Wave-absorbing material based on bionic cobweb structure as well as preparation method and application of wave-absorbing material

Abstract

The invention discloses a wave-absorbing material based on a bionic cobweb structure and a preparation method and application thereof, and belongs to the technical field of functional composite materials. The material comprises a bionic cobweb flat plate, the bionic cobweb flat plate has a cobweb-like structure; the cobweb-like structure is composed of n fan-like areas; meanwhile, the cobweb-like structure is formed by overlapping a framework and second fibers, the framework is formed by arranging n first fibers around the axis in the same plane in the radial direction, no cross-linking point exists between any two first fibers, a plurality of second fibers are arranged on every two adjacent first fibers, and the lengths of the second fibers are sequentially increased in the radial direction; and the second fibers in the bionic cobweb flat plate are non-continuously arranged along the circumferential direction. According to the wave-absorbing material, the periodicity, the structural anisotropy and the node enhancement of a special network structure are combined with the discontinuous conductive network design, and the excellent impedance matching and electromagnetic wave attenuation capacity is achieved at the same time.

Description

TECHNICAL FIELD

[0001] The present application relates to a wave-absorbing material based on a biomimetic spider web structure and a preparation method and application thereof, and is particularly suitable for the field of electromagnetic wave absorption and shielding, and belongs to the technical field of functional composites. BACKGROUND

[0002] Electromagnetic wave absorbing materials play a crucial role in the fields of microwave communication, electromagnetic compatibility (EMC) of electronic devices, electromagnetic radiation protection, and military stealth technology. An ideal wave-absorbing material should have the characteristics of "thin, light, wide, and strong", i.e., thin thickness, light mass, wide absorption frequency band, and strong absorption capacity.

[0003] Currently, common wave-absorbing materials mainly include magnetic absorbing materials (such as ferrite) and dielectric absorbing materials (such as carbon-based materials, conductive polymers, etc.). Magnetic absorbing materials have excellent absorption performance at low frequencies, but have the disadvantages of high density, poor temperature resistance, and poor high-frequency performance. Dielectric absorbing materials usually have low density, and their absorption performance is highly dependent on the electrical conductivity and dielectric constant of the material itself, often having the problem of difficulty in impedance matching, i.e., single-component materials are difficult to simultaneously satisfy the conditions of strong attenuation characteristics and good incident impedance matching, resulting in a narrow effective absorption bandwidth.

[0004] In order to overcome the limitations of single-material systems, multi-level and multi-structure design has become a key technical approach to improving the performance of wave-absorbing materials. Inspired by the exquisite structures in nature, biomimetic design has been widely applied in the field of materials science.

[0005] There have been attempts in the prior art to use biomimetic structures for wave-absorbing materials. For example, Chinese Patent Publication No. CN119674562A discloses a "heterogeneous honeycomb wave-absorbing structure" composed of multiple hexagonal honeycomb units including multiple different electromagnetic materials. However, it mainly targets radial incidence in the direction of electromagnetic wave incidence, and has limited ability to capture spatial multi-dimensional incident waves. These existing technologies based on biomimetic network structures are difficult to achieve high-efficiency wide-band absorption at low filling levels.

[0006] Therefore, it is an urgent problem in the field to develop a new type of lightweight wide-band wave-absorbing material that can accurately simulate the periodic structural characteristics of natural spider webs and improve the electromagnetic wave characteristics to achieve excellent impedance matching and electromagnetic wave attenuation capability. SUMMARY

[0007] In view of the problems that the impedance matching and the attenuation ability of the traditional single wave-absorbing material are difficult to coordinate, the traditional magnetic wave-absorbing material has large density and is not resistant to high temperature, the existing bionic wave-absorbing material has unreasonable structure design and cannot simultaneously realize efficient electromagnetic wave capturing and dissipating, and the wave-absorbing performance is limited, the first object of the present application is to provide a wave-absorbing material based on a bionic spider web structure, which can simultaneously realize excellent impedance matching and electromagnetic wave attenuation ability by using the periodicity, structural anisotropy and node enhancement of the special network structure of the bionic spider web structure in combination with a discontinuous conductive network design.

[0008] The second object of the present application is to provide a preparation method of the wave-absorbing material based on the bionic spider web structure, which has the advantages of simple process and strong controllability.

