Curved surface adaptive hollow carbon fiber tube array structure and manufacturing method thereof

Abstract

The application provides a curved surface adaptive hollow carbon fiber pipe array structure and a manufacturing method thereof. The curved surface adaptive hollow carbon fiber pipe array structure comprises a plurality of zero-expansion self-heating grid-shaped pipe structures, and the grid-shaped pipe structure is composed of a plurality of zero-expansion heating wire bundles. The zero-expansion heating wire bundle is composed of a positive thermal expansion coefficient resin-based composite material, a negative thermal expansion coefficient resin-based composite material and a heating film. The pipe array structure adopts an integral co-curing mode to realize the connection of each part, reduces the weight of the pipe array structure, and reduces the forming cost and time. In addition, since the heating structure is arranged in each pipe, the temperature of the structure can be accurately controlled according to the requirement, the temperature change of the structure can be controlled in a very small range, the thermal deformation of the structure is greatly reduced, and the environmental adaptability of the pipe array structure is improved.

Description

Technical Field

[0001] This invention belongs to the field of composite material molding technology, specifically relating to a curved surface adaptive hollowed-out carbon fiber tube array structure and its manufacturing method. Background Technology

[0002] Antenna reflectors, as core passive components in radio communication, radar detection, and radio astronomy, play a crucial role in aerospace, satellite communication, and precision radar applications. These devices must maintain micron-level surface precision under extreme mechanical environments (such as emission vibrations) and thermal environments (such as alternating temperature differences in space). Sandwich structures, with their superior specific stiffness characteristics, have become the preferred solution for resolving these challenges and constructing high-performance satellite antenna reflectors.

[0003] However, in-depth research into relevant technologies both domestically and internationally has revealed that the thermal deformation of sandwich structures is primarily limited by the coefficient of thermal expansion (CTE) of the core material and the significant temperature difference in the space environment. Currently, conventional low-thermal-expansion core materials (such as carbon fiber honeycomb and carbon fiber grids) can control the CTE to within 1×10⁻⁶. -7 While the temperature is in the range of / ℃, there are still significant drawbacks: First, the material itself has high stiffness, making it difficult to achieve a perfect fit with the complex curved skin of the reflector, and it is easy to generate large residual stress at the bonding interface; second, traditional passive structures lack active thermal control capabilities, resulting in significant temperature differences inside the structure, which in turn leads to thermal deformation that cannot be ignored.

[0004] To address the aforementioned technical bottlenecks, this invention proposes a curved adaptive hollowed-out carbon fiber tube array structure. This structure not only further reduces the coefficient of thermal expansion to 1×10⁻⁶ -8 It is on the order of / ℃ and innovatively integrates active temperature control, fundamentally solving the problem of thermal stability of high-precision reflectors. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a curved adaptive hollowed-out carbon fiber tube array structure and its fabrication method.

[0006] According to the present invention, a curved adaptive hollow carbon fiber tube array structure includes: multiple zero-expansion self-heating mesh-like tube structures; The zero-expansion self-heating grid-like tubular structures are arranged vertically in an array to form a whole.

[0007] Preferably, the zero-expansion self-heating grid-like tubular structures are integrated by heating the resin matrix through an internal heating film within the tubing to cure it.

[0008] Preferably, the zero-expansion self-heating mesh-like tubular structure is composed of several zero-expansion heating wire bundles; the zero-expansion heating wire bundles are composed of a resin-based composite material with a positive coefficient of thermal expansion, a resin-based composite material with a negative coefficient of thermal expansion, and a heating film.

[0009] Preferably, the reinforcing component of the resin-based composite material with positive thermal expansion coefficient is fiber, wherein the fiber includes glass fiber, Kevlar fiber, quartz fiber or basalt fiber; The reinforcement of the resin-based composite material with negative thermal expansion coefficient is fiber, wherein the fiber includes carbon fiber or aramid fiber; The heating element material of the heating film is made of nickel-chromium alloy, constantan, graphene or carbon nanotubes, and the insulating material is made of polyimide, silicone rubber or polyester film.

[0010] Preferably, a zero-expansion heating fiber bundle is formed by laying a layer of positive expansion coefficient resin composite fiber, a layer of negative expansion coefficient resin composite fiber, a heating film, a layer of negative expansion coefficient resin composite fiber, and a layer of positive expansion coefficient resin composite fiber on the platform.

