CN108840697A - A kind of carbon/carbon compound material honeycomb and preparation method thereof - Google Patents

Abstract

A carbon/carbon composite material honeycomb and a preparation method thereof belong to the technical field of carbon/carbon composite materials. The carbon/carbon composite material honeycomb includes a carbon fiber reinforcement and a carbon matrix covering the surface of the carbon fiber reinforcement, wherein the carbon fiber reinforcement is a honeycomb structure, and the honeycomb structure has continuous carbon fibers in the L direction, and the W direction Also has continuous carbon fiber. The carbon/carbon composite material honeycomb of the present invention has excellent thermal stability and mechanical properties, and meets the lightweight requirements of the aerospace field; the main performance parameters of the honeycomb meet the requirements of flat compressive strength ≥ 8MPa, flat compressive modulus ≥ 900MPa, and L-direction shear strength ≥6.7MPa, L-direction shear modulus ≥1500MPa, W-direction shear strength ≥4.5MPa, W-direction shear modulus ≥730MPa, thermal expansion coefficient 0～0.2×10 ^‑6 /K.

Description

A carbon/carbon composite material honeycomb and its preparation method

technical field

This patent relates to a low-density, high-stability, high-strength integral carbon/carbon composite material honeycomb for a high-precision observation platform, which belongs to the technical field of carbon/carbon composite materials.

Background technique

Traditional composite materials for spacecraft structures generally only require high specific strength, high specific modulus, etc., and do not have high requirements for dimensional stability. However, in the field of research and development of composite material structures for high-precision spacecraft such as satellites, composite materials with high stability, light weight, and high strength are an important development direction. Advanced countries have begun to study zero-expansion, high-stability composite material structures for spacecraft, which are mainly used for supporting structures of optical instruments such as space telescopes, supporting bases for gravity gradiometers, and antenna reflective panels. In order to ensure the working accuracy of high-precision optical instruments and detection equipment on spacecraft, it is necessary to provide a high-stability, high-strength lightweight composite material structure platform.

In the prior art, carbon/carbon composite blocks, carbon/silicon carbide composite blocks or carbon fiber reinforced resin-based honeycombs are usually used in the domestic aerospace field as the supporting structure of precision instruments to maintain good stability; due to carbon The carbon/carbon composite block or the carbon/silicon carbide composite block are all solid structures, which is not conducive to the lightweight requirements of the aerospace field; the carbon fiber reinforced resin-based honeycomb thermal expansion system is on the order of 10 ^-4 and has poor thermal stability.

Contents of the invention

In order to solve the problems existing in the prior art, the embodiment of the present invention provides a carbon/carbon composite material honeycomb and its preparation method. The carbon/carbon composite material honeycomb has excellent thermal stability and mechanical properties, and meets the requirements of light weight in the aerospace field. Require.

In order to realize the foregoing invention object, the present invention provides following technical scheme:

A carbon/carbon composite honeycomb, comprising a carbon fiber reinforcement and a carbon matrix covered on the surface of the carbon fiber reinforcement, wherein the carbon fiber reinforcement is a honeycomb structure, and the honeycomb structure has continuous carbon fibers in the L direction, and the W direction Also has continuous carbon fiber.

In an optional embodiment, the carbon fiber reinforcement is made of T300-1K, T300-3K, T300-6K, T300-12K, T700-6K, T700-12K, T800-6K or T800-12K polyacrylonitrile One or a combination of more than one of them.

In an optional embodiment, the honeycomb wall of the carbon fiber reinforced body has continuous fibers with a direction of 30-60°.

In an optional embodiment, the cell side length of the honeycomb is 2.75mm-15mm, and the thickness of the honeycomb wall is 0.17mm-2mm.

In an optional embodiment, the carbon/carbon composite material honeycomb density is 100kg/m ³ -220kg/m ³ .

