A c / c-sic-(hfszr3nbi tai)c10-sic composite material, a preparation method and application thereof

Abstract

This invention discloses a C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The present invention relates to SiC composite materials, their preparation methods, and applications. This involves impregnating a C / C preform with a low-viscosity SiC precursor, followed by curing and pyrolysis under an inert atmosphere to coat the C / C preform with a layer of SiC ceramic, thus avoiding the formation of (Hf5Zr3Nb1Ta1)C. 10 The carbon fiber is damaged by the carbothermic reduction reaction during precursor pyrolysis; secondly, this invention employs a combination of multiple inorganic treatments, followed by low-temperature ceramization, and finally high-temperature ceramization, reducing the exposure time of carbon fibers at high temperatures; furthermore, this invention introduces (Hf5Zr3Nb1Ta1)C 10 After ceramic coating, a high-solids-content SiC precursor was further impregnated, and the mechanical properties of the composite material were further synergistically improved by SiC coating.

Description

Technical Field

[0001] This invention belongs to the field of ultra-high temperature ceramic matrix composite material preparation technology, and relates to a C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite materials, their preparation methods, and applications. Background Technology

[0002] During flight, the nose and leading edge of next-generation aircraft (with speeds greater than Mach 5) are subjected to severe high-temperature heat flux impacts. Therefore, their materials must possess properties such as high-temperature structural load-bearing capacity, ablation resistance, oxidation resistance, and thermal shock resistance. Ultra-high temperature ceramic matrix composites are among the most promising materials currently available to meet these requirements.

[0003] As a crucial component of ceramic matrix composites, the composition and microstructure of the ceramic matrix have a vital influence on the mechanical and ablation resistance properties of the composites. Recent research indicates that high-entropy carbide ceramics, due to their thermodynamic high-entropy effect, structural lattice distortion effect, kinetic hysteresis diffusion effect, and performance "cocktail" effect, exhibit exceptional stability under extreme temperature, pressure, and chemical environments, and demonstrate superior high-temperature mechanical properties and oxidation ablation resistance compared to single-phase ultra-high-temperature ceramics. Therefore, ceramic matrix composites based on high-entropy carbides are expected to possess superior performance compared to low-entropy ZrC or HfC ceramic matrix composites.

[0004] Currently, methods for composite materials of continuous carbon fibers and high-entropy carbide ceramics include slurry coating-lamination, metal reactive infiltration, and precursor impregnation-pyrolysis. Among these, the slurry coating-lamination method involves coating a two-dimensional fiber cloth with a ceramic slurry, and then using a lamination device to prepare the composite material under high pressure and high temperature. For example, Zhang L, Wang W, Zhou N, et al. Low temperature fabrication of C f / BN i / (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2 C-SiC mhigh entropy ceramic matrix composite by slurrycoating and laminating combined with precursor infiltration and pyrolysis. Journal of the European Ceramic Society, 2022, 42(7):3099-106.) reported that (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2 A slurry is prepared from C powder, SiC powder, and ethanol, and then coated onto a two-dimensional fiber cloth with a BN coating using a casting method. The fiber cloth is then stacked and pressed into a composite material preform, which is subsequently densified by impregnation and pyrolysis of a silicon carbide precursor. This method has advantages such as low preparation temperature and short preparation cycle, but it cannot be used to prepare large-sized irregularly shaped components. The metal reactive infiltration method involves melting a metal at high temperature and introducing it into a C / C preform, where it reacts with pyrolytic carbon to generate a ceramic phase. For example, patent application CN115477545B discloses laying a high-entropy alloy on the surface of a porous carbon / carbon composite preform, heating it under an inert atmosphere until the high-entropy alloy melts and holding it at that temperature to allow the molten high-entropy alloy to fully infiltrate the porous carbon / carbon composite preform, and then cooling it to obtain a continuous carbon fiber reinforced high-entropy ceramic composite material. This method features a short process cycle and low cost. However, because the high-entropy alloy reacts in situ with porous carbon at high temperatures to form high-entropy carbide ceramics, it can damage the carbon fibers, thus affecting the mechanical properties of the final composite material. Furthermore, due to the interfacial reaction between metal powder and porous materials, this method is prone to incomplete reactions and uneven material composition when preparing large-sized parts, affecting the overall performance of the material. The precursor impregnation pyrolysis method introduces a high-entropy ceramic precursor into a C / C preform, followed by curing and high-temperature ceramicization to prepare ceramic matrix composites. This method has advantages such as simple equipment requirements, low preparation cost, and no environmental pollution, making it an ideal method for preparing large-sized, complex-shaped ceramic matrix composites. However, the current precursor impregnation pyrolysis method for preparing ultra-high temperature ceramic matrix composites requires repeated impregnation and high-temperature pyrolysis processes. The high-temperature pyrolysis process can damage the carbon fibers, thus affecting the mechanical properties of the final composite material. On the other hand, the carbothermic reduction process that occurs during the high-temperature pyrolysis of the ultra-high temperature ceramic precursor can also damage the carbon fibers, thus affecting the mechanical properties of the composite material. In addition, the ceramic matrix obtained from the pyrolysis of ultra-high temperature precursors is mostly granular, which results in poor compressive properties of the composite material. Summary of the Invention

