A thin-walled ceramic matrix composite material with heat dissipation function and a preparation method thereof

Abstract

The present application relates to a kind of thin-walled ceramic matrix composite with heat dissipation function and its preparation method.The thin-walled ceramic matrix composite uses PAN-based fiber spread band and mesophase pitch-based fiber spread band mixed thin-walled preform, and is prepared by combining CVI and PIP matrix densification process.The method first uses 2.5D weaving technology to prepare PAN-based fiber spread band and mesophase pitch-based fiber spread band mixed thin-walled preform, then uses CVI process to deposit pyrolytic carbon interface layer on the surface of carbon fiber, and then uses CVI and PIP process to densify SiC ceramic matrix respectively.The thin-walled ceramic matrix composite with heat dissipation function prepared by the present application has very thin thickness (≤1mm), which can meet the development requirements of aircraft lightweight sandwich structure panel.

Description

TECHNICAL FIELD

[0001] The present application relates to a carbon fiber reinforced ceramic matrix composite material, in particular to a thin-walled ceramic matrix composite material with heat dissipation function and a preparation method thereof. BACKGROUND

[0002] The structure of aircraft aileron and the like requires higher and higher light weight, in order to prepare a light weight sandwich structure, the requirement for the thickness of the sandwich panel is also thinner and thinner, and good strength and modulus are required; in addition, during high-speed flight of the aircraft, the structure of aileron and the like will bear a large thermal stress, in order to reduce the thermal stress, higher requirements for the heat dissipation capacity are put forward.

[0003] 2.5D structure refers to a whole structure formed by introducing weft fibers when the adjacent two layers of warp fibers exchange positions. The 2.5D woven fiber reinforced composite material not only maintains the advantages of the laminated structure of the composite material, but also better eliminates the low interlayer strength and poor damage resistance caused by the interlayer weakness of the laminated composite material, greatly improves the performance of the composite material, and makes it have better designability.

[0004] The fiber spreading can extend a single fiber to a very thin one, and the 2.5D structure thin-walled preform obtained by weaving the spread fiber tape has more layers per unit thickness, and therefore has more stable and uniform mechanical properties; and at the same time having the advantages of 2.5D structure, compared with the needled structure carbon fiber preform and the stitched structure carbon fiber preform, its surface is smoother, and is particularly suitable for the preparation of thin-walled ceramic matrix composite material. SUMMARY

[0005] In order to solve the problems in the prior art, the present application provides a thin-walled ceramic matrix composite material with heat dissipation function and a preparation method thereof.

[0006] In order to achieve the above purpose, the present application provides the following technical scheme:

[0007] In a first aspect, the present application provides a preparation method of a thin-walled ceramic matrix composite material with heat dissipation function, comprising the following steps:

[0008] (1) preparing a PAN (polyacrylonitrile) based fiber spread tape and an intermediate phase pitch based fiber spread tape mixed thin-walled preform, and performing high temperature preheating treatment thereon;

[0009] (2) depositing a pyrolytic carbon interface layer on the fiber surface of the thin-walled preform by chemical vapor deposition (CVI method), and performing high temperature graphitization treatment thereon;

[0010] (3) The CVI method and the precursor impregnation and cracking method (PIP method) were used to densify the SiC ceramic matrix of the carbon-deposited thin-walled preform after high-temperature graphitization treatment to obtain a thin-walled ceramic-based composite material with heat conduction function.

[0011] Preferably, the thin-walled preform is prepared by using a wide band of PAN-based fibers and a wide band of mesophase pitch-based fibers in combination with 2.5D weaving technology.

[0012] Preferably, the expanded width of the mesophase pitch-based fiber is 10 to 20 mm.

[0013] Preferably, the PAN-based fibers are T-series fibers with an expanded width of 10 to 30 mm.

[0014] Preferably, the thin-walled preform adopts a 2.5D woven structure.

[0015] Preferably, the temperature of the high-temperature preheating treatment of the thin-walled preform is 1800-2000° C., and the holding time is 2-3 hours; the purpose of the high-temperature preheating treatment is to remove organic matter inside the preform.

[0016] Preferably, a pyrolytic carbon interface layer is deposited on the fiber surface of the thin-walled preform using the CVI method, the carbon source used is propylene, the carrier gas is nitrogen, the deposition temperature is 800-1100°C, and the deposition time depends on the density of the thin-walled preform after the pyrolytic carbon is deposited.

