Unidirectional continuous carbon fiber reinforced copper matrix composites with molybdenum carbide interface modification and preparation

Abstract

The application discloses a kind of molybdenum carbide interface modification unidirectional continuous carbon fiber reinforced copper-based composite material and preparation, it includes modified fiber material and copper infiltrated in modified fiber material;Modified fiber material includes unidirectional continuous arrangement mesophase pitch-based carbon fiber and Mo2C interface layer that uniform coating is covered on the surface of mesophase pitch-based carbon fiber;The application uses unidirectional continuous arrangement mesophase pitch-based carbon fiber as reinforcing body, rather than three-dimensional random orientation carbon fiber needle felt, unidirectional continuous arrangement makes all fibers parallel distribution along the same direction, forms continuous straight-through type heat conduction channel, to realize along the ultra-high directional heat conduction of fiber direction, obtains the composite material with ultra-high directional heat conduction performance, excellent dimensional stability and good mechanical property.

Description

Technical Field

[0001] This invention relates to the field of metal matrix composites, and more particularly to a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite and its preparation. Background Technology

[0002] With the continuous increase in the power density of electronic devices, higher requirements are being placed on the thermal conductivity and dimensional stability of thermal management materials. Carbon fibers (CFs), especially mesophase pitch-based carbon fibers, have extremely high axial thermal conductivity (up to 1000 W / (m·K)), making them ideal reinforcements for preparing oriented high thermal conductivity composites. Theoretically, combining them with a copper matrix, which has excellent thermal conductivity, can achieve oriented thermal conductivity exceeding that of pure copper.

[0003] However, there is a serious interfacial incompatibility problem between carbon fiber and copper: liquid copper has extremely poor wettability on carbon fiber (contact angle greater than 140°), leading to difficulty in melting and penetration, weak interfacial bonding, and the formation of numerous pores and interfacial thermal resistance, which severely restricts the improvement of the thermal conductivity of the composite material. In existing technologies, although electroless plating of copper or nickel on the surface of carbon fiber has some effect, the interfacial bonding strength and high-temperature stability between the coating and the substrate are still not ideal. Moreover, the plating process is complex and costly. The resulting composite material also suffers from isotropic or weakly anisotropic thermal conductivity, lack of directional high thermal conductivity, low thermal conductivity, and high interfacial thermal resistance.

[0004] Therefore, there is a need to provide a technical solution that can effectively improve the wettability of the carbon / copper interface, reduce the interfacial thermal resistance, and enhance the overall performance of the composite material. Summary of the Invention

[0005] In view of this, this application provides a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material and its preparation, which is used to solve the problems of interfacial porosity, large interfacial thermal resistance and mismatch of thermal expansion coefficients caused by poor interfacial wettability and poor bonding between carbon fiber and copper matrix.

[0006] To achieve the above technical objectives, this application adopts the following technical solution: In a first aspect, this application provides a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material, comprising a modified fiber material and copper infiltrated into the modified fiber material; the modified fiber material comprises unidirectionally continuously arranged mesophase pitch-based carbon fibers and a Mo2C interface layer continuously and uniformly coated on the surface of the mesophase pitch-based carbon fibers.

[0007] Preferably, its relative density is greater than or equal to 98%.

[0008] Secondly, this application provides a method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper-based composite material, comprising the following steps: S1. In a vacuum environment, mesophase pitch-based carbon fibers are impregnated in an aqueous solution of ammonium molybdate, with ammonium molybdate serving as a precursor for the Mo2C interface layer, to obtain impregnated fibers; S2. Dry the impregnated fiber and then heat it under an inert atmosphere to obtain the modified fiber material; S3. The modified fiber material is arranged in a unidirectional continuous pattern and placed in a fixture. The fixture is then placed in a graphite mold, molten pure copper liquid is introduced, and pressure melting and infiltration are performed. After cooling, the material is demolded to obtain a molybdenum carbide interface modified unidirectional continuous carbon fiber reinforced copper matrix composite material.

[0009] Preferably, in step S3, the volume fraction of the modified fiber material in the fixture is 30%–50%.

[0010] Preferably, in step S2, the heating temperature is 1100-1300℃, the heating rate is 5-15℃ / min, and the holding time is 0.5-2 h.

