High-conductivity ablation-resistant graphene copper-tungsten compact composite material as well as preparation method and application thereof
By preparing tungsten oxide precursors, graphene/tungsten oxide core-shell precursors, and copper plating layers, combined with discharge plasma sintering and hot processing, in-situ reaction bonding of graphene, copper, and tungsten was achieved. This solved the problems of uniform dispersion and interfacial bonding of graphene in copper-tungsten alloys, and improved the conductivity and ablation resistance of the materials.
Patent Information
- Application Number
- CN202511773896.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-28
- Publication Date
- 2026-02-17
AI Technical Summary
Existing technologies make it difficult to uniformly disperse graphene into a copper-tungsten alloy matrix to form strong interfacial bonds, leading to a decrease in the conductivity of the copper-tungsten alloy and material failure under extreme arc ablation environments.
By preparing tungsten oxide precursor, graphene/tungsten oxide core-shell precursor and copper plating layer, combined with discharge plasma sintering and thermal processing, in-situ reaction bonding of graphene, copper and tungsten is achieved, harmful interfacial reactions are suppressed, and high-density graphene-copper-tungsten composite material is obtained.
This improved the conductivity and ablation resistance of the material, resulting in a highly dense, highly conductive, and ablation-resistant graphene copper-tungsten alloy, thus overcoming the shortcomings of existing technologies in preparing high-performance graphene copper-tungsten alloys.
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Figure CN121538490A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of alloy materials technology, and in particular relates to a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, its preparation method and application. Background Technology
[0002] Copper-tungsten alloys are widely used in high-voltage electrical switches, electrical contacts, and electrode materials because they combine the good electrical and thermal conductivity of copper with the high melting point, high hardness, and resistance to arc erosion of tungsten. CuW70 and CuW80, which are copper-tungsten alloys with 70% and 80% tungsten content, are the most commonly used grades in industry.
[0003] Currently, the mainstream process for preparing copper-tungsten alloys is through powder metallurgy. The preparation process includes: mechanically mixing tungsten powder and copper powder, pressing and molding, pre-sintering, infiltration, and machining to obtain the finished copper-tungsten alloy. However, in the prepared copper-tungsten alloy, on the one hand, because the conductivity of tungsten is much lower than that of copper, the overall conductivity of the copper-tungsten alloy material will decrease significantly with the increase of tungsten content, affecting its application in high-efficiency power equipment. On the other hand, under extreme arc ablation environments, the copper phase is prone to melting and splashing, leading to the exposure and collapse of the tungsten skeleton, causing the copper-tungsten alloy material to fail. Therefore, it is necessary to perform functional modification on the copper-tungsten alloy.
[0004] Graphene possesses extremely high electrical and thermal conductivity and extremely high mechanical strength, making it an ideal reinforcing phase. However, introducing graphene into copper-tungsten systems presents significant challenges. This is because graphene has poor wettability with copper and tungsten, resulting in weak interfacial bonding. Graphene tends to agglomerate in the matrix, failing to exert its reinforcing effect and instead becoming a source of defects. Traditional powder metallurgy mixing processes struggle to achieve uniform and directional distribution of graphene between the copper and tungsten phases. Therefore, how to uniformly disperse graphene into the copper-tungsten alloy matrix, forming a strong interfacial bond with the matrix to prepare a high-density graphene-copper-tungsten alloy, and simultaneously improve the material's electrical conductivity and ablation resistance to obtain a high-performance graphene-copper-tungsten alloy, has become an urgent problem to be solved in this field. Summary of the Invention
[0005] In view of this, this application provides a highly conductive and ablation-resistant graphene copper-tungsten dense composite material, its preparation method, and its application, to solve the technical problem of difficulty in preparing high-performance graphene copper-tungsten alloys in the prior art.
[0006] The first aspect of this application provides a method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, comprising the following steps:
[0007] Preparation steps of tungsten oxide precursor: Tungsten powder and nitric acid solution are mixed and subjected to hydrothermal reaction to obtain tungsten oxide precursor powder with surface-grown tungsten oxide nanostructures;
[0008] Preparation steps of graphene / tungsten oxide core-shell precursor: Tungsten oxide precursor powder is dispersed in a carbon source solution and subjected to hydrothermal reaction followed by reduction to obtain graphene-coated graphene / tungsten oxide core-shell precursor powder, wherein the carbon source solution is at least one of glucose solution, sucrose solution, and graphene oxide solution.
[0009] Preparation steps of graphene copper-tungsten alloy composite powder: Add graphene / tungsten oxide core-shell precursor powder to copper plating solution for plating to obtain graphene copper-tungsten alloy composite powder with copper layer deposited on the surface.
[0010] The steps of discharge plasma sintering and hot processing are as follows: graphene copper-tungsten alloy composite powder is subjected to discharge plasma sintering and hot processing in sequence to obtain a dense graphene copper-tungsten composite material with high conductivity and erosion resistance.
