Preparation method of composite net tire and application of composite net tire in preparation of prefabricated body

Abstract

The invention discloses a preparation method of a composite net tire and application of the composite net tire in preparation of a prefabricated body, and belongs to the technical field of prefabricated body processing, and the preparation method comprises the steps of preparation of the composite net tire, preparation of a base layer, preparation of a middle layer, prefabricated body forming, machining, gradient high-temperature treatment and the like. The continuous multidirectional long fiber structure is formed by arranging the winding layers with different winding angles, when the continuous multidirectional long fiber structure is subjected to external force, the angle winding layers can decompose oblique force into axial force and annular force, a carbon cloth reinforcing layer and axial filaments are replaced to play a reinforcing role, the structural strength of the prefabricated body is improved, and layering is effectively reduced; a liquid resin infiltrating-infiltrating extrusion-liquid resin re-infiltrating process is introduced, so that the content and the uniformity of the resin in the net tire are improved; a semi-finished preform is subjected to graded gradient high-temperature treatment, the gas release rate is controlled, carbon nanotubes are introduced into the preform, and the carbon nanotubes form an interconnected micro-channel for exhausting, so that the layering risk can be reduced.

Description

Technical Field

[0001] This invention relates to a preform processing method, and more particularly to a method for preparing a composite mesh and its application in the preparation of preforms. Background Technology

[0002] Support rods, muffles, and insulation cylinders, among other thermal field structural components, require resistance to high temperatures and pressures. Existing materials are generally graphite, but graphite raw materials are expensive and have limited strength. Therefore, carbon / carbon composite materials are the best choice. Currently, the domestic market for carbon / carbon materials is monopolized by foreign suppliers. Few domestic manufacturers can produce qualified carbon / carbon composite support rods and insulation cylinders using the impregnation and winding process. This is because the matrix material of carbon / carbon composite materials is pyrolytic carbon, formed through processes such as resin liquid-phase densification and high-temperature pyrolysis. The winding process involves layering carbon cloth, mesh, and carbon fibers. Due to uneven resin distribution, gas generation and pressure accumulation from resin pyrolysis, and weak interfacial bonding, the product often exhibits delamination. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a method for preparing composite mesh and its application in the preparation of preforms. By employing a resin impregnation-extrusion-re-impregnation liquid resin process and introducing microchannels, the interlayer bonding strength of the mesh product is improved, and delamination is significantly reduced.

[0004] Technical solution: The present invention provides a method for preparing a composite mesh, the specific preparation steps of which are as follows: the mesh made of short fibers is impregnated with liquid resin through an impregnation and extrusion device to form a resin-containing mesh; carbon nanotube dispersion is sprayed onto the surface of the resin-containing mesh to form a composite mesh.

[0005] Preferably, the short fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber; the liquid resin is one or more combinations of polysilazane, polycarbosilane, epoxy resin, phenolic resin, and urea-formaldehyde resin; the carbon nanotube dispersion has a liquid-to-solid content of 2-8%, a carbon nanotube length of 20-100 μm, a carbon nanotube outer diameter of 10-80 nm, and a spraying density of 1.0-5.0 g / m³. 2 .

[0006] Preferably, the impregnation and extrusion device includes an impregnation frame, an impregnation tank, a power drive mechanism, a tensioning mechanism, a guide roller assembly, a pressure roller assembly, an idler roller assembly, a pressure roller lifting and adjusting mechanism, an idler roller lifting and adjusting mechanism, a guide roller lifting and adjusting mechanism, and a support component; The impregnation tank is located at the bottom of the inner side of the impregnation frame and is used to contain liquid resin. The pressure roller assembly and the idler roller assembly are arranged on the impregnation frame along the traveling direction of the tire mesh and are located above the impregnation tank; the pressure roller lifting and adjusting mechanism includes two sets of transmission connections at both ends of the pressure roller assembly and correspondingly arranged at both ends of the impregnation frame, used to drive the pressure roller assembly to move vertically to adjust the gap between it and the idler roller assembly; the idler roller lifting and adjusting mechanism includes two sets of transmission connections at both ends of the idler roller assembly and correspondingly arranged at both ends of the impregnation frame, used to drive the idler roller assembly to move vertically to adjust the gap between it and the pressure roller assembly; The guide roller assembly is correspondingly disposed at the feed end of the idler roller assembly and located above the impregnation tank, with its two ends respectively connected to the impregnation frame; the support member is disposed parallel to and below the guide roller assembly, and a gap is formed between the support member and the guide roller assembly for the mesh to pass through; the guide roller lifting and adjusting mechanism includes two sets of transmission connections at both ends of the guide roller assembly and correspondingly disposed at both ends of the impregnation frame, used to drive the guide roller assembly to move vertically, so as to adjust the distance between the guide roller assembly and the support member; The power drive mechanism is connected to the pressure roller assembly, idler roller assembly, and guide roller assembly via a tensioning mechanism, and is used to drive the pressure roller assembly, idler roller assembly, and guide roller assembly to rotate so as to continuously traction the tire.

[0007] Preferably, the pressure roller assembly, the idler roller assembly, and the guide roller assembly all include a roller body and support shafts correspondingly disposed at both ends of the roller body, and a transmission sprocket is connected to the support shaft end on the same side of the pressure roller assembly, the idler roller assembly, and the guide roller assembly.

[0008] Preferably, side baffles are respectively provided at both ends of the immersion frame on the upper side of the immersion tank, and each side baffle has two guide grooves longitudinally parallel along its width direction, and the guide grooves of the two side baffles are correspondingly provided. The pressure roller lifting adjustment mechanism, the idler roller lifting adjustment mechanism, and the guide roller lifting adjustment mechanism all include a slider bearing slidably connected in the guide groove and an adjusting screw arranged along the direction of the guide groove. One end of the adjusting screw is rotatably connected to the side wall of the slider bearing, and the other end of the adjusting screw is threadedly connected to the impregnation frame. Rotating the adjusting screw can drive the slider bearing to move vertically along the guide groove, thereby driving the pressure roller assembly, idler roller assembly, and guide roller assembly to adjust their lifting positions.

[0009] Preferably, the tensioning mechanism includes a tensioning bracket, a U-shaped seat, a tensioning sprocket, and a tensioning screw; The tensioning bracket and the power drive mechanism are fixed to one end of the immersion frame. The U-shaped seat is connected to the tensioning bracket through a tensioning screw. The tensioning sprocket is rotatably installed inside the U-shaped seat. By rotating the tensioning screw, the U-shaped seat can be driven to slide back and forth along the tensioning bracket.

[0010] Preferably, the power drive mechanism includes a drive motor and a matching gearbox. The drive shaft end of the gearbox is connected to a drive sprocket. The drive sprocket is connected to each of the transmission sprockets and tension sprockets via a transmission chain. After the drive motor starts, it can drive the guide roller assembly, pressure roller assembly and idler roller assembly to rotate synchronously through the sprocket and chain transmission.

[0011] Preferably, the supporting member can be a supporting plate or a supporting roller; the bottom of the impregnation tank is provided with a discharge valve for discharging residual liquid resin in the tank; and casters are provided at the four corners of the bottom of the impregnation frame.

