A method for shaping needle punched carbon / carbon-copper composite felt

Abstract

The present application relates to a kind of needle punching carbon / carbon-copper composite felt body shaping method, belong to the field of materials for electric locomotive.The present application is based on industrialized production process, it is found that carbon fiber-copper felt body with copper mesh of large size weaving is prone to uncontrollable deformation in subsequent processing process, first proposes to obtain the product with excellent shaping by using special pre-impregnation-curing process and recarbonization.In the process of exploration, it is found that when the preform is placed into the box, the woven felt is flat, the offset angle of the woven carbon fiber and copper wire in the product is small, and the offset quantity is also small.The present application is simple and controllable, and is easy to be industrialized.

Description

Technical Field

[0001] This invention relates to a shaping method for needled carbon / carbon-copper composite felt, belonging to the field of materials for electric locomotives. Background Technology

[0002] The slider is bonded to an aluminum alloy to form a carbon sliding plate. By sliding against the high-voltage contact wire, electricity is transmitted from the contact network to the locomotive, fulfilling the function of current conduction. As electric locomotives develop towards higher speeds, the slider experiences increasing impact from the contact network during sliding. Therefore, an excellent slider must possess both low resistivity and good impact resistance.

[0003] Carbon / carbon-copper composite materials utilize carbon fiber as reinforcement, exhibiting significantly improved impact toughness compared to existing metal-impregnated carbon materials. They are less prone to edge chipping and spalling, and possess superior wear resistance, making them an internationally recognized next-generation carbon slide material. Current manufacturing processes for carbon / carbon-copper composite materials involve first weaving carbon fibers and copper mesh into a preform of a certain density, followed by densification through chemical vapor deposition and resin impregnation-carbonization to ultimately form the carbon / carbon-copper composite. A problem with this process is that the woven felt is relatively soft, and the inclusion of continuous copper mesh makes it prone to deformation during subsequent impregnation and / or vapor deposition, leading to difficulty in controlling product precision. Therefore, current technologies typically use chemical vapor deposition for shaping, which is costly and requires extensive graphite tooling, resulting in low furnace space utilization. Therefore, a shaping method for woven carbon fiber and copper mesh preforms needs to be developed to improve equipment space utilization and reduce production costs. Summary of the Invention

[0004] This invention addresses the problem discovered during industrial production: large-sized carbon fiber-copper felt bodies woven with copper mesh are prone to uncontrollable deformation during subsequent processing. It proposes for the first time a special pre-impregnation-curing process combined with subsequent carbonization to achieve a product with excellent shape retention. During the exploration process, it was found that when the pre-fabricated felt body is flat before being placed in the box, using the process of this invention results in a smaller offset angle and a smaller amount of offset between the woven carbon fibers and copper wires in the product.

[0005] The technical problem to be solved by this invention is to propose a simple and low-cost manufacturing method for the shaping of woven carbon fiber and copper mesh preforms.

[0006] This invention modifies the process, employing a special impregnation process after weaving a pre-fabricated felt containing copper mesh, to shape it and introduce a thermally decomposed carbon source. The specific operations are as follows:

[0007] This invention discloses a method for shaping a needle-punched carbon / carbon-copper composite felt, comprising the following steps:

[0008] Step 1

[0009] Carbon fiber nonwoven fabric and carbon fiber mesh are sequentially stacked in the following order: 0° nonwoven carbon fabric, copper mesh, mesh, 90° nonwoven carbon fabric, copper mesh, mesh, and 0° nonwoven carbon fabric. Carbon fiber bundles are introduced into the layup direction perpendicular to the layup direction using a relay needle punching method to produce a needle punched prefabricated felt containing copper mesh.

[0010] Step Two

[0011] A needle-punched prefabricated felt containing copper mesh is placed in a box C with openings on all four sides and the bottom, for later use. The top cover of box C can move up and down along the height of the box, and the area of ​​the top cover is greater than 2 / 3 of the area of ​​the bottom of the box. The top cover also has through holes. Preferably, the holes on the top cover of box C are conical holes, with the smaller hole facing outwards and the larger hole facing inwards. The diameter of the larger hole is A, which is 0.5~1.5cm, and the diameter of the smaller hole is 0.5~0.75A. The distance from the edge of any large hole inside to the adjacent large hole is less than 0.3cm.

