeycomb structures with non-periodic ordered topological configurations, and can also meet the molding requirements of various periodic and variable parameter gradient fiber-reinforced honeycomb structures. Background Technology

[0002] Aperiodic order refers to long-range spatial ordering that does not satisfy periodic arrangement characteristics. Thanks to continuous innovation and development in aperiodic topology theory, from the classic Penrose tiling to the first truly aperiodic single-pile tiling—hat tiling—aperiodic geometric systems have been continuously enriched. Research has found that compared to traditional periodic honeycomb structures, aperiodic ordered honeycomb structures exhibit more unique and superior mechanical properties. These structures not only demonstrate excellent elastic isotropy but also retain a high number of node connections while breaking periodic symmetry. This means that at the same relative density, aperiodic honeycomb structures can bear greater loads and have a more uniform internal stress distribution, effectively avoiding the "weak chain" effect commonly found in random porous materials. Fiber-reinforced composite materials, such as fiber-reinforced composites, have unique advantages in improving structural efficiency. If they can be used as a base material to develop aperiodic ordered honeycomb structures, it will greatly enhance their engineering application potential in demanding fields such as aerospace, automotive lightweighting, and protective engineering.

[0003] However, significant technical bottlenecks remain in the engineering fabrication of aperiodic ordered composite honeycombs. First, traditional fiber-reinforced composite honeycomb fabrication processes are ill-suited for aperiodic configurations. Traditional fabrication methods (such as corrugation, stretching, hot-pressing folding, or interlocking assembly) heavily rely on the "periodicity" and "translational symmetry" of the structural arrangement. Aperiodic ordered structures, lacking global symmetry and containing various irregular polygonal lattices and complex node connections, render traditional molding processes completely ineffective. Specifically, corrugation and stretching methods cannot handle non-uniform node distribution characteristics, while interlocking methods easily lead to fiber continuity disruption and severe assembly space interference in aperiodic topological networks.

[0004] Patent document CN120645489A discloses a process method using "integral co-curing molding," which directly assembles uncured soft prepreg units and then uses a dedicated external mold for complete integral pressure curing. This process method has two major drawbacks in practical applications: First, the uncured prepreg is soft and prone to problems such as pore wall bending, extrusion deformation, surface wrinkling, and fiber misalignment when facing complex aperiodic splicing and integral extrusion. This results in deviations in the geometric shape of the honeycomb lattice units after molding, and misalignment of the splicing positions of each lattice is likely to occur. These molding defects are particularly pronounced when preparing large-size honeycomb components, weakening the original mechanical advantages of the aperiodic ordered structure. Secondly, the outer edges of aperiodic ordered topological honeycomb structures are mostly irregular serrated or complex polygons. To achieve edge constraints during the overall pressurization process, existing technologies require the customization of rigid boundary shaping molds of corresponding specifications based on different topological styles and structural dimensions. When adjusting the structural dimensions, height, and arrangement of the honeycomb, the original set of peripheral molds will be unsuitable and need to be redesigned and processed. As the overall size of the honeycomb increases, the number of supporting shaping modules increases exponentially, leading to a significant increase in manufacturing costs. Therefore, the molds involved in this method have weak versatility, which will limit its flexible customization capabilities and low-cost mass production applications in the engineering field. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing fiber-reinforced honeycomb structures suitable for non-periodic ordered special topological configurations, solving the problems that traditional honeycomb molding processes are not applicable, and that existing publicly available processes have insufficient preparation accuracy and weak mold versatility, thus giving full play to the high strength and high toughness performance advantages and engineering application potential of this type of structure.

[0006] The technical solution of this invention is: a method for preparing a non-periodic ordered fiber-reinforced honeycomb structure based on long tube forming, slitting, and assembly, adapted to the special topological characteristics of non-periodic ordered honeycomb structures: densely packed with basic units of single or multiple geometric shapes and their mirror-flipped units, exhibiting long-range order without global translational symmetry when infinitely extended in a plane. The preparation process includes two main steps:

[0007] (a) Forming of a single long tube:

[0008] S1_1. Unit Long Tube Preforming: First, assemble the long tube support core mold 5, whose cross-sectional shape is consistent with the basic unit. To ensure efficient demolding, the long tube support core mold is assembled from multiple long strip cores 5_1, 5_2, ..., 5_9. Cut the prepreg into rectangular strips, the length of which is equal to the length of the long tube support core mold 5, and the width is determined according to the perimeter of the basic unit and the thickness t of the honeycomb cell wall. Wrap the prepreg strips around the assembled long tube support core mold 5, the number of wrapping layers being the width of the prepreg strip divided by the perimeter of the long tube support core mold. Repeat the above operations to obtain the target number of unit long tube preforms.