[0011] Preferably, in step S2, the drying temperature is 80-120℃ and the drying time is 1-3h.

[0012] Preferably, in step S1, the vacuum level of the vacuum environment is less than 100 Pa, and the immersion time is 0.5-2 h.

[0013] Preferably, in step S3, the pressure of pressure infiltration is 3-8 MPa, the infiltration temperature is 1150-1250℃, and the holding time is 0.5-2 h.

[0014] Preferably, in step S1, the concentration of the ammonium molybdate aqueous solution is 0.100~0.150 mol / L.

[0015] Thirdly, this application provides an application of molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material in the preparation of directional heat conduction components.

[0016] The beneficial effects of this application are as follows: This invention achieves metallurgical bonding between carbon fibers and a copper matrix by in-situ generating a Mo2C coating on the carbon fiber surface. Mo2C exhibits excellent wettability with liquid copper, and combined with a pressure infiltration process, molten copper can fully infiltrate and completely fill the gaps between the carbon fibers, resulting in a tight interfacial bond and effectively eliminating interfacial porosity defects. The composite material achieves a high relative density. Mo2C itself possesses excellent electrical and thermal conductivity, and as an interfacial layer, it does not significantly increase thermal resistance. The Mo2C coating acts as a "thermal bridge," reducing phonon scattering between the carbon fibers and the copper matrix, allowing for efficient heat transfer at the carbon-copper interface. This results in an axial thermal conductivity of the composite material exceeding that of pure copper. Carbon fibers have an extremely low axial coefficient of thermal expansion. The Mo2C coating enhances the interfacial bonding between the carbon fibers and the copper matrix, enabling efficient transfer of the constraint effect of the carbon fibers on the thermal expansion of the copper matrix. The composite material's axial coefficient of thermal expansion is much lower than that of pure copper, exhibiting good thermal compatibility with commonly used semiconductor materials and making it suitable for high-reliability electronic packaging. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0018] Figure 1 This is a schematic diagram of the preparation process of the molybdenum carbide interface-modified unidirectional continuous carbon fiber / copper composite material of the present invention. Figure 2 Scanning electron microscope images of the Mo2C coating on the surface of carbon fibers under different ammonium molybdate concentrations; Figure 3 Scanning electron microscope (SEM) images of carbon fibers with Mo2C coatings grown at different ammonium molybdate concentrations after copper impregnation. Detailed Implementation

[0019] The embodiments of the technical solution of this application will be described in detail below. The following embodiments are only used to illustrate the technical solution of this application more clearly, and are therefore only examples, and should not be used to limit the scope of protection of this application.

[0020] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0021] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0023] Unless otherwise explicitly defined and specified herein, all technical and scientific terms used in this application shall have the generally accepted meanings understood by one of ordinary skill in the field of chemical and chemical materials technology (including but not limited to polymer chemistry, inorganic chemistry, organic synthesis, catalysis chemistry, materials processing, and chemical unit operations) based on their professional knowledge and conventional practice. The use of any terminology herein is intended to describe the specific embodiments of this application in the clearest and most accurate manner, so as to fully disclose the technical solution. Such use shall not in any way be construed as a limitation on the scope of the claims, nor does it imply the exclusion of equivalent technical solutions that could be reasonably known by one of skill in the art based on the concept of this application.

[0024] The terms "comprising," "including," "having," "containing," and any grammatical variations or similar expressions used in the specification and claims of this application are all open-ended and non-exhaustive descriptive terms. Their purpose is to explicitly describe the existence of technical features, components, steps, or parts, while explicitly allowing and covering the possibility that other features, components, steps, parts, or any combinations thereof not explicitly listed may exist or be added to the technical solution, as long as such additions do not destroy the integrity and inventiveness of the original technical solution.

[0025] When the terms "embodiments," "some embodiments," or "specific embodiments" are mentioned in the specification, they refer to examples that, in conjunction with the specific parameters, materials, steps, and results described in that section, constitute one or a group of examples for implementing the technical solutions of this application. These embodiments are used for full disclosure and illustrative purposes, not for exhaustive enumeration. Those skilled in the art should understand that, without departing from the overall inventive concept of this application, the various technical features disclosed in different embodiments can be combined, substituted, modified, or deleted to form other implementation methods that are not listed one by one in the specification but also fall within the protection scope of this application.

