CN106966751A - High-performance and low-cost C/C SiC ceramic matrix composite material brake discs and preparation method and application - Google Patents

Abstract

The invention relates to a high-performance and low-cost C/C‑SiC composite brake disc and its preparation method and application. The disc preform is densified to obtain a C/C composite material; then heat treatment is performed in an inert atmosphere to increase the degree of graphitization of the composite material; then mechanical processing is performed to obtain a C/C composite material green body; the C/C composite material is processed by fusion siliconization /C composite material green body to obtain a C/C-SiC composite material brake disc; then use the chemical vapor infiltration method or the precursor impregnation cracking method to process the C/C-SiC composite material brake disc; the obtained product Machining to the final design size, that is, the finished product of the composite material brake disc. The C/C-SiC composite brake disc and the preparation method thereof provided by the invention can reduce the preparation cost and improve the mechanical properties, thermal conductivity and friction and wear properties of the brake disc.

Description

High-performance and low-cost C/C-SiC composite brake disc and its preparation method and application

technical field

The invention relates to the technical field of composite material preparation, in particular to a high-performance and low-cost C/C-SiC composite brake disc and its preparation method and application.

Background technique

High-speed railway (hereinafter referred to as "high-speed railway") is the trend of the world's rail transit development. At present, the mileage of my country's high-speed railway has reached 10,000 kilometers, and the high-speed railway under construction is more than 10,000 kilometers. It is estimated that by 2021, the total mileage of China's high-speed railway will exceed 30,000 kilometers, ranking first in the world. With the rapid development of high-speed rail, its safety has also attracted much attention, among which braking technology is crucial to the safe operation of trains. At present, the braking methods used by high-speed rail mainly include electric braking and air braking, and there are also braking methods such as eddy current braking, magnetic rail braking and wind resistance braking. Among them, air braking is an emergency braking method. When a high-speed train encounters an emergency such as an earthquake, a power outage, or a train failure, it must be ensured that the high-speed train can stop within a specified distance to ensure the safety of the train. Therefore, air braking Braking, also known as "basic braking", is an indispensable and important part of the high-speed rail braking system.

The air brake mainly adopts two disc brake methods: shaft disc brake and wheel disc brake. Install the brake disc. At present, the materials of brake discs are mainly cast iron, cast steel and forged steel. The main advantages are that the manufacturing technology is mature, and the performance can meet the braking requirements of low-speed trains. However, with the continuous development of trains in the direction of "high speed" and "heavy load", the brake discs are required to have both high braking energy and light weight, but the existing brake disc materials are wear-resistant Poor performance, fast wear, poor heat dissipation, prone to thermal cracks, heavy weight, and high noise caused by friction, so it cannot well meet the development needs of trains with continuously increasing speed.

Contents of the invention

Aiming at the defects in the prior art, the purpose of the present invention is to provide a high-performance and low-cost C/C-SiC composite brake disc and its preparation method and application, so as to reduce the preparation cost and improve the mechanical properties and thermal conductivity of the brake disc. performance and friction and wear properties.

To achieve the above object, the technical solution provided by the invention is:

In a first aspect, the present invention provides a method for preparing a composite material brake disc, comprising the following steps:

S1: Carbonize the brake disc prefabricated body, and then use the chemical vapor deposition method to densify the carbonized brake disc prefabricated body to obtain a C/C composite material; wherein, the brake disc prefabricated body is made of polyacrylonitrile-based prefabricated Oxygen silk fibers are formed by three-dimensional needle punching; S2: heat-treating the C/C composite material in an inert atmosphere to obtain a C/C composite material green body; S3: treating the C/C composite material green body by fusion siliconizing method, Obtain the C/C-SiC composite brake disc; S4: process the C/C-SiC composite brake disc using chemical vapor deposition or precursor impregnation cracking; wherein, the precursor of chemical vapor deposition It is trichloromethylsilane, and the precursor solution of the precursor dipping and cracking method is a mixed solution of polycarbosilane and divinylbenzene; S5: the product obtained in step S4 is mechanically processed into the final design size to obtain a composite material. Finished disc.

