High thermal conductive cf / si c-zr b2-diamond composite material and preparation method thereof

Abstract

The application relates to a composite material preparation method, in particular to a high-thermal-conductivity C f / SiC-ZrB2-Diamond composite material preparation method and high-thermal-conductivity C f / SiC-ZrB2-Diamond composite material, which solves the problems that diamond particles in a preform lack protection in the prior art, and that the porosity of a C / SiC-Diamond composite material is high, which is not conducive to improving the thermal conductivity of the composite material. The preparation method of the application deposits a pyrolytic carbon layer and a SiC layer on the surface of a carbon fiber preform, then forms a shielding layer containing ultrahigh-temperature ceramics on the surface of the fiber bundle by impregnating a resin-based slurry, then introduces diamond particles by combining vacuum pressure impregnation and ultrasonic impregnation, then prepares a silicon carbide protective layer on the surface of the impregnated particles, and then introduces phenolic carbon by using modified phenolic resin, so that a high-thermal-conductivity C f / SiC-ZrB2-Diamond composite material is prepared through a penetration reaction.

Description

Technical Field

[0001] This invention relates to a method for preparing composite materials, specifically to a high thermal conductivity C f Preparation method and high thermal conductivity C of SiC-ZrB2-Diamond composite material f / SiC-ZrB2-Diamond composite material. Background Technology

[0002] Ultra-high temperature modified continuous carbon fiber reinforced silicon carbide (C f C / ZrB2–SiC ceramic matrix composites possess excellent high-temperature resistance, oxidation resistance, ablation resistance, and mechanical properties, and are mainly used in thermal protection components above 2000℃, considered ideal candidate materials for hot-end components of future aerospace vehicles. However, their thermal conductivity is poor. In the literature "Sufang Tang, Jingyi Deng *, Shijun Wang, Wenchuan Liu, Comparison of thermal and ablation behaviors of C / SiC composites and C / ZrB2–SiC composites[J]. Corrosion Science 51 (2009) 54–61", the ultra-high temperature modified continuous carbon fiber reinforced silicon carbide ceramic matrix composite used is a C / ZrB2–SiC composite, whose room temperature thermal conductivity in the thickness direction is less than 12 W / (m·K), seriously affecting its service life and range. When the component is in a harsh thermal stress environment during service, due to the poor thermal conductivity of the material, thermal protection can only be achieved through passive ablation of the material matrix. As the material ablates, the thermal protection effect weakens, and the matrix will also crack or even fail. To address the issue of poor thermal conductivity in ultra-high temperature modified continuous carbon fiber reinforced silicon carbide ceramic matrix composites, matrix modification can be used to improve the thermal conductivity of the material, enabling rapid heat conduction during service, thereby increasing the material's operating temperature range and ablation resistance.

[0003] The thermal conductivity of diamond depends on the propagation of carbon atom vibrations. Due to the high energy of the covalent bonds between its atoms, the energy transfer of atomic vibrations is fast and the attenuation is small. Its thermal conductivity at room temperature can reach up to 2000 W / (m·K). In addition, diamond has a low coefficient of thermal expansion and density, and its strength will not be affected by thermal stress in high-temperature environments. Therefore, modifying ultra-high temperature modified continuous carbon fiber reinforced silicon carbide ceramic matrix composites with diamond can effectively improve the thermal conductivity of the materials.

[0004] Chinese patent CN109704776A describes a method of introducing diamond into a preform by laser drilling combined with impregnation, followed by the preparation of a C / SiC composite material using RMI technology. This method effectively improves the thermal conductivity of the composite material, but laser drilling damages the structure of the composite material and affects its strength. Furthermore, in the literature "Jingxin Li, Yongsheng Liu, ChaoChen, Yu Pan, Jing Wang, Ning Wang, Effect of diamond content on microstructure and properties of C / SiC-diamond composites[J]. Diamond and Related Materials, 2020, 107902", Jingxin Li et al. introduced diamond particles with a diameter of 1 μm into the preform as a thermally conductive filler through repeated vacuum impregnation. They then prepared a C / SiC-Diamond composite with a thermal conductivity of 14.68 W / (m·K) using reactive infiltration, which is nearly twice that of C / SiC composites prepared by chemical vapor infiltration (CVI) (thermal conductivity 5-6 W / (m·K)). However, the above method lacks protection for the diamond particles inside the preform before reactive infiltration (RMI), and the porosity is relatively high after RMI, which is not conducive to improving the thermal conductivity of the composite material. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies, such as the lack of protection for diamond particles inside the preform and the high porosity of C / SiC-Diamond composites, which hinders the improvement of the composite's thermal conductivity. Therefore, this invention provides a high thermal conductivity C... f Preparation method and high thermal conductivity C of SiC-ZrB2-Diamond composite material f / SiC-ZrB2-Diamond composite material.

[0006] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0007] A high thermal conductivity C f The preparation method of SiC-ZrB2-Diamond composite material is characterized by the following steps:

[0008] S1, a pyrolytic carbon layer and a SiC layer are sequentially deposited on the fabricated preform to obtain a semi-dense porous C f / SiC preform;

[0009] S2, ZrB2 particles or SiC particles are added to a phenolic resin solution and ball-milled to obtain the first slurry;

[0010] S3, using the first slurry to process the semi-dense porous C obtained in step S1. f / SiC preforms are sequentially subjected to vacuum pressure impregnation, curing and pyrolysis treatment;

[0011] S4, using the second slurry, the preform treated in step S3 is subjected to ultrasonic impregnation, curing and pyrolysis treatment in sequence to obtain a preform filled with ultra-high temperature ceramic and diamond matrix; the second slurry is obtained by adding ZrB2 particles and diamond particles to phenolic resin solution and mixing them evenly.

