Preparation method of flexible molybdenum disulfide fiber fabric wave-absorbing superstructure and composite material and application thereof

Abstract

The application discloses a preparation method of a flexible molybdenum disulfide fiber fabric wave-absorbing superstructure and application of a composite material thereof. The preparation of the flexible molybdenum disulfide fiber fabric wave-absorbing superstructure is realized through a resin mask assisted etching method. The molybdenum disulfide fiber fabric wave-absorbing composite material of the application realizes the wave-absorbing function on the basis of retaining the characteristics of the traditional fiber composite material, such as light weight and excellent mechanical properties. The molybdenum disulfide fiber fabric and the molybdenum disulfide fiber fabric wave-absorbing superstructure are homogenous and isomorphic with the traditional fiber, and therefore have good compatibility with the resin-based composite material process and system. Based on the layering process, compared with other wave-absorbing materials, the function integration is more conducive to be realized. The introduction of the wave-transparent window is realized through selective etching, and meanwhile the continuity of the fiber base is not affected, and therefore the mechanical properties of the fiber reinforced resin composite material are maintained. The molybdenum disulfide fiber has good flexibility, and therefore has good special-shaped structure adaptability. The wave-absorbing performance is further improved through partition design, and meanwhile the mechanical properties of the fiber reinforced composite material are not affected.

Description

Technical Field

[0001] This invention belongs to the field of microwave absorbing stealth materials, specifically relating to a method for preparing a flexible montmorillonite fiber fabric microwave absorbing superstructure and its composite materials and applications. Background Technology

[0002] Existing microwave absorbing materials include the following categories, each with its own drawbacks:

[0003] (1) Magnetic absorbing materials

[0004] Magnetic absorbing materials mainly refer to those containing magnetic metallic elements such as Fe, Co, and Ni. Common examples include Fe, Co, and Ni magnetic metal powders, magnetic oxides, polycrystalline metal fibers, magnetic nanospheres, and ferrite ceramic materials. These materials generally exhibit high permeability in the microwave frequency band and possess both magnetic and dielectric loss mechanisms for electromagnetic waves, thus making them widely used in the preparation of absorbing materials. The advantage of magnetic absorbing materials is their excellent absorption performance. However, for high-speed aerospace vehicles, their disadvantage lies in the Curie temperature, making them difficult to use in high-temperature environments. Furthermore, achieving ideal absorption effects requires significant thickness, hindering lightweight design and limiting their application in the aerospace field.

[0005] (2) Ceramic-based microwave absorbing materials

[0006] Ceramic-based microwave absorbing materials are mainly represented by SiC ceramics and their composites, with ferrite ceramics also being a type. Certain parts of aircraft and weapons, such as nose cones, engine air intakes, and nozzles, require high-temperature resistance. To meet the stealth requirements of these special components, high-temperature microwave absorbing materials, such as ceramic spheres, ceramic fibers, and ceramic matrix composites, are being actively developed both domestically and internationally. Currently reported ceramic microwave absorbing materials mainly include SiC, SiC / SiBCN, Si3N4, Al2O3, and Ti3SiC2. Among these, SiC nanomaterials and their ceramic composites have been the most extensively studied. The advantages of ceramic-based microwave absorbing materials are high strength, high hardness, good oxidation resistance, and high thermal stability. However, their disadvantages are also obvious: their dielectric properties and microwave absorption performance are relatively weak, and it is difficult to achieve lightweight design.

[0007] (3) Structural absorbing metamaterials

[0008] Magnetic and ceramic-based absorbing materials have gradually faded from use due to their high density, heavy weight, narrow absorption peaks, and weak absorption capabilities. In contrast, structural absorbing metastructures, with their lightweight, wide bandwidth, and strong absorption capabilities, are gradually replacing traditional coating-type absorbing materials and have become the focus of research in this field both domestically and internationally. In recent years, widely reported structural metamaterials include frequency-selective surfaces (FSS), electromagnetic band-gap structures (EBG), high-impedance surfaces (HIS), artificial magnetic conductors (AMC), and phase-gradient metasurfaces (PGM). These metamaterials can achieve precise manipulation of electromagnetic waves through specialized structural designs. Absorbing materials based on metamaterials are easy to achieve in terms of thinness, lightness, bandwidth, and strength, and have broad application prospects in the military field. However, most of the microwave absorbing metamaterials currently being studied use metal patches as the resistive layer, which often lacks flexibility and makes it difficult to adapt to irregular structures.