A method for preparing a carbon/carbon composite material honeycomb, comprising the following steps:

Step 1, preparing a carbon fiber reinforced body of a honeycomb structure, in which the L direction has continuous carbon fibers, and the W direction also has continuous carbon fibers;

Step 2, using phenolic resin to impregnate and cure the carbon fiber reinforcement of the honeycomb structure to obtain a cured dimensional carbon fiber reinforcement;

Step 3. Carrying out carbonization and densification treatment on the solidified dimensional carbon fiber reinforcement to obtain a carbon/carbon composite material honeycomb.

In an optional embodiment, before performing carbonization treatment on the solidified dimensional carbon fiber reinforcement described in step 3, it also includes:

A mandrel is inserted into the honeycomb core of the cured dimensional carbon fiber reinforced body, and the side wall of the mandrel is provided with an airflow channel extending along the thickness direction of the honeycomb.

In an optional embodiment, the air flow channel is provided on the six side walls of each mandrel, and the width of the position where the air flow channel connects with the solidified dimensional carbon fiber reinforcement is the specified 60-80% of the width of the side walls of the mandrel, and 20-30% of the distance between the two side walls of the mandrel.

In an optional embodiment, the phenolic resin described in step 2 is a phenolic resin diluted with a volatile organic solvent, wherein the mass percentage of the volatile organic solvent is 10% to 50%

In an optional embodiment, the carbonization described in step 3 includes:

First, keep warm at 280-320°C for 1.5-3h, then at 540-560°C for 1.5-3h, then at 800-900°C for 2-4h, then drop to room temperature.

In an optional embodiment, the temperature is raised to 180-220°C at a heating rate of 40-60°C/h, to 280-320°C at a heating rate of 5-15°C/h, and to 280-320°C at a heating rate of 5-10°C/h Raise the temperature to 540-560°C at a heating rate of 5-10°C/h to 640-660°C at a heating rate of 10-20°C/h to 800-900°C at a rate of no more than 100°C/h cooling rate down to room temperature. In an optional embodiment, the densification treatment described in step 3 includes:

Densification treatment is carried out by chemical vapor deposition process, wherein the carbon source gas is one or more combinations of methane, propylene or propane, the ventilation rate is 5-50L/min, the pressure is 0.6-0.7kPa, and the deposition time is 100 -400h.

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

(1) The carbon/carbon composite material honeycomb provided by the embodiment of the present invention ensures that the carbon/carbon composite material honeycomb is not easy to delaminate and crack during the carbonization and densification process by making the carbon fiber reinforcement have continuous carbon fibers in both the L direction and the W direction , the densification process has excellent adaptability, and the prepared carbon/carbon composite honeycomb has excellent thermal stability and mechanical properties, and meets the lightweight requirements of the aerospace field;

(2) The main performance parameters of the honeycomb meet the requirements of flat compressive strength ≥ 8MPa, flat compressive modulus ≥ 900MPa, L-direction shear strength ≥ 6.7MPa, L-direction shear modulus ≥ 1500MPa, W-direction shear strength ≥ 4.5MPa, W-direction Shear modulus ≥ 730MPa, thermal expansion coefficient 0～0.2×10 ^-6 /K;

(3) Densification by chemical vapor deposition process to ensure efficient densification of the honeycomb near the size;

(4) The carbon/carbon honeycomb densification process is simple, the densification cycle is short, and it is easy to realize engineering application.

Description of drawings

Fig. 1 is the appearance diagram of a kind of carbon/carbon composite material honeycomb provided by the embodiment of the present invention;

Fig. 2 is a schematic diagram of the way of combining two carbon cloths when carbon cloth is used to prepare carbon fiber reinforced body provided by the embodiment of the present invention;

Fig. 3 is a schematic diagram of the structure of the graphite mandrel for densification provided by the embodiment of the present invention.

Detailed ways

The specific implementation manner of the present invention will be further explained below in conjunction with specific examples.

