CN105603248A - Foam graphene skeleton reinforced copper-base composite material and preparation method thereof - Google Patents

Abstract

A foamed graphene skeleton reinforced copper-based composite material and a preparation method thereof, the composite material is composed of a foam substrate, a graphene reinforced layer, and a matrix material, and the foam substrate is foamed metal, foamed ceramics or foamed carbon. The graphene reinforced layer is a composite of graphene film or graphene, diamond and carbon nanotubes. The base material is copper and copper alloy. The composite material prepared by the present invention maintains a continuous distribution of graphene and aluminum in a three-dimensional space, forming a network interpenetrating structure, thereby weakening the significant impact of the composite interface on the thermal and electrical properties of the material, and not reducing the metal matrix in the composite material. The good plasticity and toughness in the material can also make the reinforced phase a whole, maximize the thermal conductivity and electrical conductivity of the reinforcement, and greatly improve the thermal conductivity, electrical conductivity and mechanical strength of the composite material compared with traditional composite materials. , is a new type of multifunctional composite material with great potential.

Description

A kind of foamed graphene skeleton reinforced copper-based composite material and preparation method thereof

technical field

The invention discloses a foamed graphene skeleton-reinforced copper-based composite material and a preparation method thereof, belonging to the technical field of composite material preparation.

Background technique

Graphene is a two-dimensional crystal that is exfoliated from graphite material and composed of carbon atoms with only one layer of atomic thickness. In 2004, Andre Geim and Konstantin Novoselov, physicists at the University of Manchester, successfully separated graphene from graphite and confirmed that it can exist alone. Bell Prize in Physics. Graphene is both the thinnest material and the strongest, with a breaking strength 200 times stronger than the best steel. At the same time, it has good elasticity, and the stretching range can reach 20% of its own size. It is currently the thinnest and strongest material in nature. If a piece of graphene with an area of 1 square meter is used to make a hammock, it can bear a cat weighing one kilogram with a weight of less than one milligram. As a new type of nanomaterial with the thinnest, highest strength, and strongest electrical and thermal conductivity found so far, graphene is called "black gold" and is the "king of new materials". Scientists even predict that graphene will "completely change the 21st century." ".

On May 8, 2014, a group of young researchers from AVIC Aerospace Materials Institute created the "graphene alloy" material for the first time in the international graphene research field. The new high-end alloy material also makes my country a leader in basic and applied research on the frontier of graphene, a material science. The successful development of ene alloys announced the emergence of a new series of materials with special and excellent properties, filling the gaps in the field of materials science in the world, and pushing this subject to a new field.

Graphene is currently the man-made material with the highest thermal conductivity (up to 5300W/mK), and its thermal expansion coefficient and density are extremely low. Graphene is used as a reinforcing phase and combined with a high thermal conductivity metal to ensure an ideal thermal expansion coefficient and low density. At the same time, more excellent thermal conductivity can be obtained. Since Cu has higher thermal conductivity and electrical conductivity than Al, and the thermal expansion coefficient is lower than Al, using Cu as the matrix metal to prepare graphene powder-reinforced metal matrix composites can further improve the thermophysical properties of the composites. At the same time, Cu has a high melting point, which also makes Cu/diamond composite materials have a wider range of applications. Therefore, combining graphene with copper to have excellent comprehensive properties such as high thermal conductivity, high electrical conductivity, low thermal expansion, and high temperature resistance has become a research hotspot for a new generation of electronic packaging materials.

However, as far as the traditional graphene powder-reinforced metal matrix composite is concerned, the graphene powder (thermal conductivity 5300W/mK) in this composite structure is like a heat-conducting grid connected by metal aluminum (thermal conductivity 237W/mK). Islands not only increase the number of two-phase interfaces, but also make it difficult to produce synergy, making it difficult to fully exert the excellent thermal conductivity of graphene. The innovative idea of the present invention is to build a continuous graphene network skeleton in the composite material, and transform the high thermal conductivity island into a high thermal conductivity channel. However, for traditional particle-reinforced composites, the preparation of interpenetrating network structures is very difficult.

