Carbon-ceramic composite material and preparation method therefor, carbon-ceramic product, carbon-ceramic brake disc, and transportation vehicle

Abstract

The present application relates to a carbon-ceramic composite material and a preparation method therefor, a carbon-ceramic product, a carbon-ceramic brake disc, and a transportation vehicle. The preparation method for the carbon-ceramic composite material comprises the following steps: providing raw materials: chopped carbon fibers, a reinforcing material, carbon powder, and a binder, wherein the reinforcing material comprises at least one of a metal oxide and ground carbon fibers; and mixing the raw materials, and then sequentially performing molding treatment, carbonization treatment, and siliconizing treatment, so as to prepare the carbon-ceramic composite material.

Description

Carbon-ceramic composite materials, carbon-ceramic products and their preparation methods, carbon-ceramic brake discs and vehicles

[0001] Related applications

[0002] This application claims priority to Chinese patent application filed on December 16, 2024, with application number 202411847930.0, entitled "Carbon-ceramic composite material and preparation method thereof, carbon-ceramic brake disc and vehicle", the entire contents of which are incorporated herein by reference.

[0003] This application claims priority to Chinese patent application filed on December 13, 2024, with application number 202411834281.0 and entitled "Carbon ceramic articles and methods for preparing the same, and vehicles thereof", the entire contents of which are incorporated herein by reference. Technical Field

[0004] This application relates to the field of materials, and in particular to carbon-ceramic composite materials, carbon-ceramic products and their preparation methods, carbon-ceramic brake discs and vehicles. Background Technology

[0005] Carbon ceramic brake discs are made of carbon fiber reinforced silicon carbide composite materials. They are the third generation of brake materials developed after powder metallurgy brake discs. Compared with the most commonly used powder metallurgy brake discs, they have significant performance advantages: (1) Low density, which can effectively reduce the weight of the braking system. Carbon ceramic brake discs are about 50% lighter than powder metallurgy brake discs, which can reduce the weight of the car braking system by 10-20 kg; (2) Short braking distance. The friction coefficient of carbon ceramic brake discs is between 0.38 and 0.45, which is much higher than that of metal brake pads, greatly improving braking efficiency. Equipping a vehicle with carbon ceramic brake discs can reduce the braking distance from 100 km / h to less than 30 m. (3) High vehicle controllability; (4) High safety: Powder metallurgy brake discs will deform or even melt due to excessive temperature after continuous high-speed braking, resulting in safety accidents. Carbon ceramic brake discs are resistant to high temperature and can ensure normal use under high temperature conditions. At present, high-speed rail and civil aviation aircraft basically all use carbon ceramic brake systems; (5) Long service life: Carbon ceramic brake discs have low wear rate. Cast iron brake pads can be used for 80,000 to 100,000 km, while the service life of carbon ceramic brake discs can exceed 300,000 km; In addition, carbon ceramic brake discs also have high strength, good thermal conductivity, oxidation resistance and stable friction coefficient, making them ideal friction materials and widely used in aerospace and high-speed rail braking systems.

[0006] Carbon-ceramic brake discs are mainly divided into two types: long-fiber discs and short-fiber discs. Compared with long-fiber discs, short-fiber discs have the advantages of shorter manufacturing cycle and lower cost. However, traditional short-fiber discs have poor impact toughness.

[0007] Therefore, it is necessary to improve traditional technologies. Summary of the Invention

[0008] Based on this, this application provides a carbon-ceramic composite material with good impact resistance and toughness, carbon-ceramic products and their preparation methods, a carbon-ceramic brake disc and a vehicle.

[0009] The technical solution to the above-mentioned technical problems in this application is as follows.

[0010] This application provides a method for preparing a carbon-ceramic composite material, comprising the following steps:

[0011] Raw materials provided: chopped carbon fibers, reinforcing materials, carbon powder and binder, wherein the reinforcing materials include at least one of metal oxides and milled carbon fibers;

[0012] The raw materials are mixed and then subjected to molding, carbonization and silicon infiltration processes in sequence to prepare carbon-ceramic composite materials.

[0013] In some embodiments, the metal oxide in the preparation method of the carbon-ceramic composite material includes at least one of aluminum oxide, yttrium oxide, and zirconium oxide.

[0014] In some embodiments, the binder in the preparation method of the carbon-ceramic composite material includes at least one of phenolic resin and asphalt.

[0015] In some embodiments, the mass ratio of binder, carbon powder and reinforcing material in the preparation method of carbon-ceramic composite material is 20-35:10-35:0.5-15.

[0016] In some embodiments, the mass of chopped carbon fibers accounts for 30% to 60% of the total mass of the raw materials in the preparation method of carbon-ceramic composite materials.

[0017] In some embodiments, in the preparation method of carbon-ceramic composite material, the length of the milled carbon fiber is 200μm to 800μm, the aspect ratio of the milled carbon fiber is 30 to 70:1, and the mass of the milled carbon fiber accounts for 0% to 10% of the total mass of the raw materials.

[0018] In some embodiments, the preparation method of carbon-ceramic composite materials includes the following steps:

[0019] To prepare an intermediate mixture, the carbon powder, reinforcing materials and binder are mixed and then kneaded or mixed.

[0020] Short carbon fibers are mixed with intermediate blending materials.

[0021] This application provides a method for preparing a carbon-ceramic composite material, comprising the following steps:

[0022] Raw materials provided: chopped carbon fiber, milled carbon fiber, carbon powder and organic resin; wherein, the length of chopped carbon fiber is 8mm to 15mm, the length of milled carbon fiber is 200μm to 500μm, the aspect ratio of milled carbon fiber is 30 to 70:1, the mass of milled carbon fiber accounts for 3% to 8% of the total mass of raw materials, and the mass of chopped carbon fiber accounts for 40% to 60% of the total mass of raw materials;

[0023] The raw materials are mixed and molded to prepare carbon fiber composite materials;

[0024] Carbon-ceramic composite materials were prepared by sequentially carbonizing and siliconizing carbon fiber composite materials.

[0025] In some embodiments, the mass ratio of chopped carbon fiber, organic resin, carbon powder and milled carbon fiber in the preparation method of carbon-ceramic composite material is 40-60:20-30:10-30:3-8.

[0026] In some embodiments, the organic resin used in the preparation method of the carbon-ceramic composite material includes phenolic resin.

[0027] In some embodiments, the preparation method of carbon-ceramic composite material also includes additives, which include at least one of metal oxide powder and pore-forming agent.

[0028] In some embodiments, the mass ratio of additives to chopped carbon fibers in the preparation method of carbon-ceramic composite materials is 3-5:40-60.

[0029] This application provides a method for preparing carbon ceramic products, comprising the following steps:

[0030] To prepare an intermediate mixture, carbon powder, metal oxides, binders and additives are mixed and kneaded.

[0031] Short-cut carbon fibers are mixed with intermediate blends to prepare carbon fiber blends;

[0032] Carbon-ceramic composite materials were prepared by sequentially molding, carbonizing, and siliconizing carbon fiber mixtures.

[0033] In some embodiments, the mass ratio of binder, carbon powder, additives and metal oxide in the preparation method of carbon ceramic products is 25-35:10-30:3-5:0.5-2.

[0034] In some embodiments, the mass ratio of chopped carbon fibers to intermediate mixture in the preparation method of carbon ceramic products is 0.5 to 1.5:1.

[0035] In some embodiments, the binder in the method for preparing carbon ceramic products includes at least one of solid phenolic resin, asphalt, and liquid resin.

[0036] In some embodiments, the additives in the preparation method of carbon ceramic articles include pore-forming agents.

[0037] In some embodiments, the pore-forming agent in the preparation method of the carbon ceramic product includes at least one of ethylene glycol, PVB, and plant fiber powder.

[0038] In some embodiments, the mixing temperature is 60°C to 80°C and the mixing time is 10 min to 30 min in the method for preparing carbon-ceramic composite materials or carbon-ceramic products.

[0039] In some embodiments, the mixing temperature in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 120°C to 150°C, and the mixing time is 30 min to 120 min.

[0040] In some embodiments, in the method for preparing carbon-ceramic composite materials or carbon-ceramic products, the mixing temperature is 20°C to 35°C and the stirring speed is 10 r / min to 30 r / min during the step of mixing short-cut carbon fibers with intermediate mixture.

[0041] In some embodiments, in the method for preparing carbon-ceramic composite materials or carbon-ceramic products, the surface of the short-cut carbon fibers is provided with a sizing agent, which includes at least one of polyurethane and epoxy resin.

[0042] In some embodiments, the molding temperature in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 120°C to 200°C.

[0043] In some embodiments, the molding temperature in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 150°C to 200°C.

[0044] In some embodiments, the molding pressure in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 80 to 150 tons.

[0045] In some embodiments, the molding pressure in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 80 to 120 tons.