As shown in Figure 1, an embodiment of the present invention provides a carbon/carbon composite honeycomb, including a carbon fiber reinforcement and a carbon matrix covering the surface of the carbon fiber reinforcement, wherein the carbon fiber reinforcement is a honeycomb structure, and the In the honeycomb structure, the L direction has continuous carbon fibers, and the W direction also has continuous carbon fibers.

Specifically, in the embodiment of the present invention, the L direction and the W direction of the carbon fiber reinforced body honeycomb structure can be realized to have continuous fibers by splicing and sewing carbon cloth, wherein, the L direction is the continuous fiber in the cloth layer, and the W direction is the cloth layer. The stitching fibers between the layers, specifically, as shown in Figure 2, first cut the carbon cloth into a predetermined shape according to the honeycomb design size and mark the position to be stitched, then butt the adjacent carbon cloth, and the butt joint surface passes through the stitching line suture;

The carbon/carbon composite material honeycomb provided by the embodiment of the present invention ensures that the carbon fiber used as the carbon/carbon honeycomb skeleton has continuity in all directions inside the honeycomb by making the carbon fiber reinforced body have continuous carbon fibers in both the L direction and the W direction. The external load on the carbon/carbon honeycomb can be efficiently transferred between different honeycomb cells through continuous fibers, which fully improves the mechanical properties of the carbon/carbon honeycomb; the carbon/carbon composite material honeycomb provided by the embodiment of the present invention has excellent thermal stability and Mechanical properties, and meet the lightweight requirements of the aerospace field; the carbon/carbon composite honeycomb is not easy to delaminate and crack during the carbonization and densification process, and the densification process has excellent adaptability; the main performance parameters of the honeycomb meet the requirements of the flat compressive strength ≥ 8MPa, Weight ≥ 900MPa, L-direction shear strength ≥ 6.7MPa, L-direction shear modulus ≥ 1500MPa, W-direction shear strength ≥ 4.5MPa, W-direction shear modulus ≥ 730MPa, thermal expansion coefficient 0～0.2×10 ^-6 / K.

In an optional embodiment, the carbon fiber reinforcement is preferably made of T300-1K, T300-3K, T300-6K, T300-12K, T700-6K, T700-12K, T800-6K or T800-12K polyacrylonitrile One or more combinations of carbon fibers.

In an optional embodiment, the honeycomb wall of the carbon fiber reinforced body has continuous fibers with a direction of 30-60° to ensure that the carbon/carbon honeycomb has strong shear resistance.

In an optional embodiment, the cell side length of the honeycomb is 2.75 mm to 15 mm, and the honeycomb wall thickness is 0.17 mm to 2 mm. By optimizing the cell side length and wall thickness of the honeycomb, it is ensured that the honeycomb has a high The specific strength ensures that the honeycomb wall is smooth and flat, avoiding carbon deposition or demoulding damage to the honeycomb wall during the densification process due to the roughness of the honeycomb wall.

In an optional embodiment, the carbon/carbon composite material honeycomb has a density of 100kg/m ³ -220kg/m ³ , which ensures that the carbon/carbon honeycomb meets the requirements of the lightweight design and the mechanical performance index.

The embodiment of the present invention also provides a method for preparing a carbon/carbon composite material honeycomb, comprising the following steps:

Step 1, preparing a carbon fiber reinforced body of a honeycomb structure, in which the L direction has continuous carbon fibers, and the W direction also has continuous carbon fibers;

Specifically, in the embodiment of the present invention, the L-direction and W-direction of the carbon fiber reinforced body honeycomb structure can be realized to have continuous fibers by splicing and sewing carbon cloth. Specifically, as shown in FIG. The design size is cut into a predetermined shape and marked at the position that needs to be stitched, and then the two pieces of carbon cloth m are pasted and docked, and the butt joint surface is stitched through the stitching line n. After stitching, when the core mold is inserted in the unstitched part, after the dimension is cured After demoulding, the honeycomb structure as shown in Figure 2 can be obtained;

The carbon matrix includes resin carbon formed by resin carbonization and pyrolytic carbon formed by densification treatment (chemical vapor deposition).