[0005] To address the issues of excessive high-temperature exposure during the preparation of high-entropy ceramic matrix composites using the existing precursor impregnation pyrolysis method, which significantly impacts carbon fibers, damages carbon fibers during precursor pyrolysis, and results in low mechanical properties due to the non-density of precursor pyrolysis products, this invention provides a composite material. The composite material is a C / C-SiC-(Hf5Zr3Nb1Ta1)C composite material with a sandwich structure. 10 -SiC composite material.

[0006] According to an embodiment of the present invention, the composite material comprises a C / C preform and a SiC coating covering the outside of the C / C preform, and (Hf5Zr3Nb1Ta1)C coating covering the outside of the SiC coating. 10 Ceramic and coated with (Hf5Zr3Nb1Ta1)C 10 The SiC ceramic on the outside of the ceramic.

[0007] According to an embodiment of the present invention, the thickness of the SiC coating covering the outside of the C / C preform is 500 nm to 1 μm.

[0008] According to an embodiment of the present invention, the composite material is a carbon fiber reinforced high-entropy carbide ceramic matrix composite material.

[0009] This invention also provides a method for preparing the above-mentioned composite material, comprising sequentially introducing a SiC coating and (Hf5Zr3Nb1Ta1)C coating onto a C / C preform using a precursor impregnation pyrolysis method. 10 Ceramic and SiC ceramics were used to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C with a sandwich structure. 10 -SiC composite material.

[0010] According to an embodiment of the present invention, the method for preparing the composite material includes the following steps:

[0011] (1) Impregnate C / C preform with low viscosity SiC precursor, and cure and decompose under inert atmosphere;

[0012] (2) Repeat step (1) to obtain C / C-SiC blank;

[0013] (3) Using (Hf5Zr3Nb1Ta1)C 10 The C / C-SiC preform obtained by the precursor impregnation step (2) is cured in an air atmosphere and then inorganicated in an inert atmosphere;

[0014] (4) Repeat step (3) and heat to the first ceramization temperature to ceramize;

[0015] (5) Repeat step (4) and raise the temperature to the second ceramization temperature to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C.10 Composite materials;

[0016] (6) Impregnate the C / C-SiC-(Hf5Zr3Nb1Ta1)C obtained in step (5) with a high-viscosity SiC precursor. 10 Composite materials, cured and decomposed under an inert atmosphere;

[0017] (7) Repeat step (6) to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material.

[0018] In one embodiment of the present invention, in step (1), the low-viscosity SiC precursor is a polycarbosilane solution. For example, the viscosity of the polycarbosilane solution is 5–15 mPa·s, exemplarily 5 mPa·s, 10 mPa·s, and 15 mPa·s; the solid content of the polycarbosilane solution is 30–50%, exemplarily 30%, 40%, and 50%.

[0019] In this invention, the viscosity of the solution is measured using a rotational viscometer.

[0020] In one embodiment of the present invention, in step (1), the C / C preform is prepared by depositing carbon on the carbon fiber fabric using a vapor deposition method, with carbon as the raw material.

