CN102344302A - Preparation method of carbon/carbon composite material surface SiC/mullite coating - Google Patents
Preparation method of carbon/carbon composite material surface SiC/mullite coating Download PDFInfo
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- CN102344302A CN102344302A CN2011101632768A CN201110163276A CN102344302A CN 102344302 A CN102344302 A CN 102344302A CN 2011101632768 A CN2011101632768 A CN 2011101632768A CN 201110163276 A CN201110163276 A CN 201110163276A CN 102344302 A CN102344302 A CN 102344302A
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Abstract
The invention discloses a preparation method of a carbon/carbon composite material surface SiC/mullite coating. The preparation method comprises the following steps of 1, carrying out burnishing, polishing, cleaning and drying of a sample, 2, mixing Si powder, C powder and Al2O3 powder, carrying out ball milling, and embedding the sample obtained by the step 1 with the mixed powder to form a SiC internal coating, 3, carrying out ball milling and screening of mullite powder, spraying the screened mullite powder on the surface of the sample with the SiC internal coating, maintaining the sprayed sample in a high-temperature oxidation environment to obtain a carbon/carbon composite material sample with a SiC/mullite coating, and then taking the carbon/carbon composite material sample with a SiC/mullite coating out. The preparation method solves the problem that a carbon/carbon composite material matrix does not match with thermal expansion coefficients of a mullite outer coating. Through the preparation method, an outer coating has a compact and complete structure, does not produce obvious cracks and can combine with a SiC internal coating well. The preparation method can control coating thickness through adjustment of technological parameters and has high coating preparation efficiency.
Description
Technical field
The present invention relates to a kind of carbon/carbon composite material oxidation-proof coating preparation method.
Background technology
Carbon/carbon composite has low density, high specific strength, high ratio modulus, have stable high-temperature performance and intensity raises and advantages such as rising with temperature, becomes the important materials in field such as aerospace industry.But carbon/carbon composite is in the rapid oxidation of generation in the oxygen atmosphere that has that is higher than 450 ℃; And rate of oxidation raises and increases sharply along with temperature; This big limitations its as the application of high-temperature structural material under the high temperature aerobic environment, inoxidzable coating is one of effective measure that address this problem.The preparation inoxidzable coating is one of effective way that solves the carbon/carbon composite oxidation.
Document 1 " S.N.Basu; T.Kulkarni; H.Z.Wang; V.K.Sarin; Functionally graded chemical vapor deposited mullite environmental barrier coatings for Si-based ceramics; J.Eur.Ceram.Soc.28 (2008) 437-445 " has been introduced a kind of method of utilizing the chemical vapor deposition (CVD) method to prepare crystallization mullite (mullite) coating at the SiC matrix surface; The coating structure of preparation is evenly fine and close, under 1300 ℃, can prevent the oxidation of SiC matrix effectively.
Document 2 " J.F.Huang; H.J.Li; X.R.Zeng; X.B.Xiong; K.Z.Li; Influence of preparation technology on the microstructure and anti-oxidation property of SiC-Al2O3-mullite multi-coatings for carbon/carbon composites, Appl.Surf.Sci.252 (2006) 4244-4249 " has been introduced a kind of two step of employing embedding techniques at carbon/carbon composite surface preparation SiC-Al
2O
3The method of-mullite laminated coating, the coating of preparation can provide effective protection against oxidation to carbon/carbon composite: through 1600 ℃ of oxidations 81 hours, rate of weight loss only was 2.3%.
Yet still there is certain weak point in above-mentioned coating production.Chemical Vapor deposition process, its preparation coating process is complicated, and the cycle is long, the cost height, and coating and substrate combinating strength are not high enough, and this will make coating under high temperature to room temperature thermal shock condition, come off easily, cause the coating ultimate failure; Coat-thickness and the homogeneity of utilizing entrapping method to obtain are difficult to control, and process repeatability is relatively poor, and higher coating preparation temperature is bigger to the mechanical property influence that C/C meets material matrix.
