A ceramic matrix composite product labyrinth cavity member and flow directing deposition method

Abstract

The application discloses a ceramic matrix composite product labyrinth cavity component and a flow guide deposition method, which comprises a horizontal skeleton and a vertical skeleton constituting an internal frame, and process holes for CVI flow guide deposition are formed in the horizontal skeleton and the vertical skeleton; a plurality of hole groups for CVI flow guide deposition are formed on one side of the frame structure, the number of the plurality of hole groups is the same as the number of rows or columns of the internal frame, and the plurality of hole groups correspond to a plurality of frame rows or a plurality of frame columns of the frame structure one by one; the hole group comprises an air outlet hole and a flow guide hole; the flow guide hole is in sliding fit with a flow guide pipe used in CVI flow guide deposition; and a plugging structure is arranged at the air outlet hole and the flow guide hole. Through the labyrinth cavity structure, the determined skeleton part structure form, the assembly scheme and the interval distance between adjacent skeleton parts, the application has the advantages of simple assembly, only one CVI flow guide deposition process, shortened time cost, and facilitation of production promotion.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of flight protection products, in particular to a ceramic matrix composite product labyrinth cavity component and flow deposition method. BACKGROUND

[0002] Continuous fiber toughened silicon carbide ceramic matrix composite (CMC-SiC) as an internationally recognized new strategic and leading thermal structural material has a wide application prospect in the field of light-weight thermal protection products for aircraft. First, the skeleton parts are connected and assembled, and CVI deposition is performed, then the windward skin is connected and assembled with the skeleton assembly and CVI deposition is performed, finally the leeward skin is connected and assembled with the skeleton assembly and CVI flow deposition is performed. All assembly processes use C / SiC pins and C / SiC bolts with the same matrix for connection and assembly. The whole process needs to be operated multiple times for CVI flow deposition.

[0003] CVI flow deposition can achieve the effect of bolt loosening, and C / SiC pins achieve the effect of "metal riveting". C / SiC pin riveting is a connection method that combines bonding and fastening connection. First, the C / SiC rivet is assembled with the connected part using a tight fit method, and then SiC is deposited between the connected part and the rivet using chemical vapor infiltration, achieving a connection effect equivalent to "metal riveting". CVI welding method is an important connection method for the preparation of large and complex thin-walled CMC-SiC structural parts. Although C / SiC (SiC / SiC) pins using CVI riveting have the advantages of high connection strength and good reliability, when the deposition flow field of the riveting part is not smooth, single-sided deposition occurs, the welding between the pins and the pin holes is insufficient, the riveting strength is reduced, and finally the riveting part does not reach the designed bearing load, and the pins loosen and fall off prematurely.

[0004] In the prior art, CN105463410B "CVI densification method and gas pipeline structure for open container" discloses a substrate densification method for CVI densification of small opening complex containers, but it cannot solve the problem of connection reliability of C / SiC bolts and C / SiC pins in the assembly process of the product closed cavity; the invention can only solve the CVI densification deposition of the open container, and cannot solve the problem of CVI flow deposition in the closed cavity;

[0005] The prior art adopts an open CVI flow guide deposition method to prepare aircraft lightweight thermal protection products in order to uniformly deposit CVI flow guide deposition, but such a preparation process needs to be performed multiple times, the process is complex, and the assembly of screws or pins needs to be performed after each CVI flow guide deposition, which is likely to cause the CVI flow guide deposition layer to be scratched or cracked due to vibration, thereby reducing the overall protection life. SUMMARY

[0006] In view of the above problems of the prior art, the present application provides a ceramic matrix composite product labyrinth cavity component and a flow guide deposition method, which can perform CVI flow guide deposition on the inside and outside of the component after one-time assembly, and the deposition is uniform.