[0046] In some embodiments, the molding pressure in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 100 to 150 tons.

[0047] In some embodiments, the pressing time for molding treatment in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 20 min to 40 min.

[0048] In some embodiments, the preparation method of carbon-ceramic composite material or carbon-ceramic product uses a flat vulcanizing machine for molding.

[0049] In some embodiments, the carbonization temperature is 900℃~1200℃ and the carbonization time is 50h~70h in the method for preparing carbon-ceramic composite materials or carbon-ceramic products.

[0050] In some embodiments, the carbonization temperature in the method for preparing carbon-ceramic composite materials or carbon-ceramic products is 1000℃~1200℃.

[0051] In some embodiments, in the method for preparing carbon-ceramic composite materials or carbon-ceramic products, the silicon infiltration treatment temperature is 1500℃~1700℃ and the time is 3h~6h.

[0052] In some embodiments, the silicon infiltration treatment time in the preparation method of carbon-ceramic composite material or carbon-ceramic product is 3h to 5h.

[0053] In some embodiments, the method for preparing carbon-ceramic composite materials or carbon-ceramic products includes silicon infiltration treatment, which involves placing silicon sources on the upper and lower surfaces of the carbonized preform after carbonization treatment and performing silicon infiltration treatment in a silicon infiltration furnace.

[0054] In some embodiments, the silicon source in the method for preparing carbon-ceramic composite materials or carbon-ceramic products includes elemental silicon.

[0055] This application provides a carbon-ceramic composite material, which is prepared using the above-described method for preparing carbon-ceramic composite materials.

[0056] This application provides a carbon-ceramic brake disc, comprising the aforementioned carbon-ceramic composite material.

[0057] This application provides a carbon ceramic product, which is prepared using the above-described method for preparing carbon ceramic products.

[0058] In some embodiments, the carbon ceramic article includes a carbon ceramic brake disc.

[0059] This application provides a vehicle, including the aforementioned carbon-ceramic brake disc or the aforementioned carbon-ceramic product.

[0060] The method for preparing the carbon-ceramic composite material of this application includes mixing various raw materials and sequentially performing molding treatment, carbonization treatment and silicon infiltration treatment. The raw materials include chopped carbon fibers, reinforcing materials, carbon powder and binder. The reinforcing materials include at least one of metal oxides and milled carbon fibers. The carbon-ceramic composite material obtained has good flexural strength, tensile strength and impact toughness. Attached Figure Description

[0061] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the disclosed drawings without creative effort.

[0062] Figure 1 is a metallographic image of the carbon ceramic disc prepared in Experiment Example 1;

[0063] Figure 2 is a metallographic image of the carbon ceramic plate prepared in Experiment Example 9;

[0064] Figure 3 is a metallographic image of the carbon ceramic plate prepared in Experiment Example 13;

[0065] Figure 4 is a metallographic image of the carbon ceramic plate prepared in Experiment Example 14;

[0066] Figure 5 is a metallographic image of the carbon ceramic disc prepared in Experiment Example 16;

[0067] Figure 6 is a metallographic image of the carbon ceramic plate prepared in Experiment Example 17;

[0068] Figure 7 is a metallographic image of the carbon ceramic plate prepared in Experiment Example 18. Detailed Implementation

[0069] Reference will now be made to detailed embodiments of this application, one or more of which are described below. Each example is provided for explanation and not for limitation of this application. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to this application without departing from its scope or spirit. For example, features described or illustrated as part of one embodiment may be used in another embodiment to produce further embodiments.

[0070] Therefore, this application is intended to cover such modifications and variations falling within the scope of the appended claims and their equivalents. Other objects, features, and aspects of this application are disclosed in or will be apparent from the following detailed description. It will be understood by those skilled in the art that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of this application.

[0071] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0072] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element preceded by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The indefinite articles “a” and “an” preceding an element or component in this application are not restrictive in terms of the quantity (i.e., the number of times) of the element or component. Therefore, “an” or “a” should be interpreted as including one or at least one, and singular elements or components also include plural forms, unless the quantity clearly refers only to the singular. “A plurality” means at least two, such as two, three, etc., unless otherwise expressly specified.

[0073] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the weights mentioned in the embodiments of this application can be well-known units of mass in the chemical industry, such as μg, mg, g, and kg.

[0074] Unless otherwise shown or indicated in the operational embodiments, all figures used to represent the amounts, physicochemical properties, etc., of ingredients in the specification and claims are to be understood to be adjusted by the term "about" in all cases. For example, therefore, unless stated to the contrary, the numerical parameters listed in the foregoing specification and appended claims are approximations, and those skilled in the art can appropriately modify these approximations to obtain the desired characteristics by utilizing the teachings disclosed herein. The use of numerical ranges indicated by endpoints includes all numbers within that range and any range within that range; for example, 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4, and 5, etc.

[0075] One embodiment of this application provides a method for preparing a carbon-ceramic composite material, comprising the following steps:

[0076] Raw materials provided: chopped carbon fibers, reinforcing materials, carbon powder and binder, wherein the reinforcing materials include at least one of metal oxides and milled carbon fibers;

[0077] The raw materials are mixed and then subjected to molding, carbonization and silicon infiltration processes in sequence to prepare carbon-ceramic composite materials.

[0078] The preparation method of the above-mentioned carbon-ceramic composite material includes mixing the raw materials and sequentially performing molding treatment, carbonization treatment and silicon infiltration treatment. The raw materials include chopped carbon fibers, reinforcing materials, carbon powder and binder. The reinforcing materials include at least one of metal oxides and milled carbon fibers. The carbon-ceramic composite material obtained has good flexural strength, tensile strength and impact toughness.

[0079] In some of these examples, the metal oxides used in the preparation of carbon-ceramic composites include at least one of aluminum oxide, yttrium oxide, and zirconium oxide.

[0080] In some of these examples, the binder in the preparation method of the carbon-ceramic composite material includes at least one of phenolic resin and asphalt.

[0081] In some of these examples, the mass ratio of binder, carbon powder, and reinforcing material in the preparation method of carbon-ceramic composite materials is 20–35:10–35:0.5–15.

[0082] In some of these examples, the mass of chopped carbon fibers accounts for 30% to 60% of the total mass of the raw materials in the preparation method of carbon-ceramic composites.

[0083] In some of these examples, the preparation method of carbon-ceramic composite materials involves milled carbon fibers with a length of 200 μm to 800 μm, an aspect ratio of 30 to 70:1, and a mass of milled carbon fibers accounting for 0% to 10% of the total mass of the raw materials.

[0084] In some of these examples, the preparation method of carbon-ceramic composite materials includes the following steps in mixing the raw materials:

[0085] To prepare an intermediate mixture, the carbon powder, reinforcing materials and binder are mixed and then kneaded or mixed.

[0086] Short-cut carbon fibers are mixed with intermediate additives. One embodiment of this application provides a method for preparing a carbon-ceramic composite material, comprising the following steps:

[0087] Step S10: Provide raw materials: chopped carbon fiber, milled carbon fiber, carbon powder and organic resin; the length of chopped carbon fiber is 8mm to 15mm, the length of milled carbon fiber is 200μm to 500μm, the aspect ratio of milled carbon fiber is 30 to 70:1, the mass of milled carbon fiber accounts for 3% to 8% of the total mass of raw materials, and the mass of chopped carbon fiber accounts for 40% to 60% of the total mass of raw materials.

[0088] It is understood that the length of chopped carbon fibers includes, but is not limited to, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, and 15mm; the length of milled carbon fibers includes, but is not limited to, 200μm to 500μm; the aspect ratio of milled carbon fibers includes, but is not limited to, 30:1, 35:1, 40:1, 45:1, 50:1, 55:1, 60:1, 65:1, and 70:1; the percentage of the mass of milled carbon fibers to the total mass of the raw materials includes, but is not limited to, 3%, 4%, 5%, 6%, 7%, and 8%; the percentage of the mass of chopped carbon fibers to the total mass of the raw materials includes, but is not limited to, 40%, 42%, 45%, 48%, 50%, 52%, 55%, 58%, and 60%; in some examples, any two of these point values ​​can be used as end values ​​within a range, the same applies below.

[0089] In some of these examples, in step S10, the length of the chopped carbon fiber is 8 mm to 12 mm.

[0090] In some of these examples, in step S10, the length of the milled carbon fiber is 200 μm to 400 μm.

[0091] In some of these examples, in step S10, the aspect ratio of the milled carbon fiber is 50 to 70:1.

[0092] In some of these examples, in step S10, the mass of the pulverized carbon fiber accounts for 5% to 6% of the total mass of the raw material.

[0093] In some examples, in step S10, the mass of chopped carbon fibers accounts for 40% to 50% of the total mass of the raw materials.

[0094] Furthermore, the mass of chopped carbon fibers accounts for 40% to 45% of the total mass of the raw materials.

