Infrared and radar compatible stealth material containing silicone rubber and preparation method thereof

Abstract

The present invention belongs to the field of stealth materials and specifically discloses a stealth material containing silicone rubber that is compatible with both infrared and radar, and a method for preparing the same. The stealth material comprises, from bottom to top, a stacked radar absorbing layer, a wave-transparent fabric layer, and an infrared stealth layer. The radar absorbing layer comprises multiple stacked absorbing layers, at least two of which provide radar stealth for different wavelengths, and each of the absorbing layers comprises a silicone rubber matrix. The stealth material provided by the present invention combines infrared and radar stealth, particularly possessing a wide absorbing frequency band. It can be manufactured to absorb electromagnetic waves in different frequency bands, such as L, S, C, X, Ku, and Ka, depending on actual conditions. The wave-transparent fabric layer enhances the material's mechanical properties, while the structural layers exhibit strong bonding, preventing the risk of detachment during use. Furthermore, the stealth material is simple to prepare and amenable to large-scale mass production.

Description

Technical Field

[0001] The present invention belongs to the technical field of stealth materials, and in particular relates to an infrared and radar compatible stealth material containing silicone rubber and a preparation method thereof. Background Art

[0002] In recent years, with the rapid development of multi-spectral detection technology, single-function stealth materials can no longer meet the needs of their applications. The need for multi-band compatible stealth materials, especially infrared and radar compatible stealth materials, has become a research and development focus. This is because infrared radar stealth materials can reduce the reflection and scattering of electromagnetic waves through their own absorption and attenuation, achieving electromagnetic wave loss, thereby significantly reducing the target's radar cross-section. At the same time, infrared stealth materials effectively solve the problem of target infrared image segmentation, enhance the degree of integration with the environment, and reduce the probability of target detection.

[0003] However, radar stealth is based on the absorption principle—that is, it achieves radar stealth by absorbing radar waves to reduce the target's surface reflection of radar waves. Therefore, radar stealth requires materials with high absorption and low reflection. Infrared stealth, on the other hand, primarily achieves infrared stealth by increasing the reflectivity of an object's surface and utilizing the principle of reflecting infrared rays. Therefore, infrared stealth requires materials with low absorption and high reflection. Clearly, the conflicting principles between radar stealth and infrared stealth create significant difficulties in developing stealth materials compatible with both infrared and radar.

[0004] Currently, infrared and radar-compatible stealth materials are categorized into two types: single and composite. Single infrared and radar-compatible stealth materials remain limited to theoretical research due to various practical manufacturing issues, including: 1) they are single-layer materials, making their dielectric properties difficult to control and resulting in a narrow radar absorption band; and 2) their generally high infrared emissivity, making it difficult to meet infrared stealth requirements. Composite infrared and radar-compatible stealth materials, on the other hand, primarily involve applying an infrared stealth functional layer to the surface of a radar stealth material. The key to achieving this is that the infrared stealth functional layer possesses both high radar transmittance and high infrared reflectivity. Commonly used infrared stealth functional layers include low-emissivity coatings and metal films, but both negatively impact the radar absorbing properties of the underlying radar-absorbing material, making it difficult to achieve effective infrared and radar stealth compatibility. In addition, existing composite stealth materials are generally multi-layer structures. Although they can achieve stealth effects that are compatible with infrared and radar to a certain extent, they have the disadvantages of a narrow absorption frequency band and difficulty in controlling the stability of absorption performance. At the same time, the mechanical properties are weak, and the weak bonding force between the layers of the structure can easily lead to the risk of falling off and causing exposure. Therefore, it is difficult to meet the needs of actual use.

[0005] In view of this, this invention is proposed. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide an infrared and radar compatible silicone rubber stealth material and a preparation method thereof, which are mainly used to solve the problem that existing stealth materials are difficult to be compatible with infrared and radar stealth effects.

[0007] The purpose of the present invention is to solve the problem through the following technical solutions:

[0008] On the one hand, the present invention provides an infrared and radar compatible stealth material containing silicone rubber, wherein the stealth material is composed of a radar absorbing layer, a wave-transparent fabric layer and an infrared stealth layer stacked in sequence from bottom to top;

[0009] The radar absorbing layer comprises a plurality of stacked absorbing layers, and at least two of the absorbing layers perform radar stealth for different bands. At the same time, any one of the radar absorbing layers comprises a silicone rubber matrix.