[0026] Unless otherwise expressly specified and limited, all terms related to chemical process operations, material preparation, processing and analytical testing involved in this application shall be interpreted in the broadest sense based on the conventional understanding of those skilled in the art.

[0027] Regarding performance testing and structural characterization, all testing and characterization methods involved in this application, unless otherwise specified, refer to conventional methods known in the art. Specific testing conditions may be selected and adjusted according to the sample properties and relevant national standards, international standards, or industry-standard methods. Test items may include mechanical properties (such as tensile, bending, and impact strength), thermal properties (such as DSC and TGA analysis), and chemical stability (such as solvent resistance and acid / alkali corrosion resistance). Structural characterization methods may include FT-IR, NMR, XRD, SEM, TEM, and BET. All test results should be understood to be within the allowable range of conventional experimental errors.

[0028] Regarding numerical values ​​and ranges, all parameter ranges expressed in this application in the form of "from a certain value to a certain value" should be understood as explicitly disclosing the endpoints of the range, each specific numerical point between the endpoints, and all sub-ranges formed by any two numerical points within the range. For example, "30℃ to 80℃" discloses 30, 31, ..., 80℃, as well as sub-ranges such as 30-50℃, 45-70℃, etc. When a numerical value is preceded by "about," "approximately," or similar words, it indicates that the numerical value is allowed to have reasonable errors recognized in the art under the measurement or control conditions, which can generally be understood as the deviation allowed by relevant standards or a normal fluctuation range of ±5% or ±10%.

[0029] This application provides a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material, including modified fiber material and copper infiltrated into the modified fiber material; the modified fiber material includes unidirectionally continuously arranged mesophase pitch-based carbon fibers and a Mo2C interface layer continuously and uniformly coated on the surface of the mesophase pitch-based carbon fibers.

[0030] In this application, unidirectionally continuously arranged mesophase pitch-based carbon fibers are used as the reinforcement, rather than three-dimensional randomly oriented carbon fiber needle-punched felt. The unidirectional continuous arrangement ensures that all fibers are parallel to each other in the same direction, forming a continuous, straight-through thermal conductivity channel, thereby achieving ultra-high directional thermal conductivity along the fiber direction. A Mo2C coating is continuously and uniformly coated on the surface of the continuously arranged mesophase pitch-based carbon fibers. The Mo2C coating achieves metallurgical bonding between the continuously arranged mesophase pitch-based carbon fibers and the copper matrix, significantly improving the wettability of the copper melt on the carbon fibers and constructing an efficient heat / mechanical transfer channel. This results in a composite material with ultra-high directional thermal conductivity, excellent dimensional stability, and good mechanical properties. It is worth noting that the Mo2C in this application is a continuous and uniform Mo2C interface layer coated on the carbon fiber surface, rather than dispersed nanoparticles. The resulting molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material has a thermal conductivity of 320~450 W / (m·K) along the fiber axis and an axial coefficient of thermal expansion of 2.5~5.5. With a strength of ppm / K, a flexural strength along the fiber axis of 220~350 MPa, and a flexural modulus of 100~150 GPa, it solves the problems of wettability and interfacial thermal resistance at the carbon / copper interface.

[0031] In some embodiments, the relative density of the molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material is greater than or equal to 98%; the Mo2C coating coverage is not less than 70%.

[0032] This application provides a method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper-based composite material, comprising the following steps: S1. In a vacuum environment, mesophase pitch-based carbon fibers are impregnated in an aqueous solution of ammonium molybdate, with ammonium molybdate serving as a precursor for the Mo2C interface layer, to obtain impregnated fibers; S2. Dry the impregnated fiber and then heat it under an inert atmosphere to obtain the modified fiber material; S3. The modified fiber material is arranged in a unidirectional continuous pattern and placed in a fixture. The fixture is then placed in a graphite mold, molten pure copper liquid is introduced, and pressure melting and infiltration are performed. After cooling, the material is demolded to obtain a molybdenum carbide interface modified unidirectional continuous carbon fiber reinforced copper matrix composite material.