[0009] S1_2. Packaging and pressing of grouped preformed unit tubes: First, apply release agent evenly to the inner surfaces of the upper mold 3 and lower mold 4 of the packaging box; then place the preformed unit tube obtained in S1_1 into the lower mold 4 of the packaging box and achieve a tight fit; next, cover the preformed unit tube with the upper mold 3 of the packaging box to close the mold, so that the preformed unit tube in the closed cavity can be evenly compressed; then, insert the assembled packaging box into the groove of the base plate 2; repeat the above operation to close the mold of the grouped packaging boxes one by one and insert them into the groove of the base plate 2; finally, place the top plate 1 flat on top of the fixed grouped packaging boxes according to the groove position, and the packaging and pressing of the grouped preformed unit tubes can be completed.

[0010] S1_3. One-time hot pressing and demolding of grouped unit long tubes: Place the complete set of devices obtained in S1_2 into an electric heating drying oven, maintain a pressure of not less than 0.5MPa, set the heating temperature to 80℃ and maintain it for 30 minutes, then set the heating temperature to 130℃ and maintain it for 2 hours. After that, turn off the power and let it cool naturally. Take the complete set of devices out of the electric heating drying oven; remove the top plate 1 in sequence, take out the packaging box, and separate the upper mold and lower mold of the packaging box; first knock out the middle long strip core, then take out the peripheral long strip cores in sequence. Repeat the above operation to achieve one-time hot pressing and demolding of grouped basic unit long tubes.

[0011] (II) Segmentation and assembly of honeycomb structure:

[0012] S2_1. Molding unit cutting: According to the preset honeycomb structure height, the demolded unit tube 6 is cut laterally along its length to obtain the basic molding unit; repeat this operation until the target number of polygonal molding units are obtained.

[0013] S2_2. Molding Unit Bonding and Arrangement: Based on the preset non-periodic ordered topological configuration, the molding units (including some mirror-flipped units) obtained in S2_1 are arranged and spliced ​​tightly from the inside to the outside. Structural adhesive is applied to the joint surface of adjacent units for bonding, and pre-pressing is implemented to fix each molding unit to keep it stable and without loosening. Repeat this operation until a pre-formed structure with a complete topological shape is obtained.

[0014] S2_3. Honeycomb Structure Pressure Molding: The preformed structure obtained in S2_2 is placed on the base plate 7 in the assembly pressure molding device, so that its four sides are respectively connected to the L-shaped flexible bonding strip 9, the transverse flexible bonding strip 10 and the longitudinal flexible bonding strip 11; then the transverse movable pressure strip 12 abuts against the transverse flexible bonding strip 10, and the longitudinal movable pressure strip 13 abuts against the longitudinal flexible bonding strip 11; the adjusting bolt 14 on the fixed frame 8 is screwed to drive the transverse movable pressure strip 12 and the longitudinal movable pressure strip 13 to apply pressure synchronously, thereby applying a uniform circumferential clamping force to the splicing unit blocks obtained in S2_2; with the adaptive deformation of all the flexible bonding strips and their full circumferential fit with the preformed structure, the pressure on each unit is uniform, which promotes the uniform spread of the adhesive and achieves tight bonding between each unit; the applied clamping pressure is controlled between 0.1-0.3MPa according to the size of the honeycomb structure and the viscosity of the structural adhesive. After 24 hours, loosen bolt 14 and remove transverse movable pressure strip 12, longitudinal movable pressure strip 13, transverse flexible bonding strip 10, and longitudinal flexible bonding strip 11 in sequence to obtain the preset shaped honeycomb structure.