[0011] Preferably, in the preparation step of the tungsten oxide precursor, the hydrothermal reaction temperature is 150~200℃ and the time is 6~12h.
[0012] Preferably, in the preparation step of the graphene / tungsten oxide core-shell precursor, the hydrothermal reaction temperature is 160~200℃ and the time is 6~10h.
[0013] Preferably, in the preparation step of the graphene / tungsten oxide core-shell precursor, the reduction reaction is carried out at a temperature of 500~700℃ for 1~3h, and the atmosphere is hydrogen or an argon-hydrogen mixture.
[0014] Preferably, in the preparation step of graphene copper-tungsten alloy composite powder, the plating temperature is 40~60℃ and the time is 20~40min.
[0015] Preferably, in the steps of discharge plasma sintering and thermal processing, the discharge plasma sintering temperature is 900~1050℃, the pressure is 30~50MPa, and the time is 5~15min.
[0016] Preferably, in the steps of discharge plasma sintering and hot processing, the hot processing includes at least one of hot extrusion, hot rolling or forging.
[0017] Preferably, in the steps of discharge plasma sintering and thermal processing, the mold used for discharge plasma sintering is a graphite mold with a diameter of 50 mm;
[0018] The hot extrusion temperature is 700~900℃, and the deformation time is 50~60min.
[0019] The second aspect of this application provides a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, which is prepared by the preparation method described in the first aspect.
[0020] Preferably, the highly conductive and ablation-resistant graphene-copper-tungsten dense composite material comprises, by weight, 50-80 parts of tungsten, 15-49.5 parts of copper, and 0.5-5 parts of graphene.
[0021] The third aspect of this application provides the application of the highly conductive and ablation-resistant graphene-copper-tungsten dense composite material described in the first aspect in the field of high-voltage electrical switches, electrical contacts, or electrode materials.
[0022] Compared with the prior art, the method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material provided in this application has at least the following beneficial effects:
[0023] 1. In the preparation method of a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material provided in this application, graphene, copper and tungsten are combined through in-situ reaction. The interfacial bonding between graphene, copper and tungsten is strong, and graphene is not easy to agglomerate in the matrix, so that graphene can effectively play its role as a reinforcing phase.
[0024] 2. In the preparation method of a highly conductive and ablation-resistant graphene copper-tungsten dense composite material provided in this application, the harmful interfacial reaction between graphene and copper and tungsten matrices is suppressed by the rapid sintering characteristics of spark plasma sintering, and a nearly fully dense graphene copper-tungsten composite material ingot is obtained. The internal residual pores are further eliminated by hot extrusion and other hot processing processes. Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0026] Figure 1 This is a schematic flowchart illustrating a method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, as provided in Example 1 of this application. Detailed Implementation
[0027] This application provides a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, its preparation method, and its application, which solves the technical problem of difficulty in preparing high-performance graphene-copper-tungsten alloys in the prior art.
[0028] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0029] Given the limitations of current manufacturing processes, which make it difficult to uniformly disperse graphene into a copper-tungsten alloy matrix to form a strong interfacial bond and achieve high density, high conductivity, and ablation resistance in graphene-copper-tungsten alloys, this application provides a method for preparing a highly conductive and ablation-resistant dense graphene-copper-tungsten composite material. The method includes: first, mixing tungsten powder and nitric acid and then performing a hydrothermal reaction to obtain tungsten oxide precursor powder with a surface-grown tungsten oxide nanostructure; then, dispersing the tungsten oxide precursor powder in a carbon source solution and performing a hydrothermal reaction followed by reduction to obtain a graphene / tungsten oxide core-shell precursor powder coated with graphene; subsequently, adding the graphene / tungsten oxide core-shell precursor powder to a copper plating solution for plating to obtain a graphene-copper-tungsten alloy composite powder with a deposited copper layer on the surface; finally, performing discharge plasma sintering and thermal processing to obtain a highly conductive and ablation-resistant dense graphene-copper-tungsten composite material.
