CN109467457B - Composition, high-emissivity antioxidant coating prepared from composition and used for porous carbon fiber heat-insulating material surface and preparation method of high-emissivity antioxidant coating - Google Patents

Composition, high-emissivity antioxidant coating prepared from composition and used for porous carbon fiber heat-insulating material surface and preparation method of high-emissivity antioxidant coating Download PDF

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CN109467457B
CN109467457B CN201811595424.1A CN201811595424A CN109467457B CN 109467457 B CN109467457 B CN 109467457B CN 201811595424 A CN201811595424 A CN 201811595424A CN 109467457 B CN109467457 B CN 109467457B
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carbon fiber
porous carbon
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coating
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CN109467457A (en
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张如炳
叶长收
侯先波
安志民
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Beijing Jiaotong University
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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
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
    • 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
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/50—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with inorganic materials
    • C04B41/5053—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with inorganic materials non-oxide ceramics
    • C04B41/5062—Borides, Nitrides or Silicides
    • C04B41/5071—Silicides
    • 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
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
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    • C04B41/87—Ceramics

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Abstract

The invention relates to a composition, a porous carbon fiber heat-insulating material surface high-emissivity antioxidant coating prepared from the composition and a preparation method of the coating. The composition comprises the following components: transition metal boride, refractory metal silicide, silicon carbide powder, polycarbosilane and cerium oxide. The preparation method comprises the following steps: preparing slurry; coating the slurry onto a porous carbon fiber thermal insulation material; and drying, heat treating and sintering the porous carbon fiber heat-insulating material coated with the slurry in sequence to obtain the high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material. The composition is applied to the preparation of the coating, can reduce the sintering temperature, and the prepared coating has the advantages of higher emissivity, lower high-temperature thermal conductivity and good ultrahigh temperature stability, and is expected to be applied to a thermal protection system of a hypersonic aircraft.

Description

Composition, high-emissivity antioxidant coating prepared from composition and used for porous carbon fiber heat-insulating material surface and preparation method of high-emissivity antioxidant coating
Technical Field
The invention relates to the technical field of ultra-high temperature heat-insulating materials, in particular to a composition, a porous carbon fiber heat-insulating material surface high-emissivity antioxidant coating prepared from the composition and a preparation method of the coating.
Background
Carbon fiber-bonded carbon fiber composites are a class of low-density, high-porosity carbon/carbon composites. It has excellent performances of high porosity, low density, low thermal conductivity, high temperature stability, etc., and is suitable for making matrix or skeleton of light heat-insulating and ablation-resistant heat-insulating material, and it is also a heat-insulating material widely used in inert gas environment above 2000 deg.C.
Although the carbon fiber bonded carbon fiber composite material has excellent ultrahigh temperature properties such as high temperature mechanical properties, high temperature low thermal conductivity and the like, the carbon fiber bonded carbon fiber composite material has a fatal weakness because the carbon fiber bonded carbon fiber composite material is a full carbon material: oxidation started to occur at 400 ℃ under an air atmosphere. This weakness greatly limits its use as a material for high temperature thermal protection systems. At present, in the aspect of preventing oxidation of carbon materials, the surface composite oxidation resistant coating is considered to be the most effective method for improving the oxidation resistance of the carbon-based materials.
SiC-based oxidation resistant coatingThe layer is oxidized at high temperature (1400-1600 ℃) to form a silicate glass layer, external oxygen is inhibited from diffusing to the interior of the material, and the base material is effectively protected, so that good oxidation resistance is presented, (700-1200 ℃) in medium-temperature and ultrahigh-temperature aerobic environments>Effective protection of the carbon material is difficult to achieve at 1600 ℃. The prior art exists of boride (ZrB) by addition of transition metals2、TaB2Or HfB2) The proposal of modifying the SiC coating is that boride is oxidized at medium and low temperature to generate liquid B2O3The composite glass plays a good role in protecting the carbon substrate from oxidation at medium and low temperature, and the oxide of the transition metal can interact with silicate glass at ultrahigh temperature to form an M-Si-O composite glass layer, so that the stability of the glass layer is enhanced. However, the solutions disclosed in the prior art for modifying SiC coatings with transition metal borides require higher sintering temperatures in the preparation.
