阅读说明：本技术 一种改性的c/c复合材料及其制备方法 (Modified C/C composite material and preparation method thereof ) 是由 陈飞雄 杨鑫 颜君毅 黄启忠 王铁军 于 2020-06-09 设计创作，主要内容包括：本发明提供了一种改性的C/C复合材料及其制备方法,制法包括：对炭纤维预制体进行界面改性,得到界面改性的C/C复合材料,改善复合材料中炭纤维与基体界面的结合性能以及保护炭纤维,从而提高C/C复合材料的高温抗氧化性能；进一步对界面改性的C/C复合材料进行基体改性,得到改性的C/C复合材料骨架,大大提高C/C复合材料基体碳的高温抗氧化与耐冲刷性能；并且,采用高温真空压力浸渗法将铜浸入改性的C/C复合材料骨架中,得到改性的C/C复合材料,利用铜的自发汗冷却和热冗作用,降低C/C复合材料烧蚀时的热量聚积程度和温升速度,从而提高C/C复合材料的耐烧蚀性能。(The invention provides a modified C/C composite material and a preparation method thereof, and the preparation method comprises the following steps: the carbon fiber preform is subjected to interface modification to obtain an interface-modified C/C composite material, and the bonding performance of the carbon fiber and a matrix interface in the composite material is improved, and the carbon fiber is protected, so that the high-temperature oxidation resistance of the C/C composite material is improved; the matrix modification is further carried out on the interface modified C/C composite material to obtain a modified C/C composite material framework, so that the high-temperature oxidation resistance and the scouring resistance of the matrix carbon of the C/C composite material are greatly improved; and the copper is immersed into the modified C/C composite material framework by adopting a high-temperature vacuum pressure infiltration method to obtain the modified C/C composite material, and the spontaneous perspiration cooling and heat redundancy effect of the copper are utilized to reduce the heat accumulation degree and the temperature rise speed of the C/C composite material during ablation, so that the ablation resistance of the C/C composite material is improved.)

1. A preparation method of a modified C/C composite material is characterized by comprising the following steps:

carrying out interface modification on the carbon fiber preform to obtain an interface modified C/C composite material;

and carrying out matrix modification on the interface-modified C/C composite material to obtain a modified C/C composite material skeleton.

2. The preparation method of the modified C/C composite material according to claim 1, wherein the interface modification is performed on the carbon fiber preform to obtain the interface-modified C/C composite material, and specifically comprises the following steps:

and depositing an interface coating on the surface of the carbon fiber in the carbon fiber preform by adopting a chemical vapor infiltration method to obtain the carbon fiber preform with the modified interface.

3. The method for preparing the modified C/C composite material according to claim 2, wherein the interface coating is a silicon carbide interface coating, the silicon carbide interface coating is deposited by using trichloromethylsilane as a precursor, hydrogen as a carrier gas, argon as a diluent gas, 1100-1300 ℃ as a deposition temperature and 0.5-1.0KPa as a deposition pressure.

4. The method for preparing the modified C/C composite material according to claim 2, wherein the interface coating is a pyrolytic carbon/silicon carbide composite interface coating, and the deposition process is as follows:

firstly, depositing a pyrolytic carbon interface coating on the surface of carbon fibers in the carbon fiber preform to obtain a first interface modified carbon fiber preform, wherein in the deposition process of the pyrolytic carbon interface coating, the reaction gas adopts natural gas, the dilution gas adopts nitrogen, the deposition temperature is 900-1100 ℃, and the deposition pressure is 1-3 KPa;

and depositing a silicon carbide interface coating on the surface of the carbon fiber in the first interface modified carbon fiber preform to obtain the interface modified carbon fiber preform, wherein the precursor of the silicon carbide interface coating is trichloromethylsilane, the carrier gas is hydrogen, the diluent gas is argon, the deposition temperature is 1100-1300 ℃, and the deposition pressure is 0.5-1.0KPa in the deposition process.

