A method of manufacturing a ceramic matrix composite blade

Abstract

The application provides a preparation method of a ceramic matrix composite blade, which can solve the problems of the existing preparation method of the ceramic matrix composite blade, such as small proportion of fiber continuity of the obtained blade, and poor mechanical properties such as strength and stiffness of the blade. The method comprises the following steps: establishing a middle surface; designing an upper surface and a lower surface of a blade body and respectively reserving machining allowances in the thickness direction, reserving machining allowances on both sides and the front end of the obtained blade body intermediate body to obtain a blade body preform; extending to the tenon direction based on the middle surface to form an extension surface, designing an upper surface and a lower surface of the tenon and respectively reserving machining allowances in the thickness direction, reserving machining allowances on both sides of the obtained tenon intermediate body to obtain a tenon preform, and constituting a blade preform; manufacturing a shaping mold; shaping after determining the layer number and cutting size of blade body fiber cloth and tenon fiber cloth; sewing and locking edges; depositing; removing the shaping mold, and then machining and depositing to obtain the blade.

Description

Technical Field

[0001] This invention relates to a method for preparing aero-engine components, specifically a method for preparing ceramic matrix composite blades. Background Technology

[0002] With the rapid development of aerospace technology, the performance requirements for aero-engines are increasing. As one of the key components of aero-engines, blades need to withstand large loads in harsh environments such as high temperature and high pressure, and also need to maintain high stability in such harsh environments. Therefore, blades need to have high strength and high stiffness. The strength and stiffness of blades mainly depend on the proportion of fiber continuity in their fabrication process. This requires that when designing blade preforms, not only should the design structure, shape, size, layup method, ease of shaping, damage and defects of the preform and allowance for processing, thermal expansion matching between materials and tooling, deposition efficiency and loss rate be fully considered, but also the proportion of fiber continuity should be fully taken into account. Figure 1 This is a schematic diagram of the three-dimensional structure of an existing blade, which includes a blade body 02 and a tenon 03. Currently, ceramic matrix composite blades are typically fabricated by first preparing the blade body 02 and the tenon 03 separately, and then riveting them together. However, this method has the problem that the resulting blade has a low fiber continuity ratio, resulting in poor mechanical properties such as strength and stiffness. Summary of the Invention

[0003] The purpose of this invention is to solve the technical problems of existing methods for preparing ceramic matrix composite blades, such as the low proportion of continuous fiber in the blades and poor mechanical properties such as strength and stiffness, and to provide a method for preparing ceramic matrix composite blades.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A method for preparing a ceramic matrix composite blade, the blade comprising a blade body and a tenon; the tenon being connected to the tail end of the blade body; characterized in that it includes the following steps:

[0006] Step 1: Design the blade preform

[0007] Step 1.1: Establish the mid-surface based on the curvature of the upper and lower surfaces of the blade;

[0008] Step 1.2: Based on the intermediate surface, design the upper surface and lower surface of the blade. Then, reserve a machining allowance of 0.5 to 1.0 mm in the thickness direction of the upper surface and lower surface of the blade to obtain the intermediate body of the blade. Reserve a machining allowance of 5.0 to 10 mm on both sides and the front end of the intermediate body of the blade to obtain the blade preform.

[0009] Step 1.3: Based on the intermediate surface, extend it 5.0-10mm beyond the tenon tail to form an extension surface. Then, based on the extension surface, design the upper and lower tenon profiles. Leave a machining allowance of 0.5-1.0mm in the thickness direction of both the upper and lower tenon profiles to obtain the tenon intermediate body. Leave a machining allowance of 5.0-10mm on both sides of the tenon intermediate body to obtain the tenon prefabricated body. The tenon prefabricated body and the blade prefabricated body constitute the blade prefabricated body.

[0010] Step 2: Fabricate a shaping mold based on the blade preform;

[0011] Step 3: Determine the number of layers of blade fiber cloth and tenon fiber cloth according to the thickness of the blade preform and tenon preform respectively; determine the cutting size of blade fiber cloth and tenon fiber cloth according to the size of blade preform and tenon preform respectively, and cut them accordingly.

[0012] Step 4: Using the shaping mold and the blade fiber cloth and tenon fiber cloth cut in Step 3, shape the blade preform.

