High-conductivity copper-based graphene composite material, preparation method and cable

Abstract

The invention belongs to the technical field of conductive materials, and particularly relates to a high-conductivity copper-based graphene composite material, a preparation method and a cable. The preparation method provided by the invention comprises the following steps: preparing layered carbon material powder such as copper powder, graphite and graphene into a block, covering the surface with a pure copper block, then melting, cooling and forming to obtain a copper / layered carbon composite material, and then carrying out equal-diameter continuous extrusion on the copper / layered carbon composite material by using a continuous extruder to obtain the copper / layered carbon composite material. Under the shear deformation effect in the plastic deformation process of equal-diameter continuous extrusion, graphite is stripped and layered to form graphene, the graphene is evenly dispersed in a copper matrix, the high-conductivity copper-based graphene composite material is obtained, the conductivity can reach 104.37%-109.68% IACS, and the conductivity can reach 104.37%-109.68% IACS. Therefore, the technical problem that a preparation method of the high-conductivity copper-based graphene composite material is lacked in the prior art is solved.

Description

Technical Field

[0001] The present application belongs to the technical field of conductive materials, and in particular relates to a highly conductive copper-based graphene composite material, a preparation method and a cable. Background Art

[0002] Copper metal has become a widely used conductor material in power transmission cables, military and industrial equipment, and electronic information fields due to its high electrical conductivity and low price. Graphene (Gr) is a kind of carbon atom in the form of sp 2 The hybrid orbitals form a two-dimensional planar film with a hexagonal honeycomb lattice and have excellent mechanical, thermal and electrical transmission properties. Introducing graphene-enhanced phases into metallic copper to construct copper-based graphene composites is one of the effective ways to overcome the physical bottleneck of the electrical conductivity of metallic copper and obtain materials with higher electrical conductivity.

[0003] Copper-based graphene composites can be prepared on a large scale using the traditional alloy melting and casting method. However, compared with metallic copper, graphene has a lower density, which results in the graphene easily floating on the surface of the copper melt during the mixed melting of metallic copper and graphene, making it difficult for graphene powder to be doped into the copper melt. At the same time, graphene itself is also easy to agglomerate, which makes the graphene dispersion in the copper melt poor, making it difficult for the copper-based graphene composites prepared by the traditional melting and casting method to exert the properties of graphene, and the electrical conductivity and other properties of the copper-based graphene composites are poor; a layer of graphene is deposited on the surface of metallic copper by chemical vapor deposition, and after repeated multiple times, the graphene can be better dispersed in the metallic copper, but this type of method requires expensive instruments and complex operating steps, and is only suitable for small-scale preparation in the laboratory, and is not suitable for large-scale preparation of copper-based graphene composites in industry; therefore, it is necessary to further improve the current traditional melting and casting method to prepare high-conductivity copper-based graphene composites. Summary of the invention

[0004] In view of this, the present application provides a high-conductivity copper-based graphene composite material, a preparation method and a power cable, which are used to solve the technical problem of the lack of a preparation method for a high-conductivity copper-based graphene composite material in the prior art.

[0005] The first aspect of the present application provides a method for preparing a highly conductive copper-based graphene composite material, the preparation method comprising:

[0006] Step S1, preparing a copper / layered carbon composite block from copper powder and layered carbon material powder;

[0007] Step S2, after placing the copper / carbon-based composite block into a crucible, covering the surface of the copper / layered carbon layer composite block with a copper block;

[0008] Step S3, placing the crucible in a vacuum melting furnace for vacuum melting to obtain a copper / carbon layered composite melt;

[0009] Step S4, cooling the copper / layered carbon composite melt to obtain a copper / layered carbon composite material;

[0010] Step S5: using a continuous extruder to perform constant-diameter continuous extrusion on the copper / layered carbon composite material to obtain a highly conductive copper-based graphene composite material.

[0011] Preferably, in step S1, the layered carbon material powder is selected from graphene and / or graphite.

