Conductive strengthening process and equipment for fiber material / fiber product

Abstract

The invention discloses a conductive strengthening process and conductive strengthening equipment for a fiber material / fiber product, and belongs to the technical field of advanced manufacturing and material engineering. The invention provides an integrated solution special for conductive reinforcement of a fiber material / fiber product, and the growth of a carbon-based functional layer in the fiber material / fiber product is realized under a mild condition, so that a structure-function integrated composite material with bearing capacity and advanced functions is obtained; and the corresponding process and equipment not only can be used for treating discrete sheet-shaped workpieces, but also can be used for treating continuous coiled materials, so that the process applicability is good.

Description

Technical Field

[0001] This invention belongs to the field of advanced manufacturing and materials engineering technology, specifically relating to a conductive strengthening process and equipment for fiber materials / fiber products. Background Technology

[0002] With the rapid development of aerospace, intelligent equipment, new energy, and flexible electronics, the requirements for composite materials have shifted from simple structural load-bearing to "structure-function integration." While traditional structural materials (such as glass fiber, aramid fiber, and basalt fiber) possess excellent mechanical properties, their inherent limitations in insulation and other functions severely restrict their application in lightweight electromagnetic shielding, structural health monitoring, adaptive intelligent structures, and advanced protection. Therefore, enhancing the conductivity of fiber structural materials to prepare integrated composite materials with high strength, high modulus, and excellent electrical properties has become a key technological path to overcome the performance bottlenecks of next-generation high-end equipment and devices.

[0003] Currently, the main methods for strengthening the conductivity of fiber-reinforced materials are surface coating (such as coating with conductive polymers or carbon nanotube slurries) and electroless metal plating (such as silver or nickel plating). However, these methods have the following limitations: the conductive coatings constructed by surface coating or slurry impregnation methods have poor uniformity, which seriously affects the conductivity stability; electroless metal plating processes often involve complex pretreatment steps and the use of environmentally polluting chemicals, and the resulting conductive metal coatings have high density, making them prone to cracking and peeling due to the mismatch between the thermal expansion coefficients of the substrate and the coating. In contrast, the method of in-situ growth of carbon-based materials (such as graphene and carbon nanotubes) can obtain a conductive layer with strong adhesion, good uniformity, and significant lightweight advantages. Currently, the common method is to grow carbon-based functional layers through chemical vapor deposition (Adv. Funct. Mater. 2024, 34, 2409379; CN115613162A; CN118782296A, etc.). However, the above methods have stringent requirements for the high temperature resistance of fiber structural materials (they need to withstand temperatures above 800 ℃), poor process compatibility, and the corresponding processes have extremely high requirements for equipment, high energy consumption, and are difficult to apply to large-size components.

[0004] The existing technical approaches mentioned above struggle to balance universality, mild operating conditions, and functional layer stability. Therefore, there is an urgent need to develop a highly universal conductive functionalization process for fiber structural materials, along with its supporting equipment system. This would allow for the efficient construction of conductive interfaces under mild conditions, enhancing the conductivity of fiber structural materials while simultaneously ensuring good environmental stability of the functional layers. Ultimately, this would provide a reliable material foundation for the design and manufacturing of high-performance integrated structural and functional components, and promote their engineering applications. Summary of the Invention

[0005] To address the shortcomings of the existing technologies, this invention provides a conductive strengthening process and equipment for fiber materials / fiber products. The process is simple and widely applicable. Conductive strengthening is achieved by growing a carbon-based functional layer in the fiber material / fiber product under mild conditions, resulting in a "structure-function integrated" composite material that combines load-bearing capacity and advanced functions.

