Carbon-ceramic synergic skeleton modified c / c composite material and preparation method thereof

Abstract

The application discloses a kind of carbon-tao collaborative skeleton modified C / C composite material and preparation method thereof, belong to ceramic modified C / C composite material technical field.The method disclosed in the application comprises the following steps: low-density C / C composite material is immersed in initial emulsion, then sequentially heat curing, drying, carbonization and deposition pyrolytic carbon treatment, obtain porous carbon matrix;ZrC suspension liquid is introduced into porous carbon matrix by suction filtration treatment, obtain carbon matrix containing carbon-tao collaborative skeleton;Carbon matrix containing carbon-tao collaborative skeleton is immersed in organic zirconium polymer solution, vacuum impregnation-drying and heat treatment are carried out several times, and carbon-tao collaborative skeleton modified C / C composite material is obtained;The method can realize the adjustment of carbon and ceramic interface reaction by adjusting the filtration parameters, and solves the technical problem of poor interface compatibility between carbon matrix and ceramic particles in the ceramic modification process.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of ceramic modified C / C composite materials, and particularly relates to a carbon-ceramic collaborative skeleton modified C / C composite material and a preparation method thereof. BACKGROUND

[0002] Carbon / carbon (C / C) composite material has excellent characteristics such as high specific strength / specific modulus, high high-temperature strength retention rate, low thermal expansion coefficient, and is an ideal super-high-temperature structural material, and plays an important role in the development of new aerospace vehicles. However, the C / C composite material will be oxidized and damaged in an oxygen-containing environment above 450 DEG C, which will cause the performance of the C / C composite material to decrease greatly, and seriously restricts the application of the C / C composite material in a high-temperature oxygen-containing environment. Studies have shown that introducing carbide, boride and other ultra-high-temperature ceramics (UHTC) is an effective way to improve the anti-oxidation and ablation performance of the C / C composite material. Common ultra-high-temperature ceramic matrix modification methods include chemical vapor infiltration (CVI), slurry impregnation (SI), reactive melt infiltration (RMI) and precursor impregnation-pyrolysis (PIP) and the like, and a combination process thereof. Compared with other C / C-UHTC composite material preparation processes, PIP has low preparation temperature, good material structure designability, can realize near-net-size forming of large and complex-shaped components, and can obtain a high-purity ceramic matrix.

[0003] Studies have shown that regulating and modifying the pore structure of the preform is beneficial to realizing the controllable and uniform distribution of the ceramic phase in the composite material, and is of great significance to improving the performance of the material. However, ZrC ceramic can theoretically completely fill the porous C / C composite material, but in the precursor impregnation-pyrolysis process, the ceramic conversion rate of the precursor solution is only 40-50%; at the same time, in the process of high-temperature pyrolysis and ceramicization, gas inevitably escapes and volume shrinkage occurs, and there are many micropores in the obtained ceramic matrix, and after introducing the ceramic phase into the carbon matrix, a large number of interfaces are formed between the ceramic phase and the porous carbon matrix. Due to the intrinsic brittleness of the ceramic and the inevitable interfacial reaction with the carbon matrix, residual thermal stress exceeding the strength of the matrix will be introduced into the matrix, and the mechanical performance will be generally reduced, which will lead to the decrease of the comprehensive performance of the composite material, and greatly limits the application of the composite material. SUMMARY

[0004] The purpose of the present application is to provide a carbon-ceramic collaborative skeleton modified C / C composite material and a preparation method thereof, so as to solve the technical problem of poor interface compatibility between the carbon matrix and the ceramic particles in the existing ceramic modification process.

[0005] In order to achieve the above purpose, the following technical solutions are adopted in the present application:

[0006] The application discloses a preparation method of carbon-toughened ceramic synergic skeleton modified C / C composite material.

[0007] The low-density C / C composite material is immersed in an initial emulsion, and then sequentially subjected to heat curing, drying, carbonization and deposition pyrolysis carbon treatment, so that a porous carbon matrix is obtained.

[0008] The ZrC suspension is introduced into the porous carbon matrix through suction filtration treatment, so that a carbon matrix containing a carbon-toughened ceramic synergic skeleton is obtained.

[0009] The carbon matrix containing the carbon-toughened ceramic synergic skeleton is immersed in an organic zirconium polymer solution, and vacuum impregnation-drying and heat treatment are performed for several times, so that the carbon-toughened ceramic synergic skeleton modified C / C composite material is obtained.

[0010] Further, the curing treatment is performed in an oven; the temperature of the curing treatment is 70-90 DEG C, and the time is 24-36 h; the drying is performed at normal pressure and at 80-120 DEG C for 5-10 h.