[0009] The third object of the present application is to provide an application of the wave-absorbing material based on the bionic spider web structure.

[0010] In order to realize the above technical objects, the present application provides a wave-absorbing material based on a bionic spider web structure, which comprises a bionic spider web plate. The bionic spider web plate has a spider web-like structure. The spider web-like structure is composed of n fan-like regions. Meanwhile, the spider web-like structure comprises a framework and a second fiber lap joint. The framework is composed of n first fibers arranged in the same plane in a radial direction around an axis. There is no crosslinking point between any two first fibers. A plurality of second fibers are arranged on the adjacent two first fibers. The length of the second fiber increases in the radial direction. The second fiber in the bionic spider web plate is arranged discontinuously in the circumferential direction. n is a positive integer greater than or equal to 4.

[0011] In the wave-absorbing material of the present application, the framework provides the main support structure for the spider web, and the second fiber forms a bionic spider web-like capturing network structure. However, the natural spider web structure in nature is a continuous network structure. If it is directly used as a wave-absorbing material for electromagnetic wave attenuation, a continuous conductive network is easily formed, which greatly reduces the impedance matching ability of the spider web structure. The present application adopts the discontinuous arrangement of the second fiber in the circumferential direction according to the properties and attenuation law of electromagnetic waves. Compared with the natural spider web, there is no crosslinking point between any two first fibers, which avoids the formation of a conductive network and significantly improves the impedance matching ability of the spider web structure. The design that the length of the second fiber increases in the radial direction can form a large capturing network surface, so that the electromagnetic wave can be more efficiently absorbed and transmitted.

[0012] The fan-like region of the present application refers to the first fiber constituting the region diverging outward from the center point. The outer edge line of the fan-like region can be arc-shaped, straight, broken, spiral-shaped or wave-shaped.

[0013] The first fiber and the second fiber of the present application can adopt materials used in the field of wave-absorbing materials according to actual conditions, including but not limited to carbon fiber, silicon carbide fiber, silicon nitride fiber, SiCN fiber, alumina fiber, SiBCN fiber. In the spiderweb-like structure of the present application, the fan-like regions can be equal in area or designed to be non-equal in area according to different electromagnetic wave properties; in addition, n can be an odd number or an even number. However, when n is an even number, the capture network structure can be maximized to form a staggered gap. At the same time, the number of second fibers arranged in each fan-like region of the present application can be designed to be the same or different according to the actual required area of the capture network. In the present application, n is a positive integer greater than or equal to 4, such as 4, 5, 8, 12, 13, 50, 100, etc.

[0014] The flat plate used in the present application includes but is not limited to a PVC flat plate.

[0015] As a preferred scheme, a circular hole is used at the center of the spiderweb-like structure to avoid cross-linking between any two first fibers, and the radius r of the circular hole is greater than 1 mm. Further, the radius r of the circular hole is 8-12 mm. The circular hole can avoid the formation of a conductive network in the skeleton, thereby reducing the overall conductivity and improving the impedance matching degree of the bionic spiderweb structure with air.

[0016] As a preferred scheme, the second fibers in any adjacent fan-like regions in the bionic spiderweb flat plate are staggered. The placement of the second fibers in each individual fan-like region in the present application can adopt parallel arrangement or non-parallel arrangement, and when parallel arrangement is adopted, the distance between the two adjacent second fibers can be equal or unequal according to actual operation, as long as the second fibers in the adjacent fan-like regions are not connected. Further, the placement of the second fibers in each individual fan-like region in the present application is equal-interval parallel arrangement.

[0017] As a preferred scheme, when n is an even number, the second fibers of the odd-numbered fan-like regions are arranged in a ring, and the second fibers of the even-numbered fan-like regions are also arranged in a ring, and the second fibers of the adjacent two fan-like regions are not arranged in a ring. When the above design is adopted, the convenience of the preparation method can be greatly improved, and at the same time, the best impedance attenuation and staggered pores can be achieved.

[0018] As a preferred scheme, the spiderweb-like structure is composed of n equal-angle fan-like regions.