[0006] The specific technical solution adopted is as follows: A conductive strengthening process for fiber materials / fiber products includes the following steps: S01 Flatten and tension the fiber material / fiber product to be reinforced; S02 Coating the surface of the tensioned fiber material / fiber product with a liquid precursor, followed by heating and impregnation; the liquid precursor is a eutectic mixture, benzoxazine compound or oligomer of the corresponding benzoxazine compound, and the heating and impregnation conditions are a temperature of 40~120 ℃ and a time of 2~10 min. SO3 is used to treat the fiber material / fiber product after SO2 treatment by laser irradiation at room temperature to convert the liquid precursor into carbon material to build a conductive path. Then, it is heated in an inert atmosphere for high-temperature purification and strengthening. The conditions for high-temperature purification and strengthening are 300~650 ℃ and 1~30 min. After cooling, the conductive strengthening is completed.

[0007] In S01, the fiber materials include, but are not limited to, glass fiber, aluminum silicate fiber, basalt fiber, quartz fiber, Kevlar fiber or carbon fiber, etc., and the fiber products include, but are not limited to, glass fiber products, aluminum silicate fiber products, basalt fiber products, quartz fiber products, Kevlar fiber products or carbon fiber products, etc.

[0008] Optionally, when the fiber material / fiber product to be reinforced is a roll material, the roll material is unwound and flattened to achieve the flattening of the roll material.

[0009] In SO2, the eutectic mixture includes hydrogen bond donors, hydrogen bond acceptors, and carbon source organics; hydrogen bond donors include any one or more combinations of amide compounds, alcohols, phenolic compounds, inorganic acids, organic acids, and water; hydrogen bond acceptors include any one or more combinations of choline compounds, alcohols, organic acids, metal salts, ether compounds, carbonyl compounds, ester compounds, and water; the carbon source organics have an aromatic ring structure and are selected from tannic acid, ellagic acid, daidzein, hesperidin, propyl gallate, 3,3′,4,4′ biphenyltetracarboxylic dianhydride, bisphenol A, 2,7-diaminofluorene, fulvic acid, 1-naphthoic acid, etc.

[0010] Furthermore, the eutectic mixture may also include dopants, which include any one or more combinations of metal nanoparticles, metal oxide nanoparticles, metal carbide nanoparticles, metal salts, organometallic compounds, MXene, graphene and its derivatives, carbon nanotubes, carbon black, carbon fibers, carbon nanofibers, zeolites, nitrides, borides, phosphides, sulfides, and fluorides.

[0011] In SO2, the structural formula of benzoxazine compounds is shown in formula (I): ; Formula (I); Wherein, R1 is selected from substituted or unsubstituted phenyl, furfuryl or naphthyl; R2 is selected from substituted or unsubstituted alkyl, alkoxy, phenyl or naphthyl.

[0012] The liquid precursor needs to penetrate into the fiber material / product to be strengthened before laser irradiation to achieve sufficient contact. However, excessively high viscosity hinders rapid penetration within the material. Conversely, excessively low viscosity can lead to uncontrolled diffusion, affecting the quality of the subsequent laser-strengthened carbon material. By controlling the heating temperature and time, the viscosity and percolation behavior of the liquid precursor can be adjusted and optimized, ensuring rapid and effective wetting of the surface of the fiber material / product.

[0013] Preferably, in S03, during laser irradiation enhancement, the laser output wavelength is 266 nm to 10.6 μm, the laser power is 3 to 35 W, and the defocusing distance is 0 to 5 mm.

[0014] Preferably, the inert atmosphere during high-temperature purification and strengthening is argon. During the high-temperature purification and strengthening process, the remaining uncarbonized or partially carbonized liquid precursors are fully pyrolyzed and completely carbonized at high temperatures, enhancing the structural stability of the material under high-temperature operating conditions. Simultaneously, the high temperature acts as an annealing optimization for the laser-generated carbon material in situ, thereby further improving the material's electrical conductivity.