[0011] A method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure according to the present invention includes: Composite fiber bundles are formed by laying a layer of resin composite fiber with positive expansion coefficient, a layer of resin composite fiber with negative expansion coefficient, a heating film, a layer of resin composite fiber with negative expansion coefficient, and a layer of resin composite fiber with positive expansion coefficient on the platform. Mix components A and B of the room-temperature curing resin at a ratio of 2:5 until homogeneous, and then degas under vacuum. The composite material filaments are immersed in the mixed resin, and after being removed, the excess resin on the composite material filaments is removed by methods such as extrusion. Apply a release agent to the outer surface of the core mold; The resin-impregnated composite material filament bundles are wound clockwise in a spiral manner onto the mandrel; then the resin-impregnated composite material filament bundles are wound counterclockwise in a spiral manner onto the mandrel, forming a mesh-like filament bundle on the mandrel. The core mold, which is wrapped with resin-impregnated composite material filaments, is fixed to the adhesive assembly fixture by screws in sequence, ensuring that the outer winding layers of the core mold are tangent to each other, and the external wiring of the heating film is connected to the power controller. Turn on the power controller to heat the wound filament bundle and control the filament bundle temperature to cure by measuring the filament bundle temperature with a thermocouple; After curing is complete, remove the screws that fix the core mold, remove the tube array structure containing the core mold, and remove the core mold by squeezing the tube array structure to increase its inner diameter.

[0012] Preferably, the ratio of the positive thermal expansion coefficient resin composite material, the negative thermal expansion coefficient resin composite material, and the heating film thickness is calculated based on the stiffness and thermal expansion coefficient of the positive thermal expansion coefficient resin composite material, the negative thermal expansion coefficient resin composite material, and the heating film.

[0013] Preferably, the room-temperature curing resin consists of two components, A and B, with a curing temperature of 100°C. After medium-temperature curing, the degree of curing of the resin is 50% to 60%. The medium-temperature cured resin is then subjected to a second curing at 180°C, after which the degree of curing of the resin is 95% to 100%.

[0014] Preferably, the density of the curved adaptive hollow carbon fiber tube array structure is ≤10kg / m³. 3 .

[0015] Preferably, the coefficient of thermal expansion of the curved adaptive hollow carbon fiber tube array structure is ≤1×10⁻⁶. -8 / ℃.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The tube array forming process of the present invention does not have any external heat source, which breaks the status quo of the existing technology of using external heat source heating for lattice structure, and greatly reduces the energy consumption of forming. 2. The tube array structure of the present invention adopts a mesh structure, which greatly reduces demolding damage and improves the adaptability of the tube array structure to curved skin. Attached Figure Description

[0017] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of a curved adaptive hollow carbon fiber tube array structure.

[0018] Figure 2 A partially enlarged schematic diagram of a self-heating, grid-like tubular structure with zero expansion.

[0019] Figure 3 This is a structural diagram showing the location of the power line for the heating film.

[0020] Figure 4 This is a structural diagram of an uncured curved adaptive hollow carbon fiber tube array structure and an adhesive assembly mold containing a core mold.

[0021] Figure 5 This is a schematic diagram of the adhesive bonding assembly mold (excluding the core mold) and the core mold structure.

[0022] The diagram shows: Detailed Implementation

[0023] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0024] To address the shortcomings of existing technologies, the purpose of this invention is to provide a curved surface adaptive hollow carbon fiber tube array structure and its fabrication method. This invention enables the manufacture of a curved surface adaptive hollow carbon fiber tube array structure, which, compared to existing honeycomb structures, offers advantages such as lighter weight, stronger adaptability to curved surfaces, ultra-low coefficient of thermal expansion, and self-heating capability.

[0025] The present invention provides a curved adaptive hollowed-out carbon fiber tube array structure 1, as shown in the figure. Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, it includes several zero-expansion self-heating mesh-like tubular structures 2. The zero-expansion self-heating mesh-like tubular structures 2 are arranged vertically in an array, and the zero-expansion self-heating mesh-like tubular structures 2 are connected to each other by heating the resin matrix through an internal heating film to form a whole; the zero-expansion self-heating mesh-like tubular structure 2 is mainly composed of a resin composite material with a positive coefficient of thermal expansion 3, a resin composite material with a negative coefficient of thermal expansion 4, and a heating film 5.

[0026] The array is a circular array structure.