[0011] Further, the carbonization parameters are as follows: under an argon atmosphere, the temperature is raised to 750-1000 DEG C at a rate of 2-10 DEG C / min, and the temperature is kept for 2-4 h;

[0012] The deposition pyrolysis carbon treatment parameters are as follows: the heating equipment is heated to 900-1100 DEG C at a rate of 1-5 DEG C / min under the protection of argon, then CH4 is introduced for deposition for 40-300 min, and the porous carbon matrix is obtained after cooling to room temperature; during the heating process and the cooling process, the argon flow rate is 1-3 L / min; during the CH4 introduction and deposition, the argon flow rate is 2-5 L / min.

[0013] Further, the ZrC suspension is obtained by mixing ZrC powder and anhydrous ethanol; the particle size of the ZrC powder is 100 nm-2 mu m; and the mass ratio of the ZrC powder to the anhydrous ethanol is (5-15) g:(15-35) g.

[0014] Further, the step of introducing the ZrC suspension into the porous carbon matrix through suction filtration treatment is as follows:

[0015] The ZrC suspension is introduced into the porous carbon matrix by using a suction filtration device, ZrC suspension on the upper surface of the porous carbon matrix is sucked dry, then the ZrC suspension is continuously added, and the cycle is repeated for several times, until the ZrC suspension on the upper surface of the porous carbon matrix cannot be absorbed, and the carbon matrix containing the carbon-toughened ceramic synergic skeleton is obtained after drying.

[0016] Further, during the process of obtaining the carbon matrix containing the carbon-toughened ceramic synergic skeleton, the drying temperature is 70-100 DEG C, and the time is 8-10 h.

[0017] The number of cycles is 3-5.

[0018] Further, the organic zirconium polymer solution is obtained by stirring and mixing the organic zirconium polymer and xylene;

[0019] The stirring mode is magnetic stirring, and the magnetic stirring time is 1-4 h.

[0020] The dosage ratio of the organic zirconium polymer and xylene is (60-70) g:(30-40) g.

[0021] Further, the number of cycles of vacuum impregnation-drying and heat treatment is 2-9.

[0022] Further, the heat treatment parameters are as follows: in an argon atmosphere, the temperature is raised to 1500-1600 DEG C at a temperature raising rate of 5-10 DEG C / min, and the heating time is 2-3 h.

[0023] The application also discloses a carbon-tao collaborative skeleton modified C / C composite material prepared by the preparation method.

[0024] Compared with the prior art, the application has the following beneficial effects:

[0025] The application discloses a preparation method of a carbon-tao collaborative skeleton modified C / C composite material.

[0026] Further, by introducing the ZrC ceramic powder into the porous carbon matrix, the content of the introduced ZrC ceramic powder can be controlled according to the particle size of the ZrC ceramic powder and the change of the number of times of suction filtration, and then the 3D reaction interface is constructed, which can help to reduce the nucleation work, increase the driving force required for nucleation, promote crystal nucleation, be beneficial to the formation of a new phase of ceramic, effectively improve the ceramic conversion rate, and thus improve the internal ceramic density of the material prepared by the traditional matrix modification technology.

[0027] Further, the particle size and surface morphology of the introduced ZrC ceramic powder significantly affect the interface adsorption; smaller particle size increases the interface specific surface area, and improves the surface energy, so that the interaction is more likely to occur; in addition, the nano ceramic particles with rough and porous surface have higher specific surface area and more active sites, so that the adsorption is more likely to occur; the combination of physical adsorption at the interface and chemical bond effect greatly improves the adsorption capacity, and significantly enhances the tightness of the introduction of ZrC ceramic and the carbon matrix during the vacuum impregnation-drying and heat treatment process of the organic zirconium polymer solution, thereby improving the overall density and comprehensive performance of the composite material.

[0028] The application also discloses a carbon-tao synergic skeleton modified C / C composite material prepared by the method, which has a high compatibility reaction interface, improved ceramic conversion rate, and stronger combination of the carbon matrix and the ceramic matrix by introducing ceramic powder with a suitable particle size to the pores of the porous matrix to construct a carbon-tao synergic 3D structure, so that the transmission efficiency of stress between the fiber-matrix is improved, and the stress concentration in the material is relieved; in addition, the composite material with the carbon-tao synergic structure interface has better oxidation and ablation resistance, so that the strengthening of the interface is the key to optimizing the overall performance of the ceramic modified C / C composite material. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 A preparation flow chart of the carbon-tao synergic skeleton modified C / C composite material of the application;

[0030] Figure 2 A morphology diagram of the porous carbon matrix prepared in Example 1;

[0031] Wherein: a-50 μm; b-10 μm;

[0032] Figure 3 An SEM diagram of the carbon matrix containing the carbon-tao synergic skeleton prepared in Example 1;

[0033] Figure 4 An X-ray diffraction diagram of the carbon-tao synergic skeleton modified C / C composite material prepared in Example 1;

[0034] Figure 5 An SEM diagram of the cross sections of different composite materials;

[0035] Wherein: a-conventional ZrC ceramic modified C / C composite material; b-carbon-tao synergic skeleton modified C / C composite material. DETAILED DESCRIPTION

[0036] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0037] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0038] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0039] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”

[0040] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0041] like Figure 1 As shown, this invention provides a method for preparing carbon-ceramic synergistic skeleton modified C / C composite materials, comprising the following steps:

[0042] The low-density C / C composite material was immersed in the initial emulsion, and then subjected to heating curing, drying, carbonization and deposition of pyrolytic carbon in sequence to obtain a porous carbon matrix.