[0095] In some examples, in step S10, the mass ratio of chopped carbon fiber, organic resin, carbon powder and milled carbon fiber is 40-60:20-30:10-30:3-8.

[0096] It can be understood that the mass ratio of chopped carbon fiber to organic resin is 40-60:20-30 (i.e., the mass ratio of chopped carbon fiber to organic resin is 1.33-3:1), the mass ratio of chopped carbon fiber to carbon powder is 40-60:10-30 (i.e., the mass ratio of chopped carbon fiber to carbon powder is 1.33-6:1), and the mass ratio of chopped carbon fiber to milled carbon fiber is 40-60:5-10 (i.e., the mass ratio of chopped carbon fiber to milled carbon fiber is 4-12:1); further, it can be understood that the mass ratio of chopped carbon fiber to organic resin is 40-60:20-30 (i.e., the mass ratio of chopped carbon fiber to organic resin is 1.33-3:1), and the mass ratio of chopped carbon fiber to milled carbon fiber is 40-60:5-10 (i.e., the mass ratio of chopped carbon fiber to milled carbon fiber is 4-12:1); The mass ratio of organic resin includes, but is not limited to, 1.33:1, 1.5:1, 2:1, 2.5:1, and 3:1; the mass ratio of chopped carbon fiber to carbon powder includes, but is not limited to, 1.33:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, and 6:1; the mass ratio of chopped carbon fiber to milled carbon fiber includes, but is not limited to, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, and 12:1.

[0097] In some examples, in step S10, the mass ratio of chopped carbon fiber, organic resin, carbon powder and milled carbon fiber is 40-50:20-30:20-30:4-6.

[0098] In some examples, in step S10, the mass ratio of chopped carbon fiber, organic resin, carbon powder and milled carbon fiber is 40-45:20-25:22-28:4-6.

[0099] In some of these examples, in step S10, the organic resin includes phenolic resin.

[0100] In some of these examples, in step S10, the chopped carbon fibers are coated with a sizing agent, which includes at least one of polyurethane and epoxy resin.

[0101] In some of these examples, step S10, the preparation of chopped carbon fibers, includes the following steps:

[0102] The carbon fibers are first compressed and bundled, then surface slurry is cured, and then they are cut short.

[0103] Optionally, the sizing includes at least one of a polyurethane solution and an epoxy resin solution.

[0104] Furthermore, the mass concentrations of the polyurethane solution and the epoxy resin solution are independently 2% to 5%.

[0105] It is understood that the mass concentrations of the polyurethane solution and the epoxy resin solution are independently, but not limited to, 2%, 3%, 4%, and 5%.

[0106] Optionally, the carbon fiber includes, but is not limited to, T700 carbon fiber; further, the carbon fiber includes 24k or 12k.

[0107] In some of these examples, the pulverized carbon fiber is carbon fiber after the glue has been removed.

[0108] Degumming can be achieved by carbonizing carbon fibers at 600℃. Degumming reduces agglomeration of the ground carbon fibers, resulting in more uniform mixing in the material.

[0109] In some of these examples, step S10 also includes additives.

[0110] In some of these examples, the additives include at least one of metal oxide powder and pore-forming agent.

[0111] Furthermore, the metal oxide powder includes, but is not limited to, at least one of aluminum oxide, yttrium oxide, and zirconium oxide.

[0112] Adding specific types of metal oxide powder to raw materials can effectively improve the ceramic structure and enhance oxidation resistance.

[0113] Furthermore, the pore-forming agent includes, but is not limited to, at least one of ethylene glycol, PVB, and walnut flour plant fiber.

[0114] Adding a pore-forming agent to the raw materials improves the porosity after carbonization, facilitating ceramization.

[0115] In some of these examples, the mass ratio of additives to chopped carbon fibers is 3–5:40–60.

[0116] It can be understood that the mass ratio of additive to chopped carbon fiber is 1:8 to 20; further, it can be understood that the mass ratio of additive to chopped carbon fiber includes, but is not limited to, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, and 1:20.

[0117] In some of these examples, step S10 includes steps S11 to S12:

[0118] Step S11: The milled carbon fiber, carbon powder and organic resin are mixed for the first time to prepare a mixed powder.

[0119] In some examples, in step S11, the temperature of the first mixing is 25°C to 60°C, the rotation speed is 50 r / min to 300 r / min, and the time is 15 min to 60 min.

[0120] It is understood that the temperature of the first mixing is including but not limited to 25℃, 30℃, 35℃, 40℃, 45℃, 50℃, and 60℃, the rotation speed is including but not limited to 50r / min, 100r / min, 150r / min, 200r / min, and 300r / min, and the time is including but not limited to 15min, 20min, 25min, 30min, 45min, 50min, and 60min.

[0121] Step S12: Mix the mixed powder prepared in step S11 with the short-cut carbon fibers for a second time.

[0122] In some of these examples, in step S12, the temperature of the second mixing is 25°C to 60°C, the rotation speed is 80 r / min to 200 r / min, and the time is 15 min to 30 min.

[0123] It is understood that the temperature of the second mixing includes, but is not limited to, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, and 60°C; the rotation speed includes, but is not limited to, 80 r / min, 100 r / min, 150 r / min, and 200 r / min; and the time includes, but is not limited to, 15 min, 20 min, 25 min, and 30 min.

[0124] Step S20: Mix the raw materials and perform molding treatment to prepare carbon fiber composite material.

[0125] In some of these examples, the molding temperature in step S20 is 150°C to 200°C.

[0126] In some of these examples, step S20 involves molding using a flat vulcanizing machine.

[0127] In some of these examples, the pressure of the molding process in step S20 is 80 to 120 tons.

[0128] In some of these examples, the holding time for the molding process in step S20 is 20 min to 40 min.

[0129] It is understood that the molding temperature includes, but is not limited to, 150℃, 160℃, 170℃, 180℃, 190℃, and 200℃; the molding pressure includes, but is not limited to, 80 tons, 90 tons, 100 tons, 110 tons, and 120 tons; and the molding holding time includes, but is not limited to, 20 min, 22 min, 25 min, 28 min, 30 min, 32 min, 35 min, 38 min, and 40 min.

[0130] It is understandable that step S20, in the molding process, includes first preparing a blank, and then processing the blank into the required shape. For example, when the prepared carbon-ceramic composite material is a carbon-ceramic brake disc, it is processed into the basic shape of a carbon-ceramic brake disc, which includes deburring, processing heat dissipation holes on the disc surface, and processing side ventilation holes.

[0131] In some of these examples, the density of the carbon fiber composite is 1.3 g / cm³. 3 ~1.5g / cm 3 .

[0132] Step S30: Carbon fiber composite material is subjected to carbonization and silicon infiltration treatment in sequence to prepare carbon ceramic composite material.

[0133] The above-mentioned method for preparing carbon-ceramic composite materials involves mixing milled carbon fibers with chopped carbon fibers, carbon powder, and organic resin for molding. The length and aspect ratio of the milled carbon fibers, the length of the chopped carbon fibers, and the ratio of milled carbon fibers to chopped carbon fibers are controlled to ensure uniform distribution of the milled carbon fibers in the preform, effectively improving the bonding strength between the milled carbon fibers and other components. The carbon fiber composite material obtained in step S20 is then subjected to carbonization treatment, where the organic resin is carbonized into carbon, resulting in a short-fiber carbon fiber-reinforced carbon matrix composite material. The carbon matrix composite material after carbonization is then subjected to silicon infiltration treatment. The carbon and carbon powder produced after the organic resin carbonization react with molten silicon to form a silicon carbide matrix, while the milled carbon fibers react with molten silicon to form silicon carbide whiskers. The silicon carbide whiskers exhibit good bonding performance with the silicon carbide matrix, effectively improving the bending strength, tensile strength, and impact toughness of the carbon-ceramic brake disc.

[0134] In some of these examples, in step S30, the carbonization temperature is 900℃~1200℃ and the carbonization time is 60h~100h.

[0135] It is understood that the carbonization temperature includes, but is not limited to, 900℃, 1000℃, 1100℃, and 1200℃, and the carbonization time includes, but is not limited to, 60h, 70h, 80h, 90h, and 100h.

[0136] In some of these examples, in step S30, the silicon infiltration treatment is carried out at a temperature of 1500°C to 1700°C for 3 to 5 hours.

[0137] It is understood that the temperature of the silicon infiltration treatment includes, but is not limited to, 1500℃, 1520℃, 1550℃, 1580℃, 1600℃, 1620℃, 1650℃, 1680℃, and 1700℃, and the time includes, but is not limited to, 3h, 3.5h, 4h, 4.5h, and 5h.

[0138] In some examples, in step S30, the silicon diffusion process, the mass ratio of silicon to the carbonized preform after carbonization is 1.2 to 1.8:1.

