A C / C-(Zr,Hf,Ti)C composite material and its preparation method

Abstract

This invention discloses a C / C-(Zr,Hf,Ti)C composite material and its preparation method, belonging to the technical field of multi-component single-phase ultra-high temperature ceramic modified C / C composite materials. The method disclosed in this invention uses ZrC organic precursor PZC as the zirconium source, HfC organic precursor PHC as the hafnium source, tetrabutyl titanate as the titanium source, and xylene as the solvent. After thorough mixing, a ternary organic precursor solution is obtained. The porous low-density C / C composite material is repeatedly immersed in the ZrC-HfC-TiC ternary ceramic organic precursor solution, dried, and then heat-treated to obtain the C / C-(Zr,Hf,Ti)C composite material. This material fully utilizes the synergistic effect of the ablation resistance of each component ceramic, which is beneficial for extending the service life of the C / C composite material in extreme environments.

Description

Technical Field

[0001] This invention belongs to the technical field of multi-component single-phase ultra-high temperature ceramic modified C / C composite materials, specifically involving a C / C-(Zr,Hf,Ti)C composite material and its preparation method. Background Technology

[0002] Ultra-high temperature ceramics (UHTCs) are a class of high-temperature materials with high melting points, high strength, high hardness, and excellent ablation resistance. They mainly include transition metal carbides, borides, and nitrides. Carbon fiber reinforced carbon matrix composites (C / C composites) have advantages such as low density, small coefficient of thermal expansion, and mechanical properties that increase with increasing temperature. However, C / C composites are easily oxidized in environments exceeding 370°C, leading to a decline in their mechanical properties. Combining UHTCs and C / C composites helps retain the advantages of both, resulting in a modified material with good oxidation and ablation resistance and high-temperature mechanical properties.

[0003] Among ultra-high temperature ceramics, ZrC and HfC have attracted much attention in the field of ultra-high temperature ceramic ablation due to their excellent high-temperature stability. However, the oxide layers formed after high-temperature oxidation of HfC and ZrC ceramics are usually porous, which cannot effectively prevent oxygen from penetrating into the matrix. In addition, the phase transformation of oxides can lead to the accumulation of internal stress in the matrix, increasing the probability of crack formation. In recent years, researchers have adopted an effective solution to improve the integrity of the oxide film formed under high-temperature ablation by developing multi-component ultra-high temperature ceramics. The composite phase oxides formed after the oxidation of multi-component ceramics can not only increase the density of the oxide layer, but also suppress the phase transformation of single-phase oxides and reduce the generation of internal defects in the oxide layer.

[0004] The literature "Jinhua Lu, Kui Hao, Lei Liu, Hejun Li, Kezhi Li, Junling Qu, Xin Yan. Ablation resistance of SiC–HfC–ZrC multiphase modified carbon / carbon composites. Corrosion Science, 103(2016):1-6" reports a SiC–HfC–ZrC ternary multiphase ceramic modified C / C composite material. The study found that the material containing both ZrC and HfC exhibits superior ablation resistance compared to composites containing only ZrC or HfC. However, due to the differences in thermal expansion coefficients among the different ceramic phases, the multiphase ceramic modified C / C composite material is highly susceptible to interfacial cracks and other defects under high-temperature combustion gas erosion conditions, leading to catastrophic failure. Summary of the Invention

[0005] The purpose of this invention is to provide a C / C-(Zr,Hf,Ti)C composite material and its preparation method, in order to solve the technical problem of interfacial cracks caused by multiple interfaces and mismatch of thermal expansion coefficients at high temperatures in multi-component ceramics.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] This invention discloses a method for preparing C / C-(Zr,Hf,Ti)C composite materials, comprising the following steps:

[0008] S1: The porous low-density C / C composite material was immersed in a ZrC-HfC-TiC ternary ceramic organic precursor solution and then vacuum dried to obtain the C / C composite material impregnated with the precursor.

[0009] S2: After drying the C / C composite material impregnated with the precursor, the dried C / C composite material impregnated with the precursor is obtained;

[0010] S3: Repeat steps S1 and S2 several times in sequence, wrap the dried C / C composite material impregnated with the precursor with graphite paper, and then perform heat treatment in an inert atmosphere;

[0011] S4: Repeat steps S1 to S3 several times to finally obtain the C / C-(Zr,Hf,Ti)C composite material.