[0043] The ZrC suspension was introduced into a porous carbon matrix by vacuum filtration to obtain a carbon matrix containing a carbon-ceramic synergistic framework.

[0044] A carbon matrix containing a carbon-ceramic synergistic framework was impregnated in an organozirconium polymer solution, and subjected to several vacuum impregnation-drying and heat treatment processes to obtain a carbon-ceramic synergistic framework modified C / C composite material.

[0045] Preferably, the initial emulsion is prepared by:

[0046] Resorcinol and formaldehyde solution were dissolved in anhydrous ethanol, and hexadecyltrimethylammonium bromide was added. After stirring, the initial emulsion was obtained.

[0047] Further, the ratio of resorcinol, formaldehyde solution, anhydrous ethanol, and hexadecyltrimethylammonium bromide is (12.0~15.0) g : (12.6~18) g : (16.6~20.6) mL : (0.024~0.24) g;

[0048] The stirring method is magnetic stirring; the magnetic stirring time is 10-20 minutes.

[0049] The formaldehyde solution has a mass concentration of 37.5 wt.%.

[0050] Preferably, the heat curing process is as follows: the C / C composite material impregnated with the initial emulsion is placed in an oven at 70~90 ℃ and heated for 24~36 h.

[0051] Preferably, the drying is carried out at normal pressure and 100~120 ℃ for 8~10 h.

[0052] Preferably, the carbonization process parameters are as follows: under an argon atmosphere, the temperature is increased to 750-1000 ℃ at a rate of 2-10 ℃ / min, and held for 2-4 h.

[0053] Preferably, the specific process of depositing pyrolytic carbon treatment is as follows:

[0054] The C / C composite material with a porous framework was placed in a vertical CVD furnace. Argon was used as the protective gas, and the heating equipment was heated to 900-1100 ℃ at a heating rate of 3-5 ℃ / min. Then CH4 was introduced to deposit pyrolytic carbon (PyC) for 40-300 min. After cooling to room temperature, a porous carbon matrix was obtained.

[0055] During the heating and cooling processes, the argon flow rate is 1-3 L / min; during PyC deposition, the argon flow rate is 2-5 L / min.

[0056] Preferably, the specific process of the filtration treatment is as follows: ZrC powder is added to anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension is introduced into a porous carbon matrix using a filtration device. After the suspension on the upper surface of the porous carbon matrix is ​​dried, the suspension is added dropwise. This process is repeated several times until the suspension on the upper surface can no longer be absorbed. After drying, a carbon matrix containing a carbon-ceramic synergistic framework is obtained.

[0057] Among them, the ZrC powder has a particle size of 100nm~2μm and a mass of 5~15g; the anhydrous ethanol has a mass of 15~35g; the drying method is 70~100℃ for 8~10h;

[0058] The cycle number is 3 to 5 times; the drying temperature is 70 to 100℃.

[0059] Preferably, the organozirconium polymer solution is obtained by mixing organozirconium polymer and xylene and then magnetically stirring for 2-4 hours; the ratio of organozirconium polymer to xylene is (60-70) g: (30-40) g.

[0060] The vacuum impregnation-drying process is repeated 2 to 3 times.

[0061] The process parameters for the heat treatment are as follows: in an argon atmosphere, the temperature is increased to 1500-1600 ℃ at a heating rate of 5-10 ℃ / min, and heated for 2-3 h;

[0062] The vacuum impregnation-drying-heat treatment cycle is repeated 7 to 9 times.

[0063] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0064] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.

[0065] Example 1

[0066] A method for preparing a carbon-ceramic synergistic framework modified C / C composite material includes the following steps:

[0067] Step 1: Dissolve 12.0 g of resorcinol and 12.6 g of 37.5 wt.% formaldehyde solution in 16.6 mL of anhydrous ethanol to obtain a mixture; then add 0.024 g of hexadecyltrimethylammonium bromide (CTAB) to the mixture, and magnetically stir the suspension for 10 min to obtain a transparent initial emulsion.

