Glass fiber bundling wheel based on graphite composite material and preparation method thereof

Abstract

The invention belongs to the technical field of glass fibers, and discloses a glass fiber bundling wheel based on a graphite composite material and a preparation method of the glass fiber bundling wheel. The bundling wheel is made of a composite material comprising the following components: 50%-70% of polytetrafluoroethylene, 10%-25% of crystalline flake graphite, 1%-5% of antimony, 3%-10% of carbon nanotubes, 2%-8% of nano titanium dioxide and 5%-15% of chopped glass fibers; the preparation method comprises the following steps: mixing polytetrafluoroethylene, crystalline flake graphite, antimony, carbon nanotubes, nano titanium dioxide and chopped glass fibers step by step according to a ratio to obtain a mixed material; quantitatively weighing the mixed material, putting into a mold, carrying out hot press molding on the material by gradient pressurization and temperature increase, and then carrying out depressurization cooling to obtain a molded product; and polishing the surface of the formed product, and performing heat treatment to obtain the bundling wheel. According to the glass fiber bundling wheel, the bending strength, the impact strength and the abrasive resistance are effectively improved, the friction coefficient is reduced, zero particle falling can be achieved, the service life and the maintenance period are prolonged, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of glass fibers, and in particular to a glass fiber bundling wheel based on graphite composite materials and a preparation method thereof. Background Art

[0002] The glass fiber bunching wheel is a key component in glass fiber drawing production lines and is widely used in the production of various types of glass fibers, including electronic-grade glass fiber and industrial-grade glass fiber. It is primarily used to gather the glass fibers flowing from the nozzle of the bushing plate, forming the dispersed fibers into a bundle for subsequent processing.

[0003] Existing glass fiber clustering wheels are mostly made of pure graphite, offering advantages such as high strength, excellent thermal shock resistance, high temperature resistance, corrosion resistance, low impurity content, and excellent self-lubrication. However, their low hardness and susceptibility to wear lead to rapid wear, a short service life, and high consumption, which in turn increases production costs. Worn clustering wheels are prone to shedding tiny particles, which can mix with the glass fiber, contaminating the product and posing quality risks. Worn clustering wheels require frequent replacement, requiring regular downtime and reducing production efficiency.

[0004] Therefore, there is an urgent need for a new composite material that has high wear resistance, low friction coefficient and no particle shedding. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a glass fiber bundling wheel based on graphite composite material and a preparation method thereof.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions: a glass fiber bundling wheel based on graphite composite material, made of a composite material including the following components in mass fractions: 50%-70% polytetrafluoroethylene, 10%-25% flake graphite, 1%-5% antimony, 3%-10% carbon nanotubes, 2%-8% nano-titanium dioxide, and 5%-15% chopped glass fiber.

[0007] A method for preparing a glass fiber cluster wheel based on graphite composite material comprises the following steps:

[0008] Step 1: Mixing in steps: polytetrafluoroethylene, flake graphite, antimony, carbon nanotubes, nano-titanium dioxide, and chopped glass fibers in proportion by mass to obtain a mixed material;

[0009] Step 2: Gradient hot pressing molding, quantitatively weighing the above mixed material and placing it in a preheated mold, gradiently increasing pressure and temperature to hot press the mixed material in the mold, and then reducing pressure and cooling to obtain a molded product;

[0010] Step 3: Post-processing: first polish the surface of the molded product, and then perform heat treatment to obtain a graphite composite material cluster wheel product.

[0011] Furthermore, the step 1 further includes the following steps:

[0012] Step 1.1: premixing polytetrafluoroethylene, nano-titanium dioxide, and carbon nanotubes to obtain a polytetrafluoroethylene matrix premix;

[0013] Step 1.2: dispersing flake graphite and antimony to obtain a graphite-antimony composite dispersion slurry;

[0014] Step 1.3: Preliminarily mix the polytetrafluoroethylene matrix premix and the graphite-antimony composite dispersion slurry, then add equal amounts of chopped glass fibers in batches and stir and mix to prepare a mixed material.