[0021] In one embodiment of the present invention, in step (1), the impregnation is, for example, vacuum impregnation followed by pressure impregnation. The impregnation temperature is, for example, room temperature. The vacuum impregnation time is, for example, 1 to 4 hours, exemplarily 1 hour, 2 hours, 3 hours, or 4 hours; the vacuum impregnation pressure is -0.099 MPa. The pressure impregnation time is, for example, 1 to 4 hours, exemplarily 1 hour, 2 hours, 3 hours, or 4 hours; the pressure impregnation pressure is 1 to 5 MPa, exemplarily 1 MPa, 3 MPa, or 5 MPa.

[0022] In one embodiment of the present invention, in step (1), the curing temperature is 200-300°C, for example 200°C, 250°C, or 300°C; and the curing time is 1-4 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours.

[0023] In one embodiment of the present invention, in step (1), the pyrolysis temperature is 900 to 1200°C, for example 900°C, 1000°C, 1100°C, or 1200°C; the pyrolysis time is 1 to 4 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours.

[0024] In one embodiment of the present invention, in step (2), the number of repetitions is 2 to 3 times, for example 2 times or 3 times.

[0025] In one embodiment of the present invention, in step (3), the impregnation is, for example, vacuum impregnation followed by pressure impregnation. The impregnation temperature is, for example, room temperature. The vacuum impregnation time is, for example, 1 to 4 hours, exemplarily 1 hour, 2 hours, 3 hours, or 4 hours; the vacuum impregnation pressure is -0.099 MPa. The pressure impregnation time is, for example, 1 to 4 hours, exemplarily 1 hour, 2 hours, 3 hours, or 4 hours; the pressure impregnation pressure is 1 to 5 MPa, exemplarily 1 MPa, 3 MPa, or 5 MPa.

[0026] In one embodiment of the present invention, in step (3), the curing temperature is 200-300°C, for example 200°C, 250°C, or 300°C; and the curing time is 1-4 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours.

[0027] In one embodiment of the present invention, in step (3), the inorganication temperature is 500 to 700°C, for example 500°C, 600°C, or 700°C; the inorganication time is 1 to 4 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours.

[0028] In one embodiment of the present invention, in step (3), the (Hf5Zr3Nb1Ta1)C 10 The precursor can be prepared according to the methods disclosed in CN111471268B and / or CN111303581B.

[0029] According to an embodiment of the present invention, in step (1), the (Hf5Zr3Nb1Ta1)C 10 The precursor was prepared by mixing an alkoxide copolymer of metals Hf, Zr, Nb, and Ta as the metal source and allyl phenolic aldehyde as the carbon source.

[0030] In one embodiment of the present invention, the total molar number of metals in the alkoxide copolymer of metals Hf, Zr, Nb, and Ta is in the weight ratio of allyl phenolic aldehyde to 1 mol: (17-40) g.

[0031] According to an exemplary embodiment of the present invention, the (Hf5Zr3Nb1Ta1)C 10 The preparation method of the precursor includes the following steps:

[0032] (a) Preparation of metal alkoxide complex: A complexing agent is added dropwise to a metal alkoxide M(OR)n, and stirring is continued for 0.1 to 5 h after the addition is complete to obtain the metal alkoxide complex; wherein: M is selected from Hf, Zr, Nb or Ta;

[0033] (b) Co-hydrolysis: Select the metal alkoxide complex prepared in step (1), mix them, add a mixture of water and monohydric alcohol dropwise, and reflux for 1-5 hours after the addition is complete to obtain a metal alkoxide copolymer solution.

[0034] (c) Preparation of precursor: Allylphenol is added to the metal alkoxide copolymer solution obtained in step (2), and after mixing, the (Hf5Zr3Nb1Ta1)C is obtained. 10 Precursor.

[0035] In one embodiment of the present invention, in step (a), the molar ratio of the metal alkoxide and the complexing agent is 1:(0.15~0.5)n; when M in the metal alkoxide is selected from Zr or Hf, n is 4; when M in the metal alkoxide is selected from Nb or Ta, n is 5.

[0036] In one embodiment of the invention, the complexing agent is acetylacetone and / or ethyl acetoacetate.