Summary of the invention
Prior art is prone to cause coating to lose efficacy or the deficiency of complex process in order to overcome; The present invention provides the preparation method of a kind of carbon/carbon composite surface SiC/mullite inoxidzable coating; Coating combines good; Can regulate processing parameter control coating thickness in the spraying process, and coating preparation efficient is high.
The technical solution adopted for the present invention to solve the technical problems comprises the steps:
1. the carbon/carbon composite sample is carried out sanding and polishing earlier, be placed on then in the dehydrated alcohol, adopt ultrasonic cleaner to clean 20-30 minute, the oven dry back is subsequent use down in 80-100 ℃ to put into baking oven;
2. take by weighing the Si powder of 70-80wt.%, the C powder of 15-20wt.%, the Al of 5-10wt.% respectively
2O
3Powder obtained batch mixing after mixing and ball milling 1-3 hour; The batch mixing of half is put into plumbago crucible, put into subsequent use carbon/carbon composite sample then, the batch mixing that adds second half again covers the carbon/carbon composite sample, adds the plumbago crucible lid; The plumbago crucible that installs is put into the vertical vacuum furnace of graphite heater, after being evacuated to 1-10Pa, with 5-10 ℃ of min
-1Heat-up rate furnace temperature is risen to 1800-2200 ℃, be incubated 1-3 hour, powered-down is lowered the temperature naturally subsequently, promptly obtains the SiC undercoat at C/C matrix material specimen surface;
3. mullite powder ball milling after 1-3 hour, is crossed 200 and 300 mesh sieves successively, the powder of getting between the 200-300 order is made the spraying powder;
4. adopt the supersonic speed plasma spraying equipment that mullite is sprayed spraying of powdery row material to having the internally coated carbon/carbon composite specimen surface of SiC; Obtain the mullite external coating (EC); The processing parameter that spraying process adopts is following: operating voltage is 390-410V; Working current is 130-150A; Main gas (Ar) air pressure is 1.0-1.4MPa, and main gas (Ar) flow is 5.8-6.4m
3H
-1, auxilliary gas (H
2) air pressure is 0.8-1.2MPa, auxilliary gas (H
2) flow is 1.8-2.2m
3H
-1, powder sending quantity is 10-20Lmin
-1, spray distance is 80-100mm; Finally make coat-thickness 100-120 μ m.
5. for obtaining mullite crystallization coating; SiC/mullite coating carbon/carbon composite sample after the spraying is put into retort furnace; Take out after 1-2 hour in insulation under the 1300-1500 ℃ of high-temperature oxidation environment, promptly obtain SiC/mullite coating carbon/carbon composite sample.
The invention has the beneficial effects as follows:, alleviated the thermal expansivity mismatch problem of matrix of carbon/carbon composite materials and mullite external coating (EC) owing to adopt SiC as undercoat; Compare with method described in the document 2 with document 1; Adopt the mullite external coating (EC) compact structure of supersonic speed plasma spraying technology preparation complete; There is not obvious crackle; Combine well with the SiC undercoat; Can pass through in the spraying process to regulate processing parameter control coating thickness such as powder sending quantity, spraying number of times, and coating preparation efficient is high.Therefore; Adopt the supersonic speed plasma spraying technology to improve the deficiency of CVD, entrapping method etc. effectively; The SiC/mullite coating of preparation can provide effective high-temp antioxidizing protection to carbon/carbon composite; 1500 ℃ of oxidations after 98.5 hours rate of weight loss be 2.57%, 1600 ℃ of oxidation after 47 hours rate of weight loss be 1.67%.
Below in conjunction with accompanying drawing and embodiment the present invention is further specified.
Description of drawings
Fig. 1 prepares SiC/mullite coating process general flow chart for the inventive method.
Fig. 2 (a) is the prepared mullite coatingsurface SEM photo of the inventive method, and Fig. 2 (b) is the prepared mullite coating section S EM photo of the inventive method.
Fig. 3 is prepared 1500 ℃ and the 1600 ℃ oxidation weight loss curves of SiC/mullite coating carbon/carbon composite sample of the inventive method.
