阅读说明：本技术 一种陶瓷基复合材料耐热板及其制备方法 (Ceramic matrix composite heat-resistant plate and preparation method thereof ) 是由 张东生 马美霞 吴恒 魏庆勃 刘毫豪 曹伟 李江涛 潘广镇 董会娜 于 2021-01-27 设计创作，主要内容包括：本发明涉及一种陶瓷基复合材料耐热板及其制备方法,(1)根据设计制备纤维预制体；(2)制备界面层；(3)重复浸渍-固化-裂解2-6次；(4)照设计尺寸将耐热板制品加工通孔,并按照设计尺寸加工螺栓的头部和螺杆的外螺纹；(5)在螺栓和通孔的表面涂抹含纳米纤维的陶瓷先驱体浆料,将螺栓穿过耐热板的通孔；(6)重复浸渍-固化-低温裂解2-4次,再重复浸渍-固化-高温裂解1-2次；(7)CVI技术增密SiC基体；(8)CVD沉积SiC涂层即得陶瓷基复合材料耐热板。本发明所生产的耐热板耐高温,能有效的阻止发动机尾焰从缝隙进入耐热板背部烧蚀金属支架,延长金属支架寿命,降低使用成本。(The invention relates to a ceramic matrix composite heat-resistant plate and a preparation method thereof, (1) a fiber preform is prepared according to design; (2) preparing an interface layer; (3) repeating the steps of dipping, curing and cracking for 2-6 times; (4) processing a through hole on the heat-resistant plate product according to the design size, and processing the head of the bolt and the external thread of the screw according to the design size; (5) smearing ceramic precursor slurry containing nano fibers on the surfaces of the bolt and the through hole, and enabling the bolt to penetrate through the through hole of the heat-resistant plate; (6) repeating dipping-curing-low-temperature cracking for 2-4 times, and repeating dipping-curing-high-temperature cracking for 1-2 times; (7) densifying a SiC matrix by a CVI technology; (8) and depositing the SiC coating by CVD to obtain the ceramic matrix composite heat-resistant plate. The heat-resistant plate produced by the invention is high-temperature resistant, and can effectively prevent the tail flame of an engine from entering the back of the heat-resistant plate from a gap to ablate a metal bracket, thereby prolonging the service life of the metal bracket and reducing the use cost.)

1. A ceramic matrix composite heat-resistant plate is characterized in that: the heat-resistant plate is provided with a through hole which is in an inverted convex shape, namely the through hole comprises two parts, wherein the first part is a part close to the front part of the heat-resistant plate and has a large diameter, and the second part is a part close to the back part of the heat-resistant plate and has a small diameter; a bolt penetrates through the through hole; the screw rod of the bolt penetrates out of the through hole; the head surface of the bolt is flush with the front surface of the heat-resistant plate; the head of the bolt is in an inverted convex shape with the shape and the size consistent with those of the through hole, or the head of the bolt is in the same shape and the size as those of the first part of the through hole, and the diameter of the screw rod of the bolt is in the same size as that of the second part of the through hole; and a ceramic matrix is filled in a gap between the through hole and the bolt.

2. A ceramic matrix composite heat-resistant plate is characterized in that: the heat-resistant plate is provided with a through hole which is in an inverted convex shape, namely the through hole comprises two parts, wherein the first part is a part close to the front part of the heat-resistant plate and has a large diameter, and the second part is a part close to the back part of the heat-resistant plate and has a small diameter; a bolt penetrates through the through hole; the screw rod of the bolt penetrates out of the through hole; the head of the bolt sinks, namely the distance between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate is 2-4 mm; the head of the bolt is consistent with the shape of the through hole, the diameter of the head is consistent with the inner diameter of the through hole, the length of the head is 2-4mm smaller than that of the through hole, or the head of the bolt is consistent with the shape of a first part of the through hole, the diameter of the head is consistent with that of the first part, the length of the head is 2-4mm smaller than that of the first part, the diameter of a screw rod of the bolt is consistent with that of a second part, or the head of the bolt is consistent with that of the second part of the through hole in shape and size, and the length of the first part is 2-4 mm; a ceramic substrate is filled in a gap between the through hole and the bolt; and a ceramic matrix is filled between the head surface of the bolt in the through hole and the front surface of the heat-resistant plate.

3. A method of making a ceramic matrix composite refractory plate according to claim 1 or 2, wherein: the method comprises the following steps:

(1) preparing a prefabricated body: preparing fibers into fiber preforms which are consistent with the shapes of final products and have allowance in size, wherein the fiber preforms comprise heat-resistant plate fiber preforms and bolt fiber preforms;

(2) preparing an interface layer: depositing a pyrolytic carbon interface layer on the fiber preform obtained in the step (1) through CVI;

(3) dipping-curing-cracking: repeatedly dipping, curing and cracking the prefabricated body blank obtained in the step (2) for 2-6 times; the cracking comprises low-temperature cracking and/or high-temperature cracking, wherein the low-temperature cracking temperature is 950-1300 ℃, and the high-temperature cracking temperature is 1300-1500 ℃;

(4) and (3) machining: processing a heat-resistant plate product into a through hole according to the design size of the product obtained in the step (3), and processing the head of a bolt and the external thread of a screw according to the design size;

(5) installing bolts: firstly, smearing ceramic precursor slurry containing nano fibers on the surface of a bolt, smearing the ceramic precursor slurry containing the nano fibers on the inner surface of a through hole of a heat-resistant plate, and then penetrating the bolt through the through hole of the heat-resistant plate to connect the heat-resistant plate with the bolt; when the head of the installed bolt sinks, namely the distance between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate is 2-4mm, ceramic precursor slurry containing nano fibers needs to be smeared between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate;

(6) repeating dipping-curing-cracking: repeatedly dipping, curing and low-temperature cracking the product obtained in the step (5) for 2-4 times, and then repeatedly dipping, curing and high-temperature cracking for 1-2 times, wherein the dipping, curing and low-temperature cracking is 950-1300 ℃; the impregnation-solidification-pyrolysis is 1300-1500 ℃ pyrolysis;

(7) preparing a densified SiC matrix by CVI: in order to improve the matching strength of the bolt and the through hole, the product obtained in the step (6) is used for preparing a SiC matrix by adopting a CVI (chemical vapor infiltration) technology, and tiny pores at the joint of the bolt and the through hole are sealed;

(8) CVD deposition of SiC coating: and (4) coating a screw rod of the bolt extending out of the heat-resistant plate with carbon paper, then placing the coated screw rod into a chemical vapor deposition furnace, chemically vapor depositing a SiC coating on the surface of the product obtained in the step (7), and then removing the carbon paper to obtain the ceramic matrix composite heat-resistant plate.

4. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: in the step (1), the fiber is carbon fiber or silicon carbide fiber; the fiber preform is prepared by 2.5D needling and 2.5D puncture molding of fibers, and the density of the fiber preform is 0.4-0.6g/cm³。

5. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: the CVI deposition pyrolytic carbon interface layer in the step (2) is specifically as follows: fixing the fiber preform, introducing a carbon source gas at a flow rate of 5-15L/min, depositing a pyrolytic carbon interface layer on the surface of the fiber preform by adopting isothermal CVI, and naturally cooling to room temperature in an argon or nitrogen atmosphere; the carbon source gas is selected from any one or more of natural gas, methane, propane and propylene; the deposition temperature of the CVI is 800-1300 ℃, the deposition time is 1-60h, and the pressure in the furnace is 0.5-20 kPa.

6. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: the impregnation in the step (3) and the step (6) comprises vacuum impregnation and pressure impregnation;

the vacuum impregnation comprises the following steps: putting the product into a vacuum impregnation barrel, vacuumizing to below 200Pa, keeping the vacuum for 0.5-1h, injecting ceramic precursor slurry or ceramic precursor slurry containing nano ceramic powder, keeping the vacuum for 1-5h, breaking the vacuum and taking out;

the pressure impregnation comprises the following steps: putting the product into a pressure impregnation tank, heating to 50-70 ℃ under the pressure of 1-6MPa, preserving heat for 1-5h, cooling to room temperature along with a furnace, and taking out;

the ceramic precursor slurry is prepared by mixing a ceramic precursor and a solvent according to the mass ratio of 10 (3-8);

the ceramic precursor slurry containing the nano ceramic powder is prepared from a ceramic precursor, a solvent and the nano ceramic powder according to the weight ratio of 10: (3-8): (0.5-2) by mass;

the ceramic precursor is one or more of polymethylsilane, polycarbosilane, polysilazane, polysiloxane and polyborosilazane;

the solvent is one or more of divinylbenzene, xylene and toluene;

the nano ceramic powder is selected from any one or more of carbide, nitride and boride of silicon, zirconium and other transition metal elements.

7. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: the cracking in the step (3) and the step (6) is as follows: putting the product into a sintering furnace, heating at a rate of 5-10 ℃/min in a vacuum state below 200Pa or in a micro-positive pressure state with the pressure in the furnace of 100-200kPa for 2-10h, and naturally cooling to room temperature in an argon or nitrogen atmosphere.

8. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: the ceramic precursor slurry containing the nano-fibers in the step (5) is prepared from a ceramic precursor, a solvent and the nano-fibers according to the weight ratio of 10: (6-12): (1-3) by ball milling and uniformly mixing; the ceramic precursor is one or more of polymethylsilane, polycarbosilane, polysilazane, polysiloxane and polyborosilazane; the solvent is one or more of divinylbenzene, xylene and toluene; the nano-fiber is any one or more of nano-carbon fiber, carbon nano-tube, nano-SiC fiber and nano-ZrC fiber; the ball milling time is 3-5h, and the ball milling rotating speed is 300-400 r/min.

9. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: the CVI preparation of the densified SiC matrix in the step (7) specifically comprises the following steps: the product is put into a chemical vapor infiltration furnace, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluting gas, the deposition temperature is 850-1100 ℃, the deposition time is 5-100h, the deposition pressure is 5-15kPa, the molar ratio of the reducing gas to the trichlorosilane is (5-15): 1, the flow rate of the precursor is 5-10g/min, the flow rate of the diluting gas is 5-10L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 200-400 mL/min.

10. The method of making a ceramic matrix composite heat resistant panel of claim 3, wherein: the CVD deposition SiC coating in the step (8) is specifically as follows: the product is put into a chemical vapor deposition furnace, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluting gas, the deposition temperature of the chemical vapor deposition is 1000-1500 ℃, the deposition time is 5-100h, the deposition pressure is 1-20kPa, the molar ratio of the reducing gas to the trichlorosilane is 8-20:1, the flow rate of the precursor is 1-15g/min, the flow rate of the diluting gas is 2-20L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 100-200 mL/min.

Technical Field

The invention belongs to the technical field of heat-resistant plates, and particularly relates to a ceramic matrix composite heat-resistant plate suitable for high-temperature, high-speed and high-pressure airflow scouring protection and a preparation method thereof.

Background

The engine tail flame flows away through the cooperation of the heat-resistant plate and the metal lifting platform, the existing method that the heat-resistant plate is connected with the back metal supporting structure through a through hole arranged in the heat-resistant plate and a screw or a bolt is connected with the back metal supporting structure is mostly adopted, although the connection strength of the connection mode is high, the high-temperature resistance performance of the used high-temperature alloy screw or bolt cannot meet the actual use requirement, the connection failure between the heat-resistant plate and the metal lifting platform is caused, the maintenance times are increased, the engine tail flame can enter the back of the heat-resistant plate along the gap between the screw and the through hole of the heat-resistant plate, and the metal supporting structure and the cooling system are damaged.

The heat-resistant plate and the metal supporting structure are connected through the metal screws, high-temperature heat flow can be quickly transferred to the back of the heat-resistant plate through the metal screws, if cooling is not timely, the temperature of the metal supporting structure can be rapidly improved, the mechanical strength of the metal supporting structure can be reduced, and the risk of accident occurrence is increased. In addition, the high-temperature alloy material is expensive, the metal bracket is generally made of a steel material which cannot resist high temperature, the temperature of heat transmitted through the screw reaches thousands of degrees, the phase of the material of the supporting structure is easily changed, the performance of the metal material is reduced, the service life is shortened, and the maintenance cost is increased.