[0015] Furthermore, the step 1.1 further includes the following steps:

[0016] Step 1.1.1: Prepare a 5%-8% carbon nanotube suspension in ethanol;

[0017] Step 1.1.2: Add polytetrafluoroethylene powder preheated in a hot air circulation drying oven to the cavity of the three-dimensional motion mixer. Then, add equal amounts of nano-titanium dioxide in batches. Then, spray the ethanol suspension through the atomizing nozzle at a steady flow rate of 2-5 mL / min.

[0018] Step 1.1.3: Start the three-dimensional motion mixer and mix in a forward and reverse alternating operation mode, switching the direction every 10-15 minutes, mixing for 45-65 minutes, and mixing at a temperature of 25-35° C. to obtain a polytetrafluoroethylene matrix premix.

[0019] Furthermore, the step 1.2 further includes the following steps:

[0020] Step 1.2.1: Mix the silane coupling agent and anhydrous ethanol under a magnetic stirrer to prepare a pretreatment dispersion;

[0021] Step 1.2.2: Add flake graphite to the pre-treated dispersion;

[0022] Step 1.2.3: Place the container containing the pretreated dispersion containing flake graphite in a constant temperature water bath at 55±2°C and start the ultrasonic cell disruptor for dispersion for 40-60 minutes;

[0023] Step 1.2.4: Add dried antimony powder and continue ultrasonic dispersion for 15-30 minutes;

[0024] Step 1.2.5: Transfer the dispersion to a vacuum distillation apparatus and distill to recover ethanol to obtain a graphite-antimony composite dispersion slurry.

[0025] Furthermore, the step 1.3 further includes the following steps:

[0026] Step 1.3.1: Pre-mix the polytetrafluoroethylene matrix premix and the graphite-antimony composite dispersion slurry in a closed container using a pneumatic stirrer for preliminary mixing;

[0027] Step 1.3.2: Transfer the preliminarily mixed materials to the stirring vessel of a low-speed planetary mixer at a temperature of 25-35°C. Add chopped glass fiber in four equal batches using an automatic metering screw feeder, with each batch being fed at an interval of 3-5 minutes at a rate of 100-150 g / min.

[0028] Step 1.3.3: After the addition of the chopped glass fibers, close the feed port of the stirring kettle and start the vacuum system for degassing. Maintain the vacuum degree at -0.095 MPa for 10-20 minutes to obtain a mixed material.

[0029] Step 1.3.4: After degassing, first introduce dry nitrogen to restore the pressure in the kettle to normal, and then transfer the mixed material to a closed storage tank through the bottom discharge valve.

[0030] Furthermore, the step 2 further includes the following steps:

[0031] Step 2.1: Weigh the mixed material prepared in step 1 and place it in the preheated mold. After closing the mold, start the vacuum system and draw the vacuum degree in the mold cavity to 5×10- 2 Pa;

[0032] Step 2.2: Raise the mold temperature to 220°C, apply 10-15 MPa pressure, and maintain the temperature and pressure for 15 minutes;

[0033] Step 2.3: Increase the pressure gradually to 35 MPa at a rate of 0.4-0.8 MPa / min, and simultaneously increase the mold temperature to 320°C at a rate of 3-5°C / min.

[0034] Step 2.4: Gradually increase the pressure to 45 MPa at a rate of 0.4-0.8 MPa / min, while simultaneously raising the mold temperature to 340°C. Maintain the pressure for 30 minutes using an argon gas shielding system.

[0035] Step 2.5: After the pressure is maintained, reduce the pressure to 20 MPa and turn off the argon gas;

[0036] Step 2.6: Reduce the mold temperature to 280°C at a rate of 3-5°C / min, and then reduce the mold temperature to 150°C at a rate of 1-3°C / min. Slowly release the pressure to 3 atmospheres, open the mold, remove the molded product, and allow it to cool naturally.