Embodiment
Embodiment 1:
With the carbon/carbon composite sample; Polish with 100# sand paper earlier and remove corner angle, use 200# and 500# sand paper to carry out the fine grinding polishing more respectively, be placed in the dehydrated alcohol at last; Adopt ultrasonic cleaner to clean 20 minutes, it is subsequent use to put into 80 ℃ of dry backs of baking oven.
Take by weighing the Si powder of 70wt.%, the C powder of 20wt.%, the Al of 10wt.% respectively
2O
3Powders such as powder, mixing and ball milling 1 hour; Half batch mixing is put into plumbago crucible, put into subsequent use carbon/carbon composite sample then, with remaining second half batch mixing the carbon/carbon composite sample is covered again, add the plumbago crucible lid; The plumbago crucible that installs is put into the vertical vacuum furnace of graphite heater, after being evacuated to 1Pa, with 5 ℃ of min
-1Heat-up rate furnace temperature is risen to 1800 ℃, be incubated 3 hours, powered-down is lowered the temperature naturally subsequently, whole process using Ar gas shiled obtains the SiC undercoat at C/C matrix material specimen surface.
Mullite powder ball milling after 1 hour, is crossed 200 and 300 mesh sieves successively, and the powder of getting between the 200-300 order is made the spraying powder;
Adopt HEPJet-100 supersonic speed plasma spraying equipment that mullite is sprayed spraying of powdery row material to having the internally coated carbon/carbon composite specimen surface of SiC; Obtain the mullite external coating (EC); The processing parameter that spraying process adopts is following: operating voltage is 390V; Working current is 150A; Main gas (Ar) air pressure is 1.0MPa, and main gas (Ar) flow is 5.8m
3H
-1, auxilliary gas (H
2) air pressure is 0.8MPa, auxilliary gas (H
2) flow is 1.8m
3H
-1, powder sending quantity is 10Lmin
-1, spray distance is 80mm;
SiC/mullite coating carbon/carbon composite sample after the spraying is put into retort furnace,, promptly obtain SiC/mullite coating carbon/carbon composite sample with the insulation taking-up after 2 hours down of 1300 ℃ of well-oxygenated environments.
Embodiment 2:
With the carbon/carbon composite sample; Polish with 100# sand paper earlier and remove corner angle, use 200# and 500# sand paper to carry out the fine grinding polishing more respectively, be placed in the dehydrated alcohol at last; Adopt ultrasonic cleaner to clean 30 minutes, it is subsequent use to put into 100 ℃ of dry backs of baking oven.
Take by weighing the Si powder of 80wt.%, the C powder of 15wt.%, the Al of 5wt.% respectively
2O
3Powders such as powder, mixing and ball milling 2 hours; Half batch mixing is put into plumbago crucible, put into subsequent use carbon/carbon composite sample then, with remaining second half batch mixing the carbon/carbon composite sample is covered again, add the plumbago crucible lid; The plumbago crucible that installs is put into the vertical vacuum furnace of graphite heater, after being evacuated to 10Pa, with 10 ℃ of min
-1Heat-up rate furnace temperature is risen to 2000 ℃, be incubated 2 hours, powered-down is lowered the temperature naturally subsequently, whole process using Ar gas shiled obtains the SiC undercoat at C/C matrix material specimen surface.
Mullite powder ball milling after 3 hours, is crossed 200 and 300 mesh sieves successively, and the powder of getting between the 200-300 order is made the spraying powder;
Adopt HEPJet-100 supersonic speed plasma spraying equipment that mullite is sprayed spraying of powdery row material to having the internally coated carbon/carbon composite specimen surface of SiC; Obtain the mullite external coating (EC); The processing parameter that spraying process adopts is following: operating voltage is 400V; Working current is 140A; Main gas (Ar) air pressure is 1.2MPa, and main gas (Ar) flow is 6.1m
3H
-1, auxilliary gas (H
2) air pressure is 1.0MPa, auxilliary gas (H
2) flow is 2.0m
3H
-1, powder sending quantity is 15Lmin
-1, spray distance is 90mm;
SiC/mullite coating carbon/carbon composite sample after the spraying is put into retort furnace,, promptly obtain SiC/mullite coating carbon/carbon composite sample with the insulation taking-up after 2 hours down of 1400 ℃ of well-oxygenated environments.