Step 2, using phenolic resin to impregnate and cure the carbon fiber reinforcement of the honeycomb structure to obtain a cured dimensional carbon fiber reinforcement;

Specifically, in the embodiment of the present invention, the phenolic resin described in step 2 is a phenolic resin diluted with volatile organic solvents such as ethanol, ethyl acetate, methanol, acetone, etc., wherein the mass percentage of the volatile organic solvent is 10%- 50%; the curing described in step 2 is preferably heated to 60-80°C at a heating rate of 20-40°C/h, and kept for 1-3h; heated to 90-110°C at a heating rate of 5-20°C/h, Keep warm for 0.5-2h; heat up to 120-130°C at a heating rate of 5-20°C/h, and keep warm for 0.5-2h; heat up to 150-170°C at a heating rate of 5-20°C/h, and hold for 5-7h; The cooling rate of ≤25°C/h cools down to below 80°C, and then cools down freely;

Step 3. Carrying out carbonization and densification treatment on the solidified dimensional carbon fiber reinforcement to obtain a carbon/carbon composite material honeycomb.

In an optional embodiment, before performing carbonization treatment on the solidified dimensional carbon fiber reinforcement described in step 3, it also includes:

A mandrel is inserted into the honeycomb core of the cured dimensional carbon fiber reinforced body, and the side wall of the mandrel is provided with an air flow channel extending along the thickness direction d of the honeycomb. By setting the airflow channel, it is ensured that the carbon source gas can enter the interior of the honeycomb smoothly, and the efficient and uniform densification of the honeycomb wall is realized.

As shown in Figure 3, in an optional embodiment, the airflow channels are provided on the six side walls of each mandrel, and the airflow channels are in contact with the solidified dimensional carbon fiber reinforcement. The width a of the contact position is 60-80% of the width of the side walls of the mandrel, and the depth b is 20-30% of the distance between the two side walls of the mandrel. By controlling the size of the airflow channel, the carbon source gas flow into the airflow channel is ensured, and at the same time, the contact area between the honeycomb wall and the outer surface of the mandrel is minimized to facilitate demoulding after densification and reduce demoulding damage to the honeycomb wall.

In an optional embodiment, the carbonization described in step 3 includes: raising the temperature to 180-220°C at a heating rate of 40-60°C/h; raising the temperature to 280-320°C at a heating rate of 5-15°C/h , keep warm for 1.5-3h; heat up to 540-560°C at a heating rate of 5-10°C/h, and keep warm for 1.5-3h; heat up to 640-660°C at a heating rate of 5-10°C/h; Raise the temperature to 800-900°C at a heating rate of /h, and keep warm for 1.5-3 hours to complete the carbonization of the resin. Through this carbonization process, the medium-term heating rate is slow, which can reduce the deformation internal stress of the honeycomb during the carbonization process and ensure that the honeycomb is formed in a close-to-size manner. In an optional embodiment, the densification treatment described in step 3 includes: after completing the carbonization process in the deposition furnace, directly increase the temperature from the highest temperature of the carbonization process to 900-1000 °C at a heating rate of 10-20 °C/h , keep warm for 1-3 hours, start to feed carbon source gas, gas flow rate 5-50L/min, furnace pressure 0.6-0.7kPa, deposition time 100-400h, to ensure efficient densification of honeycombs in close size.

In this embodiment, the carbon/carbon composite material honeycomb in the above honeycomb embodiment can be prepared. For the specific description of the carbon/carbon composite material honeycomb, refer to the above honeycomb embodiment, which will not be repeated here.