[0015] The present invention also provides a conductive strengthening device for fiber materials / fiber products, including a transmission system, a liquid precursor control module, a heating module, a laser in-situ strengthening module, and a high-temperature purification strengthening module; The transmission system is used to transfer the target fiber material / fiber product to be reinforced between modules; The liquid precursor control module includes a dispensing system and a vision system. The dispensing system is used to coat the liquid precursor onto the surface of the target fiber material / fiber product to be reinforced, and the vision system is used to monitor the coating position and status of the liquid precursor in real time. The heating module is used to control the wetting process of the liquid precursor coated on the surface of the target fiber material / fiber product to be reinforced; The laser in-situ strengthening module includes a laser system, which emits a laser beam to the target fiber material / fiber product to be strengthened that is impregnated with a liquid precursor, so that the liquid precursor is converted into a carbon material to build a conductive path, and the workpiece is obtained after laser in-situ strengthening. The high-temperature purification and strengthening module is used to perform high-temperature heat treatment strengthening on workpieces that have been laser-strengthened in situ in an inert atmosphere.

[0016] The conductive strengthening equipment for fiber materials / fiber products also includes a central control system, which is connected to the transmission system, liquid precursor control module, heating module, laser in-situ strengthening module, and high-temperature purification strengthening module to coordinate and control the conductive strengthening process of fiber materials / fiber products.

[0017] The transmission system includes a servo motor driven conveying mechanism, a stripping mechanism for separating the laser-strengthened workpiece from the conveying mechanism, and a feeding uncoiler, a discharging rewinder, and a flattening mechanism for processing rolled materials.

[0018] Specifically, the dispensing system includes a dispensing valve and a feeding device. The dispensing valve is used to quantitatively coat the surface of the target fiber material / fiber product with liquid precursor. The feeding device is used to store the liquid precursor. The dispensing valve is one of a precision screw dispensing valve, a pneumatic dispensing valve, or a piezoelectric jet valve. The dispensing valve is connected to the feeding device through a pipeline. The dispensing valve, the feeding device, and the connecting pipeline are all equipped with independent heating devices to control the flowability of the liquid precursor.

[0019] Furthermore, the dispensing valve is mounted on a robotic arm or a precision lead screw linear module, which is used to drive the dispensing valve to move in three-dimensional or two-dimensional directions.

[0020] Specifically, the vision system includes an industrial camera and lens, which are mounted near the dispensing valve via a mounting bracket to monitor the coating position and status of the liquid solder in real time. The industrial camera is equipped with a light source and an image processing unit to ensure accurate coating of the liquid precursor.

[0021] Specifically, the laser in-situ enhancement module is also equipped with a dust removal device, which includes a dust hood and a smoke purifier. The opening end of the dust hood faces the laser irradiation area, and the other end is connected to the smoke purifier through a pipe to absorb and purify the smoke and particulate matter generated during the laser irradiation carbonization process.

[0022] Specifically, the high-temperature purification enhancement module includes a high-temperature treatment furnace, which is a box furnace that uses the Joule heating principle and has an inert atmosphere inside. The high-temperature treatment furnace has a built-in transmission roller conveyor device.

[0023] Furthermore, the high-temperature purification enhancement module also includes an atmosphere protection device.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The process of the present invention provides an integrated solution for conductive strengthening of fiber materials / fiber products through a multi-module collaborative process of "liquid precursor coating - laser in-situ strengthening - high temperature purification strengthening". By achieving the growth of carbon-based functional layers in fiber materials / fiber products under mild conditions, a "structure-function integrated" composite material with both load-bearing capacity and advanced functions is obtained.

[0025] (2) The conductive strengthening process and equipment provided by this invention have the ability to process both continuous roll-shaped structural materials (such as glass fiber, basalt fiber, Kevlar fiber, etc.) and discrete sheet-shaped structural workpieces. Through modular design, it meets the production needs of different shapes and batches. Moreover, the corresponding strengthening process conditions (performed at room temperature) are much lower than the harsh conditions required by traditional strengthening (above 800 ℃, inert atmosphere), which has a wider range of applications, lower energy consumption, milder equipment requirements, and makes it easier to realize the industrial continuous production of large-size components. Attached Figure Description

[0026] Figure 1 A schematic diagram of a carrier plate and the target fiber material / fiber product to be reinforced fixed on it.