[0012] The holes on the bottom and side walls of box C are conical holes, with the smaller hole facing inward and the larger hole facing outward; the diameter of the larger hole is A, and A ranges from 0.5 to 1.5 cm; the diameter of the smaller hole is 0.5 to 0.75A; the distance from the edge of any large hole inside to the adjacent large hole is less than 0.3 cm;

[0013] Step 3

[0014] Add a curing agent to liquid furan resin and preheat it fully at 50~70℃; immerse box C containing the needled preformed felt with copper mesh in the furan resin solution, pull it along the height of the box and press the top cover back at least 3 times; and during the pressing back operation, at least once the top cover comes into contact with the needled preform containing copper mesh (mere contact should not apply external pressure to the preform); then remove the box containing the needled preform with copper mesh and let it stand until no resin flows out;

[0015] Step Four

[0016] Place the stainless steel box from step three into an oven at 160~200℃ and remove it after 90~150 minutes to allow the resin to cure; thus obtaining a pre-made felt containing resin and copper mesh.

[0017] Step 5

[0018] The pre-made felt containing resin and copper mesh obtained in step four is placed in box C with openings on all four sides and bottom. Steps three and four are repeated to obtain a pre-made felt containing resin and copper mesh that has been impregnated and cured twice.

[0019] Step Six

[0020] The pre-made felt containing resin and copper mesh obtained from step five, which has undergone secondary impregnation and curing, is placed in a carbonization furnace and heated to above 800°C for carbonization treatment, thus obtaining a shaped needle-punched carbon / carbon-copper felt body.

[0021] Preferably, the box is made of stainless steel.

[0022] Preferably, the holes on the top cover of the box are conical holes, with the smaller hole facing outwards and the larger hole facing inwards; the diameter of the larger hole is A, which ranges from 0.9 to 1.2 cm, and the diameter of the smaller hole is 0.5 to 0.55A. The distance from the edge of any one of the larger holes to the adjacent larger hole is less than 0.3 cm.

[0023] Preferably, the holes at the bottom of the box are tapered, with the smaller hole facing inward and the larger hole facing outward; the diameter of the larger hole is A, which ranges from 0.9 to 1.2 cm, and the diameter of the smaller hole is 0.5 to 0.55A. The distance from the edge of any one of the larger holes to the adjacent larger hole is less than 0.3 cm.

[0024] The contact area between the downward or upward pressure rod connected to the top cover of box C and the top cover of box C is greater than or equal to 0.3 times the area of ​​the top cover of box C and less than the area of ​​the top cover of box C.

[0025] Preferably, the shape of the box bottom and the shape of the precast felt bottom are mathematically similar; and the area of ​​the box bottom is 1.01 to 1.2 times the area of ​​the precast felt bottom. The shape of the box top and the shape of the precast felt bottom are mathematically similar; and the area of ​​the box top is 0.99 to 1.005 times the area of ​​the precast felt bottom. In this invention, the use of conical holes, especially with the top cover having small holes facing outwards and large holes facing inwards, and the bottom having small holes facing inwards and large holes facing outwards, combined with appropriate hole diameters, ensures that the resin enters the box evenly during impregnation, uniformly impregnating the precast felt. Furthermore, it ensures that the pressure on the lower surface of the product is slightly greater than that on the upper surface during impregnation, thus reducing the probability of product deformation. This process allows for the incorporation of as many continuous copper meshes as possible during weaving.

[0026] The length, width, and height of the needle-punched preform containing copper mesh are (1000-1200) mm × (300-400) mm × (40-45) mm. The volume percentage of copper in the needle-punched preform containing copper mesh is 1-30%. The curing agent is selected from at least one of phosphoric acid, sulfuric acid, and nitric acid, preferably phosphoric acid.

[0027] The mass ratio of liquid furan resin to curing agent is 1-100:10-150.

[0028] Preferably, the present invention involves adding a curing agent to liquid furan resin and preheating it thoroughly at 50-70°C; immersing a box containing a needle-punched pre-fabricated felt with copper mesh in the furan resin solution, pulling along the height of the box and pressing back the top cover 3-5 times; and ensuring that the top cover contacts the needle-punched pre-fabricated felt containing copper mesh at least once during the pressing back operation; then removing the box containing the needle-punched pre-fabricated felt with copper mesh and allowing it to stand until no resin flows out. This operation further ensures the uniform distribution of furan resin and curing agent within the felt, and also minimizes deformation caused by the copper mesh.