[0012] Preferably, the graphene is selected from single-layer graphene, few-layer graphene or multi-layer graphene.

[0013] Preferably, the graphite is selected from flake graphite, expanded graphite or artificial graphite.

[0014] Preferably, in step S1, the particle size of the layered carbon material powder is 10-200 μm.

[0015] Preferably, in step S1, the process for making the copper / layered carbon composite block is to use a powder sintering molding process to make the copper / layered carbon composite block or a powder compression molding process to make the copper / layered carbon composite block.

[0016] Preferably, in step S2, the mass ratio of the copper / carbon-based composite block to the copper block is 1:5; in the copper / carbon-based composite block, the mass ratio of copper powder to layered carbon material powder is 95~99.99:0.01~5.

[0017] Preferably, in step S2, the crucible is selected from a graphite crucible or a ceramic crucible.

[0018] Preferably, in step S3, the vacuum degree of the vacuum melting is not greater than 20 Pa, and the melting temperature is 1100-1300°C.

[0019] Preferably, in step S4, the cooling molding process is a cooling molding process using a crystallizer, and the mold of the crystallizer is a rod-shaped mold with a diameter of 5 to 20 mm.

[0020] Preferably, in step S5, the equal-diameter continuous extrusion is 1 to 20 passes of equal-diameter continuous extrusion.

[0021] Preferably, after step S5, the method further comprises the following steps:

[0022] Step S6: Using a drawing machine to draw and deform the high-conductivity copper-based graphene composite material, and annealing to obtain a high-conductivity copper-based graphene composite wire.

[0023] Preferably, the drawing deformation is 2 to 20 passes, and the deformation amount of a single pass is 5% to 20%;

[0024] The annealing temperature is 250-450° C. and the annealing time is 1-4 hours.

[0025] Preferably, the diameter of the highly conductive copper-based graphene composite wire is 1-5 mm.

[0026] The second aspect of the present application provides a highly conductive copper-based graphene composite material prepared by the preparation method described in the first aspect.

[0027] A third aspect of the present application provides a power cable, comprising a conductor and a coating layer;

[0028] The coating layer covers the conductor;

[0029] The conductor is selected from the high-conductivity copper-based graphene composite material described in the second aspect.

[0030] In summary, the present application provides a highly conductive copper-based graphene composite material, a preparation method and a power cable. The present application provides a method for preparing a highly conductive copper-based graphene composite material, comprising making a copper / layered carbon composite block from copper powder and layered carbon material powder; placing the copper / carbon-based composite block into a crucible, and then covering the surface of the copper / layered carbon composite block with a copper block; then placing the crucible into a vacuum melting furnace for vacuum melting to obtain a copper / carbon layered composite melt; then cooling the copper / layered carbon composite melt to obtain a copper / layered carbon composite material; and using a continuous extruder to perform equal-diameter continuous extrusion on the copper / layered carbon composite material, under the action of shear deformation in the plastic deformation process of equal-diameter continuous extrusion, the graphite is peeled off and layered to form graphene, and the graphene is evenly dispersed in the copper matrix to obtain a highly conductive copper-based graphene composite material; thereby solving the technical problem of the lack of a preparation method for a highly conductive copper-based graphene composite material in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 A schematic diagram of the preparation process of a highly conductive copper-based graphene composite material provided in this application. DETAILED DESCRIPTION

[0033] The present application provides a high-conductivity copper-based graphene composite material, a preparation method and a power cable, which are used to solve the technical problem of the lack of a preparation method for a high-conductivity copper-based graphene composite material in the prior art.

[0034] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0035] In view of the fact that the copper-based graphene composite materials currently prepared by the alloy melting and casting method have the defects of poor performance such as electrical conductivity; the present application improves the existing alloy melting and casting method and provides a method for preparing a high-conductivity copper-based graphene composite material, the preparation method comprising: first using a forming process such as sintering molding or compression molding to form a copper / layered carbon composite block with copper powder and layered carbon material powder; then placing the copper / layered carbon composite block in a crucible and placing a pure copper block on its surface, and then placing the crucible in a vacuum melting furnace for vacuum melting to obtain a copper / carbon layered composite melt, and the melt is cooled and formed by flowing into a crystallizer to obtain a copper / layered carbon composite material; then using a continuous extruder to perform equal-diameter continuous extrusion on the copper / layered carbon composite material to obtain a high-conductivity copper-based graphene composite material.