[0027] Figure 2 This is a three-dimensional structural diagram of a conductive strengthening device for fiber materials / fiber products in the first direction.

[0028] Figure 3 This is a three-dimensional structural diagram of a conductive strengthening device for fiber materials / fiber products in the second direction.

[0029] Figure 4 This is a schematic diagram of the laser in-situ strengthening module.

[0030] Figure 5 This is a schematic diagram of the transmission system.

[0031] Figure 6 This is a schematic diagram of the stripping mechanism.

[0032] Figure 7 This is a schematic diagram of the external structure of the high-temperature purification enhancement module.

[0033] Figure 8 This is a schematic diagram of the internal structure of the high-temperature purification enhancement module.

[0034] Figure 9 This is a diagram illustrating the conductive strengthening effect of glass fiber.

[0035] Figure 10 This is a diagram illustrating the conductive reinforcement effect of Kevlar fibers.

[0036] Figure 11 This is a diagram illustrating the conductive strengthening effect of basalt fibers.

[0037] Reference numerals: 01 Roll material; 02 Sheet material; 03 Metal carrier plate; 04 Clamping mechanism; 1 Frame; 2 Liquid precursor control module; 2a Robotic arm; 2b Dispensing valve; 2c Vision system; 2d Feeding device; 3 Heating module; 4 Laser in-situ strengthening module; 41 Gantry mechanism; 42 Laser system; 43 Screw drive module; 44 Dust hood; 5 High-temperature purification strengthening module; 51 Housing shell; 52 Sample inlet / outlet; 53 Air inlet; 54 Support; 55 Non-contact thermometer; 561 First drive roller; 562 Second drive roller; 571 First copper electrode; 572 Second copper electrode; 58 Graphite rod; 59 Insulation tank; 6a Feeding uncoiler; 6b First flattening mechanism; 6c Conveying mechanism; 6d Peeling mechanism; 6e Discharge rewinder; 611 612 Support foot; 613 Chain plate transmission device; 614 First drive motor; 615 First ring module; 616 Second ring module; 617 Top plate assembly; 618 Secondary positioning system; 629 Mounting bracket; 620 Second flattening mechanism; 621 Third flattening mechanism; 622 Pressing mechanism; 623 Pressing mechanism; 624 Pressing mechanism; 625 Upper pressing mechanism; 626 Lower pressing mechanism; 627 Second drive motor. Detailed Implementation

[0038] To make the objectives, features, and advantages of this invention more apparent and understandable, a detailed description is provided below through specific embodiments. Many specific details are set forth in the following description to provide a thorough understanding of the invention. However, the invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below. Technical features in various embodiments of the invention can be combined appropriately without mutual conflict.

[0039] Unless otherwise specified, the operating methods in the following examples are generally performed under conventional conditions or as recommended by the manufacturer. Contents not described in detail in this specification are prior art known to those skilled in the art. Unless otherwise specified, the experimental materials used in the examples below can be purchased from conventional biochemical reagent companies.

[0040] Example 1 This embodiment provides a conductive strengthening device for fiber materials / fiber products, used to improve the conductivity of target fiber materials / fiber products (including rolled material 01 or sheet material 02), such as... Figure 1 As shown, for sheet materials, the sheet material 02 is fixed onto the metal carrier plate 03 by the clamping mechanism 04 to obtain the workpiece to be processed; specifically as follows... Figure 1 As shown, a schematic diagram of the conductive strengthening device for fiber materials / fiber products and its internal structure is as follows. Figures 2-8 As shown.

