A wave-absorbing material based on short-cut wave-absorbing fiber disordered distribution and a preparation method thereof

Abstract

This invention belongs to the field of microwave absorbing composite materials. It provides a microwave absorbing material based on the disordered distribution of short-cut absorbing fibers and its preparation method. This absorbing material introduces a multilayer resonant structure, comprising an absorbing layer and a dielectric layer. The absorbing layer is composed of randomly distributed absorbing fibers, and the dielectric layer is a fabric or a flat plate. The microwave absorption performance of the material is determined by the electromagnetic parameters of each absorbing layer, the dielectric constant of the dielectric layer, and the thickness of the dielectric layer. The electromagnetic performance of the absorbing layer is controlled by the length and content of the absorbing fibers, and the shortest fiber length in the n-layer absorbing layer satisfies L1 < L2 < ... < Ln (n ≥ 3). Due to the electrical loss, resonant loss, and interference effect of the multilayer structure, this absorbing material can achieve ultra-wideband absorption within the GHz frequency band.

Description

Technical Field

[0001] This invention relates to the field of microwave absorbing composite materials, and in particular to a microwave absorbing material based on the disordered distribution of short-cut microwave absorbing fibers and its preparation method. Background Technology

[0002] With the continuous expansion of electromagnetic wave applications, electromagnetic waves of different frequencies permeate people's living spaces. While bringing great convenience to human production and life, the increasingly serious electromagnetic pollution has become an issue that cannot be ignored. The development and application of absorbing materials is one of the key technologies for the development of radar stealth technology. Absorbing materials can convert the energy of incident electromagnetic waves into heat energy for dissipation or cause them to interfere and cancel each other out, reducing echoes. The loss principle of absorbing materials mainly includes interference cancellation, dielectric loss, and resonant loss. To achieve broadband absorption, multiple losses need to act simultaneously, which poses certain challenges to the selection of absorbing agents and the design of absorbing structures.

[0003] The special structure of short-cut absorbing fibers with a large aspect ratio can extend the transmission path of microwaves within the material, increasing its attenuation performance. The good resonance effect between the fiber and the electromagnetic wave wavelength can also effectively increase electromagnetic wave absorption. Reasonable control of the fiber aspect ratio and the construction of fiber absorbing layers provide an effective strategy for preparing broadband composite absorbing materials. The Jaumann absorber structure is similar to the multilayer Salisbury screen absorber, introducing a multilayer resonant structure. Its absorption performance is determined by the electromagnetic properties of each absorbing layer, the electromagnetic parameters of the dielectric layer, and the thickness of the dielectric layer, thus possessing broadband absorption capabilities. For example, patent CN101740143A discloses a method for preparing electromagnetic absorbing materials containing glass-coated magnetic amorphous fibers. This method uses a sieving process to disperse the fibers on a matrix material, and prepares a single-layer absorbing material by controlling the fiber length and annealing. However, according to the embodiments of this patent, only narrowband absorption can be achieved. Chinese invention patent CN11519651A discloses a method for preparing a multi-layer modified carbon fiber-mullite ceramic microwave absorbing material. This patent constructs a multi-layer "sandwich" structure of a modified carbon fiber-mullite ceramic matrix, which exhibits excellent high-temperature resistance and microwave absorption performance. Chinese invention patent CN114619718A discloses a broadband microwave absorbing composite material composed of a reflective layer made of metal composite material, a loss layer made of modified silicon carbide ceramic, and a matching layer with a periodic structure, stacked together. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] Currently, the published absorbing materials exhibit limited absorption efficiency and relatively narrow absorption bandwidth. Furthermore, the absorbing agents used all require modification or complex structural layers, resulting in complex manufacturing processes and hindering rapid and simple control over the absorption performance. Additionally, broadband composite absorbers are generally heavy and thick, limiting their application in practical scenarios. Therefore, there is an urgent need for a broadband composite absorber that is simple to manufacture, allows for rapid and simple control over its absorption performance, is lightweight and thin, and can be widely used in practical applications.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0008] Firstly, this invention provides a microwave absorbing material based on the disordered distribution of short-cut absorbing fibers. The absorbing material comprises n absorbing layers and n dielectric layers; the absorbing layers are composed of absorbing fibers, and the dielectric layers are composed of fabric or polymer; the shortest fiber length contained in the n absorbing layers satisfies the following condition: (n≥3); the absorbing layer and the dielectric layer are distributed at intervals and are sequentially composited into an absorber using an adhesive.