[0037] Furthermore, the step 3 further includes the following steps:

[0038] Step 3.1: Use radio frequency plasma equipment to polish the surface of the molded product at a frequency of 13-15 MHz;

[0039] Step 3.2: The polished product is heat-treated in a high-precision box-type resistance furnace to obtain a graphite composite cluster wheel product.

[0040] Furthermore, the step 3.2 further includes the following steps:

[0041] Step 3.2.1: Place the polished product on an alumina ceramic tray and place it in the center of the resistance furnace;

[0042] Step 3.2.2: Raise the temperature to 180°C and keep warm for 1-3 hours;

[0043] Step 3.2.3: Continue heating to 230°C and hold for 30-50 minutes. During the holding period, introduce nitrogen gas into the furnace at a flow rate of 100-150 sccm to maintain a positive pressure in the furnace.

[0044] Step 3.2.4: After the insulation is completed, stop heating, keep nitrogen flowing, and naturally cool to 70-80°C; turn off the nitrogen, wait until the temperature in the furnace stabilizes, open the furnace door and take out the graphite composite bundle wheel product.

[0045] In summary, the present invention has the following beneficial effects: the glass fiber bundling wheel prepared by the present application effectively improves the bending strength, impact strength, and wear resistance, reduces the friction coefficient, can achieve zero particle shedding, extends the service life and maintenance cycle of the bundling wheel, and improves production efficiency. DETAILED DESCRIPTION

[0046] The technical solution of the present application is described clearly and completely below; it is obvious that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0047] The present invention discloses a glass fiber cluster wheel based on a graphite composite material, which is made of a composite material comprising the following components by mass fraction: 50%-70% polytetrafluoroethylene, 10%-25% flake graphite, 1%-5% antimony, 3%-10% carbon nanotubes, 2%-8% nano-titanium dioxide, and 5%-15% chopped glass fibers. The polytetrafluoroethylene is used as the matrix material, and the molecular weight is ≥1×10 6 , with a particle size of 20-50μm; flake graphite and antimony are used as lubricating reinforcement phases, the purity of flake graphite is ≥99%, the particle size is 5-15μm, and the aspect ratio is >60; antimony is dispersed in the form of nanoparticles with a particle size of ≤2μm; carbon nanotubes, nano-titanium dioxide, and chopped glass fibers are used as reinforcement phases, the length of the carbon nanotubes is 1-10μm, and the surface is treated with acid oxidation (-COOH content ≥3.5mmol / g); the nano-titanium dioxide is anatase-type with a particle size of 20-50nm; the length of the chopped glass fibers is 50-200μm, and the surface is treated with a silane coupling agent.

[0048] This application optimizes the composite of polytetrafluoroethylene, antimony flake graphite, carbon nanotubes, nano-titanium dioxide, and glass fiber to form a highly wear-resistant, particle-free composite material. The glass fiber cluster wheel made from this graphite composite material has a three-dimensional mesh reinforcement structure formed by carbon nanotubes and glass fiber, and a eutectic phase formed by nano-titanium dioxide and antimony at the polytetrafluoroethylene-graphite interface. This effectively improves the bending strength, impact strength, and wear resistance, reduces the friction coefficient, and can achieve zero particle shedding, extending the cluster wheel's service life and maintenance cycle, and improving production efficiency.

[0049] This embodiment also discloses a method for preparing a glass fiber cluster wheel based on a graphite composite material, comprising the following steps:

[0050] Step 1: Mixing in steps: polytetrafluoroethylene, flake graphite, antimony, carbon nanotubes, nano-titanium dioxide, and chopped glass fibers are mixed in steps according to their mass proportions to obtain a mixed material.

[0051] The specific steps are as follows:

[0052] Step 1.1: premix polytetrafluoroethylene, nano-titanium dioxide, and carbon nanotubes to obtain a polytetrafluoroethylene matrix premix.