[0012] S5, a silicon carbide protective layer containing diamond particles is prepared on the surface of the ultra-high temperature ceramic and diamond matrix filled in the preform.

[0013] S6, the preform treated in step S5 is immersed in a phenolic resin solution modified with metal salt, then removed and carbonized to obtain a C / SiC-ZrB2-Diamond-C porous preform; the metal salt is a nickel-containing metal salt or a copper-containing metal salt.

[0014] S7, the C / SiC-ZrB2-Diamond-C porous preform obtained in step S6 is subjected to a liquid silicon infiltration reaction to obtain C with high thermal conductivity. f The SiC-ZrB2-Diamond composite material was successfully prepared.

[0015] Furthermore, step S5 specifically includes:

[0016] S5.1, 2-5 vol.% of 3-5 μm diamond particles are added to liquid polycarbosilane and stirred and dispersed to obtain a third slurry. Under vacuum conditions, the preform obtained in step S4 is immersed in the third slurry and the vacuum conditions are maintained for 0.5-1 hours. Then, pressure is applied and the preform is taken out after being held at 0.5 MPa-1.4 MPa for 0.5-1 hours.

[0017] S5.2, the preform treated in step S5.1 is cured in a vacuum environment at a temperature of 120-180℃ for 2-6 hours, and then subjected to pyrolysis treatment by holding at 900-1200℃ in a vacuum environment for 1-3 hours.

[0018] Furthermore, step S6 specifically includes:

[0019] S6.1, a phenolic resin solution with a mass fraction of 20%-50% is prepared using phenolic resin powder and its solvent, and a metal salt with a mass fraction of 1%-5% of the phenolic resin powder is added to it and stirred until the metal salt is completely dissolved to obtain a fourth slurry; the solvent is ethanol or acetone; the metal salt is nickel chloride, copper chloride, nickel nitrate or copper nitrate.

[0020] S6.2 Under vacuum conditions, the preform treated in step S5 is immersed in the fourth slurry and the vacuum conditions are maintained for 0.5-1 hour. Then, pressure is applied and the preform is taken out after being held at 0.5MPa-1.4MPa for 0.5-1 hour.

[0021] S6.3, the preform treated in step S6.2 is cured at 100-150℃ for 2-6 hours, and then subjected to pyrolysis treatment at 900-1200℃ in a vacuum environment for 1-3 hours;

[0022] S6.4, repeat steps S6.2 to S6.3 for 1-3 rounds, and then heat-treat the preform at 1500-1600℃ in a vacuum environment for 1-3 hours to obtain a C / SiC-ZrB2-Diamond-C porous preform.

[0023] Furthermore, step S7 specifically includes:

[0024] The C / SiC-ZrB2-Diamond-C porous preform obtained in step S6 was coated with silicon powder and then wrapped with graphite paper. The C / SiC-ZrB2-Diamond-C porous preform was then placed in a silicon infiltration furnace and subjected to liquid silicon infiltration reaction at 1500-1600℃ under vacuum for 30-120 minutes to obtain a C / SiC-ZrB2-Diamond composite material with high thermal conductivity, thus completing the preparation.

[0025] Furthermore, step S3 specifically includes:

[0026] S3.1, Under vacuum conditions, the semi-dense porous C obtained in step S1 is... f The SiC preform is immersed in the first slurry and impregnated under vacuum for 0.5-1 hour, then pressurized and held at 0.5MPa-1.4MPa for 0.5-1 hour before being removed.

[0027] S3.2, the impregnated preform is cured at 100-150℃ for 2-6 hours, and then subjected to pyrolysis treatment by holding at 900-1200℃ in a vacuum environment for 1-3 hours.

[0028] Furthermore, step S4 specifically includes:

[0029] S4.1 Under vacuum conditions, the preform treated in step S3.2 is immersed in the second slurry and kept for 0.5-1 hour. The preform and the second slurry are then placed together in an ultrasonic disperser for ultrasonic impregnation and stirring for 10-30 minutes. The preform and the second slurry are then transferred together to a pressure impregnation tank, sealed and pressurized, and kept at 0.5MPa-1.4MPa for 0.5-1 hour before being removed. The second slurry is obtained by adding ZrB2 particles and diamond particles to a phenolic resin solution and mixing them evenly.

[0030] S4.2, the preform treated in S4.1 is cured at 100-150℃ for 2-6 hours, and then subjected to pyrolysis treatment at 900-1200℃ in a vacuum environment for 1-3 hours to obtain a preform filled with ultra-high temperature ceramic and diamond matrix.

[0031] Further, in step S4, the preparation method of the second slurry is as follows:

[0032] Phenolic resin powder and its solvent were weighed according to the specified ratio to prepare a phenolic resin solution with a mass fraction of 15%-30%, using ethanol or acetone as the solvent. ZrB2 particles with a particle size of 2-5 μm and diamond particles with a particle size of 3-6 μm were added to the phenolic resin solution. The mixture was stirred for 1-1.5 hours, followed by ultrasonic treatment for 1-1.5 hours. This stirring and ultrasonic treatment process was repeated to obtain a second slurry. The volume ratio of ZrB2 particles to diamond particles was 1:1, and the total volume of ZrB2 particles and diamond particles accounted for 6-12 vol.% of the total volume of the second slurry.

[0033] In step S1, the thickness of the pyrolytic carbon layer is 300-600 nm; the thickness of the SiC layer is 1-4 μm.

[0034] In step S2, the ZrB2 or SiC has a particle size of 0.1-1 μm and a mass of 2%-15% of the phenolic resin solution; the phenolic resin solution has a mass fraction of 10%-20% and its solvent is ethanol or acetone.