At present, the method for preparing the coating on the surface of the carbon material mainly comprises a brushing method, an embedding method, an in-situ reaction method, a plasma spraying method and the like. Although the plasma spraying method is easy to control the thickness of the coating and the content of boride in the coating, the required equipment condition is harsh, the cost is high, the porosity of the coating is high, and the bonding strength is poor; the embedding method and the in-situ reaction method have the advantages of low cost, simplicity, easy implementation, uniform distribution of synthetic phases, good compatibility with a substrate, high interface bonding strength and the like, but the content of each component in the coating and the thickness of the coating are difficult to control, and the reaction generally needs high sintering temperature (>2000 ℃). The coating paste is prepared by mixing borosilicate glass, and the preparation temperature of the coating can be reduced by a brushing process, but the use temperature of the coating is reduced due to the presence of a large amount of glass phase. The polymer cracked SiC coating can significantly lower the formation temperature of the coating, but there is greater shrinkage during the cracking process.
Meanwhile, as a thermal protection system used in an ultrahigh-temperature environment, the thermal protection system has higher requirements on the high-temperature thermal conductivity of the carbon fiber bonded carbon fiber composite material, and on one hand, the prepared carbon fiber framework is required to have high porosity and reduce the thermal conductivity; in addition, it is desirable to have a high emissivity coating that can radiate the heat of the substrate quickly and efficiently in an efficient manner to reduce the temperature of the substrate.
Disclosure of Invention
The invention aims to provide a composition for preparing a high-emissivity antioxidant coating on the surface of a porous carbon fiber heat-insulating material, the high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material prepared by the composition, and a preparation method of the high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material.
In order to achieve the purpose, the invention provides the following technical scheme:
1. the invention provides a composition for preparing a high-emissivity antioxidant coating on the surface of a porous carbon fiber heat insulating material, which comprises the following components: transition metal boride, refractory metal silicide, silicon carbide powder, polycarbosilane and cerium oxide.
2. The composition according to claim 1, wherein the composition,
in the composition, the mass percentages of the components are as follows:
Figure BDA0001921239000000031
3. the composition according to claim 1 or 2, wherein the transition metal boride is selected from any one or more of zirconium boride, hafnium boride, tantalum boride; and/or
The refractory metal silicide is selected from any one or more of molybdenum silicide and tantalum silicide.
4. The composition according to claim 1 or 2, wherein the cerium oxide is cerium oxide nanopowder.
5. According to the composition of claim 4, the cerium oxide nanopowder is prepared by a sol-gel method.
6. According to the composition of claim 5, the cerium oxide nanopowder is prepared as follows:
dissolving soluble or soluble cerium salt, adding a catalyst, and stirring to react to generate sol;
and drying, roasting and grinding the sol in sequence to obtain the cerium oxide nano powder.
7. The composition of claim 6, wherein the cerium salt is cerium nitrate and the catalyst is oxalic acid or citric acid; and
the sol-gel reaction conditions are as follows:
the concentration of the solution obtained after dissolving the cerium nitrate is 0.5 to 1 mol/L;
the molar ratio of the cerium nitrate to the catalyst is 1 (1-4);
the sol generating reaction is carried out under the condition of constant temperature water bath at 40-80 ℃;
the drying is carried out at 80 to 140 ℃; and/or
The firing is carried out at 500 to 800 ℃.