[0027] The zero-expansion self-heating mesh-like tubular structure 2 is composed, or mainly composed, of a layer of 0.8mm thick M55 carbon fiber composite material (positive thermal expansion coefficient resin composite material 3), a layer of 0.2mm thick Kevlar fiber composite material (negative thermal expansion coefficient resin composite material 4), a layer of 0.5mm thick graphene heating film (heating film 5), another layer of 0.2mm thick Kevlar fiber composite material (negative thermal expansion coefficient resin composite material 4), and a third layer of 0.8mm thick M55 carbon fiber composite material (positive thermal expansion coefficient resin composite material 3). The outer diameter of the tube is 40mm, and the height is 60mm.

[0028] Example 1 This invention also provides a method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure, comprising the following steps: Mandrels are made from Invar steel according to the actual pipe fitting dimensions; Composite fiber bundles are formed by laying a layer of resin composite fiber with positive expansion coefficient, a layer of resin composite fiber with negative expansion coefficient, a heating film, a layer of resin composite fiber with negative expansion coefficient, and a layer of resin composite fiber with positive expansion coefficient on the platform. Mix components A and B of the room-temperature curing resin at a ratio of 2:5 until homogeneous, and then degas under vacuum. The composite material filaments are immersed in the mixed resin, and after being removed, the excess resin on the composite material filaments is removed by methods such as extrusion. Apply paraffin wax to the outer surface of the core mold; The resin-impregnated composite material filaments are spirally wound clockwise onto the mandrel with a pitch of 60 mm. This process is repeated, with the gap between two bundles being one-sixth of the circumference. The remaining four resin-impregnated composite material filaments are then wound in the same manner. Next, the resin-impregnated composite material filaments are spirally wound counterclockwise onto the mandrel with a pitch of 60 mm. This process is repeated, with the gap between two bundles being one-sixth of the circumference. The remaining four resin-impregnated composite material filaments are then wound in the same manner, forming a mesh-like filament bundle on the mandrel. The core mold, which is wrapped with resin-impregnated composite material filaments, is fixed to the adhesive assembly fixture by screws in sequence, ensuring that the outer winding layers of the core mold are tangent to each other, and the external wiring of the heating film is connected to the power controller. Turn on the power controller to heat the wound wire bundle and control the wire bundle temperature at 180°C for 24 to 48 hours by measuring the wire bundle temperature with a thermocouple. After curing is complete, remove the screws that fix the core mold, and then remove the tube array structure containing the core mold. Since the tube array structure is a grid structure with weak overall rigidity, the core mold is removed by squeezing the tube array structure to increase its inner diameter.

[0029] The performance test results of the curved adaptive hollow carbon fiber tube array structure prepared in this embodiment are as follows: density 8.9 kg / m³ 3 The coefficient of thermal expansion is 0.3 × 10⁻⁶. -8 / ℃, and its heating power is 120W.

[0030] Comparative Example 1 Step 1: Cut the M60J carbon fiber cyanate hot-melt prepreg according to the specific shape of the composite material tube; Step 2: Apply release agent to the mold. According to the thickness of the composite material tube, wrap the cut M55J carbon fiber cyanate hot melt prepreg onto the rod mold in sequence. Wrap the entire mold with a vacuum bag and remove the air from the bag to ensure that the room temperature prepreg is subjected to a vacuum pressure of 0.1MPa. Cure at 180℃ for 24 hours.

[0031] Step 3: Remove the cured composite material tube from the mold and remove the excess material from the edges to obtain the composite material tube.

[0032] Step 4: Sand the adhesive surface of the composite material tube with sandpaper and apply a layer of medium-temperature curing adhesive film to the adhesive surface.

[0033] Step 5: Place the composite material tubes evenly on the flat plate, and apply pressure to the tubes around the perimeter with the surrounding strips to ensure that all the adhesive surfaces of the tubes are firmly bonded. Step 6: Place the fixed tube array into the molding mold for high-temperature curing and shaping, and then remove it from the mold.

[0034] The performance test results of the tube array structure prepared in this comparative example are as follows: density 40.1 kg / m³ 3 The coefficient of thermal expansion is 2.5 × 10⁻⁶. -7 / ℃.

[0035] The main difference between Comparative Example 1 and Example 1 is that Comparative Example 1 has a closed tubular structure, which has a higher density than the hollow structure of Example 1. Comparative Example 1 has no active temperature control capability and no heating capability itself; while Example 1 has a heating power of 120W and can actively control the temperature.

