CN105198473A - Preparation method of carbon/carbon brake disc - Google Patents
Preparation method of carbon/carbon brake disc Download PDFInfo
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- CN105198473A CN105198473A CN201510555712.4A CN201510555712A CN105198473A CN 105198473 A CN105198473 A CN 105198473A CN 201510555712 A CN201510555712 A CN 201510555712A CN 105198473 A CN105198473 A CN 105198473A
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Abstract
The invention provides a preparation method of a carbon/carbon brake disc. The preparation method comprises three stages including CVI (chemical vapor infiltration) early-stage compaction, CVI middle-stage compaction and CVI late-stage compaction. In the compaction process, the compaction speed needs to be reasonably controlled; the influence of too high compaction speed on the final density of the subsequent compaction and the carbon/carbon brake disc is prevented; or the influence of too low compaction speed on the manufacturing period of the carbon/carbon brake disc is prevented. By regulating the technical parameters, the compaction speed is controlled at the compactness increase value being 0.2 to 0.4g/cm<3> per hundred hours in the three compaction stages, so that the final density of the carbon/carbon brake disc can reach higher than 1.80/cm<3>. Pyrolytic carbon formed by the method provided by the invention is of an amorphous rough body structure. The amorphous rough body pyrolytic carbon can absorb water vapor in the air and can maintain the water vapor in the air; the friction membrane can be easily formed; the abrasion of the carbon/carbon brake disc can be greatly reduced through the formation of the friction membrane.
Description
Technical field
The present invention relates to charcoal/carbon/carbon brake disc and manufacture field, specifically a kind of manufacture method for aircraft, racing car, bullet train brake material.
Background technology
Charcoal/carbon/carbon brake disc is a kind of is reinforcement with Carbon fibe, with the matrix material that pyrolytic carbon, resin carbon or asphalt carbon are matrix, there is due to it features such as high specific heat capacity, higher mechanical property, good heat conductivility and friction and wear behavior and be widely used in aircraft finance lease.
The major processes that charcoal/carbon/carbon brake disc manufactures in enormous quantities is chemical vapor infiltration (CVI).CVI technique is under certain temperature and pressure, and by the cracking under vacuum of carbon source gas, the charcoal of generation progressively deposits to shaping porous preform and strengthens in the hole of skeleton, until homogenous densification.Charcoal/carbon/carbon brake disc has excellent braking quality under different brake condition, but charcoal/carbon/carbon brake disc still exists the problem of life-span deficiency in use procedure.
Xi'an Aviation Brake Technology Co., Ltd. is a kind of segmented deposition method disclosing carbon/carbon/carbon composition braking material in the innovation and creation of 201010051490.X at application number, the method adopts propylene gas CVI densification early stage, later stage adopts Sweet natural gas CVI densification, the method mainly improves the work-ing life of carbon/carbon/carbon composition braking material under high speed brake condition, does not solve the problem of charcoal/carbon/carbon brake disc life-span deficiency completely.
Summary of the invention
For overcoming the problem of the charcoal/carbon/carbon brake disc life-span deficiency existed in prior art, the present invention proposes a kind of preparation method of charcoal/carbon/carbon brake disc.
Detailed process of the present invention comprises the following steps:
Step 1, heat-treats Carbon fibe precast body: Carbon fibe precast body is put into heat treatment furnace, is evacuated to≤1000Pa, be warming up to 2400 ~ 2600 DEG C to heat treatment furnace, is incubated and heat-treats for 5 ~ 10 hours.When temperature is at 1350 ~ 1450 DEG C, send argon shield; Obtain the precast body after thermal treatment.
Step 2, CVI densification in early stage: the precast body after thermal treatment is put into CVI stove and carries out densification in early stage.The processing parameter of densification in early stage is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 2000 ~ 4000L/h.Until the density of precast body density is 1.30 ~ 1.40g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in early stage.
Step 3, surface working: according to a conventional method surface working is carried out to the charcoal/carbon/carbon brake disc base substrate through densification in early stage obtained.
