CN111484349A - Preparation method of carbon-based brake material - Google Patents
Preparation method of carbon-based brake material Download PDFInfo
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- CN111484349A CN111484349A CN202010321726.0A CN202010321726A CN111484349A CN 111484349 A CN111484349 A CN 111484349A CN 202010321726 A CN202010321726 A CN 202010321726A CN 111484349 A CN111484349 A CN 111484349A
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/71—Ceramic products containing macroscopic reinforcing agents
- C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
- C04B35/80—Fibres, filaments, whiskers, platelets, or the like
- C04B35/83—Carbon fibres in a carbon matrix
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/46—Gases other than oxygen used as reactant, e.g. nitrogen used to make a nitride phase
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/48—Organic compounds becoming part of a ceramic after heat treatment, e.g. carbonising phenol resins
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/77—Density
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Composite Materials (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Ceramic Products (AREA)
- Braking Arrangements (AREA)
Abstract
The invention belongs to the technical field of braking devices, and discloses a preparation method of a carbon-based braking material, which comprises the following steps: placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a CVI (chemical vapor deposition) process; then placing the mixture in a liquid phase impregnation furnace, and densifying by adopting a liquid phase impregnation process; placing the impregnated carbon/carbon composite material blank in a curing furnace for curing; machining the cured carbon/carbon composite material blank; the carbon/ceramic brake material product is obtained by performing RMI densification treatment on the carbon/carbon workpiece subjected to mechanical processing, and the preparation method is a preparation method of the carbon-based composite material with short period, low cost and excellent frictional wear performance.
Description
Technical Field
The invention belongs to the technical field of braking devices, and particularly relates to a preparation method of a carbon-based braking material.
Background
The carbon-based composite brake material comprises a carbon/carbon composite material and a carbon/ceramic composite material, and has the advantages of high specific strength, high specific modulus, high heat capacity, excellent high-temperature mechanical property, unique frictional wear characteristic, ablation resistance, multi-directional designability and the like, so that the carbon-based composite brake material becomes a popular material in the field of national defense and civil high-end brakes. The preparation method of the carbon/carbon composite brake material mainly comprises a chemical vapor deposition (CVI) method and a liquid phase impregnation method, and the preparation method of the carbon/ceramic composite brake material mainly comprises a Reaction Melt Infiltration (RMI) method. Carbon/carbon composites and carbon/ceramic composites have been widely used in aircraft braking applications and have evolved gradually to non-aerospace applications. However, the carbon/carbon composite material brake disc prepared by the chemical vapor deposition (CVI) method at present has the defects of high cost and long period, the carbon/carbon composite material brake disc prepared by the liquid phase impregnation method has the defect of large abrasion loss, and the carbon ceramic composite material brake disc prepared by the Reaction Melt Infiltration (RMI) method has the defect of brake jitter.
Disclosure of Invention
In order to solve the technical problems, the embodiment of the invention provides a preparation method of a carbon-based brake material, which is a preparation method of a carbon-based composite material with short period, low cost and excellent friction and wear properties.
In order to achieve the purpose, the invention is realized by adopting the following technical scheme.
A method of preparing a carbon-based brake material, the method comprising:
s1, obtaining a three-dimensional needled felt prefabricated body;
s2, placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a CVI (chemical vapor deposition) process to obtain a carbon/carbon composite material blank;
s3, placing the carbon-carbon composite material blank in a liquid-phase impregnation furnace, and densifying by adopting a liquid-phase impregnation process to obtain an impregnated carbon/carbon composite material blank;
s4, placing the impregnated carbon/carbon composite material blank in a curing furnace for curing to obtain a cured carbon/carbon composite material blank;
s5, repeating S3-S4 in sequence until the density of the cured carbon/carbon composite material green body reaches a preset density;
s6, machining the solidified carbon/carbon composite material blank to obtain a machined carbon/carbon workpiece;
and S7, performing RMI densification treatment on the machined carbon/carbon workpiece to obtain the carbon/ceramic brake material product.
The technical scheme of the invention has the characteristics and further improvements that:
(1) in S2, the deposition is performed by CVI process, and the carbon source gas used for deposition is natural gas or propylene gas.
(2) In the deposition process of S2 by adopting a CVI process, the deposition temperature is 800-1100 ℃, and the deposition time is 50-100 h.