[0015] Furthermore, the geometric shape and size parameters of the cross section of the long tube support core mold 5 are consistent with the shape and internal dimensions of the basic unit in the aperiodic ordered honeycomb structure. In order to achieve efficient demolding, the long tube support core mold 5 is assembled from multiple long strip cores to adapt to the complex geometric shape of the basic unit, such as the thirteen-sided polygon in the hat inlay topology.

[0016] Furthermore, the packaging box includes an upper mold 3 and a lower mold 4. The upper mold 3 adopts a split structure, consisting of two parts joined together to facilitate demolding. The inner enclosure contour formed by the upper and lower molds is consistent with the contour of the matching long tube support core mold 5, and the uniform fitting gap between the two in the coaxial state is equal to t / 2, that is, 1 / 2 of the design dimension of the cell wall thickness of the honeycomb structure, so as to ensure that the preformed unit long tube is tightly fitted with the long tube support core mold 5 and the inner cavity of the packaging box at the same time.

[0017] Furthermore, the top plate 1 and bottom plate 2 of the hot pressing forming device are provided with several grooves. The assembled packaging box is inserted into the grooves and forms a small interference fit, thereby realizing uniform circumferential pressure on the pre-formed unit long tube.

[0018] Furthermore, the assembly and pressure molding device includes a base plate 7, a fixed frame 8, a transverse movable pressure strip 12, a longitudinal movable pressure strip 13, an L-shaped flexible bonding strip 9, a transverse flexible bonding strip 10, and a longitudinal flexible bonding strip 11; wherein, the outer wall of the L-shaped flexible bonding strip is tightly bonded to the two adjacent inner walls of the fixed frame 8; the transverse flexible bonding strip 10 and the longitudinal flexible bonding strip 11 are tightly bonded to the transverse movable pressure strip 12 and the longitudinal movable pressure strip 13, respectively; the preformed structure is placed in the space enclosed by the flexible bonding strips, and by tightening the adjusting bolts, the circumferential uniform pressure of the preformed structure is achieved by the synergistic effect of the outer rigid frame and the inner flexible frame; the assembly and pressure molding device can be adapted to the design requirements of honeycomb structures with different outer edges by relying on the adaptive deformation of the flexible bonding strips.

[0019] Furthermore, during the pressurization process of the honeycomb structure, the applied clamping pressure should be controlled between 0.1 and 0.3 MPa. When the clamping pressure is below 0.1 MPa, the bonding interface is not sufficiently compressed, which cannot effectively expel interface air bubbles or ensure sufficient wetting of the unit surface by the adhesive. When the clamping pressure is above 0.3 MPa, excessive pressure will squeeze out most of the effective adhesive layer in the bonding surface, and may also cause local micro-bending of the honeycomb structure or debonding of the fiber-matrix interface, ultimately leading to a decrease in the overall molding strength of the structure.

[0020] Furthermore, the long tube support core mold 5 is made of polytetrafluoroethylene (PTFE) material to facilitate demolding; the top plate 1, bottom plate 2, and upper mold 3 and lower mold 4 of the hot pressing molding device are all made of metal material to ensure pressure strength and facilitate uniform temperature conduction; the L-shaped flexible bonding strip 9, transverse flexible bonding strip 10, and longitudinal flexible bonding strip 11 of the assembly pressure molding device can be made of silicone or TPU material to utilize their adaptive deformation to tightly fit the pre-formed structure circumferentially; the bottom plate 7, fixed frame 8, transverse movable pressure strip 12, and longitudinal movable pressure strip 13 of the assembly pressure molding device are all made of metal material to meet the pressure strength requirements.

[0021] Furthermore, the topological configuration of the aperiodic ordered fiber reinforced honeycomb structure is derived from a jigsaw puzzle type that has been proven by mathematicians to have aperiodic tessellation characteristics, and a piece of the required pattern is cut out from an infinite tessellation plane, including but not limited to hat tessellation, turtle tessellation, Penrose tessellation type P1, P2, P3, etc.

[0022] Furthermore, the preparation method has multi-dimensional adjustable adaptability; it can not only prepare honeycomb structures with uniform wall thickness, but also meet the preparation requirements of honeycomb structures with varying thickness and size gradient; it can be used not only to prepare non-periodic ordered honeycomb structures, but also to prepare periodic honeycomb structures such as chiral honeycomb and hybrid honeycomb.

