CN101671189B - Method for using domestic carbon fiber to prepare high-performance carbon-based composite material through rapid directional infiltration - Google Patents
Method for using domestic carbon fiber to prepare high-performance carbon-based composite material through rapid directional infiltration Download PDFInfo
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- CN101671189B CN101671189B CN2009100939470A CN200910093947A CN101671189B CN 101671189 B CN101671189 B CN 101671189B CN 2009100939470 A CN2009100939470 A CN 2009100939470A CN 200910093947 A CN200910093947 A CN 200910093947A CN 101671189 B CN101671189 B CN 101671189B
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Abstract
A method for using domestic carbon fiber to prepare high-performance carbon-based composite material through rapid directional infiltration includes five steps: step 1: putting the domestic carbon fiber preforms in nitric acid for oxidation treatment for 2h at the temperature of 80 DEG C; step 2: putting the domestic carbon fiber preforms in a rapid directional infiltration furnace and filling graphite gaskets of the same thickness among all the carbon fiber preforms; step 3: vacuumizing the body of the rapid directional infiltration furnace, eclectically heating a graphite sleeve and heating the carbon fiber preforms; step 4: introducing carbon source gas and diluent gas from the furnace bottom, mixing the carbon source gas and the diluent gas according to certain volume rate, extracting the gas from the furnace top and regulating the flow rate of gas according to the total weight of the preforms in the furnace; and step 5: gradually advancing the infiltration process of the preforms from the inside of the preforms to the outer surface and obtaining the high-performance carbon-based composite material after 120-200h of one-time infiltration, wherein in step 4, the pressure in the furnace is subject to certain requirement. The method shortens preparation period, improves the utilization rate of pyrolic carbon precursor and reduces the preparation cost of carbon-based composite materials.
Description
(1) technical field
The present invention relates to the slewing of a kind of charcoal fiber and ooze the long-pending method for preparing high-performance carbon-based composite material; Particularly relate to the slewing of a kind of domestic carbon fiber and ooze the long-pending method for preparing high-performance carbon-based composite material, belong to the quick preparing technical field of based composite material of carbon.
(2) background technology
The carbon fiber reinforced carbon based composites has just received widely since the accidental birth in U.S. CHANCE VOUGHT laboratory from 1958 and paying close attention to, and particularly has been widely used in fields such as Aeronautics and Astronautics as high temperature resistant with anti-abrasive material.Based composite material of carbon has the 26S Proteasome Structure and Function two-fold advantage; Can satisfy it as the secondary each item requirement of aircraft brake; Since 1973 were used for aircraft brake for the first time, existing civilian aircraft and the military aircraft more than 22 kinds more than 40 kinds in the whole world adopted carbon brake disc.Chemical vapor infiltration and liquid impregnation technology are the main method of preparation based composite material of carbon.Traditional isothermal and isobaric chemical vapor infiltration amasss (chemicalvapor infiltration; CVI) technology has processing parameter and controls easily; Advantages such as ability moulding complex geometric shapes goods, and widespread use suitability for industrialized production, but base substrate surperficial easily crust obstruction in densification process deposits; Need repeatedly interruption deposition to carry out mechanical workout and remove surface crust, thereby the densification cycle long (600～2000h).Resin, pitch liquid phase impregnation technology are carried out under normal pressure or decompression usually; Relying on increases dipping-charing-greying cycle index dense product; Make the goods of densification, dimensional stabilizing easily; But process efficiency is low and liquid is difficult to be impregnated in the micropore of base substrate and goes, and goods are prone to produce defectives such as tiny crack and layering.This has been developed high-pressure impregnation technology, but employed pressure is all more than 2MPa, complex process, high to equipment requirements, cause material cost to rise.At present, the charcoal fiber that adopts of domestic production based composite material of carbon is mainly bought from toray company and Japanese Dong Bang company.Along with the carbon fibers in China industrial production technology is day by day ripe, the domestic carbon fiber is produced problem in batches and is solved gradually, and the CCF model charcoal fibre density that light prestige group in Weihai, Shandong produces reaches 1.77g/cm
3, tensile strength reaches 3.95GPa, and modulus reaches 227GPa, and elongation at break reaches 1.84%, and the charcoal fibre property is suitable with the production T300 of toray company SERIES CARBON fibre property.But at present to by the research of China's domestic carbon fiber production based composite material of carbon seldom, domestic carbon fiber preforms slewing oozes that many key technical problems also do not solve in the long-pending process.