[0012] This invention also discloses the application of composite mesh tires in wound preforms, the application comprising the following steps: Step S1, Base layer preparation: The composite mesh is laid outside the processing mold to form a mesh layer. Long fibers are wound around the mesh layer in the circumferential direction along the processing mold to form a circumferential winding layer. The winding angle is adjusted, and the long fibers are wound to form an angle winding layer. During angle winding, one forward winding and one reverse winding are performed at the same and symmetrical angle to form an angle winding layer. Then, the composite mesh layer is laid outside the angle winding layer and needle-punched and hooked. Finally, n layers (n≤1) of circumferential winding layers are laid. Step S2, intermediate layer preparation: continue to alternately lay angled winding layers and composite mesh layers to form an angled winding layer-composite mesh layer-angled winding layer-composite mesh layer structure; after the composite mesh layer is laid, needle punching is performed. The needle punching is performed after laying a single layer of mesh or after laying multiple layers of mesh. Step S3, Precast body forming: Repeat step S2 until the laying thickness reaches the preset thickness, and finally lay a circumferential winding layer and a composite mesh layer, and perform needle-punching and hooking fixation. Step S4, machining: cut and demold to obtain the preform semi-finished product of the required shape; Step S5, gradient high temperature treatment: Under a protective atmosphere, the preform semi-finished product is heated to 200-350℃ at a rate of 1-3℃ / min and held for 3-10h; then heated to 500-1000℃ at a rate of 5-10℃ / min and held for 1-5h to complete the high temperature treatment and obtain the preform finished product. In steps S1-S3, the long fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber; the circumferential winding angle is 90° and the winding tension is 10-20N; the angled winding angle is 15°-75° and the winding tension is 10-20N; the needle punching density is 15-35 needles / cm. 2 The acupuncture speed is 100-200 times / min.

[0013] The present invention also discloses the application of composite mesh in precast slabs, the application comprising the following steps: selecting carbon cloth as in-plane reinforcement material, alternately laying and needle-punching composite mesh and carbon cloth, placing composite mesh between adjacent carbon cloth layers, repeating the above laying and needle-punching process until a predetermined thickness is reached to form a multi-layer composite slab precast body.

[0014] Compared with the prior art, the present invention has the following beneficial effects: (1) During the high-temperature heating process, the resin (such as phenolic resin, epoxy resin, etc.) in the preform undergoes a pyrolysis reaction, which decomposes to generate a large number of small molecule gases (such as H2, CH4, CO, CO2, H2O, etc.). If the gas diffusion channels (pores, fiber gaps) inside the preform are not smooth enough, the small molecule gases will not be able to escape in time, and the gas pressure trapped between layers or inside the preform will rise sharply. When the interlayer gas pressure exceeds the bonding force between layers (the strength of the resin matrix itself and the strength of the fiber / resin interface), it will "spread" the adjacent layers, resulting in delamination. In this invention, carbon nanotubes are introduced into the mesh. The carbon nanotubes are introduced into the mesh during the needle punching process and form a through-hole multi-scale pore channel in the fiber gap during the subsequent heat treatment process, providing a channel for gas to escape and avoiding pressure accumulation that causes delamination. (2) If the preform has poor impregnation, pores, bubbles or resin-rich / resin-poor areas during the resin impregnation process, the strength of these areas will be lower and they are more likely to become stress concentration points and delamination initiation points. Insufficient resin content between layers is especially likely to cause delamination. This invention creatively introduces the impregnation resin-impregnation extrusion-re-impregnation liquid resin process, which improves the content and uniformity of the impregnation resin of the mesh preform and effectively reduces the delamination phenomenon caused by resin unevenness. (3) The impregnation and extrusion device of the present invention has a good impregnation effect. The synergistic operation of "impregnation resin + extrusion + impregnation resin" can improve the impregnation effect. The liquid resin content can be increased by more than 1 times compared with soaking alone in the same time. It can be seen that the device can accelerate the penetration of liquid resin and shorten the impregnation time. The extrusion operation of the impregnated mesh is achieved by the cooperation of guide roller and support component, which accelerates the penetration of liquid resin, shortens the impregnation time, and realizes the recovery of excess liquid resin, improving the impregnation uniformity. The device is equipped with guide roller and support component. By adjusting the guide roller, the distance between the guide roller and support component and the depth of immersion in the impregnation tank can be adjusted to adapt to products of different thicknesses, so as to realize the full absorption of liquid resin by the roll material and the absorption uniformity. The device uses support component and guide roller to eliminate the need to open holes in the impregnation tank, avoid leakage caused by poor sealing, and reduce the equipment installation and maintenance costs. (4) The processing method of the present invention forms a continuous long fiber structure by setting winding layers with different winding angles to replace the axial winding and carbon cloth reinforcement layer in the traditional process. It is equivalent to weaving a multi-directional fabric structure directly on the mesh. When subjected to external force, the angle winding layer will decompose the oblique force into axial and circumferential forces, replacing the carbon cloth reinforcement layer and axial wire to play a strengthening role, improving the strength of the prefabricated structure and effectively reducing delamination. (5) Excessive heating rate will accelerate the pyrolysis reaction rate of resin, resulting in a surge in the amount of gas generated per unit time, greatly increasing the possibility that the gas cannot be discharged in time and accumulates; at the same time, rapid heating also aggravates thermal adaptation stress, causing product delamination; the present invention controls the gas release rate through a graded high-temperature treatment process, which can reduce the risk of delamination. Attached Figure Description

[0015] Figure 1 This is a flowchart of the processing method for preparing the composite mesh preform of the present invention. Figure 2 This is a first-view perspective three-dimensional structural diagram of the impregnation and extrusion device of the present invention; Figure 3 for Figure 2 A two-dimensional structural diagram of the intermediate immersion extrusion device from a second perspective. Figure 4 for Figure 2 Schematic diagram of the layout structure of the support components and guide roller assembly in the intermediate immersion tank; Figure 5 for Figure 2 Schematic diagram of the layout structure of the guide roller assembly, pressure roller assembly, idler roller assembly and their end power drive mechanism; Figure 6 for Figure 3 A schematic diagram of the layout structure of the guide roller assembly, pressure roller assembly, idler roller assembly and their end lifting and adjusting mechanisms.

[0016] Figure Descriptions: 100. Impregnation and extrusion device; 1. Impregnation frame; 2. Impregnation tank; 3. Netting; 4. Power drive mechanism; 5. Drive sprocket; 6. Transmission chain; 7. Tensioning mechanism; 71. Tensioning bracket; 72. U-shaped seat; 73. Tensioning sprocket; 74. Tensioning screw; 8. Caster wheel; 9. Guide roller assembly; 10. Pressure roller assembly; 11. Idler roller assembly; 12. Pressure roller lifting and adjusting mechanism; 13. Idler roller lifting and adjusting mechanism; 14. Guide roller lifting and adjusting mechanism; 15. Discharge valve; 16. Side baffle; 17. Guide groove; 18. Transmission sprocket; 19. Adjusting screw; 20. Sliding bearing; 21. Supporting component. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following description is provided in conjunction with the appendix. Figures 1-6The technical solutions of the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0018] This invention discloses a method for preparing a composite mesh, the specific preparation steps of which are: placing short fibers into a mesh box, and forming the mesh using a carding device and airflow to obtain a mesh; subjecting the mesh to a resin impregnation-extrusion-re-impregnation with liquid resin process to form a resin-containing mesh; and spraying a carbon nanotube dispersion onto the surface of the resin-containing mesh to form a composite mesh. The mesh has a basis weight of 60-150 g / m². 2 The short fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber; the liquid resin is one or more combinations of polysilazane, polycarbosilane, epoxy resin, phenolic resin, and urea-formaldehyde resin, and the viscosity of the liquid resin during wetting is 100-250 mPa·s (25℃); the solid content of the carbon nanotube dispersion is 2-8%, the carbon nanotube dispersion is a stable dispersion system, its dispersion medium is a polar solvent or an aqueous system, the viscosity of the carbon nanotube dispersion is 10-25 mPa·s, the length of the carbon nanotubes is 20-100 μm, the outer diameter of the carbon nanotubes is 10-80 nm, and the spraying density is 1.0-5.0 g / m³. 2 .

