Forming method of structure and function integrated test cabinet skin

Abstract

The invention discloses a forming method of a structure and function integrated test cabinet skin in the technical field. Comprising the following steps that (1) main skin forming is conducted, specifically, an outer skin layer, a damping layer and an inner skin layer are adopted, the outer skin layer and the inner skin layer are both made of carbon fiber prepreg, the damping layer is made of damping prepreg, paving is conducted from outside to inside, after paving is completed, the main skin is subjected to high-temperature and high-pressure curing forming in an autoclave, and after demolding, cutting is conducted to obtain the main skin; (2) forming an opening cover plate, paving by adopting a flat die which is the same as the main body skin in structural process, and forming mounting holes in the periphery of the opening cover plate by using processing equipment; the method comprises the following steps of (1) arranging a hole on a main body skin, (2) arranging a hole on the main body skin, (3) forming the hole on the main body skin by using an opening cover plate as a transfer template, and (4) installing the opening cover plate, and installing the opening cover plate on the main body skin by using a fastener, thereby solving the problem that the weight of a conventional metal cabinet is large, and enabling the skin to have a vibration reduction effect while having bearing structural strength.

Description

Technical Field

[0001] The present invention relates to the technical field of composite products, and in particular to a space station test cabinet. Background Art

[0002] At present, all countries are vigorously developing the aerospace industry, especially SpaceX's rocket recovery technology and the successful launch of Starlink. More and more private enterprises are developing and embarking on the road of aerospace, which has also made the unattainable aerospace technology more and more popular among the people and on the road of business. In view of the extreme environment in space, there are extremely high requirements for the raw materials of artificial celestial bodies and spacecraft that can be launched into the earth's atmosphere. According to the rocket, it takes about 50kg of energy to launch 1kg of weight, so the reduction of material weight during the space launch is extremely important for the use of launch energy. In addition, the vibration during the launch process has a greater impact on the launched equipment, and the equipment vibration reduction requirements during the launch process are extremely high. A material that can reduce the weight of the equipment and reduce its own vibration is currently urgently needed in the aerospace industry.

[0003] The scientific experiment cabinet is a test cabinet set up in the space station, in which a series of scientific experiments can be carried out. There are a large number of such cabinets in the space station. The reduction of their own weight and the ability to use vibration-damping materials will undoubtedly play a huge role in the construction of the space station. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method for forming a skin of a structurally integrated test cabinet, which solves the problem of heavy weight of previous metal cabinets and ensures that the skin has both load-bearing structural strength and can also play a vibration reduction role.

[0005] The object of the present invention is achieved by: a method for forming a skin of a structural and functional integrated test cabinet, comprising the following steps: Step 1) The main body skin is formed by laying with a negative mold, including an outer skin layer, a shock absorbing layer, and an inner skin layer. The outer skin layer and the inner skin layer are both made of carbon fiber prepreg, and the shock absorbing layer is made of damping prepreg. The skin is laid from the outside to the inside. After the laying is completed, it is put into an autoclave for high temperature and high pressure curing and molding. After demoulding, it is cut to obtain the main body skin; Step 2) The mouth cover plate is formed by flat die laying. Its structure is the same as that of the main body skin, including an outer skin layer, a shock absorbing layer, and an inner skin layer. The outer skin layer and the inner skin layer are both made of carbon fiber prepreg, and the shock absorbing layer is made of damping prepreg. The plates are laid from the outside to the inside. After the laying is completed, they are put into an autoclave for high temperature and high pressure curing and molding. After demolding, the mouth cover plate is obtained, and mounting holes are opened on the periphery of the mouth cover plate using processing equipment; Step 3) Make holes in the cabinet skin. Use the cover plate as a template to make holes in the main skin where holes are needed. Step 4) Install the mouth cover plate and install the mouth cover plate to the main body skin using fasteners.

[0006] Furthermore, the damping prepreg is composed of the following components: 45±2% of reinforced carbon fiber, 10±2% of epoxy resin, and 45±2% of damping prepreg.