[0029] As a further preferred embodiment, the present invention adds a curing agent to liquid furan resin and preheats it fully at 50~70°C; after immersing the box containing the needle-punched pre-fabricated felt with copper mesh in the furan resin solution for at least 3 minutes, the top cover is pulled along the height of the box and the immersion continues for 1-2 minutes, the top cover is then pressed back, and the immersion continues for 1-2 minutes. The operation of pulling and pressing the top cover is repeated 2-4 times. The box containing the needle-punched pre-fabricated felt with copper mesh is then removed and left to stand until no resin flows out.

[0030] Preferably, after the impregnation in step three is completed, the box containing the needle-punched pre-fabricated felt containing the copper mesh is removed, and the top surface is placed down until no resin flows out. This operation can further reduce the deformation of the felt.

[0031] In step four of this invention, the oven is first heated to 160-200°C, and then the box containing the needled preform with copper mesh from step three is placed in it and dried to obtain a preformed felt containing resin and copper mesh.

[0032] Preferably, in step five, the prefabricated felt containing resin and copper mesh obtained in step four is placed in box C with openings on all four sides and bottom, with the bottom surface of the prefabricated felt in step three as the top surface of step five and the top surface of the prefabricated felt in step three as the bottom surface of step five. Steps three and four are repeated to obtain a prefabricated felt containing resin and copper mesh that has been impregnated and cured twice.

[0033] The shaped felt obtained by this invention does not require tooling and can be directly placed into a chemical vapor deposition furnace for densification.

[0034] Principles and advantages

[0035] Needle-punched precast felt contains more than 70% pores, which are interconnected. When the content of woven copper mesh is large, it is very easy to induce deformation of the felt body during subsequent construction (including impregnation or vapor deposition). This invention addresses this by using conical holes on the top cover of box C, with the smaller hole facing outwards and the larger hole facing inwards; the diameter of the larger hole is A, which is 0.5~1.5cm, and the diameter of the smaller hole is 0.5~0.75A. The distance from the edge of any large hole to the adjacent large hole is less than 0.3cm. The holes on the bottom and side walls of box C are conical holes, with the smaller hole facing inwards and the larger hole facing outwards. The holes face outwards; the diameter of the large hole is A, which ranges from 0.5 to 1.5 cm, and the diameter of the small hole is 0.5 to 0.75A. The design ensures that the distance from the edge of any large hole to an adjacent large hole is less than 0.3 cm. This minimizes deformation of the felt, especially large-area felt. Combined with the subsequent operation of "pulling and pressing the top cover along the height of box C at least three times; and during the pressing operation, at least one contact with the needle-punched preform containing copper mesh without generating mechanical pressure," the resin and curing agent are redistributed, increasing the probability of uniform distribution. Finally, curing is performed in an inverted manner, further reducing the possibility of product deformation or uneven deformation due to the high density of copper. After the first curing, the inverted method, combined with box C and a special impregnation method, further reduces the probability of deformation. Attached Figure Description

[0036] Figure 1 This is a photograph of the product obtained in Example 1.

[0037] Figure 2 The image shows the product obtained in Example 1 after being polished on the surface formed by the length and width until the copper wire mesh is visible.

[0038] Figure 3 This is a photograph of the product obtained in Example 2.

[0039] Figure 4 This is a photograph of the product obtained in Comparative Example 1.

[0040] Figure 5 This is a photograph of the product obtained in Comparative Example 2.

[0041] Figure 6 This is a photograph of the product obtained in Comparative Example 3.