8. The second aspect of the invention provides a preparation method of a high-emissivity antioxidant coating on the surface of a porous carbon fiber heat-insulating material, which comprises the following steps:
(1) mixing the composition of any one of technical schemes 1 to 7 with an organic solvent capable of dissolving polycarbosilane to prepare slurry;
(2) coating the slurry onto a porous carbon fiber thermal insulation material;
(3) and (3) drying, heat treating and sintering the porous carbon fiber heat-insulating material treated in the step (2) in sequence to obtain the high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material.
9. According to the preparation method of claim 8, the used amount of the organic solvent satisfies the following condition: the mass percentage of the polycarbosilane in the mixed solution of the organic solvent and the polycarbosilane is 5 to 30 percent.
10. According to the preparation method of the technical scheme 8 or 9, the porous carbon fiber heat-insulating material is a carbon/carbon composite material prepared by a viscose base, phenolic aldehyde group or polyacrylonitrile-based chopped carbon fiber by a filter pressing method or a vacuum filtration method.
11. The preparation method according to claim 8 or 9, further comprising, after the step (2) of coating the slurry on the porous carbon fiber thermal insulation material, the following steps:
drying the porous carbon fiber heat-insulating material at 50-80 ℃ for 10-50 minutes, then spraying and leveling by using a spray gun, and drying at 80-100 ℃ for 3-8 hours after spraying.
12. The production method according to claim 8 or 9, wherein in the step (4), the drying is performed at 60 to 90 ℃, and the drying time is controlled to be 6 to 12 hours;
the heat treatment is carried out at 180 to 250 ℃, and the heat preservation time is controlled to be 6 to 24 hours; and/or
The sintering is carried out in an inert atmosphere, the sintering temperature is 1100-1300 ℃, the heating rate is 1-5 ℃/min, and the heat preservation time is controlled to be 1-3 hours.
13. The third aspect of the invention provides a high-emissivity antioxidant coating on the surface of a porous carbon fiber heat-insulating material, which is prepared by adopting the preparation method of any one of technical schemes 8 to 12; preferably, the high emissivity oxidation resistant coating has a thickness of 100 to 200 microns.
Advantageous effects
The technical scheme of the invention has the following advantages:
in the composition for preparing the high-emissivity anti-oxidation coating on the surface of the porous carbon fiber heat-insulating material, which is provided by the invention, cerium oxide inhibits the attenuation of the high-temperature emissivity of the oxidation coating, the defect of the radiation performance attenuation of the high-emissivity coating in a high-temperature aerobic environment is overcome, and meanwhile, polycarbosilane is used as a high-temperature binder, and a polymer is used for cracking and sintering the coating, so that the sintering temperature is reduced.
The high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material has the advantages of high emissivity, low high-temperature thermal conductivity and high ultrahigh-temperature stability.
The preparation method provided by the invention adopts a heat treatment process combining slurry rinsing and spraying to prepare the coating on the surface of the porous carbon fiber heat-insulating material, no complex equipment is needed, the preparation temperature is low, the cost is low, the period is short, the prepared high-emissivity anti-oxidation coating on the surface of the porous carbon fiber heat-insulating material has good ultrahigh temperature stability, and the preparation method is expected to be applied to a thermal protection system of a hypersonic aircraft.
Drawings
FIG. 1 is a surface SEM photograph (500X) of the product obtained in example 1;
FIG. 2 is a surface SEM photograph (300X) of the product obtained in example 1;
FIG. 3 is a side SEM photograph (100X) of the product of example 1;
FIG. 4 is a side SEM image (200X) of the product made in example 1.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
The invention provides a composition for preparing a high-emissivity antioxidant coating on the surface of a porous carbon fiber heat-insulating material, which comprises the following components: transition metal boride, refractory metal silicide, silicon carbide powder, polycarbosilane and cerium oxide.