[0033] This application addresses the shortcomings of poor wettability and high interfacial thermal resistance between carbon fiber and copper. A solution impregnation-carbothermic reduction method is used to generate a continuous and dense molybdenum carbide (Mo2C) interfacial layer in situ on the surface of mesophase pitch-based carbon fibers. Then, the fiber volume fraction is controlled using a graphite plate clamp, and the carbon fiber is composited with copper through a pressure melting process. The Mo2C coating significantly improves the wettability of copper on carbon fibers. Combined with pressure melting, molten copper fully fills the fiber gaps, resulting in a tight interfacial bond. This yields a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper-based composite material. This material exhibits a low axial thermal expansion coefficient, high flexural strength, and higher axial thermal conductivity than pure copper.

[0034] Specifically, such as Figure 1 As shown, in step S1, mesophase pitch-based carbon fiber (Shaanxi Tianze New Material Technology Co., Ltd.) is cut to a set length. The axial thermal conductivity of the mesophase pitch-based carbon fiber is not less than 900 W / (m·K), and the monofilament diameter of the mesophase pitch-based carbon fiber is 8~12 μm. After drying, it is ready for use. In step S2, the pretreated carbon fibers are placed in a vacuum environment and completely immersed in ammonium molybdate (NH4)6Mo7O. 24 • The carbon fibers are impregnated in an aqueous solution of 4H₂O for 0.5–2 h to ensure that the ammonium molybdate solution is uniformly adhered to the surface of each monofilament carbon fiber. The impregnated carbon fibers are then dried to allow complete evaporation of moisture, resulting in the crystallization and uniform loading of ammonium molybdate onto the fiber surface. The dried carbon fibers are then placed in a tube furnace and heated to 1100–1300 °C under an inert atmosphere (argon or nitrogen) and held at that temperature for 0.5–2 h. This allows the ammonium molybdate to undergo thermal decomposition and a carbothermic reduction / carbonization reaction with the carbon fibers, generating a continuous and dense molybdenum carbide coating in situ on the carbon fiber surface, thus obtaining Mo₂C modified carbon fibers. The main reaction formula for the carbothermic reduction / carbonization reaction is: 2MoO₂ + 3C → Mo₂C + 2CO₂. In this step, the solution impregnation method directly loads ammonium molybdate onto the surface of each monofilament carbon fiber. Compared to the molten salt method, the direct contact between ammonium molybdate and the carbon fiber surface results in a higher efficiency carbothermic reduction reaction, and the coating thickness can be precisely controlled by the precursor concentration.

[0035] In step S3, the Mo2C modified carbon fibers are arranged in a unidirectional continuous pattern (fibers are laid out unidirectionally along the mold) and placed in a fixture. The fiber volume fraction is controlled by adjusting the fixture. The fixture containing the Mo2C modified carbon fibers is placed in a graphite mold, molten pure copper liquid is introduced, pressure is applied for pressure melting and infiltration, and the sample is demolded after cooling. The sample is removed after demolding and the excess copper on the surface is removed by machining to obtain a molybdenum carbide interface modified unidirectional continuous carbon fiber reinforced copper matrix composite material.

[0036] In some embodiments, in step S3, the volume fraction of the modified fiber material in the fixture is 30-50%.

[0037] In this embodiment, the fixture is a graphite plate fixture, and the volume fraction of modified fibers is adjusted by bolt fastening. By using a graphite plate fixture in conjunction with bolt adjustment, the volume fraction of carbon fibers can be precisely controlled. The operation is simple and has good repeatability. By adjusting the fiber content, the thermal conductivity, mechanical properties and thermal expansion properties of the composite material can be optimized.

[0038] In some embodiments, in step S2, the heating temperature is 1100-1300℃, the heating rate is 5-15℃ / min, and the holding time is 0.5-2 h.

[0039] In some embodiments, in step S2, the drying temperature is 80-120°C and the drying time is 1-3 hours.

[0040] In some embodiments, in step S1, the vacuum level of the vacuum environment is less than 100 Pa, and the immersion time is 0.5-2 h.

[0041] In some embodiments, in step S3, the pressure of pressure infiltration is 3-8 MPa, the infiltration temperature is 1150-1250℃, and the holding time is 0.5-2 h.