[0019] like Figures 2-6 As shown, the present invention also discloses an impregnation and extrusion device 100 for the preparation of the above-mentioned composite mesh tire. The impregnation and extrusion device 100 includes an impregnation frame 1, an impregnation tank 2, a guide roller assembly 9, a support member 21, a pressure roller assembly 10, an idler roller assembly 11, a pressure roller lifting and adjusting mechanism 12, an idler roller lifting and adjusting mechanism 13, a guide roller lifting and adjusting mechanism 14, a tensioning mechanism 7, and a power drive mechanism 4.

[0020] like Figure 2 As shown, the impregnation frame 1 is a frame structure welded from square steel or steel pipes. It serves as the main structure of the impregnation extrusion device and is used to install and support various functional components. The impregnation frame 1 is equipped with casters 8 at its four bottom corners. This device is flexible to move, lightweight, and compact, and can be moved manually or with a small forklift. It requires no fixed installation, reducing factory space occupation and adapting to the layout adjustment needs of small-batch, multi-variety operations.

[0021] An impregnation tank 2 is provided at the bottom of the inner side of the impregnation frame 1. The impregnation tank 2 is used to contain liquid resin. The liquid resin can be absorbed when the mesh 3 passes through the impregnation tank 2.

[0022] like Figures 4-6As shown, the pressure roller assembly 10 and the idler roller assembly 11 are arranged on the impregnation frame along the travel direction of the roll material and are located above the impregnation tank 2. The guide roller assembly is correspondingly arranged at the feed end of the idler roller assembly 11 and is located above the impregnation tank 2, with its two ends connected to the impregnation frame. The support member 21 is arranged parallel to and correspondingly below the guide roller assembly 9, and a gap is formed between the support member 21 and the guide roller assembly 9 for the wire mesh 3 to pass through. The support member 21 can be a support plate or a support roller. If a support roller is used, the support roller rotates as the roll material passes between the support member 21 and the guide roller assembly 10, thereby reducing the resistance of the roll material. The pressure roller assembly 10, the idler roller assembly 11, and the guide roller assembly 9 all include a roller body and support shafts correspondingly arranged at both ends of the roller body, and a drive sprocket 18 is connected to the support shaft end on the same side of the pressure roller assembly 10, the idler roller assembly 11, and the guide roller assembly 9. It should be noted that during the process of entering the impregnation and extrusion device, the mesh first passes through the gap between the lower side of the guide roller assembly and the support member 21, and then passes between the pressure roller assembly and the idler roller assembly. This device is equipped with guide rollers and support members. By adjusting the height of the guide rollers, the distance between the guide rollers and the support members, as well as the depth of immersion in the impregnation tank, can be adjusted to accommodate products of different thicknesses, achieving full and uniform absorption of liquid resin by the mesh 3. The use of support members and guide rollers in this device eliminates the need for opening holes in the impregnation tank, avoiding leakage due to poor sealing, and reducing equipment installation and maintenance costs. It should be noted that the diameter of the guide roller assembly can be different from the diameter of the pressure roller assembly and the idler roller assembly; the diameter of the pressure roller assembly and the idler roller assembly is the same, and they are arranged vertically correspondingly. The gap between the pressure roller and the idler roller in this device is adjustable.

[0023] like Figures 3-6As shown, the pressure roller lifting adjustment mechanism 12 includes two sets of transmission connections to both ends of the pressure roller assembly 10 and correspondingly arranged at both ends of the impregnation frame 1, used to drive the pressure roller assembly 10 to move vertically to adjust the gap between it and the idler roller assembly 11; the idler roller lifting adjustment mechanism 13 includes two sets of transmission connections to both ends of the idler roller assembly 11 and correspondingly arranged at both ends of the impregnation frame 1, used to drive the idler roller assembly 11 to move vertically to adjust the gap between it and the pressure roller assembly 10; the guide roller lifting adjustment mechanism 14 includes two sets of transmission connections to both ends of the guide roller assembly 9 and correspondingly arranged at both ends of the impregnation frame 1, used to drive the guide roller assembly 9 to move vertically to adjust the distance between the guide roller assembly 9 and the support member 21. Specifically, side baffles 16 are respectively provided at both ends of the impregnation frame 1 on the upper side of the impregnation tank 2, and each side baffle 16 has two guide grooves 17 longitudinally parallel along its width direction, and the guide grooves 17 of the two side baffles 16 are correspondingly arranged. The pressure roller lifting adjustment mechanism 12, the idler roller lifting adjustment mechanism 13, and the guide roller lifting adjustment mechanism 14 all include a slider bearing 20 slidably connected in the guide groove 17 and an adjusting screw 19 arranged along the direction of the guide groove 17. One end of the adjusting screw 19 is rotatably connected to the side wall of the slider bearing 20, and the other end of the adjusting screw is threadedly connected to the impregnation frame 1. Rotating the adjusting screw can drive the slider bearing to move vertically along the guide groove 17, thereby driving the pressure roller assembly 10, the idler roller assembly 11, and the guide roller assembly 9 to adjust their lifting positions. The pressure roller lifting adjustment mechanism and the idler roller lifting adjustment mechanism can precisely adjust the extrusion gap between the pressure roller and the idler roller to adapt to different thicknesses of mesh products. The extrusion gap is adjustable to avoid dripping on the product surface. The guide roller lifting adjustment mechanism 14 is used to adjust the vertical height of the guide roller assembly 9, thereby adjusting the distance between the guide roller and the support member 21 and the depth of immersion in the impregnation tank to adapt to different thicknesses of mesh products, achieving full absorption and uniform absorption of liquid resin by the mesh.

[0024] like Figure 5 As shown, the tensioning mechanism 7 includes a tensioning bracket 71, a U-shaped seat 72, a tensioning sprocket 73, and a tensioning screw 74. The tensioning bracket 71 and the power drive mechanism 4 are fixed to one end of the immersion frame 1. The U-shaped seat 72 is connected to the tensioning bracket 71 through the tensioning screw 74. The tensioning sprocket 73 is rotatably installed in the U-shaped seat 72. By rotating the tensioning screw 74, the U-shaped seat 72 can be driven to slide back and forth along the tensioning bracket 71, thereby adjusting the horizontal position of the tensioning sprocket 73 to control the tension of the transmission chain 6.

