Preparation method of ultrahigh-temperature modified C / SiC skin and ultrahigh-temperature modified C / SiC skin

Abstract

The invention discloses a preparation method of an ultra-high-temperature modified C / SiC skin and the ultra-high-temperature modified C / SiC skin, and solves the problems that an existing skin preparation method is high in cost and long in period, and the prepared skin is poor in density uniformity, ablation resistance and mechanical property. Step 2, performing interface deposition on the surface of the preform, and then performing high-temperature graphitization treatment to obtain a flat plate with a pyrolytic carbon interface; 3, chemical vapor deposition is conducted on the flat plate with the pyrolytic carbon interface, so that a SiC substrate is formed in the flat plate; 4, the flat plate with the SiC substrate is subjected to ultra-high-temperature particle slurry dipping, and ultra-high-temperature particles are contained in the flat plate; step 5, performing resin impregnation on the flat plate containing the ultra-high-temperature particles inside, and then performing curing and cracking in sequence to enable the flat plate to contain resin carbon inside; and step 6, carrying out reactive melt infiltration treatment on the flat plate containing the resin carbon inside to obtain the ultrahigh-temperature modified C / SiC skin.

Description

Technical Field

[0001] The present invention relates to a method for preparing a skin, and in particular to a method for preparing an ultra-high temperature modified C / SiC skin and the ultra-high temperature modified C / SiC skin. Background Art

[0002] Advanced aircraft are developing towards high speed (Ma>6), long flight time (more than 2000s), and full-range flight. This puts forward more stringent performance requirements for hot end components, and higher requirements for maneuverability. They are required not only to have certain comprehensive mechanical properties, but also to meet the lightweight characteristics of the structure. However, traditional single-element structural materials have gradually failed to meet the future service requirements of advanced aircraft. Actively developing lightweight, high-strength, high-toughness, and high-damage-tolerance hot end component materials is crucial to the design and research of aircraft.

[0003] The main function of aircraft rudder products is to change the flight trajectory and attitude of the aircraft by adjusting the angle of the rudder surface, thereby ensuring the stability and maneuverability of the aircraft. However, the preparation and application technology of lightweight, high-temperature resistant, and high-strength skin materials is one of the bottleneck technologies that restrict the round-trip flight capabilities of aircraft. Existing ceramic-based composite skins mainly use processes such as chemical vapor deposition and hot pressing. Chemical vapor deposition involves strict process parameter control, and the process testing and optimization process is time-consuming and labor-intensive. The mold manufacturing of compression molding and autoclave molding is complex and costly, and the density uniformity, ablation resistance, and mechanical properties of the prepared skin are poor. Therefore, conducting material configuration design, preparation, and performance research on rudder skins to obtain the structural parameters of preform units is the key to obtaining low-cost, short-cycle, large-size C / SiC ultra-high temperature modified rudder skin ceramic-based composite materials. Summary of the Invention

[0004] In order to solve the technical problems of high cost and long cycle in the existing skin preparation method and poor density uniformity, ablation resistance and mechanical properties of the prepared skin, the present invention provides a preparation method of ultra-high temperature modified C / SiC skin and an ultra-high temperature modified C / SiC skin.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing an ultra-high temperature modified C / SiC skin is characterized in that it comprises the following steps:

[0007] Step 1: Prepare the prefabricated body;

[0008] Step 2: performing interface deposition on the surface of the preform, and then performing high-temperature graphitization treatment to obtain a flat plate with a pyrolytic carbon interface;

[0009] Step 3: chemical vapor deposition is performed on the plate with the pyrolytic carbon interface to form a SiC matrix inside the plate;

[0010] Step 4: Impregnate the flat plate with the SiC substrate with the ultrahigh temperature particle slurry so that the flat plate contains ultrahigh temperature particles;

[0011] Step 5: impregnate the plate containing the ultra-high temperature particles with resin, and then solidify and crack it in sequence to make it contain resin carbon;

[0012] Step 6: Perform reactive melt infiltration treatment on the flat plate containing resin carbon to obtain an ultra-high temperature modified C / SiC skin.

[0013] Furthermore, step 2 specifically includes shaping the preform using a shaping mold, performing interface deposition on the surface of the preform after shaping, and then performing high-temperature graphitization treatment to obtain a flat plate with a pyrolytic carbon interface;

[0014] Step 3 specifically includes removing the shaping mold and performing chemical vapor deposition on the flat plate with the pyrolytic carbon interface to form a SiC matrix inside the flat plate.