Step 4, CVI densification in mid-term: the charcoal/carbon/carbon brake disc base substrate through densification in early stage is put into CVI stove and carries out densification in mid-term.The processing parameter of densification in mid-term is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 4000 ~ 6000 ls/h.Until the density of precast body density is 1.50 ~ 1.60g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in mid-term.
Step 5, surface working: according to a conventional method surface working is carried out to the charcoal/carbon/carbon brake disc base substrate through densification in early stage obtained.
Step 6, CVI later stage densification: the charcoal/carbon/carbon brake disc base substrate through densification in mid-term is put into CVI stove and carries out later stage densification.The processing parameter of later stage densification is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 3000 ~ 5000 ls/h.Until the density of precast body density is 1.80/cm
3above; Obtain the charcoal/carbon/carbon brake disc base substrate through later stage densification.
Step 7, finally processes; Charcoal/carbon/carbon brake disc base substrate is required finally to process according to product drawing, obtains charcoal/carbon/carbon brake disc.
Charcoal/carbon/carbon brake disc mainly comprises the pyrolytic carbon two portions formed in the charcoal/carbon/carbon brake disc base substrate and densification process formed by Carbon fibe acupuncture.The intensity of charcoal/carbon/carbon brake disc and charcoal/carbon/carbon brake disc base substrate closely related, depend primarily on the density of pyrolytic carbon and charcoal/carbon/carbon brake disc the work-ing life of charcoal/carbon/carbon brake disc.Pyrolytic carbon comprises isotropic body, smooth body and asperities.Indefiniteness charcoal and crystal charcoal is divided into again in isotropic body, smooth body and asperities.The structure of pyrolytic carbon is determined by the processing parameter in densification process.
Pyrolytic carbon in the charcoal/carbon/carbon brake disc adopting the present invention to be formed is indefiniteness asperity configurations.Indefiniteness asperities pyrolytic carbon can absorb the aqueous vapor in air and keep, and is easy to form friction film, and the formation of friction film can reduce the wearing and tearing of charcoal/carbon/carbon brake disc greatly.
The present invention includes CVI densification in early stage, CVI densification in mid-term and CVI later stage densification three phases.In densification process, need conservative control densification rate, when densification rate is too fast, more closed pore can be formed in charcoal/carbon/carbon brake disc inside, affect the final densities of subsequent densification and charcoal/carbon/carbon brake disc; Densification rate is excessively slow, can affect the manufacturing cycle of charcoal/carbon/carbon brake disc.Densification rate, by adjusting process parameter, controls at every hundred hours density 0.2-0.4g/cm at described three densification stage by the present invention
3, make charcoal/carbon/carbon brake disc final densities reach 1.80/cm
3above.
After tested, charcoal/carbon/carbon brake disc that prepared by the present invention can improve more than 50% work-ing life.
Embodiment
Embodiment 1
The present embodiment is a kind of processing method of charcoal/carbon/carbon brake disc, and detailed process comprises the following steps:
Step 1, heat-treats Carbon fibe precast body: Carbon fibe precast body is put into heat treatment furnace, is evacuated to≤1000Pa, be warming up to 2400 ~ 2600 DEG C to heat treatment furnace, is incubated and heat-treats for 5 ~ 10 hours.When temperature is at 1350 ~ 1450 DEG C, send argon shield; Obtain the precast body after thermal treatment.In the present embodiment, the temperature of heat treatment furnace is 2400 DEG C, and soaking time is 5h.
Step 2, CVI densification in early stage: the precast body after thermal treatment is put into CVI stove and carries out densification in early stage.The processing parameter of densification in early stage is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 2000 ~ 4000L/h.Until the density of precast body density is 1.30 ~ 1.40g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in early stage.In the present embodiment, the temperature of CVI stove is 900 DEG C, and gas discharge is 2000L/h.
Step 3, surface working: the mode added with machine is processed the charcoal after densification in early stage/carbon/carbon brake disc billet surface, single-sided process 1mm, to open the sealing of hole on surface, is conducive to CVI later stage densification.