[0025] like Figure 2 and Figure 5As shown, the power drive mechanism 4 is connected to the pressure roller assembly 10, the idler roller assembly 11, and the guide roller assembly 9 via the tensioning mechanism 7, and is used to drive the pressure roller assembly 10, the idler roller assembly 11, and the guide roller assembly 9 to rotate so as to continuously traction the mesh tire. Specifically, the power drive mechanism 4 includes a drive motor and a matching gearbox. The drive sprocket 5 is connected to the power shaft end of the gearbox. The drive sprocket 5 is connected to each of the transmission sprockets 18 and the tensioning sprocket 73 via the transmission chain 6. After the drive motor starts, it can drive the guide roller assembly 9, the pressure roller assembly 10, and the idler roller assembly 11 to rotate synchronously through the sprocket and chain transmission.

[0026] like Figure 4 and Figure 6 As shown, the lower end of the slot on the side wall of the impregnation tank 2 through which the support shaft passes is higher than the maximum liquid level in the impregnation tank 2, and the lower edge of the roller body is immersed in the liquid resin when the guide roller assembly 9 is at its lowest position, ensuring that the mesh is fully impregnated with the liquid resin.

[0027] like Figures 3-4 As shown, the bottom of the impregnation tank 2 is equipped with a discharge valve 15 for discharging residual liquid resin in the tank. This device is energy-saving and environmentally friendly. The discharge valve can recover residual liquid resin, reduce raw material waste, and lower environmental treatment costs.

[0028] This invention utilizes a guide roller and support components to perform an extrusion operation on the impregnated roll material. The coordinated operation of "impregnating liquid resin - impregnating and extruding - re-impregnating liquid resin" improves the impregnation effect, increasing the liquid resin content by more than double compared to soaking alone in the same timeframe. This demonstrates that the equipment accelerates liquid resin penetration and shortens impregnation time. The gap between the pressure roller and the support roller is adjustable. The pressure roller lifting and adjusting mechanisms and the support roller lifting and adjusting mechanisms allow for precise adjustment of the extrusion gap between the pressure roller and the support roller, adapting to different thicknesses of the mesh and enabling the recovery of excess liquid resin, preventing dripping on the product surface and improving the uniformity of resin impregnation. The device is easy to assemble and disassemble; each component adopts a modular design, making disassembly and assembly simple and facilitating maintenance and repair.

[0029] The working method or working principle of the impregnation and extrusion device of the present invention: First, move the device to the working position and adjust the placement angle of the device using the casters 8 to ensure smooth feeding and discharging of the mesh tire.

[0030] Next, liquid resin is injected into the impregnation tank 2, ensuring the liquid level does not exceed the lower end of the guide groove of the side baffle or is injected to a preset height. The mesh 3 is then passed sequentially through the gap between the guide roller assembly 9 and the support member 21, and the gap between the pressure roller assembly 10 and the idler roller assembly 11, exiting from the end of the impregnation and extrusion device. The adjusting screws of the two sets of pressure roller lifting adjustment mechanisms 12 are rotated synchronously, driving the pressure roller assembly 10 to move vertically through the slider bearing, while ensuring the pressure roller assembly 10 is horizontal; the adjusting screws of the two sets of idler roller lifting adjustment mechanisms 13 are rotated synchronously to adjust the height of the idler roller assembly 11, thus adjusting the extrusion gap in conjunction with the pressure roller assembly 10; the adjusting screw of the guide roller lifting adjustment mechanism 14 is rotated synchronously, driving the guide roller assembly 9 to move vertically through the slider bearing, while ensuring the guide roller assembly 9 is horizontal, thus adjusting the extrusion gap in conjunction with the support member 21. The tensioning screw 74 of the tensioning mechanism 7 is rotated to adjust the horizontal position of the tensioning sprocket 73, ensuring the transmission chain 6 maintains a suitable tension.

[0031] Next, the drive motor of the power drive mechanism 4 is started, the drive motor speed is set, and the drive motor drives the drive sprocket 5 to rotate, which in turn drives each transmission sprocket 18 to rotate through the transmission chain 6, thus traction the mesh tire 3 to move forward continuously. During the movement, the mesh tire 3 is first soaked in liquid resin in the impregnation tank 2 at the front end of the guide roller assembly 9, then impregnated and squeezed by the guide roller assembly 9 and the support member 21, and then soaked again in liquid resin in the impregnation tank 2 at the rear end of the guide roller assembly 9. Finally, under the pressure of the pressure roller assembly 10 and the idler roller assembly 11, excess liquid resin is squeezed out, avoiding liquid resin dripping from the surface of the mesh tire.

[0032] Finally, after the operation is completed, turn off the drive motor and discharge the residual liquid resin in the impregnation tank 2 through the discharge valve 15 for recycling. If disassembly and maintenance are required, the drive chain 6, pressure roller assembly 10, idler roller assembly 11 and other components can be removed in sequence.

[0033] like Figure 1 As shown, this invention discloses the application of composite mesh tires in wound preforms, including the following steps: Step S1, Base Layer Preparation: A composite mesh is laid outside the processing mold to form a mesh layer. Long fibers are circumferentially wound around the mesh layer along the mold to form a circumferential winding layer. The winding angle is adjusted, and the long fibers are continued to form an angled winding layer. During angled winding, one forward winding and one reverse winding at the same and symmetrical angle constitute one angled winding layer. A composite mesh layer is then laid outside the angled winding layer and needle-punched. Finally, n layers (n≤1) of circumferential winding layers are laid. The long fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber. The winding angle for circumferential winding is 90°, and the winding tension is 10-20N. The winding angle for angled winding is 15°-75°, and the winding tension is 10-20N. The needle-punching density is 15-35 needles / cm.2 The acupuncture speed is 100-200 times / min.

[0034] Step S2, Intermediate Layer Preparation: Continue to alternately lay angled winding layers and composite mesh layers to form an angled winding layer-composite mesh layer-angled winding layer-composite mesh layer structure; after laying the composite mesh layer, needle punching is performed, which can be done after laying a single layer of mesh or after laying multiple layers of mesh; the long fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber; the circumferential winding angle is 90° and the winding tension is 10-20N; the angled winding angle is 15°-75° and the winding tension is 10-20N; the needle punching density is 15-35 needles / cm. 2 The acupuncture speed is 100-200 times / min.

[0035] Step S3, Preform Forming: Repeat step S2 until the laid thickness reaches the preset thickness. Finally, lay a circumferential winding layer and a composite mesh layer, and fix them by needle punching. The long fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber. The circumferential winding angle is 90° and the winding tension is 10-20N. The angled winding angle is 15°-75° and the winding tension is 10-20N. The needle punching density is 15-35 needles / cm. 2 The acupuncture speed is 100-200 times / min.

[0036] Step S4, machining: cut and demold to obtain the preform semi-finished product of the required shape; Step S5, gradient high temperature treatment: Under a protective atmosphere, the preform semi-finished product is heated to 200-350℃ at a rate of 1-3℃ / min and held for 3-10h; then heated to 500-1000℃ at a rate of 5-10℃ / min and held for 1-5h to complete the high temperature treatment and obtain the preform finished product.

[0037] It should be noted that the processing setup used in the preform processing method of the present invention can adopt conventional processing devices in the prior art, which typically include a worktable with a rotatable support shaft on the worktable. The processing mold is fixedly clamped on the support shaft. The rotation of the support shaft can drive the processing mold to rotate so as to facilitate spinning and winding. The rotation speed of the shaft is also the rotation speed of the processing mold. The winding device and the needle punching device can both be implemented using existing technologies, and will not be described in detail here.