[0007] To achieve the above-mentioned purposes, the technical scheme adopted by the present application is as follows:

[0008] The present application provides a ceramic matrix composite product labyrinth cavity component, which comprises a plurality of horizontal skeletons and a plurality of longitudinal skeletons, the plurality of horizontal skeletons and the plurality of longitudinal skeletons are connected to form a frame structure, the frame structure is covered with a skeleton skin on the top and bottom, the skeleton skin isolates the internal frame of the frame structure from the outside, and the inner surface of the frame structure is covered with a CVI flow guide deposition layer;

[0009] The horizontal skeletons and the longitudinal skeletons constituting the internal frame are each provided with a process hole for CVI flow guide deposition;

[0010] One side of the frame structure is provided with a plurality of hole groups for CVI flow guide deposition, the number of the plurality of hole groups is the same as the number of rows or columns of the internal frame, and the plurality of hole groups correspond one-to-one to a plurality of frame rows or a plurality of frame columns of the frame structure; each hole group comprises an air outlet hole and a flow guide hole;

[0011] The flow guide hole is in sliding fit with a flow guide pipe used in CVI flow guide deposition; and a plugging structure is arranged at the air outlet hole and the flow guide hole.

[0012] By arranging the process holes on the skeletons, on the one hand, a deposition channel is formed in the internal frame structure, thereby solving the problem that the internal cavity of the closed cavity cannot be subjected to CVI flow guide deposition or the problem of low deposition efficiency; on the other hand, the arrangement of the process holes reduces the overall weight of the component, thereby enabling the component to be better applied to flight protection products. The internal frame structure is formed into a labyrinth cavity through the process holes, and the air outlet hole and the flow guide hole are used to effectively prevent single-sided deposition in the internal frame structure.

[0013] Further, the distance p between the process hole and the edge of the horizontal skeleton or the longitudinal skeleton is greater than or equal to 5 mm.

[0014] Further, the diameter of the air outlet hole, the diameter of the flow guide hole and the outer diameter of the flow guide pipe are the same, all being Φ1, and a plurality of radial air outlet holes (11) are arranged on the flow guide pipe, the radial air outlet holes have a diameter wherein, Φ2 is the inner diameter of the flow guide pipe.

[0015] Further, the flow guide pipe is a hollow circular pipe, and a plurality of radial gas outlet holes are formed on the flow guide pipe; the inner diameter of the flow guide pipe is Φ2≥8mm; the diameter of the plurality of radial gas outlet holes is Φ3∈[20Φ2, 60Φ2]; during CVI flow deposition, one end of the flow guide pipe is located inside the frame structure, and the other end of the flow guide pipe is connected with the deposition furnace.

[0016] Further, a flow splitting device is arranged between the flow guide pipe and the deposition furnace, the flow splitting device comprises a square flow splitting box, one end of the flow splitting box is provided with a gas inlet hole connected with the deposition furnace, and the other end of the flow splitting box is provided with one or more flow splitting holes, the diameter of the flow splitting hole is Φ4≥12mm; the length of the flow splitting box is L∈[2Φ4, 15Φ4].

[0017] The arrangement of the flow splitting device enables one deposition furnace to simultaneously introduce reaction gas into the inside of the frame structure for CVI flow deposition, which can effectively speed up the deposition efficiency.

[0018] Further, the plugging structure comprises one or a combination of a plugging screw and a plugging plate;

[0019] The head diameter of the plugging screw is greater than the diameter of the gas outlet hole or the flow guide hole by 4-10mm;

[0020] The plugging plate is made of silicon carbide, and the thickness h of the plugging plate is ≤5mm; the length l of the plugging plate is ∈[2Φ1, 15Φ1], wherein Φ1 is the diameter of the gas outlet hole, the diameter of the flow guide hole and the outer diameter of the flow guide pipe; the width d of the plugging plate is l, and when the width of the plugging plate is greater than the frame height where the hole group is located, the width d of the plugging plate is equal to the frame height where the hole group is located.

[0021] Further, the plugging plate is made by bonding several layers of silicon carbide cloth. The bonding of several layers of silicon carbide cloth enables the plugging plate to fit the outer surface of the frame structure, thereby making the plugging effect of the plugging plate better.

