Rapid preparation method of large-size frame-like C-SiC ceramic-based component

Abstract

The invention discloses a rapid preparation method of a large-size frame-like C-SiC ceramic-based component. The rapid preparation method comprises the following steps: step S1, carbon cloth interface layer deposition and high-temperature treatment; s2, a forming mold is prepared; s3, laying and forming the prefabricated body; s4, integrally sewing the prefabricated body; s5, the sewn large-size frame prefabricated body and the inner mold are combined into the outer mold; s6, half mold stripping and PCS dipping curing treatment are carried out; s7, full mold removal and PCS cracking treatment are carried out; step S8, depositing a CVI silicon carbide substrate; step S9, finish machining; s10, CVI silicon carbide matrix deposition is continued; obtaining a ceramic-based large-size frame component; according to the method, after the mold is removed, mold-free cracking and CVI-SiC matrix deposition are carried out, uniform deposition of an interface layer and a matrix of a large-size frame type C / SiC composite material product with any wall thickness is achieved, and the bonding strength of fibers and an interface, the matrix deposition efficiency and the component size precision are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of large-size frame-type C-SiC ceramic substrate components, and more specifically to a rapid fabrication method for large-size frame-type C-SiC ceramic substrate components. Background Technology

[0002] C / SiC ceramic matrix composites, with their high temperature resistance (>1600℃), low density (2.0-2.5 g / cm³), high specific strength (>500 MPa), and excellent thermal shock resistance, have become the core choice for components in extreme environments in aerospace, energy, and other fields. Frame structures, due to their lightweight design principles, often employ complex geometries such as trusses and grids, placing extremely high demands on the shape adaptability, internal uniformity, and interfacial bonding strength of the fabrication process. The process must be able to accommodate the complex structural forming while ensuring consistent material properties.

[0003] Currently, prefabricated large-size frame products (especially complex structures with multiple cavities) mainly include two-dimensional carbon cloth lay-up and three-dimensional woven prefabricated bodies. Both adopt pure CVI process and use mold shaping. The preparation steps are as follows: (1) Lay / weave carbon cloth on the mold for shaping; (2) Deposit interface layer and high temperature treatment on the prefabricated body with inner and outer molds; (3) Low density stage: Deposit SiC substrate with full mold or inner mold for 2 to 3 furnaces; (4) Medium density stage: Remove full mold and deposit substrate for 4 to 5 furnaces; (5) Fine processing; (6) High density stage: Deposit for 3 to 4 furnaces to the final density.

[0004] The molding process mainly faces the following key issues: 1. Poor uniformity of interface layer deposition: The preform is blocked by the mold, which can easily lead to insufficient penetration of the deposition gas, affecting the uniformity of the interface layer deposition between the carbon cloth layers. 2. Poor matrix deposition efficiency and corner deposition effect: In the traditional molding method, the preform is relatively soft in the early stage (first 4 furnaces) of CVI matrix deposition, and a full mold or half mold is required. The mold blockage affects the deposition efficiency and the deposition uniformity at the corners of the frame components, thus affecting its overall strength. 3. Long preparation cycle: The traditional forming method is a pure CVI process, which is suitable for the preparation of components with a wall thickness ≤ 4mm. For components with thicker walls or larger dimensions, the preparation cycle is long (about 10 to 12 furnace cycles) and the cost is high. 4. Poor dimensional accuracy: Due to the large size of the components and the uneven deposition of the inner / outer substrate caused by the mold in the early stage, the components are prone to deformation during the deposition process after the mold is removed. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides a rapid fabrication method for large-size frame-type C-SiC ceramic substrate components, solving the problem of deposition uniformity issues caused by mold deposition in existing large-size frame-type products.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A rapid fabrication method for large-size frame-type C-SiC ceramic matrix components is provided, comprising the following steps: Step S1: Carbon cloth interface layer deposition and high-temperature treatment; carbon fibers are arranged in a CVI deposition furnace, and a pyrolytic carbon interface layer is deposited on the surface. After deposition, the deposited carbon fibers are arranged in a high-temperature furnace and subjected to high-temperature treatment under an inert atmosphere. Step S2: Prepare the molding mold; prepare the inner mold, outer mold, upper mold and lower mold for the preform respectively; Step S3: Preform layup; The carbon fiber cloth obtained in step S1 is laid layer by layer on the inner mold to form a large-size frame preform. Step S4: Prefabricated body assembly; 3K carbon fiber thread is used to sew the large-size frame prefabricated body as a whole. Step S5: Insert the sewn large-size frame prefabricated body and the inner mold into the outer mold, so that the gap between the outer mold and the inner mold is less than 0.05mm; Step S6: Demolding and PCS impregnation and curing treatment are performed on the large-size frame preform from step S5. Step S7: Perform full demolding and PCS pyrolysis treatment on the large-size frame prefabricated body from step S6; Step S8: Perform CVI silicon carbide substrate deposition on the large-size frame preform from step S7. Step S9: Perform finishing on the inner and outer surfaces of the large-size frame prefabricated body from step S7 to remove machining and edge-locking allowances; Step S10: Continue CVI silicon carbide substrate deposition; place the finely processed large-size frame preform into the CVI deposition furnace and perform 1 to 2 cycles of silicon carbide substrate deposition. During the deposition process, change the placement of the components by flipping them over until the product density is ≥2.0 g / cm³, thereby obtaining a ceramic-based large-size frame component.