[0068] Step 2: Immerse the low-density C / C in the initial emulsion obtained in Step 1 to completely submerge the block, then place it in a vacuum drying oven and evacuate it until the pressure inside the oven is below 0.09 MPa, maintain this for 30 min, then heat to cure, dry at normal pressure and carbonize, then place it in a CVI furnace, use argon as a protective gas and heat the equipment to 900 ℃ at a heating rate of 3 ℃ / min, then introduce CH4 to deposit PyC for 40 min.

[0069] The heating curing, atmospheric pressure drying and carbonization process is as follows: the low-density C / C composite material is cured in an oven at 70℃ for 24 hours, and then dried at 80℃ under atmospheric pressure for 5 hours; then it is placed in a tube furnace and heated to 750℃ at 2℃ / min, and held for 2 hours. Argon gas is introduced throughout the process as a protective gas to decompose the resin gel in the composite material into carbon.

[0070] The deposition pyrolysis carbon process is as follows: the argon flow rate is set to 1 L / min during the heating and cooling process, 2 L / min during the deposition process, and the CH4 flow rate is 70 L / min; then the temperature is cooled to room temperature to obtain a porous carbon matrix.

[0071] Step 3, Preparation of the carbon-ceramic synergistic framework matrix:

[0072] 5g of ZrC powder with a particle size of 100nm was added to 15g of anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension was introduced into a porous carbon matrix using a vacuum filtration device. After the suspension on the upper surface of the porous carbon matrix was dried, the suspension was added dropwise. The cycle was repeated 3 times until the suspension on the upper surface could no longer be absorbed. The matrix was then dried in a 70℃ oven for 8 hours to obtain a matrix containing a carbon-ceramic synergistic framework.

[0073] Step 4, Precursor Impregnation-Pyrolysis (PIP):

[0074] 60g of organozzirconium polymer (PZC) was added to 30g of xylene and magnetically stirred for 1.5 h to obtain a uniform PZC solution (precursor solution). Then, the carbon-ceramic synergistic framework matrix obtained in step 3 was immersed in the precursor solution so that the bulk was completely immersed. Vacuum impregnation-drying was performed and repeated twice. The dried composite material was placed in a high-temperature furnace for heat treatment. After 7 repeated impregnation-pyrolysis and heat treatment, carbon-ceramic synergistic framework modified C / C composite material was obtained.

[0075] The heat treatment process for preparing C / C-ZrC composite material using the PIP method is as follows: the dried composite material is placed in a high-temperature furnace, argon is introduced as a protective gas, and the equipment is heated to 1600 ℃ for 2 h at a heating rate of 5℃ / min, so that the introduced precursor is decomposed and converted into ZrC ceramic.

[0076] Example 2

[0077] A method for preparing a carbon-ceramic synergistic framework modified C / C composite material includes the following steps:

[0078] Step 1: Dissolve 13.0 g of resorcinol and 15.6 g of 37.5 wt.% formaldehyde solution in 18.6 mL of anhydrous ethanol to obtain a mixture; then add 0.036 g of cetyltrimethylammonium bromide (CTAB) to the mixture and magnetically stir the suspension for 15 min to obtain a transparent initial emulsion.

[0079] Step 2: Immerse the low-density C / C in the initial emulsion obtained in Step 1 to completely submerge the block, then place it in a vacuum drying oven and evacuate it until the pressure inside the oven is below 0.09 MPa, maintain this for 40 min, then heat to cure, dry at normal pressure and carbonize, then place it in a CVI furnace, use argon as a protective gas and heat the equipment to 950 ℃ at a heating rate of 3 ℃ / min, then introduce CH4 to deposit PyC for 80 min.

[0080] The curing, drying and carbonization process is as follows: the low-density C / C composite material is cured in an oven at 80℃ for 24 h, and then dried at 90℃ and normal pressure for 5 h; then it is placed in a tube furnace and heated to 1000℃ at 3℃ / min and held for 2 h, with argon gas introduced as a protective gas throughout the process to decompose the resin gel in the composite material into carbon.

[0081] The carbon deposition pyrolysis process is as follows: the argon flow rate is set to 3 L / min during the heating and cooling process, 5 L / min during the deposition process, and the CH4 flow rate is 90 L / min; carbon deposition pyrolysis is carried out for 300 min; then the temperature is cooled to room temperature to obtain a porous carbon matrix.

[0082] Step 3, Preparation of the carbon-ceramic synergistic framework matrix:

[0083] 10g of ZrC powder with a particle size of 200nm was added to 25g of anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension was introduced into a porous carbon matrix using a vacuum filtration device. After the suspension on the upper surface of the porous carbon matrix was dried, the suspension was added dropwise. The cycle was repeated 5 times until the suspension on the upper surface could no longer be absorbed. The matrix was then dried in a 70℃ oven for 9h to obtain a matrix containing a carbon-ceramic synergistic framework.