[0042] In some embodiments, in step S1, the concentration of the ammonium molybdate aqueous solution is 0.100~0.150 mol / L.

[0043] In this embodiment, the ammonium molybdate concentration is adjusted to control the thickness and morphology of the Mo2C coating. In addition, the control of the thickness and morphology of the Mo2C coating also includes the control of reaction temperature and reaction time.

[0044] This application provides an application of molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material in the preparation of directional heat conduction components.

[0045] The molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material of this application has a precisely controllable fiber content. The resulting composite material has ultra-high directional thermal conductivity, low thermal expansion and good mechanical properties, and is suitable for directional thermal conductivity components in high-power chip heat dissipation, electronic packaging and aerospace fields.

[0046] The following specific embodiments further illustrate this solution.

[0047] Example 1 A method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper-based composite material includes the following steps: S1. Mesophase pitch-based carbon fibers (single filament diameter of about 10 μm, axial thermal conductivity of not less than 900 W / (m·K)) are cut to a length of 8 mm and have an axial thermal conductivity of not less than 900 W / (m·K). After drying at 100℃, they are set aside for use. The pretreated carbon fibers are placed in an environment with a vacuum degree of less than 100 Pa and completely immersed in an aqueous solution of 0.125 mol / L ammonium molybdate for 1 h to obtain impregnated fiber bundles. S2. The impregnated carbon fiber is transferred to a 100℃ constant temperature drying oven and dried for 2 hours. The dried carbon fiber is placed in a tube furnace and heated to 1200℃ at a heating rate of 10℃ / min under argon protection and held for 1 hour to obtain the modified fiber material. S3. Mo2C modified carbon fibers are arranged in a unidirectional continuous pattern and placed in a graphite plate fixture. The fiber volume fraction is controlled to be 50 vol.% by adjusting the fixture bolts. The modified fiber material is placed in a graphite mold along with the fixture. The graphite mold is placed in a high-temperature vacuum furnace, and molten pure copper liquid (1200℃) is introduced. Pressure melting and infiltration are performed by applying 5MPa pressure. After holding at this temperature for 1 h, the furnace is cooled to room temperature. The sample is demolded and removed. Excess copper on the surface is removed by mechanical grinding to obtain the molybdenum carbide interface modified unidirectional continuous carbon fiber reinforced copper matrix composite material.

[0048] Example 2 A method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material is the same as that in Example 1, except that the concentration of ammonium molybdate is 0.1 mol / L.

[0049] Example 3 A method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material is the same as that in Example 1, except that the concentration of ammonium molybdate is 0.15 mol / L.

[0050] Example 4 A method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material is the same as that in Example 1, except that the carbon fiber volume fraction is 40 vol.

[0051] Example 5 A method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material is the same as that in Example 1, except that the carbon fiber volume fraction is 30 vol.

[0052] Comparative Example 1 A method for preparing a carbon fiber reinforced copper-based composite material is the same as in Example 1, except that the ammonium molybdate aqueous solution is replaced with water.

[0053] Testing and Evaluation The performance of different composite materials was tested: thermal conductivity was determined using the laser scintillation method (LFA 457), the coefficient of thermal expansion was determined using a thermomechanical analyzer (DIL 402C), and flexural strength was determined using a universal testing machine. The test results are shown in Table 1.

[0054] Table 1 Test Results

[0055] The relative density of the composite material obtained in Example 1 was 98.5%; the Mo2C coating in the composite material obtained in Example 2 was discontinuously distributed with a coating coverage of 70%; the Mo2C coating in the composite material obtained in Example 3 was continuous but showed obvious thickening characteristics, and the outline of some fiber edges was blurred, indicating that the fiber body was consumed to a certain extent during the reaction process; the molten copper in the composite material obtained in Comparative Example 1 could not effectively infiltrate the carbon fiber preform, the composite material had a large number of pores and unfilled areas, and the interface bonding was extremely poor, which could not meet the requirements of thermal management applications.