[0036] In a preparation method of a high-conductivity copper-based graphene composite material provided by the present application, in the raw material preparation stage, copper powder, graphene and other layered carbon material powders are first sintered or molded into a copper / layered carbon composite block as a raw material and put into a smelting crucible, and the pure copper block raw material is covered on the copper / layered carbon composite block and then smelted, which can reduce the floating defects of graphene and other layered carbon materials during the smelting process, reduce the distribution of graphene and other layered carbon materials on the surface of the copper melt, promote the doping of graphene and other layered carbon materials into the copper melt, and improve the uniform distribution of graphene and other layered carbon materials in the copper; after the copper block and the copper / layered carbon composite block are completely melted, the copper / layered carbon composite melt flows into a crystallizer through a runner, and the crystallizer is used to cool the copper / layered carbon composite melt into a copper / layered carbon composite material, and then a continuous extruder is used to extrude the copper / layered carbon composite material in a continuous extruder, and in the plastic deformation process of the continuous extrusion, the copper / layered carbon composite material is made to be uniformly deformed. The layered carbon in the carbon composite material is peeled and delaminated under the action of shear deformation, the graphite is peeled and delaminated to form graphene, and the graphene is evenly dispersed in the copper matrix, the agglomeration of graphene is reduced, and a copper-based graphene composite material is obtained; in the preparation method of the copper-based graphene composite material provided in the present application, by covering the pure copper block raw material on the copper / layered carbon composite block and then performing smelting, equal-diameter continuous extrusion and other process settings, the graphene can be promoted to be evenly dispersed in the copper matrix, so that the graphene performance in the copper-based graphene composite material can effectively exert its electrical transmission characteristics, and the electrical conductivity of the copper matrix is ​​improved. The electrical conductivity can reach 104.37~109.68%IACS, which exceeds the international annealed copper of 58.0MS / m (100%IACS), which shows that the copper-based graphene composite material provided in the present application has high electrical conductivity, which overcomes the defects of the currently prepared copper-based graphene composite material, such as poor performance such as electrical conductivity.

[0037] Preferably, in the preparation method of the highly conductive copper-based graphene composite material provided in the present application, the particle size of the raw material layered carbon material powder used is a powder of 10~200μm; and the type of layered carbon material powder can be graphene such as single-layer graphene, few-layer graphene or multi-layer graphene, or graphite such as flake graphite, expanded graphite or artificial graphite, or a mixture of graphene and graphite; although graphene has better conductivity than graphite, it is relatively expensive. Considering the cost, graphite should be used, and considering the performance, graphene should be used.

[0038] Preferably, in the preparation method of the high-conductivity copper-based graphene composite material provided in the present application, the mass ratio of the raw material layered carbon material powder and copper powder used is 0.01~5:95~99.99, that is, for every 1kg of copper / layered carbon composite block, 0.1~50g of layered carbon materials such as graphene are used, and 950~999.9g of copper powder is used; and the mass of the copper block covering the surface of the copper / layered carbon composite block should not be lower than that of the copper / layered carbon composite block, and the mass ratio of the copper / carbon-based composite block to the copper block is 1:2, that is, for every 1kg of copper / layered carbon composite block, 1~5kg of copper block should be used.