[0007] Furthermore, the manufacturing process of the damping prepreg is as follows: 9 mm long T800 grade chopped carbon fiber is selected as the reinforcing carbon fiber, the chopped carbon fiber is added to the epoxy resin, stirred and diffused evenly, and then added to the damping prepreg and stirred evenly again, and finally a coating vulcanizer is used to make a damping prepreg with a thickness of 0.55±0.02 mm.

[0008] Furthermore, the specific process of forming the main body skin in step 1) includes: a) Design and manufacture a female mold of corresponding size and specifications, and use the female mold for production; b) Use a fully automatic cutting machine to cut prepreg and damping prepreg; c) The cabinet body skin is a pentahedral box structure with a uniform thickness of 1.5mm, including a 0.5mm outer skin, a 0.5mm damping prepreg and a 0.5mm inner skin. The outer skin and inner skin are made of T800 carbon fiber reinforced epoxy resin unidirectional prepreg and T800 carbon fiber reinforced epoxy resin plain prepreg. The single-layer thickness of the two prepregs is 0.125mm. Both the outer skin and the inner skin are 4-layer sheets. d) Adopt negative mold laying, first lay the outer skin, the thickness of the outer skin is 0.5mm, the outermost layer is 1 layer of T800 carbon fiber reinforced epoxy resin plain prepreg, and the remaining 3 layers are T800 carbon fiber reinforced epoxy resin unidirectional prepreg. The layer design angles are: 45°, 0°, 90°, 0°. After laying 4 layers of sheets, it is necessary to make vacuum pre-pumped bags to pre-compact the sheets; e) After the outer skin is laid, a layer of structural adhesive film is laid on the surface of the sheet, and after the laying is completed, a vacuum pre-evacuated bag is made for pre-compaction; f) Lay the damping prepreg on the surface of the pre-compacted structural adhesive film. The laying process should be slow. After the laying process is completed, make a vacuum pre-pumped bag for pre-compaction. g) After paving the damping prepreg, a layer of structural adhesive film is laid on its surface, and after paving, a vacuum pre-evacuated bag is made for pre-compaction; h) After the structural adhesive film is laid, the inner skin is laid. The inner skin is also 0.5mm. The inner skin is laid with 3 layers of T800 carbon fiber reinforced epoxy resin unidirectional prepreg and 1 layer of T800 carbon fiber reinforced epoxy resin plain prepreg. The ply design angles are 0°, 90°, 0°, and 45°. After the 4 layers of material are laid, a vacuum pre-pumped bag is made for pre-compaction; i) After all the sheets are laid, the final vacuum bag is made and put into the autoclave for high temperature and high pressure curing. The curing system is pressurized to 0.6Mpa, kept at 90℃ for 1 hour, and kept at 130℃ for 3 hours; j) After solidification and molding, the main body skin is separated from the female mold and the size allowance is cut to the net size using a cutting machine.

[0009] Furthermore, in step d) and step e), the adjacent cross-section pieces are laid in a staggered butt-jointed manner, and the pieces in the same layer are laid in a butt-jointed manner, with the butt joint gap ≤1mm, the butt joint gap between two adjacent layers of pieces must be controlled between 15-20mm, and the butt joints of every 4 layers of pieces cannot appear in the same position.

[0010] Furthermore, in step a), when designing the female mold, the expansion size of the mold material at the skin curing temperature is calculated through simulation software based on the linear expansion coefficient of the mold material, and the mold size at room temperature is obtained based on the dimensional change due to thermal expansion and contraction. Finally, the molding mold for the cabinet body skin is designed and processed based on this data. Similarly, the mold processing needs to be processed at a constant temperature of 25°C.

[0011] Furthermore, in step a) of preparing the negative mold, the mold paving surface needs to be subjected to foam grinding after CNC machining, and 80-mesh sand, 2000-mesh sand, oil stone and polishing cotton are used for grinding and polishing. During the polishing process, the roughness of the mold surface is continuously tested, and the paving surface accuracy needs to reach Rz≤0.4.