[0139] It is understood that the mass ratio of silicon content to the carbonized preform after carbonization treatment includes, but is not limited to, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, and 1.8:1.

[0140] In some examples, in step S30, the silicon infiltration step, silicon is placed on the upper and lower surfaces of the carbide preform, and the mass ratio of silicon on the upper surface to silicon on the lower surface is 1:2 to 4.

[0141] In some of these examples, step S30, the silicon infiltration process includes the following steps:

[0142] The carbonized preform is placed in a silicon diffusion fixture, the surface of which is coated with boron nitride powder. A sheet of graphite paper is placed between the fixture and the carbonized preform. Silicon is added to the upper and lower surfaces of the carbonized preform, and it is placed in a silicon diffusion furnace for silicon diffusion treatment.

[0143] It is understandable that coating the tooling surface with boron nitride powder helps protect the tooling and reduces silicon corrosion.

[0144] In some examples, after step S30, a step of applying a protective coating to the surface of the workpiece after silicon infiltration is also included.

[0145] It is understood that protective coatings include, but are not limited to, anti-oxidation coatings and anti-corrosion coatings.

[0146] In some of these examples, applying a protective coating to the surface of a workpiece after silicon infiltration includes the following steps:

[0147] After siliconizing, the workpiece is immersed in a protective solution and then sintered to form a protective coating on the workpiece surface.

[0148] In some of these examples, the protective solution includes, but is not limited to, at least one of aluminum dihydrogen phosphate, aluminum chromium phosphate, boric acid, zirconium, nickel, strontium, and copper.

[0149] Applying an anti-oxidation coating to the surface of a workpiece after silicon infiltration treatment can prevent oxygen from reacting with carbon, silicon, and fibers, thereby increasing the lifespan of the brake disc, and is also inexpensive.

[0150] In some of these examples, the sintering temperature is 200°C to 300°C.

[0151] In some examples, the process also includes finishing steps on workpieces that have undergone silicon infiltration or have been coated with a protective coating.

[0152] The finishing process includes polishing the disc surface and creating through holes.

[0153] One embodiment of this application provides a carbon-ceramic composite material, which is prepared using the above-described method for preparing carbon-ceramic composite materials.

[0154] The carbon-ceramic composite material prepared by the above method exhibits high flexural strength, tensile strength, and impact toughness. It is understood that carbon-ceramic composite materials include, but are not limited to, brake discs.

[0155] In some of these examples, the carbon-ceramic composite material comprises silicon carbide whiskers.

[0156] One embodiment of this application provides a carbon-ceramic brake disc, comprising the aforementioned carbon-ceramic composite material.

[0157] It is understood that carbon-ceramic brake discs can be directly prepared using the aforementioned method for preparing carbon-ceramic composite materials. Specifically, one embodiment of this application provides a carbon-ceramic brake disc prepared using the aforementioned method for preparing carbon-ceramic composite materials.

[0158] The carbon-ceramic brake discs prepared by the above-mentioned method have high flexural strength, tensile strength and impact toughness, as well as good thermal conductivity, excellent thermal shock resistance and stable friction performance.

[0159] One embodiment of this application also provides a vehicle including the aforementioned carbon-ceramic brake disc.

[0160] It is understandable that means of transportation include, but are not limited to, automobiles.

[0161] One embodiment of this application provides a method for preparing carbon ceramic products, comprising the following steps:

[0162] Step S100: Mix the carbon powder, metal oxide, binder and additives and knead or mix them to prepare an intermediate mixture.

[0163] In some of these examples, in step S100, the mass ratio of binder, toner, additives and metal oxide is 25-35:10-30:3-5:0.5-2.

[0164] It is understandable that the mass ratio of binder to toner is 25-35:10-30; the mass ratio of additive to toner is 3-5:10-30; and the mass ratio of metal oxide to toner is 0.5-2:10-30.

[0165] Optionally, the mass ratio of binder, toner, additives and metal oxide is 25-30:15-20:3-4:1-2.

[0166] Furthermore, the mass ratio of binder, toner, additives and metal oxide is 28-30:18-20:3-4:1-2.

[0167] In some of these examples, in step S100, the binder includes at least one of solid phenolic resin, bitumen, and liquid resin.

[0168] In some of these examples, in step S100, the metal oxide includes at least one of aluminum oxide, yttrium oxide, and zirconium oxide.

[0169] In some of these examples, in step S100, the additive includes a pore-forming agent.

[0170] Furthermore, the pore-forming agent includes, but is not limited to, at least one of ethylene glycol, PVB, and plant fiber powder.

[0171] It can be understood that step S100 includes either step S110 or step S120:

[0172] Step S110: Mix carbon powder, metal oxide, binder and additives and knead them to prepare intermediate mixture.

[0173] In some of these examples, in step S110, the mixing temperature is 60°C to 80°C and the time is 10 min to 30 min.

[0174] It can be understood that the mixing temperature refers to the set temperature of the internal mixer; further, the mixing temperature includes, but is not limited to, 60℃, 62℃, 65℃, 68℃, 70℃, 72℃, 75℃, 78℃, and 80℃, and the time includes, but is not limited to, 10min, 12min, 15min, 18min, 20min, 22min, 25min, 28min, and 30min. In some examples, any two of these point values ​​can be used as endpoints within a range, and the same applies below.

[0175] In some of these examples, in step S110, the binder comprises a solid phenolic resin.

[0176] In some of these examples, in step S110, a three-dimensional mixer is used to mix the toner, metal oxide, binder, and additives.

[0177] In some examples, after step S110 and before step S200, a step of crushing the intermediate mixture prepared in step S110 is included. Further, the particle size of the crushed intermediate mixture is 3 mm to 5 mm.

[0178] Step S120: Mix and knead the toner, metal oxide, binder and additives to prepare an intermediate mixture.

[0179] It is understood that in step S120, the binder is a liquid binder. Further, the liquid binder includes at least one of asphalt and a liquid resin. Further, the liquid resin includes a liquid phenolic resin. Further, the binder includes asphalt.

[0180] In some of these examples, in step S120, the kneading temperature is 120°C to 150°C and the time is 30 min to 120 min.

[0181] It can be understood that the kneading temperature refers to the set temperature of the kneading machine; further, the kneading temperature includes, but is not limited to, 120℃, 130℃, 140℃, and 150℃, and the time includes, but is not limited to, 30min, 50min, 80min, 100min, and 120min.

[0182] In some examples, step S120 includes step S1210: mixing and preheating the toner, metal oxide and additives, and then mixing and kneading the mixture obtained from mixing and preheating with a liquid binder.

[0183] In some of these examples, in step S1210, toner, metal oxide and additives are placed in a kneader for preheating and kneading, and then a liquid binder is added and kneaded.

[0184] In some of these examples, step S120 includes step S1220:

[0185] Carbon powder, metal oxides and additives are mixed and preheated, and then the mixture obtained from the mixing and preheating is mixed with asphalt and kneaded.

[0186] In some of these examples, in step S1220, carbon powder, metal oxides and additives are placed in a kneader for preheating and kneading, and then liquid asphalt is added and kneaded.

[0187] In some of these examples, in step S1220, the set temperature of the kneader is 140℃~150℃, and the preheating kneading time is 40min~80min.

[0188] It is understandable that liquid asphalt can be melted by placing it at a temperature above its melting point.

[0189] In some of these examples, step S120 includes step S1230:

[0190] The toner, metal oxides and additives are mixed and preheated, and then the mixture obtained from the mixing and preheating is mixed with liquid phenolic resin and kneaded.

[0191] In some of these examples, in step S1230, toner, metal oxide and additives are placed in a kneader for preheating and kneading, and then liquid phenolic resin is added for further kneading.

[0192] Furthermore, in step S1230, the temperature of the kneader is set to 60℃~80℃, and the preheating and kneading time is 20min~40min.

[0193] Step S200: Mix the short-cut carbon fibers with the intermediate mixture to prepare the carbon fiber mixture.

[0194] In some examples, in step S200, the mass ratio of chopped carbon fibers to intermediate blend is 0.5 to 1.5:1.

[0195] It is understood that the mass ratio of chopped carbon fiber to intermediate blending is including but not limited to 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, and 1.5:1.

[0196] Optionally, in step S200, the mass ratio of chopped carbon fiber to intermediate mixture is 1 to 1.5:1.

[0197] In some examples, in step S200, the mixing temperature is 20°C to 35°C, and the stirring speed is 10 r / min to 30 r / min.

[0198] It is understood that mixing is carried out at room temperature, and the stirring speed includes, but is not limited to, 10 r / min, 12 r / min, 15 r / min, 18 r / min, 20 r / min, 22 r / min, 25 r / min, 28 r / min, and 30 r / min.

[0199] In some of these examples, in step S200, the mixture is stirred in a high-speed mixer.