[0013] Step 5: Sew and lock the edges of the shaped blade preform;

[0014] Step 6: The preformed blade after edge locking is subjected to interface layer deposition and silicon carbide substrate layer deposition in sequence using chemical vapor deposition.

[0015] Step 7: Remove the shaping mold, first machine the preform of the blade after deposition treatment, and then perform silicon carbide matrix deposition treatment to obtain ceramic matrix composite blade.

[0016] Furthermore, in step 2, the shaping mold includes an upper mold, a lower mold, and at least two fastening components;

[0017] The mounting surface of the upper mold includes a first arc-shaped convex surface and a second arc-shaped convex surface. The first arc-shaped convex surface is adapted to the upper surface of the tenon preform, and the second arc-shaped convex surface is adapted to the upper surface of the blade preform. A first sewing hole is provided on the mounting surface of the upper mold. A first positioning hole is provided at two corner positions of the upper mold.

[0018] The mounting surface of the lower mold includes a first arc-shaped concave surface and a second arc-shaped concave surface. The first arc-shaped concave surface is adapted to the lower surface of the tenon preform, and the second arc-shaped concave surface is adapted to the lower surface of the blade preform. The mounting surface of the lower mold is provided with a second sewing hole corresponding to the first sewing hole. The lower mold is provided with a second positioning hole corresponding to the first positioning hole.

[0019] The fastening assembly is used to secure the upper and lower molds after mold closing;

[0020] Step 4 specifically includes the following steps:

[0021] Step 4.1: Lay the cut blade fiber cloth from step 3 onto the second arc-shaped convex surface, then lay the cut tenon fiber cloth from step 3 onto the first arc-shaped convex surface until it is flush with the outermost blade fiber cloth. Finally, lay the remaining tenon fiber cloth onto the first arc-shaped concave surface to obtain the stacked upper and lower molds.

[0022] Alternatively, the blade fiber cloth cut in step 3 is layered and laid on the second arc-shaped concave surface, and then the tenon fiber cloth cut in step 3 is layered and laid on the first arc-shaped concave surface until it is flush with the outermost blade fiber cloth. Finally, the remaining tenon fiber cloth is layered and laid on the first arc-shaped convex surface to obtain the layered upper mold and lower mold.

[0023] Step 4.2: Close the stacked upper and lower molds and fasten them with fastening components to obtain the shaped blade preform;

[0024] Step 4.3: Use a 0.15mm feeler gauge to check the fitting gap between the shaped blade preform and the upper and lower molds. If the fitting gap is ≥0.15mm, proceed to step 4.4; if the fitting gap is <0.15mm, proceed to step 5.

[0025] Step 4.4: Disassemble the fastening components, add re-cut blade fiber cloth and tenon fiber cloth to the outermost blade fiber cloth and tenon fiber cloth, and return to step 4.2.

[0026] Furthermore, in step 2, the diameter of the first sewing hole and the second sewing hole are both 3-5 mm, and the distance between adjacent first sewing holes and adjacent second sewing holes is both 5-8 mm.

[0027] The mounting surfaces of both the upper and lower molds are of equal wall thickness.

[0028] Furthermore, in step 3, the cutting dimensions of the blade fiber cloth and the tenon fiber cloth are reserved with a 6-10mm overlock allowance.

[0029] Furthermore, step 5 specifically includes:

[0030] The shaped blade preform is sewn together and then edged; the edge stitching needs to meet the following conditions: no needle slippage and needle spacing ≤ 3mm.

[0031] Furthermore, step 6 specifically includes the following steps:

[0032] Step 6.1: Place the edge-locked blade preform in a chemical vapor deposition furnace, and then heat it to 650-1000℃ under a furnace pressure of 50-1000Pa. After holding it at this temperature for 1-3 hours, argon, hydrogen, ammonia and boron trichloride gas are introduced sequentially for deposition until a blade preform with a boron nitride interface layer with a thickness of 150-750nm is obtained. Continue to hold it at this temperature for 1-3 hours, and then cool it to room temperature.

[0033] Alternatively, the preformed blade with the edge locked is placed in a chemical vapor deposition furnace, and then heated to 500-1000℃ under a furnace pressure of 10-70Pa. After holding at this temperature for 1-3 hours, argon and propylene gases are introduced sequentially for deposition until a preformed blade with a pyrolytic carbon interface layer of 100-350nm thickness is obtained. The temperature is then maintained for another 1-3 hours, and then cooled to room temperature.