In the composition provided by the invention, the refractory metal silicide not only can improve the emissivity of the coating, but also can improve the stability of the coating at high temperature; the cerium oxide is used as an oxide ceramic material with a high melting point (2600 ℃), has stable emissivity at 1000-2000 ℃, is not attenuated, can be used for inhibiting the attenuation of the high-temperature emissivity of the oxidation coating, and overcomes the defect that the radiation performance of the high-emissivity coating is attenuated in a high-temperature aerobic environment; meanwhile, polycarbosilane is used as a high-temperature binder, and the polymer is cracked to sinter the coating, so that the sintering temperature is reduced.
In some preferred embodiments, the mass percentages of the components are as follows:
transition metal boride: 10 to 30%, for example, may be 10%, 15%, 20%, 25% or 30%;
refractory metal silicide: 15 to 45%, for example, 15%, 20%, 25%, 30%, 35%, 40% or 45%;
silicon carbide powder: 15 to 25%, for example, 15%, 20% or 25%;
polycarbosilane: 10 to 20%, for example, may be 10%, 15% or 20%;
cerium oxide: 5 to 10%, for example, 5%, 6%, 7%, 8%, 9% or 10% may be used.
In some preferred embodiments, the transition metal boride is selected from zirconium boride (ZrB)2) Hafnium boride (HfB)2) Tantalum boride (TaB)2) Any one or more of.
In some preferred embodiments, the refractory metal silicide is selected from molybdenum silicide (MoSi)2) Tantalum silicide (TaSi)2) Any one or more of. It should be noted that the term "refractory" means that the melting point is 1650 ℃ or higher.
In some preferred embodiments, the cerium oxide is cerium oxide nanopowder, which can be prepared by a sol-gel method. Specifically, the cerium oxide nano powder may be prepared as follows:
dissolving soluble or soluble cerium salt, adding a catalyst, and stirring to react to generate sol; the cerium salt may be cerium nitrate, the catalyst may be oxalic acid or citric acid, and the sol-gel reaction conditions are preferably as follows: the concentration of the solution obtained after dissolving the cerium nitrate is 0.5 to 1mol/L, and may be, for example, 0.5mol/L, 0.6mol/L, 0.7mol/L, 0.8mol/L, 0.9mol/L, or 1 mol/L; the molar ratio of the cerium nitrate to the catalyst is 1 (1-4), and for example, the molar ratio of the cerium nitrate to the catalyst may be 1: 1. 1: 2. 1: 3 or 1: 4; the sol-forming reaction is carried out in a constant-temperature water bath of 40 to 80 ℃ (for example, 40 ℃, 50 ℃, 60 ℃, 70 ℃ or 80 ℃);
and drying, roasting and grinding the prepared sol in sequence to obtain the cerium oxide nano powder. The drying may be performed at 80 to 140 ℃ (e.g., may be 80 ℃, 90 ℃, 100 ℃, 110 ℃, 120 ℃, 130 ℃ or 140 ℃), and the firing may be performed at 500 to 800 ℃ (e.g., may be 500 ℃, 600 ℃, 700 ℃ or 800 ℃).
The invention refers to the ease of dissolution, soluble describes the size of the dissolving capacity of a substance in a solvent. It has the following relationship with the solubility of the substance (20 ℃, solvent is water):
solubility in water Is easy to dissolve Soluble in water
Solubility (20 ℃ C.) ＞10g 1～10g
The invention also provides a preparation method of the high-emissivity anti-oxidation coating on the surface of the porous carbon fiber heat-insulating material, the method adopts a heat treatment process combining slurry rinsing and spraying to prepare the coating on the surface of the porous carbon fiber heat-insulating material, no complex equipment is needed, the preparation temperature is low, the cost is low, the period is short, and the prepared high-emissivity anti-oxidation coating on the surface of the porous carbon fiber heat-insulating material has good ultrahigh temperature stability and is expected to be applied to a thermal protection system of a hypersonic aircraft.