[0200] In some of these examples, in step S200, the length of the chopped carbon fiber is 8 mm to 15 mm.

[0201] It is understood that the length of chopped carbon fiber includes, but is not limited to, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, and 15mm.

[0202] In some of these examples, in step S200, the sides of the chopped carbon fibers are provided with a modifying material, which includes at least one of polyurethane and epoxy resin.

[0203] In some of these examples, step S200, the preparation of chopped carbon fibers includes the following steps:

[0204] The carbon fibers are first compressed and bundled, then surface slurry is cured, and then they are cut short.

[0205] Optionally, the sizing includes at least one of a polyurethane solution and an epoxy resin solution.

[0206] Furthermore, the mass concentrations of the polyurethane solution and the epoxy resin solution are independently 2% to 5%.

[0207] It is understood that the mass concentrations of the polyurethane solution and the epoxy resin solution are independently, but not limited to, 2%, 3%, 4%, and 5%.

[0208] Optionally, the carbon fiber includes, but is not limited to, T700 carbon fiber; further, the carbon fiber includes 24k or 12k.

[0209] Step S300: The carbon fiber mixture is subjected to molding, carbonization and silicon infiltration processes in sequence to prepare carbon ceramic products.

[0210] By first mixing carbon powder, metal oxides, binders, and additives and then kneading or mixing them, the binder is evenly coated on the surface of the carbon powder and other powder raw materials, which can prevent the carbon powder and other powder raw materials from agglomerating with the binder. Then, the prepared intermediate mixture is mixed with chopped carbon fibers. The binder coated on the surface of the powder has good bonding performance with the chopped carbon fibers, which can effectively improve the bonding force between the chopped carbon fibers and the powder, and prevent the powder and chopped carbon fibers from delaminating. This improves the uniformity of the preform obtained after molding, and further improves the impact toughness and tensile strength of the carbon ceramic products obtained after carbonization and silicon infiltration treatment, while also ensuring that the flexural strength and compressive strength of the carbon ceramic products are also high.

[0211] If short-cut carbon fibers are simultaneously mixed or kneaded with carbon powder, metal oxides, binders and additives, the improvement in tensile strength and impact toughness will be very limited. This is believed to be because the short-cut carbon fibers are damaged during the mixing or kneading process.

[0212] It is understandable that molding process forms a preform, carbonization process forms a carbonized preform, and silicon infiltration process forms a carbon ceramic material.

[0213] In some of these examples, the molding temperature in step S300 is 120°C to 200°C.

[0214] In some of these examples, the pressure of the molding process in step S300 is 100 to 150 tons.

[0215] In some of these examples, the holding time for the molding process in step S300 is 20 min to 40 min.

[0216] It is understood that the molding temperature includes, but is not limited to, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, and 200℃; the molding pressure includes, but is not limited to, 100 tons, 110 tons, 120 tons, 130 tons, 140 tons, and 150 tons; and the molding holding time includes, but is not limited to, 20 min, 22 min, 25 min, 28 min, 30 min, 32 min, 35 min, 38 min, and 40 min.

[0217] In some of these examples, in step S300, compression molding is performed under a flat vulcanizing machine.

[0218] It is understandable that step S300, in the forming process, includes first preparing a blank, and then processing the blank into the desired shape. For example, when the prepared carbon-ceramic product is a carbon-ceramic brake disc, it is processed into the basic shape of a carbon-ceramic brake disc.

[0219] Processing the blank into a brake disc shape is more convenient, efficient, and cost-effective than processing a silicon carbide blank.

[0220] In some of these examples, in step S300, the density of the preform formed by the molding process is 1.25 g / cm³. 3 ~1.5g / cm 3 .

[0221] In some examples, in step S300, the carbonization temperature is 1000℃~1200℃ and the carbonization time is 50h~70h.

[0222] In some examples, in step S300, the temperature of the silicon diffusion treatment is 1500℃~1700℃, and the time of the silicon diffusion treatment is 3h~6h.

[0223] It is understood that the temperature of the silicon infiltration treatment includes, but is not limited to, 1500℃, 1520℃, 1550℃, 1580℃, 1600℃, 1620℃, 1650℃, 1680℃, and 1700℃, and the time of the silicon infiltration treatment includes, but is not limited to, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, and 6h.

[0224] In some examples, in step S300, during the silicon infiltration process, the mass ratio of silicon to the carbonized preform after carbonization is 1.2 to 1.8:1.

[0225] It is understood that the mass ratio of silicon content to the carbonized preform after carbonization treatment includes, but is not limited to, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, and 1.8:1.

[0226] In some examples, in step S300, during the silicon infiltration process, silicon is placed on the upper and lower surfaces of the carbide preform, with the mass ratio of silicon on the upper surface to silicon on the lower surface being 1:2 to 4.

[0227] In some examples, step S300 includes: placing silicon sources on the upper and lower surfaces of the carbonized preform after carbonization, and performing silicon infiltration in a silicon infiltration furnace.

[0228] Optionally, the silicon source may include, but is not limited to, elemental silicon.

[0229] In some of these examples, step S300, the silicon infiltration process includes the following steps:

[0230] The carbonized preform is placed in a silicon diffusion fixture, the surface of which is coated with boron nitride powder. A sheet of graphite paper is placed between the fixture and the carbonized preform. Silicon is added to the upper and lower surfaces of the carbonized preform, and it is placed in a silicon diffusion furnace for silicon diffusion treatment.

[0231] It is understandable that coating the tooling surface with boron nitride powder helps protect the tooling and reduces silicon corrosion.

[0232] In some examples, after step S300, a step of applying a protective coating to the surface of the workpiece after silicon infiltration is also included.

[0233] It is understood that protective coatings include, but are not limited to, anti-oxidation coatings and anti-corrosion coatings.

[0234] In some of these examples, applying a protective coating to the surface of a workpiece after silicon infiltration includes the following steps:

[0235] After siliconizing, the workpiece is immersed in a protective solution and then sintered to form a protective coating on the workpiece surface.

[0236] In some of these examples, the protective solution includes, but is not limited to, at least one of aluminum dihydrogen phosphate, aluminum chromium phosphate, boric acid, zirconium, nickel, strontium, and copper.

[0237] Applying an anti-oxidation coating to the surface of a workpiece after silicon infiltration treatment can prevent oxygen from reacting with carbon, silicon, and fibers, thereby increasing the lifespan of the brake disc, and is also inexpensive.

[0238] In some of these examples, the sintering temperature is 200°C to 300°C.

[0239] In some examples, the process also includes finishing steps on workpieces that have undergone silicon infiltration or have been coated with a protective coating.

[0240] The finishing process includes polishing the disc surface and creating through holes.

[0241] One embodiment of this application provides a carbon ceramic product, which is prepared using the above-described method for preparing carbon ceramic products.

[0242] The carbon ceramic products prepared by the above method have high impact toughness and tensile strength, as well as high bending strength and compressive strength.

[0243] It is understandable that carbon ceramic products include, but are not limited to, brake discs.

[0244] It is understood that one embodiment of this application provides a carbon-ceramic brake disc, which is prepared using the above-described method for preparing carbon-ceramic products.

[0245] The carbon-ceramic brake discs prepared by the above-mentioned method have high impact toughness and tensile strength, as well as high bending strength and compressive strength, good thermal conductivity, excellent thermal shock resistance, and stable friction performance.

[0246] One embodiment of this application also provides a vehicle including the aforementioned carbon-ceramic brake disc.

[0247] It is understandable that means of transportation include, but are not limited to, automobiles.

[0248] It is understood that when the above-mentioned method for preparing carbon-ceramic composite materials is directly used to prepare carbon-ceramic products, it can essentially be considered as a method for preparing carbon-ceramic products. The above-mentioned method for preparing carbon-ceramic composite materials and the above-mentioned characteristics of carbon-ceramic products can be used in a mutually compatible manner.

[0249] One embodiment of this application provides a carbon-ceramic composite material, which is prepared using the above-described method for preparing carbon-ceramic composite materials.

[0250] The carbon-ceramic composite material prepared by the above method exhibits high flexural strength, tensile strength, and impact toughness. It is understood that carbon-ceramic composite materials include, but are not limited to, brake discs.

[0251] In some of these examples, the carbon-ceramic composite material comprises silicon carbide whiskers.

[0252] One embodiment of this application provides a carbon-ceramic brake disc, comprising the aforementioned carbon-ceramic composite material.

[0253] It is understood that carbon-ceramic brake discs can be directly prepared using the aforementioned method for preparing carbon-ceramic composite materials. Specifically, one embodiment of this application provides a carbon-ceramic brake disc prepared using the aforementioned method for preparing carbon-ceramic composite materials.

