Carbon / carbon composite article, method of making the same, and photovoltaic thermal field device
By combining polystyrene dispersion with modified coatings, the problem of unstable carbon/carbon composite coatings was solved, the adhesion and strength of the coatings were enhanced, and the service life was extended.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUNAN KINGBO CARBON CARBON COMPOSITES CO LTD
- Filing Date
- 2026-03-27
- Publication Date
- 2026-06-09
AI Technical Summary
Existing carbon/carbon composite materials suffer from short service life in photovoltaic thermal fields due to unstable coating quality.
Carbon/carbon composite materials are pretreated by impregnation with polystyrene dispersion, and combined with carbon-based fillers, phenolic resins, aminosilanes and alcohol solvents in modified coatings. The coating is then formed through heat treatment to enhance adhesion and strength.
It improves the adhesion and strength of the coating and extends the service life of carbon/carbon composite products in a thermal field.
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Abstract
Description
Technical Field
[0001] This application relates to the field of composite materials technology, and in particular to a carbon / carbon composite product, a method for preparing the same, and a photovoltaic thermal field device. Background Technology
[0002] Carbon / carbon composites are widely used in photovoltaic thermal fields due to their excellent high-temperature resistance and lightweight properties. However, they are prone to performance degradation in complex environments such as high temperatures, oxidation, or corrosion. Therefore, coating technology has become an important means to improve the service life of carbon / carbon composites. Currently, chemical vapor deposition (CVD) is commonly used to prepare carbon or silicon carbide coatings to improve the performance of carbon / carbon composites. However, the products suffer from short service life in thermal fields due to the instability of coating quality. Summary of the Invention
[0003] Therefore, it is necessary to provide a carbon / carbon composite product, its preparation method, and a photovoltaic thermal field device to extend the service life of the carbon / carbon composite product.
[0004] One aspect of this application provides a method for preparing a carbon / carbon composite article, comprising the following steps:
[0005] Carbon / carbon composite material is impregnated in a polystyrene dispersion;
[0006] The impregnated carbon / carbon composite material is subjected to a first heat treatment.
[0007] A modified coating is applied to the surface of a carbon / carbon composite material after the first heat treatment to obtain an intermediate; wherein the modified coating comprises a carbon-based filler, a phenolic resin, an aminosilane, and an alcohol solvent, and the mass ratio of the phenolic resin, the alcohol solvent, and the aminosilane is (20~25):(74~78.5):(1~1.5).
[0008] The intermediate is subjected to a second heat treatment to obtain a carbon / carbon composite product.
[0009] The above method utilizes a polystyrene-containing dispersion to impregnate and pretreat the carbon / carbon composite material, allowing polystyrene to penetrate into the pores on the surface of the carbon / carbon composite material. A first heat treatment then expands the pores on the surface of the carbon / carbon composite material, completing the pore-opening process. Simultaneously, the polystyrene is carbonized and decomposed into carbon residue during the first heat treatment, providing a skeleton for subsequent coatings, thereby enhancing coating adhesion and strength. In the modified coatings used in the above method, carbon-based fillers can be used as coating fillers to fill the carbonaceous skeleton and enhance coating strength; phenolic resin can be used as a binder, and after the second heat treatment, it can form a carbonaceous skeleton to provide basic strength for the coating; alcohol solvents can be used as diluents and solutions for phenolic resin, and their volatility... The process provides an exhaust channel for coating carbonization; aminosilane, as a dispersant, improves the dispersion stability of carbon-based fillers in phenolic resin, reduces agglomeration, and can promote the formation of carbon skeletons and provide a small amount of carbon source to enhance coating strength during carbonization; controlling the mass ratio of phenolic resin, alcohol solvent and aminosilane at (20~25):(74~78.5):(1~1.5) provides better dispersibility for carbon-based fillers, resulting in fewer coating defects and higher quality; the above method, through the synergistic effect of polystyrene and modified coatings with specific components and their mass ratios, further improves coating quality and extends the service life of carbon / carbon composite products in the thermal field.