[0038] The following embodiments further illustrate the processing method of this invention.

[0039] Example 1: This example uses the preparation of a 40-inch crucible preform as an example. The dimensions of the crucible preform are an outer diameter of 1095 mm, an inner diameter of 1055 mm, and a height of 220 mm. A processing mold is made using this size crucible. The shape of the processing mold can be circular, elliptical, cocoon-shaped, etc., to meet the processing requirements of different shape preforms. The specific processing method of this crucible preform includes the following steps: (I) Preparation of composite mesh: Quartz fibers with SiO2 purity ≥ 99.95% are placed in a mesh box and formed into a mesh using a carding device and airflow. The mesh weight is 150 g / m². 2 The mesh was impregnated with polysilazane using an impregnation and extrusion device, followed by impregnation and extrusion, and then impregnation with polysilazane again. The resin viscosity was 180 mPa·s (25℃), forming a resin-containing mesh. The impregnation time was 10 min. After impregnation, the mesh was squeezed dry and weighed to obtain a basis weight of 780 g / m². 2 The weight gain after impregnation was 420%. A carbon nanotube dispersion was sprayed onto the resin-containing mesh surface. The dispersion had a viscosity of 18 mPa·s, an outer diameter of 60-80 nm, a length of 70-100 μm, a solid content of 8%, and a spraying density of 5.0 g / m³. 2 This forms a composite mesh tire.

[0040] (II) Base Layer Preparation: The composite mesh is laid outside the processing mold to form a mesh layer. Quartz fibers with a SiO2 purity ≥ 99.95% are circumferentially wound around the mesh layer at a 90° angle along the processing mold to form a circumferential winding layer. The winding angle is adjusted to 75°, and long fibers are continued to form an angled winding layer. The winding tension of the long fibers is 10N. During angled winding, one forward winding and one reverse winding at the same and symmetrical angle constitute one angled winding layer. Then, the composite mesh layer is laid outside the angled winding layer and needle-punched. The needle-punching density is 35 needles / cm. 2 The needle-punching speed is 100 times / min. Finally, lay one more circumferential winding layer.

[0041] (III) Intermediate Layer Preparation: Continue laying the bottom angled winding layer with a winding tension of 10N. Alternately lay the composite mesh layer and the angled winding layer to form a stacked structure of angled winding layer-mesh layer-angled winding layer-mesh layer. Needle punching and hooking are carried out simultaneously. Needle punching and hooking can be done immediately after each layer of composite mesh layer is laid, or it can be completed in a concentrated manner after laying multiple layers of composite mesh layer. The needle punching density is 35 needles / cm. 2 The acupuncture speed is 100 times / min.

[0042] (IV) Preform Forming: The intermediate layer is prepared in a cyclical and repeated manner, totaling 11 layers of angled winding layers and 11 layers of mesh. The winding angles of the angled winding layers from the inside out are 60°, 75°, 45°, 30°, 45°, 30°, 45°, 30°, 60°, 75°, and 75° (each angle is symmetrically wound on both sides as a group). Finally, a circumferential winding layer and a composite mesh layer are laid, and needle-punched and hooked for fixation. The circumferential winding angle is 90°, the winding tension is 10N, and the needle-punching density is 35 needles / cm. 2 The needle puncture speed is 100 times / min to complete the laying of the precast body.

[0043] (v) Machining: Cut and demold to obtain the prefabricated semi-finished product of the required shape.

[0044] (vi) Gradient high temperature treatment: Under a protective atmosphere, the preform semi-finished product is heated to 350℃ at a rate of 3℃ / min and cured for 10h; then heated to 1000℃ at a rate of 10℃ / min and kept at that temperature for 5h to complete the high temperature treatment and obtain the preform finished product.

[0045] The preform semi-finished product obtained in this embodiment has a tensile strength of 8 MPa, a T-peel strength of 7.6 N / mm, and an interlaminar shear strength of 20 MPa after high-temperature treatment.

[0046] Example 2: This example uses the preparation of a 36-inch crucible preform as an example. The dimensions of the crucible preform are 978mm outer diameter, 941mm inner diameter, and 210mm height. A processing mold is made using this size crucible. The shape of the processing mold can be circular, elliptical, cocoon-shaped, etc., to meet the processing requirements of different shape preforms. The specific processing method of this crucible preform includes the following steps: (I) Preparation of composite mesh: T700 carbon fiber is placed in a mesh box and formed into a mesh using a carding device and airflow to obtain a mesh with a basis weight of 100g / m². 2 The mesh was impregnated with phenolic resin through an impregnation and extrusion device, followed by impregnation and extrusion, and then impregnation with phenolic resin again. The resin viscosity was 140 mPa·s (25℃), forming a resin-containing mesh. The impregnation time was 5 minutes. After impregnation, the mesh was squeezed dry and weighed to obtain a basis weight of 497 g / m². 2 The weight gain after impregnation was 397%. A carbon nanotube dispersion was sprayed onto the resin-containing mesh surface. The dispersion had a viscosity of 15 mPa·s, an outer diameter of 20-50 nm, a length of 50-70 μm, a solid content of 5%, and a spraying density of 3.0 g / m³. 2 This forms a composite mesh tire.

[0047] (II) Base Layer Preparation: The composite mesh is laid outside the processing mold to form a mesh layer. T700 carbon fiber is then wound circumferentially around the mesh layer at a 90° angle along the processing mold to form a circumferential winding layer. The winding angle is adjusted to 75°, and the long fibers are continued to form an angled winding layer. The winding tension of the long fibers is 15N. During angled winding, one forward winding and one reverse winding at the same and symmetrical angle constitute one angled winding layer. Then, the composite mesh layer is laid outside the angled winding layer and needle-punched. The needle-punching density is 25 needles / cm. 2 The needle-punching speed is 150 times / min. Finally, lay one more circumferential winding layer.

[0048] (III) Intermediate Layer Preparation: Continue laying the bottom angled winding layer with a winding tension of 15N. Alternately lay the composite mesh layer and the angled winding layer to form a stacked structure of angled winding layer-mesh layer-angled winding layer-mesh layer. Needle punching and hooking are carried out simultaneously. Needle punching and hooking can be done immediately after each layer of composite mesh layer is laid, or it can be completed in a concentrated manner after laying multiple layers of composite mesh layer. The needle punching density is 25 needles / cm. 2 The acupuncture speed is 150 times / min.

[0049] (IV) Preform Forming: The intermediate layer is prepared in a cyclical and repeated manner, totaling 13 layers of angled winding layers and 13 layers of mesh layer. The winding angles of the angled winding layers from the inside out are 60°, 75°, 60°, 45°, 30°, 45°, 30°, 45°, 30°, 45°, 30°, 60°, and 75° (each angle is symmetrically wound on both sides as a group). Finally, a circumferential winding layer and a composite mesh layer are laid, and needle-punched and hooked for fixation. The circumferential winding angle is 90°, the winding tension is 15N, and the needle-punching density is 25 needles / cm. 2 The needle puncture speed is 150 times / min to complete the laying of the precast body.