Step 4, CVI densification in mid-term: the charcoal/carbon/carbon brake disc base substrate through densification in early stage is put into CVI stove and carries out densification in mid-term.The processing parameter of densification in mid-term is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 4000 ~ 6000 ls/h.Until the density of precast body density is 1.50 ~ 1.60g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in mid-term.In the present embodiment, the temperature of CVI stove is 900 DEG C, and gas discharge is 4000L/h.
Step 5, surface working: the mode added with machine is processed the charcoal after densification in mid-term/carbon/carbon brake disc billet surface, single-sided process 1mm, to open the sealing of hole on surface, is conducive to CVI later stage densification.
Step 6, CVI later stage densification: the charcoal/carbon/carbon brake disc base substrate through densification in mid-term is put into CVI stove and carries out later stage densification.The processing parameter of later stage densification is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 3000 ~ 5000 ls/h.Until the density of precast body density is 1.80/cm
3above; Obtain the charcoal/carbon/carbon brake disc base substrate through later stage densification.In the present embodiment, the temperature of CVI stove is 900 DEG C, and gas discharge is 3000L/h.
Step 7, finally processes; Charcoal/carbon/carbon brake disc base substrate is required finally to process according to product drawing, obtains charcoal/carbon/carbon brake disc.
Embodiment 2
The present embodiment is a kind of processing method of charcoal/carbon/carbon brake disc, and detailed process comprises the following steps:
Step 1, heat-treats Carbon fibe precast body: Carbon fibe precast body is put into heat treatment furnace, is evacuated to≤1000Pa, be warming up to 2400 ~ 2600 DEG C to heat treatment furnace, is incubated and heat-treats for 5 ~ 10 hours.When temperature is at 1350 ~ 1450 DEG C, send argon shield; Obtain the precast body after thermal treatment.In the present embodiment, the temperature of heat treatment furnace is 2600 DEG C, and soaking time is 10h.
Step 2, CVI densification in early stage: the precast body after thermal treatment is put into CVI stove and carries out densification in early stage.The processing parameter of densification in early stage is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 2000 ~ 4000L/h.Until the density of precast body density is 1.30 ~ 1.40g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in early stage.In the present embodiment, the temperature of CVI stove is 1100 DEG C, and gas discharge is 4000L/h.
Step 3, surface working: the mode added with machine is processed the charcoal after densification in early stage/carbon/carbon brake disc billet surface, single-sided process 1mm, to open the sealing of hole on surface, is conducive to CVI later stage densification.
Step 4, CVI densification in mid-term: the charcoal/carbon/carbon brake disc base substrate through densification in early stage is put into CVI stove and carries out densification in mid-term.The processing parameter of densification in mid-term is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 4000 ~ 6000 ls/h.Until the density of precast body density is 1.50 ~ 1.60g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in mid-term.In the present embodiment, the temperature of CVI stove is 1100 DEG C, and gas discharge is 6000L/h.
Step 5, surface working: the mode added with machine is processed the charcoal after densification in mid-term/carbon/carbon brake disc billet surface, single-sided process 1mm, to open the sealing of hole on surface, is conducive to CVI later stage densification.
Step 6, CVI later stage densification: the charcoal/carbon/carbon brake disc base substrate through densification in mid-term is put into CVI stove and carries out later stage densification.The processing parameter of later stage densification is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 3000 ~ 5000 ls/h.Until the density of precast body density is 1.80/cm
3above; Obtain the charcoal/carbon/carbon brake disc base substrate through later stage densification.In the present embodiment, the temperature of CVI stove is 1100 DEG C, and gas discharge is 5000L/h.
Step 7, finally processes; Charcoal/carbon/carbon brake disc base substrate is required finally to process according to product drawing, obtains charcoal/carbon/carbon brake disc.