[0022] Further, the inner wall of the frame structure where the hole group is located is provided with a threaded hole reinforcing plate, and the thickness h' of the threaded hole reinforcing plate is ∈[5mm, 10mm].

[0023] The arrangement of the threaded hole reinforcing plate enables the gas outlet hole or the flow guide hole to have sufficient thickness to form threads, and the number of turns of the threads is increased, thereby making the cooperation between the plugging screw and the frame structure stable and having good airtightness.

[0024] A flow deposition method for a ceramic matrix composite product labyrinth cavity member, comprising the following specific steps:

[0025] S1: the labyrinth cavity component is assembled by connecting a plurality of transverse frameworks, a plurality of longitudinal frameworks and a framework skin using screws and pins;

[0026] S2: one end of the flow guide pipe is inserted into the lattice structure from the flow guide hole, the other end of the flow guide pipe is connected with the deposition furnace, and the inside of the lattice structure is subjected to CVI flow guide deposition by using the deposition furnace;

[0027] S3: after the CVI flow guide deposition is completed, high-temperature ceramic glue is configured, and the air outlet hole and the flow guide hole are plugged by using the high-temperature ceramic glue and the plugging structure;

[0028] when the plugging structure is a plugging screw, the high-temperature ceramic glue is applied to the plugging screw, the air outlet hole, the flow guide hole and the periphery of the holes to be plugged, and the air outlet hole and the flow guide hole are plugged by using the plugging screw;

[0029] when the plugging structure is a plugging plate, a plurality of layers of silicon carbide cloth are used to cover the air outlet hole, the flow guide hole and the periphery thereof by using the high-temperature ceramic glue, and each layer of the silicon carbide cloth is bonded by using the high-temperature ceramic glue;

[0030] when the plugging structure is a plugging screw and a plugging plate, the high-temperature ceramic glue is applied to the plugging screw, the air outlet hole, the flow guide hole and the periphery of the holes to be plugged, the air outlet hole and the flow guide hole are plugged by using the plugging screw, the head of the plugging screw is cut off, and then a plurality of layers of silicon carbide cloth are used to cover the periphery of the plugging screw, the air outlet hole and the flow guide hole by using the high-temperature ceramic glue, and each layer of the silicon carbide cloth is bonded by using the high-temperature ceramic glue;

[0031] S4: the device is subjected to high-temperature ceramic glue curing treatment, after the curing treatment, the plugging structure seals the air outlet hole and the flow guide hole, when the plugging plate is used as the plugging structure, the plurality of layers of silicon carbide cloth form the plugging plate, and finally the labyrinth cavity component capable of being applied to the light-weight thermal protection of an aircraft is obtained.

[0032] Further, the high-temperature ceramic glue comprises: polyborosilazane PBSZ and titanium powder mixed at a weight ratio of 1:1 to 4:1.

[0033] The high-temperature ceramic glue is cured by using a first curing method or a second curing method; the first curing method comprises: placing the structure as a whole in an environment at 26-40 DEG C, and naturally drying for 7 days;

[0034] the second curing method comprises: placing the structure as a whole into an oven, heating to 100 DEG C by using the oven and keeping the temperature for 24-48 hours.

[0035] The beneficial effects of the present application are:

[0036] 1. The labyrinth cavity structure, the determined framework part structure form, the assembly scheme and the adjacent framework part spacing distance are set, the deposition efficiency of the closed cavity is solved for subsequent flow deposition, and the implementation scheme is proposed from the product structure principle;

[0037] 2. The CVI flow deposition method inside the closed cavity solves the single-sided deposition of the riveting pin of the leeward skin of the closed cavity, the poor deposition quality, the falling problem caused by the unreliable connection quality of the pin and bolt, achieves the functions of pin metal riveting and bolt anti-loosening, and improves the overall assembly quality of the product;

[0038] 3. A preparation method of high-temperature ceramic glue is provided, the high-temperature ceramic glue solves the anti-loosening of the threaded connection pair of ceramic matrix composite (C / SiC and SiC / SiC) and the bonding of the ceramic matrix composite sheet and the ceramic matrix composite member. The temperature range is-120-1000 DEG C, and the short-time can reach 1650 DEG C.