[0007] This invention first deposits an interface layer on carbon fiber cloth, then shapes the preform using a mold and cures it with PIP, and finally removes the mold to perform moldless pyrolysis and CVI-SiC matrix deposition. This achieves uniform deposition of the interface layer and matrix in large-size, arbitrary-wall-thickness frame-type C / SiC composite material products, significantly improving the bonding strength between the fiber and the interface, matrix deposition efficiency, and component dimensional accuracy.

[0008] Furthermore, the pyrolytic carbon interface layer in step S1 is 50–500 nm.

[0009] Furthermore, the high-temperature treatment method in step S1 is as follows: the heating rate is 5-10℃ / min, the temperature is raised to 1800-2000℃ and then kept at that temperature for 2-4 hours, and then naturally cooled to room temperature.

[0010] Furthermore, the preform layup method in step S3 includes: Step S31, Laying up a single box-shaped preform: The carbon fiber cloth obtained in step S1 is laid up layer by layer on multiple sub-molds of the inner mold. Solid adhesive is used to fix the layers during the laying process to form multiple box-shaped preforms. Step S32, Multi-box splicing and positioning: Connect and position multiple sub-molds to make the spacing between adjacent precast box bodies consistent after splicing; Step S33: Laying out the outer prefabricated body; On the outside of the multiple assembled box-shaped prefabricated bodies, carbon fiber cloth is laid layer by layer to finally form a large-size frame prefabricated body.

[0011] Furthermore, the method for demolding and PCS impregnation and curing in step S6 is as follows: Step S61, Demolding: Remove the outer mold of the large-size frame preform; Step S62, PCS impregnation: The large-size frame preform after demolding is impregnated by atmospheric pressure casting for 2-6 hours. The preform is turned over every 0.5 hours to ensure that the PCS fully penetrates into the pores of the preform. Step S63, Mold Closure: After impregnation, close the outer mold into place. Step S64, Curing: Curing is performed with the inner and outer molds in place; the curing temperature is 120~200℃ and held for 1~3 hours, the heating rate is 2℃ / min, and the curing pressure is 0.2-0.5MPa.

[0012] Furthermore, the demolding and PCS pyrolysis process in step S7 is as follows: after curing, the inner and outer molds of the preform are removed; the large-size frame preform is placed in a pyrolysis furnace and pyrolyzed under an inert atmosphere to convert PCS into SiC.

[0013] Furthermore, the pyrolysis temperature rise curve during the PCS pyrolysis treatment process is as follows: from room temperature to 300℃, heating rate 3℃ / min, holding for 1h; from 300℃ to 800℃, heating rate 3℃ / min, holding for 1h; from 800℃ to 1100℃, heating rate 3℃ / min, holding for 4h.

[0014] Furthermore, the CVI silicon carbide substrate deposition process in step S8 is as follows: remove all molds, place the pyrolyzed large-size frame preform into the CVI deposition furnace, and perform multiple batches of silicon carbide substrate deposition.