[0009] While traditional fiber-reinforced composite materials exhibit excellent mechanical properties, lightweighting, and corrosion resistance, they still have significant shortcomings in high-temperature resistance, interface stability, and electromagnetic stealth capabilities, making it difficult to meet the requirements of future advanced equipment.

[0010] Therefore, the preparation of fiber-reinforced resin-based composite materials with wave-absorbing and stealth properties that are adapted to irregular structures is an urgent problem to be solved. Summary of the Invention

[0011] Addressing the problems of existing technologies: (1) Existing microwave absorbing structures increase the weight and thickness of the overall structure, making them unsuitable for the long-term stable service requirements of aerospace equipment; (2) They lack flexibility and cannot be adapted to irregularly shaped structural components. Based on the advantages of lightweight fiber-reinforced resin-based composite materials, this invention develops a flexible montmorillonite fiber fabric superstructure preparation strategy compatible with resin-based composite processes and systems. The montmorillonite fiber fabric superstructure is prepared by etching the surface of CVD-grown montmorillonite fiber fabric, and further combined with resin to endow traditional fiber-reinforced resin-based composite materials with microwave absorbing functions. In addition, the montmorillonite fiber fabric microwave absorbing superstructure layer and the montmorillonite fiber fabric heating layer can be integrated to achieve the integration of microwave absorption and electric heating functions. Furthermore, based on the flexibility of montmorillonite fabric, its surface designability and continuity are utilized to develop a partitioned microwave absorbing structure adapted to irregularly shaped curved surfaces.

[0012] This invention first provides a method for fabricating flexible montmorillonite fiber fabric microwave absorbing superstructures using a resin mask-assisted etching method compatible with composite systems.

[0013] The method for preparing a flexible styrene fiber fabric microwave absorbing superstructure provided by the present invention includes the following steps:

[0014] 1) Based on the pattern design and structural parameters of the montmorillonite fiber fabric superstructure, a pattern mold is manufactured, and the obtained pattern mold is applied to the montmorillonite fiber fabric;

[0015] 2) Apply the resin film to the montmorillonite fiber fabric covered with the pattern mold, impregnate it, so that the resin penetrates vertically into the montmorillonite fiber fabric and conformally covers the montmorillonite fibers in the area covered by the resin film.

[0016] 3) Remove the pattern mold and the resin film on it. The resin film in the patterned area remains on the montmorillonite fiber fabric in a patterned manner to obtain a montmorillonite fiber fabric with a patterned resin film attached.

[0017] Alternatively, skipping steps 1)-3), directly attach the resin film based on the pattern design and structural parameters of the montmorillon fiber fabric superstructure to the montmorillon fiber fabric, impregnate it, and obtain the montmorillon fiber fabric with the patterned resin film attached.

[0018] 4) Reactive ion etching process: Etching the graphene on the surface of the montmorillonite fiber fabric in the area not covered by the patterned resin film to obtain the patterned montmorillonite fiber fabric microwave absorbing superstructure.

[0019] In step 1) of the above method, the pattern mold can be a metal mold, a paper mold, etc.; the function of the pattern mold includes covering areas that do not need to be covered with adhesive film, positioning, etc.

[0020] The montmorillonite fiber fabric includes montmorillonite glass fiber fabric, montmorillonite quartz fiber fabric, and montmorillonite alumina fiber fabric, and its weaving method can be plain weave, twill weave, or satin weave.