5. The preparation method of the modified C/C composite material according to any one of claims 3 to 4, wherein the interface-modified carbon fiber preform is densified to obtain the interface-modified C/C composite material, and the method specifically comprises the following steps: and depositing a pyrolytic carbon matrix on the interface modified carbon fiber preform by adopting a chemical vapor infiltration method to obtain the interface modified C/C composite material, wherein the used carbon source gas is natural gas, the diluent gas is nitrogen, the deposition temperature is 1150 ℃, and the deposition time is 150-300 h.

6. The method for preparing the modified C/C composite material according to claim 1, wherein the matrix modification is performed on the interface-modified C/C composite material to obtain the modified C/C composite material skeleton, and the method comprises the following steps:

adding SiC ceramic and ZrC ceramic into the interface modified C/C composite material by adopting a precursor impregnation-pyrolysis method, and carrying out matrix modification on the interface modified C/C composite material to obtain a modified C/C composite material skeleton, wherein the method comprises the following steps:

obtaining a mixed precursor containing polycarbosilane and a Zr-containing organic polymer;

carrying out dipping treatment on the interface modified C/C composite material through the mixed precursor to obtain a dipped body;

carrying out cross-linking curing treatment on the impregnated body to obtain a cured body;

and cracking the solidified body to obtain the modified C/C composite material skeleton.

7. The method for preparing the modified C/C composite material according to claim 6, wherein the polycarbosilane and the Zr-containing organic polymer are co-dissolved to obtain the mixed precursor, wherein the mass ratio of the polycarbosilane to the Zr-containing organic polymer is 1: 4-9.

8. The method for preparing the modified C/C composite material as claimed in claim 6, wherein the dipping time is 0.5-1.5h and the dipping pressure is 1.2-1.5MPa in the dipping treatment process.

9. The method as claimed in claim 6, wherein the curing temperature is 120-300 ℃ and the curing time is 1-2 h.

10. The method as claimed in claim 6, wherein the cracking temperature is 1500-1700 ℃, and the cracking time is 1-3 h.

11. The method as claimed in claim 2, wherein the modified C/C composite material is obtained by performing copper leaching on the modified C/C composite material skeleton by high-temperature vacuum pressure infiltration, wherein during the copper leaching, the copper leaching temperature is controlled to be 1300-1400 ℃, the copper leaching pressure is 10-15MPa, and the copper leaching time is 0.5-1.5 h.

12. A modified C/C composite material, characterized in that it is prepared by the process for the preparation of a modified C/C composite material according to any one of claims 1 to 11.

Technical Field

The invention belongs to the field of ablation type thermal protection materials, and particularly relates to a modified C/C composite material and a preparation method thereof.

Background

The ablative thermal protection material is an important engineering material in the fields of national defense and aerospace aviation, is mainly used as an engineering material of an aircraft, can be decomposed, melted, evaporated, sublimated and other heat-absorbing physical and chemical changes through the material in the working time of the aircraft, particularly under the conditions of high temperature and high-speed airflow scouring, takes away a large amount of heat by virtue of the mass consumption of the material, thereby preventing the heat from being transmitted to the internal structure of the material, and maintaining the pneumatic appearance to ensure that the aircraft normally works. With the improvement of flight speed of an aircraft and the requirement of higher reliability and higher service performance, ablative thermal protection materials with low density, ultrahigh temperature resistance, ablation resistance and even zero ablation have become research hotspots.