[0042] Figure 7 This is a schematic diagram of the stainless steel box used in the embodiment;

[0043] Figure 8 This is a cross-sectional view of the stainless steel box used in the embodiment. Detailed Implementation

[0044] Example 1:

[0045] The carbon / carbon-copper composite material slider in this embodiment is mainly prepared through the following steps:

[0046] (1) First, non-woven fabric and mesh were made using PAN-type T700 (12K) carbon fiber manufactured by Toray Industries, Ltd. of Japan. The non-woven fabric was layered in a cyclical pattern: 0° non-woven fabric, copper mesh, mesh, 90° non-woven fabric, copper mesh, mesh, and 0° non-woven fabric. Carbon fiber and copper wire were introduced perpendicular to the layup direction using a relay-type needle punching method, and the sample was woven to a density of 1.53 g / cm³. 3 The prefabricated felt body. The volume content of the copper mesh is 18% of the prefabricated felt body; the prefabricated felt body is a cuboid with a length, width and height of 1200mm × 400mm × 42mm;

[0047] (2) Place the above prefabricated body into a stainless steel box with openings on all four sides and the bottom (the structure of the stainless steel box is as follows). Figure 7 , 8 As shown, the stainless steel box is for use only. The top cover of the stainless steel box has conical holes, with the smaller hole facing outwards and the larger hole facing inwards; the diameter of the larger hole is A, where A is 1cm, and the diameter of the smaller hole is 0.5A. The distance from the edge of any large hole inside to an adjacent large hole is 0.15cm. The bottom of the stainless steel box also has conical holes, with the smaller hole facing inwards and the larger hole facing outwards; the diameter of the larger hole is A, where A is 1cm, and the diameter of the smaller hole is 0.5A. The distance from the edge of any large hole inside to an adjacent large hole is 0.18cm. The side walls of the box also have through holes with a diameter of 1cm. The shape of the bottom of the box is mathematically similar to the shape of the bottom surface of the precast felt; and the area of ​​the bottom of the box is 1.1 times the area of ​​the bottom of the precast felt. The shape of the top cover of the box is mathematically similar to the shape of the bottom surface of the precast felt; and the area of ​​the top cover of the box is 1.0 times the area of ​​the bottom of the precast felt. (3) Add a curing agent (the curing agent is phosphoric acid) to the liquid furan resin and preheat it fully at 60°C. Immerse the stainless steel box containing the preform in the furan resin solution. Immerse the box containing the needle-punched preform containing the copper mesh in the furan resin solution for 4 minutes. Then pull the top cover upward along the height of the box (when the top cover is pulled upward, the top cover and the needle-punched preform are in contact and have a weak interaction force). Continue to immerse for 2 minutes. Then press the top cover back (press the top cover back until the needle-punched preform containing the copper mesh is in contact but without generating mechanical pressure). After pressing back, immerse for another 2 minutes. Repeat the operation of pulling the top cover and pressing back the top cover twice. Take out the box containing the needle-punched preform containing the copper mesh and place it with the top cover facing down (i.e., upside down) until no resin flows out.

[0048] (4) Place the stainless steel box in an oven at 180°C. After 2 hours, the resin will be cured and the box will be removed to obtain a pre-made felt containing resin and copper mesh.

[0049] (5) Place the prefabricated felt containing resin and copper mesh obtained in step (4) into box C with openings on all sides and bottom, and repeat steps three and four (1 time) to obtain a prefabricated felt containing resin and copper mesh that has been impregnated and cured twice.

[0050] (6) The pre-made felt containing resin and copper mesh, which has been impregnated and cured twice in step (5), is placed in a carbonization furnace and heated to 850°C for carbonization treatment. This yields a well-shaped needle-punched carbon / carbon-copper felt body with a measured density of 1.59 g / cm³. 3 After cost calculation, the cost of each additional kilogram of charcoal is 78 yuan. The resulting product is a cuboid. (Example: ...) Figure 1 As shown, over 95% of the carbon fibers and copper wires introduced perpendicular to the layup direction remain perpendicular. This 95% figure is statistical; the remaining offset carbon fibers and copper wires have a maximum offset angle of less than 37°. Figure 2 The product obtained in Example 1 was polished with carbonaceous material until the actual copper wire mesh was visible.

[0051] Example 2:

[0052] The carbon / carbon-copper composite material slider in this embodiment is mainly prepared through the following steps:

[0053] (1) First, non-woven fabric and mesh were made using PAN-type T700 (12K) carbon fiber manufactured by Toray Industries, Japan. The non-woven fabric was layered in a cyclical pattern: 0° non-woven fabric, copper mesh, mesh, 90° non-woven fabric, copper mesh, mesh, and 0° non-woven fabric. Carbon fiber and copper wire were introduced perpendicular to the layup direction using a relay-type needle punching method, and the sample was woven to a density of 1.18 g / cm³. 3 The prefabricated felt body. The volume content of the copper mesh is 10% of the prefabricated felt body; the prefabricated felt body is a cuboid with dimensions of 1200 mm × 400 mm × 42 mm (length, width, and height).