[0012] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention uses carbon fiber composite materials to make the cabinet skin, which greatly reduces the weight of the skin and reduces the energy consumption of space launch; (2) The present invention adopts a mixed laying method of carbon fiber prepreg and independently designed damping prepreg, which not only ensures the structural strength of the cabinet skin but also plays a vibration reduction role, reduces the use of dampers, reduces energy consumption during space launch, and optimizes the equipment placement space, so that the space for carrying cargo can be increased during a single launch; (3) The cabinet skin is made of composite materials, and its external dimensions are guaranteed by the mold. The cabinet skins produced in batches using a single set of molds are completely consistent in size and can be interchanged, effectively ensuring the spatial layout and installation accuracy within the space station, while reducing the difficulty of maintenance for astronauts. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0014] Figure 1 It is a flow chart of the present invention.

[0015] Figure 2 This is a schematic diagram of the integrated test cabinet skin structure made by the present invention.

[0016] Figure 3 This is an exploded view of the integrated test cabinet skin made by the present invention.

[0017] Figure 4 This is a cross-sectional view of the integrated test cabinet skin made by the present invention.

[0018] Among them, 101 is the outer skin layer, 102 is the shock-absorbing layer, 103 is the inner skin layer, 104 is the structural adhesive film, 200 is the composite skin, 300 is the skin side cover, 400 is the skin top cover, and 401 is the cross-shaped rib plate. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] like Figure 2-4 As shown, the present invention needs to design a structural and functional integrated test cabinet skin, including: The main body skin 200 is in the shape of a box, with an open bottom, side openings on both sides, and a top opening on the top; The skin side cover 300 is in the shape of a flat plate and is installed on the side opening of the main body skin 200; The skin top cover 400 is in the shape of a flat plate and is installed on the top opening of the main body skin 200 .

[0021] The main skin 200, the skin side cover 300 and the skin top cover 400 have the same structure, including an outer skin layer 101, a shock absorbing layer 102 and an inner skin layer 103. The outer skin layer 101 and the inner skin layer 103 are both made of carbon fiber reinforced epoxy resin prepreg, the shock absorbing layer 102 is made of damping prepreg, and a cross-shaped rib plate 401 is provided on the top of the skin top cover 400.

[0022] Example 1 like Figure 1 As shown, a method for forming a structural and functional integrated test body skin 200 includes the following steps: Step 1) forming the main body skin 200; The cabinet body skin 200 is the largest composite part, with dimensions of 1809mm×1043mm×780mm and a thickness of 1.5mm. To ensure its external dimensions, a steel female mold is used for laying. Its final dimensions and equipment installation port dimensions are ensured by cutting. The specific molding process is as follows: a) Aviation equipment generally requires that the product surface must be smooth and without sharp edges. Once a person in space is scratched by a sharp object, it is difficult to stop the bleeding. Therefore, the mold surface of the cabinet body skin 200 must be smooth and free of defects. It is made using a negative mold and a steel negative mold is prepared.

[0023] b) Aerospace equipment has extremely strict weight control. We use accurate software to make detailed drawings, and use fully automatic cutting machines to cut prepreg and damping prepreg.

[0024] c) The cabinet body skin 200 is a 5-sided boxed structure with a uniform thickness of 1.5mm, which includes a 0.5mm outer skin, a 0.5mm damping prepreg and a 0.5mm inner skin. The prepregs used are T800-grade carbon fiber reinforced epoxy resin unidirectional prepreg and T800-grade carbon fiber reinforced epoxy resin plain prepreg. The single-layer thickness of the two prepregs is 0.125mm. The outer skin and the inner skin are both 4-layer sheets.

[0025] d) Use negative mold paving, first lay out the outer skin. According to the design, the outermost layer is a layer of T800 carbon fiber reinforced epoxy resin plain prepreg, and the remaining 3 layers are T800 carbon fiber reinforced epoxy resin unidirectional prepreg. The ply design angles are (45°, 0°, 90°, 0°). To ensure that there are no bubbles, gaps, or wrinkles between the prepreg layers, a vacuum pre-vacuum bag needs to be made to pre-compact the prepreg after paving the 4 layers.