[0010] In some embodiments, the polystyrene content in the dispersion is 5% to 10% by mass; and / or,
[0011] The polystyrene has a particle size of 5 μm to 10 μm; and / or,
[0012] The impregnation time is 0.5 h to 2 h; and / or,
[0013] The carbon-based filler has a mass content of 15-20% in the modified coating.
[0014] In some embodiments, the mass ratio of the phenolic resin, alcohol solvent, and aminosilane is (22~24):(75~77):(1~1.5); and / or,
[0015] The coating amount is 0.03 g / cm³. 2 ~0.05g / cm 2 .
[0016] In some embodiments, the polystyrene content in the dispersion is 7% to 8% by mass.
[0017] In some embodiments, the carbon-based filler includes at least one of graphite powder, carbon powder, and silicon carbide powder;
[0018] Optionally, the carbon-based filler comprises a mixture of graphite powder, carbon powder, and silicon carbide powder;
[0019] Optionally, the mass ratio of graphite powder, carbon powder and silicon carbide powder in the carbon-based filler is (80~90):(5~10):(5~10).
[0020] In some embodiments, the graphite powder has a particle size of 300 mesh to 1000 mesh; and / or,
[0021] The particle size of the carbon powder is 2000 mesh to 5000 mesh; and / or,
[0022] The silicon carbide powder has a particle size of 500 mesh to 1000 mesh.
[0023] In some embodiments, the temperature of the first heat treatment is ≥600°C; and / or,
[0024] The duration of the first heat treatment is 0.5h to 4h.
[0025] In some embodiments, the temperature of the second heat treatment is 1150°C to 1200°C; and / or,
[0026] The second heat treatment lasts for 1.5 hours to 2 hours; and / or,
[0027] The atmosphere for the second heat treatment is nitrogen or argon.
[0028] A second aspect of this application provides a carbon / carbon composite article prepared using the method described in the first aspect.
[0029] A third aspect of this application provides a photovoltaic thermal field device, comprising the carbon / carbon composite article described in the second aspect. Detailed Implementation
[0030] To facilitate understanding of this application, a more complete description of the application will be provided below with reference to relevant embodiments. Preferred embodiments of the application are shown herein. However, the application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.
[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0032] Carbon / carbon composites are widely used in photovoltaic thermal fields due to their excellent high-temperature resistance and lightweight properties. However, they are prone to performance degradation in complex environments such as high temperatures, oxidation, or corrosion. Therefore, coatings are often deposited on the surface of carbon / carbon composites to improve their performance. Currently, various coating preparation methods are available on the market, with chemical vapor deposition (CVD) being the most widely used method for preparing carbon or silicon carbide coatings. While CVD coatings offer advantages such as good uniformity and high bonding strength, the process is complex, equipment energy costs are high, production cycles are long, and coating effects are unstable. Furthermore, in silicon carbide coatings, the thermal expansion coefficients of silicon carbide and carbon / carbon materials do not perfectly match, leading to a higher risk of coating defects, making them prone to cracking and peeling in thermal fields, resulting in a shorter service life.
[0033] Based on this, one aspect of this application provides a method for preparing a carbon / carbon composite article, comprising the following steps:
[0034] Carbon / carbon composite material is impregnated in a polystyrene dispersion;
[0035] The impregnated carbon / carbon composite material is subjected to a first heat treatment.
[0036] A modified coating is applied to the surface of a carbon / carbon composite material after the first heat treatment to obtain an intermediate; wherein the modified coating comprises carbon-based filler, phenolic resin, aminosilane and alcohol solvent, and the mass ratio of phenolic resin, alcohol solvent and aminosilane is (20~25):(74~78.5):(1~1.5).
[0037] The intermediate is subjected to a second heat treatment to obtain a carbon / carbon composite product.