[0019] As a preferred embodiment, both the first and second fibers are selected from at least one of silicon carbide fibers and carbon fibers, and their outer surfaces are coated with epoxy resin. Silicon carbide fibers are semiconductor materials with a high electrical loss tangent; while carbon fibers are conductor materials. Further combining these two fiber materials is more conducive to achieving the wave absorption performance of the spiderweb structure. Epoxy resin is a typical dielectric material with extremely poor conductivity. Its main function is to dilute the overall dielectric constant of the silicon carbide or carbon fibers, while also providing some mechanical support and protection for the brittle fibers, thus endowing the biomimetic spiderweb wave-absorbing material of this invention with the necessary mechanical strength and stiffness.

[0020] As a preferred embodiment, the first fiber is composed of silicon carbide fibers coated with epoxy resin; the second fiber is composed of carbon fibers coated with epoxy resin. When the preferred selection and combination of the first and second fibers of this invention are used, efficient energy absorption and transfer can be achieved. Specifically, this invention utilizes the semiconductor properties of silicon carbide fibers to achieve good impedance matching with free space, while also incorporating some dielectric loss; it utilizes the strong conductivity and dielectric constant of carbon fibers to generate strong conductivity loss and polarization relaxation loss, and provides good attenuation capability through eddy current loss between parallel carbon fibers, significantly improving the wave absorption performance of the material. During the wave absorption process, electromagnetic waves easily enter the interior of the material from the low-impedance silicon carbide skeleton layer and are efficiently dissipated by the high-loss carbon fiber trapping network, forming a continuous impedance gradient within the material, thus simultaneously resolving the contradiction between high absorption and low reflection. Furthermore, the first fiber uses high-modulus silicon carbide fibers as the skeleton, ensuring the overall stability and mechanical strength of the spiderweb structure. In addition, its excellent thermal stability and oxidation resistance ensure the reliability of the material. The second fiber uses high-strength, high-toughness carbon fibers, effectively achieving the weavability and durability of the structure.

[0021] Furthermore, when the first fiber constituting the skeleton is silicon carbide fiber, the fiber width is 0.3~0.5mm and the thickness is 0.1~0.15mm; when the second fiber is carbon fiber, the fiber width is 2~mm and the thickness is 0.2~0.3mm.

[0022] As a preferred embodiment, the microwave absorbing material further includes a cross-shaped plate; the cross-shaped plate is composed of a first fiber and a second fiber arranged in a cross-shaped pattern; wherein the cross-shaped plate is stacked with a biomimetic spider web plate. When the biomimetic spider web plate and the cross-shaped plate of the present invention are used in combination, the microwave absorption performance of the material can be further improved.

[0023] Furthermore, when cross-shaped plates and biomimetic spider web plates are stacked together, multiple layers of cross-shaped plates can be used. The biomimetic spider web plate can be located above the cross-shaped plates, in the middle of the multiple layers of cross-shaped plates, or below the cross-shaped plates.

[0024] As a preferred embodiment, the biomimetic spiderweb plate is positioned above the cross-shaped plate. Experiments have shown that when the biomimetic spiderweb plate is positioned above the cross-shaped plate, it exhibits optimal reflection loss capability. This is mainly because, on the one hand, the single-layer biomimetic spiderweb structure is closer to the air impedance, allowing more electromagnetic waves to enter the structure's interior; on the other hand, the increased thickness increases the number of reflections of electromagnetic waves within the structure, thereby improving the electromagnetic wave absorption capability.

[0025] This invention also provides a method for preparing a wave-absorbing material based on a biomimetic spider web structure. This method involves cutting the first and second fibers to designed lengths, then assembling them on a flat plate using an adhesive to create a designed spider web-like structure. It should be noted that this is only a preferred method of this invention; in actual operation, the appropriate method can be selected based on the specific circumstances.

[0026] During assembly, the first fiber can be fixed first, and then the second fiber can be glued to the two adjacent first fibers.

[0027] As a preferred option, the adhesive includes, but is not limited to, commercially available 502 glue; other adhesives commonly used in microwave absorbing materials may also be used.

[0028] In practice, computer software such as Photoshop can be used to print out the design drawing and paste it onto a flat plate. Then, the first and second fibers are assembled according to the design drawing.