[0254] The carbon-ceramic brake discs prepared by the above-mentioned method have high flexural strength, tensile strength and impact toughness, as well as good thermal conductivity, excellent thermal shock resistance and stable friction performance.

[0255] One embodiment of this application provides a carbon ceramic product, which is prepared using the above-described method for preparing carbon ceramic products.

[0256] The carbon ceramic products prepared by the above method have high impact toughness and tensile strength, as well as high bending strength and compressive strength.

[0257] It is understandable that carbon ceramic products include, but are not limited to, brake discs.

[0258] It is understood that one embodiment of this application provides a carbon-ceramic brake disc, which is prepared using the above-described method for preparing carbon-ceramic products.

[0259] The carbon-ceramic brake discs prepared by the above-mentioned method have high impact toughness and tensile strength, as well as high bending strength and compressive strength, good thermal conductivity, excellent thermal shock resistance, and stable friction performance.

[0260] One embodiment of this application also provides a vehicle, including the above-described carbon ceramic brake disc or the above-described carbon ceramic product.

[0261] It is understandable that means of transportation include, but are not limited to, automobiles.

[0262] The present application will be described in further detail below with reference to specific embodiments, but the embodiments of the present application are not limited thereto.

[0263] Experimental Example 1

[0264] S1. Raw material mixing: The raw materials include short-cut carbon fibers (12K T700 grade sized carbon fibers, the slurry being a PU solution with a solid content of 2% to 4%), solid phenolic resin, carbon powder, metal oxides (alumina and yttrium oxide in a mass ratio of 1:1) and milled carbon fibers in a mass ratio of 40:25:25:5:5; wherein, the length of the short-cut carbon fibers is 10mm, the length of the milled carbon fibers is 200μm, the aspect ratio of the milled carbon fibers is 70:1, and the mass of the milled carbon fibers accounts for 5% of the total mass of the raw materials;

[0265] Solid phenolic resin, carbon powder, metal oxide and milled carbon fiber are thoroughly mixed at 30℃ and 100r / min for 30min to obtain a mixed powder; then the mixed powder is thoroughly mixed with chopped carbon fiber at 30℃ and 100r / min for 30min to obtain a mixture.

[0266] S2. Compression Molding: The mixture prepared in step S1 is poured into the mold, ensuring even distribution. The mold cover is then closed, and the mold is placed under a flat vulcanizing machine with a pressing pressure of 200 tons. The pressure is 120 tons, the mold temperature is 180℃, and the pressure is maintained for 30 minutes for curing. After curing, the mold is removed, cooled in cold water, and then the mold is opened and the material is extracted to obtain a carbon fiber reinforced resin matrix composite preform with a density of 1.5 g / cm³. 3 ;

[0267] S3. Blank processing: The blank prepared in step S2 is machined to obtain a carbon ceramic brake disc blank, including deburring, processing of heat dissipation holes on the disc surface, and processing of side ventilation holes.

[0268] S4. Carbonization: The carbon ceramic brake disc blank prepared in step S3 is carbonized in a carbonization furnace at a carbonization temperature of 1000℃ for 60h to obtain a carbonized blank.

[0269] S5. Ceramization: The carbonized preform prepared in step S4 is placed in a silicon infiltration fixture. Boron nitride powder is coated on the surface of the fixture. A piece of graphite paper is added between the fixture and the carbonized preform. Silicon particles are added to the upper and lower surfaces of the carbonized preform. The mass ratio of silicon particles to carbonized preform is 1.5:1, and the mass ratio of silicon particles on the upper surface to the lower surface of the carbonized preform is 1:3. The fixture and preform are placed in a special silicon infiltration furnace and silicon infiltrated at 1600℃~1700℃ for 3h~5h to obtain a ceramized preform.

[0270] S6. Finishing: Polishing, drilling through holes, and machining assembly holes on the surface of the ceramic blank prepared in step S5, and completing the subsequent assembly and testing processes to produce the finished carbon ceramic disc.

[0271] The metallographic image of the carbon ceramic disc prepared in Experiment Example 1 is shown in Figure 1. Short-cut carbon fiber 100 and ground carbon fiber 200 of different lengths can be seen.

[0272] Experiment Example 2

[0273] The experiment was basically the same as in Example 1, except that the length of the ground carbon fiber was 500 μm.

[0274] Experimental Example 3

[0275] The experiment was basically the same as in Experiment 1, except that the milled carbon fibers were first milled carbon fibers and second milled carbon fibers with a mass ratio of 1:1. The length of the first milled carbon fiber was 200 μm and the length of the second milled carbon fiber was 500 μm.

[0276] Experiment Example 4

[0277] The experiment was basically the same as in Example 1, except that the mass ratio of short-cut carbon fiber, solid phenolic resin, carbon powder, metal oxide and milled carbon fiber in the raw materials was 50:25:15:5:5, the mass of milled carbon fiber accounted for 5% of the total mass of the raw materials, and the mass of short-cut carbon fiber accounted for 50% of the total mass of the raw materials.

[0278] Experimental Example 5

[0279] The experiment was basically the same as in Experiment 1, except that the mass ratio of short-cut carbon fiber, solid phenolic resin, carbon powder, additives and milled carbon fiber in the raw materials was 45:25:25:5:0, that is, no milled fiber was added.

[0280] Experimental Example 6

[0281] The experiment was basically the same as in Experiment 1, except that the mass ratio of short-cut carbon fiber, solid phenolic resin, carbon powder, metal oxide and milled carbon fiber in the raw materials was 35:25:25:5:10, and the mass of milled carbon fiber accounted for 10% of the total mass of the raw materials.

[0282] Experimental Example 7

[0283] The experiment was basically the same as in Experiment 1, except that the mass ratio of short-cut carbon fiber, solid phenolic resin, carbon powder, metal oxide and milled carbon fiber in the raw materials was 30:25:35:5:5, the mass of milled carbon fiber accounted for 5% of the total mass of the raw materials, and the mass of short-cut carbon fiber accounted for 30% of the total mass of the raw materials.

[0284] Experimental Example 8

[0285] The experiment was basically the same as in Example 1, except that the length of the milled carbon fiber was 800 μm.

[0286] Samples of the carbon ceramic discs prepared in Examples 1 to 8 were taken and tested for bending strength, impact toughness and tensile strength according to the T / CAAMTB 09-2019 Passenger Car Brake Disc Product Standard and Test Method. The average test results are shown in Table 1.

[0287] Table 1

[0288] Table 1 shows that the carbon ceramic discs prepared in the experimental examples exhibit significantly improved flexural strength, tensile strength, and impact toughness. Longer milled fibers demonstrate better tensile strength, while shorter milled fibers improve flexural strength and impact toughness. Combining milled carbon fibers of different lengths further enhances the overall performance of the material. Specifically, in Experiments 6 and 7, adjusting the ratio of milled or chopped carbon fibers resulted in lower impact toughness compared to Experiments 1–4. In Experiment 8, adjusting the length of the milled carbon fibers resulted in overall performance inferior to Experiments 1–4.

[0289] Analysis suggests that the significant density difference between carbon fiber and other powders such as resin and carbon powder makes mixing prone to resin and carbon powder agglomeration and material stratification, resulting in large performance differences in different areas. The lack of resin in some areas can easily lead to product defects. After carbonization and silicon infiltration, the distribution of fiber reinforcement phase and silicon carbide matrix becomes uneven. In particular, the impact toughness and tensile strength of the silicon carbide matrix are low, resulting in low overall brake disc performance or product defects.

[0290] Experimental Example 9

[0291] S1. The binder (solid phenolic resin), toner, pore-forming agent (PVB) and metal oxide (alumina and yttrium oxide in a mass ratio of 1:1) are premixed evenly in a mass ratio of 25:20:3:2. The mixture is then placed in an internal mixer and kneaded at a temperature of 60°C and a speed of 10 r / min to 30 r / min until the mixing temperature is higher than 85°C (about 15 min). The mixture is then discharged, crushed, and sieved through a 40-mesh sieve to obtain an intermediate mixture.

[0292] S2. Short carbon fibers (12K T700 grade sized carbon fibers, the slurry is a PU solution with a solid content of 2% to 4%, and the length is 8mm) are mixed with the intermediate mixture prepared in step S1 at a mass ratio of 1:1 in a high-speed mixer at a rotation speed of 20r / min at room temperature to obtain carbon fiber mixture.

[0293] S3. Compression Molding: The carbon fiber mixture prepared in step S2 is poured into a mold, ensuring even distribution. The mold cover is then closed, and the mold is placed under a flat vulcanizing machine with a pressing pressure of 200 tons. The pressure is 120 tons, the mold temperature is 180℃, and the pressure is maintained for 30 minutes for curing. After curing, the mold is removed, cooled in cold water, and then the mold is opened to obtain the preform with a density of 1.4 g / cm³. 3 ;

[0294] S4. Blank processing: The blank prepared in step S3 is machined to obtain a carbon ceramic brake disc blank, including deburring, processing of heat dissipation holes on the disc surface, and processing of side ventilation holes.