[0015] Furthermore, the density of the large-size prefabricated frame is expected to be 1.4~1.5 g / cm³. 3 During this process, the sewing fibers in the cavity of the large-size prefabricated frame are removed; during the deposition process, the placement of the components is changed by flipping them over to ensure uniform deposition on all sides until the product density reaches 1.60~1.80 g / cm³.

[0016] This invention discloses a rapid fabrication method for large-size frame-type C-SiC ceramic matrix components, the advantages of which are: 1. This invention breaks through the limitations of traditional PyC interface layer deposition with a mold. First, an interface layer is deposited on carbon fiber cloth, and then a preform is shaped by a mold to achieve uniform deposition of the interface layer and the matrix of large-size frame-type C / SiC composite material products with arbitrary wall thickness, which greatly improves the bonding strength between the fiber and the interface.

[0017] 2. This invention introduces the PIP process to determine the size of the components. After the interface layer is prepared, PCS is impregnated and cured to ensure that the large-size frame prefabricated body has a certain dimensional accuracy and rigidity before demolding. This solves the problem of traditional molding methods where early demolding affects the substrate deposition efficiency, and premature demolding easily leads to deformation, thereby improving the dimensional accuracy of the components.

[0018] 3. The present invention uses a moldless deposition substrate to improve the deposition uniformity of SiC substrate at the corners and inside of the component, while improving the deposition efficiency of the overall molded component and reducing costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the mold-closing structure of a large-size frame-type C-SiC ceramic-based component according to the present invention.

[0020] Figure 2 This is a schematic diagram of the structure of the box-shaped prefabricated body of the present invention.

[0021] Figure 3 This is a structural schematic diagram of the large-size frame prefabricated body of the present invention.

[0022] Figure 4 This is a schematic diagram of the structure of the inner mold of the present invention.

[0023] Figure 5 This is an exploded structural diagram of the inner mold of the present invention.

[0024] Figure 6 This is a schematic diagram of the structure of the outer mold of the present invention.

[0025] Figure 7 This is a schematic diagram of the upper and lower molds of the present invention.

[0026] Among them, 1. Inner mold; 2. Outer mold; 3. Upper mold; 4. Lower mold; 5. Box-shaped precast body; 6. Large-size frame precast body. Detailed Implementation The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0027] Example 1 refer to Figures 1-7 This embodiment provides a rapid preparation method for large-size frame-type C-SiC ceramic matrix components. Its purpose is to solve the problem of the deposition uniformity affected by the deposition of existing large-size frame-type products with molds. The specific structure of this embodiment will be described in detail below.

[0028] A rapid fabrication method for large-size frame-type C-SiC ceramic matrix components includes the following steps: Step S1: Carbon cloth interface layer deposition and high-temperature treatment; carbon fibers are arranged in a CVI deposition furnace, and a pyrolytic carbon interface layer is deposited on the surface. After deposition, the deposited carbon fibers are arranged in a high-temperature furnace and subjected to high-temperature treatment under an inert atmosphere. Specifically, the pyrolytic carbon interface layer in step S1 is 50–500 nm.

[0029] The high-temperature treatment method in step S1 is as follows: the heating rate is 5-10℃ / min, the temperature is raised to 1800-2000℃ and then kept at that temperature for 2-4 hours, and then naturally cooled to room temperature.

[0030] In this embodiment, 3K carbon fiber cloth is selected, and the carbon fiber is directly arranged in the CVI deposition furnace without any mold constraint. The CVI process is used to deposit a pyrolytic carbon (PyC) interface layer on its surface, requiring an interface layer thickness of 50-500 nm.

[0031] The 3K carbon fibers after the PyC interface layer is deposited are then placed in a high-temperature furnace and subjected to high-temperature treatment under an inert atmosphere (argon). The heating rate is 5-10℃ / min. After heating to 1800-2000℃, the temperature is held for 2-4 hours and then allowed to cool naturally to room temperature to improve the graphitization degree of the carbon fiber cloth and enhance its mechanical properties and temperature resistance.