(3) S3, when the densification is carried out by adopting a liquid-phase impregnation process, the impregnation liquid level resin is adopted, the impregnation temperature is 50-75 ℃, the impregnation pressure is 5-25 atm, and the impregnation time is 8-20 h, thereby obtaining the impregnated carbon/carbon composite material blank.
(4) S4, when the impregnated carbon/carbon composite material blank is placed in a curing furnace for curing, the curing pressure is 3 atm-8 atm, and the curing temperature is 180 ℃.
(5) Heating is carried out before the curing temperature is reached, the heating rate of 0.3 ℃/min-0.8 ℃/min is adopted in the heating process, and the temperature is respectively maintained for 1h at 100 ℃, 120 ℃, 150 ℃ and 180 ℃.
(6) The predetermined density of S5 is 1.35-1.60 g/cm 3.
(7) S7, during the RMI densification treatment process of the machined carbon/carbon workpiece, the vacuum degree of the RMI process is 5 KPa-20 KPa, the temperature is 1600-1800 ℃, and the heat preservation time is 60-120 min.
(8) The density of the obtained carbon/ceramic brake material product is 1.8g/cm 3-2.2 g/cm 3.
The embodiment of the invention provides a preparation method of a carbon-based composite material with short period, low cost and excellent frictional wear performance.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in detail below. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.
The process steps of the invention are as follows:
step 1, CVI pretreatment.
And placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a conventional (CVI process) process to obtain a carbon/carbon composite material blank, wherein a carbon source gas used for deposition is natural gas or propylene gas, the deposition temperature is 800-1100 ℃, and the deposition time is 50-100 h, so that the density of the carbon/carbon composite material blank reaches 1.1-1.35 g/cm 3.
And 2, impregnating the carbon/carbon blank.
And placing the carbon/carbon blank obtained by deposition into a liquid phase impregnation furnace, and densifying by adopting a conventional liquid phase impregnation process. The impregnation liquid is resin, the impregnation temperature is 50-75 ℃, the pressure is 5-25 atm (atmospheric pressure), and the time is 8-20 h.
And 3, solidifying the carbon/carbon blank.
The impregnated carbon/carbon blank is placed in a curing oven and cured using conventional techniques. The curing pressure is 3 atm-8 atm, the temperature is 180 ℃, a step-rising heat preservation mode is adopted in the temperature rising process, namely, the temperature rising speed is 0.3 ℃/min-0.8 ℃/min, and the temperature is preserved for 1h at 100 ℃, 120 ℃, 150 ℃ and 180 ℃ respectively.
And 4, liquid phase impregnation densification.
And (3) repeating the step (2) to the step (3) to ensure that the density of the carbon/carbon blank body reaches 1.4 to 1.60g/cm 3.
And 5, machining.
And processing the carbon/carbon blank subjected to liquid phase impregnation according to the requirements of the drawing.
And 6, RMI densification treatment.
The machined carbon/carbon workpiece was placed in a crucible containing silicon powder for RMI densification. The vacuum degree of the RMI process is 5KPa to 20KPa, the temperature is 1600 ℃ to 1800 ℃, the heat preservation time is 60min to 120min, and the density reaches 1.8g/cm3 to 2.2g/cm 3.
Example one
The embodiment is a method for preparing a carbon/ceramic brake material product, which comprises the following specific steps:
step 1, CVI pretreatment.
And (3) placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a conventional process, wherein a carbon source gas is natural gas, the deposition temperature is 1100 ℃, the deposition time is 50 hours, and the density of the blank body reaches 1.1-1.35 to obtain the carbon/carbon blank.
And 2, impregnating the carbon/carbon blank.
And (3) placing the carbon/carbon blank obtained by deposition into a liquid phase impregnation furnace, and performing liquid phase impregnation by adopting a conventional process. The impregnation liquid is resin, the impregnation temperature is 50 ℃, the pressure is 25atm, and the time is 20 h.
And 3, solidifying the carbon/carbon blank.
The impregnated carbon/carbon blank is placed in a curing oven and cured using conventional techniques. The curing pressure is 3atm, the temperature is 180 ℃, a step-rising heat preservation mode is adopted in the temperature rising process, namely, the temperature rising rate is 0.3 ℃/min, and the temperature is respectively preserved for 1h at 100 ℃, 120 ℃, 150 ℃ and 180 ℃.
And 4, liquid phase impregnation densification.