[0084] Step 4, Precursor Impregnation-Pyrolysis (PIP):

[0085] 66g of organozzirconium polymer (PZC) was added to 33g of xylene and magnetically stirred for 2h to obtain a uniform PZC solution (precursor solution). Then, the carbon-ceramic synergistic framework matrix obtained in step 3 was immersed in the precursor solution so that the bulk was completely immersed. Vacuum impregnation-drying was performed and repeated twice. The dried composite material was placed in a high-temperature furnace for heat treatment. After 8 repeated impregnation-pyrolysis and heat treatment, carbon-ceramic synergistic framework modified C / C composite material was obtained.

[0086] The heat treatment process for preparing C / C-ZrC composite material using the PIP method is as follows: the dried composite material is placed in a high-temperature furnace, argon is introduced as a protective gas, and the equipment is heated to 1550 ℃ for 2 h at a heating rate of 5℃ / min, so that the introduced precursor is decomposed and converted into ZrC ceramic.

[0087] Example 3

[0088] A method for preparing a carbon-ceramic synergistic framework modified C / C composite material includes the following steps:

[0089] Step 1: Dissolve 14.0 g of resorcinol and 16.6 g of 37.5 wt.% formaldehyde solution in 20.6 mL of anhydrous ethanol to obtain a mixture; then add 0.16 g of hexadecyltrimethylammonium bromide (CTAB) to the mixture and magnetically stir the suspension for 20 min to obtain a transparent initial emulsion.

[0090] Step 2: Immerse the low-density C / C in the initial emulsion obtained in Step 1 to completely submerge the block, then place it in a vacuum drying oven and evacuate it until the pressure inside the oven is below 0.09 MPa, maintain this pressure for 35 minutes, then heat to cure, dry at normal pressure and carbonize it, then place it in a CVI furnace, use argon as a protective gas and heat the equipment to 1000 °C at a heating rate of 4 °C / min, then introduce CH4 to deposit PyC for 60 minutes.

[0091] The curing, drying and carbonization process is as follows: the low-density C / C composite material is cured in an oven at 70℃ for 24 hours, and then dried at 80℃ under normal pressure for 5 hours; then it is placed in a tube furnace and heated to 900℃ at 2℃ / min, and held for 2 hours. Argon gas is introduced throughout the process as a protective gas to decompose the resin gel in the composite material into carbon.

[0092] The deposition pyrolysis carbon process is as follows: the argon flow rate is set to 2 L / min during the heating and cooling process, 4 L / min during the deposition process, and the CH4 flow rate is 80 L / min; then the temperature is cooled to room temperature to obtain a porous carbon matrix.

[0093] Step 3, Preparation of the carbon-ceramic synergistic framework matrix:

[0094] 10g of ZrC powder with a particle size of 1.5μm was added to 30g of anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension was introduced into a porous carbon matrix using a vacuum filtration device. After the suspension on the upper surface of the porous carbon matrix was dried, the suspension was added dropwise. The cycle was repeated 4 times until the suspension on the upper surface could no longer be absorbed. The matrix was then dried in an oven at 70℃ for 9h to obtain a matrix containing a carbon-ceramic synergistic framework.

[0095] Step 4, Precursor Impregnation-Pyrolysis (PIP):

[0096] 70g of organozzirconium polymer (PZC) was added to 40g of xylene and magnetically stirred for 2 h to obtain a uniform PZC solution (precursor solution). Then, the carbon-ceramic synergistic framework matrix obtained in step 3 was immersed in the precursor solution so that the bulk was completely immersed. Vacuum impregnation-drying was performed and repeated 3 times. The dried composite material was placed in a high-temperature furnace for heat treatment. After 8 repeated impregnation-pyrolysis and heat treatment, carbon-ceramic synergistic framework modified C / C composite material was obtained.

[0097] The heat treatment process for preparing C / C-ZrC composite material using the PIP method is as follows: the dried composite material is placed in a high-temperature furnace, argon is introduced as a protective gas, and the equipment is heated to 1500 ℃ for 2 h at a heating rate of 5 ℃ / min, so that the introduced precursor is decomposed and converted into ZrC ceramic.

[0098] Example 4

[0099] A method for preparing a carbon-ceramic synergistic framework modified C / C composite material includes the following steps:

[0100] Step 1: Dissolve 15.0 g of resorcinol and 14.6 g of 37.5 wt.% formaldehyde solution in 20.6 mL of anhydrous ethanol to obtain a mixture; then add 0.08 g of hexadecyltrimethylammonium bromide (CTAB) to the mixture, and magnetically stir the suspension for 20 min to obtain a transparent initial emulsion.