SiC/mullite coating carbon/carbon composite sample is carried out anti-oxidation experiment test under 1500 ℃ of air ambients, the result shows that through oxidation in 98.5 hours, the sample rate of weight loss only was 2.57%.
Embodiment 3:
With the carbon/carbon composite sample; Polish with 100# sand paper earlier and remove corner angle, use 200# and 500# sand paper to carry out the fine grinding polishing more respectively, be placed in the dehydrated alcohol at last; Adopt ultrasonic cleaner to clean 25 minutes, it is subsequent use to put into 90 ℃ of dry backs of baking oven.
Take by weighing the Si powder of 75wt.%, the C powder of 17.5wt.%, the Al of 7.5wt.% respectively
2O
3Powders such as powder, mixing and ball milling 3 hours; Half batch mixing is put into plumbago crucible, put into subsequent use carbon/carbon composite sample then, merely mixing with remaining second half again, material adds the plumbago crucible lid with the covering of carbon/carbon composite sample; The plumbago crucible that installs is put into the vertical vacuum furnace of graphite heater, after being evacuated to 5Pa, with 7.5 ℃ of min
-1Heat-up rate furnace temperature is risen to 2200 ℃, be incubated 1 hour, powered-down is lowered the temperature naturally subsequently, whole process using Ar gas shiled obtains the SiC undercoat at C/C matrix material specimen surface.
Mullite powder ball milling after 2 hours, is crossed 200 and 300 mesh sieves successively, and the powder of getting between the 200-300 order is made the spraying powder;
Adopt HEPJet-100 supersonic speed plasma spraying equipment that mullite is sprayed spraying of powdery row material to having the internally coated carbon/carbon composite specimen surface of SiC; Obtain the mullite external coating (EC); The processing parameter that spraying process adopts is following: operating voltage is 410V; Working current is 130A; Main gas (Ar) air pressure is 1.4MPa, and main gas (Ar) flow is 6.4m
3H
-1, auxilliary gas (H
2) air pressure is 1.2MPa, auxilliary gas (H
2) flow is 2.2m
3H
-1, powder sending quantity is 20Lmin
-1, spray distance is 100mm;
SiC/mullite coating carbon/carbon composite sample after the spraying is put into retort furnace,, promptly obtain SiC/mullite coating carbon/carbon composite sample with the insulation taking-up after 1 hour down of 1500 ℃ of well-oxygenated environments.
SiC/mullite coating carbon/carbon composite sample is carried out anti-oxidation experiment test under 1600 ℃ of air ambients, the result shows that through oxidation in 47 hours, the sample rate of weight loss only was 1.67%.
Claims (1)
1. the preparation method of a carbon/carbon composite surface SiC/mullite coating is characterized in that comprising the steps:
1) the carbon/carbon composite sample is carried out sanding and polishing earlier, be placed on then in the dehydrated alcohol, adopt ultrasonic cleaner to clean 20-30 minute, the oven dry back is subsequent use down in 80-100 ℃ to put into baking oven;
2) take by weighing the Si powder of 70-80wt.%, the C powder of 15-20wt.%, the Al of 5-10wt.% respectively
2O
3Powder obtained batch mixing after mixing and ball milling 1-3 hour; The batch mixing of half is put into plumbago crucible, put into subsequent use carbon/carbon composite sample then, the batch mixing that adds second half again covers the carbon/carbon composite sample, adds the plumbago crucible lid; The plumbago crucible that installs is put into the vertical vacuum furnace of graphite heater, after being evacuated to 1-10Pa, with 5-10 ℃ of min
-1Heat-up rate furnace temperature is risen to 1800-2200 ℃, be incubated 1-3 hour, powered-down is lowered the temperature naturally subsequently, promptly obtains the SiC undercoat at C/C matrix material specimen surface;
3) mullite powder ball milling after 1-3 hour, is crossed 200 and 300 mesh sieves successively, the powder of getting between the 200-300 order is made the spraying powder;