[0023] Furthermore, the preparation method may also include a post-processing step if necessary: ​​according to the design requirements of the honeycomb structure size, removing excess material by mechanical processing and polishing burrs.

[0024] The beneficial effects of adopting the above technical solution in this invention are as follows:

[0025] 1. This invention adopts a novel approach of hot-pressing grouped unit long tubes in one step and then splicing and curing the basic units after cutting them. This approach can not only adapt to special topological configurations with long-range order but no global translational symmetry, but also significantly improve the preparation efficiency and molding accuracy, and greatly improve the preparation defects such as geometric deformation of honeycomb lattice units and misalignment of splicing of each lattice.

[0026] 2. In the process of hot pressing and forming group unit long tubes, the present invention, through the design of the fit gap between the upper and lower molds of the packaging box and the long tube support core mold, can make the preformed unit long tube fit tightly with the inner and outer molds and be evenly stressed, effectively avoiding defects such as deformation and wrinkles in the fiber prepreg.

[0027] 3. The process strategy of "first forming the unit long tube, then cutting and splicing" adopted in this invention can effectively ensure the consistency of each cell unit in the honeycomb structure. At the same time, this process can remove the basic units with defects in a timely manner during the preparation process, overcoming the problem that the existing disclosed technology cannot correct the preparation defects by using the overall hot pressing process, and greatly improving the preparation qualification rate of non-periodic ordered honeycomb structure.

[0028] 4. This invention uses soft materials such as silicone to design flexible bonding strips. Relying on their adaptive deformation and working in conjunction with the outer rigid frame, it achieves uniform circumferential pressure on the preformed structure. This effectively solves the problems of irregular edge height of non-periodic honeycomb structures, poor bonding effect of traditional rigid molds, and low versatility. It not only ensures uniform pressure and reliable bonding of each cell unit, but also effectively simplifies the preparation process and reduces mold costs.

[0029] 5. This invention can adapt to different height requirements of honeycomb structures by simply adjusting the axial cutting spacing of the long tube, effectively improving the adaptability of customized production and mass production of aperiodic ordered honeycomb structures. At the same time, the tooling of this invention has strong versatility; only the shape of the long tube hot-pressing mold needs to be changed to adapt to various aperiodic ordered topological configurations, without modifying the assembly and pressurizing device, further enhancing the versatility and engineering practicality of the process and tooling. Attached Figure Description

[0030] Figure 1 This is a flowchart of the main steps of the preparation method of the present invention.

[0031] Figure 2 This is a schematic diagram of the overall structure, bottom plate, and top plate of the group unit long tube one-time hot pressing forming device of the present invention.

[0032] Figure 3 This is a schematic diagram of the unit long tube support core mold of the present invention.

[0033] Figure 4 This is a schematic diagram of the preforming of the unit long tube according to the present invention.

[0034] Figure 5 This is a schematic diagram of the unit long tube packaging and molding of the present invention.

[0035] Figure 6 This is a schematic diagram showing the cutting of the unit tube and the forming unit of the present invention.

[0036] Figure 7 This is a schematic diagram of the honeycomb structure pressure molding of the present invention.

[0037] Figure 8 This is a schematic diagram of the assembly and pressure molding device of the present invention.

[0038] Figure 9 This is a schematic diagram illustrating the trimming of excess material after the hat-shaped honeycomb structure has been formed, according to the present invention.

[0039] Figure 10 (a) and (b) are schematic diagrams of the present invention adapted to the Penrose inlay P2 type honeycomb structure group kite-shaped unit long tube one-time hot pressing forming device and dart-shaped unit long tube one-time hot pressing forming device.

[0040] Figure 11 This is a schematic diagram illustrating the removal of excess material and trimming after the Penrose inlay P2 type honeycomb structure is formed, according to the present invention.