[0017] Preferably, the density of the thin-walled preform after the deposition of pyrolytic carbon is 0.9 to 1.1 g / cm 3 .

[0018] Preferably, the temperature of the high-temperature graphitization treatment is 2400-3200°C.

[0019] Preferably, in step (3), the CVI process is used to densify the SiC ceramic matrix of the carbon-deposited thin-walled preform after high-temperature graphitization treatment, which is referred to as the CVI-SiC process. The CVI-SiC process deposition uses trichloromethylsilane MTS (CH3SiCl3) as the reaction gas, H2 gas as the carrier gas, Ar gas as the dilution gas, the deposition temperature is 1000-1100°C, the reaction gas flow rate is 50-100g / min, and the H2 flow rate is 0.15-0.25m 3 / h, Ar gas flow rate is 0.2~0.4m 3 / h.

[0020] Preferably, the deposition time of the CVI-SiC process is 80 to 100 hours.

[0021] Preferably, in step (3), the PIP process is used to further densify the SiC ceramic matrix, referred to as the PIP-SiC process. The PIP process includes impregnation, curing and high-temperature cracking. The PIP-SiC process uses liquid polycarbosilane as a ceramic precursor. The impregnation temperature is 10-100°C, the impregnation pressure is 0.5-2MPa, and the impregnation time is 0.5-2h; the curing temperature is 100-350°C, the curing pressure is 0.5-2MPa, and the curing time is 0.5-2h; the high-temperature cracking temperature is 900-1200°C, and the cracking time is 2-4h. The number of PIP cycles depends on the density of the thin-walled ceramic matrix composite material with heat conduction function.

[0022] Preferably, the density of the thin-walled ceramic matrix composite material with heat conduction function is 1.9-2.0 g / cm 3 .

[0023] In a second aspect, the present invention provides a thin-walled ceramic-based composite material with heat conduction function prepared by the above method.

[0024] Compared with the prior art, the present invention has at least the following beneficial effects:

[0025] The thin-walled ceramic-based composite material with heat-conducting function prepared by the present invention is not only thin in thickness (≤1mm), but also has good strength and modulus, and also has good heat-conducting ability, which can significantly reduce the thermal stress of the aircraft during high-speed flight. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] The present invention provides a thin-walled ceramic-based composite material with a heat-conducting function and a preparation method thereof, wherein the preparation method comprises the following steps:

[0028] (1) preparing a thin-wall preform of a mixed PAN (polyacrylonitrile)-based fiber wide band and a mesophase pitch-based fiber wide band, and performing a high-temperature preheating treatment on the preform;

[0029] (2) using chemical vapor deposition (CVI) to deposit a pyrolytic carbon interface layer on the fiber surface of the thin-walled preform and subjecting it to high-temperature graphitization treatment;

[0030] (3) The CVI method and the precursor impregnation and cracking method (PIP method) were used to densify the SiC ceramic matrix of the carbon-deposited thin-walled preform after high-temperature graphitization treatment to obtain a thin-walled ceramic-based composite material with heat conduction function.

[0031] The present invention first widens PAN-based fibers and mesophase asphalt-based fibers to prepare wide fiber bands, and then adopts 2.5D weaving technology to weave a thin-walled preform. Fiber widening can extend a single fiber to a very thin layer. The 2.5D structural thin-walled preform obtained by weaving the widened fiber band has more layers per unit thickness, and therefore has more stable and uniform mechanical properties. The 2.5D structural thin-walled preform obtained by weaving the widened fibers has a smoother surface than the needle-punched carbon fiber preform and the stitched carbon fiber preform, while having its structural advantages, and is particularly suitable for the preparation of thin-walled ceramic-based composite materials.

[0032] According to some preferred embodiments, the mesophase pitch-based fibers have an expanded width of 10 to 20 mm; the PAN-based fibers are T-series fibers with an expanded width of 10 to 30 mm; and the thin-walled preforms have a 2.5D woven structure.

[0033] Preferably, the preform is preheated at a temperature of 1800-2000° C. and held at this temperature for 2-3 hours.

[0034] According to some preferred embodiments, a pyrolytic carbon interface layer is deposited on the fiber surface of the thin-walled preform by the CVI method, the carbon source used is propylene, the carrier gas is nitrogen, the deposition temperature is 800-1100°C, and the deposition density is 0.9-1.1 g / cm 3 .