[0035] Furthermore, in step S1, the thickness of the pyrolytic carbon layer is 500 nm, and the thickness of the SiC layer is 2-3 μm;

[0036] In step S2, the phenolic resin solution has a mass fraction of 15%, and ZrB2 particles with a particle size of 0.5 μm and a mass of 5% of the phenolic resin solution are added to the phenolic resin solution.

[0037] In step S3.1, maintain the vacuum condition for 0.5 hours, then pressurize and hold at 0.8 MPa for 0.7 hours before removing;

[0038] In step S3.2, the impregnated preform is cured at 120°C for 4 hours, and then subjected to pyrolysis treatment by holding at 1000°C in a vacuum environment for 2 hours.

[0039] In step S4.1, the preform treated in step S3.2 is immersed in the second slurry and kept for 0.5 hours. The preform and the second slurry are placed together in an ultrasonic disperser for ultrasonic impregnation and stirring for 20 minutes. The preform and the second slurry are then transferred to a pressure impregnation tank, sealed and pressurized, and taken out after being pressurized at 0.9 MPa for 0.5 hours.

[0040] In step S4.2, the preform treated in S4.1 is cured at 120°C for 4 hours, and then subjected to pyrolysis treatment at 1100°C for 2 hours in a vacuum environment.

[0041] Further, in step S5.1, 4 vol.% of 4 μm diamond particles are added to liquid polycarbosilane; the preform obtained in step S4 is immersed in the third slurry, and vacuum conditions are maintained for 0.6 hours, followed by pressurization, and the preform is removed after being held at 0.8 MPa for 0.6 hours.

[0042] In step S5.2, the solidification is carried out for 3 hours at a temperature of 150°C, followed by pyrolysis treatment at 1000°C in a vacuum environment for 2 hours.

[0043] In step S6.1, the phenolic resin solution has a mass fraction of 30%, and the metal salt is nickel nitrate, which has a mass of 2% of the phenolic resin powder.

[0044] In step S6.2, the vacuum condition is maintained for 0.6 hours, followed by pressurization and pressure maintenance at 0.8 MPa for 0.7 hours;

[0045] In step S6.3, the preform treated in step S6.2 is cured at 120°C for 3 hours, and then subjected to pyrolysis treatment at 1000°C for 2 hours in a vacuum environment;

[0046] In step S6.4, repeat steps S6.2 to S6.3 twice, and then heat-treat the preform at 1550°C for 2 hours in a vacuum environment.

[0047] In step S7, the liquid silicon infiltration reaction is carried out in a vacuum environment at 1500℃ for 120 minutes.

[0048] Meanwhile, the present invention provides the above-mentioned high thermal conductivity C f High thermal conductivity C obtained by the / SiC-ZrB2-Diamond composite material preparation method f / SiC-ZrB2-Diamond composite material.

[0049] The beneficial effects of this invention are:

[0050] 1. This invention has high thermal conductivity C f The preparation method of C / SiC-ZrB2-Diamond composite material involves impregnating the fiber bundle with a phenolic resin solution to form a resin-based slurry. This process attaches an ultra-high temperature ceramic layer composed of submicron-sized ZrB2 particles or silicon carbide particles to the surface of the fiber bundle, which can effectively alleviate the erosion of the fiber bundle by the molten metal. The resulting high thermal conductivity C / SiC-ZrB2-Diamond composite material has a strength of 257 MPa, ensuring good thermal conductivity while maintaining strength.

[0051] 2. The present invention has high thermal conductivity C f The preparation method of the / SiC-ZrB2-Diamond composite material combines vacuum pressure impregnation and ultrasonic impregnation to introduce 2-5μm ZrB2 particles and 3-6μm diamond particles into the preform, precisely constructing a thermally conductive microstructure with large-sized diamond particles and ZrB2 particles as the framework. The diamond particles and ZrB2 particles are dispersed through the ultrasonic impregnation process to prevent their sedimentation, thereby forming a diffusely distributed ultra-high temperature ceramic and diamond matrix.

[0052] 3. The present invention has high thermal conductivity C f The preparation method of the / SiC-ZrB2-Diamond composite material involves adding diamond particles to liquid polycarbosilane (LPCS) as a high thermal conductivity phase. The SiC layer (PIP-SiC layer) obtained by the precursor conversion method forms a silicon carbide protective layer containing diamond particles on the surface of diamond and ZrB2. This not only inhibits the erosion of diamond particles by the molten metal, but also further increases the diamond content in the matrix, which can effectively improve the thermal conductivity of the composite material.

[0053] 4. The present invention has high thermal conductivity C f The preparation method of the / SiC-ZrB2-Diamond composite material involves adding a metal salt to a phenolic resin solution to modify the phenolic resin. The modified phenolic resin is then carbonized through pyrolysis treatment. D / I G The significant decrease indicates a substantial increase in graphitization rate. Therefore, using the modified phenolic resin as the carbon source for subsequent infiltration reaction (RMI) can effectively reduce the reaction rate of metal melt and resin conversion to glassy carbon, ultimately leading to the preparation of high thermal conductivity C through RMI. f The thermal conductivity of the SiC-ZrB2-Diamond composite material reaches 21.64 W / (m·K).

[0054] 5. The present invention has high thermal conductivity C fThe preparation method of / SiC-ZrB2-Diamond composite material involves heat treatment at 1500-1600℃ in a vacuum environment before RMI, which can effectively open the closed pores caused by the previous process (curing and cracking of modified phenolic resin, precursor conversion method) and help to densify the reaction melt infiltration. Attached Figure Description

[0055] Figure 1 These are microscopic morphology images of the preform obtained in step four of embodiment one of the present invention; wherein, (a) is a microscopic morphology image magnified 150 times, and (b) is a microscopic morphology image magnified 2000 times.