Chinese invention patent CN105112754A proposes a three-dimensional network diamond framework reinforced metal matrix composite material and its preparation method, wherein the metal three-dimensional network framework substrate is prepared by mechanical processing or braided by metal wires. However, the traditional mechanical processing method belongs to multi-dimensional processing, with many processing steps and high cost. In addition, mechanical processing is restricted by traditional mechanical processing methods and equipment, and it is difficult to finely control the internal pore size and connectivity of the three-dimensional porous framework. The method of weaving metal wires has problems such as gaps in the three-dimensional pores and complicated technological process.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a foamed graphene skeleton reinforced copper-based composite material and a preparation method. The present invention replicates the structure of the foamed metal by chemical vapor deposition technology, so that the highly thermally conductive material can be seamlessly connected It forms a fully connected whole and forms a network interpenetrating structure with the aluminum matrix, so that the composite material has excellent continuous thermal conductivity, charge conductivity and extremely low density.

The foamed graphene skeleton reinforced copper-based composite material of the present invention, the composite material includes a reinforcement body and a matrix material, the reinforcement body includes a foam skeleton substrate and a graphene reinforced layer, and the surface of the foam skeleton substrate is provided with graphene reinforcement layer; the foam skeleton substrate is selected from at least one of foam metal skeleton, foam ceramic skeleton, and foam carbon skeleton, and the matrix material is selected from copper and its alloys.

The foamed graphene skeleton reinforced copper-based composite material of the present invention, the foamed metal skeleton is selected from one of foamed nickel, foamed copper, foamed titanium, foamed cobalt, foamed tungsten, foamed molybdenum, foamed chromium, foamed iron nickel, foamed aluminum The ceramic foam skeleton is selected from foam A1 ₂ O ₃ , foam ZrO ₂ , foam SiC, foam Si ₃ N ₄ , foam BN, foam B ₄ C, foam AlN, foam WC, foam Cr ₇ C ₃ .

The foam graphene skeleton reinforced copper-based composite material of the present invention, in the foam skeleton substrate, the foam pore diameter is 0.01-10mm, the opening ratio is 40-99.9%, and the foam holes are evenly or randomly distributed; the foam skeleton is a planar structure or a three-dimensional structure three-dimensional structure.

The graphene-foamed skeleton-reinforced copper-based composite material of the present invention, the graphene-enhanced layer is selected from one of graphene film, graphene wall, graphene-coated diamond, and carbon nanotube-coated graphene.

In the present invention, the foamed graphene skeleton strengthens the copper-based composite material, and in the graphene-reinforced layer, the graphene-coated diamond refers to the in-situ growth of graphene on the diamond surface, and the graphene is perpendicular to the diamond surface to form a graphene wall;

Carbon nanotube-coated graphene refers to the catalytic growth of carbon nanotubes on the surface of graphene, and the carbon nanotubes are perpendicular to the surface of graphene to form carbon nanotube forests.

The foamed graphene skeleton reinforced copper-based composite material of the present invention is also added with reinforcing particles in the matrix material, and the reinforcing particles are selected from at least one of high thermal conductivity particles, superhard wear-resistant particles, and conductive particles; the high thermal conductivity particles are selected from At least one of diamond powder, graphene, carbon nanotubes, graphene-coated diamond microspheres, carbon nanotube-coated diamond microspheres, and carbon nanotube-coated graphene; superhard wear-resistant particles are selected from diamond powder, At least one of SiC, TiC, TiN, AlN, Si ₃ N ₄ , Al ₂ O ₃ , BN, WC, MoC, Cr ₇ C ₃ ; conductive particles selected from at least one of graphite, carbon nanotubes, and graphene kind.

In the foamed graphene skeleton-reinforced copper-based composite material of the present invention, in the composite material, the volume percentage of each component is: 40-99.9% of the matrix material, 0.01-60% of the reinforcement body, and 0-30% of the reinforcing particle volume fraction.

In the foamed graphene skeleton reinforced copper-based composite material of the present invention, in the strengthening phase, the volume fraction of the graphene strengthening layer is 0.01-80%, and the volume fraction of the foam skeleton is 0.1-20%.