[0015] Furthermore, step 2 specifically includes:

[0016] 2.1. Use the shaping mold to shape the preform;

[0017] 2.2. Deposition the preform after shaping at an interface with a propylene flow rate of 0.1 L / min to 20 L / min and an argon flow rate of 0.5 L / min to 21 L / min for 10 to 80 hours at a deposition temperature of 400° C. to 1100° C. for 2 to 8 heats.

[0018] 2.3. The preform after interface deposition is subjected to high-temperature graphitization treatment at a temperature of 1500°C to 2500°C for 0.5h to 15h. After cooling in the furnace, a flat plate with a pyrolytic carbon interface is obtained.

[0019] Furthermore, step 3 specifically includes:

[0020] 3.1. Remove the shaping mold;

[0021] 3.2. Chemical vapor deposition is performed on the flat plate having a pyrolytic carbon interface at a gas flow rate of 1 L / min to 15 L / min of trichloromethylsilane, 1 L / min to 15 L / min of argon, and 1 L / min to 15 L / min of hydrogen. The deposition temperature is 500°C to 1200°C, and the deposition time is 20 h to 100 h to form a SiC matrix inside the flat plate.

[0022] Furthermore, step 4 specifically includes:

[0023] 4.1. Place the flat plate with the SiC substrate in an impregnation tank filled with ultrahigh temperature particle slurry and suspend it above the ultrahigh temperature particle slurry. Vacuum the impregnation tank for 10 to 45 minutes.

[0024] 4.2. Immerse the flat plate in the ultra-high temperature particle slurry and vacuum impregnate for 10 to 45 minutes;

[0025] 4.3. Pressurize the inside of the impregnation tank to 0.2MPa~1.5MPa and immerse for 10min~45min;

[0026] 4.4. The impregnated flat plate is transferred to a drying oven for drying at a temperature of 30°C to 200°C to obtain a flat plate containing ultra-high temperature particles.

[0027] Furthermore, step 5 specifically includes:

[0028] 5.1. Place the flat plate containing the ultra-high temperature particles in an impregnation tank filled with resin and suspend it above the resin. Vacuum the tank for 10 to 45 minutes.

[0029] 5.2. Immerse the plate in the resin and vacuum impregnate for 10 to 45 minutes;

[0030] 5.3. Pressurize the inside of the impregnation tank to 0.2MPa~1.5MPa and immerse for 10min~45min;

[0031] 5.4. Place the impregnated plate in a drying oven at 30°C to 200°C for slow curing, with a curing time of 2h to 20h.

[0032] 5.5. The solidified flat plate is transferred to a cracking furnace for cracking at a cracking temperature of 600°C to 1500°C for 0.5h to 5h to obtain a flat plate containing resin carbon.

[0033] Furthermore, in step 4, the ultrahigh temperature particle slurry includes ZrB2, HfB2, ZrC, HfC and / or SiC.

[0034] Furthermore, in step 5.1, the resin is a phenolic resin.

[0035] Furthermore, step 1 is specifically as follows:

[0036] The preform is woven with C fiber yarn, with 5 to 24 warp layers, 3 to 23 weft layers, 2 to 22 warp yarns / cm, 1 to 15 weft yarns / cm and a thickness of 2 mm to 10 mm.

[0037] An ultra-high temperature modified C / SiC skin, which is special in that:

[0038] It is prepared by the above-mentioned method for preparing the ultra-high temperature modified C / SiC skin.

[0039] Beneficial effects of the present invention:

[0040] 1. The present invention provides a method for preparing an ultra-high temperature modified C / SiC skin. The method prepares a preform and combines ultra-high temperature particle slurry impregnation, resin impregnation and reactive melt infiltration treatment processes. This method reduces the production cost of the C / SiC skin. The ultra-high temperature modified C / SiC skin can be obtained in 1 to 1.5 months. The modified skin has good density uniformity, ablation resistance and mechanical properties, which is conducive to engineering applications.

[0041] 2. The present invention provides a method for preparing an ultra-high temperature modified C / SiC skin. The preform weaving step and the slurry impregnation step can control the division of the internal pore structure of the C / SiC skin, so that the ultra-high temperature particles are more evenly distributed in the C / SiC skin of the composite material, thereby improving the density of the C / SiC skin.