[0038] The above method utilizes a polystyrene-containing dispersion to impregnate and pretreat the carbon / carbon composite material, allowing polystyrene to penetrate into the pores on the surface of the carbon / carbon composite material. A first heat treatment then expands the pores on the surface of the carbon / carbon composite material, completing the pore-opening process. Simultaneously, the polystyrene is carbonized and decomposed into carbon residue during the first heat treatment, providing a skeleton for subsequent coatings, thereby enhancing coating adhesion and strength. In the modified coatings used in the above method, carbon-based fillers can be used as coating fillers to fill the carbonaceous skeleton and enhance coating strength; phenolic resin can be used as a binder, and after the second heat treatment, it can form a carbonaceous skeleton to provide basic strength for the coating; alcohol solvents can be used as diluents and solutions for phenolic resin, and their volatility... The process provides an exhaust channel for coating carbonization; aminosilane, as a dispersant, improves the dispersion stability of carbon-based fillers in phenolic resin, reduces agglomeration, and can promote the formation of carbon skeletons and provide a small amount of carbon source to enhance coating strength during carbonization; controlling the mass ratio of phenolic resin, alcohol solvent and aminosilane at (20~25):(74~78.5):(1~1.5) provides better dispersibility for carbon-based fillers, resulting in fewer coating defects and higher quality; the above method, through the synergistic effect of polystyrene and modified coatings with specific components and their mass ratios, further improves coating quality and extends the service life of carbon / carbon composite products in the thermal field.
[0039] In some embodiments, the polystyrene dispersion is prepared by dispersing polystyrene microspheres in an alcohol solvent.
[0040] Furthermore, ethanol is used as the alcohol solvent.
[0041] In some embodiments, the polystyrene content in the dispersion is 5% to 10% by mass.
[0042] As an example, the mass content of polystyrene in the dispersion can be 5%, 6%, 7%, 8%, 9% or 10%, or it can be within the range formed by any two of the above point values as endpoints.
[0043] Furthermore, the polystyrene content in the dispersion is 7% to 8% by mass. At this mass content, it can provide sufficient skeleton material for subsequent coatings and leave room for the penetration of modified coatings, thereby further enhancing the coating strength and adhesion.
[0044] In some embodiments, the polystyrene has a particle size of 5 μm to 10 μm.
[0045] In some embodiments, a polystyrene dispersion is used to impregnate a carbon / carbon composite material for 0.5 h to 2 h.
[0046] In some embodiments, the carbon-based filler has a mass content of 15% to 20% in the modified coating.
[0047] Furthermore, in the modified coating, the mass ratio of carbon-based filler to mobile phase is (15~20):(80~85), wherein the mobile phase includes phenolic resin, alcohol solvent and aminosilane.
[0048] In some embodiments, the mass ratio of the phenolic resin, alcohol solvent, and aminosilane is (22~24):(75~77):(1~1.5). Modified coatings prepared with this mass ratio exhibit better coating uniformity and density, fewer coating defects, a glossy surface with no color difference, and further improved coating strength and adhesion, resulting in a longer service life of carbon / carbon composite products in thermal environments.
[0049] In some embodiments, the coating amount is 0.03 g / cm³. 2 ~0.05g / cm 2 .
[0050] In some embodiments, the polystyrene content in the dispersion is 7% to 8% by mass.
[0051] In some embodiments, the carbon-based filler includes at least one of graphite powder, carbon powder, and silicon carbide powder.
[0052] Furthermore, the carbon-based filler comprises a mixture of graphite powder, carbon powder, and silicon carbide powder. Graphite powder can improve the lubricity and thermal conductivity of the carbon-based filler, carbon powder can fill pores to increase density, and silicon carbide powder can enhance hardness and oxidation resistance.