[0037] In one embodiment of the present invention, in step (a), the temperature at which the complexing agent is added is room temperature to 80°C.

[0038] In one embodiment of the present invention, in step (b), the molar ratio of the metal alkoxide complexes of Hf, Zr, Nb and Ta is 5:3:1:1.

[0039] In one embodiment of the present invention, in step (b), the total molar ratio of water to metal elements is (0.8 to 1.3):1, with exemplary ratios being 0.8:1, 1.0:1, 1.2:1, and 1.3:1.

[0040] In one embodiment of the present invention, in step (b), the mass ratio of monohydric alcohol to water is 3 to 8:1, for example 3:1, 5:1, or 8:1.

[0041] In one embodiment of the present invention, in step (b), the monohydric alcohol is selected from one or more of methanol, ethanol, isopropanol, n-propanol, n-butanol, isobutanol, ethylene glycol methyl ether, and ethylene glycol ethyl ether.

[0042] In one embodiment of the present invention, in step (b), the temperature at which the mixture of water and monohydric alcohol is added is room temperature to 90°C.

[0043] In one embodiment of the present invention, in step (4), the temperature of the first ceramization is 1450 to 1600°C, for example 1450°C, 1500°C, or 1600°C; and the time of the first ceramization is 1 to 5 hours.

[0044] In one embodiment of the present invention, in step (4), the first ceramization is performed under vacuum conditions.

[0045] In one embodiment of the present invention, in step (4), the number of repetitions is 3 to 5 times, for example 3 times, 4 times, or 5 times.

[0046] In one embodiment of the present invention, in step (5), the temperature of the second ceramization is 1800-1900°C, for example 1800°C, 1850°C, or 1900°C; and the time of the second ceramization is 1-3 hours.

[0047] In one embodiment of the present invention, in step (5), the second ceramization is performed under vacuum conditions.

[0048] In one embodiment of the present invention, in step (5), the number of repetitions is 1 to 4 times, for example 2 times or 3 times.

[0049] In one embodiment of the present invention, in step (6), the high-viscosity SiC precursor is a polycarbosilane solution with a viscosity of 80-180 mPa·s, exemplarily 80 mPa·s, 100 mPa·s, 120 mPa·s, 150 mPa·s, and 180 mPa·s; the solid content of the polycarbosilane solution is 55-65%, exemplarily 55%, 60%, and 65%.

[0050] In one embodiment of the present invention, in step (6), the impregnation is, for example, vacuum impregnation followed by pressure impregnation. The impregnation temperature is, for example, room temperature. The vacuum impregnation time is, for example, 1 to 4 hours, exemplarily 1 hour, 2 hours, 3 hours, or 4 hours; the vacuum impregnation pressure is -0.099 MPa. The pressure impregnation time is, for example, 1 to 4 hours, exemplarily 1 hour, 2 hours, 3 hours, or 4 hours; the pressure impregnation pressure is 1 to 5 MPa, exemplarily 1 MPa, 3 MPa, or 5 MPa.

[0051] In one embodiment of the present invention, in step (6), the curing temperature is 200-300°C; the curing time is 1-4 hours, for example 1 hour, 2 hours, 3 hours, and 4 hours.

[0052] In one embodiment of the present invention, in step (6), the pyrolysis temperature is 900 to 1200°C, for example 900°C, 1000°C, 1100°C, or 1200°C; and the pyrolysis time is 1 to 4 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours.

[0053] In one embodiment of the present invention, in step (7), the number of repetitions is 2 to 8 times, for example 2 times, 3 times, 4 times, 5 times, 6 times, or 8 times.

[0054] In one embodiment of the invention, the inert atmosphere is, for example, argon.

[0055] This invention also provides the above-mentioned C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 - Applications of SiC composite materials in aerospace. For example, their application in aircraft.

[0056] The present invention also provides an aircraft containing the above-mentioned C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite materials and / or materials composed of the above-mentioned C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material was prepared.

