Preparation Method and Application of a High-Strength, High-Conductivity and Self-Lubricating Aluminum-Based Armature

Abstract

The present invention provides a preparation method and application of a high-strength and high-conductivity self-lubricating aluminum-based armature, including: dissolving a copper salt in water, mixing it with an ether compound to undergo an irreversible hydrolysis reaction, then using an alcoholamine compound as a complexing agent, obtaining a copper oxide sol after polycondensation, then dispersing a carbon group powder in the copper oxide sol, and obtaining a copper-coated carbon group powder through drying, calcination, and reduction; uniformly mixing the copper-coated carbon group powder and an aluminum alloy powder to obtain a composite powder; encapsulating the composite powder and obtaining a green compact through cold isostatic pressing; placing the green compact in a sintering furnace for sintering to obtain an aluminum-based composite material sintered ingot; forming a C-shaped or U-shaped aluminum-based composite material profile by hot extrusion processing the aluminum-based composite material sintered ingot, and then obtaining a fully dense high-strength and high-conductivity self-lubricating aluminum-based armature through machining and cutting. The method provided by the present invention has a high material utilization rate and a high manufacturing efficiency, and can realize continuous production.

Description

Technical Field

[0001] The present invention relates to the technical field of powder metallurgy aluminum-based self-lubricating materials, and particularly relates to a preparation method and application of a high-strength and high-conductivity self-lubricating aluminum-based armature. Background Art

[0002] Electromagnetic launch technology has the advantages of ultra-high initial velocity, ultra-long range, ultra-high altitude, fast response, and easy control, and has broad application prospects in the future national defense field. Taking electromagnetic rail launch as an example, at the initial stage of electromagnetic launch, a huge frictional force is formed between the armature / rail, which not only prolongs the startup time of the armature, but also limits the increase of the armature speed. Therefore, the performance of the armature directly affects the launch efficiency and stability, and also affects the service life of the launch system. As the direct carrier for driving the missile to move forward at high speed, the armature is required to have the properties of good conduction of large current, high pressure resistance, high temperature resistance, and low friction. It is usually made of lightweight aluminum alloy with relatively high conductivity and maintains good sliding contact with the rail surface.

[0003] At present, various preparation methods of armature materials have been developed at home and abroad. For example, high-strength and high-conductivity aluminum alloy armature materials are prepared by adding micro-alloyed precious metal elements (Zr, Ag, Y), or high-strength and tough heat-resistant aluminum alloy armature materials are prepared by adding rare earth elements. Although the above methods can improve the conductivity or high-temperature stability of aluminum alloy, they generally have the problems of high production cost and long manufacturing cycle. At the same time, in the existing technology during the preparation process of armature materials, the key problem of damage to the rail caused by the armature during service is rarely considered. The aluminum alloy armature not only requires excellent mechanical and electrical properties, but also excellent friction and wear properties to extend the service life of the rail.

[0004] Based on this, the present invention aims to provide a preparation method and application of a high-strength and high-conductivity self-lubricating aluminum-based armature. Summary of the Invention

[0005] The preparation method and application of the high-strength and high-conductivity self-lubricating aluminum-based armature provided by the present invention ensure that the armature has excellent friction and wear properties on the basis of high strength and high conductivity, so as to solve the technical problem in the prior art that the current-carrying friction between the armature / rail seriously damages the rail and thus affects the launch efficiency.

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] A preparation method of a high-strength and high-conductivity self-lubricating aluminum-based armature, comprising:

[0008] Step S1: Dissolve copper salt in water, mix it with an ether compound to undergo an irreversible hydrolysis reaction to form a non-ionized precursor, then use an alcoholamine compound as a complexing agent, obtain copper oxide sol after polycondensation, then disperse the carbon group powder in the copper oxide sol, and obtain copper-coated carbon group powder through drying, calcination, and reduction;

[0009] Step S2: Uniformly mix the copper-coated carbon group powder and aluminum alloy powder to obtain a composite powder;

[0010] Step S3: Package the composite powder and obtain a green compact through cold isostatic pressing;

[0011] Step S4: Place the green compact in a sintering furnace for sintering to obtain an aluminum matrix composite sintered ingot;

[0012] Step S5: Process the aluminum matrix composite sintered ingot through a hot extrusion process to form a C-shaped or U-shaped aluminum matrix composite profile, and then obtain a fully dense high-strength and high-conductivity self-lubricating aluminum matrix armature through machining and cutting.