Specifically, the preparation method comprises the following steps:
(1) preparing slurry for painting
Mixing the composition provided by the invention with an organic solvent capable of dissolving polycarbosilane to prepare slurry; in order to obtain a slurry with a suitable viscosity, the organic solvent is used in an amount satisfying the following conditions: the polycarbosilane in the mixed solution of the organic solvent and the polycarbosilane is 5 to 30 percent by mass, for example, 5 percent, 10 percent, 15 percent, 20 percent, 25 percent or 30 percent.
In the present invention, the kind of the organic solvent is not particularly limited, but xylene or divinylbenzene is preferably used.
In the process of preparing the slurry, Polycarbosilane (PCS) can be ground into powder, then the powder is dissolved in an organic solvent to prepare a PCS solution with the PCS content (mass percentage content) of 5-30%, then other components (transition metal boride, silicon carbide powder and cerium oxide) in the composition are added into the PCS solution, and the mixture is uniformly mixed to obtain the slurry for brushing.
In some embodiments, the mixing process may employ a ball milling process. The PCS solution (containing transition metal boride, silicon carbide powder, polycarbosilane and cerium oxide) is put into a ball milling device, zirconia balls are used as grinding media, and ball milling and stirring are carried out for a period of time (for example, 6 to 24 hours), so as to obtain uniform slurry.
(2) Coating the slurry onto porous carbon fiber thermal insulation material
In this step, the slurry prepared in step (1) may be uniformly applied to the porous carbon fiber heat insulating material using a brush application method. To further ensure the flatness of the coating, after finishing the painting, the porous carbon fiber thermal insulation material may be dried at 50 to 80 ℃ (e.g., 50 ℃, 60 ℃, 70 ℃ or 80 ℃) for 10 to 50 minutes (e.g., 10 minutes, 20 minutes, 30 minutes, 40 minutes or 50 minutes), and then spray-leveled using a spray gun, and after the spraying, the porous carbon fiber thermal insulation material may be dried at 80 to 100 ℃ (e.g., 80 ℃, 90 ℃ or 100 ℃) for 3 to 8 hours (3 hours, 4 hours, 5 hours, 6 hours, 7 hours or 8 hours), thereby forming a preset layer on the surface of the porous carbon fiber thermal insulation material.
In the step, the porous carbon fiber heat-insulating material is preferably a carbon/carbon composite material prepared by a viscose base, phenolic group or polyacrylonitrile-based chopped carbon fiber by a filter pressing method or a vacuum filtration method. The preparation process can adopt the existing preparation method, and the invention is not explained here. Before the slurry is coated on the porous carbon fiber heat-insulating material, the porous carbon fiber heat-insulating material can be cut into materials with the requirement of composite size, then the materials are polished by sand paper with different roughness, and then ultrasonic cleaning and drying are carried out after polishing.
(3) Synthetic coating
And (3) drying, heat treating and sintering the porous carbon fiber heat-insulating material treated in the step (2) in sequence to obtain the high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material.
In some preferred embodiments, the drying is performed at 60 to 90 ℃ (e.g., 60 ℃, 70 ℃, 80 ℃ or 90 ℃), and the drying time is controlled to be 6 to 12 hours (e.g., 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours or 12 hours);
the heat treatment is performed at 180 to 250 ℃ (for example, 180 ℃, 190 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃ or 250 ℃), and the holding time is controlled to be 6 to 24 hours (for example, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours or 24 hours);
the sintering is performed under an inert atmosphere such as argon, the sintering temperature is 1100 to 1300 ℃ (for example, 1100 ℃, 1200 ℃ or 1300 ℃), the heating rate is 1 to 5 ℃/min (for example, 1 ℃/min, 2 ℃/min, 3 ℃/min, 4 ℃/min or 5 ℃/min), and the holding time is controlled to be 1 to 3 hours (for example, 1 hour, 2 hours or 3 hours).
The invention also provides a high-emissivity antioxidant coating on the surface of the porous carbon fiber heat-insulating material.