[0012] Furthermore, the preparation method of the porous low-density C / C composite material is as follows:

[0013] Carbon felt was subjected to chemical vapor deposition (CVD) with hydrocarbon gas as the carbon source and Ar as the carrier and protective gas. After CVD, it was cooled in the furnace to obtain a porous low-density C / C composite material.

[0014] Furthermore, the preparation method of the ZrC-HfC-TiC ternary ceramic organic precursor solution is as follows:

[0015] ZrC precursor powder, HfC precursor powder and TiC precursor are mixed to obtain a mixed precursor; the mixed precursor is mixed with a solvent to obtain a mixed precursor solution; the mixed precursor solution is subjected to ultrasonic vibration to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution.

[0016] Further, the mass ratio of the mixed precursor to the solvent is (1-3):1; the solvent is xylene; the molar ratio of the ZrC precursor powder, HfC precursor powder and TiC precursor is (5-10):(5-10):(1-5);

[0017] The duration of the ultrasonic oscillation is 3 to 5 hours.

[0018] Furthermore, in S1, the process parameters for the vacuum drying process are: evacuate to -0.08 to -0.1 MPa and hold at that pressure for 20 to 30 minutes.

[0019] Furthermore, in S2, the drying temperature is 60–80°C.

[0020] Furthermore, in S3, the number of times steps S1 and S2 are repeated is three times; the process parameters for heat treatment under an inert atmosphere are: using an inert gas as a protective gas, heating to 1600-2100℃ at a rate of 3-5℃ / min, holding at that temperature for 1-3 hours, and then cooling to room temperature at a rate of 2-4℃ / min.

[0021] Furthermore, in S4, the number of times steps S1 to S3 are repeated sequentially is 8 to 11.

[0022] Furthermore, the density of the porous low-density C / C composite material is 1.0–1.3 g / cm³. 3 .

[0023] The present invention also discloses a C / C-(Zr,Hf,Ti)C composite material prepared by the above preparation method.

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

[0025] This invention discloses a method for preparing C / C-(Zr,Hf,Ti)C composite material. The method involves repeatedly immersing a porous, low-density C / C composite material in a ZrC-HfC-TiC ternary ceramic organic precursor solution, followed by drying, and then heat treatment to obtain the C / C-(Zr,Hf,Ti)C composite material. This material fully utilizes the comprehensive ablation resistance of each component ceramic, solving the technical problem of interfacial cracks caused by the mismatch of thermal expansion coefficients at high temperatures in traditional materials. This is beneficial for extending the service life of C / C composite materials in extreme environments.

[0026] Furthermore, this method uses ZrC organic precursor PZC as the zirconium source, HfC organic precursor PHC as the hafnium source, tetrabutyl titanate as the titanium source, and xylene as the solvent. After thorough mixing, a ternary organic precursor solution is obtained. The various materials exert a synergistic effect, which improves the ablation resistance. Moreover, this method is simple to operate and can be applied to complex components, thus broadening the application field of ultra-high temperature ablation.

[0027] The present invention also discloses a C / C-(Zr,Hf,Ti)C composite material prepared by the above preparation method. According to relevant experimental data, after being ablated by an oxyacetylene flame for 90 seconds, the C / C-(Zr,Hf,Ti)C composite material forms a relatively dense oxide film at the ablation center, which blocks the erosion of the matrix by the high-temperature oxygen-containing flow. This proves that the introduction of the ternary single-phase solid solution ceramic (Zr,Hf,Ti)C can effectively improve the ablation resistance of the C / C composite material. Attached Figure Description

[0028] Figure 1 The images shown are low-magnification TEM images, EDS images, and high-magnification TEM images of the (Zr,Hf,Ti)C ceramics prepared in this invention; wherein: a-low-magnification TEM image; b-EDS image corresponding to Figure a; c-high-magnification TEM image;

[0029] Figure 2 The macroscopic morphology of the C / C-(Zr,Hf,Ti)C composite material prepared in this invention is shown.