[0035] Preferably, the high-temperature graphitization temperature is 2400-3200°C.

[0036] According to some preferred embodiments, the CVI-SiC process deposition uses trichloromethylsilane MTS (CH3SiCl3) as the reaction gas, H2 gas as the carrier gas, Ar gas as the dilution gas, the deposition temperature is 1000-1100 ° C, the reaction gas flow rate is 50-100 g / min, the H2 flow rate is 0.15-0.25 m 3 / h, Ar gas flow rate is 0.2~0.4m 3 / h, deposition time 80-100h; the PIP-SiC process uses liquid polycarbosilane as a ceramic precursor, the impregnation temperature is 10-100°C, the impregnation pressure is 0.5-2MPa, and the impregnation time is 0.5-2h; the curing temperature is 100-350°C, the curing pressure is 0.5-2MPa, and the curing time is 0.5-2h; the high-temperature pyrolysis temperature is 900-1200°C, and the pyrolysis time is 2-4h. The densified density of the thin-walled ceramic-based composite material with heat conduction function is 1.9-2.0g / cm 3 .

[0037] In order to more clearly illustrate the technical solutions and advantages of the present invention, the present invention is further described below with reference to embodiments.

[0038] Example 1

[0039] A thin-walled ceramic-based composite material with heat conduction function and a preparation method thereof, wherein the specific steps are as follows:

[0040] (1) Shaanxi Tiance TC-22B 1K mesophase asphalt-based carbon fiber and PAN-based T300 3K fiber were used to prepare a thin-walled preform with heat conduction function. First, Shaanxi Tiance TC-22B 1K mesophase asphalt-based carbon fiber was widened to 10 mm, and PAN-based T300 3K fiber was widened to 15 mm. Then, a thin-walled preform was prepared using 2.5D weaving technology.

[0041] (2) The thin-walled preform was subjected to a high-temperature preheating treatment at 1800°C for 2 hours, and then a pyrolytic carbon interface layer was deposited on the surface of the preform fiber using the CVI method. The carbon source used was propylene, the carrier gas was nitrogen, and the deposition temperature was preferably 900°C. The density of the preform after pyrolytic carbon deposition was 1.05 g / cm 3 The pyrolytic carbon deposition thin-walled preform is subjected to a high-temperature graphitization treatment at 3000°C.

[0042] (3) The SiC ceramic matrix was densified using the CVI process, with trichloromethylsilane MTS (CH3SiCl3) as the reaction gas, H2 gas as the carrier gas, Ar gas as the dilution gas, the deposition temperature at 1000 °C, the reaction gas flow rate at 50 g / min, and the H2 flow rate at 0.20 m 3 / h, Ar gas flow rate is 0.30m 3 / h. Sedimentation time 100h.

[0043] (4) The PIP process is used to continue the densification of the SiC ceramic matrix, with an immersion temperature of 100°C, an immersion pressure of 1.5 MPa, and an immersion time of 1 hour; the curing temperature is 200°C, the curing pressure is 1.5 MPa, and the curing time is 1 hour; the high-temperature pyrolysis temperature is 1000°C, and the pyrolysis time is 2 hours, and the density of the prepared SiC ceramic matrix is ​​2.0 g / cm 3 Thin-walled ceramic-based composite materials with heat conduction function.

[0044] Example 2

[0045] A thin-walled ceramic-based composite material with heat conduction function and a preparation method thereof, wherein the specific steps are as follows:

[0046] (1) Shaanxi Tiance TC-22B 2K mesophase asphalt-based carbon fiber and PAN-based T700 12K fiber were used to prepare a thin-walled preform with heat conduction function. First, Shaanxi Tiance TC-22B 2K mesophase asphalt-based carbon fiber was widened to 16 mm, and PAN-based T700 12K fiber was widened to 24 mm. Then, a thin-walled preform was prepared using 2.5D weaving technology.

[0047] (2) The thin-walled preform is subjected to a high-temperature preheating treatment at 1800°C for 2 hours, and then a pyrolytic carbon interface layer is deposited on the surface of the preform fiber using the CVI method. The carbon source used is propylene, the carrier gas is nitrogen, and the deposition temperature is preferably 900°C. The density of the preform after pyrolytic carbon deposition is 1.00 g / cm 3 The preform after pyrolytic carbon deposition is subjected to a high-temperature graphitization treatment at 3200°C.