[0021] The graphene fiber fabric can be prepared by a method including the following steps: growing graphene on the surface of the fiber fabric using chemical vapor deposition to obtain the graphene fiber fabric.

[0022] Before growing graphene, the fiber fabric is first treated to remove the sizing agent, i.e., to remove the adhesive.

[0023] The desizing agent is obtained by heat treatment, that is, heating the fibrous fabric in an air or oxygen atmosphere, the heating temperature can be 800-900℃, and the time can be 3-5 h;

[0024] The chemical vapor deposition uses gases such as ethylene, acetylene, and methane as carbon sources, with a growth temperature of 900-1100 ℃ and a growth time of 0.5-48 h.

[0025] The fiber fabric includes glass fiber fabric, quartz fiber fabric, and alumina fiber fabric (alumina content 72%-99%), and its weaving method can be plain weave, twill weave, or satin weave; the thickness of the fiber fabric can be 0.1-0.3 mm.

[0026] The resin film is made of epoxy resin;

[0027] The impregnation operation involves placing the resin-coated montmorillonite fiber fabric into a vacuum bag, evacuating it to (-850)-(-1000) mbar, and holding it at a temperature of 50-85℃ for 20-60 min.

[0028] In step 4) of the above method, the reactive ion etching process involves bombarding graphene with oxygen plasma to break the carbon-carbon bonds in the graphene. The carbon atoms react with oxygen atoms to generate carbon monoxide (CO) and carbon dioxide (CO2) gases, thereby achieving the etching of the graphene.

[0029] The reactive ion etching process uses one or both of the following oxygen sources: air and oxygen. The oxygen-containing reactive species (oxygen plasma) can be adjusted by the ratio of the oxygen source to the inert gas source (helium or argon). The power is 30-100% of the instrument's set value, and the processing time can be 10 min-120 min.

[0030] The patterned montmorillonite fiber fabric microwave absorbing superstructure prepared by the above method also falls within the protection scope of this invention.

[0031] The patterned graphene fiber fabric microwave absorbing superstructure comprises: a fiber fabric, at least one array patterned graphene unit (wave absorbing region) conformally covering the surface of the fiber fabric, and a resin conformally covering the surface of the array patterned graphene unit.

[0032] The present invention also provides a microwave absorbing composite material or microwave absorbing composite material structure containing the above-mentioned patterned montmorillonite fiber fabric microwave absorbing superstructure.

[0033] The microwave absorbing composite material or microwave absorbing composite structure containing the patterned montmorillon fiber fabric microwave absorbing superstructure is prepared by a method including the following steps:

[0034] 1) The patterned montmorillonite fiber fabric microwave absorbing superstructure is directly laminated with one or more of glass fiber reinforced resin prepreg, copper electrode montmorillonite fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg to obtain a microwave absorbing composite preform; or a resin film is laminated again on the patterned montmorillonite fiber fabric microwave absorbing superstructure, and a sufficient amount of resin is impregnated to fully contact the fibers to cover the etched area fibers, and then laminated with one or more of glass fiber reinforced resin prepreg, copper electrode montmorillonite fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg to obtain a microwave absorbing composite preform.

[0035] 2) The obtained microwave absorbing composite material preform is cured to obtain microwave absorbing composite material or microwave absorbing composite material structural component;

[0036] In step 1) of the above method, the patterned montmorillonite fiber fabric microwave absorbing superstructure is alternately laid with one or more of the following: glass fiber reinforced resin prepreg, copper electrode montmorillonite fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg.

[0037] In the microwave absorbing composite preform, the patterned montmorillonite fiber fabric microwave absorbing superstructure has at least one layer;

[0038] At least one or more of the glass fiber reinforced resin prepreg, copper electrode montmorillon fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg are laid in one layer.

[0039] The resin in the patterned montmorillonite fiber fabric microwave absorbing superstructure is the same as the resin in the glass fiber reinforced resin prepreg, the copper electrode montmorillonite fiber fabric reinforced resin prepreg, and the carbon fiber reinforced resin prepreg.