[0029] Finally, this invention also provides an application of a wave-absorbing material based on a biomimetic spider web structure, which is applied to the field of electromagnetic wave absorption and shielding. The unique spider web structure design of this invention has excellent broadband absorption performance and can minimize the direct reflection of electromagnetic waves.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) Traditional absorbing materials cannot simultaneously achieve impedance matching and attenuation capabilities, resulting in limited absorption performance. However, this invention, based on the periodicity, structural anisotropy, and node reinforcement of a biomimetic spider web structure combined with a discontinuous conductive network design, can achieve efficient energy absorption and transfer, significantly improving the material's absorption performance. Furthermore, by combining it with other materials, the overall absorption performance of the material can be significantly enhanced, demonstrating enormous application potential and competitiveness in the field of electromagnetic wave absorption and shielding.

[0032] (2) In a further optimized scheme, the present invention uses an innovative material combination of silicon carbide fiber skeleton and carbon fiber trapping mesh to form a continuous impedance gradient inside the material, making it easy for electromagnetic waves to enter the material from the low-impedance silicon carbide skeleton layer and be efficiently dissipated by the high-loss carbon fiber mesh, thus simultaneously solving the contradiction between high absorption and low reflection. In addition, the use of high-modulus silicon carbide fiber as skeleton ensures the overall stability and mechanical strength of the structure; at the same time, the use of high-strength and high-toughness carbon fiber as trapping mesh realizes the weavability and durability of the structure.

[0033] (3) In view of the properties and attenuation law of electromagnetic waves, the present invention adopts the discontinuous arrangement of the second fiber along the circumferential direction to avoid the formation of conductive network and significantly improve the impedance matching capability of the spider web structure.

[0034] (4) The biomimetic spider web structure of the present invention is highly adjustable. By precisely controlling the structural parameters such as the diameter, spacing and arrangement angle of the fibers, it can achieve highly flexible customized design for specific application scenarios.

[0035] (5) The preparation method of the present invention is simple and the raw materials are readily available, and it has the potential for industrial production. Attached Figure Description

[0036] Figure 1 This is a design drawing of a wave-absorbing material based on a biomimetic spider web structure in Example 1.

[0037] Figure 2 This is a macroscopic diagram of a wave-absorbing material based on a biomimetic spider web structure in Example 1.

[0038] Figure 3 This is a reflection loss curve of a wave-absorbing material based on a single-layer biomimetic spider web structure in Example 1.

[0039] Figure 4 The images show macroscopic views of fiber cross-shaped absorbing flat panels of different specifications in Example 2, where (a) is panel 2; (b) is panel 3; (c) is panel 4; (d) is panel 5; and (e) is panel 6.

[0040] Figure 5 The graph shows the reflection loss curves of single-layer fiber cross-shaped absorbing plates of different specifications in Example 2.

[0041] Figure 6 The graph shows the comparison of reflection loss of a single-layer fiber cross-shaped plate before and after adding the biomimetic spider web structure in Example 3.

[0042] Figure 7The graph shows the comparison of reflection loss of the double-layer fiber cross-shaped plate before and after adding the biomimetic spider web structure in Example 4; "123" represents the arrangement of the fiber absorbing plates from top to bottom as plate 1, plate 2, and plate 3.

[0043] Figure 8 The graph shows the comparison of reflection loss of the five-layer fiber cross-shaped plate before and after adding the biomimetic spider web structure in Example 5.

[0044] Figure 9 This is a graph comparing the reflection loss before and after the positions of the biomimetic spider web plate and the fiber cross-shaped plate were interchanged in Example 6.

[0045] Figure 10 The graph shows the reflection loss curve of the biomimetic spider web plate prepared in Example 7.

[0046] Figure 11 This is a comparison chart of the reflection loss curves of the double-layer structure in Comparative Example 1, which includes a biomimetic spider web plate and one without.

[0047] Figure 12 The images show the design drawing (a) and the imitation drawing (b) of the spiral spider web plate obtained by imitating the natural spider web structure of Comparative Example 2. Among them, Figures 4-11 In the figure, plate 1 is the biomimetic spider web structure absorbing material prepared in Example 1; taking 123456 as an example, it represents that the absorbing materials are plate 1, plate 2, plate 3, plate 4, plate 5 and plate 6 stacked from top to bottom, and the remaining numbers are similar. Detailed Implementation

[0048] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0049] Example 1

[0050] (1) Commercial carbon fiber (Toray T300, 6 K) and silicon carbide fiber (Zeralon RAF, 0.5 K) were used as raw materials. The carbon fiber was 2 mm wide and 0.2 mm thick. The silicon carbide fiber was 0.5 mm wide and 0.1 mm thick. The fiber was coated with a layer of E-44 epoxy resin and dried in air at room temperature for 24 h.