[0048] (3) The SiC ceramic matrix was densified using the CVI process, with trichloromethylsilane MTS (CH3SiCl3) as the reaction gas, H2 gas as the carrier gas, Ar gas as the dilution gas, the deposition temperature at 1500 °C, the reaction gas flow rate at 50 g / min, and the H2 flow rate at 0.15 m 3 / h, Ar gas flow rate is 0.35m 3 / h. Sedimentation time 90h.

[0049] (4) The PIP process was used to densify the SiC ceramic matrix. The immersion temperature was 80°C, the immersion pressure was 1.5 MPa, and the immersion time was 2 h. The curing temperature was 300°C, the curing pressure was 1.5 MPa, and the curing time was 2 h. The high-temperature pyrolysis temperature was 1000°C, and the pyrolysis time was 2 h. The density of the prepared SiC ceramic matrix was 1.98 g / cm 3 Thin-walled ceramic-based composite materials with heat conduction function.

[0050] While the foregoing detailed description has set forth various specific embodiments of the application, it is to be understood that the disclosure is not to be limited to the details of construction or the arrangement of parts as set forth in the foregoing description. The foregoing detailed description is to be considered in all respects only as illustrative and not as restrictive.

Claims

1. A method for preparing a thin-walled ceramic-based composite material with a heat-conducting function, characterized in that: The following steps are involved: (1) preparing a thin-walled preform of a mixed PAN-based fiber wide band and a mesophase pitch-based fiber wide band, and performing a high-temperature preheating treatment on the mixed PAN-based fiber wide band and the mesophase pitch-based fiber wide band; the thin-walled preform of the mixed PAN-based fiber wide band and the mesophase pitch-based fiber wide band is prepared by using the PAN-based fiber wide band and the mesophase pitch-based fiber wide band in combination with a 2.5D weaving technology; (2) depositing a pyrolytic carbon interface layer on the fiber surface of the thin-walled preform by chemical vapor deposition and subjecting it to high-temperature graphitization treatment; (3) The SiC ceramic matrix is ​​densified by chemical vapor deposition and precursor impregnation cracking on the carbon-deposited thin-walled preform after high-temperature graphitization treatment to obtain a thin-walled ceramic-based composite material with a heat-conducting function, wherein the thickness of the thin-walled ceramic-based composite material with a heat-conducting function is ≤1 mm.

2. The preparation method according to claim 1, wherein: Before performing step (2), the thin-walled preform is subjected to a high-temperature preheating treatment, wherein the temperature of the high-temperature preheating treatment is 1800-2000° C. and the holding time is 2-3 hours.

3. The preparation method according to claim 1, wherein: The carbon source used in the chemical vapor deposition method in step (2) is propylene, the carrier gas is nitrogen, the deposition temperature is 800-1100°C, and the deposition time is determined by the density of the thin-walled preform after the pyrolytic carbon is deposited; the density of the thin-walled preform after the pyrolytic carbon is deposited is 0.9-1.1 g / cm 3 .

4. The preparation method according to claim 1, wherein: The temperature of the high-temperature graphitization treatment in step (2) is 2400-3200°C.

5. The preparation method according to claim 1, wherein: The deposition process of the chemical vapor deposition method in step (3) uses trichloromethylsilane as the reaction gas, H2 gas as the carrier gas, Ar gas as the dilution gas, the deposition temperature is 1000-1100°C, the reaction gas flow rate is 50-100g / min, the H2 flow rate is 0.15-0.25m 3 / h, Ar gas flow rate is 0.2~0.4m 3 / h.

6. The preparation method according to claim 1, wherein: The deposition time of the chemical vapor deposition method in step (3) is 80 to 100 hours.

7. The preparation method according to claim 1, wherein: The precursor impregnation and cracking method in step (3) includes impregnation, curing and high-temperature cracking, and liquid polycarbosilane is used as the ceramic precursor. The impregnation temperature is 10-100°C, the impregnation pressure is 0.5-2MPa, and the impregnation time is 0.5-2h; the curing temperature is 100-350°C, the curing pressure is 0.5-2MPa, and the curing time is 0.5-2h; the high-temperature cracking temperature is 900-1200°C, and the cracking time is 2-4h.

8. The preparation method according to claim 1, wherein: The density of the thin-walled ceramic-based composite material with heat conduction function obtained in step (3) is 1.9-2.0 g / cm 3 .

9. A thin-walled ceramic-based composite material with heat conduction function prepared by the method according to any one of claims 1 to 8.