The coating is prepared by the preparation method provided by the invention, and has the advantages of high emissivity, low high-temperature thermal conductivity and good ultrahigh-temperature stability. Preferably, the high emissivity oxidation resistant coating has a thickness of 100 to 200 microns, for example, 100 microns, 150 microns or 200 microns.
The following are examples of the present invention.
Example 1
(1) Dissolving cerium nitrate in deionized water under magnetic stirring, wherein the concentration of cerium oxide is 0.5 mol/L. Using citric acid as a catalyst, wherein the molar ratio of cerium nitrate to citric acid is 1:2, and stirring in a water bath at 60 ℃ for 3 hours to obtain the gel. And drying the prepared gel at 120 ℃ for 12h, then roasting at 500 ℃ for 2h, and performing ball milling and sieving to obtain the cerium oxide nano powder.
(2) Cutting the porous carbon fiber heat-insulating material into a fiberboard with the thickness of 3.0cm multiplied by 1.0cm, polishing and flattening by SiC sand paper with the sizes of 500 meshes, 1000 meshes, 2000 meshes and 3000 meshes, ultrasonically cleaning for 20min, and drying in an oven at the temperature of 80 ℃ for later use.
(3) Grinding polycarbosilane into powder, dissolving the ground Polycarbosilane (PCS) powder into a xylene solution to prepare a PCS solution, wherein the PCS content in the solution is 10 percent (mass percentage); hafnium boride (HfB)2) Molybdenum silicide (MoSi)2) Silicon carbide (SiC), cerium oxide (CeO)2) Added to a Polycarbosilane (PCS) solution. Wherein hafnium boride (HfB)2) Molybdenum silicide (MoSi)2) Silicon carbide (SiC), Polycarbosilane (PCS) and cerium oxide (CeO)2) The mass percentages of the components are respectively as follows: 20%, 35%, 20%, 15%, 10%. And (3) putting the polycarbosilane solution into a ball milling device for milling, and ball milling and stirring for 6 hours by taking zirconia balls as a milling medium to form uniform slurry with proper viscosity.
(4) And (3) coating the prepared slurry on the porous carbon fiber heat-insulating material treated in the step (2) by using a brush, drying for 30 minutes at 60 ℃ after coating, then spraying and leveling by using a spray gun under the pressure of 0.25MPa, drying for 4 hours at 80 ℃ in an oven after spraying, and forming a preset layer on the surface of the porous carbon fiber heat-insulating material.
(5) And (3) drying the material treated in the step (4) in an oven at 90 ℃ for 6 hours to remove the organic solvent, crosslinking at 240 ℃ for 12 hours, heating to 1200 ℃ under the protection of argon at the heating rate of 5 ℃/min, cracking and sintering for 2 hours, and then cooling along with the furnace to obtain the high-emissivity antioxidant coating, wherein the appearance graphs of the coating are shown in fig. 1, fig. 2, fig. 3 and fig. 4.
Example 2
(1) Dissolving cerium nitrate in deionized water by magnetic stirring, wherein the concentration of cerium oxide is 1 mol/L. Using citric acid as a catalyst, wherein the molar ratio of cerium nitrate to citric acid is 1:2, and stirring in a water bath at 60 ℃ for 4 hours to obtain the gel. And drying the prepared gel at 120 ℃ for 12h, then roasting at 500 ℃ for 2h, and performing ball milling and sieving to obtain the cerium oxide nano powder.
(2) Cutting the porous carbon fiber heat-insulating material into a fiberboard with the thickness of 3.0cm multiplied by 1.0cm, polishing and flattening by SiC sand paper with the sizes of 500 meshes, 1000 meshes, 2000 meshes and 3000 meshes, ultrasonically cleaning for 20min, and drying in an oven at the temperature of 80 ℃ for later use.