[0042] 3. The present invention provides a method for preparing an ultra-high temperature modified C / SiC skin, which can weave meter-sized C fiber preforms to form large-sized C / SiC skins. This method not only simplifies the shaping steps but also has good universality and meets more practical needs.

[0043] 4. The present invention provides a method for preparing an ultra-high temperature modified C / SiC skin, which can select different preparation processes and combine them according to the needs of the actual service environment to achieve the best match between its ablation performance and mechanical properties.

[0044] 5. The present invention provides a method for preparing an ultra-high temperature modified C / SiC skin, wherein the preform preparation parameters are more conducive to the subsequent ultra-high temperature particle slurry impregnation and resin impregnation processes, thereby improving the process adaptability of the C / SiC skin. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 : is a microscopic morphology of the ultrahigh temperature modified C / SiC skin prepared in Example 1 of the present invention, wherein a is the microscopic morphology of the cross section of the ultrahigh temperature modified C / SiC skin; b and c are the microscopic morphologies of the areas between and within the fiber bundles, respectively; d is an enlarged view of a local area of c;

[0046] Figure 2Figure 1 is a microscopic morphology of the ultra-high temperature modified C / SiC skin prepared in Example 2 of the present invention, wherein a is a microscopic morphology of a portion of the cross section of the C / SiC skin; b, c, and d are microscopic morphologies between fiber bundles in the cross section of the C / SiC skin, respectively;

[0047] Figure 3 This is a micromorphology of the ultra-high temperature modified C / SiC skin prepared in Example 3 of the present invention, where a is a micromorphology of a partial area of the C / SiC skin cross section; b, c, and d are micromorphologies between fiber bundles in the C / SiC skin cross section, respectively. DETAILED DESCRIPTION

[0048] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the accompanying drawings and embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0049] An embodiment of the present invention provides a method for preparing an ultra-high temperature modified C / SiC skin, comprising the following steps:

[0050] Step 1: Use C fiber yarn to weave a preform. The optimal weaving parameters of the preform are: 5 to 24 layers of warp yarn, 3 to 23 layers of weft yarn, warp density 2 to 22 yarns / cm, weft density 1 to 15 yarns / cm, and thickness 2 mm to 10 mm.

[0051] Step 2: performing interface deposition on the C fiber surface of the preform, and then performing high-temperature graphitization treatment to obtain a flat plate with a pyrolytic carbon interface; specifically comprising:

[0052] 2.1. Use a shaping mold to press the woven preform to fix its shape and prevent deformation during the deposition process;

[0053] 2.2. The preform after the finalization is subjected to interface deposition at a propylene flow rate of 0.1L / min to 20L / min and an argon flow rate of 0.5L / min to 21L / min. The deposition time is 10h to 80h and the deposition temperature is 400℃ to 1100℃. The number of deposition heats shall be based on the actual requirements of the interface. Here, taking the thick interface as an example, 2 to 8 heats of deposition are performed.

[0054] 2.3. The preform after interface deposition is subjected to high-temperature graphitization treatment at a temperature of 1500°C to 2500°C for 0.5h to 15h. After cooling in the furnace, a flat plate with a pyrolytic carbon interface is obtained.

[0055] Step 3: performing chemical vapor deposition on the flat plate having the pyrolytic carbon interface to form a SiC matrix inside the flat plate; specifically comprising:

[0056] 3.1. Remove the shaping mold;

[0057] 3.2. Chemical vapor deposition of SiC was performed on the flat plate having a pyrolytic carbon interface at a gas flow rate of 1 L / min to 15 L / min for trichloromethylsilane, 1 L / min to 15 L / min for argon, and 1 L / min to 15 L / min for hydrogen. The deposition temperature was 500°C to 1200°C and the deposition time was 20 h to 100 h to form a SiC matrix inside the flat plate.

[0058] Step 4: Impregnate the flat plate with the SiC substrate with the ultrahigh temperature particle slurry to contain ultrahigh temperature particles. In this embodiment, the ultrahigh temperature particle slurry is ZrB2 ultrahigh temperature powder. In other embodiments, it can also be HfB2, ZrC, HfC and / or SiC. Specifically, the process includes:

[0059] 4.1. Place the flat plate with the SiC substrate in an impregnation tank filled with ultrahigh temperature particle slurry and suspend it above the ultrahigh temperature particle slurry. Vacuum the impregnation tank for 10 to 45 minutes.

