Ultrahigh-temperature ceramic matrix coating integrated composite material as well as preparation method and application thereof
By combining chemical liquid phase vaporization deposition with reactive melting infiltration, the density and pore distribution of porous ceramic matrix composites are controlled to form a ceramic phase, which serves as the carbon source for in-situ ceramic generation during reactive melting infiltration. This solves the problems of easy oxidation of carbon/carbon composites at high temperatures and mismatch between the ceramic coating and the matrix, and achieves efficient preparation of ultra-high temperature ceramic matrix coating integrated composites with improved ablation resistance and mechanical properties.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NORTHWESTERN POLYTECHNICAL UNIV
- Filing Date
- 2026-01-21
- Publication Date
- 2026-04-24
AI Technical Summary
Existing carbon/carbon composites are prone to oxidation at high temperatures, and the thermophysical mismatch between the ceramic coating and the matrix leads to cracking and peeling. Chemical liquid phase vaporization deposition has a fast densification rate but low ceramic introduction amount, and reactive melting infiltration method damages carbon fibers, making it difficult to achieve efficient synergy.
By combining chemical liquid phase vaporization deposition with reactive melting infiltration, the density and pore distribution of porous ceramic matrix composites are controlled through chemical liquid phase vaporization deposition to form a ceramic phase, which serves as an in-situ carbon source for ceramic generation during reactive melting infiltration, thereby synergistically improving ceramic content and oxidation resistance.
The rapid preparation of an integrated composite material with an ultra-high temperature ceramic matrix coating has been achieved, which significantly improves the ablation resistance and mechanical properties of the material, reduces damage to carbon fibers, and has good prospects for industrial application.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of carbon / carbon composite matrix modification technology, specifically relating to an integrated composite material with ultra-high temperature ceramic matrix coating, its preparation method and application. Background Technology
[0002] Carbon / carbon (C / C) composites are ideal candidates for the thermal structures of hypersonic vehicles due to their lightweight, high strength, and high-temperature resistance. However, their susceptibility to oxidation at high temperatures limits their practical application. Modifying the matrix with ultra-high-temperature ceramics or preparing coatings can significantly improve the oxidation and ablation resistance of these materials. However, matrix-modified C / C composites often suffer from limited protection due to the non-dense formation of the surface oxide layer, while the surface ceramic coating is prone to cracking and peeling in high-temperature service environments due to thermophysical mismatch between the coating and the matrix. Therefore, a composite structure design strategy that synergistically reinforces the matrix and coating has become a key technological direction for further improving the ablation resistance of C / C composites.
[0003] Chemical liquid phase vapor deposition (CLVI / CLVD), as an improved process of chemical vapor deposition (CVI / CVD), offers a densification rate more than two orders of magnitude faster than reported isothermal chemical vapor deposition, thus significantly reducing preparation costs and shortening the preparation cycle. However, when preparing ceramic matrix composites, although the co-deposition of pyrolytic carbon with the ceramic phase can alleviate the thermal expansion mismatch between components, it also results in a low ceramic content, making it difficult to form a dense oxide layer during ablation and affecting the material's ablation resistance. Therefore, achieving densification of high-ceramic-content composites solely through chemical liquid phase vapor deposition remains a challenge.
[0004] In traditional matrix modification methods, reactive infiltration (RMI) utilizes capillary forces to infiltrate a molten material into a porous preform, generating a modified ultra-high temperature ceramic phase through a chemical reaction with carbon. This process offers advantages such as high preparation efficiency, strong ceramic incorporation capability, and the ability to form coatings in situ. However, the high-temperature alloy melt inevitably damages the carbon fibers, leading to a decrease in the mechanical properties of the composite material. Therefore, reactive infiltration places stringent requirements on the density and porosity of the preform: too low a density causes premature pore sealing, hindering further penetration and resulting in numerous internal pores; too high a density limits the penetration depth due to narrow pores, significantly reducing the amount of ceramic introduced.
[0005] Therefore, how to coordinate the pore structure of the preform prepared by chemical liquid phase vaporization deposition with the penetration requirements of the reaction melting and infiltration process has become a key challenge to achieve efficient synergy between the two. Summary of the Invention
[0006] In order to overcome the shortcomings of the prior art, the present invention aims to provide an integrated composite material for ultra-high temperature ceramic matrix coating, its preparation method and application, wherein the integrated composite material for ultra-high temperature ceramic matrix coating is rapidly prepared by chemical liquid phase vaporization deposition and reactive melting infiltration method.