(3) summary of the invention
1, purpose: the purpose of this invention is to provide the slewing of a kind of charcoal fiber and ooze the long-pending method for preparing high-performance carbon-based composite material; Particularly provide the slewing of a kind of domestic carbon fiber to ooze the long-pending method for preparing high-performance carbon-based composite material; It is broken through domestic based composite material of carbon and prepares the Japanese product of main use charcoal fiber restriction in the process; A kind of long-pending quick preparing technique process of chemical vapor infiltration of suitable domestic carbon fiber reinforcement high-performance carbon-based composite material is provided, prepares density in 200 hours fast and reach 1.70～1.80g/cm
3High-performance carbon-based composite material, it has shortened preparation cycle, has improved pyrolytic carbon precursor utilization ratio, has reduced the high-performance carbon-based composite material preparation cost significantly.
2, technical scheme: the long-pending method that prepare high-performance carbon-based composite material is oozed in the slewing of a kind of domestic carbon fiber of the present invention, and it is as shown in Figure 1 that its chemical vapor infiltration amasss equipment, and the implementation process of domestic carbon fiber is mainly comprised the following steps:
Step 1: the charcoal fiber preform was put into 80 ℃ of oxide treatment of nitric acid 2 hours;
Step 2: the charcoal fiber preform is put into slewing ooze long-pending stove, be encased inside the Graphite pad of uniform thickness between each charcoal fiber preform;
Step 3: slewing is oozed long-pending furnace body and is vacuumized electrically heated graphite sleeve and charcoal fiber preform;
Step 4: feed carbon-source gas and diluents, gas is mixed with certain volume ratio, and gas feeds from furnace bottom, and furnace roof is extracted out, and its flow is according to charcoal fiber preform gross weight adjustment in the stove of packing into, and the pressure that oozes in the long-pending stove is 2kPa～10kPa;
Step 5: the long-pending process of oozing of charcoal fiber preform advances to outside surface from charcoal fiber preform inside gradually, disposablely oozes long-pendingly through 120～200 hours, can make high-performance carbon-based composite material, and density reaches 1.70g/cm
3～1.80g/cm
3
Wherein, nitric acid is that concentration is 67%～70% industrial nitric acid in the said step 1;
Wherein, the thickness of the Graphite pad in the said step 2 is 1.5mm～5mm, and pad is placed in charcoal fiber preform outer rim, equidistant placement;
Wherein, once can lay charcoal fiber preform 30 dishes～50 dishes in the said step 2;
Wherein, the initial density of charcoal fiber is 0.4g/cm in the said step 2
3～0.6g/cm
3
Wherein, during electrically heated, control charcoal fiber preform peripheral temperature reaches 1100 ℃～1150 ℃ in the said step 3, and graphite sleeve core temperature reaches 1050 ℃～1100 ℃;
Wherein, oozing long-pending furnace body in the said step 3 is evacuated to-0.1MPa;
Wherein, the carbon-source gas of selecting for use in the said step 4 is Sweet natural gas and propane gas mixture, and diluents is a hydrogen;
Wherein, the volume ratio of Sweet natural gas and propane is 7～9: 1 in the said step 4;
Wherein, the volume ratio of hydrogen and propane is 1～3: 1 in the said step 4;
Wherein, flow is meant that according to precast body gross weight adjustment in the stove of packing into control per hour required carbon-source gas Sweet natural gas of per kilogram precast body and propane gross weight are 50g～100g in the said step 4;
3, advantage and effect: the present invention compared with prior art, its advantage and effect are:
(1) the present invention adopts domestic carbon fiber preforms to prepare the high-performance high-performance carbon-based composite material; Domestic carbon fiber price is lower than Japan's product charcoal fiber at present; Thereby select for use the domestic carbon fiber to reduce the preparation cost of high-performance carbon-based composite material, select for use domestic carbon fiber production high-performance carbon-based composite material to have great importance simultaneously.
(2) adopt Sweet natural gas and propane gas mixture as carbon-source gas; Hydrogen is as diluents, can realize oozing to the slewing of outside from precast body inside long-pending, avoided based composite material of carbon surface crust in preparation process fast; Improve the utilization ratio of carbon-source gas, often reached 30%～60%; The appropriate design of frock has effectively been avoided gas hold-up in the stove, has suppressed the sooty generation.
(3) frock can design according to domestic carbon fiber reinforcement high-performance carbon-based composite material structural requirement again in the stove, can satisfy the different structure based composite material of carbon and prepare requirement.
(4) adopt the present invention's technology, can prepare density and reach 1.70～1.80g/cm in 200 hours
3High-performance carbon-based composite material, pyrolytic carbon is mainly rough layer.Compare with traditional isothermal process, preparation technology shortens in the cycle greatly, has reduced the preparation cost of product.