[0039] 4. The labyrinth cavity component of the present application is simple to assemble, the deposition furnace body gas path part is deposited inside the product through the flow channel, the remaining part of the deposition furnace body gas path is deposited outside the open area of the product, only one CVI flow deposition process is needed, the inside and outside of the product can be effectively deposited, the whole process is simple, the time cost is shortened, and it is beneficial to production promotion. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 It is an internal structure schematic diagram when the labyrinth cavity component is subjected to CVI flow deposition;

[0041] Figure 2 It is a three-dimensional structure schematic diagram of the flow guide pipe;

[0042] Figure 3 It is a three-dimensional structure schematic diagram after the plugging screw plugging hole group;

[0043] Figure 4 It is a three-dimensional structure schematic diagram after the plugging plate plugging the plugging screw;

[0044] 1, horizontal skeleton; 2, longitudinal skeleton; 3, frame structure; 4, skeleton skin; 5, process hole; 6, hole group; 7, gas outlet hole; 8, flow guide hole; 9, flow guide pipe; 10, plugging screw; 11, radial gas outlet hole; 12, shunt box; 13, plugging plate. DETAILED DESCRIPTION

[0045] The specific embodiments of the present application are described below to facilitate the understanding of the present application for those skilled in the art, but it should be clear that the present application is not limited to the scope of the specific embodiments, and for those skilled in the art, it is obvious that various changes are within the spirit and scope of the present application defined and determined by the appended claims, and all the inventions utilizing the concept of the present application are within the scope of protection.

[0046] Embodiment 1

[0047] As Figures 1-2 shown, a ceramic matrix composite product labyrinth cavity member includes a plurality of transverse skeletons 1 and a plurality of longitudinal skeletons 2, the plurality of transverse skeletons 1 and the plurality of longitudinal skeletons 2 are connected to form a frame structure 3, the frame structure 3 is covered with a skeleton skin 4 on the top and bottom, the skeleton skin 4 isolates the internal frame of the frame structure 3 from the outside, and the inner surface of the frame structure 3 is covered with a CVI flow guide deposition layer; in specific implementation, the gap D between adjacent two transverse skeletons 1 or adjacent two longitudinal skeletons 2 is ≤250mm; the skeleton skin 4 and the frame structure 3 are riveted by a pin.

[0048] The transverse skeletons 1 and the longitudinal skeletons 2 constituting the internal frame are both provided with process holes 5 for CVI flow guide deposition;

[0049] A plurality of hole groups 6 for CVI flow guide deposition are provided on one side of the frame structure 3, the number of the plurality of hole groups 6 is the same as the number of rows or columns of the internal frame, and the plurality of hole groups 6 correspond to the plurality of frame rows or the plurality of frame columns of the frame structure 3 one by one; the hole group 6 includes an air outlet hole 7 and a flow guide hole 8; in specific implementation, the air outlet hole 7 and the flow guide hole 8 are only the names of the holes, not fixed hole positions, and the air outlet hole 7 can also be the flow guide hole 8; when CVI flow guide deposition is performed, at least one flow guide hole 8 and at least one air outlet hole 7 are ensured in one hole group 6, and the number of the flow guide holes 8 is 1-2 times the number of the air outlet holes 7.

[0050] The air outlet hole 7 and the flow guide hole 8 can be directly drilled when the frame structure 3 is prepared, or the frame structure 3 can be assembled and then positioned using a drilling template and drilled using a diamond-coated cutter.