[0295] S5. Carbonization: The carbon ceramic brake disc blank prepared in step S4 is carbonized in a carbonization furnace. The maximum carbonization temperature is 1200℃ and the total carbonization time is 60h to obtain a carbonized blank.

[0296] S6. Ceramization: The carbonized preform prepared in step S5 is placed in a silicon infiltration fixture. Boron nitride powder is coated on the surface of the fixture. A piece of graphite paper is added between the fixture and the carbonized preform. Silicon particles are added to the upper and lower surfaces of the carbonized preform. The mass ratio of silicon particles to carbonized preform is 1.5:1, and the mass ratio of silicon particles on the upper surface to the lower surface of the carbonized preform is 1:3. The fixture and preform are placed in a special silicon infiltration furnace and silicon infiltrated at 1600℃~1700℃ for 3h~5h to obtain a ceramized preform.

[0297] S7. Finishing: Polishing, drilling through holes, and machining assembly holes on the surface of the ceramic blank prepared in step S6, and completing the subsequent assembly and testing processes to produce the finished carbon ceramic disc.

[0298] Experimental Example 10

[0299] It is basically the same as Experiment 9, except that in step S1, the mixing temperature is 65℃.

[0300] Experimental Example 11

[0301] It is basically the same as Experiment 9, except that in step S1, the mixing temperature is 70℃.

[0302] Experimental Example 12

[0303] It is basically the same as Experimental Example 9, except that in step S2, the mass ratio of chopped carbon fiber to intermediate mixture is 0.8:1.

[0304] Experimental Example 13

[0305] S1. Prepare binder asphalt, carbon powder, pore-forming agent (PVB), and metal oxide (alumina) in a mass ratio of 30:15:3:2. Place the carbon powder, pore-forming agent, and metal oxide in a kneader and preheat and knead for 60 minutes at a kneader temperature of 150°C. Melt the asphalt at 160°C and add it to the kneader and knead until the paste temperature rises to 190°C. Discharge the material, crush it into powder, and obtain the intermediate mixture.

[0306] S2. Short carbon fibers (12K T700 grade sized carbon fibers, the slurry is a PU solution with a solid content of 2% to 4%, and the length is 8mm) are mixed with the intermediate mixture prepared in step S1 at a mass ratio of 1:1 in a high-speed mixer at a rotation speed of 20r / min at room temperature to obtain carbon fiber mixture.

[0307] The carbon fiber mixture was subjected to molding, preform processing, carbonization, ceramization and finishing in sequence according to steps S3 to S7 of Experiment Example 9 to prepare the finished carbon ceramic plate.

[0308] Experimental Example 14

[0309] S1. Prepare a binder (liquid phenolic resin), toner, pore-forming agent (PVB), and metal oxide in a mass ratio of 35:20:3:2. Place the toner, pore-forming agent, and metal oxide in a kneader and preheat and knead for 10 minutes at a kneader temperature of 70°C. Add the liquid phenolic resin and knead for 30 minutes. Discharge the mixture to obtain an intermediate mixture.

[0310] S2. Short carbon fibers (12K T700 grade sized carbon fibers, the slurry is a PU solution with a solid content of 2% to 4%, and the length is 8mm) are mixed with the intermediate mixture prepared in step S1 at a mass ratio of 1:1 in a high-speed mixer at a temperature of 120℃ and a rotation speed of 20 rpm to obtain carbon fiber mixture.

[0311] The carbon fiber mixture was subjected to molding, preform processing, carbonization, ceramization and finishing in sequence according to steps S3 to S7 of Experiment Example 9 to prepare the finished carbon ceramic plate.

[0312] Experimental Example 15

[0313] It is basically the same as Experiment 13, except that in step S1, the temperature of the kneader is 120℃.

[0314] Experimental Example 16

[0315] This is basically the same as Example 9, except that steps S1 to S2 in Example 9 are replaced with the following steps:

[0316] Short carbon fibers (12K T700 grade sized carbon fibers, the slurry is a PU solution with a solid content of 2% to 4%, and the length is 8mm), binder (solid phenolic resin), carbon powder, pore-forming agent (PVB) and metal oxides are mixed evenly in a high-speed mixer at a mass ratio of 50:25:20:3:2 and a rotation speed of 20r / min at room temperature to obtain carbon fiber mixture;

[0317] The carbon fiber mixture was subjected to molding, preform processing, carbonization, ceramization and finishing in sequence according to steps S3 to S7 of Experiment Example 9 to prepare the finished carbon ceramic plate.

[0318] Experimental Example 17

[0319] This is basically the same as Example 9, except that steps S1 to S2 in Example 9 are replaced with the following steps:

[0320] Short carbon fibers (12K T700 grade sized carbon fibers, the slurry being a PU solution with a solid content of 2% to 4%, and a length of 8mm), binder (solid phenolic resin), carbon powder, pore-forming agent (PVB), and metal oxides are placed in an internal mixer at a mass ratio of 50:25:20:3:2 and mixed at a mixing temperature of 60℃ and a rotation speed of 10r / min to 30r / min until the mixing temperature is higher than 85℃ (about 15min). The material is then discharged and crushed to obtain a carbon fiber mixture.

[0321] The carbon fiber mixture was subjected to molding, preform processing, carbonization, ceramization and finishing in sequence according to steps S3 to S7 of Experiment Example 9 to prepare the finished carbon ceramic plate.

[0322] Experiment 18

[0323] This is basically the same as Experiment 14, except that steps S1 to S2 in Experiment 18 are replaced with the following steps:

[0324] Prepare short-cut carbon fibers (12K T700 grade sized carbon fibers, sizing agent is PU solution with solid content of 2% to 4%, length 8mm) with a mass ratio of 60:35:20:3:2, binder (liquid phenolic resin), carbon powder, pore-forming agent and metal oxide. Place the short-cut carbon fibers, carbon powder, pore-forming agent and metal oxide in a kneader and preheat and knead for 10 minutes at a kneader temperature of 70℃. Add liquid phenolic resin and knead for 30 minutes. Discharge to obtain carbon fiber mixture.

[0325] The carbon fiber mixture was subjected to molding, preform processing, carbonization, ceramization and finishing in sequence according to steps S3 to S7 of Experiment Example 9 to prepare the finished carbon ceramic plate.

[0326] The metallographic image of the carbon ceramic plate prepared in Experiment 9 is shown in Figure 2. The metallographic image of the carbon ceramic plate prepared in Experiment 13 is shown in Figure 3. The metallographic image of the carbon ceramic plate prepared in Experiment 14 is shown in Figure 4. The metallographic image of the carbon ceramic plate prepared in Experiment 16 is shown in Figure 5. The metallographic image of the carbon ceramic plate prepared in Experiment 17 is shown in Figure 6. The metallographic image of the carbon ceramic plate prepared in Experiment 18 is shown in Figure 7.

[0327] Figures 2-4 show the metallographic images of the carbon-ceramic brake disc material. The fiber bundles are relatively intact and evenly distributed within the silicon carbide matrix, indicating relatively high material strength. Figure 5 also shows relatively intact fibers, but large sections of the silicon carbide matrix lack fiber reinforcement, and the bonding performance with the fibers is poor. In Figures 6 and 7, the fibers are evenly distributed within the silicon carbide matrix, but the fiber bundle structure is disrupted, resulting in lower material strength.

[0328] The density and porosity of the finished carbon ceramic discs were measured using the water displacement method. The required density was (2.2 ± 0.1 g / cm³).3 ) and porosity (≤10%).

[0329] The tensile strength, flexural strength, compressive strength, and impact toughness of the samples were tested using an electronic universal testing machine.

[0330] Tensile strength test specimen dimensions (dumbbell-shaped specimen): 120mm*18mm*4mm;

[0331] Bending strength test specimen dimensions: 55mm*10mm*4mm;

[0332] Compressive strength: 10mm*10mm*10mm;

[0333] Impact toughness specimen size: 55mm*10mm*10mm.

[0334] Brake disc simulated bench test:

[0335] The JF122 series automotive brake inertial test bench of Jilin Jida Electromechanical Equipment Co., Ltd. was used to conduct simulated braking tests on the finished carbon ceramic disc of the test example. The test was based on the SAE J2522 standard. This standard includes performance testing of various aspects of the brake disc and is based on the structure, demonstration and some definitions of the current European AK Master test method version.

[0336] The test results of Experiments 9-18 are shown in Table 2.