[0101] Step 2: Immerse the low-density C / C in the initial emulsion obtained in Step 1 to completely submerge the block, then place it in a vacuum drying oven and evacuate it until the pressure inside the oven is below 0.09 MPa, maintain this pressure for 30 minutes, then cure it by water bath heating, dry it at normal pressure and carbonize it, and then place it in a CVI furnace. Using argon as a protective gas, heat the equipment to 900 ℃ at a heating rate of 3 ℃ / min, then introduce CH4 to deposit PyC for 100 minutes.

[0102] The curing, drying and carbonization process is as follows: the low-density C / C composite material is cured in an oven at 70 ℃ for 24 h, and then dried at 80 ℃ under normal pressure for 5 h; then it is placed in a tube furnace and heated to 900 ℃ at 2 ℃ / min, and held for 2 h, with argon gas introduced as a protective gas throughout the process, so that the resin gel in the composite material is decomposed into carbon.

[0103] The deposition pyrolysis carbon process is as follows: the argon flow rate is set to 1 L / min during the heating and cooling process, 2 L / min during the deposition process, and the CH4 flow rate is 70 L / min; then the temperature is cooled to room temperature to obtain a porous carbon matrix.

[0104] Step 3, Preparation of the carbon-ceramic synergistic framework matrix:

[0105] 12g of ZrC powder with a particle size of 2μm was added to 18g of anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension was introduced into a porous carbon matrix using a vacuum filtration device. After the suspension on the upper surface of the porous carbon matrix was dried, the suspension was added dropwise. The cycle was repeated 5 times until the suspension on the upper surface could no longer be absorbed. The matrix was then dried in a 70℃ oven for 8 hours to obtain a matrix containing a carbon-ceramic synergistic framework.

[0106] Step 4, Precursor Impregnation-Pyrolysis (PIP):

[0107] 65g of organozzirconium polymer (PZC) was added to 35g of xylene and magnetically stirred for 1.5 h to obtain a uniform PZC solution (precursor solution). Then, the carbon-ceramic synergistic framework matrix obtained in step 3 was immersed in the precursor solution so that the bulk was completely immersed. Vacuum impregnation-drying was performed and repeated 3 times. The dried composite material was placed in a high-temperature furnace for heat treatment. After 7 repeated impregnation-pyrolysis and heat treatment, carbon-ceramic synergistic framework modified C / C composite material was obtained.

[0108] The heat treatment process for preparing C / C-ZrC composite material using the PIP method is as follows: the dried composite material is placed in a high-temperature furnace, argon is introduced as a protective gas, and the equipment is heated to 1600 ℃ for 2 h at a heating rate of 5℃ / min, so that the introduced precursor is decomposed and converted into ZrC ceramic.

[0109] Example 5

[0110] A method for preparing a carbon-ceramic synergistic framework modified C / C composite material includes the following steps:

[0111] Step 1: Dissolve 12.0 g of resorcinol and 16 g of 37.5 wt.% formaldehyde solution in 19.6 mL of anhydrous ethanol to obtain a mixture; then add 0.24 g of cetyltrimethylammonium bromide (CTAB) to the mixture and magnetically stir the suspension for 20 min to obtain a transparent initial emulsion.

[0112] Step 2: Immerse the low-density C / C in the initial emulsion obtained in Step 1 to completely submerge the block, then place it in a vacuum drying oven and evacuate it until the pressure inside the oven is below 0.09 MPa, maintain this pressure for 30 min, then cure it by water bath heating, dry it at normal pressure and carbonize it, then place it in a CVI furnace, use argon as a protective gas, and heat the equipment to 1100 ℃ at a heating rate of 3 ℃ / min, then introduce CH4 to deposit PyC for 250 min.

[0113] The curing, drying and carbonization process is as follows: the low-density C / C composite material is cured in an oven at 70 ℃ for 24 h, and then dried at 80 ℃ under normal pressure for 5 h; then it is placed in a tube furnace and heated to 900 ℃ at 2 ℃ / min, and held for 2 h, with argon gas introduced as a protective gas throughout the process, so that the resin gel in the composite material is decomposed into carbon.

[0114] The deposition pyrolysis carbon process is as follows: the argon flow rate is set to 2 L / min during the heating and cooling process, 4 L / min during the deposition process, and the CH4 flow rate is 70 L / min; then the temperature is cooled to room temperature to obtain a porous carbon matrix.

[0115] Step 3, Preparation of the carbon-ceramic synergistic framework matrix:

[0116] 14 g of ZrC powder with a particle size of 1.5 μm was added to 28 g of anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension was introduced into a porous carbon matrix using a vacuum filtration device. After the suspension on the upper surface of the porous carbon matrix was dried, the suspension was added dropwise. The cycle was repeated 5 times until the suspension on the upper surface could no longer be absorbed. The matrix was then dried in a 70 ℃ oven for 8 h to obtain a matrix containing a carbon-ceramic synergistic framework.