Below are several specific embodiments of the present invention:

Example 1

This embodiment provides a carbon/carbon composite material honeycomb for satellites with an outline size of 200mm×200mm×80mm, a honeycomb cell side length of 5mm, and a honeycomb wall thickness of 0.8mm. The preparation method includes:

1) Use general-purpose T300-3K polyacrylonitrile-based carbon fibers to weave into plain carbon cloth with an area density of 240g/cm ³ , and a warp and weft density of 6 threads/cm×6 threads/cm. Then cut the carbon cloth into carbon cloth blocks of a certain specification according to the expanded size of the honeycomb wall; during the cutting process, the warp yarn direction is 0°, rotate counterclockwise to form +45° carbon cloth, and rotate clockwise to form -45° carbon cloth.

2) Lay the carbon cloth blocks in step 1) according to the designed layering sequence, and arrange the adjacent carbon cloths in the order of +45/-45 layering; stitch the carbon cloths in pairs, and stitch the spacing in the thickness direction of the honeycomb 4mm, the stitching distance in the L direction of the honeycomb is 5mm, the stitching line is T300-1K carbon fiber, the diameter of the stitching yarn guide tool is 1.3mm; after the carbon cloth is stitched and piled up to the number of layers required by the honeycomb product design, insert the hexagonal metal impregnation-curing tool and impregnate ethanol A phenolic resin solution with a mass content of 20%; demolded after heating and curing to form a carbon fiber reinforcement. ℃/h; 100℃ for 1h; 100℃～120℃, 10℃/h; 120℃ for 1h; 120℃～160℃, 10℃/h; 160℃ for 6h; 160℃～70℃, ≤25℃ /h; 70 ℃ ~ room temperature, free cooling.

3) According to the solidified dimensional carbon fiber reinforcement prepared in step 2), an all-carbon anti-deformation compact chemical tooling is prepared, and the tooling is composed of a graphite core mold and a clamping plate. The graphite mandrel has a prismatic structure, and grooves 1 are processed on each side wall to form airflow channels. The cross section of the graphite mandrel is a hexagonal structure as shown in Figure 3, wherein the grooves 1 and the solidified dimension The width a of the contact position of the carbon fiber reinforced body is 3 mm, and the depth b is 2 mm.

4) Assemble the full carbon tooling in step 3) on the solidified dimensional carbon fiber reinforcement in step 2), and place the solidified dimensional carbon fiber reinforcement with tooling vertically in a cylindrical vertical deposition furnace; The deposition furnace is heated up. The temperature rise curve is from room temperature to 200°C, 50°C/h; from 200°C to 300°C, 10°C/h; ; 550℃～650℃, 10℃/h; 650℃～850℃, 15℃/h; keep warm at 850℃ for 2 hours to complete resin carbonization; continue to heat up, 850℃～930℃, 15℃/h; keep warm at 930℃ for 2 hours ; Start to flow propylene, the gas flow rate is 20L/min, keep the pressure in the furnace at 0.6-0.7kPa, and the deposition time is 200h; after the deposition is completed, stop the gas flow. 930 ℃ ~ room temperature, free cooling.

6) Disassemble the all-carbon tooling in step 4), process the honeycomb to a predetermined size, and obtain the final product.

Through the process method of the present invention, the 200mm order carbon/carbon honeycomb is densified to a density of 0.19g/cm ³ through 200h chemical vapor deposition, and five samples are taken from different positions, and the density deviation is ±0.003g/cm ³ ; Flat compressive strength 10.28MPa, flat compressive modulus 1052MPa, L-direction shear strength 6.79MPa, L-direction shear modulus 1670MPa, W-direction shear strength 5.26MPa, W-direction shear modulus 831MPa, thermal expansion coefficient 0.18×10 ^{- 6} /K; the thickness of the honeycomb wall is 0.78mm-0.82mm, and there is no carbon deposit on the surface of the honeycomb wall; the distance between the opposite sides of 10 honeycomb cells is measured randomly at 8.63mm-8.71mm, and the deformation control effect of the cell is good.