[0030] Figure 3 The image shows the XRD pattern of the C / C-(Zr,Hf,Ti)C composite material prepared in this invention.

[0031] Figure 4 The image shows the XRD pattern of the ablated surface of the C / C-(Zr,Hf,Ti)C composite material prepared in this invention.

[0032] Figure 5 The macroscopic and ablation center micromorphology of the C / C-(Zr,Hf,Ti)C composite material prepared in this invention are shown. Detailed Implementation

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.”

[0037] 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.

[0038] This invention provides a method for preparing C / C-(Zr,Hf,Ti)C composite materials, comprising the following steps:

[0039] Step 1: Place the clean carbon felt in a chemical vapor deposition furnace, use hydrocarbon gas as carbon source, and Ar as carrier gas and protective gas to carry out chemical vapor deposition. After the process is completed, cool with the furnace to obtain a porous low-density C / C composite material.

[0040] Step 2: Clean the porous low-density C / C composite material obtained in Step 1 with anhydrous ethanol and dry it for later use;

[0041] Step 3: Combine ZrC precursor (PZC), HfC precursor (PHC), and TiC precursor C 16 H 36 O4Ti) is mixed to obtain a mixed precursor; the mixed precursor is mixed with a solvent to obtain a mixed precursor solution; the mixed precursor solution is ultrasonically vibrated for 3-5 hours to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution; wherein, the solvent is xylene; the mass ratio of the mixed precursor to the solvent is (1-3):1; the molar ratio of the ZrC precursor powder, HfC precursor powder and TiC precursor is (5-10):(5-10):(1-5);

[0042] Step 4:

[0043] Step a, Impregnation-Drying:

[0044] The low-density C / C composite material was immersed in the mixed precursor solution obtained in step 3, and placed in a vacuum drying oven. The vacuum was drawn to -0.08 to -0.1 MPa and held for 20 to 30 minutes. The C / C composite material impregnated with the precursor was removed, and the excess solution on the surface of the material was removed. The material was then placed in an oven at a temperature of 60 to 80°C and dried. The impregnation-drying process was repeated 3 times to obtain the dried C / C composite material impregnated with the precursor.

[0045] Step b, High-temperature heat treatment:

[0046] The dried C / C composite material impregnated with the precursor obtained in step a is tightly wrapped with graphite paper and placed in the constant temperature zone of a high-temperature tube furnace. Using Ar as the protective gas, the temperature is raised to 1600-1900℃ at a rate of 3-5℃ / min and held for 1-3 hours. Then, the temperature is lowered to room temperature at a rate of 2-4℃ / min to achieve the introduction of ternary ceramics into the material.

[0047] The process involves repeated impregnation, drying, and high-temperature heat treatment 8 to 11 times to finally obtain the C / C-(Zr,Hf,Ti)C composite material.

[0048] Preferably, the density of the above-mentioned porous low-density C / C composite material is 1.0 to 1.3 g / cm³. 3 .

[0049] Preferably, the ZrC precursor:HfC precursor:TiC precursor = (5~10):(5~10):(1~5).

[0050] 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.

[0051] 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.

[0052] Example 1

[0053] A method for preparing a C / C-(Zr,Hf,Ti)C composite material includes the following steps:

[0054] Step 1: Place the clean carbon felt in a chemical vapor deposition furnace, using hydrocarbons as the carbon source and Ar as both the carrier and protective gas, and perform chemical vapor deposition. After the deposition is complete, cool the material with the furnace to obtain a material with a density of 1.0 g / cm³. 3 Porous low-density C / C composite materials;

[0055] Step 2: Clean the C / C composite material with anhydrous ethanol and dry it for 15 hours for later use.

[0056] Step 3: Preparation of ZrC-HfC-TiC ternary ceramic organic precursor solution:

[0057] Take 23.5g of ZrC precursor (PZC), 25.6.3g of HfC precursor (PHC), and 1.7g of TiC (C 16 H 36 The O4Ti) precursor was mixed and 20g of xylene was added as a solvent. The mixture was ultrasonically vibrated for 3h to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution.