[0040] When copper-containing electrode montmorillonite fiber fabric reinforced resin prepreg is laminated with the patterned montmorillonite fiber fabric microwave absorbing superstructure, the resulting microwave absorbing composite material or microwave absorbing composite structure is a microwave absorption-heating integrated functional material.

[0041] The present invention also provides an arc-shaped composite material for absorbing microwaves containing the above-mentioned patterned montmorillonite fiber fabric microwave absorbing superstructure.

[0042] The arc-shaped composite material absorbing component contains at least two partitioned patterned montmorillon fiber fabric absorbing superstructures.

[0043] The patterned graphene fiber fabric microwave absorbing superstructures contained in the two partitions are both composed of fiber fabric and array patterned graphene units (wave absorbing regions) conformally covering the surface of the fiber fabric, and the array patterned graphene units in the microwave absorbing superstructures set in the two partitions have different shapes and / or sizes.

[0044] The present invention also provides a wave-absorbing superstructure composite material of montmorillonite fiber fabric containing wave-transparent windows.

[0045] The graphene fiber fabric microwave absorbing superstructure composite material containing a wave-transparent window contains the patterned graphene fiber fabric microwave absorbing superstructure, wherein the wave-transparent window is a region that is not covered with graphene; the remaining region is a microwave absorbing region containing an array of patterned graphene units conformally coated on the surface of the fiber fabric.

[0046] Compared with traditional fiber-reinforced composite materials, the montmorillonite fiber fabric microwave-absorbing composite material of this invention achieves microwave absorption while retaining the lightweight and excellent mechanical properties of traditional fiber composite materials. The montmorillonite fiber fabric and its microwave-absorbing superstructure are isomorphic to traditional fibers, thus exhibiting good compatibility with resin-based composite processes and systems. Based on the layup process, it is more conducive to functional integration compared to other microwave-absorbing materials: imparting stealth functionality to glass fiber composites and carbon fiber composites, and creating an integrated microwave absorption-heating montmorillonite fiber composite.

[0047] The designability of the surface graphene functional layer of the shell-core structure of the graphene fiber gives it functional partition designability. By selectively etching, the introduction of wave-transparent windows can be easily achieved without affecting the continuity of the fiber substrate, thereby maintaining the mechanical properties of the fiber-reinforced resin composite.

[0048] Montmorillonite fiber has good flexibility and therefore good adaptability to irregular structures. For irregular structures, partitioned design can help to further improve the wave absorption performance without affecting the mechanical properties of fiber-reinforced composite materials. Attached Figure Description

[0049] Figure 1 This is a process flow diagram of the preparation of styrene fiber fabric microwave absorbing superstructure and styrene fabric microwave absorbing superstructure composite material using the resin mask assisted etching method of the present invention.

[0050] Figure 2 This is a schematic diagram of the resin film impregnating the montmorillonite fibers vertically permeating into the montmorillonite fiber fabric and conformally covering the area covered by the resin film in this invention.

[0051] Figure 3 In this paper, a represents the geometric parameters of the superstructure fractal pattern obtained in Example 1 of the present invention; b represents a physical image of the fractal montmorillonite fabric superstructure prepared in Example 1 of the present invention.

[0052] Figure 4 This describes the microwave absorption performance of the monoxide fiber fabric microwave-absorbing superstructure resin-based composite material sample prepared in Example 1 of the present invention.

[0053] Figure 5 This is a heated infrared image of the integrated microwave absorption and heating montmorillonite fabric superstructure composite material prepared in Example 1 of the present invention.

[0054] Figure 6This is a comparison of the wave absorption performance of carbon fiber and montmorillonite superstructures with carbon fiber and aluminum plate as reflective layers in Example 2 of the present invention.

[0055] Figure 7a shows a photograph of the montmorillonite fiber fabric superstructure with a wave-transmitting window prepared in Example 3 of the present invention, and b shows the electromagnetic properties of the wave-transmitting window and the wave-absorbing region.