[0051] Whether the hole group 6 is located on the row side or the column side of the frame structure 3 is selected according to the actual situation, and the number of rows and columns is compared, and the larger value is preferred, that is, when the number of rows is greater than the number of columns, the hole group 6 is located on the row side of the frame structure 3, which can shorten the length of the flow guide pipe 9 and shorten the moving distance of the inlet gas and the outlet gas of the CVI flow guide deposition, which is beneficial to the uniform deposition of CVI in the frame structure 3; the selected position of the hole group 6 does not affect the appearance of the finished product.

[0052] The flow guide hole 8 is in sliding fit with the flow guide pipe 9 used in CVI flow guide deposition; the outlet hole 7 and the flow guide hole 8 are provided with a plugging structure.

[0053] The distance p of the process hole 5 from the edge of the transverse framework 1 or the longitudinal framework 2 is greater than or equal to 5 mm, so that the arrangement of the process hole 5 does not affect the overall structural strength of the product.

[0054] The diameter of the outlet hole 7, the diameter of the flow guide hole 8 and the outer diameter of the flow guide pipe 9 are the same, all being Φ1, and a plurality of radial outlet holes 11 are formed on the flow guide pipe 9, the diameter of the radial outlet hole being Φ3∈[20Φ2, 60Φ2]. Wherein, Φ2 is the inner diameter of the flow guide pipe 9.

[0055] The flow guide pipe 9 is a hollow circular pipe, and a plurality of radial outlet holes 11 are formed on the flow guide pipe 9; the inner diameter Φ2 of the flow guide pipe 9 is greater than or equal to 8 mm; the diameter of the plurality of radial outlet holes 11 is Φ3∈[20Φ2, 60Φ2]; during CVI flow guide deposition, one end of the flow guide pipe 9 is located inside the frame structure 3, and the other end of the flow guide pipe 9 is connected with the deposition furnace. In specific implementation, the radial outlet holes 11 on the flow guide pipe 9 are unevenly distributed, the openings of the radial outlet holes 11 should be as close to the deposition surface as possible, and the number is in direct proportion to the deposition surface area of the closed cavity and in direct proportion to the distance between the closed cavity and the flow guide hole 8. In specific implementation, the flow guide pipe 9 is made of C / SiC composite pipe, and can also be processed into a pipe shape by high-temperature graphite;

[0056] In specific implementation, the length of the flow guide pipe 9 is determined according to the depth of the internal frame, and the length of the flow guide pipe 9 is preferably 1 / 3 of the depth of the internal frame.

[0057] A flow splitting device is arranged between the flow guide pipe 9 and the deposition furnace, and the flow splitting device comprises a flow splitting box 12, one end of the flow splitting box 12 is provided with a gas inlet hole connected with the deposition furnace, and the other end of the flow splitting box 12 is provided with one or more flow splitting holes, the diameter Φ4 of the flow splitting hole is greater than or equal to 12 mm; the length L of the square flow splitting box 12 is ∈[2Φ4, 15Φ4]. In specific implementation, the flow splitting box 12 can also be square, cylindrical or conical.

[0058] The arrangement of the flow splitting device enables one deposition furnace to simultaneously introduce reaction gas into the internal frame structure 3 for CVI flow guide deposition, which can effectively speed up the deposition efficiency.

[0059] The plugging structure comprises one or a combination of a plugging screw 10 and a plugging plate 13;

[0060] The head diameter of the plugging screw 10 is greater than the diameter of the outlet hole 7 or the flow guide hole 8 by 4-10 mm;

[0061] The plugging plate 13 is made of silicon carbide, and the thickness h of the plugging plate 13 is less than or equal to 5 mm; the length l of the plugging plate 13 is in the range of [2Φ1, 15Φ1], where Φ1 is the diameter of the gas outlet hole 7, the diameter of the flow guide hole 8, and the outer diameter of the flow guide pipe 9; the width d of the plugging plate 13 is equal to the length l, and when the width of the plugging plate 13 is greater than the frame height where the hole group 6 is located, the width d of the plugging plate 13 is equal to the frame height where the hole group 6 is located. In specific implementation, carbon cloth can be used instead of silicon carbide cloth. Or, a 2D C / SiC flat plate of the same size specification is used instead of the silicon carbide cloth. After the 2D C / SiC flat plate is riveted to the product through the same base dowel, CVD chemical vapor deposition is performed on the product, which can also achieve the plugging of the flow guide hole 8.