[0041] In the diagram: 1-Top plate of the hot press forming device; 2-Base plate of the hot press forming device; 3-Upper mold of the unit long tube packaging box; 4-Lower mold of the unit long tube packaging box; 5-Supporting core mold of the unit long tube; 6-Forming unit long tube; 7-Base plate of the assembly pressure forming device; 8-Fixed frame; 9-L-shaped flexible bonding strip; 10-Horizontal flexible bonding strip; 11-Vertical flexible bonding strip; 12-Horizontal movable pressure strip; 13-Vertical movable pressure strip; 14-Adjusting bolt; 15-Kite-shaped long tube support core mold; 16-Upper mold of the kite-shaped packaging box; 17-Lower mold of the kite-shaped packaging box; 18-Supporting core mold of the dart-shaped long tube; 19-Upper mold 1 of the dart-shaped packaging box; 20-Lower mold 20 of the dart-shaped packaging box. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments. However, the scope of protection of the present invention is not limited thereto.

[0043] Example 1.

[0044] This paper describes an aperiodic ordered fiber-reinforced honeycomb structure based on a partial pattern derived from a hat mosaic, with a single thirteen-sided polygon as its basic unit. The fabrication process utilizes a one-time hot-pressing molding device for grouped unit long tubes, such as... Figure 2 As shown, it includes a top plate 1 and a bottom plate 2, a unit long tube support core mold 5, and a unit long tube encapsulation box upper mold 3 and lower mold 4.

[0045] The long tube support core mold 5 is composed of 9 long strip cores, such as... Figure 3 As shown, its cross-sectional shape and size parameters are consistent with the shape and internal dimensions of the basic unit in the honeycomb structure, and it is preferably made of easy-to-demold materials (such as polytetrafluoroethylene).

[0046] Single-cell long tube packaging box such as Figure 5 As shown, it includes an upper mold 3 and a lower mold 4. The upper mold 3 adopts a split structure, which is composed of two parts to achieve convenient demolding. The inner contour formed by the upper and lower molds is consistent with the contour of the matching long tube support core mold 5. The uniform fit gap between the two in the coaxial state is 1 / 2 of the design size of the honeycomb structure cell wall thickness, so as to ensure that the preformed unit long tube is tightly fitted with the long tube support core mold 5 and the inner cavity of the packaging box at the same time.

[0047] Assemble pressure molding device such as Figure 8 As shown, it includes a base plate 7, a fixed frame 8, a transverse movable pressure strip 12, a longitudinal movable pressure strip 13, an L-shaped flexible bonding strip 9, a transverse flexible bonding strip 10, and a longitudinal flexible bonding strip 11; the L-shaped flexible bonding strip 9, the transverse flexible bonding strip 10, and the longitudinal flexible bonding strip 11 are preferably made of silicone or TPU materials to take advantage of their adaptive deformation characteristics.

[0048] The main steps of the preparation method in this embodiment are as follows: Figure 1 As shown, it specifically includes:

[0049] (a) Forming of a single long tube:

[0050] S1_1. Unit Long Tube Preforming: First, assemble the long tube support core mold 5, whose cross-sectional shape is consistent with the basic unit. To ensure efficient demolding, the long tube support core mold is assembled from multiple long strip cores 5_1, 5_2, ..., 5_9. Cut the prepreg into rectangular strips, the length of which is equal to the length of the long tube support core mold 5, and the width is determined according to the perimeter of the basic unit and the thickness t of the honeycomb cell wall. Wrap the prepreg strips around the assembled long tube support core mold 5, such as... Figure 4 As shown, the number of winding layers is the width of the prepreg strip divided by the circumference of the long tube support mandrel; repeating the above operation will yield the target number of unit long tube preforms.

[0051] S1_2. Packaging and pressing of preformed unit tubes: First, evenly apply a release agent to the inner surfaces of the upper mold 3 and lower mold 4 of the packaging box; then place the preformed unit tubes obtained in S1_1 into the lower mold 4 of the packaging box and achieve a tight fit; next, cover the preformed unit tubes with the upper mold 3 of the packaging box to close the mold, so that the preformed unit tubes placed in the closed cavity can be evenly compressed, such as... Figure 5 As shown; then, insert the assembled packaging box into the groove of the base plate 2; repeat the above operation, mold the group of packaging boxes one by one and insert them into the groove of the base plate 2; finally, place the top plate 1 flat on top of the fixed group of packaging boxes according to the groove position, thus completing the packaging and pressing of the group of pre-formed unit long tubes, as shown. Figure 2 As shown, both the top plate 1 and the bottom plate 2 have several grooves. The encapsulation box is inserted into the grooves to form a small interference fit, thereby achieving uniform circumferential pressure on the preformed unit tube.