[0056] Figure 8 (a) shows the curved surface partitioning design scheme of the curved irregular part prepared in Example 4 of the present invention, and (b) shows the partitioned superstructure and the actual surface structure.

[0057] Figure 9 This is a comparison of the microwave absorption performance of the non-uniform curved surface superstructure microwave absorbing composite material prepared in Example 4 of the present invention with that of the uniform curved surface superstructure microwave absorbing composite material. Detailed Implementation

[0058] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0059] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0060] Example 1: Preparation of Integrated Wave Absorption-Heating Composite Material

[0061] This embodiment follows Figure 1 The flowchart shown illustrates the preparation of an integrated microwave absorption and heating composite material.

[0062] The specific steps are as follows:

[0063] Step 1: Degumming the continuous glass fiber fabric: In an air atmosphere, the temperature is set at 850 ℃ and the treatment time is 3h; Using ethylene as the carbon source, graphene is directly grown on the degummed continuous glass fiber fabric to obtain a continuous montmorillonite glass fiber fabric (sheet resistance of 35 Ω / sq), wherein the graphene is grown using ethylene as the carbon source at a growth temperature of 900 ℃ for 9h.

[0064] Step 2: Use laser processing technology to create patterned paper molds;

[0065] Step 3: Cover the paper template onto the PVC fiberglass fabric and attach the epoxy resin film.

[0066] Step 4: Place the epoxy fiber fabric with the attached resin film into a vacuum bag, evacuate to -930 mbar, and keep it at 70 ℃ for 45 minutes to impregnate it, ensuring that the epoxy resin film fully covers the epoxy glass fiber in the patterned area (see schematic diagram). Figure 2 (as shown)

[0067] Step 5: Remove the paper mold. Only the resin film in the patterned area penetrates into the interior of the montmorillonite fiberglass fabric and wraps it. The resin film in the non-patterned area remains on the paper mold and is removed with the template.

[0068] Step 6: Perform reactive ion etching on the resin-coated montmorillonite glass fiber fabric. The reactive ion etching process uses oxygen as the gas source, employs a medium-frequency power supply at 100% power (300W), and a processing time of 120 minutes to obtain the montmorillonite glass fiber fabric microwave absorbing superstructure preform (see actual image). Figure 3 (b)

[0069] Step 7: Copper electrodes are added to the montmorillonite fiberglass fabric via electroplating, using an acidic CuSO4 solution as the electroplating bath, with the copper plate as the anode and the montmorillonite fiber fabric as the cathode. A voltage (approximately 4 V) is applied, and the current is applied for 5 minutes. A flesh-orange copper electrode is deposited on the montmorillonite fiber, adhering to the surface of the fiber fabric to facilitate uniform current flow. At the break point of the two electroplated copper electrodes, a 6 cm long copper foil electrode is welded for easy connection to the power supply.

[0070] Step 8: Lay-up the composite preform. The lay-up scheme from top to bottom is as follows: 20 layers of glass fiber reinforced epoxy resin prepreg, 1 layer of fractal patterned montmorillonite glass fiber fabric microwave absorbing superstructure preform (prepared in Step 6), 30 layers of glass fiber reinforced epoxy resin prepreg, and 1 layer of montmorillonite glass fiber fabric with added copper electrodes (prepared in Step 7).

[0071] Step 9: Apply release agent to the glass plate, place the composite preform on the glass plate, and vacuum bag it.

[0072] Step 10: Place the vacuum bag in an oven for heating and curing. Once curing is complete, obtain the montmorillonite fiber fabric microwave absorbing superstructure resin-based composite material.

[0073] In step 3, the epoxy resin film is applied so that the resin mass ratio of the patterned area is 39.02%.

[0074] In step 6, the template cuts out the periodic array of square fractal patterns. The structural parameters of the fractal patterns are described as follows: the central square has a side length of 6 mm, and the central square is connected to four squares with a side length of 3 mm through its four vertices; the unit period is 20 mm (e.g., ...). Figure 3 (as shown in a).