[0053] Step 1.1.1: Prepare an ethanol suspension of carbon nanotubes with a mass fraction of 5% to 8%.

[0054] Step 1.1.2: Add polytetrafluoroethylene powder preheated in a hot air circulation drying oven to the cavity of the three-dimensional motion mixer and convey it through a vacuum feeding system. The loading amount should not exceed 70% of the effective volume of the mixer cavity; then add equal amounts of nano-titanium dioxide in batches, specifically in 3 batches, with an interval of 5-10 minutes between each batch. The feeding speed is controlled by a vibrating feeder to ensure uniform dispersion; then use a peristaltic pump to spray the ethanol suspension through an atomizing nozzle at a steady flow rate of 2-5 mL / min; maintain an appropriate distance between the nozzle and the material surface, and set the atomization pressure to 0.2-0.3 MPa.

[0055] Step 1.1.3: Start the three-dimensional motion mixer and set the speed to 18-25 rpm. Mix in alternating forward and reverse rotations, switching directions every 10-15 minutes. Mix for 45-65 minutes at a temperature of 25-35°C, ensuring stable material properties. This will yield a polytetrafluoroethylene matrix premix. Transfer the premix to a sealed transfer container for temporary storage to prevent contamination by external impurities.

[0056] The three-dimensional motion mixer needs to be tested for air tightness before operation. If it passes the test, nitrogen with a purity of ≥99% is filled into the closed cavity to reduce the internal oxygen content to below 50ppm, creating an inert protective atmosphere.

[0057] Step 1.2: Flake graphite and antimony are compositely dispersed to obtain a graphite-antimony composite dispersion slurry.

[0058] Step 1.2.1: Mix the silane coupling agent and anhydrous ethanol under a magnetic stirrer to prepare a pretreatment dispersion; wherein the anhydrous ethanol has a purity of ≥99%, and the silane coupling agent is γ-aminopropyltriethoxysilane, and the addition amount of γ-aminopropyltriethoxysilane is 1.5-3% of the total mass of the graphite and antimony powder.

[0059] Step 1.2.2: Weigh the flake graphite according to the formula and slowly add it to the pretreated dispersion.

[0060] Step 1.2.3: Place the container containing the pretreated dispersion containing flake graphite in a water bath at 55 ± 2°C. Disperse the sample using an ultrasonic cell disruptor for 40-60 minutes. Set the ultrasonic cell disruptor to 1200W, with an amplitude of 60-70% and a pulse mode of 2-4 seconds of operation followed by a 1-second pause. Before use, check the probe for wear and tear. Immerse the probe in the dispersion during operation to ensure uniform transmission of ultrasonic energy.

[0061] Step 1.2.4: Slowly add the dried antimony powder through the vacuum feeding system and continue ultrasonic dispersion for 15-30 minutes. During this stage, monitor the water bath temperature in real time and make fine adjustments using the water bath's built-in temperature control system to ensure that the temperature fluctuation does not exceed ±2°C.

[0062] Step 1.2.5: After the dispersion is completed, the dispersion liquid is transferred to a vacuum distillation apparatus to distill and recover ethanol to obtain a graphite-antimony composite dispersion slurry. The graphite-antimony composite dispersion slurry is then sealed and stored to prevent agglomeration and oxidation.

[0063] Step 1.3: Preliminarily mix the polytetrafluoroethylene matrix premix and the graphite-antimony composite dispersion slurry, then add equal amounts of chopped glass fibers in batches and stir and mix to prepare a mixed material.

[0064] Step 1.3.1: Pre-mix the polytetrafluoroethylene matrix premix and the graphite-antimony composite dispersion slurry in a closed container using an air-driven stirrer for preliminary mixing.