[0041] The conductive strengthening device includes a frame 1, and a liquid precursor control module 2, a heating module 3, a laser in-situ strengthening module 4, and a high-temperature purification strengthening module 5 are arranged sequentially along the workpiece processing flow direction. It also includes a transfer system for transferring workpieces between the modules.

[0042] The conductivity enhancement equipment also includes a central control system, which is connected to the transmission system, the liquid precursor control module 2, the heating module 3, the laser in-situ enhancement module 4, and the high-temperature purification enhancement module 5 for signal coordination and control of the conductivity enhancement process.

[0043] The liquid precursor control module 2 includes a dispensing system and a vision system. The dispensing system is used to coat the liquid precursor onto the surface of the target fiber material / fiber product to be reinforced, and the vision system is used to monitor the coating position and status of the liquid precursor in real time. The dispensing system includes a dispensing valve 2b and a feeding device 2d. The dispensing valve 2b is used to quantitatively coat the liquid precursor onto the surface of the target fiber material / fiber product to be reinforced, and the dispensing valve 2b is connected to the feeding device 2d through a pipe. The dispensing valve 2b is mounted on a multi-axis robotic arm 2a, which drives the dispensing valve 2b to move in three-dimensional or two-dimensional directions. A vision system 2c is integrated at the end of the robotic arm 2a, which is used to monitor the coating position and status of the liquid precursor in real time. The vision system 2c feeds back the coating status to the central control system, which then sends a command to the robotic arm 2a to load the dispensing valve 2b for additional glue application.

[0044] Heating module 3 is used to control the wetting process of the liquid precursor coated on the workpiece surface.

[0045] The laser in-situ strengthening module 4 includes a gantry mechanism 41 and a laser system 42. It emits a laser beam onto a workpiece impregnated with a liquid precursor, converting the liquid precursor into carbon material to construct a conductive path, thereby enhancing conductivity and obtaining a laser-strengthened workpiece. The gantry mechanism 41 is mounted on the frame 1, and the laser system 42 is installed on the gantry mechanism 41 via a screw drive module 43, which is used to adjust the focal length of the laser system 42. The laser system 42 contains seven lasers with wavelengths ranging from 266 nm to 10.6 μm. Each laser can operate independently or in multiple coordinated actions. The laser in-situ strengthening module 4 also includes a dust hood 44 located below the laser system 42. The dust hood 44 is mounted on the gantry mechanism 41 via a bracket. The opening of the dust hood 44 faces the laser irradiation area, and the other end is connected to a fume purifier via a pipe to absorb and purify the fumes and particulate matter generated during the laser irradiation carbonization process.

[0046] The high-temperature purification and strengthening module 5 is used to perform high-temperature heat treatment strengthening on laser-strengthened workpieces in an inert atmosphere. It includes a high-temperature treatment furnace, which is a box furnace using the Joule heating principle. The outer shell 51 of the box furnace has a workpiece inlet / outlet 52 and an inlet 53 for introducing inert gas. A bracket 54 is installed on the top of the outer shell 51, on which a non-contact thermometer 55 is mounted for real-time monitoring of the internal working temperature. Inside the box furnace, there are a first transmission roller 561 and a second transmission roller 562 for carrying and conveying the workpiece. The first and second drive rollers 562 are installed through the outer shell 51 of the box furnace. The box furnace also includes a first copper electrode 571, a second copper electrode 572 and a graphite rod 58. The first copper electrode 571 and the second copper electrode 572 are located at both ends of the heat preservation tank 59 and are connected to an external power source. The graphite rod 58 is sandwiched between the first copper electrode 571 and the second copper electrode 572 and is located inside the heat preservation tank 59. It generates high temperature through the Joule effect and constitutes the main heat source. The heat preservation tank 59 is made of high insulation and heat insulation material to reduce heat loss and maintain a uniform and stable thermal field.