[0057] The beneficial effects of this invention are:

[0058] This invention coats a C / C preform with a layer of SiC ceramic by impregnating it with a low-viscosity SiC precursor and then curing and pyrolyzing it under an inert atmosphere. This avoids the formation of (Hf5Zr3Nb1Ta1)C 10 The carbon fiber is damaged by the carbothermic reduction reaction during precursor pyrolysis; secondly, this invention employs a combination of multiple inorganic treatments, followed by low-temperature ceramization, and finally high-temperature ceramization, reducing the exposure time of carbon fibers at high temperatures; furthermore, this invention introduces (Hf5Zr3Nb1Ta1)C 10 After ceramic coating, a high-solids-content SiC precursor was further impregnated, and the mechanical properties of the composite material were further synergistically improved by SiC coating. Attached Figure Description

[0059] Figure 1 C / C-SiC-(Hf5Zr3Nb1Ta1)C prepared in Example 1 10 -Scanning electron microscope and energy dispersive spectroscopy images of SiC composite materials.

[0060] Figure 2 C / C-SiC-(Hf5Zr3Nb1Ta1)C prepared in Example 1 10 X-ray powder diffraction pattern of SiC composite material.

[0061] Figure 3 The C / C-(Hf5Zr3Nb1Ta1)C prepared for Comparative Example 3 10 Scanning electron microscope and energy dispersive spectroscopy images of composite materials. Detailed Implementation

[0062] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0063] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0064] In the following embodiments of the present invention, the C / C porous preform is obtained by depositing carbon fiber fabric (purchased from Jiangsu Tianniao High-Tech Co., Ltd., with needle-punched fiber weaving and a fiber volume content of 28%) as raw material, using a chemical vapor deposition method to deposit carbon on the carbon fiber fabric. The density of the C / C porous preform is 1.08 g / cm³. 3 .

[0065] (Hf5Zr3Nb1Ta1)C 10 The precursor can be prepared according to the methods disclosed in CN111471268B and / or CN111303581B.

[0066] In the following embodiments of the present invention, the (Hf5Zr3Nb1Ta1)C used 10 The preparation method of the precursor is as follows:

[0067] (1) Obtaining metal alkoxides: Select metal alkoxides Zr(OPr)4, Hf(OPr)4, Ta(OPr)5 and Nb(OPr)5. For Ta(OPr)5 and Nb(OPr)5, disperse metal salts TaCl5 and NbCl5 in n-hexane respectively, add monohydric alcohol ethylene glycol ethyl ether dropwise at -10℃, and then add triethylamine dropwise. After the addition is complete, heat and reflux for 1 h, and filter to obtain metal alkoxide solutions. The ratio of metal salt, monohydric alcohol and triethylamine is 1:5:6 and 1:5:6, respectively.

[0068] (2) Preparation of metal alkoxide complexes: Acetylacetone was added dropwise to metal alkoxides Zr(OPr)4, Hf(OPr)4, Ta(OPr)5 and Nb(OPr)5 at room temperature, and stirring was continued for 0.5 h after the addition was completed; the molar ratios of metal alkoxides Zr(OPr)4, Hf(OPr)4, Ta(OPr)5, Nb(OPr)5 and acetylacetone were 1:0.48, 1:0.8, 1:1 and 1:2, respectively;

[0069] (3) Co-hydrolysis: The metal alkoxide complex obtained in step (2) is mixed evenly with Zr, Hf, Ta and Nb metals in a molar ratio of 3:5:1:1. At room temperature, a mixed solution of water and n-propanol is slowly added dropwise to the system, wherein the molar ratio of water to total metals is 1:1 and the mass ratio of n-propanol to water is 4:1. After the addition is complete, the mixture is refluxed for 5 hours to obtain a metal alkoxide copolymer solution.

[0070] (4) Preparation of precursor: The metal alkoxide copolymer obtained in step (3) is mixed evenly with allylphenol aldehyde, the total amount of metal elements in the alkoxide copolymer to the mass ratio of allylphenol aldehyde is 1 mol: 30 g, the mixture is heated to 80 °C, reacted for 1 h, and then cooled to obtain (Zr4Hf6Nb1Ta1)C 12 Ceramic precursor. The metal content of the obtained precursor is 30.5 wt%.