[0010] Furthermore, any one of the radar absorbing layers is made of the following components in parts by weight:

[0011] 80 to 120 parts of silicone rubber matrix;

[0012] 300 to 800 parts of absorbent;

[0013] 0.5 to 2 parts of vulcanizing agent.

[0014] Furthermore, the absorbent includes but is not limited to at least one of ferrite, carbonyl iron, iron silicon chromium, conductive carbon black, graphite, conductive polyaniline, conductive polypyrrole, and silicon carbide, and the particle size of the absorbent is 3 μm to 70 μm.

[0015] Furthermore, the wave-transmitting fabric layer is made of glass fiber cloth with a mesh structure, and the thickness of the wave-transmitting fabric layer is 0.03 mm to 1 mm.

[0016] Furthermore, the infrared stealth layer is made of the following components by weight: 90 to 110 parts of adhesive, 15 to 25 parts of aluminum powder, 0.5 to 1.5 parts of dispersant, 0.5 to 1 part of leveling agent, 0.3 to 0.6 part of defoaming agent, 50 to 80 parts of diluent and 1 to 2 parts of coupling agent.

[0017] Furthermore, the adhesive is liquid silicone rubber;

[0018] The diluent includes at least one of iron n-octane, n-pentane, xylene, and tetrahydrofuran.

[0019] Furthermore, the particle size of the aluminum powder is 10 μm to 15 μm.

[0020] Furthermore, the coupling agent includes but is not limited to one of KH550, KH560, and KH570.

[0021] On the other hand, the present invention provides a method for preparing the infrared and radar compatible stealth material containing silicone rubber as described above, which specifically comprises the following steps:

[0022] Step 1: Prepare radar absorbing layer

[0023] In parts by weight, 80 to 120 parts of a silicone rubber matrix, 300 to 800 parts of an absorbent, and 0.5 to 2 parts of a vulcanizing agent are mixed and kneaded in different proportions to obtain a plurality of different mixed preformed rubbers; the plurality of different mixed preformed rubbers are then allowed to stand for a set time to obtain a plurality of different mixed rubbers; the plurality of different mixed rubbers are then cut to obtain a plurality of different mixed rubber sheets, and the plurality of different mixed rubber sheets are stacked in a mold for compression molding and vulcanization to obtain a radar absorbing layer comprising multiple absorbing layers, which is used to provide radar stealth for different bands;

[0024] Step 2: Prepare the wave-transparent fabric layer

[0025] First, the wave-transparent fabric is cut to obtain a wave-transparent fabric sheet; then the wave-transparent fabric sheet is laid flat on the surface of the radar absorbing layer obtained in step 2, thereby obtaining a wave-transparent fabric layer;

[0026] Step 3: Prepare infrared stealth layer

[0027] In parts by weight, 90 to 110 parts of an adhesive, 15 to 25 parts of aluminum powder, 0.5 to 1.5 parts of a dispersant, 0.5 to 1 part of a leveling agent, 0.3 to 0.6 parts of a defoaming agent, 50 to 80 parts of a diluent, and 1 to 2 parts of a coupling agent are sequentially added into a container, and ultrasonic dispersion is performed until uniform dispersion is achieved to obtain an infrared stealth coating. Finally, the infrared stealth coating is applied to the wave-transparent fabric layer obtained in step 2 by a roller coating method, and after drying, an infrared stealth layer is obtained.

[0028] Furthermore, in step 1, the compression vulcanization molding process parameters are as follows: vulcanization temperature is 170° C. to 180° C., vulcanization pressure is 10 MPa to 15 MPa, and vulcanization time is 5 min to 15 min;

[0029] In step 3, the drying process parameters are as follows: temperature is 140° C. to 160° C., and drying time is 0.5 h to 2 h.

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

[0031] The stealth material provided by the present invention has a multi-layer structure, which is composed of a radar absorbing layer, a wave-transmitting fabric layer, and an infrared stealth layer stacked from bottom to top. Compared with existing composite materials, this stealth material has at least the following advantages:

[0032] First, the radar absorbing layer of the present invention comprises a plurality of stacked absorbing layers, and any one of the absorbing layers comprises a silicone rubber matrix. Due to the (Si-O-Si) bonds and inorganic properties in the silicone rubber structure, it has excellent properties in terms of heat resistance, chemical stability, wear resistance, and corrosion resistance. By regulating the composition and content of the absorbent in each absorbing layer, the absorbing frequency band of each absorbing layer can be regulated, thereby enabling the radar absorbing layer to have a wider absorbing frequency band and achieve the purpose of broadband absorption. At the same time, the multi-layer absorbing layer is formed by compression vulcanization, so that the finally formed radar absorbing layer has an integrated hierarchical structure, which prevents any layer of the multi-layer absorbing layer from falling off and ensures a long-term absorbing effect.