[0032] This breakthrough overcomes the limitations of traditional PyC interface layer deposition with a mold. First, an interface layer is deposited on carbon fiber cloth, and then a mold is used for shaping, achieving uniform deposition of the interface layer in large-size, arbitrary-wall-thickness frame-type C / SiC composite material products, thus improving the bonding performance between the fiber and the matrix.

[0033] Step S2: Prepare the molding molds; prepare the inner mold 1, outer mold 2, upper mold 3 and lower mold 4 respectively to act on the preform; In this embodiment, the inner mold 1 is divided into multiple sub-molds, five in this embodiment. Each sub-mold is divided into upper and lower halves, which are connected and positioned by a self-locking mechanism. Multiple sub-molds are assembled to form the inner mold 1. The outer surface of the inner mold 1 matches the inner cavity shape of the large-size frame prefabricated body 6, and the sub-molds are provided with sewing grooves. The width of the sewing grooves is 3mm, and the distance between the grooves is 5mm, ensuring that the sewing thread only adheres to the prefabricated body and does not have a connection with the mold during subsequent sewing. Outer mold 2: The outer mold 2 is designed in multiple parts to match the outer contour shape of the large-size frame prefabricated body 6. After the mold is closed, it can completely wrap the outer prefabricated body and achieve overall size constraint. Upper mold 3 and lower mold 4: Upper mold 3 and lower mold 4 are integral structures that match the upper and lower outer contours of the large frame and have ventilation windows to reduce airflow.

[0034] Design of large-size prefabricated frame 6: The overall shape of the parts is left with a machining allowance of 0.5 mm and a seam allowance of 10 mm.

[0035] Step S3: Preform layup; The carbon fiber cloth obtained in step S1 is laid layer by layer on the inner mold 1 to form a large-size frame preform 6. Specifically, the preform layup method in step S3 includes: Step S31, Laying up a single box-shaped preform 5: The carbon fiber cloth obtained in step S1 is laid up layer by layer on multiple sub-molds of the inner mold. During the laying process, the layers are bonded and fixed with solid glue to form multiple box-shaped preforms 5. The cut is placed on the top and bottom surfaces, and the layer thickness is controlled to 4mm (the number of layers is adjusted according to the thickness of the carbon cloth to ensure uniform overall wall thickness).

[0036] Step S32, Multi-box splicing and positioning: Multiple sub-molds are connected and positioned by bolts and positioning pins between each sub-mold, and the spacing between adjacent box-shaped prefabricated bodies 5 after splicing is consistent; Step S33: Laying out the outer prefabricated body; On the outside of the multiple box-shaped prefabricated bodies 5 that have been spliced, the carbon fiber cloth obtained in step S1 is laid layer by layer, with the cuts placed on the four sides, the height of the cuts staggered layer by layer, and the thickness of the layup controlled at 2.5mm, finally forming a large-size frame prefabricated body 6 with an overall wall thickness of 6.5mm.

[0037] Step S4: Prefabricated body assembly; 3K carbon fiber thread is used to sew the large-size frame prefabricated body 6 as a whole. In this embodiment, 3K carbon fiber thread containing sizing agent (epoxy resin sizing agent, solid content 10%-40%) is used to sew the large-size frame preform 6 formed in step S3 as a whole; the stitch spacing is set to 5mm×5mm (both horizontal and vertical stitch spacing is 5mm). During the sewing process, it is ensured that the sewing thread follows the sewing groove of the inner mold 1 and does not have a connection with the inner mold 1 or the outer mold 2, so as to avoid the sewing thread sticking to the mold and affecting demolding.

[0038] Step S5: Insert the sewn large-size frame prefabricated body 6 and the inner mold 1 into the outer mold 2, so that the gap between the outer mold 2 and the inner mold 1 is less than 0.05mm; Step S6: Demolding and PCS impregnation and curing treatment are performed on the large-size frame prefabricated body 6 from step S5. Specifically, the demolding and PCS (hyperbranched polysilane) impregnation and curing treatment method in step S6 is as follows: Step S61, Demolding: Remove the outer mold 2, upper mold 3 and lower mold 4 of the large-size frame preform 6; Step S62, PCS impregnation: The large-size frame preform 6 after demolding is impregnated by atmospheric pressure casting for 2-6 hours. The preform is turned over every 0.5 hours to ensure that the PCS fully penetrates into the pores of the preform. Step S63, Mold Closure: After impregnation, close the upper mold 3 and the lower mold 4; the upper mold 3 and the lower mold 4 are connected by bolts and positioned by locating pins; Step S64, Curing: Curing is performed with the inner mold 1, outer mold 2, upper mold 3 and lower mold 4 in place; the curing temperature is 120~200℃ and the holding time is 1~3h, the heating rate is 2℃ / min, and the curing pressure is 0.2-0.5MPa.

