A carbon fiber reinforced ceramic-based brake pad

Abstract

This invention provides a carbon fiber reinforced ceramic-based brake pad, belonging to the technical field of braking friction materials. Its raw materials include zirconium oxide fiber, nitrile rubber, modified phenolic resin, carbon fiber, alumina fiber, barite, aramid fiber, sepiolite, ceramic fiber, silicon carbide, expanded vermiculite, graphite, corundum, and zircon. The carbon fiber uses polyacrylonitrile as a precursor, first undergoing stretching treatment under specific conditions, then sequentially undergoing pre-oxidation, low-temperature carbonization, and high-temperature carbonization, finally being graphitized to obtain the finished product. This invention significantly improves the strength, toughness, and elastic modulus of carbon fiber, using it as a reinforcing material to fully improve the mechanical properties of the brake pad. This invention maintains a high coefficient of friction even under heavy loads and low-speed heavy braking conditions. Furthermore, this invention has a stable structure, minimal mass loss, and excellent high-temperature performance, making it suitable for braking systems of heavy-duty vehicles, exhibiting excellent braking performance and durability.

Description

Technical Field

[0001] This invention relates to the field of braking friction materials technology, specifically to a carbon fiber reinforced ceramic-based brake pad. Background Technology

[0002] Ceramic-based brake pads are among the best-performing brake pad types currently available. They avoid the noise and dust problems caused by steel fiber corrosion, resulting in a cleaner and quieter ride. They also cause less wear on the brake discs and have a lifespan approximately twice that of ordinary brake pads. Furthermore, they exhibit very stable high-temperature performance, avoiding the drastic performance degradation caused by the melting of traditional brake pads at high temperatures. In addition, ceramic-based brake pads have a lower specific gravity, minimizing the increase in vehicle weight. They offer better overall braking response and a stable coefficient of friction. As a clean, environmentally friendly, and high-performance brake pad product, they are gradually gaining widespread application in the civilian and high-performance vehicle markets.

[0003] In terms of composition, the core components of ceramic-based brake pads consist of reinforcing fibers, mineral fillers, a binder matrix, friction modifiers, anti-wear lubricants, and elastic toughening agents. By mass percentage, reinforcing fibers comprise approximately 25% to 40%, fillers 10% to 30%, the binder matrix 15% to 30%, and the remaining components are distributed in appropriate proportions. Regarding the manufacturing process, the mixed raw materials are first fed into a mold or press, and the pressure and speed are controlled to form a brake pad blank with a regular shape and uniform density. This blank then enters a high-temperature sintering process, where it is placed in a sintering furnace and sintered at a strictly controlled temperature to allow the ceramic particles to bond together, ultimately forming a dense and stable ceramic structure. After sintering, the finished product is obtained through finishing processes such as grinding, grooving, and drilling.

[0004] In existing technologies, ordinary ceramic-based brake pads are not suitable for heavy-duty vehicles. Ceramic-based materials have weak shear and impact resistance, and the instantaneous loads and severe vibrations during braking in heavy-duty vehicles can easily lead to material cracking and spalling. In contrast, semi-metallic or low-metallic brake pads have higher toughness and plastic deformation absorption capacity. Furthermore, heavy-duty vehicles frequently start and stop and experience heavy braking at low speeds. Ceramic-based brake pads have a low coefficient of friction and slow response at low temperatures, while semi-metallic brake pads can provide stable high braking force even when cold. The thermal stability advantage of ceramic-based brake pads is only prominent during continuous high-speed braking (such as in sports cars and racing cars), which is not typical for heavy-duty trucks. Summary of the Invention

[0005] The present invention aims to address the technical deficiencies of the prior art by providing a carbon fiber reinforced ceramic-based brake pad, thereby solving the technical problem that long ceramic-based brake pads are not suitable for heavy-duty vehicles.

[0006] Another technical problem that this invention aims to solve is how to improve the performance of ceramic-based brake pads under heavy-duty vehicle braking conditions.