It should be noted that in the three-dimensional acupuncture method, a single layer of 0° no-weft fabric, tire mesh, 90° no-weft fabric and tire mesh are stacked in sequence, and then the relay-type acupuncture method is used to introduce polyacrylamide in the direction perpendicular to the laying layer. Acrylonitrile-based pre-oxygenated silk fibers are used to make brake disc preforms. During the molten siliconizing process of step S3, the molten silicon reacts with the matrix C to form silicon carbide, and the volume shrinks after cooling to room temperature, resulting in the generation of microcracks; The thermal expansion coefficients of fiber, pyrolytic carbon, silicon carbide, and residual silicon are different in the material, which causes stress during the cooling process, and microcracks are generated under the action of stress. Step S4 is to fill the cracks of the C/C-SiC composite brake disc, reduce the residual amount of Si in the composite material, and improve the creep resistance of the composite material.

In a further embodiment of the present invention, in step S1, the chemical vapor deposition method is specifically: using one or more of propane, natural gas and propylene as the carbon source gas, nitrogen and/or hydrogen as the dilution gas, and the infiltration The temperature is 900-1200°C, the infiltration pressure is 1000-5000Pa, and the infiltration time is 50-200h; wherein, the volume ratio of carbon source gas and dilution gas is 1:(1-4).

In a further embodiment of the present invention, in step S2, the heat treatment temperature is 1800-2400° C., the treatment time is 1-5 hours, and the inert atmosphere is argon and/or nitrogen. Heat treatment is to improve the degree of graphitization of composite materials.

In a further embodiment of the present invention, in step S3, the molten siliconizing method is specifically: under vacuum conditions, the C/C composite body is placed in silicon powder with a particle size of 100-300 mesh, and then 1500-1700 mesh Keep warm at ℃ for 1.5~3.5h, then keep warm at 1750~2050℃ for 5~60min.

It should be noted that in order to meet the requirements of the reaction ratio, the content of SiC that needs to be generated during the molten siliconizing process can be calculated according to the difference between the expected density of the C/C-SiC composite brake disc and the density of the C/C composite body , so as to calculate the theoretically required amount of Si in the reaction of Si and C, take 2.2 to 5 times Si powder of the theoretically required amount of Si and place it in a graphite crucible. The purity of the Si powder is preferably greater than or equal to 99%, and the C/ The C brake disc green body is buried in Si powder, and then placed in a high temperature furnace for molten silicon infiltration, and the prepared C/C-SiC composite brake disc has a density of preferably 1.8-2.2 g/cm ³ . In order to save production costs, multiple graphite crucibles filled with Si powder and C/C composite body can also be stacked in a high-temperature furnace at the same time for fusion siliconization. During the fusion siliconizing process, the molten silicon infiltrates into the interior of the material from the pores of the C/C composite body under the combined action of capillary force and gravity, and reacts with the pyrolytic carbon in contact to form a SiC matrix phase, resulting in a C/C composite material. C-SiC composite brake disc, a small amount of unreacted molten Si remains in the C/C-SiC composite brake disc.

In a further embodiment of the present invention, in step S4, the chemical vapor deposition method is specifically: using trichloromethylsilane as a precursor (CH ₃ SiCl ₃ , MTS), hydrogen as a carrier gas, and argon as a diluent gas, The infiltration temperature is 900～1400℃, the infiltration pressure is 300～1200Pa, and the infiltration time is 15～25h; among them, the volume ratio of trichloromethylsilane, hydrogen and argon is 1:(7～10):( 3~5). It should be noted that MTS is a liquid precursor raw material, and hydrogen is used as a carrier gas. The gaseous MTS is brought into the reaction chamber by bubbling, and the inert gas argon is used as a diluent gas to adjust the pyrolysis reaction rate of MTS.

In a further embodiment of the present invention, in step S4, the precursor immersion cracking method specifically includes: immersing the C/C-SiC composite brake disc in a mixed solution of polycarbosilane and divinylbenzene for 30-60 minutes, then immersing The temperature is 60-100°C, the impregnation pressure is 1-2MPa, then curing and cross-linking at 110-200°C for 2-3.5 hours, and then cracking at 1100-1300°C for 0.5-2 hours; repeat the steps of the precursor impregnation cracking method until the cracks are completely filled seal; wherein, the mass fraction of polycarbosilane in the mixed solution of polycarbosilane and divinylbenzene is 40% to 60%.