The high-temperature resistant materials which can be used as ablative thermal protection materials at present mainly comprise tungsten copper infiltrated materials, graphite materials, C/C composite materials and ultrahigh-temperature ceramics (the English abbreviation is UHTCs, and mainly refers to refractory metal carbides and borides, such as HfC and HfB₂Etc.). Wherein, the density of the tungsten copper infiltration material is high; the graphite material has poor strength, high ablation rate and poor thermal shock resistance; the ultrahigh-temperature ceramic has low fracture toughness and poor thermal shock resistance. Therefore, the ablative thermal protective materials described above have limitations in practical applications. The existing C/C composite material is light in weight, resistant to high temperature and thermal shock and is an ideal high-temperature heat-resistant material in an inert environment, but the interface activity of carbon fibers and matrix carbon in the C/C composite material is large, stress is concentrated, so that the high-temperature oxidation resistance and ablation resistance of the C/C composite material are poor, and the fluid scouring resistance of the C/C composite material is poor.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a preparation method of a modified C/C composite material, which solves the technical problems that the high-temperature oxidation resistance and ablation resistance of the existing C/C composite material are poor, and the fluid scouring resistance of the C/C composite material is poor.

The invention is realized by the following technical scheme:

the invention discloses a preparation method of a modified C/C composite material, which comprises the following steps:

carrying out interface modification on the carbon fiber preform to obtain an interface modified C/C composite material;

and carrying out matrix modification on the interface modified C/C composite material to obtain a modified C/C composite material skeleton.

Further, the interface modification is performed on the carbon fiber preform to obtain the interface modified C/C composite material, which specifically comprises:

and depositing an interface coating on the surface of the carbon fiber in the carbon fiber preform by adopting a chemical vapor infiltration method to obtain the carbon fiber preform with the modified interface.

Further, the interface coating is a silicon carbide interface coating, during the deposition process of the silicon carbide interface coating, the precursor is trichloromethylsilane, the carrier gas is hydrogen, the diluent gas is argon, the deposition temperature is 1100-1300 ℃, and the deposition pressure is 0.5-1.0 KPa.

Further, the interface coating is a pyrolytic carbon/silicon carbide composite interface coating, and the deposition process is as follows:

firstly, depositing a pyrolytic carbon interface coating on the surface of carbon fibers in a carbon fiber preform to obtain a first interface modified carbon fiber preform, wherein in the deposition process of the pyrolytic carbon interface coating, the reaction gas adopts natural gas, the dilution gas adopts nitrogen, the deposition temperature is 900-1100 ℃, and the deposition pressure is 1-3 KPa;

and depositing a silicon carbide interface coating on the surface of the carbon fiber in the first interface modified carbon fiber preform to obtain the interface modified carbon fiber preform, wherein the silicon carbide interface coating is deposited by using trichloromethylsilane as a precursor, hydrogen as a carrier gas, argon as a diluent gas, the deposition temperature is 1100-1300 ℃, and the deposition pressure is 0.5-1.0 KPa.

Further, the interface-modified carbon fiber preform is densified to obtain an interface-modified C/C composite material, which specifically includes: and depositing a pyrolytic carbon matrix on the interface-modified carbon fiber preform by adopting a chemical vapor infiltration method to obtain the interface-modified C/C composite material, wherein the used carbon source gas is natural gas, the diluent gas is nitrogen, the deposition temperature is 1150 ℃, and the deposition time is 150-300 h.

Further, the matrix modification of the interface-modified C/C composite material to obtain a modified C/C composite material skeleton includes:

adding SiC ceramic and ZrC ceramic into the interface modified C/C composite material by adopting a precursor impregnation-pyrolysis method, and carrying out matrix modification on the interface modified C/C composite material to obtain a modified C/C composite material skeleton, wherein the method comprises the following steps:

obtaining a mixed precursor containing polycarbosilane and a Zr-containing organic polymer;

carrying out dipping treatment on the interface modified C/C composite material through the mixed precursor to obtain a dipped body;

carrying out cross-linking curing treatment on the impregnated body to obtain a cured body;

and cracking the solidified body to obtain the modified C/C composite material skeleton.

Further, polycarbosilane and the organic polymer containing Zr are co-dissolved to obtain the mixed precursor, wherein the mass ratio of the polycarbosilane to the organic polymer containing Zr is 1: 4-9.

Furthermore, in the dipping treatment process, the dipping time is 0.5-1.5h, and the dipping pressure is 1.2-1.5 MPa.