[0039] Preferably, in the preparation method of the high-conductivity copper-based graphene composite material provided in the present application, after the copper / carbon-based composite block and the copper block are melted in a vacuum melting furnace and cooled in a crystallizer to form a rod-shaped copper / layered carbon composite material with a diameter of 5 to 20 mm, the high-conductivity copper-based graphene composite material can be prepared by equal-diameter continuous extrusion; in the equal-diameter continuous extrusion stage, the number of equal-diameter continuous extrusion passes is 2 to 20 passes; since performing multiple equal-diameter continuous extrusion passes will increase the complexity of the process and increase the production cost, the number of equal-diameter continuous extrusion passes should be controlled from the cost aspect, but the plastic deformation process of equal-diameter continuous extrusion is conducive to the peeling and stratification of layered carbon such as graphite and graphene under the action of shear deformation, which is conducive to improving the performance of the copper-based graphene composite material. Therefore, from the performance aspect, multiple equal-diameter continuous extrusion passes should be performed.

[0040] Preferably, in the preparation method of the high-conductivity copper-based graphene composite material provided in the present application, after the high-conductivity copper-based graphene composite material can be prepared by equal-diameter continuous extrusion, it also includes the steps of using a drawing machine to perform drawing deformation and annealing; a high-conductivity copper-based graphene composite wire with a diameter of 1~5mm can be obtained by drawing deformation and annealing; the high-conductivity copper-based graphene composite wire has a small diameter, which can meet the size requirements of most cables for conductors and improve the performance of the cable.

[0041] The present application also provides a cable, which includes a conductor and a coating layer; the coating layer is a conventional structure, including an insulating layer, a protective layer and other structures, and the conductor uses the high-conductivity copper-based graphene composite wire provided by the present application, which can effectively improve the performance of the cable.

[0042] The cable provided in the present application can be a cable for power transmission or a cable for signal transmission.

[0043] The preparation method of the highly conductive copper-based graphene composite material provided by the present application will be specifically described below in combination with embodiments and experimental examples.

[0044] Example 1

[0045] Example 1 of the present application provides a method for preparing a highly conductive copper-based graphene composite material, the preparation method comprising: a smelting preparation step, a vacuum melting molding step, an equal-diameter continuous extrusion step, and a wire preparation step.

[0046] Among them, the steps of smelting preparation include: preparing 5kg of pure copper block, 4.95kg of pure copper powder and 0.05kg of graphene powder (particle size 25~45μm) according to the mass of 10kg of high-conductivity copper-based graphene composite material; then sintering 4.95kg of pure copper powder and 0.05kg of graphene powder into a copper / layered carbon composite block, putting 5kg of copper / layered carbon composite block into a smelting crucible, and covering 5kg of pure copper block on the copper / layered carbon composite block to complete the smelting preparation.

[0047] The steps of vacuum melting and forming include: placing a crucible containing a copper block and a copper / layered carbon composite block in a furnace body, moving the stopper rod downward to block the flow channel to prevent the molten metal liquid copper / layered carbon composite melt from flowing into the flow channel, then closing the furnace cover to evacuate to 5 Pa, controlling the melting temperature to 1200°C to completely melt the copper block and the copper / layered carbon composite block in the crucible to form a molten metal copper / layered carbon composite melt, and then opening the flow channel. The molten metal copper / layered carbon composite melt flows into the flow channel into the crystallizer under the action of gravity, and is cooled and formed into a rod-shaped copper / layered carbon composite material with a diameter of 10 mm.

[0048] The steps of equal-diameter continuous extrusion include: after setting the continuous extrusion outlet die to 10mm, the copper / layered carbon composite material prepared by vacuum melting and molding is put into the continuous extruder as a raw material, and 5 equal-diameter continuous extrusions are performed for plastic deformation, and under the action of shear deformation, the graphene is promoted to be uniformly dispersed in the copper matrix to obtain a highly conductive copper-based graphene composite material.

[0049] The steps of preparing the wire include: drawing and deforming the high-conductivity copper-based graphene composite material after continuous extrusion, with a single-pass drawing deformation of about 10%, and after drawing to 4 mm, annealing at a temperature of 350° C. for 1 hour to obtain a linear high-conductivity copper-based graphene composite material.