[0033] Secondly, since the radar absorbing layer is mainly made of a silicone rubber matrix, but the mechanical strength of the rubber matrix is ​​limited, the present invention provides a wave-transparent fabric layer between the radar absorbing layer and the infrared stealth layer. Since the wave-transparent fabric layer has certain mechanical and load-bearing capabilities, after bonding the wave-transparent fabric layer to the rubber matrix, the two become an integrated structural composite material, thereby improving the mechanical properties of infrared and radar compatible stealth;

[0034] Third, the infrared stealth layer of the present invention uses liquid silicone rubber of the same system (silicone rubber system) as an adhesive, and the wave-transparent fabric layer uses a glass fiber cloth with a mesh structure. The infrared stealth layer is in a liquid state before curing. When roller-coated, the liquid will penetrate along the mesh holes. The liquid silicone has strong adhesion, so that the prepared infrared stealth layer and the radar absorbing layer have good bonding strength and there is no falling-off problem.

[0035] In summary, the stealth material provided by the present invention has both infrared and radar stealth effects, especially it has a wide wave absorption band, and can be made to absorb electromagnetic waves in different frequency bands such as L, S, C, X, Ku, Ka, etc. according to actual conditions. The mechanical properties of the material are increased by setting the wave-transparent fabric layer. At the same time, the bonding force between the structural layers is strong, avoiding the risk of falling off during use. In addition, the preparation of the stealth material does not involve too many complicated processes, so it is simple to operate and easy to mass-produce. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the invention.

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] Figure 1 This is a schematic structural diagram of the infrared and radar compatible stealth material containing silicone rubber provided in Example 1 of the present invention;

[0039] Figure 2 This is a flow chart of the method for preparing stealth materials provided by the present invention.

[0040] Among them: 1 is the radar absorbing layer; 2 is the wave-transparent fabric layer; 3 is the infrared stealth layer. DETAILED DESCRIPTION

[0041] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Instead, they are merely examples consistent with certain aspects of the present invention as detailed in the appended claims.

[0042] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention is described in further detail below with reference to the accompanying drawings and embodiments.

[0043] Example 1

[0044] See also Figure 1 An embodiment of the present invention provides an infrared and radar-compatible stealth material containing silicone rubber. The stealth material has a multi-layer structure, consisting of, from bottom to top, a radar absorbing layer 1, a wave-transparent fabric layer 2, and an infrared stealth layer 3. The radar absorbing layer 1 comprises multiple absorbing layers stacked together, at least two of which provide radar stealth for different bands. Furthermore, each absorbing layer in the radar absorbing layer 1 comprises a silicone rubber matrix.

[0045] Specifically, in the embodiment of the present invention, the radar absorbing layer 1 includes two absorbing layers, and the two absorbing layers are respectively used for radar stealth for the X-band and the C-band. Any one of the absorbing layers is composed of 80 to 120 parts of a silicone rubber matrix, 300 to 800 parts of an absorbent, and 0.5 to 2 parts of a vulcanizing agent, by weight.

[0046] More specifically, the X-band stealth radar absorbing layer in this embodiment comprises the following components, by weight: 100 parts methyl vinyl silicone rubber, 700 parts iron silicon chromium, and 1 part 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the iron silicon chromium has a particle size of 25 μm. The C-band stealth radar absorbing layer comprises the following components, by weight: 100 parts methyl vinyl silicone rubber, 500 parts carbonyl iron, and 1 part 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the carbonyl iron has a particle size of 3 μm.

[0047] In the embodiment of the present invention, the wave-transmitting fabric layer 2 is made of glass fiber cloth with a mesh structure and a thickness of 0.03 mm.

[0048] The infrared stealth layer of the present invention comprises the following components in parts by weight: 90 to 110 parts of an adhesive, 15 to 25 parts of aluminum powder, 0.5 to 1.5 parts of a dispersant, 0.5 to 1 part of a leveling agent, 0.3 to 0.6 parts of a defoaming agent, 50 to 80 parts of a diluent, and 1 to 2 parts of a coupling agent.