Example 2

This embodiment provides a carbon/carbon composite material honeycomb with an outline size of 400mm×400mm×80mm, a honeycomb cell side length of 5mm, and a honeycomb wall thickness of 0.8mm. The preparation method includes:

1) Use general-purpose T300-3K polyacrylonitrile-based carbon fibers to weave into plain carbon cloth with an area density of 240g/cm ³ , and a warp and weft density of 6 threads/cm×6 threads/cm. Then cut the carbon cloth into carbon cloth blocks of a certain specification according to the expanded size of the honeycomb wall; during the cutting process, the warp yarn direction is 0°, rotate counterclockwise to form +45° carbon cloth, and rotate clockwise to form -45° carbon cloth.

2) Lay the carbon cloth blocks in step 1) according to the designed layering sequence, and arrange the adjacent carbon cloths in the order of +45/-45 layering; stitch the carbon cloths in pairs, and stitch the spacing in the thickness direction of the honeycomb 4mm, the stitching distance in the L direction of the honeycomb is 5mm, the stitching line is T300-1K carbon fiber, the diameter of the stitching yarn guide tool is 1.3mm; after the carbon cloth is stitched and piled up to the number of layers required by the honeycomb product design, insert the hexagonal metal impregnation-curing tool and impregnate ethanol A phenolic resin solution with a mass content of 20%; demolded after heating and curing to form a carbon fiber reinforcement. ℃/h; 100℃ for 1h; 100℃～120℃, 10℃/h; 120℃ for 1h; 120℃～160℃, 10℃/h; 160℃ for 6h; 160℃～70℃, ≤25℃ /h; 70 ℃ ~ room temperature, free cooling.

3) According to the solidified dimensional carbon fiber reinforcement prepared in step 2), an all-carbon anti-deformation compact chemical tooling is prepared, and the tooling is composed of a graphite core mold and a clamping plate. The graphite core is a prism structure, and grooves 1 are processed on each side wall to form an airflow channel. The cross section of the graphite core mold is a hexagonal structure as shown in Figure 3, wherein the groove 1 and the solidified dimension The width a of the contact position of the carbon fiber reinforced body is 3 mm, and the depth b is 2 mm.

4) Assemble the full carbon tooling in step 3) on the solidified dimensional carbon fiber reinforcement in step 2), and place the solidified dimensional carbon fiber reinforcement with tooling vertically in a cylindrical vertical deposition furnace; The deposition furnace is heated up. The temperature rise curve is from room temperature to 200°C, 50°C/h; from 200°C to 300°C, 10°C/h; ; 550℃～650℃, 10℃/h; 650℃～850℃, 15℃/h; keep warm at 850℃ for 2 hours to complete resin carbonization; continue to heat up, 850℃～930℃, 15℃/h; keep warm at 930℃ for 2 hours ; Start to flow propylene, the gas flow rate is 20L/min, keep the pressure in the furnace at 0.6-0.7kPa, and the deposition time is 200h; after the deposition is completed, stop the gas flow. 930 ℃ ~ room temperature, free cooling.

6) Disassemble the all-carbon tooling in step 4), process the honeycomb to a predetermined size, and obtain the final product.

Through the process method of the present invention, the carbon/carbon honeycomb of the order of 400mm is densified to a density of 0.185g/cm ³ through 200h chemical vapor deposition, and five samples are taken from different positions, and the density deviation is ±0.005g/cm ³ ; test its Flat compressive strength 10.03MPa, flat compressive modulus 1027MPa, L-direction shear strength 6.55MPa, L-direction shear modulus 1606MPa, W-direction shear strength 5.01MPa, W-direction shear modulus 798MPa, coefficient of thermal expansion 0.18×10 ^{- 6} /K; the thickness of the honeycomb wall is 0.79mm-0.83mm, and there is no carbon deposit on the surface of the honeycomb wall; the distance between the opposite sides of 10 honeycomb cells is measured randomly at 8.58mm-8.64mm, and the deformation control effect of the cell is good. At the same time, the size of the honeycomb is similar to that of a 200mm honeycomb, and the carbon/carbon honeycomb and its preparation method described in this patent have good stability.

