A high temperature resistant ceramic fiber reinforced resin matrix composite material for radar antenna cover and preparation method thereof

Abstract

The present invention discloses a high temperature resistant ceramic fiber reinforced resin-based composite material for a radar antenna cover and a preparation method thereof, and belongs to the technical field of composite materials. The ceramic fiber reinforced resin-based composite material adopted by the present invention has the advantages of high temperature resistance, low high temperature ablation rate, no moisture absorption, high strength, etc., so that the prepared radar antenna cover has the characteristics of high working temperature, high strength, corrosion resistance, low cost, etc. Moreover, the ceramic fiber composite rib is set as a spiral structure sandwiched between a ceramic fiber reinforced resin-based composite plate 1 and a ceramic fiber reinforced resin-based composite plate 2, and the interlayer is set as a spiral structure, which further increases the tensile strength and high temperature resistance.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite materials, and in particular relates to a high-temperature resistant ceramic fiber reinforced resin-based composite material for a radar antenna cover and a preparation method thereof. Background Art

[0002] The radar antenna cover is a window for electromagnetic waves. Its function is to protect the antenna and prevent the environment from affecting and interfering with the working state of the radar antenna, thereby reducing the power driving the antenna to operate, improving its working reliability, and ensuring that the radar antenna works around the clock.

[0003] As radar gradually develops in the direction of wide bandwidth and high power, the materials used for certain aircraft antenna covers must not only meet the wave transmission requirements, but also maintain sufficient mechanical strength and appropriate elastic modulus at high temperatures, and need to have good thermal shock resistance and heat resistance.

[0004] In order to meet the needs of aircraft research and development, high temperature radomes have become the main trend in the development of radome technology. Ceramic fiber has the advantages of light weight, high temperature resistance, good thermal stability, low thermal conductivity, small specific heat, and mechanical vibration resistance. Ceramic fiber reinforced resin-based composite materials can greatly improve the strength of resin-based materials while maintaining their excellent performance, and can be used to prepare high temperature resistant radomes. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0007] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing a high temperature resistant ceramic fiber reinforced resin-based composite material for a radar antenna cover.

[0008] In order to solve the above technical problems, the present invention provides the following technical solutions, including:

[0009] Inorganic nanopowder, silane coupling agent and resin are uniformly mixed to prepare modified inorganic resin, and the modified inorganic resin and ceramic fiber are stirred, dispersed and uniformly mixed, and then molded and cured to obtain a high-temperature resistant ceramic fiber reinforced resin-based composite material;

[0010] Wherein, the mass ratio of the modified inorganic resin to the ceramic fiber is 1-3:2-4.

[0011] As a preferred solution of the method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover of the present invention, the addition amount of the inorganic nano powder is 2-6%; the addition amount of the silane coupling agent is 0.1-1%.

[0012] As a preferred solution of the method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover described in the present invention, the inorganic nano powder is nano silicate, including nano lithium silicate, nano calcium silicate and nano aluminum silicate.

[0013] As a preferred scheme for the preparation method of the high-temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover described in the present invention, the silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, aminosilane, epoxysilane, thiosilane, methacryloxysilane, vinylsilane, ureasilane or isocyanatesilane.

[0014] As a preferred embodiment of the method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover described in the present invention, the ceramic fiber includes one or more of silicon carbide fiber, carbon fiber, aluminum silicate fiber, quartz fiber or alumina fiber.

[0015] As a preferred embodiment of the method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover described in the present invention, the rotation speed of the stirring and dispersing is 1000-2000 r / min; the temperature of the molding and curing is 100-150°C.

[0016] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a high temperature resistant ceramic fiber reinforced resin based composite material for a radar antenna cover.

[0017] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a high-temperature ceramic fiber radar antenna cover, the radar antenna cover comprising a protective cover and a base, the protective cover is composed of protective plates connected to each other, the protective plate is provided with a three-layer structure, which is a ceramic fiber composite rib sandwiched between ceramic fiber reinforced resin-based composite plates;

[0018] Wherein, the ceramic fiber reinforced resin-based composite plate is prepared from the plate-shaped ceramic fiber reinforced resin-based composite material.

[0019] As a preferred solution of the high-temperature ceramic fiber radar antenna cover of the present invention, the protective cover is configured as a spherical structure, and the bottom of the protective cover is fixed on the base.

[0020] As a preferred solution of the high temperature ceramic fiber radar antenna cover of the present invention, the protection plate is configured as a regular hexagonal structure with a curvature; and the ceramic fiber composite ribs are a spiral structure.

[0021] Beneficial effects of the present invention:

[0022] The high-temperature ceramic fiber radar antenna cover prepared by our invention uses a ceramic fiber reinforced resin-based composite material with the advantages of high temperature resistance, low high-temperature ablation rate, no moisture absorption, and high strength, so that the radar antenna cover has the characteristics of high working temperature, high strength, corrosion resistance, and low cost. In addition, the ceramic fiber composite ribs are set as a spiral structure sandwiched between two ceramic fiber reinforced resin-based composite plates, and the interlayers are set as a spiral structure, which further increases the tensile strength and high temperature resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0024] Figure 1 The figure is a schematic diagram of a high temperature ceramic fiber radar antenna cover made by the present invention.