[0013] Optionally, in step S1, the copper salt is selected from one or more of copper formate, copper acetate, copper propionate, and copper butyrate; the ether compound is selected from one or more of 2-methoxyethanol, ethylene glycol monoethyl ether, and propylene glycol monomethyl ether; the alcoholamine compound is selected from one or more of 2-aminoethanol, L-aminopropanol, and 2-aminobutanol; the carbon group powder is selected from one or more of granular graphite, flake graphite, carbon fiber, carbon nanotube, and graphene; the thickness of the copper coating layer of the carbon group powder is 5 - 100 nm.

[0014] Optionally, in step S1, the concentration of copper salt in water is 0.2 - 1 mol / L, the concentration of the ether compound in the copper salt aqueous solution is 2 - 5 mol / L, and the concentration of the alcoholamine compound in the non-ionized precursor is 2 - 5 mol / L; the particle size of the carbon group powder is 0.1 - 10 μm, and the concentration of the carbon group powder in the copper oxide sol is 0.2 - 10 g / L; the carbon group powder is ultrasonically dispersed in the copper oxide sol, and the ultrasonic time is 10 s - 10 min.

[0015] Optionally, in step S1, the drying temperature is 50 - 200 °C, and the drying time is 5 - 48 h; the calcination temperature is 200 - 900 °C, and the calcination time is 0.5 - 4 h; the reduction temperature is 350 - 800 °C, and the reduction time is 0.5 - 5 h, and the reduction atmosphere is hydrogen.

[0016] Copper-coated chalcogen powder is prepared by a sol method. To make the coating layer dense and the thickness evenly controlled within 5 - 100 nm, it is necessary to strictly control the concentrations of reactants and additives, as well as the subsequent drying, calcination, reduction temperature and time. Once the operation is improper, it is extremely easy to form free copper particles in the copper coating layer, causing the two phases of copper and chalcogen powder to separate, and unable to improve the interfacial problem between the aluminum alloy matrix and the chalcogen powder particles.

[0017] Optionally, in step S2, the content of copper-coated chalcogen powder in the composite powder is 0.1 - 5 wt%, and the balance is aluminum alloy powder. The average particle size of the aluminum alloy powder is 2 - 100 μm; one or several of V-type mixing, magnetic stirring, rolling ball milling, and vibration ball milling are used for uniform mixing of the powder.

[0018] Optionally, in step S3, cold isostatic pressing is carried out under a pressure of 50 - 400 MPa for 10 s - 10 min.

[0019] Optionally, in step S4, sintering is carried out in a vacuum or protective atmosphere. The sintering method is selected from one or several of hot press sintering, spark plasma sintering, and pressureless sintering; the sintering temperature is 400 - 650 °C, and the holding time is 5 min - 5 h; when sintering in a vacuum, the vacuum degree is 10 -1 -10 -3 Pa; when sintering in a protective atmosphere, the atmosphere is selected from nitrogen or argon, and the gas flow rate is 0.5 - 20 L / min.

[0020] To enable interdiffusion between the copper layer on the surface of the chalcogen powder particles and the aluminum matrix, the selection of the sintering process and the control of the sintering temperature and holding time are extremely important. Too high a sintering temperature or too long a holding time will cause the formation of Al4C3 compounds at the interface, reducing the conductivity. At the same time, improper control of the liquid phase quantity will also have an adverse effect on the sintering wettability; too low a sintering temperature or too short a holding time will result in insufficient densification of the sintering, with many pores, and at the same time, the diffusion of copper is also insufficient, which will seriously reduce the conductivity and increase the risk of cracking during subsequent processing.

[0021] Optionally, in step S5, the hot extrusion temperature is 250 - 500 °C, and there is also a step of preheating the hot extrusion die before hot extrusion. The preheating temperature of the hot extrusion die is 200 - 350 °C.

[0022] Directly preparing a C-shaped or U-shaped armature through a hot extrusion process can not only prepare the required shape and specifications by near-net shaping, but also further improve the strength of the armature material, significantly improve the friction and wear performance of the armature, with the mechanical properties being more than 30% higher than those of the same grade aluminum alloy and the friction coefficient being reduced by more than 50%.

[0023] Furthermore, the present invention also provides a high-strength and high-conductivity self-lubricating aluminum-based armature.

[0024] Furthermore, the present invention also provides an application of the high-strength and high-conductivity self-lubricating aluminum-based armature in electromagnetic launch.