[0026] e) After the outer skin is laid, a layer of J-165 structural adhesive film 104 is laid on the surface of the sheet to ensure the bonding strength between the damping prepreg and the prepreg. After the laying is completed, a vacuum pre-evacuated bag is made for pre-compaction.

[0027] f) The damping prepreg is laid on the surface of the pre-compacted structural adhesive film 104. The damping prepreg is soft and needs to be laid slowly to ensure quality. After laying, a vacuum pre-pumped bag is made for pre-compaction. The damping prepreg consists of the following components: 45±2% reinforced carbon fiber, 10±2% epoxy resin, and 45±2% damping prepreg. The optimal choice is 45% reinforced carbon fiber, 10% epoxy resin, and 45% damping prepreg. The manufacturing process of the damping prepreg is as follows: 9mm long T800 grade chopped carbon fiber is selected as the reinforced carbon fiber, the chopped carbon fiber is added to the epoxy resin, stirred and diffused evenly, and then added to the damping prepreg and stirred evenly again, and finally a film coating vulcanizer is used to make a damping prepreg with a thickness of 0.55±0.02mm.

[0028] g) After paving the damping prepreg, a layer of J-165 structural adhesive film 104 is laid on the surface. After paving, a vacuum pre-vacuum bag is made for pre-compaction.

[0029] h) After the structural adhesive film 104 is laid, the inner skin is laid. The thickness of the inner skin is also 0.5mm. The inner skin is laid with 3 layers of unidirectional prepreg and 1 layer of plain prepreg. The designed laying angles are (0°, 90°, 0°, 45°). After the 4 layers of material are laid, a vacuum pre-bag is made for pre-compaction.

[0030] i) After all the sheets are laid, the final vacuum bag is made and put into the autoclave for high temperature and high pressure curing. The curing system is pressurized to 0.6Mpa, kept at 90℃ for 1 hour, and kept at 130℃ for 3 hours.

[0031] j) After solidification and molding, the cabinet body skin 200 is separated from the female mold and the size margin is cut to the net size using a cutting machine.

[0032] Step 2) Forming and manufacturing of the cover plates (including the skin side covers 300 and the skin top cover 400).

[0033] The equipment installation port cover plates mainly include two specifications, with the dimensions of the back equipment installation port cover plate being 960mm×880m×1.5mm, and the side equipment installation port cover plate being 650mm×340mm×1.5mm. The thickness of both cover plates is 1.5mm, and their layer design is consistent with the main skin 200, which is also 0.5mm outer skin + 0.5mm damping prepreg + 0.5mm inner skin.

[0034] The equipment installation port cover is a flat structure, which can be formed by paving with a steel flat mold. It also has 4 layers of outer skin, 4 layers of inner skin, and a layer of damping prepreg in the middle. A layer of J-165 structural adhesive film 104 needs to be laid between the damping prepreg and the carbon fiber prepreg to increase the bonding performance. When laying the sheet, a vacuum pre-evacuated bag needs to be made for every 4 layers to pre-compact the sheet. After the structural adhesive film 104 and the damping prepreg are laid, they need to be pre-compacted separately. The layer design angle is (45°, 0°, 90°, 0°, adhesive film, damping, adhesive film, 0°, 90°, 0°, 45°). After all the sheets are laid, the final vacuum bag is made and put into the autoclave for high temperature and high pressure curing. Its curing system is consistent with the cabinet main body skin 200.

[0035] After the cover plate is solidified and formed, in order to ensure its external dimensions and the drilling accuracy of the bolt holes, the CNC machining center is used to perform trimming and drilling at the same time.

[0036] Step 3) Install the 200 holes on the main skin After all the composite parts are manufactured, the processed equipment installation cover is used as a transfer template to open holes at the locations where bolt holes need to be opened on the cabinet body skin 200, so that the holes can be seamlessly installed with the equipment installation cover.