(4) description of drawings
Pneumatosis flow control device structural representation is oozed in the slewing of Fig. 1 high-performance carbon-based composite material
The scheme of installation of Fig. 2 pad
Nomenclature is following among the figure:
The 1-air outlet; 2-oozes long-pending furnace wall; 3-heating graphite sleeve;
4-graphite cover plate; The 5-Graphite pad; The 6-domestic carbon fiber preforms;
7-graphite guiding device; The 8-through hole; 9-graphite plectane;
10-graphite plectane with holes; The 11-pad; The 12-graphite cylinder;
The 13-inlet mouth.
(5) embodiment
The long-pending method for preparing high-performance carbon-based composite material is oozed in the slewing of a kind of domestic carbon fiber of the present invention, and this method specific embodiment is following:
The long-pending equipment of its chemical vapor infiltration is as shown in Figure 1, and method of the present invention is oozed in the pneumatosis flow control device in this high-performance carbon-based composite material slewing and carried out.Said charcoal fiber adopts the domestic carbon fiber, implements with the domestic carbon fiber.
The long-pending method for preparing high-performance carbon-based composite material is oozed in the slewing of a kind of domestic carbon fiber of the present invention, and these method concrete steps are following:
Step 1: it is 80 ℃ of oxide treatment of 70% nitric acid 2 hours that the charcoal fiber preform is put into concentration.
Step 2: with charcoal fiber preform 6, external diameter is 420mm, and internal diameter is 250mm, and thickness is 24mm, and initial density is 0.45g/cm
3, steadily be placed on the graphite plectane 9, open with Graphite pad 5 pad between the every precast body, 40 of the graphite precast bodies of once packing into, and cover graphite cover plate 4.The placement location of Graphite pad 5 is as shown in Figure 2, and the thickness of Graphite pad 5 is 1.5mm.
Step 3: electrically heated graphite sleeve 3 and charcoal fiber preform 6, its graphite sleeve 3 core temperatures reach 1090 ℃.
Step 4: the mixed gas and the diluents hydrogen of carbon-source gas Sweet natural gas and propane are oozed long-pending stove through inlet mouth 13 feedings; The total flux of carbon-source gas is looked the total flux of precast body and is decided; The per kilogram precast body per hour feeds carbon-source gas 60g; The volume ratio of Sweet natural gas and propane is 8/1, and the volume ratio of propane and diluents hydrogen is 1/1, and the furnace pressure that long-pending stove is oozed in control is 5kPa.
Step 5: oozed long-pending 180 hours, the density of based composite material of carbon just can reach 1.73g/cm
3～1.78g/cm
3
Embodiment 2
The long-pending equipment of its chemical vapor infiltration is as shown in Figure 1, and method of the present invention is oozed in the pneumatosis flow control device in this high-performance carbon-based composite material slewing and carried out.Said charcoal fiber adopts the domestic carbon fiber, implements with the domestic carbon fiber.
The long-pending method for preparing high-performance carbon-based composite material is oozed in the slewing of domestic carbon fiber, and these method concrete steps are following:
Step 1: it is 80 ℃ of oxide treatment of 70% nitric acid 2 hours that domestic carbon fiber preforms is put into concentration.
Step 2: with domestic carbon fiber preforms 6, external diameter is 45mm, and internal diameter is 280mm, and thickness is 23mm, and initial density is 0.55g/cm
3, steadily be placed on the graphite plectane 9, open with Graphite pad 5 pad between the every precast body, 40 of the graphite precast bodies of once packing into, and cover graphite cover plate 4.The placement location of Graphite pad 5 is as shown in Figure 2, and the thickness of Graphite pad 5 is 1.5mm.
Step 3: electrically heated graphite sleeve 3 and charcoal fiber preform 6, its graphite sleeve 3 core temperatures reach 1090 ℃.
Step 4: the mixed gas and the diluents hydrogen of carbon-source gas Sweet natural gas and propane are oozed long-pending stove through inlet mouth 13 feedings; The total flux of carbon-source gas is looked the total flux of precast body and is decided; The per kilogram precast body per hour feeds carbon-source gas 50g; The volume ratio of Sweet natural gas and propane is 8/1, and the volume ratio of propane and diluents hydrogen is 1/2, and the furnace pressure that long-pending stove is oozed in control is 5kPa.