[0025] The beneficial effects brought by the technical solution provided by the present invention at least include:

[0026] The present invention utilizes the excellent lubrication performance of the carbon group powder. Based on the principle of improving interface wetting by copper-coated carbon group powder, the carbon group powder is uniformly dispersed in the prepared copper oxide sol to achieve a layer of nano-copper oxide coated on the surface of the carbon group powder. By forming a "core-shell" composite structure of copper-coated carbon group powder, the interface wetting performance is improved. And during the high-temperature sintering process of the aluminum alloy, the copper layer on the surface of the carbon group powder particles undergoes interdiffusion with the aluminum matrix. On the one hand, it avoids the formation of Al4C3 compounds at the interface, thereby improving the conductivity. On the other hand, it improves the sintering wettability, and densification of the aluminum-based composite material is achieved through liquid-phase sintering in the later stage of sintering. The composite material prepared by the technology of the present invention has better mechanical properties, electrical conductivity and friction and wear properties than the armatures prepared by traditional casting, additive manufacturing and other processes. The aluminum-based composite material sintered ingot is formed into C-shaped or U-shaped profiles by hot extrusion process, with high material utilization rate and high manufacturing efficiency, and continuous production can be realized. The material of the present invention has important application prospects in the field of armatures for electromagnetic launch technology. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 It is a schematic process flow diagram of the present invention;

[0029] Figure 2 It is a SEM photograph of the carbon fiber / 7075 aluminum-based composite material armature in Example 1 of the present invention, where (a) is perpendicular to the extrusion direction, (b) is a partial view perpendicular to the extrusion direction, and (c) is a partial view parallel to the extrusion direction. Detailed Embodiments

[0030] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below with reference to the drawings and specific embodiments.

[0031] Example 1

[0032] 1) Weigh carbon fiber with an average particle size of 7 μm and copper acetate according to a mass ratio of 1:10. Use ultrasonic method to disperse copper acetate in deionized water with a concentration of 0.5 mol / L. Then add 760 ml of 2-methoxyethanol and use 600 mL of 2-aminoethanol as a complexing agent for magnetic stirring to obtain copper oxide sol. Finally, add carbon fiber powder and continue stirring to obtain a sol-gel system. After evaporation to dryness, a copper-coated carbon fiber xerogel precursor is obtained. Crush the precursor and calcine it in a furnace at a calcination temperature of 350 °C for 4 h to obtain copper oxide-coated carbon fiber powder.

[0033] 2) Reduce the copper oxide-coated carbon fiber powder in a hydrogen protection atmosphere at 350 °C for 5 h to obtain copper-coated carbon fiber powder.

[0034] 3) Weigh the copper-coated carbon fiber powder and 7075 aluminum alloy powder with an average particle size of 12 μm according to a mass ratio of carbon fiber to aluminum alloy powder of 8:92. Under argon protection, use a ball-to-material ratio of 5:1 and a ball milling speed of 60 r / min for 12 h to mix the copper-coated carbon fiber powder and 7075 aluminum alloy powder evenly.

[0035] 4) Compact the copper-coated carbon fiber / 7075 aluminum alloy composite powder in a silica gel envelope, seal the envelope and put it into a cold isostatic press, and keep the pressure at 150 MPa for 2 min to prepare a green sample with a diameter of 200 mm and a height of 250 mm. Put the green sample into an atmosphere sintering furnace and sinter it in an argon atmosphere with a gas flow rate of 5 L / min, a sintering temperature of 580 °C, and a sintering time of 2 h to densify and obtain an aluminum ingot.

[0036] 5) Hot extrusion forming: Heat the aluminum ingot to 350 °C, with an extrusion ratio of 20:1, and cooperate with a steel mold to hot extrude the aluminum ingot to make a C armature, and obtain a fully dense high-strength, high-conductivity and self-lubricating aluminum matrix composite armature.

[0037] After heat treatment, the room temperature tensile strength of the armature reaches 624 MPa and the conductivity is 38% IACS; using Cu-Cr-Zr copper alloy as the track material, the average friction coefficient measured in the friction and wear test with the prepared aluminum matrix armature is 0.12, and the average friction coefficient measured with traditional 7075 aluminum alloy is 0.34. The friction coefficient of the armature prepared by the present invention is reduced by 65%.