[0052] S1_3. One-time hot pressing and demolding of grouped unit long tubes: Place the complete set of devices obtained in S1_2 into an electric heating drying oven, maintain a pressure of not less than 0.5MPa, set the heating temperature to 80℃ and maintain it for 30 minutes, then set the heating temperature to 130℃ and maintain it for 2 hours. After that, turn off the power and let it cool naturally. Take the complete set of devices out of the electric heating drying oven. Remove the top plate 1 in sequence, take out the packaging box, and separate the upper mold 3_1, 3_2 and the lower mold 4 of the packaging box. First knock out the long strip core (5_4), and then take out the long strip cores 5_1, 5_2, 5_3, 5_6, 5_9, 5_5, 5_7, and 5_8 in sequence. Repeat the above operation to achieve one-time hot pressing and demolding of grouped basic unit long tubes.

[0053] (II) Segmentation and assembly of honeycomb structure:

[0054] S2_1. Molding Unit Slicing: Based on the preset honeycomb structure height, the demolded unit tube 6 is laterally sliced ​​along its length to obtain the basic molding unit, such as... Figure 6 As shown; repeat this operation until the target number of polygonal molding units are obtained.

[0055] S2_2. Molding Unit Bonding and Arrangement: Based on the preset non-periodic ordered topological configuration, the molding units (including some mirror-flipped units) obtained in S2_1 are arranged and spliced ​​tightly from the inside to the outside. Structural adhesive is applied to the joint surface of adjacent units for bonding, and pre-pressing is implemented to fix each molding unit to keep it stable and without loosening. Repeat this operation until a pre-formed structure with a complete topological shape is obtained.

[0056] S2_3. Honeycomb Structure Pressure Molding: The pre-formed structure obtained in S2_2 is placed on the base plate 7 in the assembly pressure molding device, so that its four sides are respectively connected to the L-shaped flexible bonding strip 9, the transverse flexible bonding strip 10, and the longitudinal flexible bonding strip 11; then the transverse movable pressure strip 12 abuts against the transverse flexible bonding strip 10, and the longitudinal movable pressure strip 13 abuts against the longitudinal flexible bonding strip 11; the adjusting bolt 14 on the fixed frame 8 is screwed to drive the transverse movable pressure strip 12 and the longitudinal movable pressure strip 13 to apply pressure synchronously, thereby applying a uniform circumferential clamping force to the splicing unit blocks obtained in S2_2; with the adaptive deformation of all the flexible bonding strips and their full circumferential fit with the pre-formed structure, the pressure on each unit is uniform, which promotes the uniform spread of the adhesive and achieves tight bonding between the units; the applied clamping pressure is controlled between 0.1-0.3MPa according to the size of the honeycomb structure and the viscosity of the structural adhesive. Figure 7 As shown. After 24 hours, loosen bolt 14 and remove the transverse movable pressure strip 12, longitudinal movable pressure strip 13, transverse flexible bonding strip 10, and longitudinal flexible bonding strip 11 in sequence to obtain the preset shaped honeycomb structure.

[0057] If necessary, according to the dimensional design requirements of the honeycomb structure, further machining methods should be used to remove excess material and remove burrs, such as... Figure 9 As shown.

[0058] Example 2.

[0059] A non-periodic ordered fiber-reinforced honeycomb structure, using partial patterns from a Penrose tiling P2 type mosaic as its topological configuration, comprises two basic units: kite-shaped and dart-shaped. The fabrication process remains unchanged; based on Example 1, custom-designed kite-shaped long-tube support core mold 15 (composed of 5 long core strips) and kite-shaped packaging box (including upper mold 16 and lower mold 17) are adapted to the kite-shaped basic units, and dart-shaped long-tube support core mold 18 (composed of 4 long core strips) and dart-shaped packaging box (including upper mold 19 and lower mold 20) are adapted to the dart-shaped basic units. Figure 10 As shown; with other tooling and mold shapes remaining unchanged, the desired aperiodic ordered fiber-reinforced composite honeycomb structure can be obtained, such as Figure 11 As shown.

[0060] The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention shall fall within the protection scope of the present invention.