[0056] Figure 2 The high thermal conductivity C obtained in Embodiment 1 of this invention f Flexural strength diagram of SiC-ZrB2-Diamond composite material;

[0057] Figure 3 This is a microscopic morphology image of the preform obtained in step nine of embodiment one of the present invention;

[0058] Figure 4 The comparison is between the infrared spectra of the modified phenolic resin after carbonization in step 12 of Embodiment 1 of the present invention and the phenolic resin before modification after carbonization; wherein, (a) is the infrared spectrum of the phenolic resin before modification after carbonization, and (b) is the infrared spectrum of the modified phenolic resin after carbonization in Embodiment 1 of the present invention.

[0059] Figure 5 These are microscopic images of the high thermal conductivity C / SiC-ZrB2-Diamond composite material obtained in Example 1 of the present invention, wherein (a) is a microscopic image magnified 500 times and (b) is a microscopic image magnified 1000 times. Detailed Implementation

[0060] Example 1

[0061] This invention employs ultrasonic impregnation to introduce ZrB2 and diamond particles into a semi-dense fine-woven carbon fiber preform. A protective layer of silicon carbide and carbon is formed on the diamond surface using polycarbosilane and modified phenolic resin. Liquid-phase silicating channels are constructed through particle size and solid content gradation. Finally, C is prepared via RMI. f The SiC-ZrB2-Diamond composite material has a thermal conductivity of 21.64 W / (m·K).

[0062] This invention provides a high thermal conductivity C f The preparation method of the / SiC-ZrB2-Diamond composite material specifically includes the following steps:

[0063] Step 1: A pyrolytic carbon layer with a thickness of 300-600 nm is deposited on a finely braided carbon fiber preform using the CVI process. Then, a SiC layer is deposited on the pyrolytic carbon layer using the CVI process, resulting in a semi-dense porous carbon fiber preform. f The preform is composed of SiC. To ensure the strength of the preform, the thickness of the SiC layer is typically 1~4μm.

[0064] In this embodiment, the thickness of the pyrolytic carbon layer is 500 nm, and the thickness of the SiC layer is 2-3 μm.

[0065] Step 2: Weigh the phenolic resin powder and its solvent according to the specified ratio to prepare a 15% (w / w) phenolic resin solution. Add ZrB2 particles with a particle size of 0.5 μm, accounting for 5% (w / w) of the phenolic resin solution, to the prepared phenolic resin solution. Ball mill for 12 hours to obtain the first slurry. The solvent for the phenolic resin powder is ethanol.

[0066] Step 3: Suspend the preform obtained in Step 1 above the first slurry in a pressure impregnation tank and create a vacuum. Then, immerse the preform in the first slurry for impregnation, maintaining the vacuum condition for 0.5 hours. Subsequently, pressurize and maintain the pressure at 0.8 MPa for 0.7 hours before removing it. The pressurization is usually done using argon, nitrogen, or air.

[0067] Step four: The impregnated preform is cured at 120℃ for 4 hours, followed by pyrolysis treatment at 1000℃ in a vacuum environment for 2 hours. The resulting preform is as follows. Figure 1 As shown in (b), the carbon fiber surface is coated with resin carbon obtained by pyrolysis of phenolic resin and ZrB2 (uhtc particles). Figure 1 (a) shows that there is no blockage in its pores, which facilitates the subsequent filling of ultra-high temperature ceramic and diamond matrix.

[0068] By adjusting the appropriate concentration of the phenolic resin solution, the particle size and mass fraction of ZrB2 particles, a first slurry of suitable concentration is prepared. The viscosity of the phenolic resin solution allows for the formation of a uniformly distributed resin-carbon-ZrB2 shielding layer on the fiber bundles within the preform during impregnation, effectively mitigating metal melt corrosion and resulting in higher strength. In other embodiments of the invention, the ZrB2 particles in step two can also be replaced with materials such as SiC to prepare the corresponding shielding layer.

[0069] Step 5: Weigh the phenolic resin powder and its solvent according to the formula, and prepare a phenolic resin solution with a mass fraction of 15%. Add ZrB2 particles with a particle size of 4μm and diamond particles with a particle size of 4μm to the prepared phenolic resin solution, stir for 1 hour, and then sonicate for 1 hour. Repeat the stirring and sonication once to obtain the second slurry. The volume ratio of ZrB2 particles to diamond particles is 1:1, and the total volume of ZrB2 particles and diamond particles accounts for 10 vol.% of the total volume of the second slurry.

[0070] Step Six: Place the second slurry in a beaker, then place the beaker in a pressure impregnation tank. Suspend the preform obtained in Step Four above the second slurry. Seal the pressure impregnation tank and evacuate it. Immerse the preform in the second slurry and maintain the vacuum condition for 0.5 hours. Then, remove the preform, including the beaker, and place it in an ultrasonic disperser for ultrasonic impregnation and stirring for 20 minutes. Transfer the preform, including the beaker, to the pressure impregnation tank, seal it, and pressurize it. Hold the pressure at 0.9 MPa for 0.5 hours, then remove it.

[0071] Step 7: The preform treated in step 6 is cured at 120°C for 4 hours, and then subjected to pyrolysis treatment at 1100°C for 2 hours in a vacuum environment, thereby achieving the filling of the pores with a diffusely distributed ultra-high temperature ceramic and diamond matrix.