Example 3

This embodiment provides a carbon/carbon composite material honeycomb with an outline size of 400mm×400mm×50mm, a honeycomb core cell side length of 4mm, and a honeycomb wall thickness of 0.3mm. The preparation method includes:

1) Use general-purpose T700-12K polyacrylonitrile-based carbon fiber to weave into a spread cloth with an area density of 200g/cm ³ and a fiber spread width of 8mm. Then cut the carbon cloth into carbon cloth blocks of a certain specification according to the expanded size of the honeycomb wall; during the cutting process, the warp yarn direction is 0°, rotate counterclockwise to form +45° carbon cloth, and rotate clockwise to form -45° carbon cloth.

2) Lay the carbon cloth blocks in step 1) according to the designed layering sequence, and arrange the adjacent carbon cloths in the order of +45/-45 layering; stitch the carbon cloths in pairs, and stitch the spacing in the thickness direction of the honeycomb 3mm, the stitching distance in the L direction of the honeycomb is 4mm, the stitching line is T300-1K carbon fiber, and the diameter of the stitching yarn guide tool is 1.3mm; after the carbon cloth is stitched and piled up to the number of layers required by the honeycomb product design, insert the hexagonal metal impregnation-curing tool and impregnate ethanol A phenolic resin solution with a mass content of 15%; demolded after heating and curing to form a carbon fiber reinforcement. ℃/h; 100℃ for 1h; 100℃～120℃, 10℃/h; 120℃ for 1h; 120℃～160℃, 10℃/h; 160℃ for 6h; 160℃～70℃, ≤25℃ /h; 70 ℃ ~ room temperature, free cooling.

3) According to the solidified dimensional carbon fiber reinforcement prepared in step 2), an all-carbon anti-deformation compact chemical tooling is prepared, and the tooling is composed of a graphite core mold and a clamping plate. The graphite core is a prism structure, and grooves 1 are processed on each side wall to form an airflow channel. The cross section of the graphite core mold is a hexagonal structure as shown in Figure 3, wherein the groove 1 and the solidified dimension The width a of the contact position of the carbon fiber reinforced body is 2.5 mm, and the depth b is 1.5 mm.

4) Assemble the full carbon tooling in step 3) on the solidified dimensional carbon fiber reinforcement in step 2), and place the solidified dimensional carbon fiber reinforcement with tooling vertically in a cylindrical vertical deposition furnace; The deposition furnace is heated up. The temperature rise curve is from room temperature to 200°C, 50°C/h; from 200°C to 300°C, 10°C/h; ; 550℃～650℃, 10℃/h; 650℃～850℃, 15℃/h; keep warm at 850℃ for 2 hours to complete resin carbonization; continue to heat up, 850℃～930℃, 15℃/h; keep warm at 930℃ for 2 hours ; Start to pass propylene, the gas flow rate is 20L/min, keep the pressure in the furnace at 0.6-0.7kPa, and the deposition time is 300h; after the deposition is completed, stop the ventilation. 930 ℃ ~ room temperature, free cooling.

6) Disassemble the all-carbon tooling in step 4), process the honeycomb to a predetermined size, and obtain the final product.

Through the process method of the present invention, the carbon/carbon honeycomb of the order of 400mm is densified to a density of 0.18g/cm ³ through 300h chemical vapor deposition, and five samples are taken from different positions, and the density deviation is ±0.005g/cm ³ ; Flat compressive strength 8.93MPa, flat compressive modulus 967MPa, L-direction shear strength 6.32MPa, L-direction shear modulus 1583MPa, W-direction shear strength 4.89MPa, W-direction shear modulus 795MPa, coefficient of thermal expansion 0.16×10 ^{- 6} /K; the thickness of the honeycomb wall is 0.29mm-0.33mm, and there is no carbon deposit on the surface of the honeycomb wall; the distance between the opposite sides of 10 honeycomb cells is measured randomly at 6.90mm-7.05mm, and the deformation control effect of the cell is good.