In a further embodiment of the present invention, in step S1, the carbonization temperature is 1000-1400° C., the time is 45-75 hours, and the carbonization is carried out under vacuum conditions.

In a further embodiment of the present invention, after the heat treatment in step S2, before obtaining the C/C composite body, a step of mechanical processing is also included, specifically including: machining bolt holes on the surface of the C/C composite material after heat treatment and positioning holes; and/or process the dimensions around the C/C composite material, and leave a subsequent processing allowance of 1 to 2 mm in the thickness direction. It should be noted that: machining the heat-treated C/C composite material can be based on the aperture size requirements of the brake disc, machining bolt holes and positioning holes on the surface of the heat-treated C/C composite material; Negative tolerance requirements of the disk size, the size around the C/C composite material is processed, and a subsequent processing allowance of 1 to 2 mm is left in the thickness direction. The mechanical processing in step S5 can be a one-time thorough processing according to the size of the brake disc, or it can be based on this step of mechanical processing, and the prepared C/C-SiC composite brake disc is used on a grinding machine. The diamond grinding wheel performs surface processing on the friction surface, and removes the previously reserved 1-2mm subsequent processing allowance.

In a second aspect, the present invention provides a composite brake disc prepared according to any one of the above methods.

In a third aspect, the present invention provides the application of the above-mentioned composite material brake disc in the manufacture of trains, especially in the manufacture of high-speed rail.

The composite material brake disc provided by the invention and the preparation method thereof have the following positive effects: (1) the present invention proposes to use polyacrylonitrile-based pre-oxidized silk fiber as the reinforcing body of the carbon-ceramic double-base composite brake disc for high-speed rail for the first time, providing A manufacturing technique that can be mass-produced. Compared with carbon fiber, the price of pre-oxidized silk fiber is very low, and the preparation cost is greatly reduced when preparing the preform; the pre-oxidized silk fiber has a high elongation at breakage, good flexibility, and is suitable for acupuncture, while carbon fiber is a brittle material with a grooved surface. When needling, the fiber is subjected to great resistance, and it is easy to fall off or break off from the hook. Therefore, the surface of the pre-oxidized fiber preform is smoother than that of the carbon fiber preform, and the number and length of the Z-direction fibers are higher. The prepared carbon-ceramic double-matrix composite Material Z has high thermal conductivity, strong interlayer bonding, and excellent friction and wear properties, and is especially suitable for trains, especially high-speed rail brake disc materials. (2) The present invention adopts chemical vapor infiltration (CVI) or precursor impregnated cracking method (PIP) to carry out sealing crack treatment to the C/C-SiC composite material brake disk after molten siliconizing, the C/C after processing The C-Si composite brake disc has almost no cracks, which improves its mechanical properties; and the excess C produced by the PIP method can also react with the residual Si in the material after the molten siliconizing treatment to form SiC, which reduces the composite material. The residual amount of Si improves the creep resistance of the composite material. (3) The present invention chooses to carry out fusion siliconizing under two different high-temperature environments, and this reaction mode can make Si and the C reaction in the matrix more fully, reduce the number of closed cells and the number of closed cells in the C/C-SiC composite material The content of residual silicon improves the creep resistance, uniformity and mechanical properties of the composite material, and reduces the amount of friction and wear. (4) When the pyrolytic carbon content in the matrix is too high, the mechanical properties will be reduced, and if it is too low, the content of the ceramic matrix will be too high, the brake disc will be highly brittle, and the friction coefficient will be too high. The invention controls the content of matrix carbon and silicon carbide in the composite material by adjusting the content of pyrolytic carbon in the matrix, so that the mechanical properties and friction and wear properties of the composite material can be balanced.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

Fig. 1 is a schematic diagram of fused siliconization in an embodiment of the present invention.

Reference signs:

1-High temperature heating furnace; 2-Induction heating body; 3-Silicon powder; 4-Graphite crucible; 5-C/C composite material green body.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The experimental methods in the following examples are conventional methods unless otherwise specified.

The test materials used in the following examples, unless otherwise specified, were purchased from conventional reagent stores.