[0075] At 16.4 GHz, the absorption peak of the montmorillonite fiber fabric superstructure composite is ( RL min The absorption efficiency reaches -20.1 dB; within the 2-18 GHz range, the effective absorption bandwidth (EAB) reaches 9.76 GHz, with 100% effective absorption coverage in the X-band (8-12 GHz) and 70% effective absorption coverage in the Ku-band (12-18 GHz) (using a 3 mm aluminum plate as the reflector during absorption performance testing). Figure 4 (As shown).

[0076] A voltage of 33V and a current of 4A are applied to the heating layer of the montmorillonite fiber fabric, and the temperature of the montmorillonite fabric composite is ~80℃.

[0077] Figure 5 The image shows the heated infrared image of the integrated microwave absorption and heating styrene fabric superstructure composite.

[0078] Example 2

[0079] This embodiment is the same as Embodiment 1, except that:

[0080] The composite preform is manufactured by layup, with the following layup scheme from top to bottom: 20 layers of glass fiber reinforced epoxy resin prepreg, 1 layer of fractal patterned montmorillonite glass fiber fabric superstructure, 30 layers of glass fiber reinforced epoxy resin prepreg, 1 layer of montmorillonite glass fiber fabric with added copper electrodes, and 1 layer of carbon fiber reinforced prepreg.

[0081] Figure 6 A comparison of the wave absorption performance of carbon fiber and montmorillonite superstructures with carbon fiber and aluminum plates as reflective layers, respectively.

[0082] Compared to Example 1, placing the montmorillonite fiber fabric composite material on top of carbon fiber does not significantly affect its wave absorption performance. The montmorillonite fiber fabric superstructure composite material has good compatibility with the corresponding carbon fiber composite material system and process, and can endow the highly reflective carbon fiber composite material with wave absorption and stealth capabilities.

[0083] Example 3: Preparation of a montmorillonite fiber fabric superstructure composite material containing a wave-transparent window

[0084] This embodiment prepares a graphene glass fiber fabric microwave-absorbing superstructure preform according to steps 1-6 of Embodiment 1. The superstructure preform is divided into a microwave-absorbing region and a microwave-transparent window. The total size of the plate is 300 mm × 300 mm. A 180 mm × 180 mm square region at the center of the plate is designed as a microwave-transparent window, not covered with graphene. The remaining region is the microwave-absorbing region, containing arrayed graphene fiber units (fractal pattern structural parameters are described as follows: the central square has a side length of 6 mm, and the central square is connected to four squares with a side length of 3 mm through its four vertices; the unit period is 20 mm). Figure 7 (as shown in a).

[0085] The composite preform is manufactured by layup, with the following layup scheme from top to bottom: 30 layers of glass fiber reinforced epoxy resin prepreg, 1 layer of montmorillonite glass fiber fabric microwave absorbing superstructure preform, and 20 layers of glass fiber reinforced epoxy resin prepreg.

[0086] Figure 7 In the figure, b represents the electromagnetic properties of the transmission window and the absorption region. The results show that the transmission window is transparent to electromagnetic signals in the range of 8-18 GHz.

[0087] Example 4: Fabrication of a curved composite microwave absorbing component with a montmorillonite fabric superstructure partition design.

[0088] The arc-shaped composite microwave absorbing component includes: a preform of alumina fiber fabric with different periodic superstructures in the equivalent incident angle partition, glass fiber reinforced epoxy resin prepreg before and after the alumina fiber fabric superstructure, and a bottom carbon fiber reflective layer.

[0089] Preforms of γ-alumina fiber fabric with different periodic superstructures were prepared according to steps 1-6 in Example 1: After degumming the γ-alumina fiber cloth, graphene was grown at 900 ℃ for 14 h using ethylene as the carbon source and γ-alumina fiber cloth with a thickness of 0.16 mm as the substrate, resulting in a sheet resistance of 50 Ω / sq for the γ-alumina fiber fabric. Preforms of γ-alumina fiber fabric with different periodic superstructures in different regions were prepared using a resin-assisted mask method.