[0072] Step 8: Add 4 vol.% of 4 μm diamond particles to liquid polycarbosilane (LPCS), stir and disperse to obtain the third slurry. Suspend the preform treated in step 7 above the third slurry in a pressure impregnation tank and evacuate. Then immerse the preform in the third slurry and maintain the vacuum condition for 0.6 hours. Subsequently, pressurize and maintain the pressure at 0.8 MPa for 0.6 hours before removing it.

[0073] Step nine: The preform treated in step eight is placed in a vacuum environment and cured at 150 ℃ for 3 hours. Then, it is subjected to a pyrolysis treatment at 1000 ℃ in a vacuum environment for 2 hours to convert the precursor into a silicon carbide protective layer containing diamond particles. The resulting preform structure is as follows: Figure 3 As shown, the slurry-impregnated particles are prepared in steps five to seven and include diamond and ZrB2.

[0074] Step 10: Weigh the phenolic resin powder and its solvent according to the ratio, prepare a phenolic resin solution with a mass fraction of 30%, weigh 2% nickel nitrate of phenolic resin powder and add it to the prepared phenolic resin solution, ultrasonically disperse for 30 minutes and then continue stirring for 3 hours until the metal salt is completely dissolved to obtain the fourth slurry.

[0075] Step 11: In the pressure impregnation tank, the preform treated in step 9 is suspended above the fourth slurry and a vacuum is drawn. Then the preform is immersed in the fourth slurry and the vacuum condition is maintained for 0.6 hours. Subsequently, it is pressurized and pressure is maintained at 0.8 MPa for 0.7 hours before being removed.

[0076] Step 12: The preform treated in Step 11 is cured at 120℃ for 3 hours, followed by pyrolysis treatment at 1000℃ in a vacuum environment for 2 hours. Infrared detection is then performed to obtain the infrared spectra of the phenolic resin after treatments in Steps 10 to 12, as shown below. Figure 4 As shown in (b), where I D / I G The ratio of the intensity of the D-peak to the G-peak in the Raman characteristic peaks of carbon atoms, compared to Figure 4 As can be seen from (a), the present invention modifies the phenolic resin by adding a metal salt and then carbonizes it, and its I D / I G The graphitization rate is significantly reduced. Therefore, modifying the phenolic resin before carbonization significantly improves the graphitization rate.

[0077] Step thirteen: Repeat steps eleven to twelve twice, then heat-treat at 1550℃ in a vacuum environment for 2 hours to obtain a C / SiC-ZrB2-Diamond-C porous preform.

[0078] Step fourteen: The C / SiC-ZrB2-Diamond-C porous preform obtained in step thirteen is coated with silicon powder, then wrapped with graphite paper. The C / SiC-ZrB2-Diamond-C porous preform is then placed in a silicon infiltration furnace and subjected to liquid silicon infiltration reaction at 1500℃ under vacuum for 120 minutes to obtain a high thermal conductivity C / SiC-ZrB2-Diamond composite material, the microstructure of which is shown below. Figure 5 As shown in the figure. The flexural strength of the high thermal conductivity C / SiC-ZrB2-Diamond composite material was measured, and the results are as follows. Figure 2 As shown, the flexural strength of the high thermal conductivity C / SiC-ZrB2-Diamond composite material of the present invention reaches 257 MPa.

[0079] Example 2

[0080] This invention provides a high thermal conductivity C f The preparation method of the / SiC-ZrB2-Diamond composite material specifically includes the following steps:

[0081] Step 1: A 400nm thick pyrolytic carbon layer is deposited on the fine-knitted piercing preform using the CVI process. Then, a SiC layer is deposited on the pyrolytic carbon layer using the CVI process to obtain a semi-dense porous C… f / SiC preform. In this embodiment, the thickness of the SiC layer is 3-4 μm.

[0082] Step two: Weigh the phenolic resin powder and its solvent according to the specified ratio to prepare a 10% (w / w) phenolic resin solution. Add 2% (w / w) ZrB2 particles with a particle size of 0.1 μm to the prepared phenolic resin solution and ball mill for 12-15 hours to obtain the first slurry. In this embodiment, the solvent for the phenolic resin powder is ethanol.

[0083] Step 3: Place the semi-dense porous C obtained in Step 1 into a pressure impregnation tank. f The SiC preform is suspended above the first slurry and a vacuum is applied. The preform is then immersed in the first slurry for impregnation, maintaining the vacuum condition for 1 hour. Subsequently, it is pressurized and held at 0.5 MPa for 1 hour before being removed. In this embodiment, nitrogen is used for pressurization; in other embodiments of the invention, argon or air may also be used.

[0084] Step four: The impregnated preform is cured at 150°C for 2 hours, and then subjected to pyrolysis treatment at 900°C in a vacuum environment for 3 hours to obtain the corresponding preform.

[0085] Step 5: Weigh the phenolic resin powder and its solvent according to the formula, and prepare a phenolic resin solution with a mass fraction of 20%. Add ZrB2 particles with a particle size of 5μm and diamond particles with a particle size of 6μm to the prepared phenolic resin solution, stir for 1 hour, and then sonicate for 1.5 hours. Repeat the stirring and sonication once to obtain the second slurry. The volume ratio of ZrB2 particles to diamond particles is 1:1, and the total volume of ZrB2 particles and diamond particles accounts for 6 vol.% of the total volume of the second slurry.

[0086] Step Six: Place the second slurry in a beaker, then place the beaker in a pressure impregnation tank. Suspend the preform obtained in Step Four above the second slurry. Seal the pressure impregnation tank and evacuate it. Immerse the preform in the second slurry and maintain the vacuum condition for 0.8 hours. Then, remove the preform, including the beaker, and place it in an ultrasonic disperser for ultrasonic impregnation and stirring for 10 minutes. Transfer the preform, including the beaker, to the pressure impregnation tank, seal it, and pressurize it. Hold the pressure at 1.4 MPa for 0.7 hours, then remove it.