4) adopt the supersonic speed plasma spraying equipment that mullite is sprayed spraying of powdery row material to having the internally coated carbon/carbon composite specimen surface of SiC; Obtain the mullite external coating (EC); The processing parameter that spraying process adopts is following: operating voltage is 390-410V; Working current is 130-150A; Ar air pressure is 1.0-1.4MPa, and the Ar flow is 5.8-6.4m
3H
-1, H
2Air pressure is 0.8-1.2MPa, H
2Flow is 1.8-2.2m
3H
-1, powder sending quantity is 10-20Lmin
-1, spray distance is 80-100mm; Finally make coat-thickness 100-120 μ m;
5) for obtaining mullite crystallization coating; SiC/mullite coating carbon/carbon composite sample after the spraying is put into retort furnace; Take out after 1-2 hour in insulation under the 1300-1500 ℃ of high-temperature oxidation environment, promptly obtain SiC/mullite coating carbon/carbon composite sample.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102584338A (en) * | 2012-02-20 | 2012-07-18 | 西北工业大学 | Preparation method of composite biological coating on surface of carbon/carbon composite material |
| CN102746028A (en) * | 2012-05-26 | 2012-10-24 | 苏州宏久航空防热材料科技有限公司 | Oxide-particle-embedded silicon carbide coating and preparation method thereof |
| CN105461357A (en) * | 2015-11-18 | 2016-04-06 | 中南大学 | A charcoal/charcoal composite material ablation-resisting coating and a preparing process thereof |
| CN105541405A (en) * | 2015-12-25 | 2016-05-04 | 苏州宏久航空防热材料科技有限公司 | Method for uniformly depositing SiC coating on surface of carbon material in graphite heater heating furnace |
| CN106631173A (en) * | 2017-01-16 | 2017-05-10 | 西北工业大学 | C/C composite material SiC-Y2Hf2O7 compound coating and preparation method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101565328A (en) * | 2009-05-26 | 2009-10-28 | 西北工业大学 | Method for preparing carbon/carbon composite material antioxidation coating layer |
| CN101786906A (en) * | 2009-12-14 | 2010-07-28 | 西北工业大学 | Preparation method of anti-oxidation SiC/mullite-Si-Al2O3 composite coating on surface of C/C composite material |
-
2011
- 2011-06-16 CN CN2011101632768A patent/CN102344302A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101565328A (en) * | 2009-05-26 | 2009-10-28 | 西北工业大学 | Method for preparing carbon/carbon composite material antioxidation coating layer |
| CN101786906A (en) * | 2009-12-14 | 2010-07-28 | 西北工业大学 | Preparation method of anti-oxidation SiC/mullite-Si-Al2O3 composite coating on surface of C/C composite material |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102584338A (en) * | 2012-02-20 | 2012-07-18 | 西北工业大学 | Preparation method of composite biological coating on surface of carbon/carbon composite material |
| CN102584338B (en) * | 2012-02-20 | 2013-08-28 | 西北工业大学 | Preparation method of composite biological coating on surface of carbon/carbon composite material |
| CN102746028A (en) * | 2012-05-26 | 2012-10-24 | 苏州宏久航空防热材料科技有限公司 | Oxide-particle-embedded silicon carbide coating and preparation method thereof |
| CN105461357A (en) * | 2015-11-18 | 2016-04-06 | 中南大学 | A charcoal/charcoal composite material ablation-resisting coating and a preparing process thereof |
| CN105461357B (en) * | 2015-11-18 | 2018-02-13 | 中南大学 | A kind of carbon/carbon composite ablative cork coatings and its preparation technology |
| CN105541405A (en) * | 2015-12-25 | 2016-05-04 | 苏州宏久航空防热材料科技有限公司 | Method for uniformly depositing SiC coating on surface of carbon material in graphite heater heating furnace |
| CN105541405B (en) * | 2015-12-25 | 2018-03-23 | 苏州宏久航空防热材料科技有限公司 | The method of carbon materials surface uniform deposition SiC coatings in graphite heater stove |
| CN106631173A (en) * | 2017-01-16 | 2017-05-10 | 西北工业大学 | C/C composite material SiC-Y2Hf2O7 compound coating and preparation method thereof |
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Application publication date: 20120208 |
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