[0049] Specifically, the infrared stealth layer 3 in this embodiment includes the following components by weight: 100 parts of liquid silicone rubber, 20 parts of aluminum powder, 1 part of dispersant, 0.8 parts of leveling agent, 0.5 parts of defoaming agent, 65 parts of n-octane, and 1.5 parts of KH570. Preferably, the particle size of the aluminum powder is 13 μm.

[0050] like Figure 2 As shown, the infrared and radar compatible silicone rubber stealth material provided in the embodiment of the present invention is prepared by the following method:

[0051] 1) Preparation of radar absorbing layer 1

[0052] A. Mixing 100 parts by weight of methyl vinyl silicone rubber, 700 parts of iron silicon chromium, and 1 part of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a pre-mixed rubber; and allowing the pre-mixed rubber to stand for 24 hours to obtain a pre-mixed rubber having X-band stealth properties.

[0053] B. Mixing 100 parts by weight of methyl vinyl silicone rubber, 500 parts of carbonyl iron, and 1 part of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 24 hours to obtain a C-band stealth rubber mixture.

[0054] C. Cutting the obtained mixed rubber for X-band stealth and the mixed rubber for C-band stealth to obtain mixed films for X-band stealth and mixed films for C-band stealth; stacking the mixed films for X-band stealth and the mixed films for C-band stealth in a mold in sequence, performing compression molding and vulcanization molding, to obtain a radar absorbing layer 1;

[0055] The compression vulcanization molding process parameters are as follows: vulcanization temperature is 175°C, vulcanization pressure is 13 MPa, and vulcanization time is 10 min;

[0056] 2) Preparation of wave-transmitting fabric layer 2

[0057] First, the wave-transmitting fabric is cut to obtain a wave-transmitting fabric sheet; then, the wave-transmitting fabric sheet is laid flat on the surface of the radar absorbing layer obtained in step 2, thereby obtaining the wave-transmitting fabric layer 2;

[0058] 3) Preparation of infrared stealth layer 3

[0059] A. In parts by weight, 100 parts of liquid silicone rubber, 20 parts of aluminum powder, 1 part of dispersant, 0.8 parts of leveling agent, 0.5 parts of defoaming agent, 65 parts of n-octane and 1.5 parts of KH570 were added to a paint mixing cup in sequence, and ultrasonic dispersion was performed until uniform dispersion was achieved to obtain an infrared stealth coating;

[0060] B. The infrared stealth coating is applied to the wave-transmitting fabric layer obtained in step 2) by roller coating, and then dried at 150° C. for 1 hour to obtain the infrared stealth layer 3.

[0061] In order to further verify the effectiveness of the present invention, the inventors conducted relevant tests on the reflectivity and mechanical properties of the stealth material samples obtained in this embodiment. The test results are as follows: the infrared and radar-compatible silicone rubber stealth material prepared in the embodiment of the present invention has a reflectivity of ≤-10dB in the frequency range of 2GHz to 18GHz, an infrared emissivity of 0.296, a tensile strength of 12MPa, an elongation at break of 55%, and a tear strength of 55kN / m.

[0062] Example 2

[0063] An embodiment of the present invention provides an infrared and radar compatible silicone rubber stealth material, which also has a three-layer structure as a whole, including a radar absorbing layer 1, a wave-transparent fabric layer 2 and an infrared stealth layer 3 stacked in sequence from bottom to top.

[0064] Different from Example 1, the radar absorbing layer 1 of this embodiment includes three absorbing layers, which respectively perform radar stealth for the S band, X band and C band. Any one of the absorbing layers is composed of 80 to 120 parts of silicone rubber matrix, 300 to 800 parts of absorbent and 0.5 to 2 parts of vulcanizing agent in parts by weight.

[0065] Specifically, the radar absorbing layer for S-band stealth in this embodiment comprises the following components, by weight: 80 parts methyl vinyl silicone rubber, 300 parts conductive polyaniline, and 0.5 parts 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the conductive polyaniline has a particle size of 30 μm. The radar absorbing layer for X-band stealth comprises the following components, by weight: 120 parts methyl vinyl silicone rubber, 800 parts conductive polypyrrole, and 2 parts 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the conductive polypyrrole has a particle size of 70 μm. The radar absorbing layer for C-band stealth includes the following components by weight: 110 parts of methyl vinyl silicone rubber, 600 parts of ferrite, and 1.5 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the particle size of the ferrite is 60 μm.