Disclosure of Invention

Aiming at the problems that the connecting piece is easy to lose efficacy at high temperature, a screw or a bolt conducts heat, a through hole is easy to enter flame to cause strength reduction or invalidation of a metal supporting structure and other structural systems and the like in the connection mode of the conventional heat-resistant plate and a back metal supporting structure, the invention provides the heat-resistant plate made of the ceramic matrix composite material, and the problems in the prior art are perfectly solved.

The invention also provides a preparation method of the ceramic matrix composite heat-resistant plate.

A ceramic matrix composite heat-resistant plate is provided with a through hole, the through hole is in an inverted convex shape, namely the through hole comprises two parts, the first part is a part with a large diameter close to the front part of the heat-resistant plate, and the second part is a part with a small diameter close to the back part of the heat-resistant plate; a bolt penetrates through the through hole; the screw rod of the bolt penetrates out of the through hole; the head surface of the bolt is flush with the front surface of the heat-resistant plate; the head of the bolt is in an inverted convex shape with the shape and the size consistent with those of the through hole, or the head of the bolt is in the same shape and the size as those of the first part of the through hole, and the diameter of the screw rod of the bolt is in the same size as that of the second part of the through hole; and a ceramic matrix is filled in a gap between the through hole and the bolt.

A ceramic matrix composite heat-resistant plate is provided with a through hole, the through hole is in an inverted convex shape, namely the through hole comprises two parts, the first part is a part with a large diameter close to the front part of the heat-resistant plate, and the second part is a part with a small diameter close to the back part of the heat-resistant plate; a bolt penetrates through the through hole; the screw rod of the bolt penetrates out of the through hole; the head of the bolt sinks, namely the distance between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate is 2-4 mm; the head of the bolt is consistent with the shape of the through hole, the diameter of the head is consistent with the inner diameter of the through hole, the length of the head is 2-4mm smaller than that of the through hole, or the head of the bolt is consistent with the shape of a first part of the through hole, the diameter of the head is consistent with that of the first part, the length of the head is 2-4mm smaller than that of the first part, the diameter of a screw rod of the bolt is consistent with that of a second part, or the head of the bolt is consistent with that of the second part of the through hole in shape and size, and the length of the first part is 2-4 mm; a ceramic substrate is filled in a gap between the through hole and the bolt; and a ceramic matrix is filled between the head surface of the bolt in the through hole and the front surface of the heat-resistant plate.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a preparation method of the ceramic matrix composite heat-resistant plate, which comprises the following steps:

(1) preparing a prefabricated body: preparing fibers into fiber preforms which are consistent with the shapes of final products and have allowance in size, wherein the fiber preforms comprise heat-resistant plate fiber preforms and bolt fiber preforms;

(2) preparing an interface layer: depositing a pyrolytic carbon interface layer on the fiber preform obtained in the step (1) through CVI;

(3) dipping-curing-cracking: repeatedly dipping, curing and cracking the prefabricated body blank obtained in the step (2) for 2-6 times; the cracking comprises low-temperature cracking and/or high-temperature cracking, wherein the low-temperature cracking temperature is 950-1300 ℃, and the high-temperature cracking temperature is 1300-1500 ℃;

(4) and (3) machining: processing a heat-resistant plate product into a through hole according to the design size of the product obtained in the step (3), and processing the head of a bolt and the external thread of a screw according to the design size;

(5) installing bolts: firstly, smearing ceramic precursor slurry containing nano fibers on the surface of a bolt, smearing the ceramic precursor slurry containing the nano fibers on the inner surface of a through hole of a heat-resistant plate, and then penetrating the bolt through the through hole of the heat-resistant plate to connect the heat-resistant plate with the bolt; when the head of the installed bolt sinks, namely the distance between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate is 2-4mm, ceramic precursor slurry containing nano fibers needs to be smeared between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate;

(6) repeating dipping-curing-cracking: repeatedly dipping, curing and low-temperature cracking the product obtained in the step (5) for 2-4 times, and then repeatedly dipping, curing and high-temperature cracking for 1-2 times, wherein the dipping, curing and low-temperature cracking is 950-1300 ℃; the impregnation-solidification-pyrolysis is 1300-1500 ℃ pyrolysis;

(7) preparing a densified SiC matrix by CVI: in order to improve the matching strength of the bolt and the through hole, the product obtained in the step (6) is used for preparing a SiC matrix by adopting a CVI (chemical vapor infiltration) technology, and tiny pores at the joint of the bolt and the through hole are sealed;

(8) CVD deposition of SiC coating: and (4) coating a screw rod of the bolt extending out of the heat-resistant plate with carbon paper, then placing the coated screw rod into a chemical vapor deposition furnace, chemically vapor depositing a SiC coating on the surface of the product obtained in the step (7), and then removing the carbon paper to obtain the ceramic matrix composite heat-resistant plate.

Further, in the step (1), the fiber is carbon fiber or silicon carbide fiber; the fiber preform is prepared by 2.5D needling and 2.5D puncture molding of fibers, and the density of the fiber preform is 0.4-0.6g/cm³。

Further, the CVI deposited pyrolytic carbon interface layer in step (2) is specifically: fixing the fiber preform, introducing a carbon source gas at a flow rate of 5-15L/min, depositing a pyrolytic carbon interface layer on the surface of the fiber preform by adopting isothermal CVI, and naturally cooling to room temperature in an argon or nitrogen atmosphere; the carbon source gas is selected from any one or more of natural gas, methane, propane and propylene; the deposition temperature of the CVI is 800-1300 ℃, the deposition time is 1-60h, and the pressure in the furnace is 0.5-20 kPa.