[0117] Step 4, Precursor Impregnation-Pyrolysis (PIP):

[0118] 60 g of organozzirconium polymer (PZC) was added to 40 g of xylene and magnetically stirred for 1.5 h to obtain a homogeneous PZC solution (precursor solution). Then, the carbon-ceramic synergistic framework matrix obtained in step 3 was immersed in the precursor solution so that the bulk was completely immersed. Vacuum impregnation-drying was performed and repeated 3 times. The dried composite material was placed in a high-temperature furnace for heat treatment. After 9 repeated impregnation-pyrolysis and heat treatment, carbon-ceramic synergistic framework modified C / C composite material was obtained.

[0119] The heat treatment process for preparing C / C-ZrC composite material using the PIP method is as follows: the dried composite material is placed in a high-temperature furnace, argon is introduced as a protective gas, and the equipment is heated to 1550 ℃ for 2 h at a heating rate of 5 ℃ / min, so that the introduced precursor is decomposed and converted into ZrC ceramic.

[0120] Example 5

[0121] A method for preparing a carbon-ceramic synergistic framework modified C / C composite material includes the following steps:

[0122] Step 1: Dissolve 12.0 g of resorcinol and 16 g of 37.5 wt.% formaldehyde solution in 19.6 mL of anhydrous ethanol to obtain a mixture; then add 0.24 g of cetyltrimethylammonium bromide (CTAB) to the mixture and magnetically stir the suspension for 20 min to obtain a transparent initial emulsion.

[0123] Step 2: Immerse the low-density C / C in the initial emulsion obtained in Step 1 to completely submerge the block, then place it in a vacuum drying oven and evacuate it until the pressure inside the oven is below 0.09 MPa, maintain this for 30 min, then cure it by water bath heating, dry it at normal pressure and carbonize it, then place it in a CVI furnace, use argon as a protective gas, and heat the equipment to 1100 ℃ at a heating rate of 5 ℃ / min, then introduce CH4 to deposit PyC for 300 min.

[0124] The curing, drying and carbonization process is as follows: the low-density C / C composite material is cured in an oven at 90 ℃ for 36 h, and then dried at 120 ℃ under normal pressure for 10 h; then it is placed in a tube furnace and heated to 1100 ℃ at 5 ℃ / min and held for 2 h, with argon gas introduced as a protective gas throughout the process, so that the resin gel in the composite material is decomposed into carbon.

[0125] The deposition pyrolysis carbon process is as follows: the argon flow rate is set to 2 L / min during the heating and cooling process, 4 L / min during the deposition process, and the CH4 flow rate is 70 L / min; then the temperature is cooled to room temperature to obtain a porous carbon matrix.

[0126] Step 3, Preparation of the carbon-ceramic synergistic framework matrix:

[0127] 15 g of ZrC powder with a particle size of 1.5 μm was added to 35 g of anhydrous ethanol and stirred to form a uniform suspension. The uniform ZrC suspension was introduced into a porous carbon matrix using a vacuum filtration device. After the suspension on the upper surface of the porous carbon matrix was dried, the suspension was added dropwise. The cycle was repeated 5 times until the suspension on the upper surface could no longer be absorbed. The matrix was then dried in an oven at 100 ℃ for 10 h to obtain a matrix containing a carbon-ceramic synergistic framework.

[0128] Step 4, Precursor Impregnation-Pyrolysis (PIP):

[0129] 60 g of organozirconium polymer (PZC) was added to 40 g of xylene and magnetically stirred for 4 h to obtain a uniform PZC solution (precursor solution). Then, the carbon-ceramic synergistic framework matrix obtained in step 3 was immersed in the precursor solution so that the bulk was completely immersed. Vacuum impregnation-drying was performed and repeated 9 times. The dried composite material was placed in a high-temperature furnace for heat treatment. After 9 repeated impregnation-pyrolysis and heat treatment, carbon-ceramic synergistic framework modified C / C composite material was obtained.

[0130] The heat treatment process for preparing C / C-ZrC composite material using the PIP method is as follows: the dried composite material is placed in a high-temperature furnace, argon is introduced as a protective gas, and the equipment is heated to 1550 ℃ for 3 h at a heating rate of 10 ℃ / min, so that the introduced precursor is decomposed and converted into ZrC ceramic.

[0131] Figure 2 The figure shows the morphology of the porous carbon matrix prepared in Example 1. As can be seen from the figure, the porous carbon has a three-dimensional interconnected pore structure and a continuously stacked carbon particle skeleton. Its pore size and pore wall size can reach the micrometer level. The carbon particles are relatively uniform and have the function of segmenting and refining pores.

[0132] Figure 3 The image shows a SEM image of the carbon matrix containing a carbon-ceramic synergistic framework prepared in Example 1. As can be seen from the image, after filtration, ZrC particles were successfully adsorbed onto the porous carbon framework particles, thereby constructing a 3D reaction interface, which is beneficial to improving interface compatibility.