[0007] To achieve the above objectives, the present invention employs the following technical solution: This invention provides an integrated composite material with an ultra-high temperature ceramic matrix coating, comprising an ultra-high temperature ceramic modified composite material and a coating formed in situ on the surface of the ultra-high temperature ceramic modified composite material; the ultra-high temperature ceramic modified composite material is obtained by reactive melt infiltration of a porous ceramic matrix modified composite material and melt infiltration powder; the coating is obtained by reactive melt infiltration of melt infiltration powder that has not penetrated into the porous ceramic matrix modified composite material; the porous ceramic matrix modified composite material is obtained by chemical liquid-phase vaporization deposition of a carbon fiber preform in a mixed organic precursor solution, followed by heat treatment; In the porous ceramic-based modified composite material, the ceramic phase and pyrolytic carbon are co-deposited around the carbon fibers, and the pyrolytic carbon serves as the carbon source for in-situ ceramic generation during the reaction melting process. The ceramic phase in the ultra-high temperature ceramic modified composite material is partly derived from the ceramic phase of the porous ceramic matrix modified composite material, and the remaining part is formed by the infiltration of the infiltrated powder through the porous structure of the porous ceramic matrix modified composite material and reacting with carbon during the reaction infiltration process.
[0008] This invention also provides a method for preparing an integrated composite material with an ultra-high temperature ceramic matrix coating, comprising the following steps: S1: Dissolve the ceramic polymer precursor in an organic solvent to obtain a mixed organic precursor solution; perform chemical liquid-phase vaporization deposition of the carbon fiber preform in the mixed organic precursor solution and then cool it to obtain the deposited composite material. S2: The deposited composite material is heat-treated and then cooled to obtain a porous ceramic-based modified composite material. S3: For materials with a density of 1.0~1.6 g / cm³ 3 A porous ceramic-based modified composite material is placed in a melt-infiltrating powder to introduce a ceramic phase through reactive melt-infiltrating and form a surface coating in situ, thereby obtaining an integrated composite material with an ultra-high temperature ceramic matrix coating.
[0009] In one embodiment, in S1, the ceramic polymer precursor is any one or a mixture of polycarbosilane, hafnium carbide precursor, zirconium carbide precursor, and tantalum carbide precursor; the organic solvent is any one or a mixture of xylene, toluene, cyclohexane, and kerosene.
[0010] In one embodiment, in S1, the density of the carbon fiber preform is 0.4~1.0 g / cm³.3 The carbon fiber preform is a cylindrical carbon fiber preform with dimensions of φ80~120mm×10~30mm.
[0011] In one embodiment, in S1, the mass fraction of the ceramic polymer precursor in the mixed organic precursor solution is 5%-60%.
[0012] In one embodiment, the chemical liquid phase vaporization deposition process in S1 is as follows: The carbon fiber preform was placed in a liquid phase furnace containing a mixed organic precursor solution and heated to 800-1200°C at a rate of 10-20°C / min. Chemical liquid phase vaporization deposition was carried out for 4-16 hours, and then cooled to 600°C at a rate of 10-20°C / min.
[0013] In one embodiment, the heat treatment process in S2 is as follows: Under an argon atmosphere, the temperature is increased to 1500-1800℃ at a rate of 2-5℃ / min and held for 2-4 hours.
[0014] In one embodiment, in S3, the infiltrating powder is any one or more mixtures of zirconium disilicide, hafnium disilicide, tantalum disilicide, and copper-zirconium alloy.
[0015] In one embodiment, the reactive melting process in S3 is as follows: Under an argon atmosphere, the temperature is increased to 1700-2100℃ at a rate of 2-5℃ / min and held for 0.5-2 hours.
[0016] This invention also provides an application of an integrated composite material with an ultra-high temperature ceramic matrix coating in the field of thermal protection.