[0053] Furthermore, the mass ratio of graphite powder, carbon powder, and silicon carbide powder in the carbon-based filler is (80~90):(5~10):(5~10). In carbon / carbon composite products made with carbon-based fillers using this mass ratio, thermal stress between the coating and the substrate is alleviated, the risk of coating cracking is reduced, and good thermal stability and thermal shock resistance are maintained.
[0054] As an example, the mass ratio of graphite powder, carbon powder, and silicon carbide powder can be 80:10:10, 85:7.5:7.5, or 90:5:5, or it can be within the range formed by any two of the above point values as endpoints.
[0055] In some embodiments, the graphite powder may be lithium-ion battery graphite powder.
[0056] In some embodiments, the toner may be pyrolytic toner.
[0057] In some embodiments, the graphite powder has a particle size of 300 mesh to 1000 mesh.
[0058] As an example, the particle size of graphite powder can be 300 mesh, 350 mesh, 400 mesh, 450 mesh, 500 mesh, 550 mesh, 600 mesh, 650 mesh, 700 mesh, 750 mesh, 800 mesh, 850 mesh, 900 mesh, 950 mesh, or 1000 mesh, or it can be within the range formed by any two of the above point values as endpoints.
[0059] Furthermore, the particle size of the graphite powder is 500-600 mesh.
[0060] In some embodiments, the particle size of the toner is 2000 mesh to 5000 mesh.
[0061] As an example, the particle size of the toner can be 2000 mesh, 2100 mesh, 2200 mesh, 2300 mesh, 2400 mesh, 2500 mesh, 2600 mesh, 2700 mesh, 2800 mesh, 2900 mesh, 3000 mesh, 3100 mesh, 3200 mesh, 3300 mesh, 3400 mesh, 3500 mesh, 3600 mesh, 3700 mesh, 3800 mesh, 3900 mesh, 4000 mesh, 4100 mesh, 4200 mesh, 4300 mesh, 4400 mesh, 4500 mesh, 4600 mesh, 4700 mesh, 4800 mesh, 4900 mesh, or 5000 mesh, or it can be within the range formed by any two of the above point values as endpoints.
[0062] Furthermore, the particle size of the toner is 3000 mesh to 3500 mesh.
[0063] In some embodiments, the silicon carbide powder has a particle size of 500 mesh to 1000 mesh.
[0064] As an example, the particle size of silicon carbide powder can be 500 mesh, 550 mesh, 600 mesh, 650 mesh, 700 mesh, 750 mesh, 800 mesh, 850 mesh, 900 mesh, 950 mesh or 1000 mesh, or it can be within the range formed by any two of the above point values as end values.
[0065] Furthermore, the particle size of the silicon carbide powder is 700-800 mesh.
[0066] In some embodiments, the carbon-based filler comprises graphite powder with a particle size of 500-600 mesh, carbon powder with a particle size of 3000-3500 mesh, and silicon carbide powder with a particle size of 700-800 mesh. Coatings prepared with this particle size distribution of carbon-based filler exhibit better strength, adhesion, oxidation resistance at 950°C, and thermal shock resistance at 1600°C.
[0067] In some embodiments, the temperature of the first heat treatment is ≥600°C.
[0068] Furthermore, the temperature of the first heat treatment is 600℃~1000℃.
[0069] In some embodiments, the first heat treatment time is 0.5h to 4h.
[0070] In some embodiments, the temperature of the second heat treatment is 1150°C to 1200°C.
[0071] In some embodiments, the second heat treatment lasts for 1.5 to 2 hours.
[0072] In some embodiments, the atmosphere for the second heat treatment is nitrogen or argon.
[0073] A second aspect of this application provides a carbon / carbon composite article prepared using the method described in the first aspect.
[0074] In some embodiments, the structure of the carbon / carbon composite article includes a carbon / carbon composite material and a modified coating on the surface. The carbon / carbon composite material can be a raw material or a molded carbon / carbon composite preform, such as an uncoated carbon / carbon crucible.
[0075] Furthermore, the modified coating covers the entire surface of the carbon / carbon composite material.