[0037] It should be noted that the damping prepreg is a composite material of damping prepreg + epoxy resin + reinforcing fiber. Since the main body skin 200 is used in the space station, the weight requirement is extremely strict. If ordinary damping rubber is used, according to the simulation calculation, the overall thickness of the main body skin 200 must be more than 2mm, in order to ensure that the main body skin 200 is controlled at 1.5mm thickness while being able to meet the structural strength requirements. The damping prepreg used in the present invention has the functions of damping and structural strength at the same time. According to a large number of calculations, experiments, and tests, 9mm long T800 grade short-cut carbon fibers are finally selected as reinforcing materials, and the carbon fiber content is controlled at 45%, the epoxy resin content is 10%, and the damping prepreg content is 45%. The short-cut carbon fibers are added to the epoxy resin, stirred and diffused evenly, and then added to the damping prepreg and stirred evenly again. Finally, a coating vulcanizer is used to make a damping prepreg with a thickness of 0.55±0.02mm. (Since the damping prepreg has a certain elasticity, its thickness will be compressed after being made into the main skin 200 and subjected to high temperature and high pressure treatment in an autoclave. According to a large number of tests, the thickness of the raw material needs to be made to 0.55mm, and the thickness after curing is just about 0.5mm).

[0038] It should be noted that the cabinet body skin 200 and the equipment installation port cover are both made of T800-grade carbon fiber reinforced epoxy resin prepreg and self-designed damping prepreg to achieve both weight reduction and vibration reduction functions. This makes the structural damping ratio G of the main body skin 200 and the equipment installation port cover ≤ 0.3, and the power amplification factor ≤ 3.5.

[0039] Considering the health of aerospace test personnel in the space station, the total mass loss of volatile matter in the composite materials used is required to be TML (total mass loss) ≤1%, and CVCM (collected condensable volatiles) ≤0.1%.

[0040] The following is the list of main parts and materials of the main skin 200: Serial number Parts Name Material composition 1 Cabinet body skin 200 T800 carbon fiber reinforced epoxy resin plain prepreg + T800 carbon fiber reinforced epoxy resin unidirectional prepreg + damping prepreg + J165 damping special structural adhesive film 2 Rear equipment installation cover T800 carbon fiber reinforced epoxy resin plain prepreg + T800 carbon fiber reinforced epoxy resin unidirectional prepreg + damping prepreg + J165 damping special structural adhesive film 3 Side equipment port installation cover T800 carbon fiber reinforced epoxy resin plain prepreg + T800 carbon fiber reinforced epoxy resin unidirectional prepreg + damping prepreg + J165 damping special structural adhesive film It should be noted that in order to ensure the interlaminar strength between the damping prepregs, a special J-165 epoxy structural adhesive film is used between the carbon fiber prepreg and the damping prepreg, and its bonding strength after curing is consistent with the interlaminar strength of the prepreg.

[0041] It should be noted that, since the cabinet body skin 200 is a 5-sided box structure, the overall paving of prepreg means that there is a cross interface of the sheet between every two adjacent faces. In order to ensure that the rear thickness of the cabinet body skin 200 remains unchanged at 1.5mm, the sheets of adjacent cross sections are paved by staggered docking. In order to ensure the structural strength of the skin butt joint, the butt joint gap between two adjacent layers of sheets must be controlled between 15-20mm, and the butt joints of every four layers of sheets cannot appear in the same position.

[0042] Specifically, the mouth cover plate and the main body skin 200 are installed and connected with bolts. The mouth cover plate is trimmed and drilled by a CNC machining center. The mouth cover plate is placed on the surface of the main body skin 200 with holes and directly connected with bolts to complete the installation. In order to ensure that the bolts will not loosen due to vibration during launch, high-locking bolts are used.

[0043] It should be noted that the main body skin 200 has strict requirements on weight in terms of size, surface accuracy, skin thickness, etc. The main body skin 200 is a box-shaped pentahedron structure, and its external dimensions and surface accuracy are mainly guaranteed by the mold, so the precision of the paving molding mold of the cabinet main body skin 200 is required to be high.

[0044] According to the design requirements, the length, width, height and other dimensional tolerances of the main body skin 200 are required to be ≤1mm, and the surface accuracy tolerance is within ±0.2mm. To achieve this requirement, in the early stage of mold design, it is necessary to calculate its expansion size at the skin curing temperature through simulation software based on the linear expansion coefficient of the mold material, and calculate the mold size at room temperature (25°C) based on its dimensional changes due to thermal expansion and contraction. Finally, the molding mold of the cabinet main body skin 200 is designed and processed based on this data. Similarly, the mold processing needs to be processed under a constant temperature of 25°C.