[0009] Furthermore, the absorbing fiber includes metal fiber and non-metal fiber; the metal fiber is one or more of glass-coated amorphous magnetic fiber, stainless steel fiber, polycrystalline iron fiber, iron-nickel fiber and iron-cobalt-nickel fiber; the non-metal fiber is a conductive non-metallic fiber, typically one or more of carbon fiber, modified carbon fiber and modified silicon carbide fiber.

[0010] Furthermore, the absorbing fiber length is 0.5~30mm, and the absorbing fiber content per layer of the absorbing layer is 0.3~8.5g / L. .

[0011] Furthermore, when the absorbing layer contains one type of absorbing fiber length, the absorbing fiber length is a fixed length between 0.5 and 30 mm; the absorbing fibers are randomly distributed. When the absorbing layer contains no fewer than three types of absorbing fiber lengths, the absorbing fiber lengths are corresponding lengths between 0.5 and 30 mm, the length difference between two adjacent absorbing fibers is no greater than 2 mm, and the absorbing fiber lengths are gradient distributed; the absorbing fibers are randomly and equally distributed. When the absorbing fiber lengths of the absorbing layer are centrally normally distributed, the length of the central absorbing fiber is a fixed length between 0.5 and 30 mm, and the other absorbing fiber lengths are no fewer than three lengths, the length difference between two adjacent absorbing fibers is no greater than 2 mm.

[0012] Furthermore, the thickness of the single-layer absorbing layer is 40~3000μm, and the basis weight per square meter of the single-layer absorbing layer is not greater than 50g / m². .

[0013] Furthermore, the dielectric constant of the dielectric layer is 2.1~4.7; the thickness of the dielectric layer is 0.5~12mm, and the thickness of each dielectric layer is matched with the thickness of the corresponding absorbing layer through electromagnetic simulation.

[0014] Furthermore, the weight of the single-layer dielectric layer is no more than 500g / The weight of the absorber is no more than 2000g / .

[0015] Secondly, this invention provides a method for preparing microwave absorbing materials based on the disordered distribution of short-cut absorbing fibers.

[0016] The preparation method includes: S1, preparing the absorbing layer; S2, first forming the absorbing layer and the dielectric layer respectively, and then combining the dielectric layer and the absorbing layer with an adhesive to form the absorbing material based on the disordered distribution of short-cut absorbing fibers, or, first forming a first dielectric layer, and then bonding it with an adhesive to form a first absorbing layer, bonding layer by layer until the nth absorbing layer and the nth dielectric layer are formed, and then bonding to obtain the absorbing material based on the disordered distribution of short-cut absorbing fibers.

[0017] Further, the preparation of the microwave absorbing layer includes: a wet web forming method, a dry web forming method, or a spray resin bonding method; the wet web forming method utilizes a mixture of microwave absorbing fibers and ordinary fibers to form a fiber suspension, which is then transported to a web forming mechanism, reinforced into a fabric, and thermally bonded or needle-punched / hydroentangled to reinforce the nonwoven fabric to obtain the microwave absorbing layer; the dry web forming method utilizes a mixture of microwave absorbing fibers and ordinary fibers, which is mechanically percussed to obtain a uniformly mixed fiber layer; the fiber layer is laid into a web, and thermally bonded or needle-punched / hydroentangled to reinforce the fiber layer to obtain the microwave absorbing layer; the spray resin bonding method involves cutting the microwave absorbing fibers to the appropriate length, mixing them with an adhesive, and then spraying them to obtain the microwave absorbing layer; or cutting the microwave absorbing fiber filaments to the appropriate length using a fiber cutter of a spraying machine, and uniformly mixing them with the adhesive during the spraying process to obtain the microwave absorbing layer.

[0018] Furthermore, the fabric is one or more of viscose fiber, polyester fiber, nylon fiber, cellulose fiber, polypropylene fiber, polyethylene fiber, and cotton fiber; the polymer is one or more of epoxy resin, polytetrafluoroethylene, nylon, and polyurethane; and the adhesive is one or more of polyurethane, polyacrylic resin, polysulfide rubber, silicone rubber, chloroprene rubber, butyl rubber, epoxy resin, unsaturated polyester resin, phenolic resin, and polyvinyl chloride resin.