[0062] When plugging the plugging screw 10, the silicon carbide cloth can be cut into a shape suitable for the shape of the product, which is beneficial to improve the bonding area and improve the bonding strength.

[0063] The plugging plate 13 is made by bonding several layers of silicon carbide cloth. The bonding of several layers of silicon carbide cloth allows the plugging plate 13 to fit the outer surface of the frame structure 3, thereby improving the plugging effect of the plugging plate 13. In specific implementation, the silicon carbide cloth is 2 layers or 3 layers. In other embodiments, it can also be 4 layers or 5 layers; as long as the thickness of the plugging plate 13 obtained by bonding the silicon carbide cloth after curing is less than or equal to 5 mm.

[0064] The inner wall of the frame structure 3 where the hole group 6 is located is provided with a threaded hole reinforcing plate, and the thickness h' of the threaded hole reinforcing plate is in the range of [5 mm, 10 mm].

[0065] Embodiment 2

[0066] As shown in Figure 3 A flow guide deposition method for a ceramic matrix composite product labyrinth cavity component, comprising the following specific steps:

[0067] S1: connecting and assembling the labyrinth cavity component by using screws and dowels to connect a plurality of horizontal skeletons 1, a plurality of longitudinal skeletons 2, and a skeleton skin 4;

[0068] S2: one end of the flow guide pipe 9 extends into the frame structure 3 from the flow guide hole 8, the other end of the flow guide pipe 9 is connected with the deposition furnace, and the frame structure 3 inside is subjected to CVI flow guide deposition using the deposition furnace; the reaction gas is introduced into the frame structure 3 through the flow guide pipe 9 via a flow dividing device, the flow guide pipe 9 is not inserted into the gas outlet hole 7, and the reaction tail gas is discharged from the frame structure 3 through the gas outlet hole 7 by the pressure difference between the inside and outside of the frame structure 3, enters the inside of the deposition furnace body, and is discharged through the gas path of the furnace body itself. The setting of the process hole 5 causes the reaction gas to have multiple flow directions inside the labyrinth cavity, thereby avoiding the occurrence of single-sided deposition.

[0069] S3: After the CVI flow deposition is completed, high-temperature ceramic glue is configured, and the air outlet hole 7 and the flow guide hole 8 are plugged by using the high-temperature ceramic glue in cooperation with the plugging screw 10; in specific implementation, after the high-temperature ceramic glue is applied to the screw rod of the plugging screw 10 and the periphery of the air outlet hole 7 and the flow guide hole 8, the plugging screw 10 is screwed to plug the air outlet hole 7 and the flow guide hole 8; when the periphery of the air outlet hole 7 and the flow guide hole 8 is applied with the high-temperature ceramic glue, the diameter range of the high-temperature ceramic glue is 1-2 mm larger than the diameter of the head of the plugging screw 10; in specific implementation, before the air outlet hole 7 and the flow guide hole 8 are plugged, the residual excess inside the frame is cleaned, and the residual excess is sucked and cleaned from the air outlet hole 7 or the flow guide hole 8 by using a dust collector;

[0070] S4: The device is subjected to high-temperature ceramic glue curing treatment, and finally a labyrinth cavity component capable of being applied to aircraft lightweight thermal protection is obtained; in specific implementation, after the high-temperature ceramic glue is cured, the surface is polished.

[0071] The high-temperature ceramic glue comprises: polyborosilazane PBSZ and titanium powder mixed and prepared at a weight ratio of 1:1-4:1;

[0072] The high-temperature ceramic glue curing adopts a first curing method or a second curing method; the first curing method comprises: the whole structure is placed in an environment at 26-40℃, and naturally dried for 7 days;

[0073] The second curing method comprises: the whole structure is placed in an oven, and heated to 100℃ by using the oven and kept for curing for 24-48 hours.