[0045] Considering the total mass loss requirements of the volatile matter of the raw materials used in the main skin 200, TML (total mass loss) ≤ 1%, CVCM (collected condensable volatiles) ≤ 0.1%, its outer surface cannot be painted. According to the design requirements, the surface of the main skin 200 directly uses a carbon fiber surface, while ensuring the smoothest effect, and its surface roughness Rz ≤ 0.4. Since the surface roughness of all composite parts of the main skin 200 is guaranteed by the mold, the mold paving surface accuracy needs to reach Rz ≤ 0.4. According to the smoothest processing requirements, the mold paving surface needs to be foamed after CNC machining. 80 mesh sand, 2000 mesh sand, oil stone and polishing cotton are used for polishing and polishing. The roughness of the mold surface is continuously tested during the polishing process.

[0046] In order to ensure that the thickness tolerance of the main skin 200 composite parts after curing and forming meets the requirements, the joint requirements of the paving sheets are extremely strict. The T800 carbon fiber prepreg inner skin has 4 layers and the outer skin has 4 layers. The sheets in the same layer are paved by butt joint, and the butt joint gap is ≤1mm. The adjacent two layers of sheets are paved by staggered butt joint. In order to ensure the structural strength of the skin butt joint, the butt joint gap between the adjacent two layers of sheets must be controlled between 15-20mm, and the butt joints of every 4 layers of sheets cannot appear in the same position. Since the damping prepreg has a certain elasticity, its thickness will be appropriately thinned and its size will be appropriately enlarged after curing and forming. If the conventional sheet butt joint method is used for paving, wrinkles are easily formed after curing. After a large number of tests, it is found that a gap of 3-4mm needs to be reserved at the butt joint of the damping prepreg sheets, so that the surface of the composite material after curing is smooth and wrinkle-free and the thickness can be guaranteed to be around 1.5mm.

[0047] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for forming a skin of a structural and functional integrated test cabinet, characterized in that: The following steps are involved: Step 1) forming a main body skin (200) by laying out using a negative mold, including an outer skin layer (101), a shock absorbing layer (102), and an inner skin layer (103), wherein the outer skin layer (101) and the inner skin layer (103) are both made of carbon fiber prepreg, and the shock absorbing layer (102) is made of damping prepreg, and laying is performed from the outside to the inside. After the laying is completed, it is put into an autoclave for high temperature and high pressure curing and molding, and after demoulding, it is cut to obtain the main body skin (200); Step 2) The mouth cover plate is formed by flat die laying. Its structure is the same as that of the main body skin (200), including an outer skin layer (101), a shock absorbing layer (102), and an inner skin layer (103). The outer skin layer (101) and the inner skin layer (103) are both made of carbon fiber prepreg, and the shock absorbing layer (102) is made of damping prepreg. The plates are laid from the outside to the inside. After the laying is completed, they are put into an autoclave for high temperature and high pressure curing and molding. After demoulding, the mouth cover plate is obtained. The mounting holes are opened on the outer periphery of the mouth cover plate using processing equipment; Step 3) The cabinet skin is provided with holes, and holes are drilled at the locations where holes are required on the main body skin (200) using the cover plate as a template; Step 4) Install the mouth cover plate: install the mouth cover plate onto the main body skin (200) using fasteners.

2. The method for forming the skin of a structural and functional integrated test cabinet according to claim 1, characterized in that: The damping prepreg is composed of the following components: 45±2% of reinforced carbon fiber, 10±2% of epoxy resin and 45±2% of damping prepreg.

3. The method for forming the skin of a structural and functional integrated test cabinet according to claim 2, characterized in that: The manufacturing process of the damping prepreg is as follows: 9 mm long T800 grade chopped carbon fiber is selected as reinforcing carbon fiber, the chopped carbon fiber is added into epoxy resin, stirred and diffused evenly, then added into the damping prepreg and stirred evenly again, and finally a coating vulcanizer is used to make the damping prepreg with a thickness of 0.55±0.02 mm.