[0038] Example 2

[0039] 1) Weigh flaky graphite with an average particle size of 10 μm and copper acetate in a mass ratio of 1:10. Use ultrasonic method to disperse copper acetate in deionized water with a concentration of 0.2 mol / L. Then add 300 mL of 2-methoxyethanol and use 240 mL of 2-aminoethanol as a complexing agent for magnetic stirring to obtain copper oxide sol. Finally, add flaky graphite powder and continue stirring to obtain a sol-gel system. After evaporation to dryness, a copper-coated flaky graphite xerogel precursor is obtained. Crush the precursor and calcine it in a furnace at a calcination temperature of 400 °C for 4 h to obtain copper oxide-coated flaky graphite powder.

[0040] 2) Reduce the copper oxide-coated flaky graphite powder in a hydrogen protection atmosphere at 800 °C for 0.5 h to obtain copper-coated flaky graphite powder.

[0041] 3) Weigh the copper-coated flaky graphite powder and 2024 aluminum alloy powder with an average particle size of 25 μm according to the mass ratio of flaky graphite to aluminum alloy powder of 10:90. Under argon protection, use a V-type mixer at a rotation speed of 60 r / min for 12 h to mix the copper-coated flaky graphite powder and 2024 aluminum alloy powder evenly.

[0042] 4) Compact the copper-coated flaky graphite / 2024 aluminum alloy composite powder in a silica gel sheath. Seal the sheath and put it into a cold isostatic press, and keep the pressure at 180 MPa for 5 min to prepare a green sample with a diameter of 200 mm and a height of 250 mm. Put the green sample into a vacuum sintering furnace, evacuate to 10-3 Pa, the sintering temperature is 550 °C, and the sintering time is 2 h to densify and obtain an aluminum ingot.

[0043] 5) Hot extrusion forming: Heat the aluminum ingot to 400 °C, with an extrusion ratio of 20:1, and cooperate with a steel mold to hot extrude the aluminum ingot to make a U armature, and obtain a fully dense high-strength, high-conductivity and self-lubricating aluminum matrix composite armature.

[0044] After heat treatment, the room-temperature tensile strength of the armature reaches 508 MPa, and the conductivity is 42% IACS; using Cu-Cr-Zr copper alloy as the track material, the average friction coefficient measured in the friction and wear test with the prepared aluminum matrix armature is 0.18, and the average friction coefficient measured with the traditional 2024 aluminum alloy is 0.42. The friction coefficient of the armature prepared by the present invention is reduced by 57%.

[0045] Example 3

[0046] 1) Weigh graphene with an average particle size of 0.1 μm and copper acetate according to a mass ratio of 1:15. Disperse copper acetate in deionized water by ultrasonic method with a concentration of 0.4 mol / L, then add 600 ml of 2-methoxyethanol, use 480 ml of 2-aminoethanol as a complexing agent and stir magnetically to obtain copper oxide sol. Finally, add graphene powder and continue stirring to obtain a sol-gel system. After evaporation to dryness, a copper-coated graphene xerogel precursor is obtained. Crush the precursor and calcine it in a furnace at a calcination temperature of 400 °C for 3 h. Copper oxide-coated graphene powder is obtained.

[0047] 2) Reduce the copper oxide-coated graphene powder in a hydrogen protection atmosphere at 650 °C for 2 h to obtain copper-coated graphene powder.

[0048] 3) Weigh the copper-coated graphene powder and 7075 aluminum alloy powder with an average particle size of 20 μm according to a mass ratio of graphene to aluminum alloy powder of 0.5:99.5. Under argon protection, use the resonance mixing method and vibrate for 12 h to make the copper-coated graphene powder and 7075 aluminum alloy powder evenly mixed.

[0049] 4) Compact the copper-coated graphene / 7075 aluminum alloy composite powder in a silica gel sheath, seal the sheath and put it into a cold isostatic press, and keep the pressure at 180 MPa for 3 min to prepare a green sample with a diameter of 200 mm and a height of 250 mm. Put the green sample into an atmosphere sintering furnace and sinter it in an argon atmosphere with a gas flow rate of 0.5 L / min, a sintering temperature of 600 °C, and a sintering time of 2 h to densify and obtain an aluminum ingot.

[0050] 5) Hot extrusion forming: Heat the aluminum ingot to 370 °C, with an extrusion ratio of 16:1, and cooperate with a steel mold to hot extrude the aluminum ingot to make a C armature, and obtain a fully dense high-strength, high-conductivity and self-lubricating aluminum matrix composite armature.

[0051] After heat treatment, the room temperature tensile strength of the armature reaches 647 MPa, and the conductivity is 39% IACS; using a Cu-Cr-Zr copper alloy as the track material, the average friction coefficient measured in the friction and wear test with the prepared aluminum matrix armature is 0.1, and the average friction coefficient measured with the traditional 7075 aluminum alloy is 0.34. The friction coefficient of the armature prepared by the present invention is reduced by 70%.