[0066] In the embodiment of the present invention, the thickness of the wave-transmitting fabric layer 2 is 0.5 mm.

[0067] In the embodiment of the present invention, the infrared stealth layer 3 comprises the following components, measured by weight: 90 parts liquid silicone rubber, 15 parts aluminum powder, 0.5 parts dispersant, 0.5 parts leveling agent, 0.3 parts defoaming agent, 50 parts xylene, and 1 part KH560. Preferably, the aluminum powder has a particle size of 10 μm.

[0068] like Figure 1 As shown, the infrared and radar compatible silicone rubber stealth material provided in the embodiment of the present invention is prepared by the following method:

[0069] 1) Preparation of radar absorbing layer 1

[0070] A. Mixing 80 parts by weight of methyl vinyl silicone rubber, 300 parts of conductive polyaniline, and 0.5 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 22 hours to obtain a precast rubber mixture that is stealthy in the S band.

[0071] B. Mixing 120 parts by weight of methyl vinyl silicone rubber, 800 parts of conductive polypyrrole, and 2 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 26 hours to obtain a precast rubber mixture that is stealthy to the X-band.

[0072] C. Mixing 110 parts by weight of methyl vinyl silicone rubber, 600 parts of ferrite, and 1.5 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 24 hours to obtain a C-band stealth rubber mixture.

[0073] D. cutting the obtained mixed rubber for S-band stealth, the mixed rubber for X-band stealth, and the mixed rubber for C-band stealth to obtain mixed films for S-band stealth, mixed films for X-band stealth, and mixed films for C-band stealth; stacking the mixed films for S-band stealth, the mixed films for X-band stealth, and mixed films for C-band stealth in sequence in a mold for compression molding and vulcanization to obtain a radar absorbing layer 1;

[0074] The compression vulcanization molding process parameters are as follows: vulcanization temperature is 180°C, vulcanization pressure is 15 MPa, and vulcanization time is 5 min;

[0075] 2) Preparation of wave-transmitting fabric layer 2

[0076] First, the wave-transmitting fabric is cut to obtain a wave-transmitting fabric sheet; then, the wave-transmitting fabric sheet is laid flat on the surface of the radar absorbing layer obtained in step 2, thereby obtaining the wave-transmitting fabric layer 2;

[0077] 3) Preparation of infrared stealth layer 3

[0078] A. In parts by weight, 90 parts of liquid silicone rubber, 15 parts of aluminum powder, 0.5 parts of dispersant, 0.5 parts of leveling agent, 0.3 parts of defoamer, 50 parts of xylene and 1 part of KH560 were added to a paint mixing tank in sequence, and ultrasonic dispersion was performed until uniform dispersion was achieved to obtain an infrared stealth coating;

[0079] B. The infrared stealth coating is applied to the wave-transmitting fabric layer obtained in step 2) by roller coating, and then dried at 140° C. for 2 h to obtain the infrared stealth layer 3.

[0080] In order to further verify the efficacy of the present invention, the inventors conducted relevant tests on the reflectivity and mechanical properties of the stealth material samples obtained in this embodiment. The test results are as follows: the infrared and radar-compatible silicone rubber stealth material prepared in the embodiment of the present invention has a reflectivity of ≤-12dB in the frequency range of 2GHz to 18GHz, an infrared emissivity of 0.273, a tensile strength of 15MPa, an elongation at break of 40%, and a tear strength of 60kN / m.

[0081] Example 3

[0082] An embodiment of the present invention provides an infrared and radar compatible silicone rubber stealth material, which is the same as Example 1 and Example 2 as a whole and also has a three-layer structure, including a radar absorbing layer 1, a wave-transparent fabric layer 2 and an infrared stealth layer 3 stacked in sequence from bottom to top.

[0083] Different from Examples 1 and 2, the radar absorbing layer 1 of this embodiment includes four absorbing layers, which are respectively used for radar stealth for the S band, X band, C band and Ku band. Any one of the absorbing layers is composed of 80 to 120 parts of silicone rubber matrix, 300 to 800 parts of absorbent and 0.5 to 2 parts of vulcanizing agent in parts by weight.