4. A method for forming a skin of a structural and functional integrated test cabinet according to any one of claim 3, characterized in that: The specific process of forming the main body skin (200) in step 1) includes: a) Design and manufacture a female mold of corresponding size and specifications, and use the female mold for production; b) Use a fully automatic cutting machine to cut prepreg and damping prepreg; c) The cabinet body skin (200) is a pentahedral box structure with a uniform thickness of 1.5 mm, including a 0.5 mm outer skin, a 0.5 mm damping prepreg and a 0.5 mm inner skin. The outer skin and the inner skin are made of T800 grade carbon fiber reinforced epoxy resin unidirectional prepreg and T800 grade carbon fiber reinforced epoxy resin plain prepreg. The single layer thickness of the two prepregs is 0.125 mm. The outer skin and the inner skin are both 4-layer sheets; d) Adopt negative mold laying, first lay the outer skin, the thickness of the outer skin is 0.5mm, the outermost layer is 1 layer of T800 carbon fiber reinforced epoxy resin plain prepreg, and the remaining 3 layers are T800 carbon fiber reinforced epoxy resin unidirectional prepreg. The layer design angles are: 45°, 0°, 90°, 0°. After laying 4 layers of sheets, it is necessary to make vacuum pre-pumped bags to pre-compact the sheets; e) After the outer skin is laid, a layer of structural adhesive film (104) is laid on the surface of the sheet, and after the laying is completed, a vacuum pre-evacuated bag is made for pre-compaction; f) laying the damping prepreg on the surface of the pre-compacted structural adhesive film (104), laying the material slowly, and after the laying is completed, making a vacuum pre-evacuated bag for pre-compaction; g) After the damping prepreg is laid, a layer of structural adhesive film (104) is laid on the surface thereof, and after the laying is completed, a vacuum pre-evacuated bag is made for pre-compaction; h) After the structural adhesive film (104) is laid, the inner skin is laid. The inner skin is also 0.5 mm thick. The inner skin is laid with 3 layers of T800 carbon fiber reinforced epoxy resin unidirectional prepreg and 1 layer of T800 carbon fiber reinforced epoxy resin plain prepreg. The layer design angles are 0°, 90°, 0°, and 45°. After the 4 layers of material are laid, a vacuum pre-pumped bag is made for pre-compaction; i) After all the sheets are laid, the final vacuum bag is made and put into the autoclave for high temperature and high pressure curing. The curing system is pressurized to 0.6Mpa, kept at 90℃ for 1 hour, and kept at 130℃ for 3 hours; j) After solidification and molding, the main body skin (200) is separated from the female mold and cut to the net size by a cutting machine.

5. A method for forming a skin of a structural and functional integrated test cabinet according to claim 4, characterized in that: In step d) and step e), the adjacent cross-section pieces are laid in a staggered manner, and the pieces in the same layer are laid in a butt-jointed manner, with the butt joint gap ≤1mm. The butt joint gap between two adjacent layers of pieces must be controlled between 15-20mm, and the butt joints of every 4 layers of pieces cannot appear in the same position.

6. A method for forming a skin of a structural and functional integrated test cabinet according to claim 4, characterized in that: Step a) When designing the female mold, the expansion size of the mold material at the skin curing temperature is calculated using simulation software based on the linear expansion coefficient of the mold material, and the mold size at room temperature is obtained based on the size change due to thermal expansion and contraction. Finally, the molding mold of the cabinet body skin (200) is designed and processed based on this data. Similarly, the mold processing needs to be processed at a constant temperature of 25°C.

7. A method for forming a skin of a structural and functional integrated test cabinet according to claim 4, characterized in that: Step a) When preparing the negative mold, the mold paving surface needs to be foam polished after CNC machining. 80 mesh sand, 2000 mesh sand, oil stone and polishing cotton are used for polishing. The roughness of the mold surface is continuously tested during the polishing process. The paving surface accuracy needs to reach Rz≤0.4.

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