[0034] Step 6.2: Under a furnace pressure of 200-5000 Pa, heat to 900-1200℃ and hold for 1-2 hours. Then, introduce a mixed gas of trichloromethylsilane, hydrogen, and argon, with a flow rate ratio of 1-10:10-12:10-30, to deposit the blade preform obtained in Step 6.1 until a particle size distribution of 1.7-1.8 g / cm³ is achieved. 3 The blade preform with high density silicon carbide matrix layer is kept at a constant temperature for 1-3 hours, and then cooled to room temperature.

[0035] Furthermore, step 7 specifically includes:

[0036] After removing the upper and lower molds, the blade preform obtained in step 6.2 is first machined, and then silicon carbide substrate is deposited according to the deposition method in step 6.2 until the density of the silicon carbide substrate layer is >2.4 g / cm³. 3 To obtain ceramic matrix composite blades.

[0037] Furthermore, in step 2, each of the fastening components includes two pressure bars, two double-ended bolts, and four nuts;

[0038] The two pressure strips are respectively used to abut against the opposite surfaces of the mounting surfaces of the upper mold and the lower mold.

[0039] The two double-ended bolts are used to pass through both ends of the two pressure strips and are secured by four nuts.

[0040] Furthermore, the shaping mold is made of a high-temperature resistant material.

[0041] Furthermore, the shaping mold is made of high-strength fine graphite, high-purity graphite, or electrode graphite.

[0042] The beneficial effects of this invention are:

[0043] 1. This invention provides a method for preparing ceramic matrix composite blades. By establishing corresponding designs for the mid-plane and extension plane of the blade preform and the tenon preform, the blade preform design is obtained. This method can effectively increase the proportion of continuous fibers on the mid-plane and extension plane of the blade, and can simultaneously ensure that the fibers at the tenon and blade connection positions are continuous, thereby improving the mechanical properties of the blade and ensuring that it has high strength and stiffness.

[0044] 2. By detecting the bonding gap, rationally setting the hole diameter and hole spacing parameters of the first and second sewing holes, and combining them with subsequent edge-locking operations, this invention can effectively prevent delamination defects and significantly improve the final mechanical properties of the blade.

[0045] 3. The shaping mold in this invention has a simple structure and is easy to operate. Since the mounting surfaces of the upper mold and the lower mold are both of equal wall thickness, under the premise of efficient shaping of the blade preform, the deposition efficiency and deposition uniformity in the subsequent preparation process can be effectively improved, the preparation cycle can be shortened, the economic cost can be reduced, and the mechanical properties of the blade preform can be effectively improved. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the three-dimensional structure of an existing blade;

[0047] Figure 2 This is a schematic diagram of the structure of the blade preform in step 1 of an embodiment of the method for preparing a ceramic matrix composite blade of the present invention;

[0048] Figure 3 yes Figure 2 A three-dimensional structural diagram of the precast mid-section body;

[0049] Figure 4 This is a three-dimensional structural diagram of the shaping mold and the shaped blade preform in step 4 of the present invention.

[0050] Figure 5 This is a three-dimensional structural diagram of the shaping mold and the shaped blade preform from another perspective in step 4 of the present invention.

[0051] Figure 6 This is a three-dimensional structural diagram of the shaping mold and the shaped blade preform from another perspective in step 4 of the present invention.

[0052] Explanation of reference numerals in the attached figures:

[0053] 01-Blade, 02-Blade body, 03-Tenon, 3-Upper mold, 4-Lower mold, 5-Nut, 6-Pressure strip, 7-Double-ended bolt, 8-Fastening component, 9-First sewing hole, 10-First positioning hole, 11-Second sewing hole, 12-Second positioning hole, 21-Tenon preform, 22-Blade preform, 23-Blade body preform, 24-Middle surface. Detailed Implementation

[0054] A method for preparing ceramic matrix composite blades, such as... Figures 1-3 As shown, the blade 01 includes a blade body 02 and a tenon 03, with the tenon 03 connected to the tail end of the blade body 02. The manufacturing method includes the following steps:

[0055] Step 1: Design the blade preform 22

[0056] Step 1.1: Establish the middle surface 24 based on the curvature of the upper and lower surfaces of the blade 02;

[0057] Step 1.2: Based on the intermediate surface 24, design the upper surface and lower surface of the blade. Then, reserve a machining allowance of 0.5-1.0 mm in the thickness direction of the upper surface and lower surface of the blade (0.5 mm machining allowance in this embodiment) to obtain the blade intermediate body. Reserve a machining allowance of 5.0-10 mm on both sides and the front end of the blade intermediate body (8 mm machining allowance in this embodiment) to obtain the blade preform 23.