[0052] Example 4

[0053] 1) Weigh carbon nanotubes with an average particle size of 2 μm and copper acetate in a mass ratio of 1:15. Use ultrasonic method to disperse copper acetate in deionized water with a concentration of 0.4 mol / L. Then add 600 mL of 2-methoxyethanol and use 480 mL of 2-aminoethanol as a complexing agent for magnetic stirring to obtain copper oxide sol. Finally, add carbon nanotubes and continue stirring to obtain a sol-gel system. After evaporation to dryness, a copper-coated carbon nanotube xerogel precursor is obtained. Crush the precursor and calcine it in a furnace at a calcination temperature of 400 °C for 3 h. Copper oxide-coated carbon nanotubes are obtained.

[0054] 2) Reduce the copper oxide-coated carbon nanotube powder in a hydrogen protection atmosphere at 500 °C for 3 h to obtain copper-coated carbon nanotube powder.

[0055] 3) Weigh the copper-coated carbon nanotube powder and 2024 aluminum alloy powder with an average particle size of 10 μm according to the mass ratio of carbon nanotubes to aluminum alloy powder of 0.5:99.5. Under argon protection, use the V-type mixing method to mix for 6 h to make the copper-coated graphene powder and 2024 aluminum alloy powder evenly mixed.

[0056] 4) Compact the copper-coated graphene / 2024 aluminum alloy composite powder in a silica gel sleeve, seal the sleeve and put it into a cold isostatic press, and keep the pressure at 180 MPa for 3 min to prepare a green sample with a diameter of 200 mm and a height of 250 mm. Put the green sample into an atmosphere sintering furnace and sinter it in a nitrogen atmosphere with a gas flow rate of 20 L / min, a sintering temperature of 600 °C, and a sintering time of 2 h to densify and obtain an aluminum ingot.

[0057] 5) Hot extrusion forming: Heat the aluminum ingot to 370 °C, with an extrusion ratio of 16:1, and cooperate with a steel mold to hot extrude the aluminum ingot to make a C armature, and obtain a fully dense high-strength, high-conductivity and self-lubricating aluminum matrix composite armature.

[0058] After heat treatment, the room temperature tensile strength of the armature reaches 512 MPa, and the conductivity is 44% IACS; using Cu-Cr-Zr copper alloy as the track material, the average friction coefficient measured in the friction and wear test with the prepared aluminum matrix armature is 0.16, and the average friction coefficient measured with traditional 2024 aluminum alloy is 0.42. The friction coefficient of the armature prepared by the present invention is reduced by 62%.

[0059] Example 5

[0060] 1) Weigh granular graphite with an average particle size of 3 μm and copper acetate in a mass ratio of 1:10. Use ultrasonic method to disperse copper acetate in deionized water with a concentration of 0.5 mol / L. Then add 800 mL of 2-methoxyethanol and use 520 mL of 2-aminoethanol as a complexing agent for magnetic stirring to obtain copper oxide sol. Finally, add granular graphite and continue stirring to obtain a sol-gel system. After evaporation to dryness, a copper-coated granular graphite xerogel precursor is obtained. Crush the precursor and calcine it in a furnace at a calcination temperature of 400 °C for 3 h. Copper oxide-coated granular graphite is obtained.

[0061] 2) Reduce the copper oxide-coated granular graphite powder in a hydrogen protection atmosphere at 450 °C for 4 h to obtain copper-coated granular graphite powder.

[0062] 3) Weigh the copper-coated granular graphite powder and 7055 aluminum alloy powder with an average particle size of 15 μm according to the mass ratio of granular graphite to aluminum alloy powder of 5:95. Under argon protection, use the V-type mixing method to mix for 6 h to make the copper-coated granular graphite powder and 7055 aluminum alloy powder evenly mixed.

[0063] 4) Compact the copper-coated granular graphite / 7055 aluminum alloy composite powder in a silica gel sheath, seal the sheath and put it into a cold isostatic press, and keep the pressure at 180 MPa for 3 min to prepare a green sample blank with a diameter of 200 mm and a height of 250 mm. Put the green sample blank into a vacuum sintering furnace, evacuate to 10-1 Pa, the sintering temperature is 620 °C, and the sintering time is 2 h to densify and obtain an aluminum ingot.