[0025] Figure 2 It is a schematic diagram of the cross-sectional structure of the plate of the present invention. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0027] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0028] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0029] The raw materials used in the present invention are all commercially available unless otherwise specified.

[0030] The performance of the material prepared in the embodiment of the present invention was tested as follows:

[0031] 1. Mechanical properties test

[0032] (1) Tensile strength: An electronic universal testing machine is used to test in accordance with GB / T2567-2008. The sample is clamped so that the central axis of the sample is consistent with the alignment line of the upper and lower clamps. The test is carried out at room temperature with a loading speed of 10 mm / min. When the sample breaks, the ratio of the tensile force applied to the sample to the fracture surface area of ​​the sample is the tensile strength of the sample. The average tensile strength of each group of test samples is taken as the tensile strength value.

[0033] (2) Bending strength test method (GB / T2567-2008): Process the spline according to the size requirements to ensure that there are no obvious defects on the surface. Use a vernier caliper to measure the width and thickness of the specimen at three points near the center of the span, and take the arithmetic mean. Enter the spline size data into the software interface, place the spline on the bracket according to the span L requirements, and slowly adjust the position of the testing machine pressure head to 1mm away from the middle of the specimen. Adjust the pressure head loading speed to 10mm / min on the computer interface, click the zero button in the software interface to ensure that the pressure load value is zero, click the start button, and load evenly and continuously at the specified speed until it is destroyed. Record the destruction load or maximum load value, and take the average tensile strength of each group of test splines as the tensile strength value.

[0034] 2. Ablation resistance test

[0035] According to the ablation test of ablation materials in GJB 323A-1996, an oxygen-acetylene flame is blown vertically onto the sample to perform ablation test on the material.

[0036] Sample: Diameter: 30±0.2mm, thickness 19±0.2mm. The sample surface should be smooth and flat, and the parallelism of the two planes should not exceed 0.1mm.

[0037] Test method:

[0038] (1) Fix the sample steel plate, open the main valves of the oxygen and acetylene cylinders, adjust the pressure reducing valves, and adjust the oxygen and acetylene cylinders to the preset pressures.

[0039] (2) Open the two pipeline valves of the combustion gun, and then adjust the gas flow rate of the flow meter, the oxygen flow rate / acetylene flow rate is 1.35.

[0040] (3) Ignite the nozzle of the combustion gun, adjust the oxygen valve of the combustion gun to a blue flame, fix the distance between the flame and the steel plate to 2 cm and 3.5 cm respectively, and start the ablation test.

[0041] (4) Test the burn-through time and surface temperature of the steel plate coated with basalt fiber coating.

[0042] Example 1

[0043] This embodiment provides a method for preparing a ceramic fiber reinforced resin-based composite material, specifically:

[0044] (1) 4% inorganic nano-lithium silicate powder, 0.6% γ-aminopropyltriethoxysilane (KH550), and 95.4% epoxy resin are mixed evenly to prepare a modified inorganic resin.

[0045] (2) Weighing the modified inorganic resin and quartz fiber in a mass ratio of 2:3, stirring and dispersing them at room temperature using a high-speed disperser at a speed of 1500 r / min until the two are evenly mixed;

[0046] (3) Clean the mold with anhydrous ethanol and dry it;

[0047] (4) The mixture is evenly spread into a mold, and the mold is placed in a flat vulcanizer and cured at a temperature of 120° C. to obtain a ceramic fiber reinforced resin-based composite material.

[0048] Example 2

[0049] The difference between this embodiment and embodiment 1 is that the ratio of inorganic resin to quartz fiber is adjusted to 1:1, and the rest of the preparation process is the same as that of embodiment 1 to obtain a ceramic fiber reinforced resin-based composite material.

[0050] Example 3

[0051] The difference between this embodiment and embodiment 1 is that the ratio of inorganic resin to quartz fiber is adjusted to 3:7, and the rest of the preparation process is the same as that of embodiment 1 to obtain a ceramic fiber reinforced resin-based composite material.

[0052] Example 4

[0053] The difference between this embodiment and embodiment 1 is that the ratio of inorganic resin to quartz fiber is adjusted to 1:4, and the rest of the preparation process is the same as that of embodiment 1 to obtain a ceramic fiber reinforced resin-based composite material.

[0054] The performance of the material prepared in the above embodiment was tested, and the comparison results with those in Example 1 are shown in Table 1.