[0030] In the preparation method of a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material provided in this application, a hydrothermal reaction is carried out with tungsten powder and nitric acid as an oxidant, which can generate a layer of nano-needle-shaped or sheet-like tungsten trioxide in situ on the surface of the tungsten powder. Subsequently, tungsten oxide precursor powder with surface-grown tungsten oxide nanostructures is dispersed into carbon source solutions such as glucose solution, sucrose solution, and graphene oxide solution for hydrothermal reaction. During the hydrothermal reaction, glucose can be carbonized and graphitized in situ on the surface of the tungsten oxide nanostructures. After the hydrothermal reaction, a reduction treatment is performed to obtain graphene / tungsten oxide core-shell precursor powder with in-situ graphene coating. Next, the graphene / tungsten oxide core-shell precursor powder with in-situ graphene coating is dispersed in a commercial chemical copper plating solution for plating. The commercial chemical copper plating solution contains copper ions, reducing agents, complexing agents, and functional additives, and is a chemical deposition system that does not require an external power source. The graphene / tungsten oxide core-shell precursor powder can undergo spontaneous redox reactions on the surface of the graphene / tungsten oxide core-shell precursor powder. A uniform and dense copper layer is deposited to obtain a graphene-copper-tungsten alloy composite powder with an in-situ copper layer. Finally, the graphene-copper-tungsten alloy composite powder with the in-situ copper layer is further processed. Unlike traditional mechanical powder mixing processes, the graphene-copper-tungsten alloy composite powder prepared by the method provided in this application combines graphene, copper, and tungsten through in-situ reaction. The interfacial bonding between graphene, copper, and tungsten is strong, and graphene is less prone to agglomeration in the matrix, effectively enhancing its reinforcing properties and synergistically improving conductivity and ablation resistance. Furthermore, in the subsequent preparation process, spark plasma sintering is employed. The rapid sintering characteristics of spark plasma sintering suppress harmful interfacial reactions between graphene and the copper and tungsten matrix, resulting in a nearly fully dense graphene-copper-tungsten composite ingot. Residual internal porosity is further eliminated through hot extrusion and other thermal processing techniques, yielding a highly dense, highly conductive, and ablation-resistant graphene-copper-tungsten alloy, thus overcoming the current difficulty in preparing high-performance graphene-copper-tungsten alloys.
[0031] The preparation method of a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material provided in this application will be described in detail below with reference to embodiments and experimental examples.
[0032] Example 1
[0033] This embodiment provides a method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, the process flow diagram of which is shown below. Figure 1 As shown, the process includes the preparation steps of tungsten oxide precursor, graphene / tungsten oxide core-shell precursor, graphene copper-tungsten alloy composite powder, and discharge plasma sintering and thermal processing.
[0034] The preparation steps of tungsten oxide precursor include:
[0035] Take 1 kg of tungsten powder with an average particle size of 5 μm, mix it with an appropriate amount of nitric acid, and perform a hydrothermal reaction at 180℃ for 10 hours to obtain a surface with nano-sized particles. Needle-shaped tungsten oxide precursor powder.
[0036] The preparation steps of the graphene / tungsten oxide core-shell precursor include:
[0037] Tungsten oxide precursor powder was dispersed in 20 L of 0.5 mol / L carbon source solution, transferred to a high-pressure reactor, and hydrothermally reacted at 180 °C for 8 hours. After reaction, the mixture was filtered and dried, and then reduced at 600 °C for 2 hours under H2 atmosphere to obtain graphene / tungsten oxide core-shell precursor powder coated with graphene.
[0038] The preparation steps of graphene-copper-tungsten alloy composite powder include:
[0039] Graphene-coated graphene / tungsten oxide core-shell precursor powder was added to a commercial electroless copper plating solution and plated at 50°C for 30 minutes. After filtration, washing, and drying, graphene-copper-tungsten alloy composite powder was obtained. The graphene-copper-tungsten alloy composite powder contained approximately 1.5% graphene, approximately 70% tungsten, and approximately 28.5% copper by mass.
[0040] The steps of discharge plasma sintering and thermal processing include:
[0041] Graphene copper-tungsten alloy composite powder was loaded into a Φ50mm graphite mold and sintered in a vacuum environment in an SPS sintering furnace (discharge plasma sintering) at a temperature of 980℃, a pressure of 40MPa, a holding time of 10 minutes, and a heating rate of 100℃ / min. The sintered ingot obtained by discharge plasma sintering was then hot-extruded at 800℃ with a deformation of 60% to obtain a rod-shaped, highly conductive, ablation-resistant, dense graphene copper-tungsten composite material.
[0042] Comparative Example 1
[0043] This comparative example provides a method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, including the steps of preparing copper-tungsten alloy composite powder and the steps of discharge plasma sintering and thermal processing.
[0044] The preparation steps of copper-tungsten alloy composite powder include:
[0045] Tungsten powder and copper powder with an average particle size of 5 μm were mechanically ball-milled and mixed evenly at a mass ratio of 7:3 to obtain copper-tungsten alloy composite powder.
[0046] The steps of discharge plasma sintering and thermal processing include:
[0047] The copper-tungsten alloy composite powder was loaded into a Φ50mm graphite mold and sintered in a vacuum environment in an SPS sintering furnace (discharge plasma sintering) at a temperature of 980℃, a pressure of 40MPa, a holding time of 10 minutes, and a heating rate of 100℃ / min. The sintered ingot obtained by discharge plasma sintering was hot extruded at 800℃ with a deformation of 60% to obtain rod-shaped copper-tungsten alloy composite material.