[0065] Step 1.3.2: Start the low-speed planetary mixer and transfer the pre-mixed materials to the mixing vessel. The loading should not exceed 60% of the mixing vessel's effective volume. Monitor the vessel temperature during mixing and maintain it between 25°C and 35°C. Set the low-speed planetary mixer to a speed of 30-50 rpm and a rotational speed of 15-25 rpm. Add chopped glass fiber in four equal batches using an automatic metering screw feeder, with each batch separated by 3-5 minutes. Feed at a rate of 100-150 g / min to ensure even dispersion of the fibers.

[0066] Step 1.3.3: After the addition of the chopped glass fibers is completed, the feed port of the stirring kettle is closed and the vacuum system is turned on for degassing. The vacuum degree is maintained at -0.095 MPa for 10-20 minutes to obtain a mixed material.

[0067] Step 1.3.4: After degassing, first introduce dry nitrogen to restore the pressure in the kettle, and then transfer the mixed material to a closed storage tank through the bottom discharge valve to prevent the material from moisture or oxidation.

[0068] Step 2: Gradient hot pressing molding, quantitatively weigh the above mixed materials and place them in a preheated mold, gradient pressurize and heat the mixed materials in the mold to form the mold, and then reduce the pressure and cool to obtain a molded product.

[0069] A high-precision hydraulic hot press is used, equipped with a programmable temperature control system, pressure sensor, and vacuum-to-inert gas switching device. The forming mold is made of alloy steel with a hard chrome-plated surface, with a roughness of Ra ≤ 0.8μm. The mold size is customized according to product specifications and is preheated to 100°C before being sprayed with a high-temperature release agent.

[0070] The specific steps are as follows:

[0071] Step 2.1: Weigh the mixed material prepared in step 1 and place it in the preheated mold. After closing the mold, start the vacuum system and draw the vacuum degree in the mold cavity to 5×10-2 Pa.

[0072] Step 2.2: Raise the mold temperature to 220°C, apply a pressure of 10-15 MPa, and maintain the temperature and pressure for 15 minutes. During this period, monitor the pressure fluctuations in real time and automatically increase the pressure when the deviation exceeds ±0.5 MPa.

[0073] Step 2.3: Start the pressure and temperature linear increase program, gradually increase the pressure to 35MPa at a rate of 0.4-0.8MPa / min, and at the same time increase the mold temperature to 320℃ at a rate of 3-5℃ / min; the pressure and temperature are controlled using the PID adjustment algorithm to ensure parameter stability.

[0074] Step 2.4: Continue to gradually increase the pressure to 45 MPa at a rate of 0.4-0.8 MPa / min. Simultaneously, raise the mold temperature to 340°C. Maintain the pressure for 30 minutes using an argon gas protection system. The argon purity should be ≥99%, and the flow rate should be controlled at 5-7 L / min to maintain a positive pressure in the mold cavity to prevent material oxidation. During this pressure-maintaining process, perform pressure compensation every 10-15 minutes.

[0075] Step 2.5: After the pressure maintenance is completed, first reduce the pressure to 20MPa and turn off the argon gas.

[0076] Step 2.6: Start the gradient cooling program, reduce the mold temperature to 280°C at a rate of 3-5°C / min, and then reduce the mold temperature to 150°C at a rate of 1-3°C / min. Slowly release the pressure to 3 atmospheres, open the mold, remove the molded product, and cool it naturally.

[0077] Step 3: Post-processing: first polish the surface of the molded product, and then perform heat treatment to obtain a graphite composite material cluster wheel product.

[0078] The specific steps are as follows:

[0079] Step 3.1: Use radio frequency plasma equipment to polish the surface of the molded product at a frequency of 13-15MHz. Before the radio frequency plasma equipment is operated, the vacuum chamber needs to be leak tested using a helium mass spectrometer to ensure that the cavity leakage rate is ≤1×10- 6 Pa·m 3 / s. Perform power calibration on the RF power supply to ensure output stability, with an error range of ±0.1W / cm 2 Configure the gas supply system, maintain the Ar gas cylinder pressure at 7-10MPa, and maintain the CF4 gas cylinder pressure at 5-7MPa.