[0050] (v) Machining: Cut and demold to obtain the prefabricated semi-finished product of the required shape.

[0051] (vi) Gradient high temperature treatment: Under a protective atmosphere, the preform semi-finished product is heated to 250°C at a rate of 1°C / min and cured for 6 hours; then heated to 800°C at a rate of 5°C / min and kept at that temperature for 3 hours to complete the high temperature treatment and obtain the preform finished product.

[0052] The preform semi-finished product obtained in this embodiment has a tensile strength of 7 MPa, a T-peel strength of 4.3 N / mm, and an interlaminar shear strength of 15 MPa after high-temperature treatment.

[0053] Example 3: This example uses the preparation of a 32-inch crucible preform as an example. The dimensions of the crucible preform are an outer diameter of 890 mm, an inner diameter of 845 mm, and a height of 200 mm. A processing mold is made using this size crucible. The shape of the processing mold can be circular, elliptical, cocoon-shaped, etc., to meet the processing requirements of different shape preforms. The specific processing method of this crucible preform includes the following steps: (I) Preparation of composite mesh: Ordinary ceramic fibers with an operating temperature of approximately 1000-1200℃ are placed in a mesh box and formed into a mesh using a carding device and airflow. The mesh weight is 60 g / m². 2 The mesh was impregnated with epoxy resin using an impregnation and extrusion device, followed by impregnation and extrusion, and then impregnation with epoxy resin again. The resin viscosity was 220 mPa·s (25℃), forming a resin-containing mesh. The impregnation time was 2 minutes. After impregnation, the mesh was squeezed dry and weighed to obtain a basis weight of 252 g / m². 2 The weight gain after impregnation was 320%. A carbon nanotube dispersion was sprayed onto the resin-containing mesh surface. The dispersion had a viscosity of 12 mPa·s, an outer diameter of 10-20 nm, a length of 20-50 μm, a solid content of 2%, and a spraying density of 1.0 g / m³. 2 This forms a composite mesh tire.

[0054] (II) Base Layer Preparation: The composite mesh is laid outside the processing mold to form a mesh layer. Ordinary ceramic fibers are circumferentially wound around the mesh layer at a 90° angle along the processing mold to form a circumferential winding layer. The winding angle is adjusted to 75°, and long fibers are continued to be wound to form an angled winding layer. The winding tension of the long fibers is 20N. During angled winding, one forward winding and one reverse winding are performed at the same and symmetrical angle to form an angled winding layer. Then, the composite mesh layer is laid outside the angled winding layer and needle-punched. The needle-punching density is 15 needles / cm. 2 The acupuncture speed is 200 times / min.

[0055] (III) Intermediate Layer Preparation: Continue laying the bottom angled winding layer with a winding tension of 20N. Alternately lay the composite mesh layer and the angled winding layer to form a stacked structure of angled winding layer-mesh layer-angled winding layer-mesh layer. Needle punching and hooking are carried out simultaneously. Needle punching and hooking can be done immediately after each layer of composite mesh layer is laid, or it can be completed in a concentrated manner after laying multiple layers of composite mesh layer. The needle punching density is 15 needles / cm. 2 The acupuncture speed is 200 times / min.

[0056] (IV) Precast Forming: The intermediate layer is prepared in a cyclical and repeated manner, totaling 16 layers of angled winding layers and 16 layers of mesh layer. The winding angles from the inside out are 75°, 75°, 60°, 60°, 60°, 45°, 30°, 45°, 30°, 45°, 30°, 45°, 30°, 45°, 30°, 60°, 75°, and 75° (each angle is symmetrically wound on both sides as a group) until the laid thickness reaches the preset thickness. Finally, a circumferential winding layer and a composite mesh layer are laid, and needle-punched and hooked for fixation. The circumferential winding angle is 90°, the winding tension is 20N, and the needle-punching density is 15 needles / cm. 2 The needle puncture speed is 200 times / min to complete the laying of the precast body.

[0057] (v) Machining: Cut and demold to obtain the prefabricated semi-finished product of the required shape.

[0058] (vi) Gradient high temperature treatment: Under a protective atmosphere, the preform semi-finished product is heated to 200℃ at a rate of 2℃ / min and cured for 3h; then heated to 500℃ at a rate of 8℃ / min and kept at that temperature for 1h to complete the high temperature treatment and obtain the preform finished product.

[0059] The preform semi-finished product obtained in this embodiment has a tensile strength of 5 MPa, a T-peel strength of 10 N / mm, and an interlaminar shear strength of 10 MPa after high-temperature treatment.

[0060] Example 4: The difference between this example and Example 2 is that there is no angled winding layer in the intermediate layer preparation process. That is, the intermediate layer preparation process uses carbon cloth + mesh + circumferential + mesh + needle punching, repeating this step until 15 mesh layers are completed. Other process parameters are the same as in Example 2. The preform semi-finished product obtained in this example has a tensile strength of 5 MPa and a T-peel strength of 2.8 N / mm. The interlaminar shear strength of the preform finished product after high-temperature treatment is 5 MPa.

[0061] Example 5: This example uses a composite mesh to prepare a precast panel. The processing method for this precast panel specifically includes the following steps: Short fibers were obtained by shaving T700 carbon fiber precursor and then processed into a carbon fiber chopped web. The single-layer basis weight of the web was 120 g / m². 2The mesh fabric is fed into an impregnation and extrusion device, undergoing impregnation with liquid resin, impregnation and extrusion, and then further impregnation with liquid resin. The liquid resin is a composite resin system, obtained by mixing phenolic resin and polysilazane at a mass ratio of 4:6, and its viscosity is adjusted to 200 mPa·s at 25°C. The impregnation time is 5 min, and the fabric is squeezed dry and weighed to obtain a resin-containing mesh fabric with a basis weight of 576 g / m². A carbon nanotube dispersion is then sprayed onto the surface of the resin-containing mesh fabric. The carbon nanotube dispersion has a viscosity of 22 mPa·s, an outer diameter of 10-20 nm, a length of 20-50 μm, a solid content of 5 wt%, and a spraying density of 3 g / m². 2 This forms a composite mesh tire.

[0062] A surface density of 400 g / m³ was selected. 2 Carbon fiber cloth was used as the in-plane reinforcement material. The composite mesh and carbon fiber cloth were alternately laid and needle-punched at a needle-punching density of 8 needles / cm. 2 To enhance the Z-axis connection between layers, composite mesh is placed between adjacent carbon cloth layers, and the above-mentioned layering and needle punching process is repeated to form a multi-layer composite prefabricated panel.

[0063] The preform of the board obtained in this embodiment is placed in a flat mold for hot pressing and curing at a temperature of 180°C, a pressure of 4 MPa, and a time of 2 hours to obtain a cured board. Subsequently, the cured board semi-finished product is placed in an inert atmosphere and carbonized at 950°C to obtain the finished board.

[0064] The obtained board was subjected to performance tests, and no obvious delamination or blistering defects were observed inside the board; the interlaminar shear strength of the board was 12 MPa.