[0061] For aspects not covered in this invention, such as composite material hot pressing technology, the technology is the same as or can be implemented using existing technologies.

Claims

1. A method for preparing a non-periodic ordered fiber-reinforced honeycomb structure based on long tube forming, slitting, and assembly, characterized in that... This method is particularly well-suited to the unique topological characteristics of aperiodic ordered cellular structures: they are densely packed with basic units of single or multiple geometric shapes and their mirror-flipped units, exhibiting long-range order but lacking global translational symmetry when infinitely extended in a plane. The fabrication process involves two main steps: (a) Forming of a single long tube: S1_1. Unit long tube preforming: First, assemble the long tube support core mold (5), whose cross-sectional shape is consistent with the basic unit. To ensure efficient demolding, the long tube support core mold is obtained by combining multiple long strip cores. Cut the prepreg into rectangular strips, the length of which is equal to the length of the long tube support core mold (5), and the width is determined according to the perimeter of the basic unit and the thickness t of the honeycomb cell wall. Wrap the prepreg strips around the assembled long tube support core mold (5), and the number of wrapping layers is the width of the prepreg strip divided by the perimeter of the long tube support core mold (5). Repeat the above operations to obtain the target number of unit long tube preforms. S1_2. Packaging and pressing of grouped preformed unit tubes: First, apply release agent evenly to the inner surfaces of the upper mold (3) and lower mold (4) of the packaging box; then place the preformed unit tube obtained in S1_1 into the lower mold (4) of the packaging box and achieve tight fit; then cover the preformed unit tube with the upper mold (3) of the packaging box to close the mold, so that the preformed unit tube in the closed cavity can be evenly pressed; then, insert the assembled packaging box into the groove of the base plate (2); repeat the above operation to close the mold of the grouped packaging boxes one by one and insert them into the groove of the base plate (2); finally, place the top plate (1) flat on the fixed grouped packaging boxes according to the groove position, and the packaging and pressing of the grouped preformed unit tubes can be completed. S1_3. One-time hot pressing and demolding of group unit long tubes: Place the complete set of devices obtained in S1_2 into an electric heating drying oven, maintain the pressure at no less than 0.5MPa, set the heating temperature to 80℃ and maintain it for 30 minutes, then set the heating temperature to 130℃ and maintain it for 2 hours, then turn off the power and let it cool naturally, and take the complete set of devices out of the electric heating drying oven; remove the top plate (1) in sequence, take out the packaging box, and separate the upper mold and lower mold of the packaging box; first knock out the long strip core (5_4), then take out the long strip core in sequence, repeat the above operation, and the one-time hot pressing and demolding of group basic unit long tubes can be realized; (II) Segmentation and assembly of honeycomb structure: S2_1. Molding unit cutting: According to the preset honeycomb structure height, the demolded unit tube (6) is cut laterally along its length to obtain the basic molding unit; repeat this operation until the target number of polygonal molding units are obtained. S2_2. Molding Unit Bonding and Arrangement: Based on the preset aperiodic ordered topological configuration, the molding units (including some mirror-flipped units) obtained in S2_1 are arranged and spliced ​​tightly from the inside to the outside. Structural adhesive is applied to the joint surface of adjacent units for bonding, and pre-pressing is implemented to fix each molding unit to keep it stable and without loosening. Repeat this operation until a pre-molded structure with a complete topological morphology is obtained. S2_3. Honeycomb structure pressure molding: The preformed structure obtained in S2_2 is placed on the base plate (7) in the assembled pressure molding device, so that its four sides are connected to the L-shaped flexible bonding strip (9), the transverse flexible bonding strip (10) and the longitudinal flexible bonding strip (11) respectively; then the transverse movable pressure strip (12) abuts against the transverse flexible bonding strip (10) and the longitudinal movable pressure strip (13) abuts against the longitudinal flexible bonding strip (11); the adjusting bolt (14) on the fixed frame (8) is turned to drive the transverse movable pressure strip (12) and the longitudinal movable pressure strip (13) to apply pressure synchronously. Force is applied to the splicing unit blocks obtained in S2_2, thereby applying a uniform circumferential clamping force; with the adaptive deformation of the flexible bonding strips (9, 10, 11) and their full circumferential fit with the preformed structure, the pressure on each unit is uniform, which promotes the uniform spread of the adhesive and achieves tight bonding between the units; the applied clamping pressure is controlled between 0.1-0.3MPa according to the size of the honeycomb structure and the viscosity of the structural adhesive; after 24 hours, the bolts (14) are loosened, the movable pressure strips (12, 13) and the flexible bonding strips (10, 11) are removed, and the preset formed honeycomb structure can be obtained.