[0080] The polishing process is as follows: the molded product is placed on a customized fixture to ensure that the surface of the product maintains a certain vertical distance from the plasma generation area. The fixture is made of polytetrafluoroethylene to prevent the introduction of impurities; the vacuum chamber is closed, the vacuum pump is started, and the vacuum degree in the chamber is pumped to 5×10- 3 Pa; according to the gas ratio of Ar (70-80%) + CF4 (10-20%), the gas is introduced, the Ar gas flow rate is controlled by the mass flow meter to 60-80 sccm (standard milliliters per minute), and the CF4 gas flow rate is 10-20 sccm. After the gas flow rate is stable, the RF power supply is turned on and the power is adjusted to make the power density reach 2.5W / cm 2 The treatment time is 12 minutes in total. The front side of the molded product is first treated for 6 minutes. After the treatment is completed, the molded product is turned over by a mechanical flipping device and the back side is treated for another 6 minutes. After the treatment is completed, the RF power supply is turned off, the gas supply is stopped, the inflation valve is opened, and dry air is slowly filled to normal pressure, and the molded product is taken out.

[0081] Step 3.2: Heat-treat the polished product in a high-precision box-type resistance furnace to obtain a graphite composite cluster wheel product. The high-precision box-type resistance furnace is equipped with a programmable temperature control system with a temperature control accuracy of ±2°C.

[0082] Step 3.2.1: Place the polished product on an alumina ceramic tray and place it in the center of the resistance furnace.

[0083] Step 3.2.2: Start the temperature control program, raise the temperature to 180℃, and keep it warm for 1-3 hours. During this period, check the status of the product through the observation window on the furnace wall. If any abnormal deformation occurs, stop heating immediately.

[0084] Step 3.2.3: Continue heating to 230°C and keep warm for 30-50 minutes. During the warming period, introduce nitrogen into the furnace at a flow rate of 100-150 sccm to maintain a positive pressure in the furnace.

[0085] Step 3.2.4: After the insulation is completed, stop heating, keep nitrogen flowing, and naturally cool to 70-80°C; turn off the nitrogen, wait until the temperature in the furnace stabilizes, open the furnace door and take out the graphite composite bundle wheel product.

[0086] The graphite composite material clustering wheel prepared by the above method of the present application was tested and compared with the traditional pure graphite clustering wheel, and the following conclusions were drawn.

[0087] Compared with traditional pure graphite cluster wheels, the mechanical properties of this application cluster wheel are significantly improved. The three-dimensional reinforced network formed by carbon nanotubes and glass fibers increases the bending strength by 157%. The interfacial bonding strength is improved by antimony and nano-titanium dioxide, and the impact strength is 2.9 times that of traditional graphite cluster wheels.

[0088]

[0089] Table 1: Comparison of mechanical properties of the cluster wheel in this application and traditional pure graphite cluster wheel

[0090] The cluster wheel of this application uses polytetrafluoroethylene + graphite + carbon nanotubes for synergistic lubrication and plasma polishing technology to reduce the wear of traditional materials to 1 / 7, and the cumulative wear after 200 hours of use is only 3.8 mg. As shown in Table 2,

[0091]

[0092]

[0093] Table 2: Comparison of friction performance between the cluster wheel of this application and the traditional pure graphite cluster wheel

[0094] The addition of antimony to the cluster wheel of this application increases the thermal deformation temperature from 120℃ to 160℃, a 33% increase; it remains stable at 200℃ and is suitable for high-temperature glass fiber production environments.

[0095]

[0096] Table 3: Comparison of deformation between the cluster wheel of this application and the traditional pure graphite cluster wheel

[0097] The cluster wheel of this application uses polytetrafluoroethylene to densely wrap graphite, which reduces the amount of particle shedding during use by 100%, and there is still no visible pollution on the fiber surface after running for 1000 hours.