[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention provides an integrated ultra-high temperature ceramic matrix coating composite material, which is rapidly prepared using chemical liquid phase vapor deposition and reactive melting methods. The key advantage lies in the precise control of the density and pore distribution of the porous ceramic matrix modified composite material through chemical liquid phase vapor deposition, providing a transport channel for the large-scale introduction of the ceramic phase during the subsequent reactive melting process. Furthermore, addressing the problems of low ceramic introduction and insufficient oxidation and ablation resistance in existing chemical liquid phase vapor deposition processes due to the co-deposition of ceramic phase and pyrolytic carbon, this invention transforms "pyrolytic carbon co-deposition" into an advantage through a combined process. The ceramic phase formed during the chemical liquid phase vapor deposition stage can resist the erosion of the high-temperature alloy melt, while the simultaneously deposited pyrolytic carbon serves as a carbon source for in-situ ceramic formation during the subsequent reactive melting process. The synergistic effect of these two processes significantly reduces damage to carbon fibers during melting. The innovation of this invention lies in solving the challenge of preparing high-ceramic-content composite materials using chemical liquid phase vapor deposition, enabling the rapid preparation of ultra-high temperature ceramic matrix-coating integrated composite materials with both excellent mechanical properties and ablation resistance.
[0018] In particular, the reactive melting method in the combined process can be extended to a variety of modification methods such as precursor impregnation and pyrolysis, chemical vapor deposition, slurry coating and sintering, gas / liquid phase silicon infiltration, and atmospheric plasma spraying, demonstrating the high flexibility and efficiency of the process route, and showing good industrial application prospects and economic benefits. Attached Figure Description
[0019] Figure 1 This is a process flow diagram for preparing the ultra-high temperature ceramic matrix coating integrated composite material of the present invention; Figure 2 BSE diagram of porous ceramic-based modified composite materials prepared by chemical liquid phase vapor deposition process; Figure 3 (af) shows the microstructure of porous ceramic-based modified composite materials with different densities before and after reactive melting infiltration prepared in Example 1; (g) is a schematic diagram of reactive melting infiltration of porous ceramic-based modified composite materials; (h) shows porous ceramic-based modified composite materials under mercury intrusion method; (i) and (j) show the changes in density and porosity before and after reactive melting infiltration. Figure 4 XRD results for an integrated composite material with an ultra-high temperature ceramic matrix and coating; Figure 5 (a) and (b) are SEM images of the surface of the ultra-high temperature ceramic matrix coating integrated composite material; (c) is the SEM image of the cross section and related surface scan energy dispersive spectroscopy results. Figure 6(a) shows the bending stress-displacement curve of the composite material prepared by the reactive melting process in Comparative Example 1; (b) shows the bending stress-displacement curve of the composite material prepared by the chemical liquid phase vaporization deposition and reactive melting process of the present invention (Example 2). Figure 7 (a) shows the linear and mass ablation rates of the composite materials prepared by the single chemical liquid phase vaporization deposition process and the combined chemical liquid phase vaporization deposition-reactive melting infiltration process; (b) shows the macroscopic morphology of the composite materials after ablation obtained by the single chemical liquid phase vaporization deposition process and the combined chemical liquid phase vaporization deposition-reactive melting infiltration process. Detailed Implementation
[0020] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.
[0021] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.
[0022] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values (including integers and fractions) within those ranges.
[0023] In this article, unless otherwise specified, the terms “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of”. For example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a”.
[0024] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.
[0025] This invention provides an integrated ultra-high temperature ceramic matrix coating composite material, its preparation method, and its application. It employs a synergistic process system combining chemical liquid phase vapor deposition (CLPV) and reactive infiltration. CLPV precisely controls the density and pore distribution of the porous ceramic matrix modified composite material, providing optimized infiltration channels for subsequent reactive infiltration, thereby significantly increasing the ceramic content of the matrix. Simultaneously, the ceramic phase formed during CLPV resists erosion by high-temperature alloy melts, and the co-deposited pyrolytic carbon can also serve as a carbon source for in-situ ceramic formation during reactive infiltration, synergistically mitigating fiber damage. This results in a material with both excellent ablation resistance and mechanical properties. This combined process provides an ideal approach for preparing high-performance integrated ultra-high temperature ceramic matrix coating composite materials.
[0026] This invention provides an integrated ultra-high temperature ceramic matrix coating composite material, comprising an ultra-high temperature ceramic modified composite material and a coating formed in situ on the surface; the ultra-high temperature ceramic modified composite material is obtained by reactive melt infiltration of a porous ceramic matrix modified composite material and melt infiltration powder; the coating is obtained by reactive melt infiltration of melt infiltration powder that has not penetrated into the porous ceramic matrix modified composite material. Figure 2 The study revealed the structural characteristics of the co-deposition of ceramic phase and pyrolytic carbon around carbon fibers. In the porous ceramic matrix modified composite material, the ceramic phase and pyrolytic carbon are co-deposited around the carbon fibers. During the reaction melting process, the pyrolytic carbon serves as the carbon source for in-situ ceramic generation. Part of the ceramic phase in the ultra-high temperature ceramic modified composite material originates from the ceramic phase of the porous ceramic matrix modified composite material, while the remaining part is formed by the melting powder infiltrating through the porous structure of the porous ceramic matrix modified composite material and reacting with carbon during the reaction melting process.