2. The preparation method according to claim 1, characterized in that, The geometric shape and size parameters of the cross section of the long tube support core mold (5) are consistent with the shape and internal dimensions of the basic unit in the aperiodic ordered honeycomb structure. In order to achieve efficient demolding, the long tube support core mold (5) is assembled from multiple long strip cores to adapt to the complex geometric shape of the basic unit, such as the thirteen-sided polygon in the Hat tiling topology.

3. The preparation method according to claim 1, characterized in that, The packaging box includes an upper mold (3) and a lower mold (4). The upper mold (3) adopts a split structure, which is composed of two parts to facilitate demolding. The inner contour of the upper and lower molds is consistent with the contour of the matching long tube support core mold (5). The uniform fit gap between the two in the coaxial state is equal to t / 2, which is 1 / 2 of the design size of the cell wall thickness of the honeycomb structure, so as to ensure that the preformed unit long tube is tightly fitted with the long tube support core mold (5) and the inner cavity of the packaging box at the same time.

4. The preparation method according to claim 1, characterized in that, The top plate (1) and bottom plate (2) of the hot pressing forming device are provided with several grooves. The assembled packaging box is inserted into the groove and forms a small interference fit, thereby realizing uniform circumferential pressure on the pre-formed unit long tube.

5. The preparation method according to claim 1, characterized in that, The assembly and pressure forming device includes a base plate (7), a fixed frame (8), movable pressure strips (12, 13), and flexible bonding strips (9, 10, 11); wherein, the flexible bonding strip (9) is L-shaped, and its outer side wall is tightly bonded to the two adjacent inner side walls of the fixed frame (8); the transverse flexible bonding strip (10) and the longitudinal flexible bonding strip (11) are tightly bonded to the transverse movable pressure strip (12) and the longitudinal movable pressure strip (13), respectively; the preformed structure is placed in the space enclosed by the flexible bonding strips, and by tightening the adjusting bolts, the circumferential uniform pressure of the preformed structure is achieved by the synergistic effect of the outer rigid frame and the inner flexible frame; the assembly and pressure forming device adapts to the design requirements of honeycomb structures with different outer edges by relying on the adaptive deformation of the flexible bonding strips.

6. The preparation method according to claim 1, characterized in that, The long tube support core mold (5) is made of polytetrafluoroethylene material to facilitate demolding; the top plate (1), bottom plate (2), upper mold (3), and lower mold (4) of the hot press molding device are all made of metal material to ensure pressure strength and facilitate uniform temperature conduction; the flexible bonding strips (9, 10, 11) of the assembly pressure molding device can be made of silicone or TPU material to utilize their adaptive deformation to fit tightly with the preformed structure circumferentially; the bottom plate (7), fixed frame (8), and movable pressure strips (12, 13) of the assembly pressure molding device are all made of metal material to meet the pressure strength requirements.

7. The preparation method according to claim 1, characterized in that, The topological configuration of the non-periodic ordered fiber reinforced honeycomb structure is derived from a jigsaw puzzle type that has been proven by mathematicians to have non-periodic tessellation characteristics, and a piece of the required pattern is cut out from an infinite tessellation plane, including but not limited to hat tessellation, turtle tessellation, Penrose tessellation type P1, P2, P3.

8. The preparation method according to claim 1, characterized in that, This preparation method has multi-dimensional adjustable adaptability; it can not only prepare honeycomb structures with uniform wall thickness, but also meet the preparation needs of honeycomb structures with varying thickness and size gradient; it can be used not only to prepare non-periodic ordered honeycomb structures, but also to prepare periodic honeycomb structures such as chiral honeycomb and hybrid honeycomb.

9. The preparation method according to claim 1, characterized in that, The preparation method may also include a post-processing step: according to the design requirements of the honeycomb structure size, use mechanical processing methods to remove excess material and polish burrs.

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