[0056] Electron microscopy was performed on the Mo2C coating on the surface of carbon fibers with different ammonium molybdate concentrations and the composite materials obtained by copper impregnation of carbon fibers with Mo2C coating grown with different ammonium molybdate concentrations. Figure 2 Scanning electron microscope (SEM) images of the Mo2C coating on the surface of carbon fibers under different ammonium molybdate concentrations are shown. Figure 2 (a1, a2) is 0.1 mol / L. Figure 2 (b1, b2) is 0.125 mol / L. Figure 2 (c1, c2) is 0.15 mol / L; where subscript 1 is an electron microscope image parallel to the fiber axis and subscript 2 is an electron microscope image perpendicular to the fiber axis. Figure 3 These are scanning electron microscope (SEM) images of carbon fibers with Mo2C coatings grown at different ammonium molybdate concentrations after copper impregnation. Figure 3 (a) is 0.1 mol / L. Figure 3 (b) 0.125 mol / L, Figure 3 (c) 0.15 mol / L; where subscript 1 is an electron microscope image parallel to the fiber axis and subscript 2 is an electron microscope image perpendicular to the fiber axis.

[0057] The above results demonstrate that, in this application, unidirectionally continuously arranged mesophase pitch-based carbon fibers are used as the reinforcement, rather than three-dimensional randomly oriented carbon fiber needled felt. The unidirectional continuous arrangement ensures that all fibers are distributed parallel in the same direction, forming a continuous, straight-through thermal conductivity channel. This achieves ultra-high directional thermal conductivity along the fiber direction. A Mo2C coating continuously and uniformly coats the surface of the continuously arranged mesophase pitch-based carbon fibers, achieving metallurgical bonding between the carbon fibers and the copper matrix through the Mo2C coating. This significantly improves the wettability of the copper melt on the carbon fibers, constructing an efficient heat / mechanical transfer channel, thereby obtaining a composite material with ultra-high directional thermal conductivity, excellent dimensional stability, and good mechanical properties. The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper-based composite material, characterized in that, The material includes a modified fiber material and copper infiltrated into the modified fiber material; the modified fiber material includes unidirectionally continuously arranged mesophase pitch-based carbon fibers and a Mo2C interface layer continuously and uniformly coated on the surface of the mesophase pitch-based carbon fibers.

2. The molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material according to claim 1, characterized in that, Its relative density is greater than or equal to 98%.

3. A method for preparing a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material as described in any one of claims 1-2, characterized in that, Includes the following steps: S1. In a vacuum environment, mesophase pitch-based carbon fibers are impregnated in an aqueous solution of ammonium molybdate, with ammonium molybdate serving as a precursor for the Mo2C interface layer, to obtain impregnated fibers; S2. The impregnated fibers are dried and then heated under an inert atmosphere to obtain the modified fiber material; S3. The modified fiber material is arranged in a unidirectional continuous pattern and placed in a fixture. The fixture is then placed in a graphite mold, molten pure copper liquid is introduced, and pressure melting and infiltration are performed. After cooling, the material is demolded to obtain the molybdenum carbide interface modified unidirectional continuous carbon fiber reinforced copper matrix composite material.

4. The preparation method according to claim 3, characterized in that, In step S3, the volume fraction of the modified fiber material in the fixture is 30%–50%.

5. The preparation method according to claim 3, characterized in that, In step S2, the heating temperature is 1100-1300℃, the heating rate is 5-15℃ / min, and the holding time is 0.5-2 h.

6. The preparation method according to claim 3, characterized in that, In step S2, the drying temperature is 80-120℃ and the drying time is 1-3 hours.

7. The preparation method according to claim 3, characterized in that, In step S1, the vacuum level of the vacuum environment is less than 100 Pa, and the immersion time is 0.5-2 h.

8. The preparation method according to claim 3, characterized in that, In step S3, the pressure of the pressure infiltration is 3-8 MPa, the infiltration temperature is 1150-1250℃, and the holding time is 0.5-2 h.

9. The preparation method according to claim 3, characterized in that, In step S1, the concentration of the ammonium molybdate aqueous solution is 0.100~0.150 mol / L.

10. The application of a molybdenum carbide interface-modified unidirectional continuous carbon fiber reinforced copper matrix composite material obtained by the preparation method according to any one of claims 3-8 in the preparation of directional heat-conducting components.

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