[0064] 5) Hot extrusion forming: Heat the aluminum ingot to 370 °C, with an extrusion ratio of 16:1, and cooperate with a steel mold to hot extrude the aluminum ingot to make a C armature, and obtain a fully dense high-strength, high-conductivity and self-lubricating aluminum matrix composite armature.

[0065] After heat treatment, the room temperature tensile strength of the armature reaches 706 MPa, and the conductivity is 35% IACS; using Cu-Cr-Zr copper alloy as the track material, the average friction coefficient measured in the friction and wear test with the prepared aluminum matrix armature is 0.14, and the average friction coefficient measured with the traditional 7055 aluminum alloy is 0.39. The friction coefficient of the armature prepared by the present invention is reduced by 64%.

[0066] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A preparation method of a high-strength and high-conductivity self-lubricating aluminum-based armature, characterized in that, Including: Step S1: Dissolve copper salt in water, mix it with an ether compound to cause an irreversible hydrolysis reaction to form a non-ionized precursor, then use an alcoholamine compound as a complexing agent, obtain copper oxide sol after polycondensation, then disperse carbon group powder in the copper oxide sol, and obtain copper-coated carbon group powder after drying, calcination, and reduction; Step S2: Uniformly mix the copper-coated carbon group powder and aluminum alloy powder to obtain a composite powder; Step S3: Package the composite powder and form a green body by cold isostatic pressing; Step S4: Place the green body in a sintering furnace for sintering to obtain an aluminum matrix composite sintered ingot; Step S5: Process the aluminum matrix composite sintered ingot by hot extrusion process to form a C-shaped or U-shaped aluminum matrix composite profile, and then perform machining and cutting to obtain a fully dense high-strength and high-conductivity self-lubricating aluminum matrix armature; In step S1, the copper salt is selected from one or more of copper formate, copper acetate, copper propionate, and copper butyrate; the ether compound is selected from one or more of 2-methoxyethanol, ethylene glycol monoethyl ether, and propylene glycol monomethyl ether; the alcoholamine compound is selected from one or more of 2-aminoethanol, L-aminopropanol, and 2-aminobutanol; the carbon group powder is selected from one or more of granular graphite, flake graphite, carbon fiber, carbon nanotube, and graphene; the thickness of the copper coating layer of the carbon group powder is 5-100 nm; In step S1, the concentration of copper salt in water is 0.2-1 mol / L, the concentration of the ether compound in the copper salt aqueous solution is 2-5 mol / L, and the concentration of the alcoholamine compound in the non-ionized precursor is 2-5 mol / L; the particle size of the carbon group powder is 0.1-10 μm, and the concentration of the carbon group powder in the copper oxide sol is 0.2-10 g / L; the carbon group powder is ultrasonically dispersed in the copper oxide sol, and the ultrasonic time is 10 s-10 min; In step S1, the drying temperature is 50-200 °C, and the drying time is 5-48 h; the calcination temperature is 200-900 °C, and the calcination time is 0.5-4 h; the reduction temperature is 350-800 °C, and the reduction time is 0.5-5 h, and the reduction atmosphere is hydrogen; In step S4, sintering is carried out under vacuum or a protective atmosphere, and the sintering method is selected from one or more of hot pressing sintering, spark plasma sintering, and pressureless sintering; the sintering temperature is 400-650 °C, and the holding time is 5 min-5 h; when sintering under vacuum, the vacuum degree is 10 -1 -10 -3 Pa; when sintering under a protective atmosphere, the atmosphere is selected from nitrogen or argon, and the gas flow rate is 0.5-20 L / min.

2. The method according to claim 1, characterized in that, In step S2, the content of the copper-coated carbon group powder in the composite powder is 0.1-5 wt%, and the balance is aluminum alloy powder. The average particle size of the aluminum alloy powder is 2-100 μm; one or more of V-type mixing, magnetic stirring, rolling ball milling, and vibration ball milling are used for uniform mixing of the powder.

3. The method according to claim 1, characterized in that, In step S3, cold isostatic pressing is performed under a pressure of 50-400 MPa for 10 s-10 min.

4. The method according to claim 1, characterized in that, In step S5, the hot extrusion temperature is 250-500 °C. Before hot extrusion, there is also a step of preheating the hot extrusion die, and the preheating temperature of the hot extrusion die is 200-350 °C.

5. A high-strength and high-conductivity self-lubricating aluminum-based armature prepared by the method according to any one of claims 1-4.

6. Application of the high-strength and high-conductivity self-lubricating aluminum-based armature according to claim 5 in electromagnetic launch.

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