The foamed graphene skeleton reinforced copper-based composite material of the present invention, in the matrix, the reinforcing body is reinforced by a single body or a multi-body array. In the matrix.

A preparation method for a foamed graphene skeleton reinforced copper-based composite material, comprising the steps of:

Step 1: Preparation of Reinforcement Body

After the foam skeleton substrate is cleaned and dried, a graphene film is grown in situ on the surface of the foam skeleton by chemical vapor deposition to obtain a reinforcement; the deposition parameters are:

Deposition of graphene film: the carbon-containing gas accounts for 0.5-80.0% of the total gas mass flow rate in the furnace; the growth temperature is 400-1200°C, and the growth pressure is 5-10 ⁵ Pa;

or

After the foam skeleton substrate is cleaned and dried, the graphene wall, graphene-coated diamond, and carbon nanotube-coated graphene are grown on the surface of the foam skeleton by chemical vapor deposition. Plasma-assisted growth, and by adding a magnetic field at the bottom of the substrate to confine the plasma near the surface of the foam skeleton, strengthen the bombardment of the plasma on the surface of the foam skeleton, make graphene grow perpendicular to the surface of the foam skeleton, form a graphene wall, and obtain a reinforcement; The deposition process is:

Deposited graphene wall: the carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; the growth temperature is 400-1200°C, the growth pressure is 5-10 ⁵ Pa; the plasma current density is 0-50mA/cm ² ; The magnetic field strength in the deposition area is 100 Gauss to 30 Tesla;

Deposition of graphene-coated diamond: first, diamond is deposited on the surface of the substrate by chemical vapor deposition technology, and the deposition parameters are: the mass flow rate of carbon-containing gas is 0.5-10%; the growth temperature is 600-1000°C, and the growth pressure is 10 ³ -10 ⁴ Pa; Then, deposit a graphene wall on the diamond surface, and graphene grows perpendicular to the diamond surface to form a graphene wall. The deposition parameters are: carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; The growth temperature is 400-1200°C, the growth pressure is 5-10 ⁵ Pa; the plasma current density is 0-50mA/cm ² ; the magnetic field strength in the deposition area is 100 Gauss to 30 Tesla;

Deposition of carbon nanotube-coated graphene: First, the graphene film is deposited on the surface of the substrate by chemical vapor deposition technology. The deposition parameters are: carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; -1200°C, the growth pressure is 5-10 ⁵ Pa; then, carbon nanotube forests are deposited on the surface of the graphene wall, and the deposition parameters are: the mass flow percentage of carbon-containing gas is 5-50%; the growth temperature is 400-1300°C, The growth pressure is 10 ³ -10 ⁵ Pa; the plasma current density is 0-30mA/cm ² ; the magnetic field strength in the deposition area is 100 Gauss to 30 Tesla;

Step 2: Composite the reinforcing body with the graphene strengthening layer and the copper matrix by pressure infiltration technology.

A method for preparing a foamed graphene skeleton reinforced copper-based composite material. In the first step, after the foamed skeleton substrate is cleaned and dried, electroplating, electroless plating, vapor deposition, magnetron sputtering, chemical vapor deposition, physical A method in vapor deposition deposits one or a composite metal layer of nickel, copper, tungsten, molybdenum, titanium, silver, chromium on the surface of the substrate, and then places a suspension of nanocrystalline and microcrystalline diamond mixed particles After heating to boiling, oscillate and disperse evenly in ultrasonic waves to obtain a foam skeleton substrate with a large number of nanocrystalline and microcrystalline diamond particles inlaid in the middle of the mesh; for the foam skeleton substrate, use chemical vapor deposition on the surface of the foam skeleton or diamond In-situ growth of graphene film, graphene wall, graphene-coated diamond, and carbon nanotube-coated graphene on the particle surface to obtain a reinforcement.