[0019] (III) Beneficial Effects

[0020] The beneficial effect of this invention is that, compared with the prior art, it provides a microwave absorbing material based on the disordered distribution of short-cut absorbing fibers and its preparation method.

[0021] 1. The microwave absorbing material based on the disordered distribution of short-cut absorbing fibers provided by this invention has a multi-layer resonant structure. Its electromagnetic properties can be effectively controlled by adjusting the parameters of the absorbing layer and the dielectric layer, achieving ultra-wideband absorption. The fiber length distribution and content of each absorbing layer, the thickness of the dielectric layer, and the multi-layer structure distribution are specified.

[0022] 2. The microwave absorbing material based on the disordered distribution of short-cut absorbing fibers provided by the present invention introduces fiber absorbing agent and combines it with Jaumann absorbing structure, so that the microwave absorber has electrical loss, resonance loss and interference effect, and can achieve "light, thin, wide and strong".

[0023] 3. The present invention provides a method for preparing microwave absorbing materials based on disordered distribution of short-cut fibers, including methods for preparing single-layer and multi-layer microwave absorbing materials, which have both microwave absorption and flexibility, and are relatively thin, and can be applied to equipment of various forms. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the bow-shaped test of a microwave absorbing material based on the disordered distribution of short-cut absorbing fibers is shown in an embodiment of the present invention.

[0026] Figure 2 The diagram illustrates a Jaumann-like absorber structure based on a randomly distributed short-cut absorbing fiber according to an embodiment of the present invention; a) is a planar schematic diagram; b) is a three-dimensional schematic diagram.

[0027] Figure 3 The diagram shows the reflectance curve of a double-layer absorbing fabric based on a randomly distributed short-cut absorbing fiber according to an embodiment of the present invention.

[0028] Figure 4 The diagram shows the reflectivity curve of a multilayer composite absorbing laminate based on a disordered distribution of short-cut absorbing fibers, according to an embodiment of the present invention.

[0029] Figure 5 The diagram shows the reflectance curve of a multilayer composite microwave absorbing fabric based on a disordered distribution of short-cut microwave absorbing fibers, according to an embodiment of the present invention.

[0030] Figure 6 The diagram shows the reflectance curve of another double-layer absorbing fabric based on the disordered distribution of short-cut absorbing fibers, according to an embodiment of the present invention. Detailed Implementation

[0031] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0033] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0034] According to GJB2038-2011 "Test Method for Reflectivity of Radar Absorbing Materials", the reflectivity of multilayer absorbers was tested using the bow-shaped method, with a test frequency band of 2-18 GHz. The test equipment and environment are as follows: Figure 1 As shown, the transmitting antenna, receiving antenna, and sample stage center are on the same plane and point towards the center of the circle. The sample size is 18cm × 18cm. Before testing, the vector network analyzer is preheated for 20 minutes. First, the receiving power of a metal aluminum plate of the same size as the sample is tested, and then the receiving power of the sample placed on the aluminum plate is tested. The sample reflectivity is calculated according to the formula.

[0035] Based on the disordered distribution of absorbing fibers, the schematic diagram of the layered structure of the dielectric combination is as follows: Figure 2 As shown.

[0036] Different types of fiber matrix materials and dielectric layers can meet the needs of different applications. The dielectric materials with dielectric constants within the scope of the claims are common materials with dielectric constant values ​​that can all be used in composite absorbing materials. The thickness of the dielectric layer is determined by the electromagnetic resonant microwave absorption characteristics and the quarter-wavelength matching absorption characteristics of the absorbing fiber. Therefore, the matching thickness of the dielectric layer corresponding to different absorbing fiber layers is not the same, and the dielectric layer thickness can be calculated by simulation software.

[0037] Example 1:

[0038] This embodiment analyzes the reflectivity of a double-layered absorbing fabric obtained by combining glass-coated amorphous magnetic fiber chopped strands of different lengths as absorbing fibers with cellulose fiber and polyester fiber using a wet web forming process to prepare an absorbing layer. Cellulose fiber and polyester fiber are used to prepare a dielectric layer using a wet web forming process.