[0058] Step 4: Introduction of ZrC-HfC-TiC ternary ceramic organic precursor solution into the C / C composite material:

[0059] Step a, Impregnation-Drying:

[0060] The porous low-density C / C composite material was immersed in the ZrC-HfC-TiC ternary ceramic organic precursor solution obtained in step 3, and placed in a vacuum drying oven. The vacuum was drawn to -0.1 MPa and held for 20 min. After removing the C / C composite material impregnated with the precursor, the excess solution on the surface of the material was removed, and the material was placed in an oven at 80℃ and dried for 15 h. The impregnation-drying process was repeated 3 times to obtain the dried C / C composite material impregnated with the precursor.

[0061] Step b, High-temperature heat treatment:

[0062] The dried C / C composite material impregnated with the precursor obtained in step a was tightly wrapped with graphite paper and placed in the constant temperature zone of a high-temperature tube furnace. Furnace plugs were installed on both sides of the furnace tube. Ar was used as the protective gas, and the temperature was raised to 1600℃ at a rate of 5℃ / min. After holding at this temperature for 1 hour, the temperature was lowered to room temperature at a rate of 3℃ / min to achieve the introduction of ternary ceramics into the material.

[0063] The C / C-(Zr,Hf,Ti)C composite material was obtained by repeating the impregnation-drying-high temperature heat treatment process nine times.

[0064] Example 2

[0065] A method for preparing a C / C-(Zr,Hf,Ti)C composite material includes the following steps:

[0066] Step 1: Place the clean carbon felt in a chemical vapor deposition furnace, using hydrocarbons as the carbon source and Ar as the carrier and protective gas, and perform chemical vapor deposition. After completion, cool with the furnace to obtain a density of 1.2 g / cm³. 3 Porous low-density C / C composite materials;

[0067] Step 2: Clean the C / C composite material with anhydrous ethanol and dry it for 15 hours for later use.

[0068] Step 3: Preparation of ZrC-HfC-TiC ternary ceramic organic precursor solution:

[0069] Take 15.9g of ZrC precursor (PZC), 35.4g of HfC precursor (PHC), and 8.5g of TiC (C 16 H 36 The O4Ti) precursor was mixed and 10g of xylene was added as a solvent. The mixture was ultrasonically vibrated for 5h to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution.

[0070] Step 4: Introduction of ZrC-HfC-TiC ternary ceramic organic precursor solution into the C / C composite material:

[0071] Step a, Impregnation-Drying:

[0072] The porous low-density C / C composite material was immersed in the ZrC-HfC-TiC ternary ceramic organic precursor solution obtained in step 3, and placed in a vacuum drying oven. The vacuum was drawn to -0.08 MPa and held for 25 min. After removing the C / C composite material impregnated with the precursor, the excess solution on the surface of the material was removed, and the material was placed in an oven at 80℃ and dried for 15 h. The impregnation-drying process was repeated 3 times to obtain the dried C / C composite material impregnated with the precursor.

[0073] Step b, High-temperature heat treatment:

[0074] The dried C / C composite material impregnated with the precursor obtained in step a was tightly wrapped with graphite paper and placed in the constant temperature zone of a high-temperature tube furnace. Furnace plugs were installed on both sides of the furnace tube. Ar was used as the protective gas, and the temperature was raised to 2100℃ at a rate of 5℃ / min. After holding at this temperature for 2 hours, the temperature was lowered to room temperature at a rate of 2℃ / min to achieve the introduction of ternary ceramics into the interior of the material.

[0075] The C / C-(Zr,Hf,Ti)C composite material was obtained by repeating the impregnation-drying-high temperature heat treatment process eight times.

[0076] Example 3

[0077] A method for preparing a C / C-(Zr,Hf,Ti)C composite material includes the following steps:

[0078] Step 1: Place the clean carbon felt in a chemical vapor deposition furnace, using hydrocarbons as the carbon source and Ar as the carrier and protective gas, and perform chemical vapor deposition. After the deposition is complete, cool with the furnace to obtain a density of 1.3 g / cm³. 3 Porous low-density C / C composite materials;

[0079] Step 2: Clean the C / C composite material with anhydrous ethanol and dry it for 15 hours for later use.