[0027] Figure 4 The XRD results are for an integrated composite material with an ultra-high temperature ceramic matrix and coating.
[0028] Figure 5 Microscopic morphology of the ultra-high temperature ceramic matrix coating integrated composite material; Figure 5 (a) and (b) are SEM images of the surface; Figure 5 (c) shows the SEM image of the cross section and the relevant surface scan energy spectrum results.
[0029] like Figure 1 As shown, the present invention also provides a method for preparing an integrated composite material with an ultra-high temperature ceramic matrix coating, comprising the following steps: S1: Dissolve the ceramic polymer precursor in an organic solvent to obtain a mixed organic precursor solution; perform chemical liquid-phase vaporization deposition of the carbon fiber preform in the mixed organic precursor solution and then cool it to obtain the deposited composite material; in S1, the mass fraction of the ceramic polymer precursor in the mixed organic precursor solution is 5%-60%. S2: The deposited composite material is heat-treated and then cooled to obtain a porous ceramic-based modified composite material. S3: For materials with a density of 1.0~1.6 g / cm³ 3 A porous ceramic-based modified composite material is placed in a melt-infiltrating powder to introduce a ceramic phase through reactive melt-infiltrating and form a surface coating in situ, thereby obtaining an integrated composite material with an ultra-high temperature ceramic matrix coating.
[0030] In one embodiment, in step S1, the density of the carbon fiber preform is 0.4~1.0 g / cm³. 3 The carbon fiber preform is a cylindrical carbon fiber preform with dimensions of φ80~120mm×10~30mm.
[0031] In one embodiment, in step S1, the ceramic polymer precursor is any one or a mixture of multiple precursors selected from polycarbosilane, hafnium carbide, zirconium carbide, and tantalum carbide; the organic solvent is any one or a mixture of xylene, toluene, cyclohexane, and kerosene. In step S3, the infiltrating powder is any one or a mixture of zirconium disilicide, hafnium disilicide, tantalum disilicide, and copper-zirconium alloy.
[0032] In S1, the chemical liquid phase vaporization deposition process is as follows: The carbon fiber preform was placed in a liquid phase furnace containing a mixed organic precursor solution and heated to 800-1200°C at a rate of 10-20°C / min. Chemical liquid phase vaporization deposition was carried out for 4-16 hours, and then cooled to 600°C at a rate of 10-20°C / min.
[0033] In step S2, the heat treatment process is as follows: Under an argon atmosphere, the temperature is increased to 1500-1800℃ at a rate of 2-5℃ / min and held for 2-4 hours.
[0034] In step S3, the reactive melt infiltration process is as follows: Under an argon atmosphere, the temperature is increased to 1700-2100℃ at a rate of 2-5℃ / min and held for 0.5-2 hours.
[0035] This invention also provides an application of an integrated composite material with an ultra-high temperature ceramic matrix coating in the field of thermal protection.
[0036] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.
[0037] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.
[0038] Example 1: (1) The ceramic polymer precursor (polysilane and zirconium carbide precursor) was dissolved in 10L xylene at a mass fraction of 60% to obtain a mixed organic precursor solution. After ultrasonic dispersion for 2 hours, a uniform mixed organic precursor solution was obtained. (2) The density is 0.4 g / cm³ 3 A preform with dimensions of φ80mm×10mm and components such as heating elements H1 and H2 are assembled in a reaction vessel, and the mixed organic precursor solution obtained in step (1) is poured in so that the upper surface of the heating element H1 is immersed in the mixed organic precursor solution. (3) Start the equipment, adjust the power to raise the heating element H2 to 900°C at 10°C / min, keep it at 900°C for 3 hours, then lower it to 600°C at 10°C / min, and then turn off the power to cool it down with the furnace. (4) The composite material obtained in step (3) is placed in a heat treatment furnace under an argon atmosphere, heated to 1500℃ at a rate of 2℃ / min, held at that temperature for 2 hours, and then cooled with the furnace to obtain a material with a density of 0.9-1.7 g / cm³. 3 The detailed preparation process of the porous C / C-ZrC-SiC preform is shown in Table 1. (5) The preform obtained in step (4) is placed in a graphite crucible containing zirconium disilicide powder and subjected to reaction melting treatment at 1700℃ for 2 hours under argon protection to finally obtain a C / C-ZrC-SiC composite material with a ZrSi2 / ZrC / SiC coating on the surface.