Furthermore, in the cross-linking curing process, the curing temperature is 120-300 ℃, and the curing time is 1-2 h.

Furthermore, in the cracking treatment process, the cracking temperature is 1500-1700 ℃, and the cracking time is 1-3 h.

Further, carrying out copper leaching operation on the modified C/C composite material skeleton by adopting a high-temperature vacuum pressure infiltration method to obtain the modified C/C composite material, wherein in the copper leaching operation process, the copper leaching temperature is controlled to be 1300-1400 ℃, the copper leaching pressure is 10-15MPa, and the copper leaching time is 0.5-1.5 h.

The invention also provides a modified C/C composite material, which is prepared by adopting the preparation method of the modified C/C composite material.

Compared with the closest prior art, the technical scheme of the invention has the following beneficial effects:

the invention provides a preparation method of a modified C/C composite material, which comprises the steps of carrying out interface modification on a carbon fiber preform to obtain an interface-modified C/C composite material, preferably depositing a silicon carbide (SiC) interface coating or a pyrolytic carbon (PyC)/silicon carbide (SiC) composite interface coating on the surface of carbon fibers in the carbon fiber preform by adopting a Chemical Vapor Infiltration (CVI) method to obtain the interface-modified carbon fiber preform, and carrying out densification treatment on the interface-modified carbon fiber preform to obtain the interface-modified C/C composite material, wherein compared with the existing C/C composite material, the bonding property of the carbon fibers and a matrix interface in the composite material is improved, the carbon fibers are protected, and the high-temperature oxidation resistance of the C/C composite material is improved; the matrix of the interface modified C/C composite material is further modified to obtain a modified C/C composite material skeleton, SiC ceramic and ZrC ceramic are preferably added into the interface modified C/C composite material by a precursor impregnation-pyrolysis process (PIP) to modify the matrix of the C/C composite material, so that the high-temperature oxidation resistance and scouring resistance of the matrix carbon of the C/C composite material are greatly improved; in addition, according to the preparation method, the copper is immersed into the modified C/C composite material framework by adopting a high-temperature vacuum pressure infiltration method, and the spontaneous perspiration cooling and heat redundancy effects of the copper are utilized to reduce the heat accumulation degree and the temperature rise speed of the C/C composite material during ablation, so that the ablation resistance of the C/C composite material is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a process flow diagram of a method of preparing a modified C/C composite of examples 1-3 of the present invention;

FIG. 2 is a topographical view of a modified C/C composite material obtained in example 1 using the method of the present invention for preparing a modified C/C composite material.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

As shown in fig. 1, the preparation method of the modified C/C composite material provided in this embodiment includes the following steps:

s1: obtaining a carbon fiber preform: the carbon fiber preform adopts the existing carbon fiber preform with a needle-punched integral felt structure, and the density of the preform is preferably 0.4g/cm³。

S2: depositing an interface coating on the surface of the carbon fiber to obtain an interface modified carbon fiber preform: specifically, a Chemical Vapor Infiltration (CVI) method is adopted to deposit a pyrolytic carbon (PyC)/silicon carbide (SiC) composite interface coating on the surface of carbon fibers in a carbon fiber preform to obtain an interface modified carbon fiber preform, and the process is as follows:

firstly, depositing a pyrolytic carbon interface coating on the surface of carbon fiber to obtain a first interface modified carbon fiber preform, wherein in the deposition process of the pyrolytic carbon interface coating, the reaction gas adopts natural gas, the diluent gas adopts nitrogen, the deposition temperature is 1000 ℃, and the deposition pressure is 2 KPa;

and depositing a silicon carbide interface coating on the surface of the carbon fiber of the first interface modified carbon fiber preform to obtain the interface modified carbon fiber preform, wherein the precursor of the silicon carbide interface coating is trichloromethylsilane, the carrier gas is hydrogen, the diluent gas is argon, the deposition temperature is 1100 ℃, and the deposition pressure is 0.5KPa in the deposition process.