Step 5: oozed long-pending 200 hours, the density of based composite material of carbon just can reach 1.71g/cm
3～1.78g/cm
3
Claims (8)
1. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber slewing, and it is characterized in that: these method concrete steps are following:
Step 1: the charcoal fiber preform was put into 80 ℃ of oxide treatment of nitric acid 2 hours;
Step 2: the charcoal fiber preform is put into slewing ooze long-pending stove, be encased inside the Graphite pad of uniform thickness between each charcoal fiber preform;
Step 3: slewing is oozed long-pending furnace body and is vacuumized electrically heated graphite sleeve and charcoal fiber preform;
Step 4: feed carbon-source gas and diluents, gas is mixed with certain volume ratio, and gas feeds from furnace bottom, and furnace roof is extracted out, and its flow is according to precast body gross weight adjustment in the stove of packing into, and the pressure that oozes in the long-pending stove is 2kPa～10kPa;
Step 5: the long-pending process of oozing of charcoal fiber preform advances to outside surface from charcoal fiber preform inside gradually, disposablely oozes long-pendingly through 120～200 hours, can make high-performance carbon-based composite material, and density reaches 1.70g/cm
3～1.80g/cm
3
Wherein, in the electrically heated described in the step 3, control charcoal fiber preform peripheral temperature reaches 1100 ℃～1150 ℃, and graphite sleeve core temperature reaches 1050 ℃～1100 ℃.
2. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing, it is characterized in that: at the nitric acid described in the step 1, be the industrial nitric acid of concentration 67%～70%.
3. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing; It is characterized in that: at the Graphite pad of the uniform thickness described in the step 2; Its thickness is 1.5mm～5mm, is placed in the equidistant placement of precast body outer rim.
4. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing; It is characterized in that: long-pending stove is oozed in the slewing that the charcoal fiber preform is put into described in the step 2, once can lay charcoal fiber preform 30 dishes～50 dishes.
5. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing, and it is characterized in that: at the charcoal fiber preform described in the step 2 step, its initial density is 0.4g/cm
3～0.6g/cm
3
6. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing, it is characterized in that: ooze long-pending furnace body in the slewing described in the step 3 and vacuumize, its vacuum is evacuated to-0.1MPa.
7. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing, and it is characterized in that: at the carbon-source gas described in the step 4 is Sweet natural gas and propane gas mixture, and diluents is a hydrogen; Described gas mixed volume ratio is: the volume ratio of Sweet natural gas and propane is 7～9: 1; The volume ratio of hydrogen and propane is 1～3: 1.
8. the long-pending method for preparing high-performance carbon-based composite material is oozed in domestic carbon fiber according to claim 1 slewing; It is characterized in that: precast body gross weight adjustment in the basis of the flow described in the step 4 is packed stove into is meant that control per hour required carbon-source gas Sweet natural gas of per kilogram precast body and propane gross weight are 50g～100g.
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| CN102021648B (en) * | 2011-01-10 | 2012-04-11 | 湖南金博复合材料科技有限公司 | Guide cylinder antioxidation coating and preparation method thereof |
| CN104446585B (en) * | 2013-09-24 | 2018-04-17 | 江门市硕普科技开发有限公司 | The method that batch quickly prepares high-density carbon/carbon composite material |
| CN109400198A (en) * | 2018-12-13 | 2019-03-01 | 上海康碳复合材料科技有限公司 | A kind of carbon/carbon (pottery) composite material brake disc Preparation equipment and preparation method thereof based on quick sedimentation process |
| CN111072397A (en) * | 2019-12-03 | 2020-04-28 | 北京优材百慕航空器材有限公司 | Carbon/carbon composite material brake disc and preparation method thereof |
| CN112645727B (en) * | 2020-12-29 | 2022-12-20 | 湖南博云新材料股份有限公司 | Method for producing carbon-carbon composite material blank for airplane brake disc |
| CN113601686A (en) * | 2021-07-16 | 2021-11-05 | 内蒙古航天红岗机械有限公司 | Tool for preparing C/C composite material by liquid-phase impregnation and furnace charging method |
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| CA2205087A1 (en) * | 1994-11-16 | 1996-05-23 | Mark J. Purdy | Pressure gradient cvi/cvd apparatus, process and product |
| CN1350959A (en) * | 2000-10-27 | 2002-05-29 | 西安兰空航空设备公司 | Method and equipment for high-speed gas-phase carbon deposition of braking carbon disk for aircraft |
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Inventor after: Luo Ruiying Inventor after: Zhang You Inventor after: Zhang Jincao Inventor after: Li Jinsong Inventor after: Yan Ying Inventor after: Zhang Yunfeng Inventor before: Luo Ruiying Inventor before: Zhang Jincao Inventor before: Li Jinsong Inventor before: Yan Ying Inventor before: Zhang Yunfeng |
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Free format text: CORRECT: INVENTOR; FROM: LUO RUIYING ZHANG JINGCAO LI JINSONG YAN YING ZHANG YUNFENG TO: LUO RUIYING ZHANG YOU ZHANG JINGCAO LI JINSONG YAN YING ZHANG YUNFENG |