[0039] By introducing a chemical liquid phase vaporization deposition process before the reactive melting process, the resulting ceramic phase can effectively resist the erosion of high-temperature alloy melts. The co-deposited pyrolytic carbon can serve as a carbon source for in-situ ceramic synthesis in subsequent melting processes. The synergistic effect of the two processes significantly reduces the damage to fibers during the melting process, thereby significantly improving the bending strength of the material.
[0040] Meanwhile, the precise control of density and pore distribution in porous ceramic-based modified composite materials through chemical liquid-phase vaporization deposition provides structural channels for the infiltration of the ceramic phase during the melting and infiltration stage, achieving a significant increase in the ceramic content of the matrix. If the density of the preform is too low, the melt is prone to prematurely blocking the pores, hindering its continued infiltration and resulting in a large number of unfilled pores remaining inside the material; if the density is too high, the small pore size will significantly limit the penetration depth of the melt, resulting in a severe deficiency in the introduction of the ceramic phase. After ablation, a continuous and dense oxide layer forms on the material surface, exhibiting excellent ablation resistance.
[0041] Table 1 Chemical liquid phase vaporization deposition process for low-density C / C-ZrC-SiC preforms
[0042] Example 2: (1) The ceramic polymer precursor (polysilane and zirconium carbide precursor) was dissolved in 10L xylene at a mass fraction of 50% to obtain a mixed organic precursor solution. After ultrasonic dispersion for 2 hours, a uniform mixed organic precursor solution was obtained. (2) The density is 0.8 g / cm³ 3 A preform with dimensions of φ80mm×10mm and components such as heating elements H1 and H2 are assembled in a reaction vessel, and the mixed organic precursor solution obtained in step (1) is poured in so that the upper surface of the heating element H1 is immersed in the mixed organic precursor solution. (3) Start the equipment, adjust the power to raise the heating element H2 to 900°C at 10°C / min, keep it at 900°C for 4 hours, then lower it to 600°C at 10°C / min, and then turn off the power to cool it down with the furnace. (4) The composite material obtained in step (3) was placed in a heat treatment furnace under an argon atmosphere, heated to 1500℃ at a rate of 2℃ / min, held at that temperature for 2 hours, and then cooled with the furnace to obtain a density of 1.4 g / cm³. 3 Porous C / C-ZrC-SiC preforms; (5) The preform obtained in step (4) is placed in a graphite crucible containing zirconium disilicide powder and subjected to reaction melting treatment at 1700℃ for 2 hours under argon protection to finally obtain a C / C-ZrC-SiC composite material with a ZrSi2 / ZrC / SiC coating on the surface.
[0043] Example 3: (1) The ceramic polymer precursor (polysilane, zirconium carbide and tantalum carbide precursor) was dissolved in 10L of toluene at a mass fraction of 30% to obtain a mixed organic precursor solution. After ultrasonic dispersion for 2 hours, a uniform mixed organic precursor solution was obtained. (2) The density is 0.6 g / cm³ 3A preform with dimensions of φ80mm×15mm and components such as heating elements H1 and H2 are assembled in a reaction vessel, and the mixed organic precursor solution obtained in step (1) is poured in so that the upper surface of the heating element H1 is immersed in the mixed organic precursor solution. (3) Start the equipment, adjust the power to raise the heating element H2 to 800°C at 15°C / min, keep it at 8h, then lower it to 600°C at 15°C / min, and then turn off the power to cool it down with the furnace. (4) The composite material obtained in step (3) was placed in a heat treatment furnace under an argon atmosphere, heated to 1600℃ at a rate of 3℃ / min, held at that temperature for 2 hours, and then cooled with the furnace to obtain a density of 1.4 g / cm³. 3 Porous C / C-ZrC-TaC-SiC preforms; (5) The preform obtained in step (4) is placed in a graphite crucible containing zirconium disilicide and tantalum disilicide powder, and subjected to reaction melting treatment at 1900℃ for 0.5h under argon protection to finally obtain a C / C-ZrC-TaC-SiC composite material with a ZrSi2-TaSi2 / ZrC-TaC / SiC coating on the surface.