[0084] Specifically, the radar absorbing layer for S-band stealth in this embodiment comprises the following components, by weight: 90 parts methyl vinyl silicone rubber, 450 parts conductive carbon black, and 1 part 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the conductive carbon black has a particle size of 20 μm. The radar absorbing layer for X-band stealth comprises the following components, by weight: 110 parts methyl vinyl silicone rubber, 700 parts silicon carbide, and 0.5 parts 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the silicon carbide has a particle size of 30 μm. The radar absorbing layer for C-band stealth comprises the following components, by weight: 120 parts methyl vinyl silicone rubber, 750 parts graphite, and 1.8 parts 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the graphite has a particle size of 50 μm. The radar absorbing layer for Ku-band stealth comprises the following components, by weight: 105 parts methyl vinyl silicone rubber, 650 parts silicon carbide, and 0.8 parts 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Preferably, the silicon carbide has a particle size of 45 μm.

[0085] In the embodiment of the present invention, the thickness of the wave-transmitting fabric layer 2 is 1 mm.

[0086] In the embodiment of the present invention, the infrared stealth layer 3 comprises the following components, measured by weight: 110 parts liquid silicone rubber, 25 parts aluminum powder, 1.5 parts dispersant, 1 part leveling agent, 0.6 part defoamer, 80 parts tetrahydrofuran, and 2 parts KH550. Preferably, the aluminum powder has a particle size of 15 μm.

[0087] like Figure 1 As shown, the infrared and radar compatible silicone rubber stealth material provided in the embodiment of the present invention is prepared by the following method:

[0088] 1) Preparation of radar absorbing layer 1

[0089] A. Mix 90 parts by weight of methyl vinyl silicone rubber, 450 parts by weight of conductive carbon black, and 1 part by weight of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture. After the precast rubber mixture is allowed to stand for 21 hours, a precast rubber mixture having S-band stealth properties is obtained.

[0090] B. Mixing 110 parts by weight of methyl vinyl silicone rubber, 700 parts of silicon carbide, and 0.5 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 25 hours to obtain a precast rubber mixture having X-band stealth properties.

[0091] C. Mixing 120 parts by weight of methyl vinyl silicone rubber, 750 parts of graphite, and 1.8 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 26 hours to obtain a C-band invisible rubber mixture.

[0092] D. Mixing 105 parts by weight of methyl vinyl silicone rubber, 650 parts of silicon carbide, and 0.8 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane to obtain a precast rubber mixture; and allowing the precast rubber mixture to stand for 23 hours to obtain a Ku-band stealth rubber mixture.

[0093] E. Cutting the obtained S-band stealth rubber mix, X-band stealth rubber mix, C-band stealth rubber mix, and Ku-band stealth rubber mix to obtain S-band stealth mixed film, X-band stealth mixed film, C-band stealth mixed film, and Ku-band stealth mixed film; stacking the S-band stealth mixed film, X-band stealth mixed film, C-band stealth mixed film, and Ku-band stealth mixed film in a mold in sequence for compression molding and vulcanization to obtain a radar absorbing layer 1;

[0094] The compression vulcanization molding process parameters are as follows: vulcanization temperature is 170°C, vulcanization pressure is 10 MPa, and vulcanization time is 15 min;

[0095] 2) Preparation of wave-transmitting fabric layer 2

[0096] First, the wave-transmitting fabric is cut to obtain a wave-transmitting fabric sheet; then, the wave-transmitting fabric sheet is laid flat on the surface of the radar absorbing layer obtained in step 2, thereby obtaining the wave-transmitting fabric layer 2;

[0097] 3) Preparation of infrared stealth layer 3

[0098] A. In parts by weight, 110 parts of liquid silicone rubber, 25 parts of aluminum powder, 1.5 parts of dispersant, 1 part of leveling agent, 0.6 parts of defoaming agent, 80 parts of tetrahydrofuran and 2 parts of KH550 were added to a beaker in sequence, and ultrasonic dispersion was performed until uniform dispersion was achieved to obtain an infrared stealth coating;

[0099] B. The infrared stealth coating is applied to the wave-transmitting fabric layer obtained in step 2) by roller coating, and then dried at 160° C. for 0.5 h to obtain the infrared stealth layer 3.

[0100] In order to further verify the effectiveness of the present invention, the inventors conducted relevant tests on the reflectivity and mechanical properties of the stealth material samples obtained in this embodiment. The test results are as follows: the infrared and radar-compatible silicone rubber stealth material prepared in the embodiment of the present invention has a reflectivity of ≤-14dB in the frequency range of 2GHz to 18GHz, an infrared emissivity of 0.325, a tensile strength of 15MPa, an elongation at break of 30%, and a tear strength of 65kN / m.