[0133] Figure 4 The image shows the X-ray diffraction pattern of the carbon-ceramic synergistic skeleton modified C / C composite material prepared in Example 1. As can be seen from the image, a pure ZrC modified C / C composite material was successfully prepared.

[0134] Figure 5 Comparison of SEM images of cross-sections of different composite materials; by Figure 5 It is known that in conventional ZrC ceramic-modified C / C composites, the ZrC ceramic structure is relatively loose, with micropores and cracks, and its structure is not dense enough. At the same time, the ceramic particles inside conventional ZrC ceramic-modified C / C composites are agglomerated, with large particle sizes and a continuous plate-like distribution. In contrast, in C / C composites modified with a carbon-ceramic synergistic framework, the construction of the 3D reaction interface enables the porous carbon framework and ZrC to be dispersed and uniformly distributed, alleviating the phenomenon of uneven infiltration into the ceramic matrix and low ceramic conversion rate. The ZrC ceramic particles are small, tightly bonded, and have an embedded distribution with the porous carbon framework.

[0135] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing a carbon-ceramic synergistic skeleton modified C / C composite material, characterized in that, Includes the following steps: The low-density C / C composite material was immersed in an initial emulsion, and then subjected to heating curing, drying, carbonization and deposition of pyrolytic carbon in sequence to obtain a porous carbon matrix. The ZrC suspension was introduced into a porous carbon matrix by vacuum filtration to obtain a carbon matrix containing a carbon-ceramic synergistic framework. The step of introducing the ZrC suspension into the porous carbon matrix by vacuum filtration is as follows: The ZrC suspension was introduced into the porous carbon matrix using a vacuum filtration device. After the ZrC suspension on the upper surface of the porous carbon matrix was dried, the ZrC suspension was added dropwise. This process was repeated several times until the ZrC suspension on the upper surface of the porous carbon matrix could no longer be absorbed. After drying, a carbon matrix containing a carbon-ceramic synergistic framework was obtained. In the process of obtaining a carbon matrix containing a carbon-ceramic synergistic framework, the drying temperature is 70~100℃ and the time is 8~10h; The cycle is repeated 3 to 5 times; A carbon matrix containing a carbon-ceramic synergistic framework was impregnated in an organozirconium polymer solution, and subjected to several vacuum impregnation-drying and heat treatment processes to obtain a carbon-ceramic synergistic framework modified C / C composite material.

2. The method for preparing a carbon-ceramic synergistic skeleton modified C / C composite material according to claim 1, characterized in that, The curing process is carried out in an oven; the curing temperature is 70~90 ℃ and the time is 24~36 h; the drying is carried out at normal pressure and 80~120 ℃ for 5~10 h.

3. The method for preparing a carbon-ceramic synergistic framework modified C / C composite material according to claim 1, characterized in that, The carbonization parameters are as follows: under an argon atmosphere, the temperature is increased to 750-1000 ℃ at a rate of 2-10 ℃ / min, and held for 2-4 h; The parameters for the deposition pyrolysis carbon treatment are as follows: using argon as a protective gas, the heating equipment is heated to 900-1100 ℃ at a heating rate of 1-5 ℃ / min, followed by CH4 deposition for 40-300 min, and then cooled to room temperature to obtain a porous carbon matrix; wherein, during the heating and cooling processes, the argon flow rate is 1-3 L / min; and during CH4 deposition, the argon flow rate is 2-5 L / min.

4. The method for preparing a carbon-ceramic synergistic skeleton modified C / C composite material according to claim 1, characterized in that, The ZrC suspension is obtained by mixing ZrC powder and anhydrous ethanol; the ZrC powder has a particle size of 100nm~2μm; the mass ratio of ZrC powder to anhydrous ethanol is (5~15)g:(15~35)g.

5. The method for preparing a carbon-ceramic synergistic skeleton modified C / C composite material according to claim 1, characterized in that, The organozirconium polymer solution is obtained by mixing organozirconium polymer and xylene; The stirring method is magnetic stirring; the magnetic stirring time is 1~4 hours; The ratio of the organozirconium polymer to xylene is (60~70) g : (30~40) g.

6. The method for preparing a carbon-ceramic synergistic skeleton modified C / C composite material according to claim 1, characterized in that, The number of cycles of vacuum impregnation-drying and heat treatment is 2 to 9.

7. The method for preparing a carbon-ceramic synergistic skeleton modified C / C composite material according to claim 1, characterized in that, The parameters for the heat treatment are as follows: in an argon atmosphere, the temperature is increased to 1500-1600 ℃ at a heating rate of 5-10 ℃ / min, and heated for 2-3 h.

8. A carbon-ceramic synergistic skeleton modified C / C composite material, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 7.

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