[0080] Step 3: Preparation of ZrC-HfC-TiC ternary ceramic organic precursor solution:

[0081] Take 21.6g of ZrC precursor (PZC), 30.3g of HfC precursor (PHC), and 5.1g of TiC (C 16 H 36 The O4Ti) precursor was mixed and 17.3g of xylene was added as a solvent. The mixture was ultrasonically vibrated for 4h to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution.

[0082] Step 4: Introduction of ZrC-HfC-TiC ternary ceramic organic precursor solution into the C / C composite material:

[0083] Step a, Impregnation-Drying:

[0084] The porous low-density C / C composite material was immersed in the ZrC-HfC-TiC ternary ceramic organic precursor solution obtained in step 3, and placed in a vacuum drying oven. The vacuum was drawn to -0.08 MPa and held for 20 min. After removing the C / C composite material impregnated with the precursor, the excess solution on the surface of the material was removed, and the material was placed in an oven at 80℃ and dried for 15 h. The impregnation-drying process was repeated 3 times to obtain the dried C / C composite material impregnated with the precursor.

[0085] Step b, High-temperature heat treatment:

[0086] The dried C / C composite material impregnated with the precursor obtained in step a was tightly wrapped with graphite paper and placed in the constant temperature zone of a high-temperature tube furnace. Furnace plugs were installed on both sides of the furnace tube. Ar was used as the protective gas, and the temperature was raised to 1900℃ at a rate of 4℃ / min. After holding at this temperature for 3 hours, the temperature was lowered to room temperature at a rate of 3℃ / min to achieve the introduction of ternary ceramics into the interior of the material.

[0087] The process involved repeated impregnation, drying, and high-temperature heat treatment 11 times to finally obtain the C / C-(Zr,Hf,Ti)C composite material.

[0088] Example 4

[0089] A method for preparing a C / C-(Zr,Hf,Ti)C composite material includes the following steps:

[0090] Step 1: Place the clean carbon felt in a chemical vapor deposition furnace, using hydrocarbons as the carbon source and Ar as the carrier and protective gas, and perform chemical vapor deposition. After the deposition is complete, cool with the furnace to obtain a density of 1.3 g / cm³. 3 Porous low-density C / C composite materials;

[0091] Step 2: Clean the C / C composite material with anhydrous ethanol and dry it for 15 hours for later use.

[0092] Step 3: Preparation of ZrC-HfC-TiC ternary ceramic organic precursor solution:

[0093] Take 21.6g of ZrC precursor (PZC), 30.3g of HfC precursor (PHC), and 5.1g of TiC (C 16 H 36 The O4Ti) precursor was mixed and 17.3g of xylene was added as a solvent. The mixture was ultrasonically vibrated for 4h to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution.

[0094] Step 4: Introduction of ZrC-HfC-TiC ternary ceramic organic precursor solution into the C / C composite material:

[0095] Step a, Impregnation-Drying:

[0096] The porous low-density C / C composite material was immersed in the ZrC-HfC-TiC ternary ceramic organic precursor solution obtained in step 3, and placed in a vacuum drying oven. The vacuum was drawn to -0.08 MPa and held for 30 min. After removing the C / C composite material impregnated with the precursor, the excess solution on the surface of the material was removed, and the material was placed in an oven at 80℃ and dried for 15 h. The impregnation-drying process was repeated 3 times to obtain the dried C / C composite material impregnated with the precursor.

[0097] Step b, High-temperature heat treatment:

[0098] The dried C / C composite material impregnated with the precursor obtained in step a was tightly wrapped with graphite paper and placed in the constant temperature zone of a high-temperature tube furnace. Furnace plugs were installed on both sides of the furnace tube. Ar was used as the protective gas, and the temperature was raised to 1900℃ at a rate of 4℃ / min. After holding at this temperature for 3 hours, the temperature was lowered to room temperature at a rate of 4℃ / min to achieve the introduction of ternary ceramics into the interior of the material.

[0099] The process involved repeated impregnation, drying, and high-temperature heat treatment 11 times to finally obtain the C / C-(Zr,Hf,Ti)C composite material.