[0054] (2) Place the prefabricated body into a stainless steel box with openings on all four sides and the bottom, for later use. The top cover of the stainless steel box has a conical hole, with the smaller hole facing outwards and the larger hole facing inwards; the diameter of the larger hole is A, where A is 1.5cm, and the diameter of the smaller hole is 1cm. The distance from the edge of any large hole inside to the adjacent large hole is 0.3cm. The holes at the bottom of the stainless steel box are also conical holes, with the smaller hole facing inwards and the larger hole facing outwards; the diameter of the larger hole is A, where A is 1.5cm, and the diameter of the smaller hole is 1cm. The distance from the edge of any large hole inside to the adjacent large hole is 0.3cm. The side wall of the box also has through holes with a diameter of 1.5cm. The shape of the bottom of the box and the shape of the bottom surface of the precast felt are mathematically similar; and the area of ​​the bottom of the box is 1.1 times the area of ​​the bottom of the precast felt; the shape of the top cover of the box and the shape of the bottom surface of the precast felt are mathematically similar; and the area of ​​the top cover of the box is 1.0 times the area of ​​the bottom of the precast felt. (3) Add a curing agent (the curing agent is sulfuric acid) to the liquid furan resin and preheat it fully at 60°C. The stainless steel box containing the preform was immersed in a furan resin solution. The box containing the needled preform containing copper mesh was immersed in the furan resin solution for 4 minutes. Then, the top cover was pulled upward along the height of the box (when the top cover was first pulled upward, the top cover and the needled preform were in contact and had a slight interaction force). After immersion for 2 minutes, the top cover was pressed back (pressed back until the needled preform containing copper mesh was in contact but without generating mechanical pressure). After pressing back, it was immersed for another 2 minutes. The operation of pulling the top cover and pressing back the top cover was repeated twice. The box containing the needled preform containing copper mesh was then removed and placed with the top cover facing down (i.e., upside down) until no resin flowed out.

[0055] (4) Place the stainless steel box in an oven at 180°C. After 2 hours, the resin will be cured and the box will be removed to obtain a pre-made felt containing resin and copper mesh.

[0056] (5) Place the prefabricated felt containing resin and copper mesh obtained in step (4) into box C with openings on all sides and bottom, and repeat steps three and four (1 time) to obtain a prefabricated felt containing resin and copper mesh that has been impregnated and cured twice.

[0057] (6) The preform obtained in step (5) is placed in a carbonization furnace and heated to 850°C for carbonization treatment, thus obtaining a shaped needle-shaped carbon / carbon-copper felt body with a measured density of 1.21 g / cm³. 3 After cost calculation, the cost of each additional kilogram of charcoal is 81 yuan.

[0058] The resulting product is a cuboid. For example... Figure 3 As shown: over 90% of the carbon fibers and copper wires introduced perpendicular to the layup direction remain perpendicular. This 90% figure is statistical; the remaining offset carbon fibers and copper wires have a maximum offset angle of less than 45°.

[0059] Example 3

[0060] All other conditions are the same as in Example 1, except that:

[0061] (2) Place the prefabricated body into a stainless steel box with openings on all four sides and the bottom, for later use. The top cover of the stainless steel box has a conical hole, with the smaller hole facing outwards and the larger hole facing inwards; the diameter of the larger hole is A, which is 0.5cm, and the diameter of the smaller hole is 0.25cm. The distance from the edge of any large hole inside to the adjacent large hole is 0.25cm. The holes at the bottom of the stainless steel box are also conical holes, with the smaller hole facing inwards and the larger hole facing outwards; the diameter of the larger hole is A, which is 0.5cm, and the diameter of the smaller hole is 0.25cm. The distance from the edge of any large hole inside to the adjacent large hole is 0.25cm. The side wall of the box also has through holes with a diameter of 1.5cm. The shape of the bottom of the box and the shape of the bottom surface of the precast felt are mathematically similar; and the area of ​​the bottom of the box is 1.1 times the area of ​​the bottom of the precast felt; the shape of the top cover of the box and the shape of the bottom surface of the precast felt are mathematically similar; and the area of ​​the top cover of the box is 1.0 times the area of ​​the bottom of the precast felt. (3) Add a curing agent (the curing agent is nitric acid) to the liquid furan resin and preheat it fully at 60°C. The stainless steel box containing the preform was immersed in a furan resin solution. The box containing the needle-punched preform with copper mesh was then immersed in the furan resin solution for 4 minutes. The top cover was then pulled upwards along the height of the box (initially, the top cover and the needle-punched preform were in contact with each other and had a slight interaction force). Immersion continued for 2 minutes. The top cover was then pressed back (until it contacted the needle-punched preform containing the copper mesh without generating mechanical pressure). After pressing back, immersion continued for 2 minutes. This process of pulling and pressing the top cover was repeated twice. The box containing the needle-punched preform with copper mesh was then removed and placed upside down (i.e., inverted) until no resin flowed out. The resulting product was a cuboid, with its length and width, length and height forming right angles, and width and height forming right angles. No obvious pits or wrinkles were observed on the top and bottom surfaces of the product. 98% of the carbon fibers and copper wires introduced perpendicular to the layup direction are observed to be perpendicular. This 98% is a statistical figure. The remaining offset carbon fibers and copper wires have a maximum offset angle of less than 30°.

[0062] Comparative Example 1

[0063] Other conditions were the same as in Example 1, except that the copper-containing carbon fiber prefabricated felt was directly immersed in liquid furan resin containing a curing agent (its composition ratio and dosage were the same as in Example 1) for 16 minutes; the resulting product exhibited a certain degree of deformation, and this displacement was not in one direction, with the displacement angle generally ranging from 5 to 60°, showing extremely high randomness. (e.g.) Figure 4 (As shown).

[0064] Comparative Example 2

[0065] All other conditions are the same as in Example 1, except that:

[0066] (2) Place the above preform into a stainless steel box with openings on all four sides and bottom, for later use. The diameter of all openings is 1.5cm. The top cover of the box cannot be moved, and the distance between the top cover of the box and the preform is 5cm. Immerse for 16 minutes. The resulting product has a certain degree of deformation, and this offset has a certain degree of randomness, but it is a significant improvement compared to Comparative Example 1, and the offset is generally 5~45° (e.g., Figure 5 (As shown).

[0067] Comparative Example 3

[0068] Other conditions are the same as in Example 1, except that: (2) the above preform is placed in a stainless steel box with holes on all four sides and bottom, for later use. The top cover of the stainless steel box is provided with a conical hole, with the small hole facing outward and the large hole facing inward; the diameter of the large hole is A, where A is 2.5cm, and the diameter of the small hole is 2cm. The distance from the edge of any large hole inside to the adjacent large hole is 0.5cm. The holes at the bottom of the stainless steel box are also conical holes, with the small hole facing inward and the large hole facing outward; the diameter of the large hole is A, where A is 2.5cm, and the diameter of the small hole is 2cm. The distance from the edge of any large hole inside to the adjacent large hole is 0.5cm. The side wall of the box is also provided with a through hole, the diameter of which is 2.5cm. The resulting product is as follows Figure 6 As shown.