[0071] Example 1

[0072] C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The preparation method of SiC composite material is as follows:

[0073] (1) At room temperature, the C / C porous preform was immersed in a polycarbosilane solution with a solid content of 40% and a viscosity of 10 mPa·s under a vacuum of -0.099 MPa for 2 h. Then, it was immersed in the same polycarbosilane solution under a pressure of 3 MPa for 1 h. The preform after immersion was cured at 250 °C for 2 h under an argon atmosphere, and then inorganicated at 1200 °C for 2 h under an argon atmosphere.

[0074] (2) Repeat step (1) twice to obtain C / C-SiC blank.

[0075] (3) At room temperature, the C / C-SiC preform was impregnated with (Hf5Zr3Nb1Ta1)C under a vacuum of -0.099MPa. 10 The precursor was impregnated for 2 hours, and then impregnated with the above (Hf5Zr3Nb1Ta1)C under a pressure of 3 MPa. 10 The precursor was impregnated for 1 hour. The impregnated preform was cured at 200°C for 2 hours in air, and then inorganicated by holding it at 500°C for 2 hours in argon atmosphere.

[0076] (4) Repeat step (3) 3 times, then heat to 1600℃ under vacuum and hold for 2 hours.

[0077] (5) Repeat step (4) 3 times, raise the temperature to 1800℃ under vacuum and hold for 2 hours to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 Composite materials.

[0078] (6) At room temperature, C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The composite material was impregnated in a polycarbosilane solution with a solid content of 55% and a viscosity of 80 mPa·s under a vacuum of -0.099 MPa for 2 hours, followed by impregnation in the same polycarbosilane solution under a pressure of 3 MPa for 1 hour. The impregnated preform was then cured at 250°C for 2 hours under an argon atmosphere, and subsequently inorganicated at 1200°C for 2 hours under an argon atmosphere.

[0079] (7) Repeat step (6) 6 times to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material.

[0080] Figure 1 These are scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) images of the composite material obtained in this embodiment. As can be seen from the images, the composite material forms SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC sandwich structure, that is, a layer of SiC ceramic is first coated on the outside of a C / C porous preform, and then a layer of (Hf5Zr3Nb1Ta1)C is coated on the outside of the SiC ceramic. 10 Ceramics, ultimately in (Hf5Zr3Nb1Ta1)C 10 The ceramic is coated with a layer of SiC ceramic.

[0081] Figure 2 This embodiment uses C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The X-ray powder diffraction pattern of the SiC ceramic matrix composite material shows that the composite material contains C, SiC, and (Hf5Zr3Nb1Ta1)C. 10 Ceramics are composed of three crystal phases.

[0082] Example 2

[0083] C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The preparation method of SiC composite material is as follows:

[0084] (1) At room temperature, the C / C porous preform was immersed in a polycarbosilane solution with a solid content of 30% and a viscosity of 5 mPa·s under a vacuum of -0.099 MPa for 2 h. Then, it was immersed in the same polycarbosilane solution under a pressure of 3 MPa for 1 h. The preform after immersion was cured at 300 °C for 2 h under an argon atmosphere, and then inorganicated at 900 °C for 2 h under an argon atmosphere.

[0085] (2) Repeat step (1) 3 times to obtain C / C-SiC blank.

[0086] (3) At room temperature, the C / C-SiC preform was impregnated with (Hf5Zr3Nb1Ta1)C under a vacuum of -0.099MPa. 10 The precursor was impregnated for 2 hours, and then impregnated again under a pressure of 3 MPa for 1 hour. The impregnated preform was cured at 250°C for 2 hours in air, and then inorganicated by holding at 700°C for 2 hours in argon atmosphere.

[0087] (4) Repeat step (3) 5 times, then heat to 1500℃ under vacuum and keep warm for 3 hours.

[0088] (5) Repeat step (4) twice, and heat to 1900℃ under vacuum for 1 hour to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 Composite materials.

[0089] (6) At room temperature, C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The composite material was impregnated in a polycarbosilane solution with a solid content of 60% and a viscosity of 150 mPa·s under a vacuum of -0.099 MPa for 2 hours, followed by impregnation in the same polycarbosilane solution under a pressure of 3 MPa for 1 hour. The impregnated preform was then cured at 300°C for 2 hours under an argon atmosphere, and subsequently inorganicated at 1000°C for 2 hours under an argon atmosphere.