[0007] To achieve the above technical objectives, the present invention adopts the following technical solution: A carbon fiber reinforced ceramic-based brake pad, wherein the raw materials of the carbon fiber reinforced ceramic-based brake pad include the following components in parts by weight: 2-6 parts of zirconium oxide fiber, 5-9 parts of nitrile rubber, 5-10 parts of modified phenolic resin, 8-12 parts of carbon fiber, 7-15 parts of alumina fiber, 3-15 parts of barite, 3-7 parts of aramid fiber, 3-6 parts of sepiolite, 5-10 parts of ceramic fiber, 5-12 parts of silicon carbide, 7-13 parts of expanded vermiculite, 2-6 parts of graphite, 2-6 parts of corundum, and 9-14 parts of zircon; The carbon fiber is prepared by the following method: 1) Take polyacrylonitrile precursor fibers and perform oiling and stretching pretreatment in an oiling and stretching winding equipment. The treatment reagent used for oiling and stretching pretreatment is an antistatic agent. 2) Pre-oxidation treatment is carried out at 190~260℃ to obtain pre-oxidized fiber; 3) The pre-oxidized fiber obtained in step 2) is subjected to low-temperature carbonization treatment at 360~750℃ to obtain low-temperature carbonized filament; during the low-temperature carbonization treatment, the temperature of the low-temperature waste outlet is controlled at 420~450℃, and the single filament tension is controlled at 0.55~0.6CN. 4) The low-temperature carbonized filaments obtained in step 3) are subjected to high-temperature carbonization treatment at 1200~1750℃ to obtain high-temperature carbonized filaments; during the high-temperature carbonization treatment, the filament tension is controlled at 2.85~3.15CN; 5) The high-temperature carbonized filaments obtained in step 4) are graphitized at 2000~2100℃ to obtain carbon fibers; the filament tension is controlled at 3.5~3.9 CN during the graphitization process; after cooling, the carbon fibers are washed with water, dried and wound up in sequence.

[0008] Preferably, the carbon fiber has a tensile strength ≥ 5700 MPa, strength CV ≤ 5%, elastic modulus ≥ 370 GPa, modulus CV ≤ 35%, and elongation at break ≥ 1.5%.

[0009] Preferably, the carbon fiber has a length of 5-10 mm and a diameter of 8-15 μm.

[0010] Preferably, the raw materials for the carbon fiber reinforced ceramic-based brake pad include the following components in parts by weight: 3.7 parts zirconium oxide fiber, 7.5 parts nitrile rubber, 9.2 parts modified phenolic resin, 11 parts carbon fiber, 8.4 parts alumina fiber, 5.5 parts barite, 6.2 parts aramid fiber, 4.7 parts sepiolite, 6.9 parts ceramic fiber, 10.5 parts silicon carbide, 8.4 parts expanded vermiculite, 2.2 parts graphite, 2.7 parts corundum, and 9.6 parts zircon.

[0011] Preferably, in step 1), the polyacrylonitrile precursor fiber has a strength ≥ 8.0 CN / dtex and a modulus ≥ 100 CN / dtex.

[0012] Preferably, in step 1), the treatment reagent used for the oiling and stretching pretreatment is an aqueous solution of a quaternary ammonium salt antistatic agent with a concentration of 0.05 wt%.

[0013] Preferably, in step 1), the draw ratio corresponding to the oiling and stretching pretreatment process is 0.15%, the monofilament tension of the fiber is controlled to be 1.8 CN during the oiling and stretching pretreatment process, and the moisture content obtained after the oiling and stretching pretreatment is controlled to be 16 wt% by the pressure roller.

[0014] Preferably, in step 2), the ratio of the core diameter to the sheath diameter of the pre-oxidized fiber obtained by the pre-oxidation treatment is 0.3.

[0015] Preferably, the carbon fiber strength of the high-temperature carbonized filament obtained in step 4) is controlled at 6200~6600MPa.

[0016] Preferably, the pre-oxidation treatment sequentially passes through the following temperature nodes: 190℃, 215℃, 228℃, 241℃, 250℃, and 260℃; the low-temperature carbonization treatment sequentially passes through the following temperature nodes: 360℃, 450℃, 550℃, 665℃, and 750℃; and the high-temperature carbonization treatment sequentially passes through the following temperature nodes: 1200℃, 1420℃, 1660℃, 1750℃, and 1520℃.