[0047] The transmission system includes a conveying mechanism 6c for carrying and stepping the workpiece, and a peeling mechanism 6d for separating the laser-enhanced workpiece from the conveying mechanism 6. It also includes components for processing the roll material 01, specifically including a feeding uncoiler 6a, a first flattening mechanism 6b (for flattening the roll material), and a defecation rewinder 6e for winding the finished product. The feeding uncoiler 6a, the first flattening mechanism 6b, and the peeling mechanism 6d are located on the upper part of the frame 1, and the conveying mechanism 6c is located inside the frame 1. The first flattening mechanism 6b is close to the feeding uncoiler 6a, before the dispensing work area; the peeling mechanism 6d is before the high-temperature purification and strengthening module 5; and the defecation rewinder 6e is after the high-temperature purification and strengthening module 5.

[0048] The conveying mechanism 6c is a chain plate conveyor, including a supporting foot 611 and a chain plate conveying device 612 mounted on the supporting foot. The chain plate conveying device 612 includes a first ring module 614 and a second ring module 615 driven by a first drive motor 613, and a top plate assembly 616 mounted on the first ring module 614 and the second ring module 615 for carrying the workpiece. The conveying mechanism 6c is also equipped with a secondary positioning system 617 to achieve precise positioning of the workpiece.

[0049] The peeling mechanism 6d includes a mounting frame 621, and a second flattening mechanism 622, a third flattening mechanism 623, and a clamping mechanism 624 mounted on the mounting frame 621 for unwinding and guiding the roll. The clamping mechanism 624 is equipped with an upper clamping mechanism 625 for applying pressure. The upper clamping mechanism 625 includes a downward pressure bar driven by a screw module and a pressure control unit for detecting the applied pressure, which is used to peel the roll from the surface of the conveying mechanism 6c. The clamping mechanism 624 also includes a lower clamping mechanism 626 for pulling the roll. The lower clamping mechanism includes a lower clamping bar driven to rotate by a second drive motor 627. The clamping mechanism 624 is located between the second flattening mechanism 622 and the third flattening mechanism 623.

[0050] Specifically, the operational procedure for the conductive reinforcement process of fiber materials / fiber products is as follows: (1) Flatten and tension the fiber material / fiber product to be reinforced. For sheet materials, follow the instructions. Figure 1 The method of flattening and tensioning is as follows: For roll materials, the feeding uncoiler 6a and the first flattening mechanism 6b of the conductive strengthening equipment are used to flatten and tension the roll materials. Specifically, the roll materials are installed on the feeding uncoiler 6a, and the material head is pulled through the first flattening mechanism 6b in sequence to flatten and tension the roll materials. Under the control of the overall control system, the fiber materials / fiber products to be strengthened are transferred between the modules using the transmission system. (2) The liquid precursor is coated on the surface of the fiber material / fiber product to be reinforced after tensioning in the liquid precursor control module 2, and then heated and impregnated in the heating module 3; (3) In the laser in-situ strengthening module 4, the surface of the fiber material / fiber product coated with liquid precursor is irradiated with laser. During laser irradiation strengthening, the laser output wavelength is 266 nm~10.6 μm, the laser power is 3~35 W, and the defocusing distance is 0~5 mm, so that the liquid precursor is converted into carbon material, a continuous conductive path is constructed, and the conductivity is strengthened. The workpiece after laser in-situ strengthening is obtained by peeling with the peeling mechanism 6d. (4) The workpiece after laser in-situ strengthening is heated in the inert atmosphere of the high temperature purification and strengthening module 5 to carry out high temperature purification and strengthening. After cooling, the conductive strengthening is completed. The conditions for high temperature purification and strengthening are 300~650 ℃ and the processing time is 1~30 min. For roll materials, after completing the conductive strengthening, they will be fixed on the output winding machine 6e to obtain the roll conductive strengthening product.