In the quantitative experiments in the following examples, three repeated experiments were set up, and the data were the mean value or mean ± standard deviation of the three repeated experiments.

The invention provides a method for preparing a composite material brake disc, which is characterized in that it comprises the following steps:

S1: Carbonize the brake disc prefabricated body, and then use the chemical vapor deposition method to densify the carbonized brake disc prefabricated body to obtain a C/C composite material; wherein, the brake disc prefabricated body is made of polyacrylonitrile-based prefabricated Oxygen silk fibers are formed by three-dimensional needle punching; the carbonization temperature is 1000-1400°C, the time is 45-75h, and the carbonization is carried out under vacuum conditions; the chemical vapor deposition method is specifically: one of propane, natural gas and propylene or several kinds of carbon source gas, nitrogen and/or hydrogen as dilution gas, infiltration temperature is 900-1200°C, infiltration pressure is 1000-5000Pa, and infiltration time is 50-200h; among them, carbon source gas and dilution gas The volume ratio is 1:(1~4).

S2: Heat-treat the C/C composite material in an inert atmosphere to increase the degree of graphitization of the composite material; the heat treatment temperature is 1800-2400°C, the treatment time is 1-5h, and the inert atmosphere is argon and/or nitrogen. Machining the heat-treated C/C composite material to obtain a C/C composite material green body, specifically including: machining bolt holes and positioning holes on the surface of the heat-treated C/C composite material; and/or machining the C/C composite material The dimensions around the material are processed, and a subsequent processing allowance of 1 to 2 mm is left in the thickness direction.

S3: process the C/C composite material green body by the molten siliconizing method to obtain a C/C-SiC composite material brake disc; the molten siliconizing method is specifically: under vacuum conditions, place the C/C composite material green body The particle size is 100-300 mesh silicon powder, then keep warm at 1500-1700°C for 1.5-3.5h, and then keep warm at 1750-2050°C for 5-60min.

S4: Use the chemical vapor deposition method or the precursor impregnation cracking method to seal the microcracks of the C/C-SiC composite brake disc; wherein, the precursor of the chemical vapor deposition method is trichloromethylsilane, the precursor The precursor solution of the bulk impregnation cracking method is a mixed solution of polycarbosilane and divinylbenzene; the chemical vapor deposition method is specifically: trichloromethylsilane (CH ₃ SiCl ₃ , MTS) as the precursor, hydrogen as the carrier Gas, argon is the dilution gas, the infiltration temperature is 900-1400°C, the infiltration pressure is 300-1200Pa, and the infiltration time is 15-25h; among them, the volume ratio of trichloromethylsilane, hydrogen and argon is 1 :(7～10):(3～5); Precursor impregnation cracking method is specifically: under vacuum conditions, the C/C-SiC composite brake disc is immersed in the mixed solution of polycarbosilane and divinylbenzene 30-60min, impregnation temperature is 60-100°C, impregnation pressure is 1-2MPa, then curing and crosslinking at 110-200°C for 2-3.5h, and then cleavage at 1100-1300°C for 0.5-2h; repeat the precursor immersion cracking method until the crack It is completely sealed; wherein, the mass fraction of polycarbosilane in the mixed solution of polycarbosilane and divinylbenzene is 40% to 60%.

S5: Machining the product obtained in step S4 into the final design size to obtain the finished composite brake disc.

The composite material brake disc provided by the present invention and the preparation method thereof will be further described below in conjunction with specific examples.

Embodiment one

The single-layer 0° no-weft cloth, tire net, 90° no-weft cloth, and tire net are superimposed in sequence, and then the polyacrylonitrile (PAN)-based pre-oxidized silk fiber is introduced in the direction perpendicular to the lay-up direction by the relay-type needling method. , to make a brake disc prefabricated body; under vacuum conditions, the brake disc prefabricated body was carbonized at a temperature of 1200 ° C for 60 hours; and then the carbonized brake disc prefabricated body was Densification, using propane as the carbon source gas, nitrogen as the diluent gas, the volume ratio of propane to nitrogen is 1:2, the infiltration temperature is 1150°C, the infiltration pressure is 3000Pa, the infiltration time is 120h, and the obtained density is 1.3g /cm ³ of C/C composites.