[0087] Step 7: The preform treated in step 6 is cured at 100°C for 6 hours, and then subjected to pyrolysis treatment at 1200°C in a vacuum environment for 1 hour, thereby achieving the filling of the pores with a diffusely distributed ultra-high temperature ceramic and diamond matrix.

[0088] Step 8: Add 5 vol.% of 3 μm diamond particles to liquid polycarbosilane (LPCS), stir and disperse to obtain the third slurry. Suspend the preform treated in step 7 above the third slurry in a pressure impregnation tank and evacuate. Then immerse the preform in the third slurry and maintain the vacuum condition for 1 hour. Subsequently, pressurize and maintain the pressure at 0.5 MPa for 1 hour before taking it out.

[0089] Step nine: Place the preform treated in step eight in a vacuum environment, control the temperature at 120°C, and cure for 6 hours. Then, keep it at 1200°C in a vacuum environment for 1 hour for pyrolysis treatment to convert the precursor into a silicon carbide protective layer containing diamond particles.

[0090] Step 10: Weigh the phenolic resin powder and its solvent according to the ratio, prepare a phenolic resin solution with a mass fraction of 40%, weigh nickel chloride at a mass fraction of 3% of the phenolic resin powder and add it to the prepared phenolic resin solution. After ultrasonic dispersion for 50 minutes, continue stirring for 6 hours until the metal salt is completely dissolved to obtain the fourth slurry.

[0091] Step 11: In the pressure impregnation tank, the preform treated in step 9 is suspended above the fourth slurry and a vacuum is drawn. Then the preform is immersed in the fourth slurry and the vacuum condition is maintained for 1 hour. After that, it is pressurized and pressure is maintained at 1.4 MPa for 0.5 hours before being taken out.

[0092] Step 12: The preform treated in step 11 is cured at 150°C for 6 hours, and then subjected to pyrolysis treatment at 1200°C in a vacuum environment for 1 hour.

[0093] Step thirteen: Repeat steps eleven to twelve once, then heat-treat at 1500℃ in a vacuum environment for 1 hour to obtain a C / SiC-ZrB2-Diamond-C porous preform.

[0094] Step fourteen: Wrap the C / SiC-ZrB2-Diamond-C porous preform obtained in step thirteen with silicon powder, then wrap it with graphite paper. After that, place the C / SiC-ZrB2-Diamond-C porous preform into a silicon infiltration furnace and carry out a liquid silicon infiltration reaction at 1550℃ in a vacuum environment for 90 minutes to obtain a C / SiC-ZrB2-Diamond composite material with high thermal conductivity, thus completing the preparation.

[0095] Example 3

[0096] This invention provides a high thermal conductivity C f The preparation method of the / SiC-ZrB2-Diamond composite material specifically includes the following steps:

[0097] Step 1: A 600 nm thick pyrolytic carbon layer is deposited on the fine-knitted piercing preform using the CVI process. Then, a SiC layer is deposited on the pyrolytic carbon layer using the CVI process to obtain a semi-dense porous C… f / SiC preform. In this embodiment, the thickness of the SiC layer is 1-2 μm.

[0098] Step two: Weigh the phenolic resin powder and its solvent according to the specified ratio to prepare a phenolic resin solution with a mass fraction of 20%. Add ZrB2 particles with a particle size of 1 μm and a mass fraction of 15% to the prepared phenolic resin solution, and ball mill for 12 hours to obtain the first slurry. In this embodiment, the solvent for the phenolic resin powder is acetone.

[0099] Step 3: Place the semi-dense porous C obtained in Step 1 into a pressure impregnation tank. f The SiC preform is suspended above the first slurry and a vacuum is drawn. Then the preform is immersed in the first slurry for impregnation. The vacuum condition is maintained for 0.75 hours. Then, argon gas is introduced and pressurized. The pressure is maintained at 1.4 MPa for 0.5 hours before it is taken out.

[0100] Step four: The impregnated preform is cured at 100°C for 6 hours, and then subjected to pyrolysis treatment at 1200°C for 1 hour in a vacuum environment to obtain the corresponding preform.

[0101] Step 5: Weigh the phenolic resin powder and its solvent according to the formula, and prepare a phenolic resin solution with a mass fraction of 30%. Add ZrB2 particles with a particle size of 2μm and diamond particles with a particle size of 3μm to the prepared phenolic resin solution, stir for 1.5 hours, and then sonicate for 1 hour. Repeat the stirring and sonication treatment once to obtain the second slurry. The volume ratio of ZrB2 particles to diamond particles is 1:1, and the total volume of ZrB2 particles and diamond particles accounts for 12 vol.% of the total volume of the second slurry.

[0102] Step Six: Place the second slurry in a beaker, then place the beaker in a pressure impregnation tank. Suspend the preform obtained in Step Four above the second slurry. Seal the pressure impregnation tank and create a vacuum. Immerse the preform in the second slurry and maintain the vacuum condition for 1 hour. Then, remove the preform, including the beaker, and place it in an ultrasonic disperser for ultrasonic impregnation and stirring for 30 minutes. Transfer the preform, including the beaker, to the pressure impregnation tank, seal it, and pressurize it. Hold the pressure at 0.5 MPa for 1 hour, then remove it.

[0103] Step 7: The preform treated in step 6 is cured at 120°C for 2 hours, and then subjected to pyrolysis treatment at 900°C in a vacuum environment for 3 hours, thereby achieving the filling of the pores with dispersed ultra-high temperature ceramic and diamond matrix.