[0060] 4.2. Vacuuming: Immerse the flat plate in the ultra-high temperature particle slurry and vacuum immerse for 10 to 45 minutes;

[0061] 4.3. Vacuum impregnation: pressurize the inside of the impregnation tank to 0.2MPa~1.5MPa and impregnate under pressure for 10min~45min;

[0062] 4.4. Pressure impregnation: The impregnated flat plate is transferred to a drying oven for drying at a temperature of 30°C to 200°C to obtain a flat plate containing ultra-high temperature particles.

[0063] Step 5: Impregnate the flat plate containing the ultra-high temperature particles with resin so that the flat plate contains resin carbon. In this embodiment, phenolic resin is used. The process specifically includes:

[0064] 5.1. Vacuuming: Place the flat plate containing the ultra-high temperature particles in an impregnation tank filled with phenolic resin and suspend it above the phenolic resin. Vacuum the tank for 10 to 45 minutes.

[0065] 5.2 Vacuum impregnation: Immerse the plate in phenolic resin and vacuum impregnate for 10 to 45 minutes;

[0066] 5.3. Pressurized impregnation: pressurize the inside of the impregnation tank to 0.2MPa~1.5MPa and pressurize for 10min~45min;

[0067] 5.4. Place the impregnated plate in a drying oven at 30°C to 200°C for slow curing, with a curing time of 2h to 20h.

[0068] 5.5. The solidified flat plate is transferred to a cracking furnace for cracking at a cracking temperature of 600°C to 1500°C for 0.5h to 5h to obtain a flat plate containing phenolic resin carbon.

[0069] Step 6: Perform reactive melt infiltration on the flat plate containing phenolic resin carbon; specifically, weigh an appropriate amount of the prepared mixture, put it into a crucible lined with graphite paper and scrape it flat, place the flat plate on the scraped mixture, lay the mixture on it again and scrape it flat, and then compact it with a press. The thickness of the powder under the part is 10-15 mm, and perform reactive melt infiltration to obtain an ultra-high temperature modified C / SiC skin.

[0070] Example 1:

[0071] The preparation method of this embodiment is shown above, and its specific data are as follows:

[0072] In step 1, there are 5 layers of warp yarns, 10 layers of weft yarns, warp density 2 yarns / cm, weft density 10 yarns / cm, and thickness 2 mm.

[0073] In step 2, the propylene flow rate is 0.1 L / min, the argon flow rate is 21 L / min, the interface deposition time is 10 h, the interface deposition temperature is 400° C., and the interface deposition furnace number is 8 furnaces; the high-temperature graphitization treatment temperature is 1500° C., and the high-temperature graphitization treatment time is 10 h.

[0074] In step 3, the flow rate of trichloromethylsilane is 1 L / min, the flow rate of argon is 15 L / min, the flow rate of hydrogen is 10 L / min, the chemical vapor deposition temperature is 500° C., and the chemical vapor deposition time is 20 h.

[0075] In step 4, the impregnation tank containing the ultra-high temperature particle slurry is vacuumed for 45 minutes, the vacuum impregnation time is 10 minutes, the internal pressure of the slurry impregnation tank is increased to 0.5 MPa, and the pressurized impregnation time is 20 minutes; the drying temperature is 30°C.

[0076] In step 5, the impregnation tank containing phenolic resin is vacuumed for 10 minutes, vacuum impregnation is performed for 10 minutes, the interior of the resin impregnation tank is pressurized to 0.5 MPa, the pressurized impregnation time is 20 minutes, the drying oven temperature is 50°C, the curing time is 2 hours, the cracking temperature is 600°C, and the cracking time is 5 hours.

[0077] In step 6, the thickness of the powder under the part is 10mm.

[0078] The C / SiC skin obtained by this embodiment is as follows Figure 1 As shown by Figure 1 It can be seen that the cross section of the C / SiC skin flat plate after reactive melt infiltration is denser and the ultra-high temperature phase is more evenly distributed, indicating that the preform configuration obtained by the preform weaving parameters proposed in the present invention is more conducive to the subsequent slurry impregnation and resin impregnation, and improves the process adaptability of the C / SiC skin. Figure 1 (b) It can be seen that the ultrahigh temperature particles are evenly dispersed among the fiber bundles, indicating that the introduction of ultrahigh temperature particles can finely divide the pores and improve the density of the C / SiC skin.

[0079] Example 2:

[0080] The preparation method of this embodiment is shown above, and its specific data are as follows:

[0081] In step 1, there are 10 layers of warp yarn, 3 layers of weft yarn, warp density 10 yarns / cm, weft density 1 yarn / cm, and thickness 5 mm.