[0050] Example 2

[0051] Example 2 of the present application provides a method for preparing a highly conductive copper-based graphene composite material, the preparation method comprising: a smelting preparation step, a vacuum melting and forming step, a constant-diameter continuous extrusion step, and a wire preparation step.

[0052] Among them, the steps of smelting preparation include: according to the mass of 10kg of high-conductivity copper-based graphene composite material, prepare 5kg pure copper block, 4.9kg pure copper powder and 0.1kg graphene powder (particle size 100~150μm); after sintering 4.9kg pure copper powder and 0.1kg graphene powder into a copper / layered carbon composite block, put 5Kg of copper / layered carbon composite block into a smelting crucible, and cover the 5Kg pure copper block on the copper / layered carbon composite block to complete the smelting preparation.

[0053] The steps of vacuum melting and forming include: placing a crucible containing a copper block and a copper / layered carbon composite block in a furnace body, moving the stopper rod downward to block the flow channel to prevent the molten metal liquid copper / layered carbon composite melt from flowing into the flow channel, then closing the furnace cover to evacuate to 10Pa, controlling the melting temperature to 1150°C to completely melt the copper block and the copper / layered carbon composite block in the crucible to form a molten metal copper / layered carbon composite melt, then opening the flow channel, and the molten metal copper / layered carbon composite melt flows into the flow channel into the crystallizer under the action of gravity, and is cooled and formed into a rod-shaped copper / layered carbon composite material with a diameter of 8mm.

[0054] The steps of equal-diameter continuous extrusion include: after setting the continuous extrusion outlet die to 8mm, the copper / layered carbon composite material prepared by vacuum melting and molding is put into the continuous extruder as a raw material, and three equal-diameter continuous extrusions are performed for plastic deformation, and under the action of shear deformation, the graphene is promoted to be uniformly dispersed in the copper matrix to obtain a highly conductive copper-based graphene composite material.

[0055] The steps of preparing the wire include: drawing and deforming the high-conductivity copper-based graphene composite material after continuous extrusion, with a single-pass drawing deformation of about 5%, and after drawing to 2 mm, annealing at a temperature of 450° C. for 2 hours to obtain a linear high-conductivity copper-based graphene composite material.

[0056] Example 3

[0057] Example 3 of the present application provides a method for preparing a highly conductive copper-based graphene composite material, the preparation method comprising: a smelting preparation step, a vacuum melting molding step, an equal-diameter continuous extrusion step, and a wire preparation step.

[0058] Among them, the steps of smelting preparation include: preparing 5kg of pure copper block, 4.98kg of pure copper powder and 0.02kg of graphene powder (particle size 20~50μm) according to the mass of 10kg of high-conductivity copper-based graphene composite material; then sintering 4.98kg of pure copper powder and 0.02kg of graphene powder into a copper / layered carbon composite block, putting 5Kg of copper / layered carbon composite block into a smelting crucible, and covering 5Kg of pure copper block on the copper / layered carbon composite block to complete the smelting preparation.

[0059] The steps of vacuum melting and forming include: placing a crucible containing a copper block and a copper / layered carbon composite block in a furnace body, moving the stopper rod downward to block the flow channel to prevent the molten metal liquid copper / layered carbon composite melt from flowing into the flow channel, then closing the furnace cover to evacuate to 5 Pa, controlling the melting temperature to 1200°C to completely melt the copper block and the copper / layered carbon composite block in the crucible to form a molten metal copper / layered carbon composite melt, and then opening the flow channel. The molten metal copper / layered carbon composite melt flows into the flow channel into the crystallizer under the action of gravity, and is cooled and formed into a rod-shaped copper / layered carbon composite material with a diameter of 10 mm.

[0060] The steps of equal-diameter continuous extrusion include: after setting the continuous extrusion outlet die to 10mm, the copper / layered carbon composite material prepared by vacuum melting and molding is put into the continuous extruder as a raw material, and three equal-diameter continuous extrusions are performed for plastic deformation, and under the action of shear deformation, the graphene is promoted to be uniformly dispersed in the copper matrix to obtain a highly conductive copper-based graphene composite material.