(3) Grinding polycarbosilane into powder, dissolving the ground Polycarbosilane (PCS) powder into a xylene solution to prepare a PCS solution, wherein the PCS content in the solution is 10 percent (mass percentage); hafnium boride (HfB)2) Molybdenum silicide (MoSi)2) Silicon carbide (SiC), cerium oxide (CeO)2) Added to a Polycarbosilane (PCS) solution. Wherein hafnium boride (HfB)2) Molybdenum silicide (MoSi)2) Silicon carbide (SiC), Polycarbosilane (PCS) and cerium oxide (CeO)2) The mass percentage of the components is respectively 25%, 30%, 20%, 15% and 10%. And (3) putting the polycarbosilane solution into a ball milling device for milling, and ball milling and stirring for 6 hours by taking zirconia balls as a milling medium to form uniform slurry with proper viscosity.
(4) And (3) coating the prepared slurry on the porous carbon fiber heat-insulating material treated in the step (2) by using a brush, drying for 30 minutes at 60 ℃ after coating, then spraying and leveling by using a spray gun under the pressure of 0.25MPa, drying for 4 hours at 80 ℃ in an oven after spraying, and forming a preset layer on the surface of the porous carbon fiber heat-insulating material.
(5) And (3) drying the material treated in the step (4) in an oven at 90 ℃ for 6 hours to remove the organic solvent, crosslinking at 240 ℃ for 12 hours, heating to 1300 ℃ under the protection of argon, cracking and sintering at the heating rate of 5 ℃/min for 2 hours, and then cooling along with a furnace to obtain the high-emissivity oxidation-resistant coating.
Example 3
The procedure is essentially the same as in example 1, except that:
in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000111
example 4
The procedure is essentially the same as in example 1, except that:
in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000112
example 5
The procedure is essentially the same as in example 1, except that:
in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000113
Figure BDA0001921239000000121
example 6
The procedure is essentially the same as in example 1, except that: in step (3), no cerium oxide is added.
Example 7
The procedure is essentially the same as in example 1, except that: in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000122
example 8
The procedure is essentially the same as in example 1, except that: in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000123
example 9
The procedure is essentially the same as in example 1, except that: in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000124
example 10
The procedure is essentially the same as in example 1, except that:
in the step (3), the mass percentage of each component is as follows:
Figure BDA0001921239000000131
emissivity sensing
The emissivity, also called radiance, is the ratio of the radiation exitance of the black body between the actual object and the black body under a certain temperature condition and other conditions are the same, and the calculation method is shown in the following formula:
Figure BDA0001921239000000132
in the formula, Mh(T) and M (T) respectively mean the radiation emittance of the black body and the actual object under the condition of the temperature T under the same other conditions.
The emissivity is in a range of more than 0 and less than 1, and the emissivity means the radiation capability of an actual object is close to that of a black body. The closer the emissivity is to 1, the stronger its radiation power is. High emissivity materials are desirable products.
The results are shown in Table 1.
TABLE 1
Figure BDA0001921239000000133
Figure BDA0001921239000000141
From the above test results, it can be seen that the emissivity of the coating layers prepared in examples 1 to 5 can reach 0.85 or more. In examples 6 to 10, usable coatings could not be obtained, and some coatings could have a certain emissivity, but the effect was inferior to that of examples 1 to 5.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims (11)

1. A composition for preparing a high emissivity, oxidation resistant coating on the surface of a porous carbon fiber thermal insulation material, said composition comprising the following components: transition metal boride, refractory metal silicide, silicon carbide powder, polycarbosilane and cerium oxide; the transition metal boride is selected from any one or more of zirconium boride, hafnium boride and tantalum boride; the refractory metal silicide is selected from any one or more of molybdenum silicide and tantalum silicide;
in the composition, the mass percentages of the components are as follows:
Figure FDA0002409848490000011
2. the composition as claimed in claim 1, wherein the cerium oxide is cerium oxide nanopowder.