[0076] A third aspect of this application provides a photovoltaic thermal field device, comprising the carbon / carbon composite article described in the second aspect.
[0077] Photovoltaic thermal field equipment includes, but is not limited to, crucibles, flow guides, insulation cylinders, crucible supports, central shafts, heaters, support rings, and protective plates for photovoltaic thermal fields.
[0078] To make the objectives, technical solutions, and advantages of this application clearer and more concise, the following specific embodiments are used for illustration, but this application is by no means limited to these embodiments. The embodiments described below are merely preferred embodiments of this application and can be used to describe this application, but should not be construed as limiting the scope of this application. It should be noted that any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.
[0079] To better illustrate this application, the following description, in conjunction with specific embodiments, further explains its content. The following are specific embodiments.
[0080] Example 1
[0081] Step 1, prepare suspension: Disperse polystyrene (PS) microspheres (particle size 5μm~10μm) in ethanol solution to prepare a suspension with a polystyrene content of 5% by mass;
[0082] Step 2, carbon / carbon crucible surface pretreatment: Immerse the carbon / carbon crucible in the suspension prepared in step 1 for 1 hour to allow polystyrene microspheres to penetrate into the pores on the surface of the carbon / carbon crucible, then remove and dry;
[0083] Step 3, carbonization (first heat treatment): The carbon / carbon crucible obtained in step 2 is placed in a high-temperature furnace for carbonization at a temperature of 800℃ for 2 hours. This process opens the surface of the crucible, and the polystyrene decomposes into carbon residue after carbonization, providing a skeleton for the subsequent coating and enhancing the adhesion and strength of the coating.
[0084] Step 4, Prepare the coating:
[0085] A carbon-based filler is prepared by mixing lithium-ion battery graphite powder, pyrolytic carbon powder and silicon carbide powder; wherein, by mass ratio, lithium-ion battery graphite powder: pyrolytic carbon powder: silicon carbide powder = 85: 7.5: 7.5, the particle size of lithium-ion battery graphite powder is 500 mesh, the particle size of pyrolytic carbon powder is 3000 mesh, and the particle size of silicon carbide powder is 700 mesh.
[0086] An alcohol-soluble thermosetting phenolic resin (TA-02), ethanol, and aminosilane (KH550) were mixed to form a mobile phase, wherein, by mass ratio, the ratio of alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) was 23:76:1, and the residual char rate of the alcohol-soluble thermosetting phenolic resin was ≥50%.
[0087] A modified coating was prepared by mixing carbon-based filler with a mobile phase at a mass ratio of 18:82.
[0088] Step 5: Using the paint prepared in Step 4, apply 0.03g / cm³ of the mixture with a brush. 2 The modified coating was uniformly applied to the entire surface (outer and inner surfaces) of the carbon / carbon crucible. After coating, the crucible was placed in a high-temperature carbonization furnace for 1.5 hours at a temperature of 1150°C. Nitrogen gas was introduced during the operation of the carbonization furnace to obtain a carbon / carbon crucible with a coating thickness of 0.25 mm.
[0089] Example 2
[0090] Example 2 is basically the same as Example 1, except that: the coating formulation in step four (by mass ratio) is as follows: in the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 20:78.5:1.5; in the solute, lithium battery graphite powder: pyrolytic carbon powder: silicon carbide powder = 80:10:10; in the coating, solution: solute = 80:20.
[0091] Example 3
[0092] Example 3 is basically the same as Example 1, except that: the coating formulation in step four (by mass ratio) is as follows: in the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 25:74:1; in the solute, lithium battery graphite powder: pyrolytic carbon powder: silicon carbide powder = 90:5:5; in the coating, solution: solute = 85:15.
[0093] Example 4
[0094] Example 4 is basically the same as Example 1, except that the mass content of polystyrene in the suspension in step one is 7.5%.