[0074] Embodiment 3

[0075] The difference between this embodiment and embodiment 2 is that step S3 is: after the CVI flow deposition is completed, high-temperature ceramic glue is configured, and the air outlet hole 7 and the flow guide hole 8 are plugged by using the high-temperature ceramic glue in cooperation with the plugging screw 10; in specific implementation, after the high-temperature ceramic glue is applied to the screw rod of the plugging screw 10 and the periphery of the air outlet hole 7 and the flow guide hole 8, the plugging screw 10 is screwed to plug the air outlet hole 7 and the flow guide hole 8; when the periphery of the air outlet hole 7 and the flow guide hole 8 is applied with the high-temperature ceramic glue, the diameter range of the high-temperature ceramic glue is 1-2 mm larger than the diameter of the head of the plugging screw 10; in specific implementation, before the air outlet hole 7 and the flow guide hole 8 are plugged, the residual excess inside the frame is cleaned, and the residual excess is sucked and cleaned from the air outlet hole 7 or the flow guide hole 8 by using a dust collector; Figure 4

[0076] Embodiment 4

[0077] The difference between this embodiment and embodiment 2 is that step S3 is: the plugging screw 10, the air outlet hole 7, the flow guide hole 8 and the periphery to be plugged are coated with high-temperature ceramic glue, the air outlet hole 7 and the flow guide hole 8 are plugged by using the plugging screw 10, the head of the plugging screw 10 is cut off, and then a plurality of layers of silicon carbide cloth are adhered to the periphery of the plugging screw 10, the air outlet hole 7 and the flow guide hole 8 by using high-temperature ceramic glue, and each layer of silicon carbide cloth is adhered by using high-temperature ceramic glue; after curing treatment, the plurality of layers of silicon carbide cloth form a plugging plate 13.​

Claims

1. A labyrinth cavity component for a ceramic matrix composite product, comprising a plurality of transverse skeletons (1) and a plurality of longitudinal skeletons (2), wherein the plurality of transverse skeletons (1) and the plurality of longitudinal skeletons (2) are connected to form a frame structure (3), the frame structure (3) is covered with skeleton skins (4) on the top and bottom, the skeleton skins (4) isolate the internal frames of the frame structure (3) from the outside, and the inner surface of the frame structure (3) is covered with a CVI flow-guiding deposition layer; characterized in that, Both the transverse skeleton (1) and the longitudinal skeleton (2) that form the internal frame are provided with process holes (5) for CVI flow deposition. The frame structure (3) has a plurality of hole groups (6) for CVI flow deposition on one side. The number of the plurality of hole groups (6) is the same as the number of rows or columns of the internal frame, and the plurality of hole groups (6) corresponds one-to-one with the plurality of frame rows or columns of the frame structure (3). The hole group (6) includes an air outlet (7) and a flow guide (8). The guide hole (8) is slidably fitted with the guide tube (9) used in CVI guide deposition; a sealing structure is provided at the air outlet (7) and the guide hole (8); The distance between the process hole (5) and the edge of the transverse skeleton (1) or the longitudinal skeleton (2) p ≥5mm; The diameters of the air outlet (7), the guide hole (8), and the outer diameter of the guide pipe (9) are all the same. Furthermore, the guide pipe (9) is provided with several radial air outlet holes (11), the diameter of which is... ;in, The inner diameter of the guide tube (9); The flow-guiding deposition method used in the labyrinth cavity component of the ceramic matrix composite product includes the following specific steps: S1: Several transverse skeletons, several longitudinal skeletons, and skeleton skin will be connected and assembled using screws and pins to obtain the labyrinth cavity component; S2: Insert one end of the guide tube into the frame structure through the guide hole, and connect the other end of the guide tube to the deposition furnace. Use the deposition furnace to perform CVI guided deposition inside the frame structure. S3: After the CVI flow-guiding deposition is completed, high-temperature ceramic adhesive is prepared and used in conjunction with the sealing structure to seal the vent and flow-guiding holes; When the sealing structure is a sealing screw, apply high-temperature ceramic adhesive to the sealing screw, vent hole, guide hole and the area around the hole to be sealed, and use the sealing screw to tighten and plug the vent hole and guide hole; When the sealing structure is a sealing plate, several layers of silicon carbide cloth are bonded to the vent holes, flow holes and their surroundings with high-temperature ceramic adhesive. Each layer of silicon carbide cloth is bonded with high-temperature ceramic adhesive. When the sealing structure consists of sealing screws and sealing plates, apply high-temperature ceramic adhesive to the sealing screws, vent holes, guide holes, and the area around the holes to be sealed. Tighten the sealing screws to plug the vent holes and guide holes. Cut off the screw heads. Then, apply several layers of silicon carbide cloth with high-temperature ceramic adhesive to the sealing screws and the area around the vent holes and guide holes. Each layer of silicon carbide cloth is bonded with high-temperature ceramic adhesive. S4: The device is cured with high-temperature ceramic adhesive. After curing, the sealing structure seals the vent and guide hole. When the sealing plate is used as the sealing structure, several layers of silicon carbide cloth form the sealing plate. Finally, a labyrinth cavity component that can be used for lightweight thermal protection of aircraft is obtained.