3. The composition of claim 2, wherein the cerium oxide nanopowder is prepared using a sol-gel process.
4. The composition as claimed in claim 3, wherein the cerium oxide nano-powder is prepared by the following method:
dissolving soluble or soluble cerium salt, adding a catalyst, and stirring to react to generate sol;
and drying, roasting and grinding the sol in sequence to obtain the cerium oxide nano powder.
5. The composition of claim 4, wherein the cerium salt is cerium nitrate and the catalyst is oxalic acid or citric acid; and
the sol-gel reaction conditions are as follows:
the concentration of the solution obtained after dissolving the cerium nitrate is 0.5 to 1 mol/L;
the molar ratio of the cerium nitrate to the catalyst is 1 (1-4);
the sol generating reaction is carried out under the condition of constant temperature water bath at 40-80 ℃;
the drying is carried out at 80 to 140 ℃; and/or
The firing is carried out at 500 to 800 ℃.
6. A preparation method of a high-emissivity antioxidant coating on the surface of a porous carbon fiber heat-insulating material is characterized by comprising the following steps:
(1) mixing the composition of any one of claims 1 to 5 with an organic solvent capable of dissolving polycarbosilane to prepare a slurry;
(2) coating the slurry onto a porous carbon fiber thermal insulation material;
(3) drying, heat treating and sintering the porous carbon fiber heat insulating material coated with the slurry in sequence to obtain a high-emissivity antioxidant coating on the surface of the porous carbon fiber heat insulating material; in the step (3), the drying is carried out at 60 to 90 ℃ for 6 to 12 hours; the heat treatment is carried out at 180 to 250 ℃, and the heat preservation time is controlled to be 6 to 24 hours; the sintering is carried out in an inert atmosphere, the sintering temperature is 1100-1300 ℃, the heating rate is 1-5 ℃/min, and the heat preservation time is controlled to be 1-3 hours.
7. The preparation method according to claim 6, wherein the porous carbon fiber heat-insulating material is a carbon/carbon composite material prepared from viscose-based, phenolic-based or polyacrylonitrile-based chopped carbon fibers by a filter pressing method or a vacuum filtration method.
8. The manufacturing method according to claim 6, wherein, after the slurry is coated on the porous carbon fiber thermal insulation material in the step (2), the following process is further included:
drying the porous carbon fiber heat-insulating material at 50-80 ℃ for 10-50 minutes, then spraying and leveling by using a spray gun, and drying at 80-100 ℃ for 3-8 hours after spraying.
9. The production method according to claim 6, wherein the organic solvent is used in an amount satisfying the following condition: the mass percentage of the polycarbosilane in the mixed solution of the organic solvent and the polycarbosilane is 5 to 30 percent.
10. A high-emissivity antioxidant coating on the surface of a porous carbon fiber heat-insulating material, which is characterized by being prepared by the preparation method of any one of claims 6 to 9.
11. The high emissivity oxidation resistant coating of claim 10, wherein the high emissivity oxidation resistant coating has a thickness of 100 to 200 microns.
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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5834070A (en) * 1996-04-04 1998-11-10 International Center For Electron Beam Technologies Of E.O. Paton Electric Welding Institute Method of producing protective coatings with chemical composition and structure gradient across the thickness

Family Cites Families (8)

* Cited by examiner, † Cited by third party
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CN104446656B (en) * 2014-12-15 2016-10-05 航天特种材料及工艺技术研究所 A kind of preparation method of porous carbon materials ORC
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CN107700205A (en) * 2017-08-02 2018-02-16 六安成邦新材料有限公司 A kind of preparation method of carbon fiber surface antioxidant coating
CN107935634B (en) * 2017-11-07 2020-08-14 航天材料及工艺研究所 Refractory metal compound high-temperature oxidation-resistant coating and preparation method thereof
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Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5834070A (en) * 1996-04-04 1998-11-10 International Center For Electron Beam Technologies Of E.O. Paton Electric Welding Institute Method of producing protective coatings with chemical composition and structure gradient across the thickness

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