[0101] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0102] It should be understood that the present invention is not limited to the above description and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. An infrared and radar compatible stealth material containing silicone rubber, characterized in that: The stealth material is composed of a radar absorbing layer, a wave-transmitting fabric layer and an infrared stealth layer stacked in sequence from bottom to top; The radar absorbing layer comprises a plurality of stacked absorbing layers, and at least two of the absorbing layers are radar-invisible for different bands, and any one of the radar absorbing layers comprises a silicone rubber matrix; Any one of the radar absorbing layers is made of the following components by weight: 80 to 120 parts of a silicone rubber matrix, 300 to 800 parts of an absorbent, and 0.5 to 2 parts of a vulcanizing agent; The infrared stealth layer is made of the following components by weight: 90 to 110 parts of adhesive, 15 to 25 parts of aluminum powder, 0.5 to 1.5 parts of dispersant, 0.5 to 1 part of leveling agent, 0.3 to 0.6 parts of defoaming agent, 50 to 80 parts of diluent and 1 to 2 parts of coupling agent; The adhesive is liquid silicone rubber.

2. The infrared and radar compatible silicone rubber stealth material according to claim 1, characterized in that: The absorbent includes at least one of ferrite, carbonyl iron, iron silicon chromium, conductive carbon black, graphite, conductive polyaniline, conductive polypyrrole, and silicon carbide, and the particle size of the absorbent is 3 μm to 70 μm.

3. The infrared and radar compatible stealth material containing silicone rubber according to claim 1, characterized in that: The wave-transmitting fabric layer is made of glass fiber cloth with a mesh structure, and the thickness of the wave-transmitting fabric layer is 0.03 mm to 1 mm.

4. The infrared and radar compatible stealth material containing silicone rubber according to claim 1, characterized in that: The diluent includes at least one of iron n-octane, n-pentane, xylene, and tetrahydrofuran.

5. The infrared and radar compatible silicone rubber stealth material according to claim 1, characterized in that: The particle size of the aluminum powder is 10 μm to 15 μm.

6. The infrared and radar compatible silicone rubber stealth material according to claim 1, characterized in that: The coupling agent includes one of KH550, KH560, and KH570.

7. A method for preparing an infrared and radar compatible stealth material containing silicone rubber according to any one of claims 1 to 6, comprising the following steps: Step 1: Prepare radar absorbing layer In parts by weight, 80 to 120 parts of a silicone rubber matrix, 300 to 800 parts of an absorbent, and 0.5 to 2 parts of a vulcanizing agent are mixed and kneaded in different proportions to obtain a plurality of different mixed preformed rubbers; the various mixed preformed rubbers are allowed to stand for a set time to obtain a plurality of different mixed rubbers; the various mixed rubbers are then cut to obtain a plurality of different mixed film sheets; the various mixed film sheets are stacked in a mold and subjected to compression molding and vulcanization to obtain a radar absorbing layer comprising multiple absorbing layers, which is used to provide radar stealth for different bands; Step 2: Prepare the wave-transparent fabric layer First, the wave-transmitting fabric is cut to obtain a wave-transmitting fabric sheet; then, the wave-transmitting fabric sheet is laid flat on the surface of the radar absorbing layer obtained in step 1, thereby obtaining a wave-transmitting fabric layer; Step 3: Prepare infrared stealth layer In parts by weight, 90 to 110 parts of an adhesive, 15 to 25 parts of aluminum powder, 0.5 to 1.5 parts of a dispersant, 0.5 to 1 part of a leveling agent, 0.3 to 0.6 parts of a defoaming agent, 50 to 80 parts of a diluent, and 1 to 2 parts of a coupling agent are sequentially added into a container, and ultrasonic dispersion is performed until uniform dispersion is achieved to obtain an infrared stealth coating. Finally, the infrared stealth coating is applied to the wave-transparent fabric layer obtained in step 2 by a roller coating method, and after drying, an infrared stealth layer is obtained.

8. The preparation method according to claim 7, characterized in that In step 1, the compression vulcanization molding process parameters are as follows: vulcanization temperature is 170° C. to 180° C., vulcanization pressure is 10 MPa to 15 MPa, and vulcanization time is 5 min to 15 min; In step 3, the drying process parameters are as follows: temperature is 140° C. to 160° C., and drying time is 0.5 h to 2 h.

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