[0058] Step 1.3: Based on the intermediate surface 24, extend it towards the tenon 03 to exceed the tail of the tenon 03 by 5.0-10mm (8mm machining allowance in this embodiment), forming an extension surface. Then, based on the extension surface, design the upper and lower tenon surfaces. Then, reserve 0.5-1.0mm machining allowance in the thickness direction of the upper and lower tenon surfaces respectively (0.5mm machining allowance in this embodiment), to obtain the tenon intermediate body. Reserve 5.0-10mm machining allowance on both sides of the tenon intermediate body (8mm machining allowance in this embodiment), to obtain the tenon prefabricated body 21. The tenon prefabricated body 21 and the blade prefabricated body 23 constitute the blade prefabricated body 22.

[0059] Step 2: Create a shaping mold based on the blade preform 22, such as... Figures 4-6As shown, the forming mold includes an upper mold 3, a lower mold 4, and two fastening components 8. Specifically, the mounting surface of the upper mold 3 includes a first arc-shaped convex surface and a second arc-shaped convex surface. The first arc-shaped convex surface is adapted to the upper surface of the tenon preform 21, and the second arc-shaped convex surface is adapted to the upper surface of the blade preform 23. A first sewing hole 9 is provided on the mounting surface of the upper mold 3, and first positioning holes 10 are provided at two corner positions of the upper mold 3. The mounting surface of the lower mold 4 includes a first arc-shaped concave surface and a second arc-shaped concave surface. The first arc-shaped concave surface is adapted to the lower surface of the tenon preform 21, and the second arc-shaped concave surface is adapted to the lower surface of the blade preform 23. A second sewing hole 11 corresponding to the first sewing hole 9 is provided on the mounting surface of the lower mold 4, and a second positioning hole 12 corresponding to the first positioning hole 10 is provided on the lower mold 4. The mounting surfaces of the upper mold 3 and the lower mold 4 are both surfaces with equal wall thickness. The diameter of the first sewing hole 9 and the second sewing hole 11 is 3-5 mm, and the distance between adjacent first sewing holes 9 and adjacent second sewing holes 11 is 5-8 mm.

[0060] Each fastening assembly 8 includes two pressure strips 6, two double-ended bolts 7, and four nuts 5. The two pressure strips 6 are respectively used to abut against the opposite surfaces of the mounting surfaces of the upper mold 3 and the lower mold 4. The two double-ended bolts 7 are respectively used to pass through both ends of the two pressure strips 6 and are fastened by the four nuts 5.

[0061] In this embodiment, the shaping mold is made of high-strength fine graphite. The diameter of both the first slit hole 9 and the second slit hole 11 is 3mm, and the distance between adjacent first slit holes 9 and adjacent second slit holes 11 is 5mm. In other embodiments, the shaping mold can be made of high-purity graphite or electrode graphite.

[0062] Step 3: Determine the number of layers of blade fiber cloth and tenon fiber cloth based on the thickness of the blade preform 23 and tenon preform 21, respectively; determine the cutting dimensions of the blade fiber cloth and tenon fiber cloth based on the dimensions of the blade preform 23 and tenon preform 21, and then cut them; a 6-10mm overlock allowance is reserved in the cutting dimensions of the blade fiber cloth and tenon fiber cloth to avoid delamination during subsequent preparation due to unsealed edges. In this embodiment, a 10mm overlock allowance is reserved.

[0063] It should be noted that, in other embodiments, the machining allowance reserved in steps 1.2 and 1.3, the hole diameter of the first sewing hole 9 and the second sewing hole 11 in step 2, the hole spacing between adjacent first sewing holes 9 and adjacent second sewing holes 11, and the edge-locking allowance reserved in step 3 can be flexibly adjusted.