[0337] Table 2

[0338] As shown in Table 2, compared with the carbon ceramic discs prepared in Example 16, the carbon ceramic discs prepared in Examples 9-15 exhibit significantly improved tensile strength, flexural strength, and impact toughness while maintaining density, porosity, and coefficient of friction. This indicates that the present application's method of first mixing carbon powder, metal oxides, binders, and additives through intensive mixing or kneading, and then mixing the prepared intermediate mixture with chopped carbon fibers, can solve problems such as the separation of light and heavy powders during the mixing process, while simultaneously improving the bonding force between the chopped carbon fibers and the powder. In Examples 17 and 18, the chopped fibers were directly intensively mixed or kneaded with other components simultaneously, resulting in lower tensile strength and impact toughness compared to Examples 9-15.

[0339] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0340] The embodiments described above are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A method for preparing a carbon-ceramic composite material, comprising the following steps: Raw materials provided: chopped carbon fibers, reinforcing materials, carbon powder and binder, wherein the reinforcing materials include at least one of metal oxides and milled carbon fibers; The raw materials are mixed and then subjected to molding, carbonization and silicon infiltration processes in sequence to prepare carbon-ceramic composite materials.

2. The method for preparing the carbon-ceramic composite material as described in claim 1, wherein, The metal oxide includes at least one of aluminum oxide, yttrium oxide, and zirconium oxide.

3. The method for preparing the carbon-ceramic composite material according to any one of claims 1 to 2, wherein, The binder includes at least one of phenolic resin and asphalt.

4. The method for preparing the carbon-ceramic composite material according to any one of claims 1 to 3, wherein, The mass ratio of the binder, the carbon powder, and the reinforcing material is 20–35:10–35:0.5–15.

5. The method for preparing the carbon-ceramic composite material according to any one of claims 1 to 4, wherein, The chopped carbon fibers account for 30% to 60% of the total mass of the raw materials.

6. The method for preparing the carbon-ceramic composite material according to any one of claims 1 to 5, wherein, The length of the milled carbon fiber is 200μm to 800μm, the aspect ratio of the milled carbon fiber is 30 to 70:1, and the mass of the milled carbon fiber accounts for 0% to 10% of the total mass of the raw material.

7. The method for preparing the carbon-ceramic composite material according to any one of claims 1 to 6, wherein, The mixing of the raw materials includes the following steps: To prepare an intermediate mixture, the carbon powder, reinforcing materials and binder are mixed and then kneaded or mixed. The chopped carbon fibers are mixed with the intermediate mixture.

8. A method for preparing a carbon-ceramic composite material, comprising the following steps: The raw materials provided are: chopped carbon fibers, milled carbon fibers, carbon powder, and organic resin; wherein the length of the chopped carbon fibers is 8mm to 15mm, the length of the milled carbon fibers is 200μm to 500μm, the aspect ratio of the milled carbon fibers is 30 to 70:1, the mass of the milled carbon fibers accounts for 3% to 8% of the total mass of the raw materials, and the mass of the chopped carbon fibers accounts for 40% to 60% of the total mass of the raw materials. The raw materials are mixed and molded to prepare carbon fiber composite materials; The carbon fiber composite material was subjected to carbonization and silicon infiltration treatment in sequence to prepare a carbon-ceramic composite material.

9. The method for preparing the carbon-ceramic composite material as described in claim 8, wherein, The mass ratio of the chopped carbon fiber, the organic resin, the carbon powder, and the milled carbon fiber is 40-60:20-30:10-30:3-8.

10. The method for preparing the carbon-ceramic composite material according to any one of claims 7 to 9, wherein, The organic resin includes phenolic resin.

11. The method for preparing the carbon-ceramic composite material according to any one of claims 7 to 10, wherein, The raw materials also include additives, which include at least one of metal oxide powder and pore-forming agent.

12. The method for preparing the carbon-ceramic composite material as described in claim 11, wherein, The mass ratio of the additive to the chopped carbon fiber is 3-5:40-60.

13. A method for preparing a carbon ceramic product, comprising the following steps: To prepare an intermediate mixture, carbon powder, metal oxides, binders and additives are mixed and kneaded. Short-cut carbon fibers are mixed with the intermediate mixture to prepare a carbon fiber mixture; The carbon fiber mixture is subjected to molding, carbonization and silicon infiltration processes in sequence to prepare a carbon-ceramic composite material.

14. The method for preparing carbon ceramic products as described in claim 13, wherein, The mass ratio of the binder, the carbon powder, the additive, and the metal oxide is 25-35:10-30:3-5:0.5-2.

15. The method for preparing carbon ceramic articles according to any one of claims 13-14, wherein, The mass ratio of the chopped carbon fibers to the intermediate mixture is 0.5 to 1.5:

1.

16. The method for preparing carbon ceramic articles according to any one of claims 13 to 15, wherein, The binder includes at least one of solid phenolic resin, asphalt, and liquid resin.

17. The method for preparing carbon ceramic articles according to any one of claims 13 to 16, wherein, The additives include pore-forming agents.

18. The method for preparing carbon ceramic products as described in claim 17, wherein, The pore-forming agent includes at least one of ethylene glycol, PVB, and plant fiber powder.

19. The method for preparing the carbon-ceramic composite material as described in claim 7 or the method for preparing the carbon-ceramic article as described in any one of claims 13 to 18, wherein, The mixing temperature is 60℃~80℃, and the time is 10min~30min.

20. The method for preparing the carbon-ceramic composite material as described in claim 7 or the method for preparing the carbon-ceramic article as described in any one of claims 13 to 19, wherein, The mixing temperature is 120℃~150℃, and the time is 30min~120min.

21. The method for preparing the carbon-ceramic composite material as described in claim 7 or the method for preparing the carbon-ceramic article as described in any one of claims 13 to 20, wherein, In the step of mixing the chopped carbon fibers with the intermediate mixture, the mixing temperature is 20℃~35℃ and the stirring speed is 10r / min~30r / min.

22. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-21, or the method for preparing the carbon-ceramic article according to any one of claims 13-21, wherein, The surface of the chopped carbon fibers is coated with a sizing agent, which includes at least one of polyurethane and epoxy resin.

23. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-22, or the method for preparing the carbon-ceramic article according to any one of claims 13-22, wherein, The molding process is carried out at a temperature of 120℃ to 200℃.

24. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-23, or the method for preparing the carbon-ceramic article according to any one of claims 13-23, wherein, The molding process is carried out at a temperature of 150℃ to 200℃.

25. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-24, or the method for preparing the carbon-ceramic article according to any one of claims 13-24, wherein, The pressure of the molding process is 80 to 150 tons.

26. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-25, or the method for preparing the carbon-ceramic article according to any one of claims 13-25, wherein, The pressure of the molding process is 80 to 120 tons.

27. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-26, or the method for preparing the carbon-ceramic article according to any one of claims 13-26, wherein, The pressure of the molding process is 100 to 150 tons.

28. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-27, or the method for preparing the carbon-ceramic article according to any one of claims 13-27, wherein, The holding time for the molding process is 20 min to 40 min.

29. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-28, or the method for preparing the carbon-ceramic article according to any one of claims 13-28, wherein, The molding process is carried out using a flat vulcanizing machine.

30. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-29, or the method for preparing the carbon-ceramic article according to any one of claims 13-29, wherein, The carbonization treatment temperature is 900℃~1200℃, and the carbonization treatment time is 50h~70h.

31. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-30, or the method for preparing the carbon-ceramic article according to any one of claims 13-30, wherein, The carbonization temperature is 1000℃~1200℃.

32. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-31, or the method for preparing the carbon-ceramic article according to any one of claims 13-31, wherein, The silicon infiltration treatment is performed at a temperature of 1500℃ to 1700℃ for 3 hours to 6 hours.

33. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-32, or the method for preparing the carbon-ceramic article according to any one of claims 13-32, wherein, The silicon infiltration treatment takes 3 to 5 hours.

34. The method for preparing the carbon-ceramic composite material according to any one of claims 1-12, 19-33, or the method for preparing the carbon-ceramic article according to any one of claims 13-33, wherein, The silicon diffusion process includes: placing silicon sources on the upper and lower surfaces of the carbonized preform after carbonization treatment, and performing silicon diffusion in a silicon diffusion furnace.

35. The method for preparing the carbon-ceramic composite material as described in claim 34 or the method for preparing the carbon-ceramic product as described in claim 34, wherein, The silicon source includes elemental silicon.

36. A carbon-ceramic composite material, prepared by the method for preparing carbon-ceramic composite materials as described in any one of claims 1-12 and 19-35.

37. A carbon-ceramic brake disc comprising the carbon-ceramic composite material as described in claim 36.

38. A carbon ceramic product, prepared by the method for preparing carbon ceramic products as described in any one of claims 13 to 35.

39. The carbon ceramic product as described in claim 38, wherein, The carbon ceramic products include carbon ceramic brake discs.

40. A means of transportation, comprising a carbon ceramic brake disc as claimed in claim 37 or a carbon ceramic article as claimed in any one of claims 38 to 39.

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