[0017] The production process is as follows: 1) The basic surface layer material is prepared by sequentially adding the formulated amounts of nitrile rubber, alumina fiber, barite powder, expanded vermiculite powder, zirconium oxide fiber, and corundum powder into a spherical automatic feeding tank; 2) The ceramic fiber, silicon carbide, carbon fiber, sepiolite powder, graphite, and zircon powder of the formula are added sequentially into a spherical automatic feeding tank to prepare the reinforcing surface material; 3) The base surface material, the reinforcing surface material, and the formulated amounts of modified phenolic resin and aramid fiber are mixed in an automatic mixer to obtain a composite surface material; 4) Place the composite surface material and the base plate together in a hot press to press the brake pad semi-finished product; 5) The brake pad semi-finished product is grooved and chamfered by CNC machine tool. The tool speed is 2000-2200r / min, the feed depth is 300-500mm, the groove width is 2-3mm, and the groove depth is 3 / 5 of the composite working layer. 6) Place the semi-finished brake pads processed in step 5) on a heat treatment device with the composite surface facing down, hot press, and cool to obtain the finished product.

[0018] This invention provides a carbon fiber reinforced ceramic-based brake pad. This technical solution utilizes a novel friction material formulation based on high-performance carbon fibers. By subjecting the carbon fiber to a specific oiling and drawing pretreatment, the differences in orientation and structure between batches of precursor fibers caused by varying storage periods and environments can be eliminated, improving the batch-to-batch and batch-to-batch stability of carbon fiber performance. By using an additive solution during the oiling and drawing pretreatment process, water molecules can penetrate the precursor fiber, increasing its plasticity and thus improving the draw ratio in the initial pre-oxidation stage. This enhances fiber orientation, strength, and modulus, mitigates fiber breakage during high-ratio drawing in pre-oxidation, and comprehensively improves the physicochemical properties and appearance of the carbon fiber.

[0019] This invention uses high-performance carbon fiber as a reinforcing material, combined with zirconia fiber, alumina fiber, barite, ceramic fiber, and other components to form a friction material formulation. Regarding the formulation components, zirconia fiber possesses oxidation and corrosion resistance, low thermal conductivity, and superior high-temperature performance; barite improves and stabilizes the coefficient of friction, and also reduces wear and braking noise; expanded vermiculite reduces product density and braking noise, and increases elasticity; graphite stabilizes the coefficient of friction, accelerates the dispersion of frictional heat, and improves the thermal stability of the brake pads. Nitrile rubber and modified phenolic resin are used as binders to bond the formulation components into a unified whole, ensuring mechanical strength.

[0020] This invention significantly improves the frictional properties of materials, especially maintaining a high coefficient of friction under heavy loads and low-speed heavy braking conditions. Moreover, the invention has a stable structure, minimal mass loss, and excellent high-temperature performance, making it suitable for braking systems of heavy-duty vehicles, and exhibiting excellent braking performance and durability. Attached Figure Description

[0021] Figure 1 This is a scanning electron microscope image of a partial cross-section of the composite surface material in Embodiment 1 of the present invention. Detailed Implementation

[0022] The specific embodiments of the present invention will be described in detail below. To avoid excessive and unnecessary detail, well-known structures or functions will not be described in detail in the following embodiments. The approximate language used in the following embodiments is for quantitative purposes, indicating that a certain degree of variation in quantity is permissible without changing the basic function. Unless otherwise defined, the technical and scientific terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art to which this invention pertains.