[0051] (2) According to Figure 1In the designed spiderweb-like structure, the lengths of the first and second fibers are determined by cutting the E-44 epoxy resin-coated silicon carbide fibers into longer fiber segments (ranging from 86 to 110 mm) and the E-44 epoxy resin-coated carbon fibers into shorter fiber segments (ranging from 5 to 33 mm). In the spiderweb-like structure, n is 20. A circular through-hole with a radius of 8 mm is used at the center to prevent cross-linking between any two first fibers. The skeleton is composed of 20 first fibers arranged radially around the axis in the same plane, forming 20 fan-shaped regions of equal area. The second fibers in the odd-numbered fan-shaped regions are arranged in the same ring, and the second fibers in the even-numbered fan-shaped regions are arranged in the same ring. Adjacent fan-shaped regions are not arranged in the same ring to achieve the staggered arrangement of the second fibers in any adjacent fan-shaped regions of the biomimetic spiderweb plate. The first fiber is silicon carbide fiber wrapped in E-44 epoxy resin, and the second fiber is carbon fiber wrapped in E-44 epoxy resin. The length of the second fiber on adjacent first fibers increases sequentially in the radial direction. The second fibers in a single fan-shaped region are arranged in parallel with a spacing of 7~10 mm.

[0052] (3) Attach the first fiber to the PVC board according to the design drawing and bond it with a small amount of 502 glue;

[0053] (4) Attach the second fiber to the PVC board according to the design drawing, with both ends located above the adjacent silicon carbide fiber section of the first fiber, and use a small amount of 502 glue to bond the overlapping parts of the two fibers.

[0054] (5) Drying in air at room temperature for 24 hours yields a biomimetic spider web plate with a thickness of 1.2 mm;

[0055] (6) Test the reflection loss of a single-layer biomimetic spider web plate in the range of 2 to 18 GHz.

[0056] The final macroscopic morphology and reflection loss of the biomimetic spider web plate are as follows: Figure 2 , Figure 3 As shown.

[0057] Example 2

[0058] In this embodiment, plate No. 1 is the biomimetic spider web plate prepared in Example 1. Additionally, fiber cross-shaped plates (plates No. 2 to No. 6) are also prepared. The plate dimensions of plates No. 2 to No. 6 are all 180mm × 180mm, and they are composed of M horizontally placed fibers and N vertically placed fibers, respectively.

[0059] Preparation of Plate No. 2: Silicon carbide fibers and carbon fibers coated with E-44 epoxy resin from Step 1 of Example 1 were bonded together in a cross-shaped pattern using plates similar to those used in the biomimetic spiderweb plate. The processing method was the same, using 502 glue to bond the nodes. All plates used were PVC boards. The resulting cross-shaped mesh plate, as shown... Figure 4 As shown in (a), the coarse fiber is carbon fiber, the fine fiber is silicon carbide fiber, M is 17, and N is 17.

[0060] Preparation of Plate No. 3: Silicon carbide fibers and carbon fibers coated with E-44 epoxy resin from Step 1 of Example 1 were bonded together in a cross-shaped pattern using plates of the same type as the biomimetic spiderweb plate. The processing method was the same, using 502 glue to bond the nodes. All plates used were PVC plates. The resulting cross-shaped mesh plate, as shown... Figure 4 As shown in (b), the coarse fiber is carbon fiber, the fine fiber is silicon carbide fiber, M is 17, and N is 17.

[0061] Preparation of Plate No. 4: Silicon carbide fibers coated with E-44 epoxy resin from step 1 of Example 1 were bonded to a biomimetic spiderweb-like plate in a cross-shaped pattern using the same treatment method, employing 502 glue to bond the nodes. All plates used were PVC boards. The resulting cross-shaped mesh plate, as shown... Figure 4 As shown in (c), M is 9 and N is 9.

[0062] Preparation of Plate No. 5: Silicon carbide fibers coated with E-44 epoxy resin from Step 1 of Example 1 were bonded to a biomimetic spiderweb-like plate in a cross-shaped pattern using the same treatment method, employing 502 glue for joint bonding. All plates used were PVC boards. The resulting cross-shaped mesh plate, as shown... Figure 4 As shown in (d), M is 17 and N is 17.