A method for preparing a foamed graphene skeleton reinforced copper-based composite material. After preparing a modified layer on the surface of the reinforced body, the pressure infiltration technology is used to compound the copper matrix; the modified layer is selected from tungsten, tungsten carbide, and molybdenum. , molybdenum carbide, chromium, chromium carbide, titanium, titanium carbide, nickel, copper, aluminum, platinum, tungsten alloys, molybdenum-based alloys, chromium-based alloys, titanium-based alloys, nickel-based alloys, copper-based alloys, aluminum-based alloys, platinum At least one of base alloys; using one of electroplating, electroless plating, vapor deposition, magnetron sputtering, chemical vapor deposition, and physical vapor deposition to prepare a modified layer on the surface of the reinforcement.

A method for preparing a foamed graphene skeleton reinforced copper-based composite material. Before depositing carbon nanotubes, one of the methods of electroplating, electroless plating, vapor deposition, magnetron sputtering, chemical vapor deposition, and physical vapor deposition is required. One or a composite catalytic layer of nickel, copper, cobalt is deposited on the surface of the substrate.

CVD is currently the most likely method to industrially prepare high-quality, large-area graphene. This patent selects metal foam or ceramic foam or carbon foam skeleton that is easy to prepare and seamlessly connected as the substrate, and uses chemical vapor deposition technology to prepare a high thermal conductivity graphene film layer on its surface to construct a three-dimensional graphene network skeleton with high thermal conductivity. Combining it with the metal matrix makes the high thermal conductivity graphene and the metal form a double-connected three-dimensional network interpenetrating structure, so that the reinforcement phase and the matrix phase maintain a continuous distribution in space, forming a continuous heat conduction channel, resulting in parallel heat conduction, thus weakening the composite The negative impact of the interface on the thermal properties of the material can not only make the reinforced phase fully exert its thermal conductivity as a whole, but also not reduce the good plasticity and toughness of the metal matrix in the composite material. At the same time, one or more of high thermal conductivity diamond powder, graphene, carbon nanotubes or high thermal conductivity ceramic particles such as SiC and AlN with reduced thermal expansion coefficient can be added to achieve further improvement of thermal and mechanical properties.

The composite material prepared by this method can completely replicate the structure of metal foam, and the high thermal conductivity material forms a fully connected whole in a seamless connection, and is evenly distributed in the composite material in the form of a three-dimensional network. Continuous thermal conductivity, charge conductivity and extremely low density make the thermal conductivity, electrical conductivity and mechanical strength of composite materials greatly improved compared with traditional composite materials, and will be a new type of multifunctional composite material with great potential. It can be widely used in thermal management, electronics, energy, transportation and other national economic fields.

Description of drawings

Accompanying drawing 1 is the schematic structural view of the foam skeleton reinforced by monomers in the matrix in the present invention.

Accompanying drawing 2 is the schematic structural diagram of the foam skeleton in the matrix distributed in parallel in lamellar form in the present invention.

Accompanying drawing 3a, accompanying drawing 3b are the structural schematic diagrams of the reinforcement of the foam skeleton in the matrix in a columnar parallel distribution in the present invention.

detailed description

The technical solution of the present invention is further described below through specific examples.

Embodiments of the present invention are carried out according to the following processes or steps:

(1) Put the foam skeleton substrate in ethanol for ultrasonic vibration cleaning, take it out and dry it for later use;

(2) Adopt a method in electroplating, electroless plating, vapor deposition, magnetron sputtering, chemical vapor deposition, physical vapor deposition to prepare intermediate transition layer on foam skeleton surface, described intermediate transition layer comprises nickel, copper, tungsten , molybdenum, titanium, silver, chromium or a composite metal layer;

(3) Mix nanocrystalline and microcrystalline diamond mixed particles, foam skeleton substrate, and solvent, heat to boiling, then place in high-power ultrasonic wave for 30 minutes and disperse evenly, then take out the foam skeleton substrate and dry it to obtain the net A foam skeleton substrate with a large number of nanocrystalline and microcrystalline diamond particles embedded in the middle of the hole;

(4) adopting hot wire chemical vapor deposition to deposit a continuous and dense graphene strengthening layer on the surface of the metal substrate, the graphene strengthening layer is selected from graphene film, graphene-coated diamond, and carbon nanotube-coated graphene at least one of