[0023] Example 1 A carbon fiber reinforced ceramic-based brake pad, wherein the raw materials of the carbon fiber reinforced ceramic-based brake pad include the following components in parts by weight: 3.7 parts of zirconium oxide fiber, 7.5 parts of nitrile rubber, 9.2 parts of modified phenolic resin, 11 parts of carbon fiber, 8.4 parts of alumina fiber, 5.5 parts of barite, 6.2 parts of aramid fiber, 4.7 parts of sepiolite, 6.9 parts of ceramic fiber, 10.5 parts of silicon carbide, 8.4 parts of expanded vermiculite, 2.2 parts of graphite, 2.7 parts of corundum, and 9.6 parts of zircon; The carbon fiber is prepared by the following method: 1) Take polyacrylonitrile precursor fibers and perform oiling and stretching pretreatment in an oiling and stretching winding equipment. The treatment reagent used for oiling and stretching pretreatment is an antistatic agent. 2) The fiber is pre-oxidized by passing it through the following temperature nodes in sequence: 190℃, 215℃, 228℃, 241℃, 250℃, and 260℃. 3) The pre-oxidized fiber obtained in step 2) is subjected to low-temperature carbonization treatment at the following temperature nodes in sequence: 360℃, 450℃, 550℃, 665℃ and 750℃ to obtain low-temperature carbonized filament; during the low-temperature carbonization treatment, the temperature of the low-temperature waste outlet is controlled at 420~450℃ and the single filament tension is controlled at 0.55~0.6CN. 4) The low-temperature carbonized filaments obtained in step 3) are subjected to high-temperature carbonization treatment at the following temperature nodes: 1200℃, 1420℃, 1660℃, 1750℃, and 1520℃ to obtain high-temperature carbonized filaments; during the high-temperature carbonization treatment, the filament tension is controlled at 2.85~3.15CN; 5) The high-temperature carbonized filaments obtained in step 4) are graphitized at 2000~2100℃ to obtain carbon fibers; the filament tension is controlled at 3.5~3.9 CN during the graphitization process; after cooling, the carbon fibers are washed with water, dried and wound up in sequence.

[0024] The carbon fiber has a tensile strength ≥ 5700 MPa, strength CV ≤ 5%, elastic modulus ≥ 370 GPa, modulus CV ≤ 35%, and elongation at break ≥ 1.5%. The carbon fiber has a length of 5~10 mm and a diameter of 8~15 μm.

[0025] In step 1), the polyacrylonitrile precursor fiber has a strength ≥ 8.0 CN / dtex and a modulus ≥ 100 CN / dtex. The treatment reagent used for the oiling and drawing pretreatment is a 0.05 wt% aqueous solution of a quaternary ammonium salt antistatic agent. The draw ratio corresponding to the oiling and drawing pretreatment process is 0.15%, and the monofilament tension of the fiber is controlled at 1.8 CN during the oiling and drawing pretreatment process. The moisture content obtained after the oiling and drawing pretreatment is controlled at 16 wt% by the pressure roller. In step 2), the ratio of the core diameter to the sheath diameter of the pre-oxidized fiber obtained by the pre-oxidation treatment is 0.3. The high-temperature carbonized filament obtained in step 4) has a carbon fiber strength controlled at 6200~6600 MPa.

[0026] The production process is as follows: a) The formula amounts of nitrile rubber, alumina fiber, barite powder, expanded vermiculite powder, zirconium oxide fiber, and corundum powder are sequentially added to a spherical automatic feeding tank to prepare the base surface material; b) The ceramic fiber, silicon carbide, carbon fiber, sepiolite powder, graphite, and zircon powder in the formula are added sequentially into a spherical automatic feeding tank to prepare the reinforcing surface material; c) The base surface material, the reinforcing surface material, and the formulated amounts of modified phenolic resin and aramid fiber are mixed in an automatic mixer to obtain a composite surface material; a scanning electron microscope image of a partial cross-section of the composite surface material is shown below. Figure 1 As shown; d) Place the composite surface material and the base plate together in a hot press to press the brake pad semi-finished product; e) Grooving and chamfering of brake pad semi-finished products are performed using CNC machine tools. The tool speed is 2000-2200r / min, the feed depth is 300-500mm, the grooving width is 2-3mm, and the grooving depth is 3 / 5 of the composite working layer. f) Place the semi-finished brake pads processed in step e) on a heat treatment device with the composite surface facing down, hot press, and cool to obtain the finished product.