[0090] (7) Repeat step (6) 3 times to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material.

[0091] Comparative Example 1

[0092] C / C-(Hf5Zr3Nb1Ta1)C 10 The preparation method of the -SiC composite material differs from that in Example 1 only in that steps (1) and (2) are removed to obtain C / C-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material.

[0093] Comparative Example 2

[0094] C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The preparation method of the composite material differs from that in Example 1 only in that steps (6) and (7) are removed to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 Composite materials.

[0095] Comparative Example 3

[0096] C / C-(Hf5Zr3Nb1Ta1)C 10 The preparation method of the composite material differs from that in Example 1 only in that steps (1), (2), (6), and (7) are removed to obtain C / C-(Hf5Zr3Nb1Ta1)C 10 Composite materials.

[0097] Figure 3 The images show scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) images of the composite material obtained in this comparative example. As can be seen from the images, each metal element is uniformly distributed around the C / C material.

[0098] Comparative Example 4

[0099] C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 The preparation method of SiC composite material is as follows:

[0100] (1) At room temperature, the C / C porous preform was immersed in a polycarbosilane solution with a solid content of 40% and a viscosity of 10 mPa·s under a vacuum of -0.099 MPa for 2 h. Then, it was immersed in the same polycarbosilane solution under a pressure of 3 MPa for 1 h. The preform after immersion was cured at 250 °C for 2 h under an argon atmosphere, and then inorganicated at 1200 °C for 2 h under an argon atmosphere.

[0101] (2) Repeat step (1) twice to obtain C / C-SiC blank.

[0102] (3) At room temperature, the C / C-SiC preform was impregnated with (Hf5Zr3Nb1Ta1)C under a vacuum of -0.099MPa. 10 The precursor was impregnated for 2 hours, and then impregnated again under a pressure of 3 MPa for 1 hour. The impregnated preform was cured at 200°C for 2 hours in air, and then heated to 1800°C under vacuum and held for 2 hours.

[0103] (4) Repeat step (3) 15 times to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 Composite materials.

[0104] (5) At room temperature, C / C-SiC-(Hf5Zr3Nb1Ta1)C 10The composite material was impregnated in a polycarbosilane solution with a solid content of 55% and a viscosity of 10 mPa·s under a vacuum of -0.099 MPa for 2 hours, followed by impregnation in the same polycarbosilane solution under a pressure of 3 MPa for 1 hour. The impregnated preform was then cured at 250°C for 2 hours under an argon atmosphere, and subsequently inorganicated at 1200°C for 2 hours under an argon atmosphere.

[0105] (6) Repeat step (5) 6 times, C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material.

[0106] The mechanical properties of the composite materials obtained in Example 1 and Comparative Examples 1-3 were measured, and the results are shown in Table 1 below.

[0107] Table 1. Comparison of mechanical properties of the material obtained in Example 1 with the materials obtained in Comparative Examples 1-3

[0108]

[0109] Table 1 lists the C / C-SiC-(Hf5Zr3Nb1Ta1)C prepared in Example 1. 10 -SiC composite materials and C / C-(Hf5Zr3Nb1Ta1)C prepared in Comparative Examples 1-3 10 -SiC composite materials, C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 Composite materials and C / C-(Hf5Zr3Nb1Ta1)C 10 The mechanical properties of the composite materials can be compared, and it can be seen that the C / C-SiC-(Hf5Zr3Nb1Ta1)C with the sandwich structure of this invention has better mechanical properties. 10 The SiC composite material exhibits the highest mechanical properties, primarily due to the coating of the C / C preform with a layer of SiC ceramic, which avoids the formation of (Hf5Zr3Nb1Ta1)C. 10 The carbon fiber is damaged by the carbothermic reduction reaction during precursor pyrolysis; simultaneously, this invention reduces the exposure time of carbon fibers at high temperatures by employing a combined treatment method of multiple inorganic treatments, followed by low-temperature ceramization, and finally high-temperature ceramization; furthermore, this invention introduces (Hf5Zr3Nb1Ta1)C 10 After ceramicizing, a high-solids-content SiC precursor was further impregnated, and the introduction of SiC further synergistically improved the mechanical properties of the composite material.