Further, the impregnation in the step (3) and the step (6) includes vacuum impregnation and pressure impregnation;

the vacuum impregnation comprises the following steps: putting the product into a vacuum impregnation barrel, vacuumizing to below 200Pa, keeping the vacuum for 0.5-1h, injecting ceramic precursor slurry or ceramic precursor slurry containing nano ceramic powder, keeping the vacuum for 1-5h, breaking the vacuum and taking out;

the pressure impregnation comprises the following steps: putting the product into a pressure impregnation tank, heating to 50-70 ℃ under the pressure of 1-6MPa, preserving heat for 1-5h, cooling to room temperature along with a furnace, and taking out.

Further, the curing in the step (3) and the step (6) is as follows: the product is put into a blast drying box, heated to 120 ℃ and 250 ℃ at the heating rate of 5-10 ℃/min, and the heat preservation time is 3-10h, and is naturally cooled to the room temperature along with the furnace and then taken out.

Further, the cracking in step (3) and step (6) is: putting the product into a sintering furnace, heating at a rate of 5-10 ℃/min in a vacuum state below 200Pa or in a micro-positive pressure state with the pressure in the furnace of 100-200kPa for 2-10h, and naturally cooling to room temperature in an argon or nitrogen atmosphere.

Further, the ceramic precursor slurry is prepared by mixing a ceramic precursor and a solvent according to the mass ratio of 10 (3-8);

the ceramic precursor slurry containing the nano ceramic powder is prepared from a ceramic precursor, a solvent and the nano ceramic powder according to the weight ratio of 10: (3-8): (0.5-2) by mass;

the ceramic precursor is one or more of polymethylsilane, polycarbosilane, polysilazane, polysiloxane and polyborosilazane;

the solvent is one or more of divinylbenzene, xylene and toluene;

the nano ceramic powder is selected from any one or more of carbide, nitride and boride of silicon, zirconium and other transition metal elements.

Further, the cracking in step (3) and step (6) is: : putting the product into a sintering furnace, heating at a rate of 5-10 ℃/min in a vacuum state below 200Pa or in a micro-positive pressure state with the pressure in the furnace of 100-200kPa for 2-10h, and naturally cooling to room temperature in an argon or nitrogen atmosphere.

Further, the ceramic precursor slurry containing the nano-fibers in the step (5) is prepared by mixing the ceramic precursor, the solvent and the nano-fibers according to the weight ratio of 10: (6-12): (1-3) by ball milling and uniformly mixing; the ceramic precursor is one or more of polymethylsilane, polycarbosilane, polysilazane, polysiloxane and polyborosilazane; the solvent is one or more of divinylbenzene, xylene and toluene; the nano-fiber is any one or more of nano-carbon fiber, carbon nano-tube, nano-SiC fiber and nano-ZrC fiber; the ball milling time is 3-5h, and the ball milling rotating speed is 300-400 r/min.

Further, the CVI preparation of the densified SiC matrix in the step (7) specifically comprises the following steps: the product is put into a chemical vapor infiltration furnace, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluting gas, the deposition temperature is 850-1100 ℃, the deposition time is 5-100h, the deposition pressure is 5-15kPa, the molar ratio of the reducing gas to the trichlorosilane is (5-15): 1, the flow rate of the precursor is 5-10g/min, the flow rate of the diluting gas is 5-10L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 200-400 mL/min.

Further, the CVD deposited SiC coating of step (8) is specifically: the product is put into a chemical vapor deposition furnace, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluting gas, the deposition temperature of the chemical vapor deposition is 1000-1500 ℃, the deposition time is 5-100h, the deposition pressure is 1-20kPa, the molar ratio of the reducing gas to the trichlorosilane is 8-20:1, the flow rate of the precursor is 1-15g/min, the flow rate of the diluting gas is 2-20L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 100-200 mL/min.

Compared with the prior art, the invention has the following beneficial effects:

(1) according to the invention, the through hole of the heat-resistant plate is processed into an inverted convex shape, the bolt with the same shape and size as the through hole penetrates through the through hole, and the ceramic matrix is filled in the gap between the bolt and the through hole, so that the tail flame of an engine can be effectively prevented from entering the back of the heat-resistant plate from the gap to ablate the metal bracket, the service life of the metal bracket is prolonged, and the use cost is reduced;

(2) the ceramic matrix composite material bolt is adopted to replace a high-temperature alloy bolt to connect the heat-resistant plate and the metal supporting structure, so that the high-temperature resistance is realized, the heat conductivity is reduced, the heat transfer speed is low, the bolt and the heat-resistant plate are densified to a certain degree and then connected into a whole, the gap at the joint can be filled with the ceramic matrix to prevent flame from permeating, the same material is adopted, and the thermal expansion coefficients of the heat-resistant plate and the bolt are matched better at high temperature;

(3) the depth of the first part of the through hole of the heat-resistant plate is greater than the height of the head of the bolt, after the bolt is installed, the head of the bolt is away from the surface layer of the heat-resistant plate by a certain distance, and finally, the through hole is sealed by adopting ceramic slurry to completely prevent the tail flame of the engine from permeating; (4) according to the invention, the ceramic precursor containing the nano-fibers is coated as a reinforcing phase before the bolt is connected with the through hole, so that the phenomenon of poor sealing and filling effects at the gap caused by the fact that slurry in the gap does not well infiltrate in the subsequent dipping and cracking process can be avoided, and the connection strength between the bolt and the through hole substrate can be improved;

(5) according to the invention, the external thread of the bolt is processed when the density is lower, so that the situation that the thread is cracked and fallen in the preparation process can be effectively avoided, and the product percent of pass is ensured;

(6) according to the invention, a densification process of preparing the SiC matrix by CVI is added after the impregnation-solidification-cracking process, and the gas-phase ceramic precursor permeates into micro pores and is cracked into the SiC matrix to fill the micro pores, so that the joint is more dense, and the joint strength of the bolt and the heat-resistant plate is further improved.