[0027] Example 2 A carbon fiber reinforced ceramic-based brake pad, wherein the raw materials of the carbon fiber reinforced ceramic-based brake pad include the following components in parts by weight: 4 parts zirconium oxide fiber, 6 parts nitrile rubber, 8 parts modified phenolic resin, 10.4 parts carbon fiber, 13 parts alumina fiber, 12.5 parts barite, 6.1 parts aramid fiber, 4.9 parts sepiolite, 7.7 parts ceramic fiber, 8.5 parts silicon carbide, 10 parts expanded vermiculite, 4.4 parts graphite, 3.6 parts corundum, and 11 parts zircon; wherein the carbon fiber is prepared by the following method: 1) Take polyacrylonitrile precursor fibers and perform oiling and stretching pretreatment in an oiling and stretching winding equipment. The treatment reagent used for oiling and stretching pretreatment is an antistatic agent. 2) Pre-oxidation treatment is carried out at 190~260℃ to obtain pre-oxidized fibers; 3) The pre-oxidized fiber obtained in step 2) is subjected to low-temperature carbonization treatment at 360~750℃ to obtain low-temperature carbonized filament; during the low-temperature carbonization treatment, the temperature of the low-temperature waste outlet is controlled at 420~450℃, and the single filament tension is controlled at 0.55~0.6CN. 4) The low-temperature carbonized filaments obtained in step 3) are subjected to high-temperature carbonization treatment at 1200~1750℃ to obtain high-temperature carbonized filaments; during the high-temperature carbonization treatment, the filament tension is controlled at 2.85~3.15CN; 5) The high-temperature carbonized filaments obtained in step 4) are graphitized at 2000~2100℃ to obtain carbon fibers; the filament tension is controlled at 3.5~3.9 CN during the graphitization process; after cooling, the carbon fibers are washed with water, dried, and wound up in sequence. The production process is the same as in Example 1.

[0028] Comparative Example 1 A method for preparing a ceramic-based brake pad, comprising the following steps: S1: Weigh 25g of reinforcing fiber, 10g of filler, 5g of phenolic resin powder, 1g of nitrile rubber powder, and 1g of modified molybdenum disulfide, and stir and mix for 5 minutes. S2: The mixture is pressed into shape and then heat-treated to obtain ceramic-based brake pads.

[0029] The reinforcing fiber is carbon fiber.

[0030] The filler is barite.

[0031] The pressing pressure is 3 MPa, and the time is 5 minutes.

[0032] The heat treatment process is as follows: hold at 130℃ for 30 min; hold at 140℃ for 30 min; hold at 160℃ for 30 min; hold at 180℃ for 90 min; and hold at 200℃ for 150 min.

[0033] The method for preparing the modified molybdenum disulfide is as follows: A1: Add 100g of molybdenum disulfide, 4g of γ-methacryloyloxypropyltrimethoxysilane, and 1000g of dimethyl sulfone to reactor 1 and react at 40°C for 10 hours. A2: Add 10g of p-terphenyl-4,4'-dithiol and 3g of sodium methoxide, and react at 80℃ for 100 minutes. This step and the subsequent step A4 are both carried out under nitrogen protection. A3: Add 2g of 10,13-epoxy-10,12-octadecadienoic acid, 4g of zirconium nitrate, and 100g of dimethyl sulfone to reactor 2 and react at 30°C for 5 hours to generate a 10,13-epoxy-10,12-octadecadienoic acid / zirconium complex. A4: Add the product from reactor 2 to reactor 1 and react at 80°C for 100 minutes to obtain modified molybdenum disulfide.

[0034] Comparative Example 2 A ceramic-based brake pad comprises the following raw materials in parts by weight: 18 parts modified phenolic resin, 10 parts modified alumina fiber, 6 parts mullite hollow spheres, 4 parts expanded vermiculite, 3 parts tungsten disulfide, 2.5 parts nano-silica, 7 parts high-temperature resistant fiber, and 3 parts polyimide micro powder.