[0104] Step 8: Add 2 vol.% of 5 μm diamond particles to liquid polycarbosilane (LPCS), stir and disperse to obtain the third slurry. Suspend the preform treated in step 7 above the third slurry in a pressure impregnation tank and evacuate. Then immerse the preform in the third slurry and maintain the vacuum condition for 0.5 hours. Subsequently, pressurize and maintain the pressure at 1.4 MPa for 0.5 hours before taking it out.

[0105] Step nine: Place the preform treated in step eight in a vacuum environment, control the temperature at 180°C, and cure for 2 hours. Then, keep it at 900°C in a vacuum environment for 3 hours for pyrolysis treatment to convert the precursor into a silicon carbide protective layer containing diamond particles.

[0106] Step 10: Weigh the phenolic resin powder and its solvent according to the ratio, prepare a phenolic resin solution with a mass fraction of 20%, weigh copper nitrate (5% of the mass of the phenolic resin powder) and add it to the prepared phenolic resin solution. After ultrasonic dispersion for 10 minutes, continue stirring for 2 hours until the metal salt is completely dissolved to obtain the fourth slurry.

[0107] Step 11: In the pressure impregnation tank, suspend the preform treated in step 9 above the fourth slurry and draw a vacuum. Then, immerse the preform in the fourth slurry and maintain the vacuum condition for 0.5 hours. After that, pressurize and maintain the pressure at 0.5 MPa for 1 hour before taking it out.

[0108] Step 12: The preform treated in Step 11 is cured at 100°C for 2 hours, and then subjected to pyrolysis treatment at 900°C in a vacuum environment for 3 hours.

[0109] Step thirteen: Repeat steps eleven to twelve three times, then heat-treat at 1600℃ in a vacuum environment for 3 hours to obtain a C / SiC-ZrB2-Diamond-C porous preform.

[0110] Step fourteen: Wrap the C / SiC-ZrB2-Diamond-C porous preform obtained in step thirteen with silicon powder, then wrap it with graphite paper. After that, place the C / SiC-ZrB2-Diamond-C porous preform into a silicon infiltration furnace and carry out a liquid silicon infiltration reaction at 1600℃ in a vacuum environment for 30 minutes to obtain a C / SiC-ZrB2-Diamond composite material with high thermal conductivity, thus completing the preparation.

Claims

1. A high thermal conductive C f / SiC-ZrB2-Diamond composite material preparation method, characterized in that, Comprising the following steps: S1, sequentially depositing pyrolytic carbon layer and SiC layer on the prepared preform to obtain semi-dense porous C f / SiC preform; S2, adding ZrB2 particles or SiC particles in the phenolic resin solution, ball milling to obtain a first slurry; S3, using the first slurry to obtain semi-dense porous C f The SiC preform is sequentially subjected to vacuum pressure impregnation, curing and pyrolysis treatment. S4, using the second slurry, the preform treated by step S3 is sequentially subjected to ultrasonic impregnation, curing and pyrolysis treatment to obtain a preform filled with ultra-high temperature ceramics and diamond matrix; the second slurry is obtained by adding ZrB2 particles and diamond particles in the phenolic resin solution and mixing uniformly; S5, preparing a silicon carbide protective layer containing diamond particles inside the preform filled with ultra-high temperature ceramics and diamond matrix; specifically: S5.1, adding 2-5 vol.% of 3-5 μm diamond particles in liquid polycarbosilane, stirring and dispersing to obtain a third slurry, immersing the preform obtained by step S4 into the third slurry under vacuum condition, maintaining vacuum condition for 0.5-1 hour, then pressurizing, taking out after maintaining pressure at 0.5 MPa-1.4 MPa for 0.5-1 hour; S5.2, curing the preform treated by step S5.1 in vacuum environment at a temperature of 120-180℃ for 2-6 hours, then performing pyrolysis treatment at 900-1200℃ in vacuum environment for 1-3 hours; S6, immersing the preform treated by step S5 into a phenolic resin solution modified by a metal salt, then taking it out, carbonizing to obtain a C / SiC-ZrB2-Diamond-C porous preform; the metal salt is a nickel-containing metal salt or a copper-containing metal salt; S7, liquid silicon infiltration reaction is carried out on the C / SiC-ZrB2-Diamond-C porous preform obtained in step S6 to obtain high-thermal-conductivity C f / SiC-ZrB2-Diamond composite material, and the preparation is completed.

2. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that, Step S6 specifically comprises: S6.1, preparing a phenolic resin solution with a mass fraction of 20%-50% by using phenolic resin powder and its solvent, adding a metal salt with a mass of 1%-5% of the mass of the phenolic resin powder, stirring until the metal salt is completely dissolved to obtain a fourth slurry; the solvent is ethanol or acetone; the metal salt is nickel chloride, copper chloride, nickel nitrate or copper nitrate; S6.2, immersing the preform treated by step S5 into the fourth slurry under vacuum condition, maintaining vacuum condition for 0.5-1 hour, then pressurizing, taking out after maintaining pressure at 0.5 MPa-1.4 MPa for 0.5-1 hour; S6.3, curing the preform treated by step S6.2 at 100-150℃ for 2-6 hours, then performing pyrolysis treatment at 900-1200℃ in vacuum environment for 1-3 hours; S6.4, repeating steps S6.2 to S6.3 for 1-3 cycles, then heat treating the preform at 1500-1600℃ in vacuum environment for 1-3 hours to obtain a C / SiC-ZrB2-Diamond-C porous preform.

3. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that, Step S7 specifically comprises: Wrapping the C / SiC-ZrB2-Diamond-C porous preform obtained by step S6 with silicon powder, then wrapping it with graphite paper, then placing the C / SiC-ZrB2-Diamond-C porous preform into a silicon infiltration furnace, performing liquid silicon infiltration reaction at 1500-1600℃ in vacuum environment for 30-120 min to obtain a high-thermal-conductivity C / SiC-ZrB2-Diamond composite material, completing the preparation.

4. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that, Step S3 specifically comprises: S3.1, under vacuum, the semi-dense porous C f / SiC preform is immersed into the first slurry for impregnation, vacuum is maintained for 0.5-1 hour, then pressure is applied, and the preform is taken out after pressure is maintained at 0.5 MPa-1.4 MPa for 0.5-1 hour; S3.2, curing the impregnated preform at 100-150℃ for 2-6 hours, and then performing pyrolysis treatment at 900-1200℃ for 1-3 hours in a vacuum environment.

5. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that, Step S4 is specifically: S4.1, immersing the preform treated in step S3.2 into a second slurry under vacuum for 0.5-1 hour, placing the preform and the second slurry together in an ultrasonic disperser for ultrasonic impregnation and stirring for 10-30 minutes, and then transferring the preform and the second slurry together into a pressure impregnation tank, sealing and pressurizing, and taking out after pressure maintaining at 0.5-1.4 MPa for 0.5-1 hour; The second slurry is obtained by adding ZrB2 particles and diamond particles into a phenolic resin solution and uniformly mixing; S4.2, curing the preform treated in S4.1 at 100-150℃ for 2-6 hours, and then performing pyrolysis treatment at 900-1200℃ for 1-3 hours in a vacuum environment to obtain a preform filled with ultra-high temperature ceramic and diamond matrix.

6. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that, In step S4, the preparation method of the second slurry is specifically: According to the proportion, phenolic resin powder and its solvent are weighed respectively to prepare a phenolic resin solution with a mass fraction of 15%-30%, the solvent being ethanol or acetone, ZrB2 particles with a particle size of 2-5 μm and diamond particles with a particle size of 3-6 μm are added into the phenolic resin solution, stirring for 1-1.5 hours, and then ultrasonic treatment for 1-1.5 hours, and repeating the stirring and ultrasonic treatment to obtain the second slurry, wherein the volume ratio of ZrB2 particles to diamond particles is 1:1, and the total volume of ZrB2 particles and diamond particles accounts for 6-12 vol.% of the total volume of the second slurry; In step S1, the thickness of the pyrolytic carbon layer is 300-600 nm, and the thickness of the SiC layer is 1-4 μm; In step S2, the particle size of ZrB2 or SiC is 0.1-1 μm, and the mass of ZrB2 or SiC accounts for 2%-15% of the mass of the phenolic resin solution; the mass fraction of the phenolic resin solution is 10%-20%, and the solvent is ethanol or acetone.

7. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that: In step S1, the thickness of the pyrolytic carbon layer is 500 nm, and the thickness of the SiC layer is 2-3 μm; In step S2, the mass fraction of the phenolic resin solution is 15%, and ZrB2 particles are added into the phenolic resin solution, the particle size of the ZrB2 particles being 0.5 μm, and the mass of the ZrB2 particles accounting for 5% of the mass of the phenolic resin solution; In step S3.1, the vacuum condition is maintained for 0.5 hour, and then pressurized, and taken out after pressure maintaining at 0.8 MPa for 0.7 hour; In step S3.2, the impregnated preform is cured at 120℃ for 4 hours, and then pyrolysis treatment is performed at 1000℃ for 2 hours in a vacuum environment; In step S4.1, the preform treated in step S3.2 is immersed into a second slurry for 0.5 hour, the preform and the second slurry are placed together in an ultrasonic disperser for ultrasonic impregnation and stirring for 20 minutes, and then the preform and the second slurry are transferred together into a pressure impregnation tank, sealed and pressurized, and taken out after pressure maintaining at 0.9 MPa for 0.5 hour; In step S4.2, the preform treated in S4.1 was cured at 120℃ for 4 hours, and then pyrolysis treatment was performed at 1100℃ for 2 hours under vacuum.

8. The high thermal conductivity C f A method for preparing a / SiC-ZrB2-diamond composite material, characterized in that: In step S5.1, 4 vol.% of 4 μm diamond particles were added into the liquid polycarbosilane; the preform obtained in step S4 was immersed into the third slurry, and vacuum was maintained for 0.6 hours, followed by pressurization, and the preform was taken out after being kept at 0.8 MPa for 0.6 hours; In step S5.2, curing was performed at 150℃ for 3 hours, and then pyrolysis treatment was performed at 1000℃ for 2 hours under vacuum; In step S6.1, the mass fraction of the phenolic resin solution was 30%, and the metal salt was nickel nitrate, and the mass of the nickel nitrate was 2% of the mass of the phenolic resin powder; In step S6.2, vacuum was maintained for 0.6 hours, followed by pressurization, and the preform was kept at 0.8 MPa for 0.7 hours; In step S6.3, the preform treated in step S6.2 was cured at 120℃ for 3 hours, and then pyrolysis treatment was performed at 1000℃ for 2 hours under vacuum; In step S6.4, steps S6.2 to S6.3 were repeated for 2 cycles, and then the preform was heat treated at 1550℃ for 2 hours under vacuum; In step S7, liquid silicon infiltration reaction was performed at 1500℃ under vacuum for 120 min.

9. A high thermal conductivity C f / SiC-ZrB2-Diamond composite material prepared by the method of claim 1-8. f / SiC-ZrB2-Diamond composite material.

Images