[0051] Specifically, for coating with benzoxazine compounds Basalt fibers were in-situ strengthened using a 10.6 μm carbon dioxide laser. The laser power was set to 30 W and the defocusing distance to 0 mm. Further high-temperature purification and strengthening was performed at 650 ℃ for 1 min. After conductivity strengthening, the basalt fibers changed from electrical insulation to a conductivity of 1540 S / m. The conductivity strengthening parameters were changed, with the laser power set to 20 W and the defocusing distance to 2 mm. Further high-temperature purification and strengthening was performed at 650 ℃ for 1 min, with other parameters remaining unchanged. After conductivity strengthening, the basalt fibers changed from electrical insulation to a conductivity of 1624 S / m. The conductivity strengthening effect is shown in the figure below. Figure 11 As shown.

[0052] For coating with benzoxazine compounds Kevlar fibers were in-situ strengthened using a 9.3 μm carbon dioxide laser. The laser power was set to 3 W and the defocusing distance to 5 mm. Further high-temperature purification and strengthening was performed at 300 °C for 10 min. After conductive strengthening, the Kevlar fibers changed from electrical insulation to a conductivity of 589 S / m. The conductive strengthening parameters were changed again, with the laser power set to 5 W and the defocusing distance to 1 mm. Further high-temperature purification and strengthening was performed at 300 °C for 10 min, with other parameters remaining unchanged. After conductive strengthening, the Kevlar fibers changed from electrical insulation to a conductivity of 468 S / m. The conductive strengthening effect is shown in the figure below. Figure 10 As shown.

[0053] For glass fibers coated with a eutectic mixture (a mixture of choline chloride, urea, and tannic acid in a molar ratio of 1:2:0.8), in-situ strengthening was performed using a 266 nm ultraviolet laser with a laser power of 15 W and a defocusing distance of 3 mm. Further high-temperature purification strengthening was then performed at 500 °C for 30 min. After conductive strengthening, the glass fibers changed from being electrically insulating to having a conductivity of 1265 S / m. The conductive strengthening effect is shown in the figure below. Figure 9 As shown.

[0054] Quartz fibers coated with a eutectic mixture (a mixture of choline chloride, urea, and tannic acid in a molar ratio of 1:2:0.8) were in-situ strengthened using a 375 nm ultraviolet laser with a power of 12 W and a defocusing distance of 2 mm. Further high-temperature purification and strengthening were performed at 600 °C for 10 min. After conductive strengthening, the glass fibers changed from being electrically insulating to having a conductivity of 852 S / m.

[0055] For carbon fibers coated with a eutectic mixture (a mixture of choline chloride, urea, and daidzein in a molar ratio of 1:2:1), in-situ strengthening was performed using a 375 nm ultraviolet laser with a power of 9 W and a defocusing distance of 1.5 mm. Further high-temperature purification and strengthening were then carried out at 650 °C for 3 min. After conductivity strengthening, the conductivity of the carbon fibers increased by 1324 S / m (compared to 1218 S / m for the original carbon fibers).

[0056] The embodiments described above provide a detailed explanation of the technical solutions of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, additions, or similar substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A conductive strengthening process for fiber materials / fiber products, characterized in that, Includes the following steps: S01 Flatten and tension the fiber material / fiber product to be reinforced; S02 Coating the surface of the tensioned fiber material / fiber product with a liquid precursor, followed by heating and impregnation; the liquid precursor is a eutectic mixture, benzoxazine compound or oligomer of the corresponding benzoxazine compound, and the heating and impregnation conditions are a temperature of 40~120 ℃ and a time of 2~10 min. SO3 is used to treat the fiber material / fiber product after SO2 treatment by laser irradiation at room temperature to convert the liquid precursor into carbon material to build a conductive path. Then, it is heated in an inert atmosphere for high-temperature purification and strengthening. The conditions for high-temperature purification and strengthening are 300~650 ℃ and 1~30 min. After cooling, the conductive strengthening is completed.