Under the protection of argon, the C/C composite material is subjected to high-temperature heat treatment at 2200 ° C for 2 hours; then it is machined, and according to the pore size requirements of the brake disc, the C/C composite material after the heat treatment Bolt holes and positioning holes are processed on the surface; according to the negative tolerance requirements of the brake disc size, the dimensions around the heat-treated C/C composite material are processed, and a subsequent machining allowance of 1 mm is left in the thickness direction to obtain C/C composite body.

Put the C/C composite body in a graphite crucible filled with silicon powder, put it into a high-temperature furnace for molten siliconization, as shown in Figure 1, specifically: under vacuum conditions, put the C/C composite body The body was buried in silicon powder with a particle size of 300 mesh, and then kept at 1650°C for 2.5h, and then kept at 1850°C for 10min to obtain a C/C-SiC composite brake disc with a density of 1.95g/cm ³ ; the purity of the silicon powder was 99.5%, the amount of silicon powder is 4 times the theoretical requirement of the reaction.

The obtained C/C-SiC composite brake disc was crack-filled by chemical vapor deposition method, using trichloromethylsilane (CH ₃ SiCl ₃ , MTS) as the liquid precursor raw material, hydrogen as the carrier gas, The gaseous MTS is brought into the reaction chamber by bubbling, and the inert gas argon is used as the diluent gas to adjust the pyrolysis reaction rate of MTS. The infiltration temperature is 1150°C, the infiltration pressure is 500Pa, and the infiltration time is 20h. The volume ratio of methylsilane, hydrogen and argon was 1:9:3 to obtain a C/C-SiC composite brake disc with a density of 1.97 g/ ^cm3 ; the resulting product was then machined into the final design Dimensions, using a diamond grinding wheel on the grinding machine to process the surface of the friction surface, remove the previously reserved 1mm subsequent processing allowance, and obtain the finished composite material brake disc.

Embodiment two

The single-layer 0° no-weft cloth, tire net, 90° no-weft cloth, and tire net are superimposed in sequence, and then the polyacrylonitrile (PAN)-based pre-oxidized silk fiber is introduced in the direction perpendicular to the lay-up direction by the relay-type needling method. , to make a brake disc prefabricated body; under vacuum conditions, the brake disc prefabricated body was carbonized at a temperature of 1200 ° C for 60 hours; and then the carbonized brake disc prefabricated body was Densification, using propane as the carbon source gas, nitrogen as the diluent gas, the volume ratio of propane to nitrogen is 1:2, the infiltration temperature is 1150°C, the infiltration pressure is 3000Pa, the infiltration time is 120h, and the obtained density is 1.3g /cm ³ of C/C composites.

Under the protection of argon, the C/C composite material is subjected to high-temperature heat treatment at 2200 ° C for 2 hours; then it is machined, and according to the pore size requirements of the brake disc, the C/C composite material after the heat treatment Bolt holes and positioning holes are processed on the surface; according to the negative tolerance requirements of the brake disc size, the dimensions around the heat-treated C/C composite material are processed, and a subsequent machining allowance of 1 mm is left in the thickness direction to obtain C/C composite body.

Put the C/C composite body in a graphite crucible filled with silicon powder, put it into a high-temperature furnace for molten siliconization, as shown in Figure 1, specifically: under vacuum conditions, put the C/C composite body The body was buried in silicon powder with a particle size of 300 mesh, and then kept at 1650°C for 2.5h, and then kept at 1850°C for 10min to obtain a C/C-SiC composite brake disc with a density of 1.95g/cm ³ ; the purity of the silicon powder was 99.5%, the amount of silicon powder is 4 times the theoretical requirement of the reaction.

The cracks of the obtained C/C-SiC composite brake disc were filled by the precursor impregnation cracking method, and the mixed solution of polycarbosilane (PCS) and divinylbenzene was used as the precursor solution, in which polycarbosilane and The mass fraction of polycarbosilane in the mixed solution of divinylbenzene is 45%, the C/C-SiC composite brake disc is immersed in the mixed solution of polycarbosilane and divinylbenzene for 30min, and the immersion temperature is 70°C , the immersion pressure is 1.5MPa, then curing and crosslinking at 150°C for 3h, and then cracking at 1200°C for 1h; repeat the above precursor dipping and cracking method 5 times to obtain C/C-SiC with a density of 1.96g/cm ³ Composite brake discs. Then, the obtained product is machined into the final design size, and the friction surface is processed on the grinding machine with a diamond grinding wheel, and the 1 mm subsequent processing allowance reserved before is removed to obtain the finished composite material brake disc.