[0090] Among them, the curved partitions of the montmorillonite alumina fiber fabric preform with different periodic superstructures are as follows: Figure 8 As shown in Figure a, the period of the superstructure unit in region A (equivalent incident angle 0°-20°) is 15 mm, and the period of the superstructure unit in region B (equivalent incident angle 20°-40°) is 13 mm. The figure is a square fractal pattern of periodic array. The structural parameters of the fractal pattern are described as follows: the side length of the central square is 6 mm, and the central square is connected to four squares with a side length of 3 mm through the four vertex corners.

[0091] Using polymethacrylimide (PMI) foam as raw material, a circular arc-shaped mold is manufactured using five-axis machining technology, and a release cloth is attached to obtain a male mold for the circular arc-shaped part.

[0092] The composite preform is manufactured by layering PMI curved foam as a mold and prepregs are laid in sequence. The layering scheme from top to bottom is as follows: 25 layers of glass fiber reinforced epoxy resin prepreg, 1 layer of montmorillonite alumina fiber fabric preform with different periodic superstructures in the partition, 20 layers of glass fiber reinforced epoxy resin prepreg, and 1 layer of carbon fiber reinforced prepreg.

[0093] After the paving is completed, a vacuum bag is applied with a vacuum level >950 mbar. An oven vacuum bag pressing curing process is then used to cure the obtained microwave absorbing composite preform. Once curing is complete, a curved irregular-shaped part of the montmorillonite fabric ultrastructure microwave absorbing composite material is obtained. Figure 8 (b in the image shows the physical diagram of the partitioned superstructure and curved surface structure), and the peak reflectivity and bandwidth were tested from 2 to 18 GHz. Figure 9 The microwave absorption performance of homogeneous and non-homogeneous curved surface superstructure microwave absorbing composite materials (the non-homogeneous curved surface superstructure was prepared in Example 4, and the homogeneous curved surface superstructure was prepared by steps 1-6 of Example 1, wherein the central square has a side length of 6 mm, and the central square is connected to four squares with a side length of 3 mm through the four vertex corners; the unit period is 15 mm, and the layup scheme is the same as that of the montmorillonite fabric superstructure microwave absorbing composite curved irregular part in Example 4) was investigated. The results show that by setting a partitioned superstructure on the curved surface composite microwave absorbing irregular part, a more balanced microwave absorption performance can be obtained without affecting the mechanical properties of the composite part.

[0094] The present invention has been described in detail above. Those skilled in the art will recognize that the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope, and without requiring unnecessary experiments. While specific embodiments have been provided, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including changes made using conventional techniques known in the art that depart from the scope disclosed herein.