[0039] In this embodiment, the impregnation solution in step S62 is a polycarbosilane (PCS) system without added dicumyl peroxide (DCP) (viscosity of 500-1000 mPa at 25°C). s).

[0040] Meanwhile, the large-size frame precast body 6 is constrained by the inner mold 1, outer mold 2, upper mold 3 and lower mold 4 to ensure that the outer dimensions of the large-size frame precast body 6 are fixed (dimensional deviation ≤ 0.15mm).

[0041] Step S7: Perform full demolding and PCS pyrolysis treatment on the large-size frame prefabricated body 6 from step S6; Specifically, the demolding and PCS pyrolysis process in step S7 is as follows: After curing, the inner mold 1, outer mold 2, upper mold 3 and lower mold 4 of the preform are removed; the large-size frame preform 6 is placed in a pyrolysis furnace and pyrolyzed under an inert atmosphere to convert PCS into SiC.

[0042] The pyrolysis temperature rise curves during the PCS pyrolysis process are as follows: from room temperature to 300℃ at a rate of 3℃ / min, held for 1 hour; from 300℃ to 800℃ at a rate of 3℃ / min, held for 1 hour; from 800℃ to 1100℃ at a rate of 3℃ / min, held for 4 hours; to ensure that the SiC conversion rate in the large-size frame preform 6 after pyrolysis is ≥75%.

[0043] Step S8: Perform CVI silicon carbide substrate deposition on the large-size frame preform 6 from step S7. Specifically, the CVI silicon carbide substrate deposition process in step S8 is as follows: remove all molds, place the large-size frame preform 6 after pyrolysis into the CVI deposition furnace, and perform multiple batches of silicon carbide substrate deposition.

[0044] The density of the large-size precast frame 6 is expected to be 1.4~1.5 g / cm³. 3 During this process, the sewing fibers in the inner cavity of the large-size precast frame 6 are removed; during the deposition process, the placement of the components is changed by flipping them over to ensure uniform deposition on each surface until the product density reaches 1.60~1.80 g / cm³.

[0045] In this embodiment, the flipping operation is as follows: after each batch of deposition is completed (single batch deposition time 50-70 h), the preform is flipped (90° rotation) before the next batch of deposition is carried out to ensure uniform deposition on all surfaces of the preform and at the corners of the box shape.

[0046] Step S9, finishing; finish the inner and outer surfaces of the large-size frame prefabricated body 6 in step S7, and remove the machining and edge-locking allowances; Step S10: Continue CVI silicon carbide substrate deposition; place the finely processed large-size frame preform 6 into the CVI deposition furnace and perform 1 to 2 batches of silicon carbide substrate deposition. During the deposition process, change the placement of the component by flipping it over to ensure uniform deposition on each side until the product density is ≥2.0g / cm³, thereby obtaining a ceramic-based large-size frame component.

[0047] Although specific embodiments of the invention have been described in detail with reference to the accompanying drawings, this should not be construed as limiting the scope of protection of this patent. Various modifications and variations that can be made by a person skilled in the art without inventive effort within the scope described in the claims still fall within the scope of protection of this patent.