[0063] Preparation of Plate No. 6: The carbon fiber coated with E-44 epoxy resin from step 1 of Example 1 was bonded to a biomimetic spiderweb-like plate in a cross-shaped pattern using the same treatment method, employing 502 glue to bond the nodes. All plates used were PVC boards. The resulting cross-shaped mesh plate, as shown... Figure 4 As shown in (e), M is 9 and N is 9.

[0064] The reflection loss of single-layer fiberboards (boards 1 through 6) was tested at 2–18 GHz, and their reflection loss curves are shown below. Figure 5 As shown.

[0065] Example 3

[0066] Plates 2 through 6 were placed below the biomimetic spider web flat plate No. 1 prepared in Example 2, resulting in double-layer plate structures of 12, 13, 14, 15, and 16.

[0067] Changes in reflection loss before and after adding a biomimetic spider web plate, such as Figure 6 As shown.

[0068] Example 4

[0069] Place a double-layer fiber cross plate composed of plates 2 and 3 below the biomimetic spider web plate No. 1 prepared in Example 2 to obtain a three-layer plate structure of 123 (representing the fiber absorbing plate arrangement order from top to bottom as plate 1, plate 2, plate 3, and the remaining numbering follows the same pattern) and 132.

[0070] Changes in reflection loss before and after adding a biomimetic spider web plate, such as Figure 7 As shown.

[0071] Example 5

[0072] Five-layer fiber cross-shaped plates composed of plates 2 to 6 were placed below the biomimetic spider web flat plate No. 1 prepared in Example 2 to obtain a six-layer plate structure of 123456, 132456, 142356, 152346, and 162345.

[0073] Test its reflection loss curve, such as Figure 8 As shown.

[0074] Example 6

[0075] Placing plate No. 2 on top of plate No. 1 of the biomimetic spider web flat plate prepared in Example 2 results in a 21-layer double-plate structure.

[0076] Test the reflection loss from 2 to 18 GHz, such as Figure 9 As shown.

[0077] Example 7

[0078] The only difference between this embodiment and Embodiment 1 is that the first fiber is replaced with carbon fiber coated with E-44 epoxy resin, and the second fiber is replaced with silicon carbide fiber coated with E-44 epoxy resin. The remaining steps and conditions are the same as in Embodiment 1.

[0079] The tested biomimetic spider web flat panel exhibits reflection loss in the 2–18 GHz range, as shown in the figure. Figure 10 As shown.

[0080] Comparative Example 1

[0081] The plates No. 2 and No. 3 prepared in Example 2 were stacked to obtain double-layer plate structures No. 23 and No. 32, respectively. Reflection loss tests were conducted on these structures and the double-layer plate structure in Example 3 at 2–18 GHz. The results are as follows: Figure 11 As shown.

[0082] Comparative Example 2

[0083] Compared to Example 1, the only difference in this comparative example is that the placement of the first and second fibers completely mimics the structure of a natural spider web, as shown in the design diagram. Figure 12 The processing method is the same, and 502 glue is used to bond the nodes; the flat plates used are all PVC boards, and the model is the same as in Example 1, to obtain a spiral spider web flat plate.

[0084] The test results of the single-layer board at 2~18GHz show that its reflection loss capability is lower than that of Example 1.

[0085] from Figure 5 It can be seen that the single-layer spider web flat panel has better reflection loss capability than the fiber cross structure in the 2-18GHz range.

[0086] from Figure 6 As can be seen, the single-layer fiber cross-shaped plate, with a thickness of 1.2 mm, has no qualified bandwidth. The double-layer structure with added biomimetic spider web plate, with a thickness of 2.4 mm, has a large qualified bandwidth (RL < -10dB). The qualified bandwidth of serial number 12 is 6.72 GHz; the qualified bandwidth of serial number 13 is 5.36 GHz; the qualified bandwidth of serial number 14 is 4.68 GHz; the qualified bandwidth of serial number 15 is 8.00 GHz; and the qualified bandwidth of serial number 16 is 5.57 GHz.