[0039] Glass-coated amorphous magnetic fibers (core diameter 18µm, shell thickness 2µm) with a fineness of 26 dtex were chopped into lengths of 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, and 12mm. The chopped fibers of 4mm, 5mm, 6mm, and 7mm were then processed at a weight of 1g / ... 0.5g / 0.5g / and 1g / A nonwoven fabric was prepared by blending cellulose fibers and polyester fibers, with a total basis weight of 100 g / L. As the first absorbing layer; cellulose fibers and polyester fibers are mixed to prepare a nonwoven fabric with a total basis weight of 50g / m². As the first medium layer; short shreds of 8mm, 9mm, 10mm, 11mm and 12mm were all chopped at a weight of 0.8g / g. A nonwoven fabric was prepared by blending cellulose fibers and polyester fibers, with a total basis weight of 160 g / L. As the second absorbing layer; cellulose fibers and polyester fibers are mixed to prepare a nonwoven fabric with a total basis weight of 70g / m². The fabric is then bonded with a waterborne polyurethane with a solid content of 30% to form a double-layer microwave absorbing fabric.

[0040] The reflectivity of the obtained double-layer absorbing fabric was tested using the arch method. The test results are as follows: Figure 3 As shown, within the 2-18GHz test range, the reflectivity exhibits two peaks, at -7.4dB and -14.1dB respectively; the bandwidth not exceeding -5dB is approximately 13.6GHz, and the bandwidth not exceeding -10dB is approximately 5GHz. This demonstrates that the double-layer composite absorbing fabric, with a total thickness not exceeding 3.5mm, possesses a wide absorbing bandwidth while also exhibiting flexibility.

[0041] Example 2:

[0042] This embodiment analyzes the reflectivity of multilayer composite absorbing panels prepared by bonding carbon fiber short filaments of different lengths as absorbing layers onto epoxy resin flat dielectric layers of different thicknesses. The absorbing layers are prepared by a spray resin bonding method, and the dielectric is a polymer.

[0043] Carbon fibers with a diameter of 8μm were chopped into lengths of 3.5mm, 6mm, 10mm, and 13.5mm. The chopped carbon fibers of 3.5mm, 6mm, 10mm, and 13.5mm were then shredded at a weight of 2g / g. 2g / 2.5g / and 3g / The fibers are evenly and randomly distributed on epoxy resin plates with thicknesses of 1mm, 1mm, 1.5mm and 2mm. Water-based polyurethane is sprayed onto each of the four plates to bond the fibers and epoxy resin plates together. Then, these four plates are stacked in sequence to obtain a multi-layer composite wave-absorbing board.

[0044] The reflectivity of the obtained multi-layer composite absorbing panel was tested, with the fourth layer close to the metal backing during the test. The reflectivity test results are as follows: Figure 4 As shown, within the 2-18GHz test range, the reflectivity exhibits two peaks, at -13.1dB and -14dB respectively; the bandwidth not exceeding -5dB is approximately 13GHz, and the bandwidth not exceeding -10dB is approximately 8.16GHz. The resulting multilayer composite absorbing laminate possesses excellent absorbing performance characterized by strong absorption, wide bandwidth, and lightweight properties.

[0045] Example 3:

[0046] This embodiment analyzes the reflectivity of multilayer composite microwave absorbing fabrics prepared by bonding stainless steel chopped filaments of different lengths as microwave absorbing layers onto open-cell polyurethane foam dielectric layers of different thicknesses. The microwave absorbing layers are prepared by a spray resin bonding method, and the dielectric is fabric.

[0047] Stainless steel fibers with a diameter of 35μm were chopped into short pieces of 0.8mm, 1mm, 1.5mm, 2.6mm, 4.5mm, 5mm, 5.5mm, 10.5mm, 11mm, and 15.5mm. The 0.8mm, 1mm, 1.5mm, and 2.6mm stainless steel fibers were then chopped into filaments, with each filament weighing 4g / g. 4.5g / 5g / and 5.5g / The fibers were evenly and randomly sprinkled onto a 0.8mm thick open-cell polyurethane foam as the first wave-absorbing layer; short-cut stainless steel fibers of 4.5mm, 5mm, and 5.5mm were then chopped at a weight of 2.5g / g. 5g / and 4g / The fibers were evenly and randomly sprinkled onto a 1.5mm thick porous polyurethane sponge as a second wave-absorbing layer; short chopped stainless steel fibers of 10.5mm, 11mm, and 15.5mm were then shredded at 3g / g weights respectively. 4g / and 3g / The material is evenly and randomly sprinkled onto a 1.1mm thick open-cell polyurethane foam as the third absorbing layer. Then, the three absorbing layers are stacked sequentially and bonded together using oil-based polyurethane to obtain a multi-layer composite absorbing fabric.