[0044] Example 4: (1) The ceramic polymer precursor (polysilane and hafnium carbide precursor) was dissolved in 10L cyclohexane at a mass fraction of 10% to obtain a mixed organic precursor solution. After ultrasonic dispersion for 2h, a uniform mixed organic precursor solution was obtained. (2) The density is 0.8 g / cm³ 3 A preform with dimensions of φ100mm×20mm and components such as heating elements H1 and H2 are assembled in a reaction vessel, and the mixed organic precursor solution obtained in step (1) is poured in so that the upper surface of the heating element H1 is immersed in the mixed organic precursor solution. (3) Start the equipment, adjust the power to raise the heating element H2 to 1000℃ at 20℃ / min, keep it at 12h, then lower it to 600℃ at 20℃ / min, and then turn off the power to cool it with the furnace. (4) The composite material obtained in step (3) was placed in a heat treatment furnace under an argon atmosphere, heated to 1700℃ at a rate of 4℃ / min, held at that temperature for 2 hours, and then cooled with the furnace to obtain a density of 1.4 g / cm³. 3 Porous C / C-HfC-SiC preforms; (5) The preform obtained in step (4) is placed in a graphite crucible containing hafnium disilicide powder and subjected to reaction melting and infiltration treatment at 2100℃ for 1 hour under argon protection to finally obtain a C / C-HfC-SiC composite material with HfSi2 / HfC / SiC coating on the surface.
[0045] Example 5: (1) The ceramic polymer precursors (polysilane, hafnium carbide, zirconium carbide and tantalum carbide precursors) were dissolved in 10L of kerosene at a mass fraction of 5% to obtain a mixed organic precursor solution. After ultrasonic dispersion for 2 hours, a uniform mixed organic precursor solution was obtained. (2) The density is 1.0 g / cm³ 3 A preform with dimensions of φ120mm×30mm and components such as heating elements H1 and H2 are assembled in a reaction vessel, and the mixed organic precursor solution obtained in step (1) is poured in so that the upper surface of the heating element H1 is immersed in the mixed organic precursor solution. (3) Start the equipment, adjust the power to raise the heating element H2 to 1200℃ at 10℃ / min, keep it at 12h, then lower it to 600℃ at 10℃ / min, and then turn off the power to cool it with the furnace. (4) The composite material obtained in step (3) was placed in a heat treatment furnace under an argon atmosphere, heated to 1800℃ at a rate of 5℃ / min, held at that temperature for 2 hours, and then cooled with the furnace to obtain a density of 1.4 g / cm³. 3 Porous C / C-HfC-ZrC-TaC-SiC preforms; (5) The preform obtained in step (4) is placed in a graphite crucible containing copper-zirconium alloy and subjected to reactive melting treatment at 1200℃ for 2 hours under argon protection to finally obtain a surface with Zr x Cu y Coated C / C-HfC-ZrC-TaC-SiC-Cu composite material.
[0046] Comparative Example 1: A density of 1.4 g / cm³ was selected. 3 The C / C preform was placed in a graphite crucible containing zirconium disilicide powder and subjected to reaction melting treatment at 1700℃ for 2 hours under argon protection, finally obtaining a C / C-ZrC-SiC composite material with a ZrSi2 / ZrC / SiC coating on the surface.
[0047] The erosive effect of high-temperature alloy melt during reactive infiltration can easily damage carbon fibers, thus affecting the mechanical properties of the composite material. To address this, this invention employs a chemical liquid phase vaporization deposition process to pre-prepare porous ceramic-based modified composite materials. The deposited ceramic phase effectively resists the erosion of the high-temperature alloy melt, while the co-deposited pyrolytic carbon serves as the carbon source for in-situ ceramic formation during subsequent reactive infiltration. The synergistic effect of both significantly reduces fiber damage during the infiltration process.
[0048] Comparative analysis shows that, compared to a single reactive infiltration process, the ultra-high temperature ceramic matrix coating integrated composite material prepared by a combined chemical liquid phase vaporization deposition and reactive infiltration process (Example 2) exhibits a 105% increase in flexural strength, demonstrating superior mechanical properties (see [link to relevant documentation]). Figure 6).