[0095] Example 5
[0096] Example 5 is basically the same as Example 1, except that the mass content of polystyrene in the suspension in step one is 7.5%.
[0097] The coating formulation for step four (by mass ratio): In the solution, the ratio of alcohol-soluble thermosetting phenolic resin to ethanol to aminosilane (KH550) is 20:78.5:1.5; In the solute, the ratio of lithium-ion battery graphite powder to pyrolytic carbon powder to silicon carbide powder is 80:10:10; In the coating, the ratio of solution to solute is 80:20.
[0098] Example 6
[0099] Example 6 is basically the same as Example 1, except that the mass content of polystyrene in the suspension of step one is 7.5%. The coating formulation in step four (by mass ratio): In the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 25:74:1; In the solute, lithium-ion graphite powder: pyrolytic carbon powder: silicon carbide powder = 90:5:5; In the coating, solution: solute = 85:15.
[0100] Example 7
[0101] Example 7 is basically the same as Example 1, except that the mass content of polystyrene in the suspension in step one is 10%.
[0102] Example 8
[0103] Example 8 is basically the same as Example 1, except that the mass content of polystyrene in the suspension in step one is 10%. The coating formulation in step four (by mass ratio): In the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 20:78.5:1.5; In the solute, lithium-ion graphite powder: pyrolytic carbon powder: silicon carbide powder = 80:10:10; In the coating, solution: solute = 80:20.
[0104] Example 9
[0105] Example 9 is basically the same as Example 1, except that the mass content of polystyrene in the suspension of step one is 10%. The coating formulation of step four (by mass ratio): In the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 25:74:1; In the solute, lithium battery graphite powder: pyrolytic carbon powder: silicon carbide powder = 90:5:5; In the coating, solution: solute = 85:15.
[0106] Example 10
[0107] Example 10 is basically the same as Example 1, except that: the coating formulation in step four (by mass ratio) is: in the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 25:74:1.
[0108] Comparative Example 1
[0109] Comparative Example 1 is basically the same as Example 2, except that: the coating formulation in step four (by mass ratio) is: in the solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 15:83:2.
[0110] Comparative Example 2
[0111] Comparative Example 2 is basically the same as Example 1, except that: the coating formulation in step four (by mass ratio) is as follows: in solution, alcohol-soluble thermosetting phenolic resin: ethanol: aminosilane (KH550) = 30: 68.5: 1.5; in coating, solution: solute = 80: 20.
[0112] Comparative Example 3
[0113] The process is basically the same as in Example 1, except that steps one, two and three are omitted, and the coating is directly prepared to coat the carbon / carbon crucible.
[0114] The carbon / carbon composite products prepared in each embodiment and comparative example were subjected to performance tests. The coating performance was evaluated according to the evaluation items in Table 1. The evaluation criteria for coating performance were qualified and unqualified. A qualified coating is sufficient for use in a photovoltaic thermal field. A qualified coating must meet all performance evaluation items. A coating is unqualified if any one of the performance evaluation items fails. The extended service life in days refers to the number of days that the crucibles prepared in the embodiments and comparative examples have an extended service life compared to the crucibles without coating. The test results are shown in Table 2 below.
[0115] Among them, ash content test: Determination of ash content of carbon materials - GB / T 1429-2009.
[0116] Antioxidant properties test: Test method for antioxidant properties of carbon materials - GB / T 13465-2022.
[0117] Thermal shock resistance test: "Carbon materials - Test method for thermal shock resistance" - ISO 12987:2021.
[0118] Service life extension test: The service life of the coated carbon / carbon crucible of this application is extended by the number of days compared with the uncoated carbon / carbon crucible.
[0119] Table 1
[0120]
[0121] Table 2
[0122]
[0123] In Table 2, A represents the mass ratio of alcohol-soluble thermosetting phenolic resin, ethanol, and aminosilane in the mobile phase during the preparation of the modified coating; B represents the mass ratio of lithium-ion battery graphite powder, pyrolytic carbon powder, and silicon carbide powder in the solid phase of the modified coating.