[0082] In step 2, the propylene flow rate is 10 L / min, the argon flow rate is 10 L / min, the interface deposition time is 40 h, the interface deposition temperature is 800° C., and the interface deposition furnace number is 4; the high-temperature graphitization treatment temperature is 2500° C., and the high-temperature graphitization treatment time is 0.5 h.

[0083] In step 3, the flow rate of trichloromethylsilane is 8 L / min, the flow rate of argon is 1 L / min, the flow rate of hydrogen is 1 L / min, the chemical vapor deposition temperature is 800° C., and the chemical vapor deposition time is 50 h.

[0084] In step 4, the impregnation tank containing the ultra-high temperature particle slurry is vacuumed for 10 minutes, the vacuum impregnation time is 20 minutes, the internal pressure of the slurry impregnation tank is increased to 1 MPa, and the pressurized impregnation time is 45 minutes; the drying temperature is 100°C.

[0085] In step 5, the impregnation tank containing phenolic resin is vacuumed for 20 minutes, vacuum impregnation is carried out for 45 minutes, the interior of the resin impregnation tank is pressurized to 1 MPa, the pressurized impregnation time is 45 minutes, the drying oven temperature is 100°C, the curing time is 10 hours, the cracking temperature is 950°C, and the cracking time is 0.5 hours.

[0086] In step 6, the thickness of the powder under the part is 12mm.

[0087] The C / SiC skin obtained in Example 2 is as follows Figure 2 As shown by Figure 2 It can be seen that the obtained C / SiC skin is relatively dense, and the fiber bundles are all filled with ultra-high temperature particles, SiC matrix and ultra-high temperature phase generated by RMI.

[0088] Example 3:

[0089] The preparation method of this embodiment is shown above, and its specific data are as follows:

[0090] In step 1, there are 24 layers of warp yarns, 23 layers of weft yarns, warp density 22 yarns / cm, weft density 15 yarns / cm, and thickness 10 mm.

[0091] In step 2, the propylene flow rate is 20 L / min, the argon flow rate is 0.5 L / min, the interface deposition time is 80 h, the interface deposition temperature is 1100° C., and the interface deposition furnace number is 2; the high-temperature graphitization treatment temperature is 2000° C., and the high-temperature graphitization treatment time is 15 h.

[0092] In step 3, the flow rate of trichloromethylsilane is 15 L / min, the flow rate of argon is 8 L / min, the flow rate of hydrogen is 15 L / min, the chemical vapor deposition temperature is 1200° C., and the chemical vapor deposition time is 100 h.

[0093] In step 4, the impregnation tank containing the ultra-high temperature particle slurry is vacuumed for 20 minutes, the vacuum impregnation time is 45 minutes, the internal pressure of the slurry impregnation tank is increased to 1.5 MPa, and the pressurized impregnation time is 10 minutes; the drying temperature is 200°C.

[0094] In step 5, the impregnation tank containing phenolic resin is vacuumed for 20 minutes, vacuum impregnation is 10 minutes, the inside of the resin impregnation tank is pressurized to 1.5 MPa, the pressurized impregnation time is 10 minutes, the drying oven temperature is 200°C, the curing time is 15 hours, the cracking temperature is 1500°C, and the cracking time is 2 hours.

[0095] In step 6, the thickness of the powder under the part is 15mm.

[0096] The micromorphology of the C / SiC skin obtained in Example 3 is as follows: Figure 3 As shown by Figure 3 It can be seen that the obtained C / SiC skin is relatively dense, and the fiber bundles are all filled with ultra-high temperature particles, SiC matrix and ultra-high temperature phase generated by RMI.

[0097] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention shall be covered by the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A method for preparing an ultra-high temperature modified C / SiC skin, characterized in that: The following steps are involved: Step 1: Prepare the prefabricated body; Step 2: performing interface deposition on the surface of the preform, and then performing high-temperature graphitization treatment to obtain a flat plate with a pyrolytic carbon interface; Step 3: chemical vapor deposition is performed on the plate with the pyrolytic carbon interface to form a SiC matrix inside the plate; Step 4: Impregnate the flat plate with the SiC substrate with the ultrahigh temperature particle slurry so that the flat plate contains ultrahigh temperature particles; Step 5: impregnate the plate containing the ultra-high temperature particles with resin, and then solidify and crack it in sequence to make it contain resin carbon; Step 6: Perform reactive melt infiltration treatment on the flat plate containing resin carbon to obtain an ultra-high temperature modified C / SiC skin.