[0061] The steps of preparing the wire include: drawing and deforming the high-conductivity copper-based graphene composite material after continuous extrusion, with a single-pass drawing deformation of about 10%, and after drawing to 2 mm, annealing at a temperature of 350° C. for 1 hour to obtain a linear high-conductivity copper-based graphene composite material.

[0062] Example 4

[0063] Example 4 of the present application provides a method for preparing a copper-based graphene composite material, which is used as a comparative example of Example 1. The difference between the preparation method and Example 1 is the step of smelting preparation. The preparation method includes: a step of smelting preparation, a step of vacuum melting and molding, a step of equal-diameter continuous extrusion, and a step of wire preparation.

[0064] The steps of smelting preparation include: preparing 9.95 kg of pure copper powder and 0.05 kg of graphene powder (particle size 25-45 μm) according to the mass of 10 kg of highly conductive copper-based graphene composite materials; and then putting 9.95 kg of pure copper powder and 0.05 kg of graphene powder into a smelting crucible to complete the smelting preparation.

[0065] The steps of vacuum melting and forming include: placing a crucible containing a copper block and a copper / layered carbon composite block in a furnace body, moving the stopper rod downward to block the flow channel to prevent the molten metal liquid copper / layered carbon composite melt from flowing into the flow channel, then closing the furnace cover to evacuate to 5 Pa, controlling the melting temperature to 1200°C to completely melt the copper block and the copper / layered carbon composite block in the crucible to form a molten metal copper / layered carbon composite melt, and then opening the flow channel. The molten metal copper / layered carbon composite melt flows into the flow channel into the crystallizer under the action of gravity, and is cooled and formed into a rod-shaped copper / layered carbon composite material with a diameter of 10 mm.

[0066] The step of equal-diameter continuous extrusion includes: after setting the continuous extrusion outlet die to 10 mm, the copper / layered carbon composite material prepared by vacuum melting and molding is put into the continuous extruder as a raw material, and 5 equal-diameter continuous extrusions are performed for plastic deformation to obtain a copper-based graphene composite material.

[0067] The steps of preparing the wire include: drawing and deforming the copper-based graphene composite material, with a single-pass drawing deformation of about 10%, and after drawing to 4 mm, annealing at a temperature of 350° C. for 1 hour to obtain a linear copper-based graphene composite material.

[0068] Example 5

[0069] Example 5 of the present application provides a method for preparing a copper-based graphene composite material, which is used as a comparative example of Example 1. The difference between the preparation method and Example 1 is that the step of equal-diameter continuous extrusion is not performed; the preparation method includes: a smelting preparation step, a vacuum melting and molding step, and a wire preparation step.

[0070] Among them, the steps of smelting preparation include: preparing 5kg of pure copper block, 4.95kg of pure copper powder and 0.05kg of graphene powder (particle size 25~45μm) according to the mass of 10kg of high-conductivity copper-based graphene composite material; then sintering 4.95kg of pure copper powder and 0.05kg of graphene powder into a copper / layered carbon composite block, putting 5kg of copper / layered carbon composite block into a smelting crucible, and covering 5kg of pure copper block on the copper / layered carbon composite block to complete the smelting preparation.

[0071] The steps of vacuum melting and forming include: placing a crucible containing a copper block and a copper / layered carbon composite block in a furnace body, moving the stopper rod downward to block the flow channel to prevent the molten metal liquid copper / layered carbon composite melt from flowing into the flow channel, then closing the furnace cover to evacuate to 5 Pa, controlling the melting temperature to 1200°C to completely melt the copper block and the copper / layered carbon composite block in the crucible to form a molten metal copper / layered carbon composite melt, and then opening the flow channel. The molten metal copper / layered carbon composite melt flows into the flow channel into the crystallizer under the action of gravity, and is cooled and formed into a rod-shaped copper / layered carbon composite material with a diameter of 10 mm.