And (5) repeating the step (2) to the step (3) to enable the density of the carbon/carbon blank to reach 1.4-1.60.
And 5, machining.
And processing the carbon/carbon blank subjected to liquid phase impregnation according to the requirements of the drawing.
And 6, RMI densification treatment.
The machined carbon/carbon workpiece was placed in a crucible containing silicon powder for RMI densification. The vacuum degree of the RMI process is 5-20 KPa, the temperature is 1600 ℃, the heat preservation time is 120min, and the density reaches 1.8g/cm 3-2.2 g/cm 3.
Example two
The embodiment is a method for preparing a carbon/ceramic brake material product, which comprises the following specific steps:
step 1, CVI pretreatment.
And (3) placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a conventional process, wherein a carbon source gas is an propylene gas, the deposition temperature is 800 ℃, the deposition time is 100 hours, and the density of the blank body reaches 1.1-1.35 to obtain the carbon/carbon blank.
And 2, impregnating the carbon/carbon blank.
And (3) placing the carbon/carbon blank obtained by deposition into a liquid phase impregnation furnace, and performing liquid phase impregnation by adopting a conventional process. The impregnation liquid is resin, the impregnation temperature is 75 ℃, the pressure is 5atm, and the time is 15 h.
And 3, solidifying the carbon/carbon blank.
The impregnated carbon/carbon blank is placed in a curing oven and cured using conventional techniques. The curing pressure is 8atm, the temperature is 180 ℃, a step-rising heat preservation mode is adopted in the temperature rising process, namely, the temperature rising rate is 0.5 ℃/min, and the temperature is respectively preserved for 1h at 100 ℃, 120 ℃, 150 ℃ and 180 ℃.
And 4, liquid phase impregnation densification.
And (5) repeating the step (2) to the step (3) to enable the density of the carbon/carbon blank to reach 1.4-1.60.
And 5, machining.
And processing the carbon/carbon blank subjected to liquid phase impregnation according to the requirements of the drawing.
And 6, RMI densification treatment.
The machined carbon/carbon workpiece was placed in a crucible containing silicon powder for RMI densification. The vacuum degree of the RMI process is 5KPa to 20KPa, the temperature is 1800 ℃, the heat preservation time is 60min, and the density reaches 1.8g/cm3 to 2.2g/cm 3.
EXAMPLE III
The embodiment is a method for preparing a carbon/ceramic brake material product, which comprises the following specific steps:
step 1, CVI pretreatment.
And (3) placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a conventional process, wherein a carbon source gas is natural gas, the deposition temperature is 1000 ℃, the deposition time is 80 hours, and the density of the blank body reaches 1.1-1.35 to obtain the carbon/carbon blank.
And 2, impregnating the carbon/carbon blank.
And (3) placing the carbon/carbon blank obtained by deposition into a liquid phase impregnation furnace, and performing liquid phase impregnation by adopting a conventional process. The impregnation liquid is resin, the impregnation temperature is 65 ℃, the pressure is 15atm, and the time is 8 h.
And 3, solidifying the carbon/carbon blank.
The impregnated carbon/carbon blank is placed in a curing oven and cured using conventional techniques. The curing pressure is 5atm, the temperature is 180 ℃, a step-rising heat preservation mode is adopted in the temperature rising process, namely, the temperature rising rate is 0.8 ℃/min, and the temperature is respectively preserved for 1h at 100 ℃, 120 ℃, 150 ℃ and 180 ℃.
And 4, liquid phase impregnation densification.
And (5) repeating the step (2) to the step (3) to enable the density of the carbon/carbon blank to reach 1.4-1.60.
And 5, machining.
And processing the carbon/carbon blank subjected to liquid phase impregnation according to the requirements of the drawing.
And 6, RMI densification treatment.
The machined carbon/carbon workpiece was placed in a crucible containing silicon powder for RMI densification. The vacuum degree of the RMI process is 5-20 KPa, the temperature is 1750 ℃, and the heat preservation time is 90min, so that the density reaches 1.8g/cm 3-2.2 g/cm 3.
Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (9)
1. A preparation method of a carbon-based brake material is characterized by comprising the following steps:
s1, obtaining a three-dimensional needled felt prefabricated body;
s2, placing the three-dimensional needled felt preform in a chemical vapor deposition furnace, and depositing by adopting a CVI (chemical vapor deposition) process to obtain a carbon/carbon composite material blank;
s3, placing the carbon-carbon composite material blank in a liquid-phase impregnation furnace, and densifying by adopting a liquid-phase impregnation process to obtain an impregnated carbon/carbon composite material blank;
s4, placing the impregnated carbon/carbon composite material blank in a curing furnace for curing to obtain a cured carbon/carbon composite material blank;
s5, repeating S3-S4 in sequence until the density of the cured carbon/carbon composite material green body reaches a preset density;
s6, machining the solidified carbon/carbon composite material blank to obtain a machined carbon/carbon workpiece;
and S7, performing RMI densification treatment on the machined carbon/carbon workpiece to obtain the carbon/ceramic brake material product.
2. The method as claimed in claim 1, wherein the deposition in S2 is performed by CVI process, and the carbon source gas used for the deposition is natural gas or propylene gas.
3. The method for preparing a carbon-based brake material as claimed in claim 1, wherein the deposition temperature is 800 ℃ to 1100 ℃ and the deposition time is 50h to 100h in the deposition process of S2 by using a CVI process.
4. The method of claim 1, wherein the S3 is a liquid resin impregnation method, the impregnation temperature is 50 ℃ to 75 ℃, the impregnation pressure is 5atm to 25atm, and the impregnation time is 8h to 20h, so as to obtain an impregnated carbon/carbon composite material blank.
5. The method of claim 1, wherein the impregnated carbon/carbon composite material is cured in a curing oven at a curing pressure of 3atm to 8atm and a curing temperature of 180 ℃ in the step S4.
6. The method for preparing a carbon-based brake material according to claim 5, wherein the temperature is raised before the curing temperature is reached, wherein the temperature is raised at a rate of 0.3 ℃/min to 0.8 ℃/min and maintained at 100 ℃, 120 ℃, 150 ℃ and 180 ℃ for 1 hour.
7. The method for preparing a carbon-based brake material as claimed in claim 1, wherein the predetermined density in S5 is 1.35-1.60 g/cm 3.
8. The method for preparing the carbon-based brake material as claimed in claim 1, wherein in the process of performing RMI densification treatment on the machined carbon/carbon workpiece by S7, the vacuum degree of the RMI process is 5KPa to 20KPa, the temperature is 1600 ℃ to 1800 ℃, and the holding time is 60min to 120 min.
9. The preparation method of the carbon-based brake material as claimed in claim 8, wherein the density of the obtained carbon/ceramic brake material product is 1.8g/cm 3-2.2 g/cm 3.
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| CN202010321726.0A CN111484349A (en) | 2020-04-22 | 2020-04-22 | Preparation method of carbon-based brake material |
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| CN202010321726.0A CN111484349A (en) | 2020-04-22 | 2020-04-22 | Preparation method of carbon-based brake material |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112110743A (en) * | 2020-08-31 | 2020-12-22 | 常州翊翔炭材科技有限公司 | CVI, PIP and RMI combined process for preparing carbon/carbon ceramic composite material brake disc |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101818048A (en) * | 2010-01-21 | 2010-09-01 | 中南大学 | Method for preparing copper silicon alloy modified carbon/ceramic friction material |
| CN103922777A (en) * | 2014-04-09 | 2014-07-16 | 上海大学 | Method for preparing carbon/carbon-silicon carbide composite material for bearings |
| CN107058915A (en) * | 2017-04-20 | 2017-08-18 | 湖南锴博新材料科技有限公司 | A kind of infiltration powder containing chromium and its application in copper chrome-silicon modified carbon/ceramic friction material |
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2020
- 2020-04-22 CN CN202010321726.0A patent/CN111484349A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101818048A (en) * | 2010-01-21 | 2010-09-01 | 中南大学 | Method for preparing copper silicon alloy modified carbon/ceramic friction material |
| CN103922777A (en) * | 2014-04-09 | 2014-07-16 | 上海大学 | Method for preparing carbon/carbon-silicon carbide composite material for bearings |
| CN107058915A (en) * | 2017-04-20 | 2017-08-18 | 湖南锴博新材料科技有限公司 | A kind of infiltration powder containing chromium and its application in copper chrome-silicon modified carbon/ceramic friction material |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112110743A (en) * | 2020-08-31 | 2020-12-22 | 常州翊翔炭材科技有限公司 | CVI, PIP and RMI combined process for preparing carbon/carbon ceramic composite material brake disc |
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