Claims

1. A curved surface composite microwave absorbing component containing a patterned montmorillonite fiber fabric microwave absorbing superstructure, characterized in that, The arc-shaped composite material absorbing component contains at least two partitioned patterned montmorillon fiber fabric absorbing superstructures. The patterned graphene fiber fabric microwave absorbing superstructure includes a fiber fabric, at least one array patterned graphene unit conformally coated on the surface of the fiber fabric, and a resin conformally coated on the surface of the array patterned graphene unit. The array patterned graphene units in the absorbing superstructure with at least two partitions have different shapes and / or sizes; The patterned montmorillonite fiber fabric microwave absorbing superstructure is prepared by a method including the following steps: 1) Based on the pattern design and structural parameters of the montmorillonite fiber fabric superstructure, a pattern mold is manufactured, and the resulting pattern mold is then applied to the montmorillonite fiber fabric. 2) Apply the resin film to the montmorillonite fiber fabric covered with the pattern mold, impregnate it, so that the resin penetrates vertically into the montmorillonite fiber fabric and conformally covers the montmorillonite fibers in the area covered by the resin film. 3) Remove the pattern mold and the resin film on it. The resin film in the patterned area remains on the montmorillonite fiber fabric in a patterned manner to obtain a montmorillonite fiber fabric with a patterned resin film attached. Alternatively, skipping steps 1)-3), directly attach the resin film based on the pattern design and structural parameters of the montmorillon fiber fabric superstructure to the montmorillon fiber fabric, impregnate it, and obtain the montmorillon fiber fabric with the patterned resin film attached. 4) Reactive ion etching process: Etching the graphene on the surface of the montmorillonite fiber fabric in the area not covered by the patterned resin film to obtain the patterned montmorillonite fiber fabric microwave absorbing superstructure. The montmorillonite fiber fabric includes montmorillonite glass fiber fabric, montmorillonite quartz fiber fabric, and montmorillonite alumina fiber fabric. The resin film is made of epoxy resin; The impregnation process involves placing the resin-coated montmorillonite fiber fabric into a vacuum bag, evacuating it to -850 to -1000 mbar, and holding it at 50-85°C for 20-60 minutes. In step 4), the oxygen source used in the reactive ion etching process is one or both of air and oxygen, and the processing time is 10 min-120 min.

2. A microwave absorbing composite material or microwave absorbing composite structure containing a patterned montmorillonite fiber fabric microwave absorbing superstructure, wherein the patterned montmorillonite fiber fabric microwave absorbing superstructure is prepared by the method of claim 1, comprising: The fiber fabric, at least one array patterned graphene unit conformally coated on the surface of the fiber fabric, and a resin conformally coated on the surface of the array patterned graphene unit.

3. A method for preparing the microwave absorbing composite material or microwave absorbing composite structure containing the patterned montmorillonite fiber fabric microwave absorbing superstructure as described in claim 2, comprising the following steps: 1) directly laminating the patterned montmorillonite fiber fabric microwave absorbing superstructure with one or more of glass fiber reinforced resin prepreg, copper electrode montmorillonite fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg to obtain a microwave absorbing composite preform, or further laminating a resin film on the patterned montmorillonite fiber fabric microwave absorbing superstructure, impregnating it to allow sufficient resin to fully contact the fibers to cover the etched area fibers, and then laminating it with one or more of glass fiber reinforced resin prepreg, copper electrode montmorillonite fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg to obtain a microwave absorbing composite preform; 2) The obtained microwave absorbing composite preform is cured to obtain microwave absorbing composite material or microwave absorbing composite structural component.

4. The method according to claim 3, characterized in that, In step 1), the patterned montmorillonite fiber fabric microwave absorbing superstructure is alternately laid with one or more of the following: glass fiber reinforced resin prepreg, copper electrode montmorillonite fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg. In the microwave absorbing composite preform, the patterned montmorillonite fiber fabric microwave absorbing superstructure has at least one layer; At least one or more of the glass fiber reinforced resin prepreg, copper electrode montmorillon fiber fabric reinforced resin prepreg, and carbon fiber reinforced resin prepreg are laid in one layer. The resin in the patterned montmorillonite fiber fabric microwave absorbing superstructure is the same as the resin in the glass fiber reinforced resin prepreg, the copper electrode montmorillonite fiber fabric reinforced resin prepreg, and the carbon fiber reinforced resin prepreg.

5. A microwave-absorbing superstructure composite material containing a wave-transparent window made of montmorillonite fiber fabric, characterized in that, The composite material contains a patterned graphene fiber fabric microwave absorbing superstructure, including a microwave absorbing region and a microwave transmission window; the microwave transmission window is a region that is not covered with graphene; the remaining region is a microwave absorbing region containing an array of patterned graphene units conformally coated on the surface of the fiber fabric. The patterned graphene fiber fabric microwave absorbing superstructure is prepared by the method in claim 1, comprising: a fiber fabric, at least one array patterned graphene unit conformally coated on the surface of the fiber fabric, and a resin conformally coated on the surface of the array patterned graphene unit.

Images