[0048] The reflectivity of the obtained multi-layer composite microwave absorbing fabric was tested, and the test results are as follows: Figure 5 Within the 2-18GHz test range, the bandwidth of no more than -5dB is approximately 15.36GHz, and the bandwidth of no more than -10dB is approximately 7.84GHz. The resulting multi-layer stainless steel fiber absorbing fabric, with a thickness of 3.4mm, can cover almost the entire 2-18GHz frequency band with a bandwidth of less than -5dB, and has the advantages of wide absorption bandwidth, thin thickness, and light weight.

[0049] Example 4:

[0050] This embodiment analyzes the reflectivity of a double-layered absorbing fabric obtained by combining glass-coated amorphous magnetic fiber chopped strands of different lengths with polyester fiber as absorbing fibers and polyester fiber using a dry web forming process to prepare an absorbing layer.

[0051] Glass-coated amorphous magnetic fibers (core diameter 18µm, shell thickness 2µm) with a fineness of 26 dtex were chopped into lengths of 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, and 12mm. The chopped fibers of 4mm, 5mm, 6mm, and 7mm were then processed at a weight of 0.5g / g. 1g / 1g / and 0.5g / Blended with polyester fibers, the fabric is carded into a web and then needle-punched for reinforcement to obtain a nonwoven fabric with a total weight of 100g / m². As the first absorbing layer, polyester fibers are carded into a web and needle-punched for reinforcement to obtain a nonwoven fabric with a total weight of 50g / m². As the first medium layer; short shredded wires of 8mm, 9mm, 10mm, 11mm and 12mm were respectively weighed at 0.25g / g. 1g / 1.5g / 1g / and 0.25g / Blended with polyester fibers, and subjected to the same carding and needle-punching reinforcement processes, a nonwoven fabric is obtained with a total weight of 160g / m². As the second wave-absorbing layer, polyester fibers are carded into a web and needle-punched for reinforcement to obtain a nonwoven fabric with a total weight of 70g / m². The fabric is then bonded with a waterborne polyurethane with a solid content of 30% to form a double-layer microwave absorbing fabric.

[0052] The reflectivity of the obtained double-layer absorbing fabric was tested using the arch method. The test results are as follows: Figure 6As shown, within the 2-18GHz test range, the reflectivity exhibits a double peak, at -9.5dB and -13.5dB respectively; the bandwidth not exceeding -5dB is approximately 14GHz, and the bandwidth not exceeding -10dB is approximately 4.5GHz. It is evident that, with the same fiber length and dielectric layer, the double-layer composite absorbing fabric prepared from normally distributed absorbing fibers possesses a wider absorbing bandwidth, thus contributing to a certain degree of improvement in overall absorbing performance.

[0053] As can be seen from the above embodiments, the microwave absorbing material prepared by this invention uses chopped absorbing fibers as the absorbing agent and polymers such as resin and polyurethane or fabrics such as polyester and polypropylene as the dielectric layer. By controlling the fiber length, density and distribution, dielectric layer thickness, and the structural design of each layer, broadband absorption is achieved in the 2-18 GHz frequency band. Moreover, the preparation process of the microwave absorbing material is simple, and the microwave absorption performance of the absorber can be quickly and easily controlled.

Claims

1. A wave-absorbing material based on the disordered distribution of short-cut wave-absorbing fibers, characterized in that, The wave-absorbing material comprises n layers of wave-absorbing layers and n layers of medium layers, n is the number of layers of the wave-absorbing layers, n>=3; the wave-absorbing layers are composed of wave-absorbing fibers, and the medium layers are composed of fabrics or polymers; the shortest fiber length contained in each layer of the wave-absorbing layers satisfies: ; The wave-absorbing layers and the dielectric layers are spaced apart from each other and are compounded into a wave-absorbing body in sequence by an adhesive; The wave-absorbing fibers comprise metal fibers and non-metal fibers; The metal fibers are one or more of glass-coated amorphous magnetic fibers, stainless steel fibers, polycrystalline iron fibers, iron-nickel fibers and iron-cobalt-nickel fibers; The non-metal fibers are electrically conductive non-metal fibers, comprising one or more of carbon fibers, modified carbon fibers and modified silicon carbide fibers; The single-layer thickness of the wave-absorbing layer is 40-3000 μm, and the single-layer square meter gram weight of the wave-absorbing layer is not greater than 50 g / m2 ; The dielectric layer has a dielectric constant of 2.1-4.7 and a thickness of 0.5-12 mm, and the thickness of each dielectric layer is matched with the thickness of the corresponding wave-absorbing layer through electromagnetic simulation; The preparation method of the wave-absorbing material based on the random distribution of the chopped wave-absorbing fibers comprises the following steps: S1, preparing the wave-absorbing layer; S2, forming the wave-absorbing layer and the dielectric layer respectively, and then compounding the dielectric layer and the wave-absorbing layer by an adhesive to form the wave-absorbing material based on the random distribution of the chopped wave-absorbing fibers.