(5) Before the foam skeleton with graphene reinforced layer is combined with the matrix material, in order to improve the bonding performance of the reinforced layer and the matrix material, the surface modification treatment of the reinforced layer is required, using electroplating, chemical plating, evaporation, magnetron sputtering Preparation of tungsten, tungsten carbide, molybdenum, molybdenum carbide, chromium, chromium carbide, titanium, titanium carbide, nickel, copper, aluminum on the surface of the foam skeleton with a graphene-enhanced layer by radiation, chemical vapor deposition, and physical vapor deposition , platinum, tungsten alloy, molybdenum alloy, chromium alloy, titanium alloy, nickel alloy, copper alloy, aluminum alloy, platinum alloy at least one modified layer;

(6) The layout of the graphene foam skeleton reinforcement in the matrix after surface modification can be divided into the following three modes: a. the graphene foam skeleton is composited with the matrix as an integral reinforcement, and the composite material integrally forms a diamond/ Copper network interpenetrating structure; b. The graphene foam skeleton is composited with the matrix as a sheet-like reinforcement, and the arrangement direction of the reinforcement in the matrix is parallel; c. The graphene foam skeleton is composited with the matrix as a strip reinforcement, The arrangement direction of reinforcements in the matrix is parallel arrangement;

(7) The foam skeleton with a graphene-reinforced layer is composited with a copper matrix using pressure infiltration technology.

Embodiment one:

Foamed graphene skeleton reinforced copper-based composite material, in this example, the pore size is 0.2mm titanium foam as the substrate, the foamed graphene reinforcement accounts for 8% of the volume fraction of the composite material, first according to step (1) on the foamed titanium three-dimensional network substrate Cleaning, followed by step (2) using magnetron sputtering technology to deposit a molybdenum film with a thickness of 50nm on the surface of the foam titanium three-dimensional network skeleton as an intermediate transition layer; A foam skeleton substrate of crystalline diamond particles; (4) adopting hot wall CVD to deposit graphene film, specifically: heating to 950° C. in an atmosphere of H2 and Ar (the flow rates of H2 and Ar during the heating process were 200 and 500 mL/min respectively , the heating rate is 33°C/min), heat treatment for 10min after the furnace temperature rises to 950°C; after the heat treatment is completed, a mixed gas of CH4, H2 and Ar is introduced (the gas flow rates are respectively methane 5mL/min, hydrogen 200mL/min and argon Gas 500mL/min), start to grow graphene, the cooling rate is 100 ℃/min, and the growth time is 1h, that is, the three-dimensional network skeleton of the foamed titanium substrate graphene is obtained; then follow the step (5) before compounding with the matrix material, use vacuum Evaporation method Evaporate a layer of metal copper film in situ on the surface of the foamed graphene skeleton for surface modification, the thickness of the copper film is 100nm; The reinforcing body is set in parallel in the matrix for compounding; (7) The foam skeleton with the graphene reinforced layer is compounded with the copper matrix by vacuum extrusion casting method, and the specific process parameters are as follows: the foamed graphene skeleton preform is heated to 1000°C for 1 hour , the forming mold is heated to 800°C for 1 hour, the pure copper is melted and heated to 1250°C for 1 hour, and then degassed and slag removed; now the copper liquid is poured and the network skeleton prefabricated part is placed on the static mold, and the movable mold moves downward to close the mold. Use a die-casting vacuum machine to evacuate the mold cavity. When the vacuum degree of the mold cavity is less than 1000Pa, the extrusion head starts to pressurize, and the final casting pressure is 120MPa. After holding the pressure for 2 minutes, the mold is demoulded to obtain a foamed graphene skeleton reinforced copper matrix composite. Performance test results: thermal conductivity is 615W/(m·K).