[0035] The preparation of modified phenolic resin includes the following steps: phenolic resin prepolymer is dispersed in anhydrous ethanol (mass ratio of phenolic resin prepolymer to anhydrous ethanol is 3:5), then cashew nut shell oil is added, and after stirring evenly, the temperature is raised to 80℃ for grafting (during which the hydroxyl value is detected by sampling; when the hydroxyl value drops to 150 mg KOH / g-200 mg KOH / g, the grafting reaction is complete, and the grafting rate is controlled at 20%). Then, sodium tetraphenylborate (boron crosslinking agent, mass ratio of sodium tetraphenylborate to phenolic resin prepolymer is 1:10) is added, and after stirring evenly, the temperature is raised to 130℃ for crosslinking (reaction for 4 hours). After cooling, anhydrous ethanol is added (solid-liquid ratio is 1:1), and after stirring for 30 minutes, the mixture is filtered to remove unreacted sodium tetraphenylborate, and then dried to obtain modified phenolic resin.

[0036] The modified alumina fiber is obtained by modifying alumina fiber with γ-methacryloxypropyltrimethoxysilane (silane modifier). Specifically, γ-methacryloxypropyltrimethoxysilane is dissolved in a mixed solvent (ethanol:deionized water = 9:1, volume ratio), and then alumina fiber with surface impurities removed is added (the mass ratio of alumina fiber to γ-methacryloxypropyltrimethoxysilane is 1:0.05). The mixture is stirred for 1 hour, the precipitate is filtered, washed with deionized water, and dried to obtain the modified alumina fiber.

[0037] Among them, the high-temperature resistant fiber is basalt fiber and carbon fiber in a mass ratio of 1:1.

[0038] The preparation method includes the following steps: mixing modified phenolic resin, alumina fiber, mullite hollow spheres, expanded vermiculite, tungsten disulfide, nano-silica, high-temperature resistant fiber and imide micro powder (mixing at 250 r / min for 30 min in a mixer), pouring the mixed material into a mold and pressing it into shape (pressing at 8 MPa pressure for 2 min), curing (curing at 160℃ for 2 h), and then performing a second curing (second curing at 300℃ for 1 h) to obtain ceramic-based brake pads.

[0039] Experimental Example The material properties, coefficient of friction, wear amount, and actual braking performance of the brake pads in each embodiment and comparative example were tested respectively. The specific test methods are as follows: (1) Material properties: The Brinell hardness was tested using an HB-3000B Brinell hardness tester to measure the Brinell hardness of the friction material. (2) Friction coefficient: MMW-1A universal friction and wear tester was selected. Before the test, the surface of the test block was polished to ensure that the material surface was smooth and flat. The pressure load was 30N, the speed was 200r / min, and the friction time was 10min. The small thrust ring sample was made of 32GrMn steel with a mating diameter of 28mm. The average value was taken after 5 measurements. (3) Wear amount: The wear amount is measured by the mass loss of the test block per unit time. The turntable speed is 330r / min, and the test block is worn on the turntable for 180min. The wear amount is weighed to measure the percentage of the original mass.

[0040] (4) Braking performance: Based on GB 12676-2014, the braking distance, average deceleration and braking stability of a fully loaded trailer with an initial speed of 50 km / h were tested.

[0041] The experimental results are shown in Table 1 below.

[0042] Table 1. Performance test results of brake pads in each embodiment and comparative example.

[0043] The above test results show that the brake pads of the present invention have a higher Brinell hardness and a significantly higher coefficient of friction than the comparative example, and under the same experimental conditions, the wear amount is only 22% to 33% of that of the comparative example. In addition, the braking distance of the present invention applied to a fully loaded trailer is significantly shorter than that of the comparative example, and the braking performance of the two wheels is relatively similar.