(7) A SiC coating is deposited on the surface of the product through chemical vapor deposition, so that the oxidation resistance and the wear resistance of the heat-resistant plate are improved, and the bonding strength of the bolt and the heat-resistant plate is improved;

(8) the carbon paper is coated on the surface of the screw rod of the bolt before chemical vapor deposition and then removed after the deposition is finished, so that the influence of the surface deposition on the screw thread precision of the bolt in the deposition process can be effectively avoided, and the influence on the combination of a subsequent heat-resistant plate and a metal support frame is further avoided.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below in conjunction with the implementation of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Example 1

A ceramic matrix composite heat-resistant plate is provided with a through hole, the through hole is in an inverted convex shape, namely the through hole comprises two parts, the first part is a part with a large diameter close to the front part of the heat-resistant plate, and the second part is a part with a small diameter close to the back part of the heat-resistant plate; a bolt penetrates through the through hole, and the head of the bolt is in an inverted convex shape which is consistent with the shape and size of the through hole; the screw rod of the bolt penetrates out of the through hole; and a ceramic matrix is filled in a gap between the through hole and the bolt.

The preparation method of the ceramic matrix composite heat-resistant plate comprises the following steps:

(1) preparing a prefabricated body: the heat-resistant plate fiber preform and the bolt fiber preform are prepared in a manner of 0/90 degrees 2.5D needling forming of the carbon fiber (12K) laid fabric-mesh tire according to the component selection.

(2) CVI deposition of a pyrolytic carbon interface layer: fixing the fiber preform obtained in the step (1) by using a graphite tool, introducing methane gas at a gas flow rate of 10L/min, depositing a pyrolytic carbon interface layer on the surface of the fiber preform by adopting an isothermal CVI technology, wherein the deposition temperature is 1150 ℃, the deposition time is 30 hours, the pressure in a furnace is 10kPa, and then naturally cooling to the room temperature under the atmosphere of argon or nitrogen to obtain a preform body.

(3) Dipping-curing-cracking:

(3a) vacuum impregnation: putting the preform blank obtained in the step (2) into a vacuum impregnation barrel, firstly vacuumizing for 1h, keeping the vacuum degree below 100Pa, injecting ceramic precursor slurry after the vacuum is maintained for 1h, keeping the vacuum for 1h, breaking the vacuum and taking out the preform to obtain a preform containing the precursor slurry; the ceramic precursor slurry is prepared by uniformly mixing polycarbosilane and xylene according to a mass ratio of 10:5 through mechanical stirring, and stirring for 5 hours at a rotating speed of 50r/min in a 70 ℃ water bath kettle through mechanical stirring.

(3b) Pressure impregnation: and (4) putting the prefabricated body obtained in the step (3 a) into a pressure impregnation tank, slowly heating to 50 ℃ under the pressure of 1MPa in the impregnation tank, preserving heat for 2 hours, cooling to room temperature along with a furnace, and taking out.

(3c) And (3) curing: curing the preform obtained in step (3 b): putting into a blast drying oven, heating to 120 ℃ at a heating rate of 10 ℃/min, preserving heat for 10h, naturally cooling to room temperature along with the furnace, and taking out.

(3d) Low-temperature cracking: subjecting the preform obtained in step (3 c) to cryogenic cracking: putting the prefabricated body into a sintering furnace, heating the furnace to a low-temperature cracking temperature of 1000 ℃ at a heating rate of 10 ℃/min in a vacuum state below 200Pa, preserving the temperature for 2h, and then naturally cooling to room temperature in an argon or nitrogen atmosphere;

(3e) high-temperature cracking: carrying out pyrolysis on the preform obtained in the step (3 d): putting the prefabricated body into a sintering furnace, heating the furnace to the high-temperature cracking temperature of 1400 ℃ at the heating rate of 10 ℃/min in a vacuum state below 200Pa, preserving the heat for 2 hours, and then naturally cooling the prefabricated body to the room temperature in the argon or nitrogen atmosphere;

(3f) performing the steps (3 a) to (3 e) on the product obtained in the step (3 e), and repeating the steps for 4 times;

(4) and (3) machining: and (4) processing a through hole of the heat-resistant plate product obtained in the step (3) according to a design size, and processing the bolt head, the bolt screw and the external thread of the bolt screw of the bolt product obtained in the step (3) according to the design size.

(5) Installing a stud: firstly, smearing ceramic precursor slurry containing nano fibers on the surface of a bolt, then smearing the ceramic precursor slurry containing the nano fibers on the inner surface of a through hole of a heat-resistant plate, and then penetrating the bolt through the through hole of the heat-resistant plate to connect the heat-resistant plate with the bolt; the ceramic precursor slurry containing the nano-fibers is prepared from a ceramic precursor, a solvent and the nano-fibers according to the following steps of: solvent: the mass ratio of the nano fibers =10:5:1 is formed by ball milling and uniform mixing; the ceramic precursor is polycarbosilane; the solvent is xylene; the nano-fiber is nano-carbon fiber, and the ball milling time is 3 h; the ball milling speed is 300 r/min.

(6) Repeating dipping-curing-cracking: firstly, carrying out low-temperature cracking, namely, carrying out steps (3 a) - (3 d) on the product obtained in the step (5), and repeating for 2 times; then pyrolysis, i.e., continuing steps (3 a) - (3 c) and step (3 e), was repeated 2 times, and the density of the obtained product was 1.9g/cm³(ii) a The technological parameters of impregnation and solidification in the impregnation-solidification-cracking process are the same as the technological parameters of (3 a) vacuum impregnation, (3 b) pressure impregnation and (3 c) solidification in the step (3).

(7) Preparing a densified SiC matrix by CVI: in order to improve the matching strength of the bolt and the heat-resistant plate, the product obtained in the step (6) is used for preparing a SiC matrix by adopting a CVI (chemical vapor infiltration) technology, and tiny pores in the deep part of the joint of the heat-resistant plate and the bolt are sealed and filled; the product is placed in a chemical vapor infiltration furnace, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluting gas, the deposition temperature is 850 ℃, the deposition time is 100 hours, the deposition pressure is 5kPa, the molar ratio of the reducing gas to trichlorosilane is 15:1, the flow rate of the precursor is 10g/min, the flow rate of the diluting gas is 10L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 200 mL/min.