[0064] Step 4: Shaping of blade preform 22

[0065] Step 4.1: Lay the cut blade fiber cloth from step 3 onto the second arc-shaped convex surface, then lay the cut tenon fiber cloth from step 3 onto the first arc-shaped convex surface until it is flush with the outermost blade fiber cloth. Finally, lay the remaining tenon fiber cloth onto the first arc-shaped concave surface to obtain the upper mold 3 and lower mold 4 after lamination.

[0066] In other embodiments, this step is specifically as follows: the blade fiber cloth cut in step 3 is layered and laid on the second arc-shaped concave surface, and then the tenon fiber cloth cut in step 3 is layered and laid on the first arc-shaped concave surface until it is flush with the outermost blade fiber cloth. Finally, the remaining tenon fiber cloth is layered and laid on the first arc-shaped convex surface to obtain the layered upper mold 3 and lower mold 4.

[0067] Step 4.2: Close the stacked upper mold 3 and lower mold 4, and secure them with fastening components 8 to obtain the shaped blade preform 22, as shown. Figures 4-6 As shown;

[0068] Step 4.3: Use a 0.15mm feeler gauge to check the fitting gap between the shaped blade preform 22 and the upper mold 3 and lower mold 4. If the fitting gap is ≥0.15mm, proceed to step 4.4; if the fitting gap is <0.15mm, proceed to step 5.

[0069] Step 4.4: Disassemble fastening assembly 8, add re-cut blade fiber cloth and tenon fiber cloth to the outermost blade fiber cloth and tenon fiber cloth, and return to step 4.2.

[0070] Step 5: The shaped blade preform 22 is sewn together. During the sewing process, the steel needle is perpendicular to the surface of the shaped mold. The sewn joint is left on the non-installation surface of the shaped mold. Then, the edge is locked. The edge locking needs to meet the following conditions: no needle slippage, and the needle spacing ≤ 3mm, in order to prevent defects such as delamination in the subsequent chemical vapor deposition process.

[0071] Step 6: The preformed blade 22 after edge locking is subjected to interface layer deposition and silicon carbide substrate layer deposition sequentially using chemical vapor deposition; specifically including the following steps:

[0072] Step 6.1: Place the edge-locked blade preform 22 in a chemical vapor deposition furnace, and then, under a furnace pressure of 50-1000 Pa, heat it to 650-1000℃ and hold it for 1-3 hours. Then, sequentially introduce argon, hydrogen, ammonia, and boron trichloride gas for deposition until a blade preform 22 with a boron nitride interface layer of 150-750 nm thickness is obtained. Continue to hold it for 1-3 hours, and then cool it to room temperature. In this embodiment, the furnace pressure is 850 Pa, the temperature is raised to 950℃, and held for 3 hours.

[0073] In other embodiments, this step specifically involves: placing the edge-locked blade preform 22 in a chemical vapor deposition furnace, then heating it to 500-1000℃ under a furnace pressure of 10-70 Pa, holding it at that temperature for 1-3 hours, and then sequentially introducing argon and propylene gases for deposition until a blade preform 22 with a pyrolytic carbon interface layer of 100-350 nm thickness is obtained, continuing to hold it at that temperature for 1-3 hours, and then cooling it to room temperature;

[0074] Step 6.2: Under a furnace pressure of 200-5000 Pa, heat to 900-1200℃ and hold for 1-2 hours. Then, introduce a mixed gas of trichloromethylsilane, hydrogen, and argon, with a flow rate ratio of 1-10:10-12:10-30, to deposit the blade preform 22 obtained in step 6.1 until a particle size of 1.7-1.8 g / cm³ is obtained. 3 The blade preform 22 with a high density silicon carbide substrate layer is kept at a constant temperature for 1-3 hours, and then cooled to room temperature. In this embodiment, the furnace pressure is 3000 Pa, the temperature is raised to 1100 °C, and held for 2 hours. The flow ratio of trichloromethylsilane, hydrogen, and argon is 1:10:10.

[0075] Step 7: Remove the upper mold 3 and lower mold 4. First, machine the blade preform 22 obtained in step 6.2, and then perform silicon carbide substrate deposition treatment according to the deposition method in step 6.2 until the density of the silicon carbide substrate layer is >2.4 g / cm³. 3 To obtain ceramic matrix composite blades.