[0072] The steps of preparing the wire include: drawing and deforming the copper / layered carbon composite material with a rod-like structure, with a single-pass drawing deformation of about 10%, and after drawing to 4 mm, annealing at a temperature of 350° C. for 1 hour to obtain a linear copper-based graphene composite material.

[0073] Experimental Example 1

[0074] The present application performs performance tests on Examples 1-3 and Examples 4-5 as comparative experiments. The performance tests are conductivity tests, and the tests are performed with reference to the International Annealed Copper Standard (IACS).

[0075] The test results show that the electrical conductivity of the high conductive copper-based graphene composite material provided in Example 1 is 105.22% IACS, the electrical conductivity of the high conductive copper-based graphene composite material provided in Example 2 is 109.68% IACS, the electrical conductivity of the high conductive copper-based graphene composite material provided in Example 3 is 104.37% IACS, and the electrical conductivity of the copper-based graphene composite material provided in Examples 4-5 is lower than 100% IACS, which are 98.2% IACS and 99.1% IACS, respectively. IACS, which means that although the copper-based graphene composite materials provided in Examples 4-5 are doped with graphene in the copper matrix, the copper-based graphene composite materials provided in Example 4 do not well alleviate the defect of easy floating of graphene during the smelting process in the smelting preparation step. The copper-based graphene composite materials provided in Example 5 cannot promote the graphene to be uniformly dispersed in the copper matrix under the action of shear deformation during the plastic deformation process without continuous extrusion, so that the graphene material in the copper-based graphene composite materials cannot well exert its conductive properties, resulting in a decrease in the performance of the copper-based graphene composite materials; and the preparation methods provided in Examples 1-3, through improvements in the smelting preparation stage and the equal-diameter continuous extrusion stage, are conducive to the peeling and stratification of layered carbon such as graphite and graphene under the action of shear deformation, reduce graphene agglomeration, and promote the full performance of graphene, thereby improving the conductivity of the copper-based graphene composite materials.

[0076] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing a highly conductive copper-based graphene composite material, characterized in that: Includes steps: Step S1, preparing a copper / layered carbon composite block from copper powder and layered carbon material powder; Step S2, after placing the copper / carbon-based composite block into a crucible, covering the surface of the copper / layered carbon layer composite block with a copper block; Step S3, placing the crucible in a vacuum melting furnace for vacuum melting to obtain a copper / carbon layered composite melt; Step S4, cooling the copper / layered carbon composite melt to obtain a copper / layered carbon composite material; Step S5: using a continuous extruder to perform constant-diameter continuous extrusion on the copper / layered carbon composite material to obtain a highly conductive copper-based graphene composite material.

2. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: In step S1, the layered carbon material powder is selected from graphene and / or flake graphite.

3. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: In step S1, the particle size of the layered carbon material powder is 10-200 μm.

4. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: In step S2, the mass ratio of the copper / carbon-based composite block to the copper block is 1:5; in the copper / carbon-based composite block, the mass ratio of copper powder to layered carbon material powder is 95~99.99:0.01~5.

5. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: In step S3, the vacuum degree of the vacuum melting is not greater than 20 Pa, and the melting temperature is 1100-1300°C.

6. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: In step S4, the cooling molding process is to use a crystallizer for cooling molding, and the mold of the crystallizer is a rod-shaped mold with a diameter of 5 to 20 mm.

7. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: Step S5, the equal-diameter continuous extrusion is 2 to 20 passes of equal-diameter continuous extrusion.

8. The method for preparing a highly conductive copper-based graphene composite material according to claim 1, characterized in that: After step S5, the method further includes the following steps: Step S6: Using a drawing machine to draw and deform the high-conductivity copper-based graphene composite material, and annealing to obtain a high-conductivity copper-based graphene composite wire.

9. A highly conductive copper-based graphene composite material, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 8.

10. A cable, characterized in that: including conductor and covering; The coating layer covers the conductor; The conductor is selected from the highly conductive copper-based graphene composite material described in claim 9.

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