[0044] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A carbon fiber reinforced ceramic-based brake pad, characterized in that, The raw materials for this carbon fiber reinforced ceramic-based brake pad include the following components by weight: 2-6 parts zirconium oxide fiber, 5-9 parts nitrile rubber, 5-10 parts modified phenolic resin, 8-12 parts carbon fiber, 7-15 parts alumina fiber, 3-15 parts barite, 3-7 parts aramid fiber, 3-6 parts sepiolite, 5-10 parts ceramic fiber, 5-12 parts silicon carbide, 7-13 parts expanded vermiculite, 2-6 parts graphite, 2-6 parts corundum, and 9-14 parts zircon. The carbon fiber is prepared by the following method: 1) Take polyacrylonitrile precursor fibers and perform oiling and stretching pretreatment in an oiling and stretching winding equipment. The treatment reagent used for oiling and stretching pretreatment is an antistatic agent. 2) Pre-oxidation treatment is carried out at 190~260℃ to obtain pre-oxidized fibers; 3) The pre-oxidized fiber obtained in step 2) is subjected to low-temperature carbonization treatment at 360~750℃ to obtain low-temperature carbonized filament; during the low-temperature carbonization treatment, the temperature of the low-temperature waste outlet is controlled at 420~450℃, and the single filament tension is controlled at 0.55~0.6CN. 4) The low-temperature carbonized filaments obtained in step 3) are subjected to high-temperature carbonization treatment at 1200~1750℃ to obtain high-temperature carbonized filaments; during the high-temperature carbonization treatment, the filament tension is controlled at 2.85~3.15CN; 5) The high-temperature carbonized filaments obtained in step 4) are graphitized at 2000~2100℃ to obtain carbon fibers; the filament tension is controlled at 3.5~3.9 CN during the graphitization process; after cooling, the carbon fibers are washed with water, dried and wound up in sequence.

2. The carbon fiber reinforced ceramic matrix brake pad according to claim 1, characterized in that, The carbon fiber has a tensile strength ≥ 5700 MPa, strength CV ≤ 5%, elastic modulus ≥ 370 GPa, modulus CV ≤ 35%, and elongation at break ≥ 1.5%.

3. The carbon fiber reinforced ceramic matrix brake pad according to claim 1, characterized in that, The carbon fiber has a length of 5~10mm and a diameter of 8~15μm.

4. The carbon fiber reinforced ceramic matrix brake pad according to claim 1, characterized in that, The raw materials for this carbon fiber reinforced ceramic-based brake pad include the following components by weight: 3.7 parts zirconium oxide fiber, 7.5 parts nitrile rubber, 9.2 parts modified phenolic resin, 11 parts carbon fiber, 8.4 parts alumina fiber, 5.5 parts barite, 6.2 parts aramid fiber, 4.7 parts sepiolite, 6.9 parts ceramic fiber, 10.5 parts silicon carbide, 8.4 parts expanded vermiculite, 2.2 parts graphite, 2.7 parts corundum, and 9.6 parts zircon.

5. A carbon fiber reinforced ceramic-based brake pad according to claim 1, characterized in that, In step 1), the polyacrylonitrile precursor fiber has a strength ≥ 8.0 CN / dtex and a modulus ≥ 100 CN / dtex.

6. A carbon fiber reinforced ceramic-based brake pad according to claim 1, characterized in that, In step 1), the treatment reagent used for the oiling and stretching pretreatment is an aqueous solution of quaternary ammonium salt antistatic agent with a concentration of 0.05 wt%.

7. A carbon fiber reinforced ceramic matrix brake pad according to claim 1, characterized in that, In step 1), the draw ratio corresponding to the oiling and stretching pretreatment process is 0.15%, the monofilament tension of the fiber is controlled at 1.8 CN during the oiling and stretching pretreatment process, and the moisture content obtained after the oiling and stretching pretreatment is controlled at 16 wt% by the pressure roller.

8. A carbon fiber reinforced ceramic-based brake pad according to claim 1, characterized in that, In step 2), the ratio of the core diameter to the sheath diameter of the pre-oxidized fiber obtained by the pre-oxidation treatment is 0.

3.

9. A carbon fiber reinforced ceramic-based brake pad according to claim 1, characterized in that, Step 4) The high-temperature carbonized filaments obtained are controlled with a carbon fiber strength of 6200~6600MPa.

10. A carbon fiber reinforced ceramic matrix brake pad according to claim 1, characterized in that, The pre-oxidation treatment sequentially passes through the following temperature nodes: 190℃, 215℃, 228℃, 241℃, 250℃, and 260℃; the low-temperature carbonization treatment sequentially passes through the following temperature nodes: 360℃, 450℃, 550℃, 665℃, and 750℃; and the high-temperature carbonization treatment sequentially passes through the following temperature nodes: 1200℃, 1420℃, 1660℃, 1750℃, and 1520℃.

Images