The total thickness of the pyrolytic carbon (PyC)/silicon carbide (SiC) composite coating is not more than 1 μm, and preferably, the thickness of the pyrolytic carbon (PyC) coating is 0.3 μm, and the thickness of the silicon carbide (SiC) coating is 0.7 μm.

The Chemical Vapor Infiltration (CVI) method described above may be performed by conventional processes, and those skilled in the art may adjust only some of the reaction media and process parameters according to actual needs.

S3: densifying, namely densifying the interface-modified carbon fiber preform to obtain the interface-modified C/C composite material, wherein the densifying treatment mode of the interface-modified carbon fiber preform is to deposit a pyrolytic carbon (PyC) matrix in the interface-modified carbon fiber preform by adopting a Chemical Vapor Infiltration (CVI) method, the used carbon source gas is natural gas, the diluent gas is nitrogen, the deposition temperature is 950 ℃, and the deposition time is 150 hours, so that the density of the interface-modified C/C composite material is increased to 1.0g/cm³；

The Chemical Vapor Infiltration (CVI) method described above may be performed by conventional processes, and those skilled in the art may adjust only some of the reaction media and process parameters according to actual needs.

S4: matrix modification, namely adding SiC ceramic and ZrC ceramic into the interface modified C/C composite material by adopting a precursor impregnation-pyrolysis process (PIP) to carry out matrix modification to obtain a modified C/C composite material skeleton, and specifically comprising the following steps:

obtaining a mixed precursor containing polycarbosilane and a Zr-containing organic polymer, specifically co-dissolving the polycarbosilane and the Zr-containing organic polymer to obtain the mixed precursor, wherein the mass ratio of the polycarbosilane to the Zr-containing organic polymer is 1:4, and the Zr-containing organic polymer can adopt polycarbozirane;

carrying out impregnation treatment on the interface modified C/C composite material through the mixed precursor, wherein the impregnation time is 0.5h, and the impregnation pressure is 1.2MPa, so as to obtain an impregnated body;

carrying out cross-linking curing treatment on the impregnated body, wherein the curing temperature is 120 ℃, and the curing time is 1h, so as to obtain a cured body;

cracking the solidified body at 1500 ℃ for 1h to obtain a modified C/C composite material skeleton;

the above step S4 may be repeatedly performed a plurality of times until a density of 2.25g/cm is obtained³The modified C/C composite backbone of (a);

the precursor impregnation-pyrolysis (PIP) method can be performed by the conventional process, and a person skilled in the art can adjust only some reaction media and process parameters according to actual needs.

S5: and (3) high-temperature vacuum pressure copper leaching, namely performing copper leaching operation on the modified C/C composite material framework by adopting a high-temperature vacuum pressure copper leaching method to obtain the modified C/C composite material, wherein in the copper leaching operation process, the copper leaching temperature is controlled to be 1300 ℃, the copper leaching pressure is 10MPa, and the copper leaching time is 0.5 h.

The embodiment also provides a modified C/C composite material, which is prepared by the preparation method of the modified C/C composite material, and the density of the modified C/C composite material is 3.80g/cm³The volume fraction of (SiC + ZrC) is 25%, and the volume fraction of Cu is 18%.

Fig. 2 is a structural morphology diagram of the modified C/C composite material prepared in this example, which includes carbon fibers, a pyrolytic carbon (PyC) interface coating and a silicon carbide (SiC) interface coating on the surface of the carbon fibers, a pyrolytic carbon (PyC) matrix, SiC and ZrC ceramics added for matrix modification, and immersed Cu.

The modified C/C composite material prepared in this example was subjected to an ablation test using plasma flame in an atmospheric environment. The unmodified C/C composite was also subjected to ablation testing under the same ablation testing conditions. The average linear etch rate of the material was tested and the results are shown in table 1 below.