[0098]

[0099]

[0100] Table 4: Comparison of particle residues after operation between the cluster wheel of this application and the traditional pure graphite cluster wheel

[0101] The cluster wheel of this application is composited with multiple materials to form a dense gradient layer in the cross section, which greatly reduces the porosity. Nano-titanium dioxide forms a "pinning effect" at the interface to inhibit crack propagation. As shown in Table 5,

[0102] Observation area Traditional graphite cluster wheel This application cluster wheel Surface morphology Graphite exposed, with obvious cracks PTFE completely encapsulates graphite, without defects Cross-sectional structure Loose and porous (porosity 12%) Dense gradient layer (porosity 0.9%) Element distribution C element aggregation (phase separation) C / Sb / Ti uniform distribution (EDS surface scanning)

[0103] Table 5: Microstructure analysis of the cluster wheel of this application and the traditional pure graphite cluster wheel

[0104] Compared with the traditional pure graphite clustering wheel, the life of the clustering wheel of this application is extended by nearly 3 times and the downtime is reduced by 67%. As shown in Table 6,

[0105] index Traditional graphite cluster wheel This application cluster wheel Improvement Average lifespan (h) 1,200-1,500 3,800-4,200 280％ Maintenance cycle (h) 140 430 207％

[0106] Table 6: Comparison of the life of the cluster wheel in this application and the traditional pure graphite cluster wheel

[0107] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A glass fiber cluster wheel based on graphite composite material, characterized in that: The composite material is made of the following components in mass fraction: 50%-70% of polytetrafluoroethylene, 10%-25% of flake graphite, 1%-5% of antimony, 3%-10% of carbon nanotubes, 2%-8% of nano titanium dioxide, and 5%-15% of chopped glass fibers.

2. A method for preparing a glass fiber cluster wheel based on graphite composite material, characterized in that: The following steps are involved: Step 1: Mixing in steps: polytetrafluoroethylene, flake graphite, antimony, carbon nanotubes, nano-titanium dioxide, and chopped glass fibers in steps according to their mass proportions to obtain a mixed material; Step 2: Gradient hot pressing molding, quantitatively weighing the above mixed material and placing it in a preheated mold, gradiently increasing pressure and temperature to hot press the mixed material in the mold, and then reducing pressure and cooling to obtain a molded product; Step 3: Post-processing: first polish the surface of the molded product, and then perform heat treatment to obtain a graphite composite material cluster wheel product.

3. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 2, characterized in that: The step 1 further comprises the following steps: Step 1.1: premixing polytetrafluoroethylene, nano-titanium dioxide, and carbon nanotubes to obtain a polytetrafluoroethylene matrix premix; Step 1.2: dispersing flake graphite and antimony to obtain a graphite-antimony composite dispersion slurry; Step 1.3: Preliminarily mix the polytetrafluoroethylene matrix premix and the graphite-antimony composite dispersion slurry, then add equal amounts of chopped glass fibers in batches and stir and mix to prepare a mixed material.

4. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 3, wherein: The step 1.1 further comprises the following steps: Step 1.1.1: Prepare a 5%-8% carbon nanotube suspension in ethanol; Step 1.1.2: Add polytetrafluoroethylene powder preheated in a hot air circulation drying oven to the cavity of the three-dimensional motion mixer. Then, add equal amounts of nano-titanium dioxide in batches. Then, spray the ethanol suspension through the atomizing nozzle at a steady flow rate of 2-5 mL / min. Step 1.1.3: Start the three-dimensional motion mixer and mix in a forward and reverse alternating operation mode, switching the direction every 10-15 minutes, with a mixing time of 45-65 minutes and a mixing temperature of 25-35° C. to obtain a polytetrafluoroethylene matrix premix.

5. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 3, wherein: The step 1.2 further comprises the following steps: Step 1.2.1: Mix the silane coupling agent and anhydrous ethanol under a magnetic stirrer to prepare a pretreatment dispersion; Step 1.2.2: Add flake graphite to the pre-treated dispersion; Step 1.2.3: Place the container containing the pretreated dispersion containing flake graphite in a constant temperature water bath at 55±2°C and start the ultrasonic cell disruptor for 40-60 minutes. Step 1.2.4: Add dried antimony powder and continue ultrasonic dispersion for 15-30 minutes; Step 1.2.5: Transfer the dispersion to a vacuum distillation apparatus and distill to recover ethanol to obtain a graphite-antimony composite dispersion slurry.

6. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 3, wherein: The step 1.3 further comprises the following steps: Step 1.3.1: Pre-mix the polytetrafluoroethylene matrix premix and the graphite-antimony composite dispersion slurry in a closed container using a pneumatic stirrer for preliminary mixing; Step 1.3.2: Transfer the preliminarily mixed materials to the stirring vessel of a low-speed planetary mixer at a temperature of 25-35°C. Add chopped glass fiber in four equal batches using an automatic metering screw feeder, with each batch being fed at an interval of 3-5 minutes at a rate of 100-150 g / min. Step 1.3.3: After the addition of the chopped glass fibers is completed, the feed port of the stirring kettle is closed and the vacuum system is turned on for degassing. The vacuum degree is maintained at -0.095 MPa for 10-20 minutes to obtain a mixed material. Step 1.3.4: After degassing, first introduce dry nitrogen to restore the pressure in the kettle to normal, and then transfer the mixed material to a closed storage tank through the bottom discharge valve.

7. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 2, wherein: The step 2 further comprises the following steps: Step 2.1: Quantitatively weigh the mixed material prepared in step 1 and place it in the preheated mold. After closing the mold, start the vacuum system and draw the vacuum degree in the mold cavity to 5×10 -2 Pa; Step 2.2: Raise the mold temperature to 220°C, apply 10-15 MPa pressure, and maintain the temperature and pressure for 15 minutes; Step 2.3: Increase the pressure gradually to 35 MPa at a rate of 0.4-0.8 MPa / min, and simultaneously increase the mold temperature to 320°C at a rate of 3-5°C / min; Step 2.4: Gradually increase the pressure to 45 MPa at a rate of 0.4-0.8 MPa / min, while simultaneously raising the mold temperature to 340°C; maintain the pressure for 30 minutes using an argon protection system; Step 2.5: After the pressure is maintained, reduce the pressure to 20 MPa and turn off the argon gas; Step 2.6: Reduce the mold temperature to 280°C at a rate of 3-5°C / min, and then reduce the mold temperature to 150°C at a rate of 1-3°C / min. Slowly release the pressure to 3 atmospheres, open the mold, remove the molded product, and allow it to cool naturally.

8. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 2, wherein: The step 3 further comprises the following steps: Step 3.1: Use radio frequency plasma equipment to polish the surface of the molded product at a frequency of 13-15 MHz; Step 3.2: The polished product is heat-treated in a high-precision box-type resistance furnace to obtain a graphite composite cluster wheel product.

9. The method for preparing a glass fiber cluster wheel based on graphite composite material according to claim 8, characterized in that: The step 3.2 further comprises the following steps: Step 3.2.1: Place the polished product on an alumina ceramic tray and place it in the center of the resistance furnace; Step 3.2.2: Raise the temperature to 180°C and keep warm for 1-3 hours; Step 3.2.3: Continue heating to 230°C and hold for 30-50 minutes. During the holding period, introduce nitrogen gas into the furnace at a flow rate of 100-150 sccm to maintain a positive pressure in the furnace. Step 3.2.4: After the insulation is completed, stop heating, keep nitrogen flowing, and cool naturally to 70-80°C; turn off the nitrogen, wait until the temperature in the furnace stabilizes, open the furnace door and take out the graphite composite bundle wheel product.

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