The performance of the composite brake discs prepared in Examples 1 and 2 of the present invention was tested, and the specific test methods and test results are as follows.

Test method: 1:1 dynamic bench test was carried out on the composite brake discs prepared in Example 1 and Example 2, respectively, to confirm their friction and wear properties. The test conditions are repeated emergency braking 40 times at a speed of 400km/h (20 times under dry and wet conditions), and the friction and wear performance of the friction surface of the brake disc is tested.

Test results: the specific results are shown in Table 1 below.

Table 1 Performance test results of composite brake discs

The composite brake discs prepared in Example 1 and Example 2 all showed excellent performance in the wet braking test, and the change rate of the dry and wet friction coefficient of the composite brake disc prepared in Example 1 was only is 2.6%, and the change rate of the dry and wet friction coefficient of the composite brake disc prepared in Example 2 is only 2.7%, so there is almost no problem of attenuation of wet friction performance.

It should be noted that, in addition to the cases listed in the first and second examples above, it is also feasible to select other parameters of the preparation method.

The C/C-SiC composite material brake disk and the preparation method thereof provided by the invention can reduce the preparation cost and improve the mechanical performance, thermal conductivity and friction and wear performance of the brake disk.

The composite material brake disc provided by the invention and the preparation method thereof have the following positive effects: (1) the present invention proposes to use polyacrylonitrile-based pre-oxidized silk fiber as the reinforcing body of the carbon-ceramic double-base composite brake disc for high-speed rail for the first time, providing A manufacturing technique that can be mass-produced. Compared with carbon fiber, the price of pre-oxidized silk fiber is very low, and the preparation cost is greatly reduced when preparing the preform; the pre-oxidized silk fiber has a high elongation at breakage, good flexibility, and is suitable for acupuncture, while carbon fiber is a brittle material with a grooved surface. The resistance to the fiber is large during needle punching, and it is easy to fall off or break off from the hook. Therefore, the surface of the pre-oxidized silk fiber preform is smoother than that of the carbon fiber preform, and the number and length of the Z-direction fibers are higher. The prepared carbon-ceramic double-base The composite material Z has high thermal conductivity, strong interlayer bonding, and excellent friction and wear properties, and is especially suitable for trains, especially high-speed rail brake disc materials. (2) The present invention adopts chemical vapor infiltration (CVI) or precursor impregnated cracking method (PIP) to carry out sealing crack treatment to the C/C-SiC composite material brake disk after molten siliconizing, the C/C after processing The C-Si composite brake disc has almost no cracks, which improves its mechanical properties; and the excess C produced by the PIP method can also react with the residual Si in the material after the molten siliconizing treatment to form SiC, which reduces the composite material. The residual amount of Si improves the creep resistance of the composite material. (3) The present invention chooses to carry out fusion siliconizing under two different high-temperature environments, and this reaction mode can make Si and the C reaction in the matrix more fully, reduce the number of closed cells and the number of closed cells in the C/C-SiC composite material The content of residual silicon improves the creep resistance, uniformity and mechanical properties of the composite material, and reduces the amount of friction and wear. (4) When the pyrolytic carbon content in the matrix is too high, the mechanical properties will be reduced, and if it is too low, the content of the ceramic matrix will be too high, the brake disc will be highly brittle, and the friction coefficient will be too high. The invention controls the content of matrix carbon and silicon carbide in the composite material by adjusting the content of pyrolytic carbon in the matrix, so that the mechanical properties and friction and wear properties of the composite material can be balanced.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples" or "some examples" mean specific features described in connection with the embodiment or example, A structure, material or characteristic is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are changed, modified, replaced and modified without making the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention, and all of them should be covered by the scope of the claims and description of the present invention.