2. The wave-absorbing material based on the disorder distribution of the short-cut wave-absorbing fiber according to claim 1, characterized in that, The wave-absorbing fiber has a length of 0.5-30 mm, and the wave-absorbing layer has a wave-absorbing fiber content of 0.3-8.5 g per layer .

3. The wave-absorbing material based on the disorder distribution of the chopped wave-absorbing fiber according to claim 2, characterized in that, When the wave-absorbing layer contains one wave-absorbing fiber length, the wave-absorbing fiber length is one fixed length in the range of 0.5-30 mm, and the wave-absorbing fibers are randomly distributed; When the wave-absorbing layer contains no less than three wave-absorbing fiber lengths, the wave-absorbing fiber lengths are corresponding lengths in the range of 0.5-30 mm, the difference between adjacent two wave-absorbing fiber lengths is no more than 2 mm, and the wave-absorbing fibers are randomly and equally distributed; When the wave-absorbing fiber lengths of the wave-absorbing layer are normally distributed, the central wave-absorbing fiber length is one fixed length in the range of 0.5-30 mm, and the other wave-absorbing fiber lengths are no less than three lengths, and the difference between adjacent two wave-absorbing fiber lengths is no more than 2 mm.

4. The wave-absorbing material based on the disorder distribution of the chopped wave-absorbing fiber according to claim 1, characterized in that, The weight of the single-layer dielectric layer is not more than 500 g / m 2 ; the weight of the wave absorber is not more than 2000 g / m .

5. A method for preparing a wave-absorbing material based on the disordered distribution of short-cut wave-absorbing fibers, characterized in that, The preparation method of the wave-absorbing material based on the random distribution of the chopped wave-absorbing fibers comprises the following steps: S1, preparing the wave-absorbing layer; S2, forming the wave-absorbing layer and the dielectric layer respectively, and then compounding the dielectric layer and the wave-absorbing layer by an adhesive to form the wave-absorbing material based on the random distribution of the chopped wave-absorbing fibers.

6. The method according to claim 5, wherein the method is characterized by, The preparation of the wave-absorbing layer comprises a wet-laid method, a dry-laid method or a resin spraying and bonding method; The wet-laid method uses wave-absorbing fibers and ordinary fibers to mix into a fiber suspension pulp, which is conveyed to a web-forming mechanism, reinforced into a cloth, and then hot-bonded or needle-punched and water-jet reinforced to obtain the wave-absorbing layer; The dry-laid method uses wave-absorbing fibers and ordinary fibers to mix and mechanically impact to obtain a uniformly mixed fiber layer, which is laid into a web, and then hot-bonded or needle-punched and water-jet reinforced to obtain the wave-absorbing layer; The resin spraying and bonding method cuts the wave-absorbing fibers into corresponding lengths, mixes the wave-absorbing fibers with an adhesive, and then sprays to obtain the wave-absorbing layer; or the resin spraying and bonding method cuts the wave-absorbing fiber filaments into corresponding lengths by a fiber cutter of a spraying machine, uniformly mixes the wave-absorbing fibers with an adhesive in the spraying process, and then sprays to obtain the wave-absorbing layer.

7. The wave-absorbing material based on short-cut wave-absorbing fiber disorder distribution according to claim 1, characterized in that, The fabric is one or several of viscose fiber, polyester fiber, nylon fiber, cellulose fiber, polypropylene fiber, polyethylene fiber and cotton fiber; the high polymer is one or several of epoxy resin, polytetrafluoroethylene, nylon and polyurethane; the adhesive is one or several of polyurethane, polyacrylic resin, polysulfide rubber, silicone rubber, chloroprene rubber, butyl rubber, epoxy resin, unsaturated polyester resin, phenolic resin and polyvinyl chloride resin.

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