TABLE 1

It can be seen that the modified C/C composite prepared in this example had an average line ablation rate of 0.8 μm/s, which was reduced by 62% compared to the unmodified C/C composite having an average line ablation rate of 2.1 μm/s.

Example 2

As shown in fig. 1, the preparation method of the modified C/C composite material provided in this embodiment includes the following steps:

s1: obtaining a carbon fiber preform: the carbon fiber preform adopts the existing preform with a fine weaving and puncturing structure, and the density of the preform is preferably 0.6g/cm³。

S2: depositing an interface coating on the surface of the carbon fiber to obtain an interface modified carbon fiber preform: specifically, a Chemical Vapor Infiltration (CVI) method is adopted to deposit a silicon carbide (SiC) interface coating on the surface of carbon fibers in a carbon fiber preform to obtain the carbon fiber preform with modified interface, the precursor is trichloromethylsilane, the carrier gas is hydrogen, the diluent gas is argon, the deposition temperature is 1300 ℃, and the deposition pressure is 1.0 KPa. The silicon carbide coating thickness is preferably 0.5 μm.

The Chemical Vapor Infiltration (CVI) method described above may be performed by conventional processes, and those skilled in the art may adjust only some of the reaction media and process parameters according to actual needs.

S3: densifying, namely densifying the interface-modified carbon fiber preform to obtain the interface-modified C/C composite material, wherein the densifying treatment mode of the interface-modified carbon fiber preform is to deposit a pyrolytic carbon (PyC) matrix in the interface-modified carbon fiber preform by adopting a Chemical Vapor Infiltration (CVI) method, the used carbon source gas is natural gas, the diluent gas is nitrogen, the deposition temperature is 1150 ℃, the deposition time is 300 hours, and the density of the interface-modified C/C composite material is increased to 1.2g/cm³；

The Chemical Vapor Infiltration (CVI) method described above may be performed by conventional processes, and those skilled in the art may adjust only some of the reaction media and process parameters according to actual needs.

S4: matrix modification, namely adding SiC ceramic and ZrC ceramic into the interface modified C/C composite material by adopting a precursor impregnation-pyrolysis process (PIP) to carry out matrix modification to obtain a modified C/C composite material skeleton, and specifically comprising the following steps:

obtaining a mixed precursor containing polycarbosilane and a Zr-containing organic polymer, specifically co-dissolving the polycarbosilane and the Zr-containing organic polymer to obtain the mixed precursor, wherein the mass ratio of the polycarbosilane to the Zr-containing organic polymer is 1:6, and the Zr-containing organic polymer can adopt polycarbozirane;

carrying out impregnation treatment on the interface modified C/C composite material through the mixed precursor, wherein the impregnation time is 1.5h, and the impregnation pressure is 1.5MPa, so as to obtain an impregnated body;

carrying out cross-linking curing treatment on the impregnated body, wherein the curing temperature is 300 ℃, and the curing time is 2 hours, so as to obtain a cured body;

cracking the solidified body at 1700 ℃ for 3h to obtain a modified C/C composite material skeleton;

the above step S4 may be repeatedly performed a plurality of times until a density of 2.05g/cm is obtained³The modified C/C composite backbone of (a);

the precursor impregnation-pyrolysis (PIP) method can be performed by the conventional process, and a person skilled in the art can adjust only some reaction media and process parameters according to actual needs.

S5: and (3) high-temperature vacuum pressure copper leaching, namely performing copper leaching operation on the modified C/C composite material framework by adopting a high-temperature vacuum pressure copper leaching method to obtain the modified C/C composite material, wherein in the copper leaching operation process, the copper leaching temperature is controlled to be 1400 ℃, the copper leaching pressure is 15MPa, and the copper leaching time is 1.5 h.

The embodiment also provides a modified C/C composite material prepared by the preparation method of the modified C/C composite material, and the density of the modified C/C composite material is 3.20g/cm³The volume fraction of (SiC + ZrC) was 17%, and the volume fraction of Cu was 14%.