Embodiment 3
The present embodiment is a kind of processing method of charcoal/carbon/carbon brake disc, and detailed process comprises the following steps:
Step 1, heat-treats Carbon fibe precast body: Carbon fibe precast body is put into heat treatment furnace, is evacuated to≤1000Pa, be warming up to 2400 ~ 2600 DEG C to heat treatment furnace, is incubated and heat-treats for 5 ~ 10 hours.When temperature is at 1350 ~ 1450 DEG C, send argon shield; Obtain the precast body after thermal treatment.In the present embodiment, the temperature of heat treatment furnace is 2500 DEG C, and soaking time is 8h.
Step 2, CVI densification in early stage: the precast body after thermal treatment is put into CVI stove and carries out densification in early stage.The processing parameter of densification in early stage is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 2000 ~ 4000L/h.Until the density of precast body density is 1.30 ~ 1.40g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in early stage.In the present embodiment, the temperature of CVI stove is 1000 DEG C, and gas discharge is 3000L/h.
Step 3, surface working: the mode added with machine is processed the charcoal after densification in early stage/carbon/carbon brake disc billet surface, single-sided process 1mm, to open the sealing of hole on surface, is conducive to CVI later stage densification.
Step 4, CVI densification in mid-term: the charcoal/carbon/carbon brake disc base substrate through densification in early stage is put into CVI stove and carries out densification in mid-term.The processing parameter of densification in mid-term is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 4000 ~ 6000 ls/h.Until the density of precast body density is 1.50 ~ 1.60g/cm
3.Obtain the charcoal/carbon/carbon brake disc base substrate through densification in mid-term.In the present embodiment, the temperature of CVI stove is 1000 DEG C, and gas discharge is 5000L/h.
Step 5, surface working: the mode added with machine is processed the charcoal after densification in mid-term/carbon/carbon brake disc billet surface, single-sided process 1mm, to open the sealing of hole on surface, is conducive to CVI later stage densification.
Step 6, CVI later stage densification: the charcoal/carbon/carbon brake disc base substrate through densification in mid-term is put into CVI stove and carries out later stage densification.The processing parameter of later stage densification is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 3000 ~ 5000 ls/h.Until the density of precast body density is 1.80/cm
3above; Obtain the charcoal/carbon/carbon brake disc base substrate through later stage densification.In the present embodiment, the temperature of CVI stove is 1000 DEG C, and gas discharge is 4000L/h.
Step 7, finally processes; Charcoal/carbon/carbon brake disc base substrate is required finally to process according to product drawing, obtains charcoal/carbon/carbon brake disc.
Claims (4)
1. a preparation method for charcoal/carbon/carbon brake disc, is characterized in that, detailed process is:
Step 1, heat-treats Carbon fibe precast body: Carbon fibe precast body is put into heat treatment furnace, is evacuated to≤1000Pa, be warming up to 2400 ~ 2600 DEG C to heat treatment furnace, is incubated and heat-treats for 5 ~ 10 hours; When temperature is at 1350 ~ 1450 DEG C, send argon shield; Obtain the precast body after thermal treatment;
Step 2, CVI densification in early stage: the precast body after thermal treatment is put into CVI stove and carries out densification in early stage; Until the density of precast body density is 1.30 ~ 1.40g/cm
3; Obtain the charcoal/carbon/carbon brake disc base substrate through densification in early stage;
Step 3, surface working: according to a conventional method surface working is carried out to the charcoal/carbon/carbon brake disc base substrate through densification in early stage obtained;
Step 4, CVI densification in mid-term: the charcoal/carbon/carbon brake disc base substrate through densification in early stage is put into CVI stove and carries out densification in mid-term; Until the density of precast body density is 1.50 ~ 1.60g/cm
3; Obtain the charcoal/carbon/carbon brake disc base substrate through densification in mid-term;
Step 5, surface working: according to a conventional method surface working is carried out to the charcoal/carbon/carbon brake disc base substrate through densification in early stage obtained;
Step 6, CVI later stage densification: the charcoal/carbon/carbon brake disc base substrate through densification in mid-term is put into CVI stove and carries out later stage densification; Until the density of precast body density is 1.80/cm
3above; Obtain the charcoal/carbon/carbon brake disc base substrate through later stage densification;
Step 7, finally processes: required finally to process according to product drawing by charcoal/carbon/carbon brake disc base substrate, obtain charcoal/carbon/carbon brake disc.