2. The labyrinth cavity component of the ceramic matrix composite product according to claim 1, characterized in that, The guide tube (9) is a hollow circular tube, and several radial air outlet holes (11) are opened on the guide tube (9); the inner diameter of the guide tube (9) is... The diameter of the plurality of radial vent holes (11) and During CVI flow deposition, one end of the flow pipe (9) is located inside the frame structure (3), and the other end of the flow pipe (9) is connected to the deposition furnace.

3. The labyrinth cavity component of the ceramic matrix composite product according to claim 1, characterized in that, A flow divider is provided between the guide pipe (9) and the deposition furnace. The flow divider includes a square flow divider box (12). One end of the flow divider box (12) is provided with a gas supply port connected to the deposition furnace, and the other end of the flow divider box (12) is provided with one or more flow divider holes. The diameter of the flow divider holes is... The length of the shunt box (12) .

4. The labyrinth cavity component of the ceramic matrix composite product according to claim 1, characterized in that, The sealing structure includes one or a combination of sealing screws (10) and sealing plates (13); The diameter of the head of the sealing screw (10) is 4~10mm larger than the diameter of the vent hole (7) or the guide hole (8); The sealing plate (13) is made of silicon carbide, and the thickness of the sealing plate (13) is... h ≤5mm; the length of the sealing plate (13) ,in, The diameter of the air outlet (7), the diameter of the guide hole (8), and the outer diameter of the guide tube (9); the width of the sealing plate (13). d=l And when the width of the sealing plate (13) is greater than the height of the frame where the hole group (6) is located, the width of the sealing plate (13) is... d It is equal to the height of the frame where the hole group (6) is located.

5. The labyrinth cavity component of the ceramic matrix composite product according to claim 4, characterized in that, The sealing plate (13) is made by bonding several layers of silicon carbide cloth.

6. The labyrinth cavity component of the ceramic matrix composite product according to claim 1, characterized in that, The inner wall of the frame structure (3) where the hole group (6) is located is provided with a screw hole reinforcing plate, and the thickness of the screw hole reinforcing plate is... .

7. The labyrinth cavity component of the ceramic matrix composite product according to claim 1, characterized in that, The high-temperature ceramic adhesive comprises: polyborosilazane PBSZ and titanium powder mixed in a weight ratio of 1:1 to 4:1; The high-temperature ceramic adhesive is cured using either the first curing method or the second curing method; the first curing method includes placing the entire structure in an environment of 26–40°C and allowing it to air dry for 7 days. The second curing method includes: placing the entire structure into an oven, heating it to 100°C and maintaining the temperature for 24-48 hours.

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