[0076] It should be noted that the process parameters for the deposition treatment in step 6 are mature processes, and those skilled in the art can adjust them flexibly.

[0077] 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 should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for manufacturing a ceramic matrix composite blade, the blade (01) comprising a blade body (02) and a tenon (03); the tenon (03) is connected with the tail end of the blade body (02); characterized in that, The method comprises the following steps: Step 1, designing a blade preform (22) Step 1.1, establishing a middle surface (24) according to the upper surface curvature and the lower surface curvature of the blade body (02); Step 1.2, designing the upper surface and the lower surface of the blade body based on the middle surface (24), and then reserving a machining allowance of 0.5-1.0 mm in the thickness direction of the upper surface and the lower surface of the blade body to obtain a blade body intermediate body, and reserving a machining allowance of 5.0-10 mm on both sides and the front end of the blade body intermediate body to obtain a blade body preform (23); Step 1.3, extending the middle surface (24) to more than 5.0-10 mm of the tail of the tenon (03) to form an extension surface, and then designing the upper surface and the lower surface of the tenon based on the extension surface, and then reserving a machining allowance of 0.5-1.0 mm in the thickness direction of the upper surface and the lower surface of the tenon to obtain a tenon intermediate body; reserving a machining allowance of 5.0-10 mm on both sides of the tenon intermediate body to obtain a tenon preform (21); the tenon preform (21) and the blade body preform (23) constitute the blade preform (22); Step 2, manufacturing a shaping mold according to the blade preform (22); Step 3, determining the layer number of the blade body fiber cloth and the tenon fiber cloth according to the thickness of the blade body preform (23) and the tenon preform (21), respectively; determining the cutting size of the blade body fiber cloth and the tenon fiber cloth according to the size of the blade body preform (23) and the tenon preform (21), respectively, and cutting; Step 4, using the shaping mold and the blade body fiber cloth and the tenon fiber cloth cut in step 3 to shape the blade preform (22); Step 5, sewing and locking the edges of the shaped blade preform (22); Step 6, sequentially performing interface layer deposition and silicon carbide substrate layer deposition treatment on the blade preform (22) after locking the edges by using chemical vapor deposition method; Step 7, removing the shaping mold, and then performing mechanical processing and silicon carbide substrate deposition treatment on the blade preform (22) after deposition treatment to obtain a ceramic matrix composite blade.

2. The method according to claim 1, wherein in step 2, the shaping mold comprises an upper mold (3), a lower mold (4) and at least two fastening assemblies (8); the mounting surface of the upper mold (3) comprises a first arc convex surface and a second arc convex surface, the first arc convex surface is matched with the upper surface of the tenon preform (21), and the second arc convex surface is matched with the upper surface of the blade body preform (23); the mounting surface of the upper mold (3) is provided with a first sewing hole (9); two corner positions of the upper mold (3) are provided with first positioning holes (10); ​ The mounting surface of the lower mold (4) includes a first arc-shaped concave surface and a second arc-shaped concave surface, the first arc-shaped concave surface is matched with the lower surface of the tenon preform (21), and the second arc-shaped concave surface is matched with the lower surface of the blade preform (23); the mounting surface of the lower mold (4) is provided with a second sewing hole (11) corresponding to the first sewing hole (9); the lower mold (4) is provided with a second positioning hole (12) corresponding to the first positioning hole (10); The fastening assembly (8) is used to fasten the upper mold (3) and the lower mold (4) after the mold is closed; Step 4 specifically includes the following steps: Step 4.1, the cut blade fiber cloth in step 3 is stacked and laid on the second arc-shaped convex surface, then the cut tenon fiber cloth in step 3 is stacked and laid on the first arc-shaped convex surface until it is flush with the outermost blade fiber cloth, and finally the remaining tenon fiber cloth is stacked and laid on the first arc-shaped concave surface to obtain the stacked upper mold (3) and lower mold (4); Or, the cut blade fiber cloth in step 3 is stacked and laid on the second arc-shaped concave surface, then the cut tenon fiber cloth in step 3 is stacked and laid on the first arc-shaped concave surface until it is flush with the outermost blade fiber cloth, and finally the remaining tenon fiber cloth is stacked and laid on the first arc-shaped convex surface to obtain the stacked upper mold (3) and lower mold (4); Step 4.2, the stacked upper mold (3) and lower mold (4) are closed and fastened by the fastening assembly (8) to obtain the shaped blade preform (22); Step 4.3, the fit clearance of the shaped blade preform (22) and the upper mold (3) and the lower mold (4) is detected by using a 0.15mm caliper, if the fit clearance is ≥0.15mm, step 4.4 is executed, if the fit clearance is <0.15mm, step 5 is executed; Step 4.4, the fastening assembly (8) is disassembled, the newly cut blade fiber cloth and tenon fiber cloth are added on the outermost blade fiber cloth and tenon fiber cloth, and step 4.2 is returned.