(8) CVD deposition of SiC coating: ultrasonically cleaning and drying the product obtained in the step (7) by using ethanol, coating a screw rod of a stud extending out of the heat-resistant plate by using carbon paper, then putting the product into a chemical vapor deposition furnace, taking silicon source trichlorosilane as a precursor, hydrogen as carrier gas and reducing gas, argon as diluent gas, setting the deposition temperature of the chemical vapor deposition to be 1000 ℃, the deposition time to be 100 hours, the deposition pressure to be 10kPa, the molar ratio of the reducing hydrogen to the trichlorosilane to be 8:1, the flow rate of the precursor to be 15g/min, the flow rate of the diluent gas to be 20L/min, the flow rate of the reducing gas to be determined by the molar ratio of the reducing gas to the silicon source, the flow rate of the carrier gas to be 200mL/min, preparing a SiC coating on the surface of the product by chemical vapor deposition, improving the oxidation resistance and the wear resistance of the component, and then removing the carbon paper ceramic-based composite material heat-, the density of the obtained product is 1.99g/cm³。

Example 2

A ceramic matrix composite heat-resistant plate is provided with a through hole, the through hole is in an inverted convex shape, namely the through hole comprises two parts, the first part is a part with a large diameter close to the front part of the heat-resistant plate, and the second part is a part with a small diameter close to the back part of the heat-resistant plate; a bolt penetrates through the through hole; the screw rod of the bolt penetrates out of the through hole; the head of the bolt sinks, namely the distance between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate is 2 mm; the head of the bolt is consistent with the shape of the through hole, the diameter of the head is consistent with the inner diameter of the through hole, the length of the head is 2mm less than that of the through hole, and a ceramic matrix is filled in a gap between the through hole and the bolt; and a ceramic matrix is filled between the head surface of the bolt in the through hole and the front surface of the heat-resistant plate.

The preparation method of the carbon ceramic matrix composite heat-resistant plate comprises the following steps:

(1) preparing a prefabricated body: selecting carbon fiber (12K) cloth for 2.5D puncture according to components to prepare a heat-resistant plate fiber preform and a bolt fiber preform.

(2) CVI deposition of a pyrolytic carbon interface layer: and (2) fixing the preform obtained in the step (1) by using a graphite tool, then introducing propane gas at a gas flow rate of 15L/min, and depositing a pyrolytic carbon interface layer on the surface of the preform by adopting an isothermal CVI technology, wherein the deposition temperature is 800 ℃, the deposition time is 60 hours, and the pressure in the furnace is 20 kPa. And then naturally cooling to room temperature in the argon or nitrogen atmosphere to obtain a preform body.

(3) Cyclic impregnation-curing-cracking:

(3a) vacuum impregnation: putting the preform blank obtained in the step (2) into a vacuum impregnation barrel, vacuumizing for 1h at the vacuum degree of below 200Pa for 0.5h, injecting ceramic precursor slurry, vacuumizing for 5h, and taking out the preform after vacuum breaking to obtain a preform containing the precursor slurry; the ceramic precursor slurry is prepared by uniformly mixing polymethyl silane and divinyl benzene in a mass ratio of 10:5 through mechanical stirring, and stirring for 10 hours at a rotating speed of 60r/min in a water bath kettle at 50 ℃ through mechanical stirring.

(3b) Pressure impregnation: and (4) putting the prefabricated body obtained in the step (3 a) into a pressure impregnation tank, slowly heating to 70 ℃ under the pressure of 6MPa in the impregnation tank, preserving heat for 1h, cooling to room temperature along with a furnace, and taking out.

(3c) And (3) curing: curing the preform obtained in step (3 b): putting into a blast drying oven, heating to 250 ℃ at the heating rate of 5 ℃/min, preserving heat for 3h, naturally cooling to room temperature along with the furnace, and taking out.

(3d) Low-temperature cracking: subjecting the preform obtained in step (3 c) to cryogenic cracking: putting the prefabricated body into a sintering furnace, heating to a low-temperature cracking temperature of 850 ℃ at a heating rate of 5 ℃/min under a micro-positive pressure state with the pressure of 100kPa, preserving heat for 2h, and then naturally cooling to room temperature under the atmosphere of argon or nitrogen;

(3e) vacuum impregnation: putting the blank prefabricated body obtained in the step (3 d) into a vacuum impregnation barrel, vacuumizing for 1h at the vacuum degree of below 200Pa for 0.5h, injecting ceramic precursor slurry, vacuumizing for 5h, and taking out after vacuum breaking to obtain a prefabricated body containing the precursor slurry; the ceramic precursor is formed by uniformly mixing polymethyl silicane and divinyl benzene according to the mass ratio of 10:5 through mechanical stirring, and the ceramic precursor is stirred for 10 hours at the rotating speed of 60r/min in a water bath kettle at the temperature of 50 ℃ through mechanical stirring.

(3f) Pressure impregnation: and (4) putting the prefabricated body obtained in the step (3 e) into a pressure impregnation tank, slowly heating to 70 ℃ under the pressure of 6MPa in the impregnation tank, preserving heat for 1h, cooling to room temperature along with a furnace, and taking out.

(3g) And (3) curing: curing the preform obtained in step (3 f): putting into a blast drying oven, heating to 250 ℃ at the heating rate of 5 ℃/min, preserving heat for 3h, naturally cooling to room temperature along with the furnace, and taking out.

(3h) High-temperature cracking: subjecting the preform obtained in step (3 g) to pyrolysis: putting the prefabricated body into a sintering furnace, heating the furnace to the high-temperature cracking temperature of 1400 ℃ at the heating rate of 10 ℃/min in a vacuum state below 200Pa, preserving the heat for 2 hours, and then naturally cooling the prefabricated body to the room temperature in the argon or nitrogen atmosphere;

(3i) and (4) carrying out steps (3 a) - (3 h) on the product obtained in the step (3 h), and repeating for 3 times.

(4) And (3) machining: and (4) processing through holes on the heat-resistant plate product obtained in the step (3) according to the design size, and processing the head of the bolt, the screw of the bolt and the external thread of the screw according to the design size.