[0110] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite material, characterized in that, The composite material is a C / C-SiC-(Hf5Zr3Nb1Ta1)C composite material with a sandwich structure. 10 -SiC composite material, the composite material comprising a C / C preform and a SiC coating covering the outside of the C / C preform, and (Hf5Zr3Nb1Ta1)C coating covering the outside of the SiC coating. 10 Ceramic and coated with (Hf5Zr3Nb1Ta1)C 10 The SiC ceramic on the outside of the ceramic.

2. The method for preparing the composite material according to claim 1, characterized in that, The preparation method includes sequentially introducing a SiC coating and (Hf5Zr3Nb1Ta1)C onto a C / C preform using a precursor impregnation pyrolysis method. 10 Ceramic and SiC ceramics were used to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C with a sandwich structure. 10 -SiC composite material.

3. The preparation method according to claim 2, characterized in that, Includes the following steps: (1) Impregnate the C / C preform with a low-viscosity SiC precursor, and then cure and decompose it under an inert atmosphere; (2) Repeat step (1) to obtain C / C-SiC blank; (3) Impregnate the C / C-SiC preform obtained in step (2) with (Hf5Zr3Nb1Ta1)C 10 The precursor is cured in an air atmosphere and then inorganicated in an inert atmosphere; (4) Repeat step (3) and heat to the first ceramization temperature to ceramize; (5) Repeat step (4) and raise the temperature to the second ceramization temperature to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C. 10 Composite materials; (6) The C / C-SiC-(Hf5Zr3Nb1Ta1)C obtained in step (5) 10 The composite material was impregnated with a high-viscosity SiC precursor and then cured and pyrolyzed under an inert atmosphere. (7) Repeat step (6) to obtain C / C-SiC-(Hf5Zr3Nb1Ta1)C 10 -SiC composite material.

4. The preparation method according to claim 3, characterized in that, In step (1), the C / C preform is prepared by depositing carbon on carbon fiber fabric using a vapor deposition method. Preferably, in step (1), the low-viscosity SiC precursor is a polycarbosilane solution. Preferably, the viscosity of the polycarbosilane solution is 5–15 mPa·s; and the solid content of the polycarbosilane solution is 30–50%. Preferably, in step (1), the curing temperature is 200-300℃, for example 200℃, 250℃, 300℃; and the curing time is 1-4h, for example 1h, 2h, 3h, 4h. Preferably, in step (1), the pyrolysis temperature is 900–1200°C, and the pyrolysis time is 1–4 h.

5. The preparation method according to claim 3, characterized in that, In step (2), the repetition is performed 2 to 3 times. Preferably, in step (3), the curing temperature is 200-300℃, for example 200℃, 250℃, 300℃; and the curing time is 1-4h, for example 1h, 2h, 3h, 4h. Preferably, in step (3), the inorganication temperature is 500-700℃, for example 500℃, 600℃, or 700℃; the inorganication time is 1-4h, for example 1h, 2h, 3h, or 4h.

6. The preparation method according to claim 3, characterized in that, In step (4), the temperature of the first ceramization is 1450-1600℃; the time of the first ceramization is 1-5h. Preferably, in step (4), the repetition is performed 3 to 5 times.

7. The preparation method according to claim 3, characterized in that, In step (5), the temperature of the second ceramization is 1800-1900℃; the time of the second ceramization is 1-3h. Preferably, in step (5), the repetition is performed 1 to 4 times.

8. The preparation method according to claim 3, characterized in that, In step (6), the high-viscosity SiC precursor is a polycarbosilane solution with a viscosity of 80–180 mPa·s; the solid content of the polycarbosilane solution is 55–65%. Preferably, in step (6), the curing temperature is 200-300°C and the curing time is 1-4 hours. Preferably, in step (6), the pyrolysis temperature is 900–1200°C, and the pyrolysis time is 1–4 h. Preferably, in step (7), the repetition is performed 2 to 8 times.

9. The application of the composite material according to claim 1 and / or the composite material prepared by the preparation method according to any one of claims 2-8 in aerospace.

10. An aircraft, characterized in that, The aircraft contains the composite material of claim 1 and / or is prepared from the composite material.

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