Claims

1. A rapid fabrication method for large-size frame-type C-SiC ceramic matrix components, characterized in that, Includes the following steps: Step S1: Carbon cloth interface layer deposition and high-temperature treatment; Carbon fibers are arranged in a CVI deposition furnace to deposit a pyrolytic carbon interface layer on the surface. After deposition, the deposited carbon fibers are arranged in a high-temperature furnace and subjected to high-temperature treatment under an inert atmosphere. Step S2: Prepare the molding mold; prepare the inner mold, outer mold, upper mold and lower mold for the preform respectively; Step S3: Preform layup; The carbon fiber cloth obtained in step S1 is laid layer by layer on the inner mold to form a large-size frame preform. Step S4: Prefabricated body assembly; 3K carbon fiber thread is used to sew the large-size frame prefabricated body as a whole. Step S5: Insert the sewn large-size frame prefabricated body and the inner mold into the outer mold, so that the gap between the outer mold and the inner mold is less than 0.05mm; Step S6: Demolding and PCS impregnation and curing treatment are performed on the large-size frame preform from step S5. Step S7: Perform full demolding and PCS pyrolysis treatment on the large-size frame prefabricated body from step S6; Step S8: Perform CVI silicon carbide substrate deposition on the large-size frame preform from step S7. Step S9: Perform finishing on the inner and outer surfaces of the large-size frame prefabricated body from step S7 to remove machining and edge-locking allowances; Step S10: Continue CVI silicon carbide substrate deposition; place the finely processed large-size frame preform into the CVI deposition furnace and perform 1 to 2 cycles of silicon carbide substrate deposition. During the deposition process, change the placement of the components by flipping them over until the product density is ≥2.0 g / cm³, thereby obtaining a ceramic-based large-size frame component.

2. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 1, characterized in that: The pyrolytic carbon interface layer in step S1 is 50–500 nm.

3. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 1, characterized in that, The high-temperature treatment method in step S1 is as follows: the heating rate is 5-10℃ / min, the temperature is raised to 1800-2000℃ and then kept at that temperature for 2-4 hours, and then naturally cooled to room temperature.

4. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 1, characterized in that, The preform layup method in step S3 includes: Step S31, Laying up a single box-shaped preform: The carbon fiber cloth obtained in step S1 is laid up layer by layer on multiple sub-molds of the inner mold. Solid adhesive is used to fix the layers during the laying process to form multiple box-shaped preforms. Step S32, Multi-box splicing and positioning: Connect and position multiple sub-molds to ensure that the spacing between adjacent box-shaped prefabricated bodies is consistent after splicing; Step S33: Laying out the outer prefabricated body; On the outside of the multiple assembled box-shaped prefabricated bodies, carbon fiber cloth is laid layer by layer to finally form a large-size frame prefabricated body.

5. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 1, characterized in that, The method for demolding and PCS impregnation and curing in step S6 is as follows: Step S61, Demolding: Remove the outer mold of the large-size frame preform; Step S62, PCS impregnation: The large-size frame preform after demolding is impregnated by atmospheric pressure casting for 2-6 hours. The preform is turned over every 0.5 hours to ensure that the PCS fully penetrates into the pores of the preform. Step S63, Mold Closure: After impregnation, close the outer mold into place; Step S64, Curing: Curing is performed while the inner and outer molds are in place; The curing temperature is 120~200℃, and the holding time is 1~3h. The heating rate is 2℃ / min, and the curing pressure is 0.2-0.5MPa.

6. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 1, characterized in that, The process of removing the mold and pyrolysis of PCS in step S7 is as follows: After curing, the inner and outer molds of the preform are removed; the large-size frame preform is placed in a pyrolysis furnace and pyrolyzed under an inert atmosphere to convert PCS into SiC.

7. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 6, characterized in that, The pyrolysis temperature rise curves during the PCS pyrolysis process are as follows: from room temperature to 300℃ at a rate of 3℃ / min, and held for 1 hour; from 300℃ to 800℃ at a rate of 3℃ / min, and held for 1 hour; from 800℃ to 1100℃ at a rate of 3℃ / min, and held for 4 hours.

8. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 1, characterized in that, The CVI silicon carbide substrate deposition process in step S8 is as follows: remove all molds, place the pyrolyzed large-size frame preform into the CVI deposition furnace, and perform multiple batches of silicon carbide substrate deposition.

9. The rapid fabrication method for large-size frame-type C-SiC ceramic matrix components according to claim 8, characterized in that: The density of the large-size precast frame is expected to be 1.4~1.5 g / cm³. 3 At the same time, remove the sewn fibers from the cavity of the large-size frame prefabrication; during the deposition process, change the placement of the components by flipping them over until the product density reaches 1.60~1.80 g / cm³.

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