(5) Installing a stud: firstly, smearing ceramic precursor slurry containing nano fibers on the surface of a bolt, smearing the ceramic precursor slurry containing the nano fibers on the inner surface of a through hole of a heat-resistant plate, and then penetrating the bolt through the through hole of the heat-resistant plate to connect the bolt with the heat-resistant plate; after installation, smearing ceramic precursor slurry containing nano fibers between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate; the ceramic precursor slurry containing the nano-fibers is prepared from a ceramic precursor, a solvent and the nano-fibers according to the weight ratio of 10: 12: 1 is prepared by ball milling and even mixing; the ceramic precursor is polymethyl silicane; the solvent is divinylbenzene; the nano-fiber is a nano-ZrC fiber; the ball milling time is 3h, and the ball milling speed is 300 r/min.

(6) Repeating dipping-curing-cracking: firstly, carrying out low-temperature cracking, namely, carrying out steps (3 a) - (3 d) on the product obtained in the step (5), and repeating for 2 times; and (4) then carrying out high-temperature cracking, namely continuing to carry out the steps (3 e) - (3 h), repeating for 2 times, and filling ceramic precursor slurry between the head surface of the bolt in the through hole and the front surface of the heat-resistant plate during impregnation, wherein the ceramic precursor slurry is filled in a gap between the through hole and the bolt.

(7) Preparing a densified SiC matrix by CVI: in order to improve the matching strength of the bolt and the heat-resistant plate, the product obtained in the step (6) is used for preparing a SiC matrix by adopting a CVI (chemical vapor infiltration) technology, and tiny pores in the deep part of the joint of the bolt and the heat-resistant plate are sealed; the product is put into a chemical vapor infiltration furnace, a strong convection CVI technology is adopted, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluent gas, the deposition temperature is 1100 ℃, the deposition time is 10 hours, the deposition pressure is 10kPa, the molar ratio of the reducing gas to the trichlorosilane is 10:1, the flow rate of the precursor is 8g/min, the flow rate of the diluent gas is 8L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 200 mL/min.

(8) CVD deposition of SiC coating: ultrasonically cleaning and drying the product obtained in the step (7) by using ethanol, coating a screw rod of a bolt extending out of a through hole of the heat-resistant plate by using carbon paper, then putting the product into a chemical vapor deposition furnace, taking trichlorosilane as a precursor, hydrogen as a carrier gas and a reducing gas, argon as a diluting gas, wherein the deposition temperature of the chemical vapor deposition is 1400 ℃, the deposition time is 5 hours, the deposition pressure is 20kPa, the molar ratio of the reducing hydrogen to the trichlorosilane is 8:1, the flow rate of the precursor is 15g/min, the flow rate of the diluting gas is 20L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, the flow rate of the carrier gas is 200mL/min, preparing a SiC coating on the surface of the product by chemical vapor deposition, improving the oxidation resistance and the wear resistance of the component, and then removing the carbon paper to obtain the heat-resistant plate connecting piece made, the density of the obtained product is 1.98g/cm³。

Example 3

A ceramic matrix composite heat-resistant plate is provided with a through hole, the through hole is in an inverted convex shape, namely the through hole comprises two parts, the first part is a part with a large diameter close to the front part of the heat-resistant plate, and the second part is a part with a small diameter close to the back part of the heat-resistant plate; a bolt penetrates through the through hole; the screw rod of the bolt penetrates out of the through hole; the head of the bolt sinks, namely the distance between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate is 4 mm; the head of the bolt is consistent with the first part of the through hole in shape, the diameter of the head is consistent with the inner diameter of the first part, the length of the head is 4mm smaller than that of the first part, and the diameter of a screw rod of the bolt is consistent with that of the second part; a ceramic substrate is filled in a gap between the through hole and the bolt; and a ceramic matrix is filled between the head surface of the bolt in the through hole and the front surface of the heat-resistant plate.

The preparation method of the carbon ceramic matrix composite heat-resistant plate comprises the following steps:

(1) preparing a prefabricated body: and (3) selecting carbon fiber cloth for 2.5D puncture according to the components to prepare a heat-resistant plate fiber preform and a bolt fiber preform.

(2) CVI deposition of a pyrolytic carbon interface layer: and (2) fixing the preform obtained in the step (1) by using a graphite tool, then introducing propane gas at a gas flow rate of 5L/min, and depositing a pyrolytic carbon interface layer on the surface of the preform by adopting an isothermal CVI technology, wherein the deposition temperature is 1300 ℃, the deposition time is 1h, and the pressure in the furnace is 0.5 kPa. And then naturally cooling to room temperature in the argon or nitrogen atmosphere to obtain a preform body.

(3) Cyclic impregnation-curing-cracking:

(3a) vacuum impregnation: putting the preform blank obtained in the step (2) into a vacuum impregnation barrel, vacuumizing for 1h, keeping the vacuum degree below 200Pa, injecting ceramic precursor slurry after keeping the vacuum for 0.8h, keeping the vacuum for 3h, breaking the vacuum and taking out to obtain a preform containing the precursor slurry; the ceramic precursor slurry is prepared from polycarbosilazane: the tetrahydrofuran is prepared by uniformly mixing the tetrahydrofuran by mechanical stirring according to the mass ratio of 10:5, and stirring the tetrahydrofuran by mechanical stirring for 10 hours in a water bath kettle at the temperature of 50 ℃ at the rotating speed of 60 r/min.

(3b) Pressure impregnation: and (4) putting the prefabricated body obtained in the step (3 a) into a pressure impregnation tank, slowly heating to 70 ℃ under the pressure of 6MPa in the impregnation tank, preserving heat for 1h, cooling to room temperature along with a furnace, and taking out.

(3c) And (3) curing: curing the preform obtained in step (3 b): putting into a blast drying oven, heating to 250 ℃ at the heating rate of 5 ℃/min, preserving heat for 3h, naturally cooling to room temperature along with the furnace, and taking out.