[0124] As shown in Table 2 above, the carbon / carbon composite products (crucibles) prepared in Examples 1-10 have high coating quality, and the service life of the crucibles in the thermal field is extended by more than 50 days. The solvent composition ratio in the coatings of Comparative Examples 1-2 is incorrect, and in Comparative Example 3, the crucible was not pretreated by impregnation with a suspension containing polystyrene, resulting in unqualified coating quality. Neither of these examples can achieve the technical effect of this application.
[0125] Furthermore, comparing Examples 4 and 7 with Example 1, it can be seen that when the mass content of polystyrene in the suspension is 7%~8%, the crucible has a longer service life. Comparing Example 10 with Example 1, it can be seen that when the mass ratio of phenolic resin, alcohol solvent and aminosilane in the solvent of the coating is (22~24):(75~77):(1~1.5), the crucible has a longer service life.
[0126] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0127] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A method for preparing a carbon / carbon composite product, characterized in that, Includes the following steps: Carbon / carbon composite material is impregnated in a polystyrene dispersion; The impregnated carbon / carbon composite material is subjected to a first heat treatment. A modified coating is applied to the surface of a carbon / carbon composite material after the first heat treatment to obtain an intermediate; wherein the modified coating comprises a carbon-based filler, a phenolic resin, an aminosilane, and an alcohol solvent, and the mass ratio of the phenolic resin, the alcohol solvent, and the aminosilane is (20~25):(74~78.5):(1~1.5). The intermediate is subjected to a second heat treatment to obtain a carbon / carbon composite product.
2. The method for preparing the carbon / carbon composite product as described in claim 1, characterized in that, The dispersion contains 5% to 10% polystyrene by mass; and / or, The polystyrene has a particle size of 5 μm to 10 μm; and / or, The impregnation time is 0.5 h to 2 h; and / or, The carbon-based filler has a mass content of 15-20% in the modified coating.
3. The method for preparing the carbon / carbon composite product as described in claim 1, characterized in that, The mass ratio of the phenolic resin, alcohol solvent, and aminosilane is (22~24):(75~77):(1~1.5); and / or, The coating amount is 0.03 g / cm³. 2 ~0.05g / cm 2 .
4. The method for preparing the carbon / carbon composite product as described in claim 2, characterized in that, The polystyrene content in the dispersion is 7% to 8% by mass.
5. The method for preparing the carbon / carbon composite product as described in claim 1, characterized in that, The carbon-based filler includes at least one of graphite powder, carbon powder, and silicon carbide powder; Optionally, the carbon-based filler comprises a mixture of graphite powder, carbon powder, and silicon carbide powder; Optionally, the mass ratio of graphite powder, carbon powder and silicon carbide powder in the carbon-based filler is (80~90):(5~10):(5~10).
6. The method for preparing the carbon / carbon composite product as described in claim 5, characterized in that, The graphite powder has a particle size of 300 mesh to 1000 mesh; and / or, The particle size of the carbon powder is 2000 mesh to 5000 mesh; and / or, The silicon carbide powder has a particle size of 500 mesh to 1000 mesh.
7. The method for preparing the carbon / carbon composite article according to any one of claims 1 to 5, characterized in that, The temperature of the first heat treatment is ≥600℃; and / or, The duration of the first heat treatment is 0.5h to 4h.
8. The method for preparing the carbon / carbon composite article according to any one of claims 1 to 5, characterized in that, The temperature of the second heat treatment is 1150℃~1200℃; and / or, The second heat treatment lasts for 1.5 hours to 2 hours; and / or, The atmosphere for the second heat treatment is nitrogen or argon.
9. A carbon / carbon composite product, characterized in that, It is prepared by the method described in any one of claims 1 to 8.
10. A photovoltaic thermal field device, characterized in that, Includes the carbon / carbon composite article as described in claim 9.