[0049] Comparative Example 2: (1) The ceramic polymer precursor (polysilane and zirconium carbide precursor) was dissolved in 10L xylene at a mass fraction of 50% to obtain a mixed organic precursor solution. After ultrasonic dispersion for 2 hours, a uniform mixed organic precursor solution was obtained. (2) The density is 0.8 g / cm³ 3 A preform with dimensions of φ80mm×10mm and components such as heating elements H1 and H2 are assembled in a reaction vessel, and the mixed organic precursor solution obtained in step (1) is poured in so that the upper surface of the heating element H1 is immersed in the mixed organic precursor solution. (3) Start the equipment, adjust the power to raise the heating element H2 to 900°C at 10°C / min, keep it at 900°C for 36 hours, then lower it to 600°C at 10°C / min, and then turn off the power to cool it down with the furnace. (4) The composite material obtained in step (3) is placed in a heat treatment furnace under an argon atmosphere, heated to 1600°C at 5°C / min, kept at the temperature for 2 hours and then cooled with the furnace to obtain the C / C-ZrC-SiC composite material.
[0050] Figure 3 (af) shows the microstructure of porous ceramic-based modified composite materials with different densities prepared in Example 1 before and after reactive melting and infiltration; Figure 3 (g) is a schematic diagram of reactive melting infiltration of porous ceramic-based modified composite materials; Figure 3 (h) is a porous ceramic-based modified composite material under mercury intrusion porosimetry. It can be seen that the pore diameter of the mesh layer is about 10 μm to 100 μm, and the pore diameter of the non-woven fabric layer is about 500 nm to 3 μm, leaving channels for the subsequent infiltration of reactive ceramics. Figure 3 (i) and (j) show the changes in density and porosity before and after reactive melting and infiltration, and it can be seen that the density is less than 1.0 g / cm³. 3 At that time, the composite material after reactive melting and infiltration has high porosity and a density greater than 1.6 g / cm³. 3 At that time, the density change of the composite material after reaction melting and infiltration was small, and the amount of ceramic introduced was small.
[0051] Figure 6 (a) is the bending stress-displacement curve of the composite material prepared by the reactive melting process in Comparative Example 1; Figure 6 (b) is the bending stress-displacement curve of the composite material prepared by the chemical liquid phase vaporization deposition and reactive melting process of the present invention (Example 2). During the reactive melting process, the ceramic phase formed in the chemical liquid phase vaporization deposition stage can resist the erosion of the high-temperature alloy melt. At the same time, the co-deposited pyrolytic carbon can serve as the carbon source for in-situ ceramic generation. The two work together to significantly reduce the damage to the carbon fibers during the melting process, thereby significantly improving the bending strength of the composite material.
[0052] Figure 7 (a) The linear and mass ablation rates of composite materials prepared by a single chemical liquid phase vaporization deposition process and a combined chemical liquid phase vaporization deposition-reactive melting infiltration process were compared. The results show that the materials prepared using the combined process of this invention have significantly improved ablation resistance. Figure 7 (b) shows the macroscopic morphology of the composite materials obtained by the two processes after ablation. Due to the low ceramic content introduced by the single chemical liquid phase vaporization deposition process, the ceramic and pyrolytic carbon co-deposition process failed to form a dense oxide layer on the surface after ablation. However, the material prepared by the chemical liquid phase vaporization deposition-reactive melting infiltration combined process has a significantly increased ceramic content, and a continuous and dense oxide layer is formed on the surface after ablation, exhibiting excellent ablation resistance.
[0053] When preparing ceramic matrix composites using chemical liquid phase vapor deposition, the co-deposition of pyrolytic carbon and ceramic phase can alleviate the thermal expansion mismatch between components, but it also leads to a low ceramic incorporation amount, making it difficult to form a dense oxide layer during ablation, thus reducing the material's ablation resistance (see [link]). Figure 7 By using chemical liquid-phase vapor deposition to prepare porous ceramic-based modified composite materials, and combining it with a subsequent reactive infiltration process, the porous structure can be used to efficiently infiltrate the ceramic phase, thereby significantly increasing the ceramic content of the matrix. After ablation, a dense oxide layer forms on the material surface, reducing the mass ablation rate by 73%, exhibiting excellent ablation resistance (see [link to article]). Figure 7 ).