3. The method for preparing the ceramic matrix composite blade according to claim 2, characterized in that: In step 2, the diameters of the first sewing hole (9) and the second sewing hole (11) are both 3-5mm, and the hole spacing of the adjacent first sewing hole (9) and the adjacent second sewing hole (11) is both 5-8mm; The mounting surface of the upper mold (3) and the mounting surface of the lower mold (4) are both equal wall thickness surfaces.

4. The method for preparing the ceramic matrix composite blade according to any one of claims 1-3, characterized in that: In step 3, the cut blade fiber cloth and tenon fiber cloth have a 6-10mm allowance for hemming.

5. The method of manufacturing a ceramic matrix composite blade according to claim 4, wherein, Step 5 is specifically: The shaped blade preform (22) is through-sewn, and then hemmed; the hemming needs to meet the following conditions: no needle drop, and needle spacing gap ≤3mm.

6. The method of manufacturing a ceramic matrix composite blade according to claim 5, wherein, Step 6 specifically includes the following steps: Step 6.1, the locked blade preform (22) is placed in a chemical vapor deposition furnace, then heated to 650-1000℃ under the condition of 50-1000Pa pressure in the furnace, and then argon, hydrogen, ammonia and boron trichloride are sequentially introduced for deposition until the blade preform (22) with a 150-750nm thick boron nitride interface layer is obtained, and then the temperature is kept for 1-3h, and then reduced to room temperature; Or, the locked blade preform (22) is placed in a chemical vapor deposition furnace, then heated to 500-1000℃ under the condition of 10-70Pa pressure in the furnace, and then argon and propylene are sequentially introduced for deposition until the blade preform (22) with a 100-350nm thick pyrolytic carbon interface layer is obtained, and then the temperature is kept for 1-3h, and then reduced to room temperature; Step 6.2: The blade preform (22) obtained in Step 6.1 is subjected to deposition under the conditions of a furnace internal pressure of 200-5000 Pa, temperature elevation to 900-1200 °C, and holding for 1-2 h, followed by introduction of a mixed gas of trichloromethylsilane, hydrogen, and argon at a flow ratio of 1-10:10-12:10-30, until a blade preform (23) having a density of 1.7-1.8 g / cm3 3 The blade preform (22) of the silicon carbide matrix layer having a density is held for 1-3 h, and then lowered to room temperature.

7. The method of manufacturing a ceramic matrix composite blade according to claim 6, wherein, Step 7 is specifically: After removing the upper mold (3) and the lower mold (4), the blade preform (22) obtained in step 6.2 is first mechanically processed, and then subjected to silicon carbide matrix deposition treatment according to the deposition method in step 6.2, until the density of the silicon carbide matrix layer is > 2.4 g / cm 3 , to obtain a ceramic matrix composite blade.

8. The method for preparing a ceramic matrix composite blade according to claim 2, characterized in that: In step 2, each of the fastening assemblies (8) comprises two pressing strips (6), two stud bolts (7) and four nuts (5); The two pressing strips (6) are respectively used for abutting against the opposite faces of the mounting surfaces of the upper mold (3) and the lower mold (4); The two stud bolts (7) are respectively used for penetrating through the two ends of the two pressing strips (6) and are fastened by the four nuts (5).

9. The method for preparing a ceramic matrix composite blade according to claim 8, characterized in that: The material of the shaping mold is a high-temperature-resistant material.

10. The method for preparing a ceramic matrix composite blade according to claim 9, characterized in that: The material of the shaping mold is a high-temperature-resistant material.

10. The method for preparing a ceramic matrix composite blade according to claim 9, characterized in that: The material of the shaping mold is a high-temperature-resistant material.

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