[0048] Experimental Example 1
[0049] This experiment tested the density, conductivity, and arc ablation rate of the high conductivity and ablation-resistant graphene copper-tungsten dense composite material provided in Example 1 and the copper-tungsten alloy composite material provided in Comparative Example 1. The test results are shown in Table 1.
[0050] Table 1: Test results of density, conductivity and arc ablation rate
[0051]
[0052] As shown in Table 1, the performance test results indicate that the high-conductivity, ablation-resistant graphene-copper-tungsten dense composite material provided in Example 1 has a higher density than the copper-tungsten alloy composite material provided in Comparative Example 1. According to the density calculation formula (density = actual density / theoretical density), it can be seen that the copper-tungsten alloy composite material provided in Comparative Example 1 has a higher internal porosity, while the high-conductivity, ablation-resistant graphene-copper-tungsten dense composite material provided in Example 1 has a lower internal porosity. Furthermore, compared to the copper-tungsten alloy composite material provided in Comparative Example 1, the high-conductivity, ablation-resistant graphene-copper-tungsten dense composite material provided in Example 1 has a conductivity of 52% IACS, indicating better conductivity, and a lower arc ablation rate of 0.08 mm. 3 / C, the volume loss of the material under unit arc charge is smaller, and the arc erosion resistance is better; this indicates that the graphene copper-tungsten alloy composite powder provided in this application combines graphene, copper and tungsten through in-situ reaction, with strong interfacial bonding between graphene, copper and tungsten, and graphene is not easy to agglomerate in the matrix, which can effectively play its role as a reinforcing phase. Combined with subsequent hot processing processes such as spark plasma sintering and hot extrusion, a high-density, high-conductivity and ablation-resistant graphene copper-tungsten alloy is obtained. It is a high-performance graphene copper-tungsten alloy material, which solves the technical problem of difficulty in preparing high-performance graphene copper-tungsten alloys in the prior art.
[0053] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, characterized in that, Includes the following steps: Preparation steps of tungsten oxide precursor: Tungsten powder and nitric acid solution are mixed and subjected to hydrothermal reaction to obtain tungsten oxide precursor powder with surface-grown tungsten oxide nanostructures; Preparation steps of graphene / tungsten oxide core-shell precursor: Tungsten oxide precursor powder is dispersed in a carbon source solution and subjected to hydrothermal reaction followed by reduction to obtain graphene-coated graphene / tungsten oxide core-shell precursor powder, wherein the carbon source solution is at least one of glucose solution, sucrose solution, and graphene oxide solution. Preparation steps of graphene copper-tungsten alloy composite powder: Add graphene / tungsten oxide core-shell precursor powder to copper plating solution for plating to obtain graphene copper-tungsten alloy composite powder with copper layer deposited on the surface. The steps of discharge plasma sintering and hot processing are as follows: graphene copper-tungsten alloy composite powder is subjected to discharge plasma sintering and hot processing in sequence to obtain a dense graphene copper-tungsten composite material with high conductivity and erosion resistance.
2. The method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 1, characterized in that, In the preparation step of the tungsten oxide precursor, the hydrothermal reaction temperature is 150~200℃ and the time is 6~12h.
3. The method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 1, characterized in that, In the preparation steps of the graphene / tungsten oxide core-shell precursor, the hydrothermal reaction temperature is 160~200℃ and the time is 6~10h.
4. The method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 1, characterized in that, In the preparation steps of the graphene / tungsten oxide core-shell precursor, the reduction reaction is carried out at a temperature of 500~700℃ for 1~3h, and the atmosphere is hydrogen or an argon-hydrogen mixture.
5. The method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 1, characterized in that, In the preparation steps of graphene copper-tungsten alloy composite powder, the plating temperature is 40~60℃ and the time is 20~40min.
6. The method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 1, characterized in that, In the steps of discharge plasma sintering and thermal processing, the discharge plasma sintering temperature is 900~1050℃, the pressure is 30~50MPa, and the time is 5~15min.
7. The method for preparing a highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 1, characterized in that, In the steps of discharge plasma sintering and hot processing, the hot processing includes at least one of hot extrusion, hot rolling or forging.
8. A highly conductive and ablation-resistant graphene-copper-tungsten dense composite material, characterized in that, It is prepared by the preparation method according to any one of claims 1-7.
9. The highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to claim 8, characterized in that, The highly conductive and ablation-resistant graphene-copper-tungsten dense composite material comprises, by mass, 50-80 parts of tungsten, 15-49.5 parts of copper, and 0.5-5 parts of graphene.
10. The application of the highly conductive and ablation-resistant graphene-copper-tungsten dense composite material according to any one of claims 1-7 in the field of high-voltage electrical switches, electrical contacts or electrode materials.