[0054] This invention provides an integrated ultra-high temperature ceramic matrix coating composite material, its preparation method, and its application. Addressing the problems of low ceramic introduction and insufficient oxidation and ablation resistance in existing chemical liquid phase vaporization deposition processes due to the co-deposition of ceramic phase and pyrolytic carbon, this invention transforms "pyrolytic carbon co-deposition" into a key advantage through a combined chemical liquid phase vaporization deposition and reactive melting process. The pyrolytic carbon formed in the chemical liquid phase vaporization deposition stage serves as the carbon source for in-situ ceramic generation during the subsequent reactive melting process, while the simultaneously deposited ceramic phase effectively resists the erosion of the high-temperature alloy melt, jointly reducing damage to the fibers. Simultaneously, the porous structure constructed in this stage provides transport channels for ceramic phase melting and infiltration, significantly increasing the ceramic content of the matrix and thus improving the material's oxidation and ablation resistance. Furthermore, the reactive melting step in this process can be extended to various modification methods such as precursor impregnation and pyrolysis, slurry coating and sintering, or gas / liquid phase silicate infiltration, demonstrating high flexibility and efficiency in the process path, and possessing promising industrial application prospects and economic benefits.
[0055] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of this invention.
Claims
1. A composite material with an integrated coating on an ultra-high temperature ceramic matrix, characterized in that, The invention includes an ultra-high temperature ceramic modified composite material and a coating formed in situ on the surface of the ultra-high temperature ceramic modified composite material; the ultra-high temperature ceramic modified composite material is obtained by reactive melt infiltration of a porous ceramic matrix modified composite material and melt-infiltrating powder; the coating is obtained by reactive melt infiltration of melt-infiltrating powder that has not penetrated into the porous ceramic matrix modified composite material; the porous ceramic matrix modified composite material is obtained by chemical liquid-phase vaporization deposition of carbon fiber preform in a mixed organic precursor solution, followed by heat treatment; In the porous ceramic-based modified composite material, the ceramic phase and pyrolytic carbon are co-deposited around the carbon fibers, and the pyrolytic carbon serves as the carbon source for in-situ ceramic generation during the reaction melting process. The ceramic phase in the ultra-high temperature ceramic modified composite material is partly derived from the ceramic phase of the porous ceramic matrix modified composite material, and the remaining part is formed by the infiltration of the infiltrated powder through the porous structure of the porous ceramic matrix modified composite material and reacting with carbon during the reaction infiltration process.
2. A method for preparing an integrated ultra-high temperature ceramic matrix coating composite material as described in claim 1, characterized in that, Includes the following steps: S1: Dissolve the ceramic polymer precursor in an organic solvent to obtain a mixed organic precursor solution; The carbon fiber preform was chemically vaporized and deposited in a mixed organic precursor solution and then cooled to obtain the deposited composite material. S2: The deposited composite material is heat-treated and then cooled to obtain a porous ceramic-based modified composite material. S3: For materials with a density of 1.0~1.6 g / cm³ 3 A porous ceramic-based modified composite material is placed in a melt-infiltrating powder to introduce a ceramic phase through reactive melt-infiltrating and form a surface coating in situ, thereby obtaining an integrated composite material with an ultra-high temperature ceramic matrix coating.
3. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S1, the ceramic polymer precursor is any one or a mixture of polycarbosilane, hafnium carbide precursor, zirconium carbide precursor, and tantalum carbide precursor; the organic solvent is any one or a mixture of xylene, toluene, cyclohexane, and kerosene.
4. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S1, the density of the carbon fiber preform is 0.4~1.0 g / cm³. 3 The carbon fiber preform is a cylindrical carbon fiber preform with dimensions of φ80~120mm×10~30mm.
5. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S1, the mass fraction of the ceramic polymer precursor in the mixed organic precursor solution is 5%-60%.
6. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S1, the chemical liquid phase vaporization deposition process is as follows: The carbon fiber preform was placed in a liquid phase furnace containing a mixed organic precursor solution and heated to 800-1200°C at a rate of 10-20°C / min. Chemical liquid phase vaporization deposition was carried out for 4-16 hours, and then the temperature was cooled to 600°C at a rate of 10-20°C / min.
7. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S2, the heat treatment process is as follows: Under an argon atmosphere, the temperature is increased to 1500-1800℃ at a rate of 2-5℃ / min and held for 2-4 hours.
8. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S3, the infiltrated powder is any one or more mixtures of zirconium disilicide, hafnium disilicide, tantalum disilicide, and copper-zirconium alloy.
9. The preparation method of the ultra-high temperature ceramic matrix coating integrated composite material according to claim 2, characterized in that, In S3, the reaction melting process is as follows: Under an argon atmosphere, the temperature is increased to 1700-2100℃ at a rate of 2-5℃ / min and held for 0.5-2 hours.
10. The application of an integrated composite material with an ultra-high temperature ceramic matrix coating as described in claim 1 in the field of thermal protection.