Claims

1. A method for shaping a needle-punched carbon / carbon-copper composite felt, characterized in that, Includes the following steps: Step 1 Carbon fiber nonwoven fabric and carbon fiber mesh are sequentially stacked in the following order: 0° carbon fiber nonwoven fabric, copper mesh, carbon fiber mesh, 90° carbon fiber nonwoven fabric, copper mesh, carbon fiber mesh, and 0° carbon fiber nonwoven fabric. Carbon fiber bundles are introduced into the direction perpendicular to the layup using a relay needle punching method to produce a needle-punched prefabricated felt containing copper mesh. Step Two The needle-punched precast felt containing copper mesh is placed in box C, which has openings on all four sides and at the bottom, for later use; the top cover of box C can move up and down along the height of the box, and the area of ​​the top cover is greater than 2 / 3 of the area of ​​the bottom of the box; the top cover also has through holes; the holes on the top cover of box C are conical holes, with the smaller hole facing outward and the larger hole facing inward; the diameter of the larger hole is A, and A is 0.5~1.5cm, and the diameter of the smaller hole is 0.5~0.75A; the distance from the edge of any large hole inside to the adjacent large hole is less than 0.3cm; The holes on the bottom and side walls of box C are conical holes, with the smaller hole facing inward and the larger hole facing outward; the diameter of the larger hole is A, and A ranges from 0.5 to 1.5 cm; the diameter of the smaller hole is 0.5 to 0.75A; the distance from the edge of any large hole inside to the adjacent large hole is less than 0.3 cm; Step 3 Add a curing agent to liquid furan resin and preheat it fully at 50~70℃; immerse box C containing the needled preformed felt with copper mesh in the furan resin solution, pull it along the height of the box and press the top cover back at least 3 times; and during the pressing back operation, at least once the top cover comes into contact with the needled preform containing copper mesh; then remove the box containing the needled preform containing copper mesh and let it stand until no resin flows out. Step Four Place the stainless steel box from step three into an oven at 160~200℃ and remove it after 90~150 minutes when the resin has cured. A pre-fabricated felt containing resin and copper mesh was obtained; Step 5 The pre-made felt containing resin and copper mesh obtained in step four is placed in box C with openings on all four sides and bottom. Steps three and four are repeated to obtain a pre-made felt containing resin and copper mesh that has been impregnated and cured twice. Step Six The pre-made felt containing resin and copper mesh obtained from step five, which has undergone secondary impregnation and curing, is placed in a carbonization furnace and heated to above 800°C for carbonization treatment, thus obtaining a shaped needle-punched carbon / carbon-copper felt body.

2. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: Box C is made of stainless steel.

3. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: The holes on the top cover of the box are conical holes, with the smaller hole facing outwards and the larger hole facing inwards; the diameter of the larger hole is A, which ranges from 0.9 to 1.2 cm, and the diameter of the smaller hole is 0.5 to 0.55A; the distance from the edge of any one of the larger holes to the adjacent larger hole is less than 0.3 cm.

4. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: The holes at the bottom of the box are conical, with the smaller hole facing inward and the larger hole facing outward; the diameter of the larger hole is A, which ranges from 0.9 to 1.2 cm, and the diameter of the smaller hole ranges from 0.5 to 0.55A; the distance from the edge of any one of the larger holes to the adjacent larger hole is less than 0.3 cm.

5. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: The contact area between the downward or upward pressure rod connected to the top cover of box C and the top cover of box C is greater than or equal to 0.3 times the area of ​​the top cover of box C and less than the area of ​​the top cover of box C.

6. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: The shape of the bottom of the box and the shape of the bottom surface of the precast felt are mathematically similar; and the area of ​​the bottom of the box is 1.01 to 1.2 times the area of ​​the bottom of the precast felt. The shape of the box top and the shape of the precast felt bottom are mathematically similar; and the area of ​​the box top is 0.99 to 1.005 times the area of ​​the precast felt bottom.

7. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: The length, width, and height of the needle-punched preform containing copper mesh are (1000-1200) mm × (300-400) mm × (40-45) mm; the volume percentage of copper in the needle-punched preform containing copper mesh is 1-30%; the curing agent is selected from at least one of phosphoric acid, sulfuric acid, and nitric acid.

8. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: Add a curing agent to liquid furan resin and preheat it fully at 50~70℃; immerse the box containing the needle-punched pre-fabricated felt with copper mesh in the furan resin solution for at least 3 minutes, then pull the top cover along the height of the box and continue immersing for 1-2 minutes, then press the top cover back, and immerse for another 1-2 minutes. Repeat the operation of pulling and pressing the top cover 2-4 times, then take out the box containing the needle-punched pre-fabricated felt with copper mesh and let it stand until no resin flows out.

9. The method for shaping a needle-punched carbon / carbon-copper composite felt according to claim 1, characterized in that: After the impregnation is completed in step three, take out the box containing the needle-punched pre-fabricated felt body with the copper mesh, place it with the top side down until no resin flows out; In step four, the oven is first heated to 160~200℃, and then the box with the needled preform containing copper mesh from step three is placed in it and dried to obtain a preformed felt containing resin and copper mesh. In step five, the prefabricated felt containing resin and copper mesh obtained in step four is placed in box C with openings on all four sides and bottom, with the bottom surface of the prefabricated felt in step three as the top surface of step five and the top surface of the prefabricated felt in step three as the bottom surface of step five. Steps three and four are repeated to obtain a prefabricated felt containing resin and copper mesh that has been impregnated and cured twice.

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