2. The method for preparing the ultrahigh temperature modified C / SiC skin according to claim 1, characterized in that: Step 2 specifically includes shaping the preform using a shaping mold, performing interface deposition on the surface of the preform after shaping, and then performing high-temperature graphitization treatment to obtain a flat plate with a pyrolytic carbon interface; Step 3 specifically includes removing the shaping mold and performing chemical vapor deposition on the flat plate with the pyrolytic carbon interface to form a SiC matrix inside the flat plate.

3. The method for preparing the ultra-high temperature modified C / SiC skin according to claim 2, characterized in that: Step 2 specifically includes: 2.

1. Use the shaping mold to shape the preform; 2.

2. Deposition the preform after shaping at an interface with a propylene flow rate of 0.1 L / min to 20 L / min and an argon flow rate of 0.5 L / min to 21 L / min for 10 to 80 hours at a deposition temperature of 400° C. to 1100° C. for 2 to 8 heats. 2.

3. The preform after interface deposition is subjected to high-temperature graphitization treatment at a temperature of 1500°C to 2500°C for 0.5h to 15h. After cooling in the furnace, a flat plate with a pyrolytic carbon interface is obtained.

4. The method for preparing the ultrahigh temperature modified C / SiC skin according to claim 3, characterized in that: Step 3 specifically includes: 3.

1. Remove the shaping mold; 3.

2. Chemical vapor deposition is performed on the flat plate having a pyrolytic carbon interface at a gas flow rate of 1 L / min to 15 L / min of trichloromethylsilane, 1 L / min to 15 L / min of argon, and 1 L / min to 15 L / min of hydrogen. The deposition temperature is 500°C to 1200°C, and the deposition time is 20 h to 100 h to form a SiC matrix inside the flat plate.

5. The method for preparing the ultra-high temperature modified C / SiC skin according to claim 4, characterized in that: Step 4 specifically includes: 4.

1. Place the flat plate with the SiC substrate in an impregnation tank filled with ultrahigh temperature particle slurry and suspend it above the ultrahigh temperature particle slurry. Vacuum the impregnation tank for 10 to 45 minutes. 4.

2. Immerse the flat plate in the ultra-high temperature particle slurry and vacuum impregnate for 10 to 45 minutes; 4.

3. Pressurize the inside of the impregnation tank to 0.2MPa~1.5MPa and immerse for 10min~45min; 4.

4. The impregnated flat plate is transferred to a drying oven for drying at a temperature of 30°C to 200°C to obtain a flat plate containing ultra-high temperature particles.

6. The method for preparing the ultrahigh temperature modified C / SiC skin according to claim 5, characterized in that: Step 5 specifically includes: 5.

1. Place the flat plate containing the ultra-high temperature particles in an impregnation tank filled with resin and suspend it above the resin. Vacuum the tank for 10 to 45 minutes. 5.

2. Immerse the plate in the resin and vacuum impregnate for 10 to 45 minutes; 5.

3. Pressurize the inside of the impregnation tank to 0.2MPa~1.5MPa and immerse for 10min~45min; 5.

4. Place the impregnated plate in a drying oven at 30°C to 200°C for slow curing, with a curing time of 2h to 20h. 5.

5. The solidified flat plate is transferred to a cracking furnace for cracking at a cracking temperature of 600°C to 1500°C for 0.5h to 5h to obtain a flat plate containing resin carbon.

7. The method for preparing the ultrahigh temperature modified C / SiC skin according to claim 6, characterized in that: In step 4, the ultrahigh temperature particle slurry includes ZrB2, HfB2, ZrC, HfC and / or SiC.

8. The method for preparing the ultrahigh temperature modified C / SiC skin according to claim 7, characterized in that: In step 5.1, the resin is a phenolic resin.

9. The method for preparing the ultra-high temperature modified C / SiC skin according to any one of claims 1 to 8, characterized in that: Step 1 is as follows: The preform is woven with C fiber yarn, with 5 to 24 warp layers, 3 to 23 weft layers, 2 to 22 warp yarns / cm, 1 to 15 weft yarns / cm and a thickness of 2 mm to 10 mm.

10. An ultra-high temperature modified C / SiC skin, characterized by: The ultra-high temperature modified C / SiC skin is prepared by the preparation method of any one of claims 1 to 9.

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