[0065] Comparative Example 1: The difference between this example and Example 2 is that after obtaining the resin-containing mesh during the composite mesh preparation process, carbon nanotubes are not sprayed on. Other process parameters are the same as in Example 2. The preform semi-finished product obtained in this example has a tensile strength of 6 MPa, a T-peel strength of 3.6 N / mm, and an interlaminar shear strength of 8 MPa after high-temperature treatment. Comparing Example 2 and Comparative Example 1, it can be seen that spraying a carbon nanotube dispersion after resin impregnation-extrusion-re-impregnation not only results in carbon nanotubes on the mesh surface, but also allows the carbon nanotubes on the composite mesh surface to be mechanically carried into the interlayer and internal pores of the mesh during the subsequent needle-punching process, forming a nanoscale bridging structure between fiber bundles, at interlayer interfaces, and in pore areas. This also facilitates the uniform discharge of volatiles during subsequent high-temperature treatment, thereby reducing the probability of internal defects. The resulting preform semi-finished product has a more uniform structure, reduced delamination and cracking tendency, and ultimately improved structural integrity and mechanical properties.

[0066] Comparative Example 2: The difference between this example and Example 2 is that in the preparation of the composite mesh, a conventional single-pass impregnation process without impregnation and extrusion is used. After impregnation, the material is squeezed dry and weighed to obtain a basis weight of 362 g / m². 2 The weight gain after impregnation was 262%, and other process parameters were the same as in Example 2. The preform semi-finished product obtained in this example had a tensile strength of 5.6 MPa, a T-peel strength of 3.5 N / mm, and an interlaminar shear strength of 7 MPa after high-temperature treatment. Example 2 and Comparative Example 2 were tested under the same dimensions and environmental conditions. It can be seen that the method of the present invention, with the first impregnation filling large pores, followed by impregnation and extrusion to release air and excess resin, and the second impregnation filling the gaps between micropores and fiber bundles, can increase the effective liquid resin content in the mesh by more than 100%. The resin distribution in the fiber bundles and pores is more uniform, thereby improving the density of the preform semi-finished product, reducing pore defects, and ultimately resulting in a preform finished product exhibiting superior mechanical properties and structural stability.

[0067] Comparative Example 3: The difference between this example and Example 2 is that, instead of gradient high-temperature treatment after machining, the preform semi-finished product is rapidly heated to 800°C at a rate of 10°C / min and held at that temperature. Other process parameters are the same as in Example 2. The preform semi-finished product obtained in this example has a tensile strength of 7 MPa, a T-peel strength of 4.5 N / mm, and an interlaminar shear strength of 8 MPa after high-temperature treatment. By comparing Example 2 and Comparative Example 3, it can be seen that the gradient high-temperature treatment process can achieve gradual curing and transformation of the resin, avoiding the violent release of internal gases caused by rapid heating, thereby reducing the generation of porosity and microcracks. In contrast, non-gradient high-temperature treatment easily causes structural stress concentration, increasing internal defects in the preform semi-finished product, and ultimately reducing the density and mechanical properties of the preform finished product.

[0068] Comparative Example 4: The difference between this example and Example 2 is that after obtaining the resin-containing mesh during the composite mesh preparation process, carbon nanotubes are not sprayed on, and gradient high-temperature treatment is not performed after machining. Instead, the preform semi-finished product is rapidly heated to 800°C at a rate of 10°C / min and held at that temperature. Other process parameters are the same as in Example 2. The tensile strength of the preform semi-finished product obtained in this example is 6 MPa, the T-peel strength is 2.5 N / mm, and the interlaminar shear strength of the preform finished product after high-temperature treatment is 2 MPa. Further comparison shows that when neither carbon nanotube dispersion is sprayed on nor gradient high-temperature treatment is used, the preform semi-finished product is more prone to internal gas retention and stress concentration during heat treatment, leading to increased porosity and structural defects. However, this invention, through the synergistic effect of spraying carbon nanotube dispersion and gradient high-temperature treatment, can effectively improve the venting path and release thermal stress, thereby significantly improving the density, structural uniformity, and overall performance of the preform finished product.

[0069] Comparative Example 5: Unlike Example 5, this example uses a conventional single-pass, non-impregnation-extrusion impregnation process and does not spray carbon nanotube dispersion onto the mesh surface. The resulting carbonized sheet was tested, and the results showed that localized interlayer bulging occurred, indicating unsatisfactory bonding; the interlayer shear strength was 7 MPa. Comparing Example 5 and Comparative Example 5 demonstrates that using the composite mesh of this invention as the interlayer structure is beneficial for improving the interlayer bonding performance of the sheet.

[0070] In summary, when the composite mesh of the present invention is used as an interlayer structural material, it can play a role in connection, buffering and structural transition during the subsequent product molding process, which is beneficial to improving the stability of interlayer bonding. The composite mesh preparation method of the present invention is simple, has good repeatability, and is suitable for industrial promotion and application.

[0071] By creatively introducing a resin impregnation-extrusion-re-impregnation liquid resin process, the liquid resin content in the mesh is increased (by more than double) and its uniformity is improved, effectively reducing the delamination phenomenon caused by uneven resin distribution. The preform semi-finished product undergoes gradient high-temperature treatment. During the high-temperature heating process, the resin (such as phenolic resin, epoxy resin, etc.) in the carbon fiber preform undergoes a pyrolysis reaction, which decomposes to generate a large number of small molecule gases (such as H2, CH4, CO, CO2, H2O, etc.). If the gas diffusion channels (pores, fiber gaps) inside the preform are not unobstructed, the small molecule gases will not be able to escape in time, and the gas pressure trapped between layers or inside the preform will rise sharply. When the interlayer gas pressure exceeds the bonding force between layers (the strength of the resin matrix itself and the strength of the fiber / resin interface), it will "spread" the adjacent layers, resulting in delamination. Therefore, carbon nanotubes are introduced into the mesh. The carbon nanotubes are carried into the interior of the mesh during the needle punching process and form a through-hole multi-scale pore channel in the fiber gap during the subsequent heat treatment process, providing a channel for gas to escape and avoiding pressure accumulation that causes delamination.

[0072] The preform winding method of this invention replaces the traditional axial winding and carbon fiber reinforcement layer by forming a continuous long fiber structure using winding layers with different winding angles. This is equivalent to directly weaving a multi-directional fabric structure onto the mesh. When subjected to external force, the angled winding layers decompose the oblique force into axial and circumferential forces, replacing the carbon fiber reinforcement layer and axial fibers to provide reinforcement, thereby improving the preform structure strength and effectively reducing delamination. During high-temperature treatment, excessively rapid heating rates accelerate the pyrolysis reaction rate of the resin, leading to a dramatic increase in the amount of gas produced per unit time, greatly increasing the possibility of gas accumulation due to failure to dissipate in time. Simultaneously, rapid heating also exacerbates thermal stress, causing product delamination. By using a graded high-temperature treatment process to control the gas release rate, the risk of delamination can be reduced.

[0073] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a composite mesh tire, characterized in that, The specific preparation steps are as follows: the short fiber mesh is impregnated with liquid resin through an impregnation and extrusion device to form a resin-containing mesh; carbon nanotube dispersion is sprayed onto the surface of the resin-containing mesh to form a composite mesh.

2. The method for preparing the composite mesh tire according to claim 1, characterized in that, The short fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber; the liquid resin is one or more combinations of polysilazane, polycarbosilane, epoxy resin, phenolic resin, and urea-formaldehyde resin; the carbon nanotube dispersion has a liquid-to-solid content of 2-8%, a carbon nanotube length of 20-100 μm, a carbon nanotube outer diameter of 10-80 nm, and a spraying density of 1.0-5.0 g / m³. 2 .