[0036] By comparing Comparative Example 1 with Example 1, it can be seen that the present invention can effectively reduce the structural weight, and at the same time, it can actively control the temperature to ensure that the temperature change of the entire structure is small, thereby reducing the overall thermal deformation under extreme temperature conditions.

[0037] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0038] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A curved adaptive hollowed-out carbon fiber tube array structure, characterized in that, include: Multiple zero-expansion self-heating mesh-like tubular structures; The zero-expansion self-heating grid-like tubular structures are arranged vertically in an array to form a whole.

2. The curved adaptive hollowed-out carbon fiber tube array structure according to claim 1, characterized in that, Each zero-expansion self-heating grid-like tubular structure is integrated with the resin matrix after being heated and cured by the heating film inside the tubular components.

3. The curved adaptive hollowed-out carbon fiber tube array structure according to claim 1, characterized in that, The zero-expansion self-heating mesh-like tubular structure is composed of several zero-expansion heating wire bundles; the zero-expansion heating wire bundles are composed of resin-based composite materials with positive thermal expansion coefficients, resin-based composite materials with negative thermal expansion coefficients, and heating films.

4. The curved adaptive hollowed-out carbon fiber tube array structure according to claim 3, characterized in that, The positive thermal expansion coefficient resin-based composite material is reinforced with fibers, including glass fibers, Kevlar fibers, quartz fibers, or basalt fibers. The reinforcement of the resin-based composite material with negative thermal expansion coefficient is fiber, wherein the fiber includes carbon fiber or aramid fiber; The heating element material of the heating film is made of nickel-chromium alloy, constantan, graphene or carbon nanotubes, and the insulating material is made of polyimide, silicone rubber or polyester film.

5. The curved adaptive hollowed-out carbon fiber tube array structure according to claim 3, characterized in that, A zero-expansion heating fiber bundle is formed by laying a layer of positive expansion coefficient resin composite fiber, a layer of negative expansion coefficient resin composite fiber, a layer of heating film, a layer of negative expansion coefficient resin composite fiber, and a layer of positive expansion coefficient resin composite fiber on the platform.

6. A method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure, characterized in that, include: Composite fiber bundles are formed by laying a layer of resin composite fiber with positive expansion coefficient, a layer of resin composite fiber with negative expansion coefficient, a heating film, a layer of resin composite fiber with negative expansion coefficient, and a layer of resin composite fiber with positive expansion coefficient on the platform. Mix components A and B of the room-temperature curing resin at a ratio of 2:5 until homogeneous, and then degas under vacuum. The composite material filaments are immersed in the mixed resin, and after being removed, the excess resin on the composite material filaments is removed by methods such as extrusion. Apply a release agent to the outer surface of the core mold; The resin-impregnated composite material filament bundles are wound clockwise in a spiral manner onto the mandrel; then the resin-impregnated composite material filament bundles are wound counterclockwise in a spiral manner onto the mandrel, forming a mesh-like filament bundle on the mandrel. The core mold, which is wrapped with resin-impregnated composite material filaments, is fixed to the adhesive assembly fixture by screws in sequence, ensuring that the outer winding layers of the core mold are tangent to each other, and the external wiring of the heating film is connected to the power controller. Turn on the power controller to heat the wound filament bundle and control the filament bundle temperature to cure by measuring the filament bundle temperature with a thermocouple; After curing is complete, remove the screws that fix the core mold, remove the tube array structure containing the core mold, and remove the core mold by squeezing the tube array structure to increase its inner diameter.

7. The method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure according to claim 6, characterized in that, The ratio of the positive thermal expansion coefficient resin composite material, the negative thermal expansion coefficient resin composite material, and the heating film thickness is calculated based on the stiffness and thermal expansion coefficient of the positive thermal expansion coefficient resin composite material, the negative thermal expansion coefficient resin composite material, and the heating film.

8. The method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure according to claim 6, characterized in that, The room-temperature curing resin consists of two components, A and B, with a curing temperature of 100°C. After medium-temperature curing, the degree of curing of the resin is 50% to 60%. The medium-temperature cured resin is then subjected to a second curing at 180°C, after which the degree of curing of the resin is 95% to 100%.

9. The method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure according to claim 6, characterized in that, The density of the curved adaptive hollow carbon fiber tube array structure is ≤10kg / m³. 3 .

10. The method for fabricating a curved adaptive hollowed-out carbon fiber tube array structure according to claim 6, characterized in that, Curved adaptive hollow carbon fiber tube array structure has a thermal expansion coefficient of ≤1×10 -8 / ℃.

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