The content that is not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims (12)

1. a kind of carbon/carbon compound material honeycomb, which is characterized in that including carbon fiber reinforcement and be covered on the fibre reinforced The carbon base body in body surface face, wherein the carbon fiber reinforcement be honeycomb, and in the honeycomb L to continuous carbon fiber Dimension, W is to also with continuous carbon fibre.

2. carbon/carbon compound material honeycomb according to claim 1, which is characterized in that the carbon fiber reinforcement is by T300- 1K, T300-3K, T300-6K, T300-12K, T700-6K, T700-12K, T800-6K or T800-12K polyacrylonitrile-radical carbon fiber One of dimension or more than one combinations are made.

3. carbon/carbon compound material honeycomb according to claim 1, which is characterized in that the honeycomb of the carbon fiber reinforcement With the continuous fiber in 30-60 ° of direction on wall.

4. carbon/carbon compound material honeycomb according to claim 1, which is characterized in that the cellular core lattice side length is 2.75mm~15mm, honeycomb wall is with a thickness of 0.17mm~2mm.

5. carbon/carbon compound material honeycomb according to claim 1, which is characterized in that density 100kg/m³~220kg/ m³。

6. a kind of cellular preparation method of carbon/carbon compound material, which is characterized in that include the following steps：

Step 1, the carbon fiber reinforcement for preparing honeycomb, L is to continuous carbon fibre in the honeycomb, and W is to also having There is continuous carbon fibre；

Step 2 is impregnated using carbon fiber reinforcement of the phenolic resin to the honeycomb, is solidified, and solidification d type is obtained Carbon fiber reinforcement；

Step 3 is carbonized to the carbon fiber reinforcement for solidifying d type, densification, and carbon/carbon compound material bee is obtained Nest.

7. the cellular preparation method of carbon/carbon compound material according to claim 6, which is characterized in that described in step 3 Before carrying out carbonization treatment to the carbon fiber reinforcement for solidifying d type, further include：

Core model is inserted into the honeycomb core lattice of the carbon fiber reinforcement for solidifying d type, the core model side wall is equipped with along honeycomb The airflow channel that thickness direction extends.

8. the cellular preparation method of carbon/carbon compound material according to claim 7, which is characterized in that each core model Six side walls on be equipped with the airflow channel, and the airflow channel connects with the carbon fiber reinforcement for solidifying d type The width of position is the 60-80% of the core model sidewall width, and depth is the distance of opposite two side walls of the core model 20-30%.

9. the cellular preparation method of carbon/carbon compound material according to claim 6, which is characterized in that phenol described in step 2 Urea formaldehyde is the diluted phenolic resin of volatile organic solvent, wherein the mass percent of the volatile organic solvent is 10% ~50%.

10. the cellular preparation method of carbon/carbon compound material according to claim 6, which is characterized in that described in step 3 Carbonization, including：

First at 280~320 DEG C, 1.5~3h is kept the temperature, then at 540~560 DEG C, keeps the temperature 1.5~3h, later at 800-900 DEG C, 2-4h is kept the temperature, room temperature is down to.

11. the cellular preparation method of carbon/carbon compound material according to claim 10, which is characterized in that with 40-60 DEG C/h Heating rate be warming up to 180~220 DEG C, 280~320 DEG C are warming up to the heating rate of 5-15 DEG C/h, with 5~10 DEG C/h's Heating rate is warming up to 540~560 DEG C, is warming up to 640~660 DEG C with the heating rate of 5~10 DEG C/h；With 10-20 DEG C/h's Heating rate is warming up to 800-900 DEG C, is down to room temperature with the rate of temperature fall no more than 100 DEG C/h.

12. the cellular preparation method of carbon/carbon compound material according to claim 6, which is characterized in that described in step 3 Densification, including：

Carry out densification using gas-phase deposition is learned, wherein carbon-source gas be one of methane, propylene or propane or More than one combinations, Ventilation Rate is 5~50L/min, pressure is 0.6~0.7kPa, sedimentation time 100-400h.