Embodiment two:

Foamed graphene skeleton reinforced copper-based composite material, in this example, the pore size of 0.3mm nickel foam is used as the substrate, and the foamed graphene reinforcement accounts for 20% of the volume fraction of the composite material. Carry out cleaning, adopt the method for evaporation to deposit thickness be the chromium film of 300nm as the intermediate transition layer on the surface of nickel foam three-dimensional network framework by step (2) afterwards; Diamond particle foam skeleton substrate; (4) Hot wire CVD is used to deposit diamond film, deposition process parameters: hot wire distance 6mm, substrate temperature 850°C, hot wire temperature 2200°C, deposition pressure 3KPa, CH ₄ /H ₂ volume flow rate Ratio 1:99, control the deposition time to obtain a diamond film thickness of 200 μm, and obtain a three-dimensional diamond network skeleton on a nickel foam substrate, and then use plasma-assisted chemical vapor deposition on the diamond surface to grow graphene in situ on the diamond surface. During the deposition process, the foam skeleton lining Plasma-assisted growth is applied on the bottom of the substrate, and the plasma is confined near the surface of the foam skeleton by adding a magnetic field at the bottom of the substrate, and the bombardment of the plasma on the surface of the foam skeleton is strengthened, so that graphene grows perpendicular to the diamond surface, and a large amount of graphite is obtained in the mesh. Graphene-coated diamond particles with high thermal conductivity and a foam skeleton with a large number of graphene walls grown on the surface of the skeleton. The deposition parameters are: substrate temperature 800°C, deposition pressure 5.0kPa, CH4/H2 volume flow ratio 23:77, plasma current density 15mA/ cm ² ; at the same time, the growth orientation of graphene is controlled under the action of an external electric field, so that they form a graphene wall perpendicular to the diamond surface, and a strengthening layer of graphene-coated diamond film is obtained. The magnetic field strength in the deposition area is 600 gauss, and the foam is obtained. Nickel-substrate graphene coats the diamond three-dimensional network framework; then, according to step (5), before compounding with the matrix material, the method of electroplating is used to electroplate a layer of metal chromium film on the surface of the foamed graphene framework surface for surface modification, and the thickness of the chromium film is 400nm; (6) place the foamed graphene framework with chrome-plated surface in the mould, and use it as a strip-shaped reinforcing body to arrange in parallel in the matrix for compounding; (7) adopt the vacuum pressure casting method to combine the foamed framework with the graphene reinforced layer with the Copper matrix compounding, the specific process parameters are as follows: the foamed graphene skeleton preform is heated to 1020°C for 1 hour, the forming mold is heated to 840°C for 1 hour, and the copper alloy (grade T1) is melted and heated to 1260°C for 0.5 hour to degas and remove slag ; After the copper alloy liquid is poured and the punch exceeds the pouring port, the die cavity is evacuated with a die-casting vacuum machine. When the vacuum degree of the cavity is less than 1000Pa, the punch continues to pressurize, and the final casting pressure is 80MPa. After holding the pressure for 2 minutes Demoulding obtains the foamed graphene skeleton reinforced copper alloy composite material. Performance test results: the axial thermal conductivity is 925W/(m·K).

Embodiment three:

Foamed graphene skeleton reinforced copper-based composite material, in this example, tungsten foam with a pore size of 1mm is used as the substrate, and the foamed graphene reinforcement accounts for 10% of the volume fraction of the composite material. After cleaning, no intermediate transition layer is added, and the in-situ growth graphene film is directly utilized by chemical vapor deposition; then according to step (3), a foam skeleton substrate inlaid with a large number of nanocrystalline and microcrystalline diamond particles in the middle of the mesh is obtained; (4) using The graphene film was deposited by hot-wall CVD, specifically: heating to 950°C in an atmosphere of H2 and Ar (the flow rates of H2 and Ar during the heating process were 200 and 500mL/min, and the heating rate was 33°C/min), and the furnace temperature After heating to 950°C, heat treatment for 10 minutes; after the heat treatment is completed, a mixed gas of CH4, H2 and Ar is introduced (gas flow rates are respectively methane 5mL/min, hydrogen 200mL/min and argon 500mL/min) to start growing graphene, and the growth time For 1h, the cooling rate is 100°C/min, and the three-dimensional network framework of graphene on the foamed tungsten substrate is obtained; then a layer of nickel is deposited on the surface of graphene by magnetron sputtering, and then plasma-assisted chemical vapor deposition is used to catalyze the growth of carbon on the surface of graphene At the same time, under the action of an external electric field, the growth orientation of carbon nanotubes is controlled, so that they are perpendicular to the graphene surface to form a carbon nanotube forest, and a strengthening layer of carbon nanotube-coated graphene film is obtained. The deposition parameters are: methane, hydrogen The mass flow rate is 5:95; the growth temperature is 600°C, the growth pressure is 3000Pa; the plasma current density is 5mA/cm ² ; the magnetic field strength in the deposition area is 500 Gauss, and the deposition time is 2h to obtain carbon nanotube-coated graphene on a foamed tungsten substrate Three-dimensional network skeleton; then according to step (5) before being composited with matrix material, adopt the method for vacuum evaporation to vapor-deposit one deck metal titanium film on the surface of foamed graphene skeleton and carry out surface modification, and the thickness of titanium film is 350nm; (6) will The foamed diamond skeleton coated with titanium on the surface is placed in the mold, and is composited with the substrate as an overall reinforcement; (7) The foam skeleton with a graphene reinforced layer is composited with the copper substrate by vacuum air casting method, and the specific process parameters As follows: the vacuum chamber pressure is 5Pa, the heating temperature of the network skeleton and the forming mold is 840°C for 2 hours, the copper alloy (brand H96) is melted and heated at 1300°C for 1 hour, the infiltration pressure is 8MPa, the pressure is kept and cooled to 400°C, the pressure is released, and the mold to obtain composite material. Foamed graphene framework reinforced copper alloy composites. Performance test results: The overall thermal conductivity of the composite material is 815W/(m·K).

Embodiment four:

Foamed graphene skeleton reinforced copper-based composite material, in this example, the porous ceramic alumina with a pore size of 2 mm is used as the substrate, and the foamed graphene reinforcement accounts for 10% of the volume fraction of the composite material. The substrate is cleaned, and then a tungsten film with a thickness of 500nm is deposited on the surface of the foamed alumina three-dimensional network skeleton as an intermediate transition layer by using the technology of magnetron sputtering according to step (2); The foam skeleton substrate of nanocrystalline and microcrystalline diamond particles; (4) use plasma-assisted chemical vapor deposition to grow graphene in situ on the substrate surface, apply plasma-assisted growth on the foam skeleton substrate during the deposition process, and Add a magnetic field at the bottom to confine the plasma near the surface of the foam skeleton, strengthen the bombardment of the plasma on the surface of the foam skeleton, make graphene grow perpendicular to the diamond surface, and obtain a large number of graphene-coated diamond high thermal conductivity particles in the mesh and growth on the skeleton surface The foam skeleton of a large number of graphene walls, the deposition parameters are: the substrate temperature is 800°C, the deposition pressure is 5.0kPa, the volume flow ratio of CH ₄ /H ₂ is 35:65, the plasma current density is 5mA/cm ² , and the magnetic field strength in the deposition area is 700 gauss, deposition 5h; Control the growth orientation of graphene under the action of external electric field simultaneously, make them vertically form graphene wall with substrate surface, obtain foamed aluminum oxide substrate graphene three-dimensional network skeleton; Follow step (5) in afterward Before compounding with the base material, a metal tungsten-copper alloy film is electroplated on the surface of the foamed graphene skeleton by magnetron sputtering to modify the surface. The thickness of the tungsten-copper alloy film is 250nm; The foamed graphene skeleton is placed in the mold, and is composited with the matrix as an overall reinforcement arrangement; (7) the copper-silicon alloy with twice the volume of the highly thermally conductive foamed graphene skeleton is placed above the skeleton, wherein the mass content of Si is 15%, then put it into a heating furnace, and keep it at 1300°C for 30min under the protection of high-purity nitrogen to prepare a foamed graphene skeleton reinforced copper alloy composite material. The thermal conductivity of the composite material is 772W/(m·K).