(3d) Low-temperature cracking: subjecting the preform obtained in step (3 c) to cryogenic cracking: putting the prefabricated body into a sintering furnace, heating to a low-temperature cracking temperature of 850 ℃ at a heating rate of 5 ℃/min under a micro-positive pressure state with the pressure of 100kPa, preserving heat for 2h, and then naturally cooling to room temperature under the atmosphere of argon or nitrogen;

(3e) repeating the steps (3 a) - (3 d) for 3 times on the product obtained in the step (3 d);

(3f) vacuum impregnation: putting the prefabricated body obtained in the step (3 e) into a vacuum impregnation barrel, vacuumizing for 1h, keeping the vacuum degree below 200Pa, keeping the vacuum for 0.5h, injecting ceramic precursor slurry containing the nano ceramic powder, keeping the vacuum for 5h, breaking the vacuum and taking out to obtain the prefabricated body of the ceramic precursor containing the nano ceramic powder; the ceramic precursor slurry containing the nano ceramic powder is prepared from polymethyl silane, tetrahydrofuran and silicon carbide according to the weight ratio of 10:5: 2, and stirring the mixture in a water bath kettle at the temperature of 70 ℃ for 1 hour at the rotating speed of 50r/min by mechanical stirring.

(3g) Pressure impregnation: and (4) putting the prefabricated body obtained in the step (3 f) into a pressure impregnation tank, injecting the ceramic precursor slurry containing the nano ceramic powder in the step (3 f) into the impregnation tank, slowly heating to 60 ℃ under the pressure of 6MPa in the impregnation tank, preserving heat for 3h, cooling to room temperature along with a furnace, and taking out.

(3h) And (3) curing: curing the preform obtained in step (3 f): putting into a forced air drying oven, heating to 200 ℃ at a heating rate of 8 ℃/min, keeping the temperature for 5h, naturally cooling to room temperature along with the furnace, and taking out.

(3i) High-temperature cracking: carrying out high-temperature cracking on the preform obtained in the step (3 g), raising the temperature to 1500 ℃ at a heating rate of 10 ℃/min under a micro-positive pressure state with the pressure in the furnace being 200kPa, preserving the temperature for 10h, and then naturally cooling to room temperature under the atmosphere of argon or nitrogen;

(3j) and (4) carrying out steps (3 f) - (3 i) on the product obtained in the step (3 i), and repeating for 3 times.

(4) And (3) machining: and (4) processing through holes on the heat-resistant plate product obtained in the step (3) according to the design size, and processing the head of the bolt, the screw rod of the bolt and the external thread of the screw rod on the bolt product according to the design size.

(5) Installing a stud: firstly, smearing ceramic precursor slurry containing nano fibers on the surface of a bolt, smearing the ceramic precursor slurry containing the nano fibers on the inner surface of a through hole of a heat-resistant plate, and then penetrating the bolt through the through hole of the heat-resistant plate to connect the bolt with the heat-resistant plate; after installation, smearing ceramic precursor slurry containing nano fibers between the surface of the head of the bolt and the surface of the front part of the heat-resistant plate; the ceramic precursor slurry containing the nano-fibers is prepared from a ceramic precursor, a solvent and the nano-fibers according to the weight ratio of 10: 8: 3 is prepared by ball milling and even mixing; the ceramic precursor is polysiloxane; the solvent is toluene; the nano-fibers are nano SiC fibers; the ball milling time is 3h, and the ball milling speed is 300 r/min.

(6) Repeating dipping-curing-cracking: firstly, low-temperature cracking is carried out, the product obtained in the step (5) is subjected to the steps (3 a) to (3 d), and the steps are repeated for 4 times; and (4) then carrying out high-temperature cracking, namely, continuing to carry out the steps (3 f) - (3 i), repeating for 1 time, and filling ceramic precursor slurry between the head surface of the bolt in the through hole and the front surface of the heat-resistant plate during impregnation, wherein the ceramic precursor slurry is filled in a gap between the through hole and the bolt.

(7) Preparing a densified SiC matrix by CVI: in order to improve the matching strength of the bolt and the heat-resistant plate, the product obtained in the step (6) is used for preparing a SiC matrix by adopting a CVI (chemical vapor infiltration) technology, and tiny pores in the deep position of the joint of the bolt and the heat-resistant plate are sealed; the product is put into a chemical vapor infiltration furnace, a strong convection CVI technology is adopted, trichlorosilane is taken as a precursor, hydrogen is taken as a carrier gas and a reducing gas, argon is taken as a diluent gas, the deposition temperature is 1000 ℃, the deposition time is 5 hours, the deposition pressure is 8kPa, the molar ratio of the reducing gas to the trichlorosilane is 8:1, the flow rate of the precursor is 1g/min, the flow rate of the diluting gas is 5L/min, the flow rate of the reducing gas is determined by the molar ratio of the reducing gas to a silicon source, and the flow rate of the carrier gas is 250 mL/min.

(8) CVD deposition of SiC coating: ultrasonically cleaning and drying the product obtained in the step (7) by using ethanol, coating a screw rod of a bolt extending out of a through hole of the heat-resistant plate by using carbon paper, then putting the product into a chemical vapor deposition furnace, taking trichlorosilane as a precursor, hydrogen as a carrier gas and a reducing gas, argon as a diluting gas, setting the deposition temperature of the chemical vapor deposition to 1300 ℃, the deposition time to 80 hours, the deposition pressure to 1kPa, the molar ratio of the reducing hydrogen to the trichlorosilane to 20:1, the flow rate of the precursor to 1g/min, the flow rate of the diluting gas to 2L/min, the flow rate of the reducing gas to be determined by the molar ratio of the reducing gas to a silicon source, the flow rate of the carrier gas to be 100mL/min, preparing a SiC coating on the surface of the product by chemical vapor deposition, improving the oxidation resistance and the wear resistance of the component, and then removing the carbon paper to obtain the heat-resistant plate, the density of the obtained product is 1.98g/cm³。

The samples of the ceramic matrix composite heat-resistant plates and the bolt parts obtained in examples 1 to 3 were cut out, and the properties of the cut-out samples were measured, and the results are shown in Table 1.

TABLE 1 Properties of the product samples