2. The conductive strengthening process for fiber materials / fiber products according to claim 1, characterized in that, In S01, the fiber material includes glass fiber, aluminum silicate fiber, basalt fiber, quartz fiber, Kevlar fiber or carbon fiber, and the fiber product includes glass fiber product, aluminum silicate fiber product, basalt fiber product, quartz fiber product, Kevlar fiber product or carbon fiber product.

3. The conductive strengthening process for fiber materials / fiber products according to claim 1, characterized in that, In SO2, the eutectic mixture includes hydrogen bond donors, hydrogen bond acceptors, and carbon source organic matter; In SO2, the structural formula of benzoxazine compounds is shown in formula (I): ； Formula (I); Wherein, R1 is selected from substituted or unsubstituted phenyl, furfuryl or naphthyl; R2 is selected from substituted or unsubstituted alkyl, alkoxy, phenyl or naphthyl.

4. The conductive strengthening process for fiber materials / fiber products according to claim 1, characterized in that, In S03, during laser irradiation enhancement, the laser output wavelength is 266 nm to 10.6 μm, the laser power is 3 to 35 W, and the defocusing distance is 0 to 5 mm.

5. A conductive strengthening device for fiber materials / fiber products, characterized in that, It includes a transport system, a liquid precursor control module, a heating module, a laser in-situ enhancement module, and a high-temperature purification enhancement module; The transmission system is used to transfer the target fiber material / fiber product to be reinforced between modules; The liquid precursor control module includes a dispensing system and a vision system. The dispensing system is used to coat the liquid precursor onto the surface of the target fiber material / fiber product to be reinforced, and the vision system is used to monitor the coating position and status of the liquid precursor in real time. The heating module is used to control the wetting process of the liquid precursor coated on the surface of the target fiber material / fiber product to be reinforced; The laser in-situ strengthening module includes a laser system, which emits a laser beam to the target fiber material / fiber product to be strengthened that is impregnated with a liquid precursor, so that the liquid precursor is converted into a carbon material to build a conductive path, and the workpiece is obtained after laser in-situ strengthening. The high-temperature purification and strengthening module is used to perform high-temperature heat treatment strengthening on workpieces that have been laser-strengthened in situ in an inert atmosphere.

6. The conductive strengthening device for fiber materials / fiber products according to claim 5, characterized in that, The conductive strengthening equipment for fiber materials / fiber products also includes a central control system, which is connected to the transmission system, liquid precursor control module, heating module, laser in-situ strengthening module, and high-temperature purification strengthening module to coordinate and control the conductive strengthening process of fiber materials / fiber products.

7. The conductive strengthening device for fiber materials / fiber products according to claim 5, characterized in that, The transmission system includes a servo motor driven conveying mechanism, a stripping mechanism for separating the laser-strengthened workpiece from the conveying mechanism, and a feeding uncoiler, a discharging rewinder, and a flattening mechanism for processing rolled materials.

8. The conductive strengthening device for fiber materials / fiber products according to claim 5, characterized in that, The dispensing system includes a dispensing valve and a feeding device. The dispensing valve is used to quantitatively coat the surface of the target fiber material / fiber product with liquid precursor. The feeding device is used to store the liquid precursor. The dispensing valve is one of a precision screw dispensing valve, a pneumatic dispensing valve, or a piezoelectric jet valve. The dispensing valve is connected to the feeding device through a pipeline. The dispensing valve, the feeding device, and the connecting pipeline are all equipped with independent heating devices to control the flowability of the liquid precursor.

9. The conductive strengthening device for fiber materials / fiber products according to claim 5, characterized in that, The laser in-situ enhancement module is also equipped with a dust removal device, which includes a dust hood and a fume purifier. The opening end of the dust hood faces the laser irradiation area, and the other end is connected to the fume purifier through a pipe.

10. The conductive strengthening device for fiber materials / fiber products according to claim 5, characterized in that, The high-temperature purification enhancement module includes a high-temperature treatment furnace, which is a box furnace that uses the Joule heating principle and has an inert atmosphere inside.

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