3. The method for preparing the composite mesh tire according to claim 1, characterized in that, The impregnation and extrusion device includes an impregnation frame (1), an impregnation tank (2), a power drive mechanism (4), a tensioning mechanism (7), a guide roller assembly (9), a pressure roller assembly (10), an idler roller assembly (11), a pressure roller lifting adjustment mechanism (12), an idler roller lifting adjustment mechanism (13), a guide roller lifting adjustment mechanism (14), and a support member (21). The impregnation tank (2) is correspondingly located at the bottom of the inner side of the impregnation frame (1), and is used to contain liquid resin; The pressure roller assembly (10) and the idler roller assembly (11) are arranged on the impregnation frame along the traveling direction of the tire and are located above the impregnation tank (2); the pressure roller lifting adjustment mechanism (12) includes two sets that are driven to both ends of the pressure roller assembly (10) and are correspondingly arranged at both ends of the impregnation frame (1), for driving the pressure roller assembly (10) to move vertically to adjust the gap between it and the idler roller assembly (11); the idler roller lifting adjustment mechanism (13) includes two sets that are driven to both ends of the idler roller assembly (11) and are correspondingly arranged at both ends of the impregnation frame (1), for driving the idler roller assembly (11) to move vertically to adjust the gap between it and the pressure roller assembly (10); The guide roller assembly (9) is correspondingly disposed at the feed end of the idler roller assembly (11) and located above the impregnation tank (2), with its two ends respectively connected to the impregnation frame; the support member (21) is parallelly disposed below the guide roller assembly (9), and a gap is formed between the support member (21) and the guide roller assembly (9) for the mesh to pass through; the guide roller lifting adjustment mechanism (14) includes two sets of transmission connected to both ends of the guide roller assembly (9) and correspondingly disposed at both ends of the impregnation frame (1), used to drive the guide roller assembly (9) to move vertically, so as to adjust the distance between the guide roller assembly (9) and the support member (21); The power drive mechanism (4) is connected to the pressure roller assembly (10), the idler roller assembly (11), and the guide roller assembly (9) via the tensioning mechanism (7) and is used to drive the pressure roller assembly (10), the idler roller assembly (11), and the guide roller assembly (9) to rotate so as to continuously traction the tire.

4. The method for preparing the composite mesh tire according to claim 3, characterized in that, The pressure roller assembly (10), the idler roller assembly (11) and the guide roller assembly (9) all include a roller body and corresponding support shafts at both ends of the roller body, and a transmission sprocket (18) is connected to the support shaft end on the same side of the pressure roller assembly (10), the idler roller assembly (11) and the guide roller assembly (9).

5. The method for preparing the composite mesh tire according to claim 4, characterized in that, The two ends of the immersion frame (1) are respectively provided with side baffles (16) on the upper side of the immersion tank (2). Each side baffle (16) has two guide grooves (17) longitudinally parallel along its width direction, and the guide grooves (17) of the two side baffles (16) are correspondingly provided. The pressure roller lifting adjustment mechanism (12), the idler roller lifting adjustment mechanism (13), and the guide roller lifting adjustment mechanism (14) all include a slider bearing that is slidably connected in the guide groove (17) and an adjustment screw that is provided along the direction of the guide groove (17). One end of the adjustment screw is rotatably connected to the side wall of the slider bearing, and the other end of the adjustment screw is threadedly connected to the impregnation frame (1). Rotating the adjustment screw can drive the slider bearing to move vertically along the guide groove (17), thereby driving the pressure roller assembly (10), the idler roller assembly (11), and the guide roller assembly (9) to adjust their lifting positions.

6. The method for preparing the composite mesh tire according to claim 5, characterized in that, The tensioning mechanism (7) includes a tensioning bracket (71), a U-shaped seat (72), a tensioning sprocket (73), and a tensioning screw (74). The tensioning bracket (71) and the power drive mechanism (4) are fixed to one end of the immersion frame (1). The U-shaped seat (72) is connected to the tensioning bracket (71) through the tensioning screw (74). The tensioning sprocket (73) is rotatably installed inside the U-shaped seat (72). By rotating the tensioning screw (74), the U-shaped seat (72) can be driven to slide back and forth along the tensioning bracket (71).

7. The method for preparing the composite mesh tire according to claim 6, characterized in that, The power drive mechanism (4) includes a drive motor and a matching gearbox. The drive shaft end of the gearbox is connected to a drive sprocket (5). The drive sprocket (5) is connected to each drive sprocket (18) and tension sprocket (73) via a transmission chain (6). After the drive motor starts, it can drive the guide roller assembly (9), pressure roller assembly (10) and idler roller assembly (11) to rotate synchronously via the sprocket chain transmission.

8. The method for preparing the composite mesh tire according to claim 3, characterized in that, The support member (21) may be a support plate or a support roller; the bottom of the impregnation tank (2) is provided with a discharge valve (15) for discharging the residual liquid resin in the tank; and the bottom four corners of the impregnation frame (1) are respectively provided with casters (8).

9. The application of the composite mesh tire as described in claim 1 in a wound preform, characterized in that, The application includes the following steps: Step S1, Base layer preparation: The composite mesh is laid outside the processing mold to form a mesh layer. Long fibers are wound around the mesh layer in the circumferential direction along the processing mold to form a circumferential winding layer. The winding angle is adjusted, and the long fibers are wound to form an angle winding layer. During angle winding, one forward winding and one reverse winding are performed at the same and symmetrical angle to form an angle winding layer. Then, the composite mesh layer is laid outside the angle winding layer and needle-punched and hooked. Finally, n layers (n≤1) of circumferential winding layers are laid. Step S2, intermediate layer preparation: continue to alternately lay angled winding layers and composite mesh layers to form an angled winding layer-composite mesh layer-angled winding layer-composite mesh layer structure; after the composite mesh layer is laid, needle punching is performed. The needle punching is performed after laying a single layer of mesh or after laying multiple layers of mesh. Step S3, Precast body forming: Repeat step S2 until the laying thickness reaches the preset thickness, and finally lay a circumferential winding layer and a composite mesh layer, and perform needle-punching and hooking fixation. Step S4, machining: cut and demold to obtain the preform semi-finished product of the required shape; Step S5, gradient high temperature treatment: Under a protective atmosphere, the preform semi-finished product is heated to 200-350℃ at a rate of 1-3℃ / min and held for 3-10h; then heated to 500-1000℃ at a rate of 5-10℃ / min and held for 1-5h to complete the high temperature treatment and obtain the preform finished product. In steps S1-S3, the long fibers are one or more combinations of carbon fiber, ceramic fiber, and quartz fiber; the circumferential winding angle is 90° and the winding tension is 10-20N; the angled winding angle is 15°-75° and the winding tension is 10-20N; the needle punching density is 15-35 needles / cm. 2 The acupuncture speed is 100-200 times / min.

10. The application of the composite mesh as described in claim 1 in precast slabs, characterized in that, The application includes the following steps: alternately laying and needle-punching composite mesh and carbon cloth, with the composite mesh placed between adjacent carbon cloth layers, and repeating the above laying and needle-punching process to form a multi-layer composite prefabricated panel.

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