Example 3

As shown in fig. 1, the preparation method of the modified C/C composite material provided in this embodiment includes the following steps:

s1: obtaining a carbon fiber preform: the carbon fiber preform adopts the existing carbon fiber preform with a three-dimensional weaving structure, and the density of the preform is preferably 0.8g/cm³。

S2: depositing an interface coating on the surface of the carbon fiber to obtain an interface modified carbon fiber preform: specifically, a Chemical Vapor Infiltration (CVI) method is adopted to deposit a silicon carbide (SiC) interface coating on the surface of carbon fibers in a carbon fiber preform, the precursor is trichloromethyl silane, the carrier gas is hydrogen, the diluent gas is argon, the deposition temperature is 1200 ℃, and the deposition pressure is 0.8 KPa. The silicon carbide (SiC) coating thickness is preferably 1 μm.

The Chemical Vapor Infiltration (CVI) method described above may be performed by conventional processes, and those skilled in the art may adjust only some of the reaction media and process parameters according to actual needs.

S3: densifying, namely densifying the interface-modified carbon fiber preform to obtain the interface-modified C/C composite material, wherein the densifying treatment mode of the interface-modified carbon fiber preform is to deposit a pyrolytic carbon (PyC) matrix in the interface-modified carbon fiber preform by adopting a Chemical Vapor Infiltration (CVI) method, the used carbon source gas is natural gas, the diluent gas is nitrogen, the deposition temperature is 1050 ℃, the deposition time is 270h, and the density of the interface-modified C/C composite material is increased to 1.4g/cm³；

The Chemical Vapor Infiltration (CVI) method described above may be performed by conventional processes, and those skilled in the art may adjust only some of the reaction media and process parameters according to actual needs.

S4: matrix modification, namely adding SiC ceramic and ZrC ceramic into the interface modified C/C composite material by adopting a precursor impregnation-pyrolysis process (PIP) to carry out matrix modification to obtain a modified C/C composite material skeleton, and specifically comprising the following steps:

obtaining a mixed precursor containing polycarbosilane and a Zr-containing organic polymer, specifically co-dissolving the polycarbosilane and the Zr-containing organic polymer to obtain the mixed precursor, wherein the mass ratio of the polycarbosilane to the Zr-containing organic polymer is 1:9, and the Zr-containing organic polymer can adopt polycarbozirane;

carrying out impregnation treatment on the interface modified C/C composite material through the mixed precursor, wherein the impregnation time is 1.0h, and the impregnation pressure is 1.0MPa, so as to obtain an impregnated body;

carrying out cross-linking curing treatment on the impregnated body, wherein the curing temperature is 200 ℃, and the curing time is 1.5h, so as to obtain a cured body;

cracking the solidified body at 1600 ℃ for 2h to obtain a modified C/C composite material framework;

the above step S4 may be repeatedly performed a plurality of times until a density of 1.85g/cm is obtained³The modified C/C composite backbone of (a);

the precursor impregnation-pyrolysis (PIP) method can be performed by the conventional process, and a person skilled in the art can adjust only some reaction media and process parameters according to actual needs.

S5: high-temperature vacuum pressure copper leaching: and carrying out copper leaching operation on the modified C/C composite material framework by adopting a high-temperature vacuum pressure infiltration method to obtain the modified C/C composite material, wherein in the copper leaching operation process, the copper leaching temperature is controlled to be 1350 ℃, the copper leaching pressure is controlled to be 13MPa, and the infiltration time is 1.0 h.

The embodiment also provides a modified C/C composite material prepared by the preparation method of the modified C/C composite material, and the density of the modified C/C composite material is 2.60g/cm³The volume fraction of (SiC + ZrC) was 9%, and the volume fraction of Cu was 9%.

Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can make modifications and equivalents to the embodiments of the present invention without departing from the spirit and scope of the present invention, which is set forth in the claims of the present application.