2. the preparation method of a kind of charcoal/carbon/carbon brake disc as claimed in claim 1, is characterized in that, the processing parameter of densification in early stage is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 2000 ~ 4000L/h.
3. the preparation method of a kind of charcoal/carbon/carbon brake disc as claimed in claim 1, it is characterized in that, the processing parameter of densification in mid-term is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 4000 ~ 6000 ls/h.
4. the preparation method of a kind of charcoal/carbon/carbon brake disc as claimed in claim 1, it is characterized in that, the processing parameter of later stage densification is: CVI stove furnace temperature is 900 ~ 1100 DEG C, CVI furnace pressure≤5KPa, gas discharge are 3000 ~ 5000 ls/h.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510555712.4A CN105198473A (en) | 2015-05-11 | 2015-09-02 | Preparation method of carbon/carbon brake disc |
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| CN201510236209 | 2015-05-11 | ||
| CN2015102362092 | 2015-05-11 | ||
| CN201510555712.4A CN105198473A (en) | 2015-05-11 | 2015-09-02 | Preparation method of carbon/carbon brake disc |
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| CN201510555712.4A Pending CN105198473A (en) | 2015-05-11 | 2015-09-02 | Preparation method of carbon/carbon brake disc |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111302821A (en) * | 2020-02-27 | 2020-06-19 | 深圳市晖耀电线电缆有限公司 | Preparation method of C/C composite material |
| CN111362714A (en) * | 2020-03-18 | 2020-07-03 | 德翼高科(杭州)科技有限公司 | Preparation method of carbon-ceramic brake disc |
| CN114249601A (en) * | 2021-11-15 | 2022-03-29 | 西安航空制动科技有限公司 | Novel carbon/carbon composite brake disc densification method |
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| CN1945048A (en) * | 2006-10-27 | 2007-04-11 | 上海应用技术学院 | Process for preparing carbon/carbon braking material for high speed train |
| CN103626511A (en) * | 2013-11-27 | 2014-03-12 | 西安航空制动科技有限公司 | Pretreatment method of carbon disc brake preform |
| CN104311093A (en) * | 2014-09-26 | 2015-01-28 | 内蒙古航天红岗机械有限公司 | Preparation method of C/C composite material |
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2015
- 2015-09-02 CN CN201510555712.4A patent/CN105198473A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1945048A (en) * | 2006-10-27 | 2007-04-11 | 上海应用技术学院 | Process for preparing carbon/carbon braking material for high speed train |
| CN103626511A (en) * | 2013-11-27 | 2014-03-12 | 西安航空制动科技有限公司 | Pretreatment method of carbon disc brake preform |
| CN104311093A (en) * | 2014-09-26 | 2015-01-28 | 内蒙古航天红岗机械有限公司 | Preparation method of C/C composite material |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111302821A (en) * | 2020-02-27 | 2020-06-19 | 深圳市晖耀电线电缆有限公司 | Preparation method of C/C composite material |
| CN111362714A (en) * | 2020-03-18 | 2020-07-03 | 德翼高科(杭州)科技有限公司 | Preparation method of carbon-ceramic brake disc |
| CN111362714B (en) * | 2020-03-18 | 2021-09-07 | 德翼高科(杭州)科技有限公司 | Preparation method of carbon-ceramic brake disc |
| CN114249601A (en) * | 2021-11-15 | 2022-03-29 | 西安航空制动科技有限公司 | Novel carbon/carbon composite brake disc densification method |
| CN114249601B (en) * | 2021-11-15 | 2022-10-28 | 西安航空制动科技有限公司 | Densification method of brake disc made of carbon/carbon composite material |
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Application publication date: 20151230 |