[0055] Table 1

[0056]

[0057] It can be seen from the above table that adjusting the ratio of inorganic silicone resin to quartz fiber has a significant effect on the performance of ceramic fiber reinforced resin-based composite panels. This is because the mechanical properties of composite materials mainly depend on quartz fiber. Too high a ratio of inorganic resin to quartz fiber will result in the quartz fiber not having a reinforcing effect, while too low a ratio will result in the quartz fiber being difficult to solidify with the resin into a whole material, resulting in poor mechanical properties. The more quartz fiber added, the better. When too much quartz fiber is added, the fiber will be wrapped in resin, resulting in poor mechanical properties. According to the results in the above table, the best technical effect can be obtained when the ratio of inorganic resin to quartz fiber in the present invention is 3:2.

[0058] Example 5

[0059] This embodiment provides a radar radome made of high temperature resistant ceramic fiber reinforced resin matrix composite material. The radome includes a protective cover 100 and a base 300.

[0060] The protective cover 100 is designed as a spherical structure, which not only provides all-round protection but also helps to reduce the scattering of radar signals. The bottom of the protective cover 100 is fixed on the base 300, and the base 300 provides a stable support for the protective cover. The protective cover 100 is composed of a plurality of protective plates 200 connected to each other to form a protective layer with a stable structure.

[0061] Each protective plate 200 has a three-layer structure, including two layers of ceramic fiber reinforced resin-based composite plates 201 and ceramic fiber composite ribs 202 sandwiched between them. This structural design improves the strength and heat resistance of the protective cover, allowing it to maintain performance in a high temperature environment.

[0062] The ceramic fiber reinforced resin-based composite plate 201 is prepared by using the high temperature resistant ceramic fiber reinforced resin-based composite material of the present invention, and has excellent mechanical properties and high temperature resistance characteristics.

[0063] In order to further enhance the structural strength of the protective cover, the protective plate 200 is designed as a regular hexagonal structure with a curvature. This structure is not only beautiful, but also can evenly disperse the external force received, thereby improving the overall impact resistance.

[0064] The ceramic fiber composite ribs 202 are sandwiched between two layers of ceramic fiber reinforced resin-based composite plates in a spiral structure. This design helps to improve the tensile strength and shear resistance of the protective cover, making it less likely to deform or be damaged when subjected to external impact.

[0065] In summary, the radar antenna cover of this embodiment can maintain stable performance in a high temperature environment through its unique structural design, while providing efficient radar signal protection.

[0066] The high-temperature ceramic fiber radar antenna cover prepared by the invention adopts a ceramic fiber reinforced resin-based composite material with the advantages of high temperature resistance, low high-temperature ablation rate, no moisture absorption, high strength, etc., so that the prepared radar antenna cover has the characteristics of high operating temperature, high strength, corrosion resistance, low cost, etc.

[0067] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a high temperature resistant ceramic fiber reinforced resin-based composite material for a radar antenna cover, characterized in that: include, Inorganic nanopowder, silane coupling agent and resin are uniformly mixed to prepare modified inorganic resin, and the modified inorganic resin and ceramic fiber are stirred, dispersed and uniformly mixed, and then molded and cured to obtain a high-temperature resistant ceramic fiber reinforced resin-based composite material; Wherein, the mass ratio of the modified inorganic resin to the ceramic fiber is 1-3:2-4.

2. The method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover according to claim 1, characterized in that: The addition amount of the inorganic nano powder is 2-6%; the addition amount of the silane coupling agent is 0.1-1%.

3. The method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover according to claim 2, characterized in that: The inorganic nano powder is nano silicate, including nano lithium silicate, nano calcium silicate and nano aluminum silicate.

4. The method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover according to claim 2, characterized in that: The silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, aminosilane, epoxysilane, thiosilane, methacryloxysilane, vinylsilane, ureasilane or isocyanatesilane.

5. The method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover according to claim 1, characterized in that: The ceramic fiber includes one or more of silicon carbide fiber, carbon fiber, aluminum silicate fiber, quartz fiber or aluminum oxide fiber.

6. The method for preparing the high temperature resistant ceramic fiber reinforced resin-based composite material for radar antenna cover according to claim 1, characterized in that: The rotation speed of the stirring and dispersing is 1000-2000 r / min; the temperature of the molding and curing is 100-150°C.

7. A high temperature resistant ceramic fiber reinforced resin based composite material for a radar antenna cover prepared by the preparation method according to any one of claims 1 to 6.

8. A radar antenna cover, characterized in that: The radar antenna cover comprises a protective cover (100) and a base (300), wherein the protective cover (100) is composed of protective plates (200) connected to each other, and the protective plates (200) are provided with a three-layer structure, which includes two layers of ceramic fiber reinforced resin-based composite plates (201) and ceramic fiber composite ribs (202) sandwiched therebetween; Wherein, the ceramic fiber reinforced resin-based composite plate (201) is prepared from the plate-shaped ceramic fiber reinforced resin-based composite material according to claim 9.

9. The radome according to claim 8, characterized in that: The protective cover (100) is configured as a spherical structure, and the bottom of the protective cover (100) is fixed on the base (300).

10. The radome according to claim 9, characterized in that: The protection plate (200) is configured as a regular hexagonal structure with a curvature; and the ceramic fiber composite rib (202) is a spiral structure.

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