[0087] from Figure 7 It can be seen that the double-layer fiber cross-shaped plate does not have a qualified bandwidth. After adding the biomimetic spider web plate, the thickness is 3.6 mm, and a larger qualified bandwidth appears. The qualified bandwidth of serial number 123 is 10.03 GHz, and the maximum reflection loss value reaches -24.27 dB at 13.20 GHz; the qualified bandwidth of serial number 132 is 8.97 GHz, and the maximum reflection loss value reaches -20.24 dB at 10.95 GHz.

[0088] from Figure 8It can be seen that the five-layer fiber cross-shaped plate has a relatively small bandwidth. After adding the biomimetic spider web plate, the thickness is 7.2 mm, and the bandwidth increases significantly. The qualified bandwidth of serial number 123456 is 16 GHz, and the maximum reflection loss value reaches -24.90dB at 6.52 GHz; the qualified bandwidth of serial number 132456 is 16 GHz, and the maximum reflection loss value reaches -42.78dB at 8.60 GHz; the qualified bandwidth of serial number 142356 is 16 GHz, and the maximum reflection loss value reaches -27.61dB at 16.09 GHz; the qualified bandwidth of serial number 152346 is 16 GHz, and the maximum reflection loss value reaches -17.43dB at 16.38 GHz; the qualified bandwidth of serial number 162345 is 16 GHz, and the maximum reflection loss value reaches -57.91dB at 11.41 GHz.

[0089] from Figure 9 It can be seen that the reflection loss of the upper double-layer structure of the biomimetic spider web plate is significantly better than that of the lower double-layer structure.

[0090] from Figure 10 It can be seen that the reflection loss of the double-layer structure containing the biomimetic spider web plate is significantly better than that of the double-layer structure without the biomimetic spider web plate.

Claims

1. A wave-absorbing material based on a biomimetic spider web structure, characterized in that: The invention includes a biomimetic spider web plate; the biomimetic spider web plate has a spider web-like structure; the spider web-like structure is composed of n fan-shaped regions; the spider web-like structure is composed of a skeleton and second fibers overlapping, wherein the skeleton is composed of n first fibers arranged radially around an axis in the same plane, and there are no cross-linking points between any two first fibers, and several second fibers are provided on two adjacent first fibers, and the length of the second fibers increases sequentially along the radial direction; The second fiber in the biomimetic spider web plate is discontinuously arranged circumferentially. Where n is a positive integer greater than or equal to 4.

2. The wave-absorbing material based on a biomimetic spider web structure according to claim 1, characterized in that: The second fiber is misaligned in any adjacent fan-shaped region of the biomimetic spider web plate.

3. A wave-absorbing material based on a biomimetic spider web structure according to claim 1 or 2, characterized in that: When n is even, the second fibers of the fan-shaped regions of odd-numbered terms are arranged in the same ring, and the second fibers of the fan-shaped regions of even-numbered terms are also arranged in the same ring, and two adjacent fan-shaped regions are not arranged in the same ring.

4. The wave-absorbing material based on a biomimetic spider web structure according to claim 3, characterized in that: The spiderweb-like structure consists of n fan-shaped regions of equal area.

5. The wave-absorbing material based on a biomimetic spider web structure according to claim 1, characterized in that: The first fiber and the second fiber are both selected from at least one of silicon carbide fiber and carbon fiber, and their outer surfaces are coated with epoxy resin.

6. The wave-absorbing material based on a biomimetic spider web structure according to claim 5, characterized in that: The first fiber is composed of silicon carbide fibers coated with epoxy resin; the second fiber is composed of carbon fibers coated with epoxy resin.

7. The wave-absorbing material based on a biomimetic spider web structure according to claim 6, characterized in that: The absorbing material also includes a cross-shaped plate; the cross-shaped plate is composed of a first fiber and a second fiber arranged in a cross shape; wherein the cross-shaped plate is stacked with a biomimetic spider web plate.

8. The wave-absorbing material based on a biomimetic spider web structure according to claim 7, characterized in that: The biomimetic spider web plate is located above the cross-shaped plate.

9. A method for preparing a wave-absorbing material based on a biomimetic spider web structure as described in any one of claims 1 to 8, characterized in that: After cutting the first and second fibers to the designed lengths, they are assembled on a flat plate using an adhesive according to the designed spiderweb-like structure.

10. The application of a wave-absorbing material based on a biomimetic spider web structure as described in any one of claims 1 to 8, characterized in that: It is used in the field of electromagnetic wave absorption and shielding.

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