[0100] Figure 1 The images show low-magnification TEM, EDS, and high-magnification TEM images of the ceramic block in the C / C-(Zr,Hf,Ti)C composite material. It can be seen from the images that the three elements Zr, Hf, and Ti are uniformly distributed and there is no obvious elemental segregation. The interplanar spacing of the ternary single-phase solid solution ceramic (Zr,Hf,Ti)C is 0.260 nm.

[0101] Figure 2The image shows the macroscopic morphology of the C / C-(Zr,Hf,Ti)C composite material. As can be seen from the image, the material is gray and has a relatively smooth surface.

[0102] Figure 3 The image shows the surface XRD pattern of the C / C-(Zr,Hf,Ti)C composite material. It can be seen from the image that the surface of the prepared material is mainly composed of single-phase solid solution ceramic (Zr,Hf,Ti)C.

[0103] Figure 4 The image shows the XRD pattern of the ablated surface of the C / C-(Zr,Hf,Ti)C composite material. It can be seen from the image that the oxidation products on the surface of the material after ablation are mainly (Zr,Hf,Ti)O2 and (Zr,Hf)O2.

[0104] Figure 5 The image shows the macroscopic and ablation center micromorphology of the C / C-(Zr,Hf,Ti)C composite material. As can be seen from the image, a relatively dense oxide layer was formed on the surface of the material after ablation, and no obvious oxide layer peeling was observed.

[0105] 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 C / C-(Zr,Hf,Ti)C composite material, characterized in that, Includes the following steps: S1: The porous low-density C / C composite material was immersed in a ZrC-HfC-TiC ternary ceramic organic precursor solution and then vacuum dried to obtain the C / C composite material impregnated with the precursor. S2: After drying the C / C composite material impregnated with the precursor, the dried C / C composite material impregnated with the precursor is obtained; S3: Repeat steps S1 and S2 several times in sequence, wrap the dried C / C composite material impregnated with the precursor with graphite paper, and then perform heat treatment in an inert atmosphere; S4: Repeat steps S1 to S3 several times to finally obtain the C / C-(Zr,Hf,Ti)C composite material; The preparation method of the ZrC-HfC-TiC ternary ceramic organic precursor solution is as follows: ZrC precursor powder, HfC precursor powder and TiC precursor are mixed to obtain a mixed precursor; the mixed precursor is mixed with a solvent to obtain a mixed precursor solution; the mixed precursor solution is subjected to ultrasonic vibration to obtain a ZrC-HfC-TiC ternary ceramic organic precursor solution. In S3, the number of times to repeat steps S1 and S2 is three; the process parameters for heat treatment under an inert atmosphere are: using an inert gas as a protective gas, heating to 1600~2100℃ at a rate of 3~5℃ / min, holding at that temperature for 1~3h, and then cooling to room temperature at a rate of 2~4℃ / min. In S4, the number of times the steps S1 to S3 are repeated is 8 to 11.

2. The method for preparing a C / C-(Zr,Hf,Ti)C composite material according to claim 1, characterized in that, The method for preparing the porous low-density C / C composite material is as follows: Carbon felt was subjected to chemical vapor deposition (CVD) with hydrocarbon gas as the carbon source and Ar as the carrier and protective gas. After CVD, it was cooled in the furnace to obtain a porous low-density C / C composite material.

3. The method for preparing a C / C-(Zr,Hf,Ti)C composite material according to claim 1, characterized in that, The mass ratio of the mixed precursor to the solvent is (1~3):1; the solvent is xylene; the molar ratio of the ZrC precursor powder, HfC precursor powder and TiC precursor is (5~10):(5~10):(1~5); The duration of the ultrasonic oscillation is 3-5 hours.

4. The method for preparing a C / C-(Zr,Hf,Ti)C composite material according to claim 1, characterized in that, In S1, the process parameters for the vacuum drying process are: evacuate to -0.08~-0.1MPa and hold for 20~30 minutes.

5. The method for preparing a C / C-(Zr,Hf,Ti)C composite material according to claim 1, characterized in that, In S2, the drying temperature is 60~80℃.

6. The method for preparing a C / C-(Zr,Hf,Ti)C composite material according to claim 1, characterized in that, The porous low-density C / C composite material has a density of 1.0~1.3 g / cm³. 3 .

7. A C / C-(Zr,Hf,Ti)C composite material, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 6.

Images