Claims (10)

1. a kind of preparation method of composite brake disk, it is characterised in that comprise the following steps：

S1:Brake disc precast body is carbonized, then the brake disc precast body after the carbonization is caused using chemical vapor infiltration area method Densification, obtains C/C composites；Wherein, the brake disc precast body is to use polyacrylonitrile-radical oxidization fiber fiber with three dimensional needle Thorn is formed；

S2:The C/C composites are heat-treated in an inert atmosphere, C/C composite bodies are obtained；

S3:The C/C composite bodies are handled using siliconising method is melted, C/C-SiC composite brake disks are obtained；

S4:By the C/C-SiC composite brakes disk using chemical vapor infiltration area method or precursor infiltration and pyrolysis method at Reason；Wherein, the precursor of the chemical vapor infiltration area method is trichloromethyl silane, the precursor of the precursor infiltration and pyrolysis method Solution is the mixed solution of Polycarbosilane and divinylbenzene；

S5:The obtained products of the step S4 are machined into final design size, composite brake disk finished product is produced.

2. the preparation method of composite brake disk according to claim 1, it is characterised in that：In the step S1, institute Stating chemical vapor infiltration area method is specially：With in propane, natural gas and propylene one or more for carbon-source gas, nitrogen and/or Hydrogen is diluent gas, oozes accumulated temperature degree for 900~1200 DEG C, oozes overstocked power for 1000~5000Pa, ooze the long-pending time for 50~ 200h；Wherein, the volume ratio of the carbon-source gas and the diluent gas is 1:(1~4).

3. the preparation method of composite brake disk according to claim 1, it is characterised in that：In the step S2, institute The treatment temperature for stating heat treatment is 1800~2400 DEG C, and processing time is 1~5h, and the inert atmosphere is argon gas and/or nitrogen.

4. the preparation method of composite brake disk according to claim 1, it is characterised in that：In the step S3, institute Stating melting siliconising method is specially：Under vacuum, the C/C composite bodies are placed in the silicon that particle diameter is 100~300 mesh In powder, then 1500~1700 DEG C of 1.5~3.5h of insulation, then 1750~2050 DEG C of 5~60min of insulation.

5. the preparation method of composite brake disk according to claim 1, it is characterised in that in the step S4, institute Stating chemical vapor infiltration area method is specially：Using trichloromethyl silane as precursor, hydrogen is carrier gas, and argon gas is carrier gas, oozes accumulated temperature Spend for 900~1400 DEG C, ooze overstocked power for 300~1200Pa, ooze the long-pending time for 15~25h；Wherein, the trichloromethyl silicon The volume ratio of alkane, the hydrogen and the argon gas is 1:(7~10):(3~5).

6. the preparation method of composite brake disk according to claim 1, it is characterised in that：In the step S4, institute Stating precursor infiltration and pyrolysis method is specially：The C/C-SiC composite brakes disk is impregnated in Polycarbosilane and divinyl 30~60min of mixed solution of benzene, the dipping temperature is 60~100 DEG C, and the impregnation pressure is 1~2MPa, then 110~ 200 DEG C of solidification 2~3.5h of crosslinking, then 1100~1300 DEG C of 0.5~2h of cracking；The step of repeating the precursor infiltration and pyrolysis method Until crackle is filled out envelope completely；Wherein, the quality of Polycarbosilane is divided in the mixed solution of the Polycarbosilane and divinylbenzene Number is 40%~60%.

7. the preparation method of composite brake disk according to claim 1, it is characterised in that：In the step S1, institute The temperature for stating carbonization is 1000~1400 DEG C, and the time is 45~75h, and the carbonization is carried out under vacuum.

8. the preparation method of composite brake disk according to claim 1, it is characterised in that：In the institute of the step S2 After stating heat treatment, before obtaining the C/C composite bodies, in addition to the step of machining, specifically include：Will be described C/C composite material surfaces after heat treatment process bolt hole and positioning hole；And/or to the chi of the C/C composites surrounding It is very little to be processed, and reserve 1~2mm following process surplus in thickness direction.

9. the composite brake disk that the method described in any one of claim 1~8 is prepared.

10. application of the composite brake disk in manufacture train especially manufactures high ferro described in claim 9.