Embodiment five:

Foamed diamond/carbon nanotube skeleton reinforced copper matrix composite material. In this example, foamed carbon with a pore size of 0.15 mm is used as the substrate. The foamed diamond reinforcement accounts for 30% of the volume fraction of the composite material. The substrate is cleaned, followed by step (2) using magnetron sputtering technology to deposit a chromium film with a thickness of 50 nm on the surface of the copper foam three-dimensional network skeleton as an intermediate transition layer; then according to step (3) to obtain a large number of nanocrystals embedded in the middle of the mesh and a foam skeleton substrate of microcrystalline diamond particles; step (4) adopts hot wire CVD to deposit diamond film, deposition process parameters: hot wire distance 6mm, substrate temperature 800°C, hot wire temperature 2200°C, deposition pressure 3KPa, CH ₄ / The _H2 volume flow ratio is 1:99, and the thickness of the diamond film is 300 μm by controlling the deposition time, that is, the three-dimensional network skeleton of the diamond on the foamed carbon substrate is obtained; then a layer of nickel is deposited on the diamond surface by magnetron sputtering, and then plasma-assisted chemical vapor deposition is used Catalyze the growth of carbon nanotubes on the nickel surface, and control the growth orientation of carbon nanotubes under the action of an external electric field, so that they form a carbon nanotube forest perpendicular to the graphene surface, and obtain a three-dimensional network framework of diamond/carbon nanotubes on a foamed carbon substrate. The deposition parameters are: the mass flow rate of methane and hydrogen is 10%; the growth temperature is 600°C, the growth pressure is 3000Pa; the plasma current density is 5mA/cm2; the magnetic field strength in the deposition area is 500 Gauss, and the deposition is 1h. Afterwards, according to step (5) before compounding with the matrix material, a metal tungsten carbide film is deposited on the surface of the foam diamond skeleton by vacuum evaporation in situ for surface modification, and the thickness of the tungsten carbide film is 150nm; (6) the surface The foamed diamond skeleton coated with tungsten carbide film is placed in the mold, and is used as a sheet-like reinforcement in parallel in the matrix for compounding; (7) the diamond/carbon nanotube three-dimensional network skeleton with a foamed carbon substrate and Copper matrix compounding, the specific process parameters are as follows: vacuum chamber pressure 5Pa, heating temperature of network skeleton and forming mold at 840°C for 2 hours, copper alloy (brand H96) melting heating temperature at 1260°C for 1 hour, impregnation pressure of 8MPa, holding pressure and cooling The pressure was released at 400°C, and the composite material was obtained by demoulding. Foamed diamond/graphene/carbon nanotube framework reinforced copper matrix composites. Performance test results: The overall thermal conductivity of the composite material is 1262W/(m·K).

From the thermal conductivity data obtained in the above examples, it can be seen that the thermal conductivity of the foamed graphene skeleton reinforced copper-based composite material prepared by the present invention has been greatly improved, and the thermal conductivity is as high as 1262W/mK. The composite material prepared by the present invention is complete. The structure of the foam skeleton is perfectly replicated. The high thermal conductivity material forms a fully connected whole in a seamless connection. The reinforcement phase and the matrix phase maintain a continuous distribution in the three-dimensional space, forming a network interpenetrating structure, which can effectively weaken the compound interface to the material. The influence of thermal properties can neither reduce the good plasticity and toughness of the copper matrix, but also make the reinforcement phase a whole, maximize the thermal conductivity of the reinforcement, and make the composite material have excellent continuous thermal conductivity, charge conductivity and extremely low density. The overall performance is obviously better than that of traditional copper-based composite materials. It is a potential multifunctional composite material that can be widely used in thermal management, electronics, machinery, energy, transportation and other national economic fields.

Claims (11)

1. a kind of foamed graphene skeleton reinforced copper-based composite material, it is characterized in that, described composite material comprises reinforcement, matrix material, and described reinforcement comprises foam skeleton substrate, graphene reinforced layer, and described foam skeleton substrate The surface is provided with a graphene reinforced layer; the foam skeleton substrate is selected from at least one of foam metal skeleton, foam ceramic skeleton and foam carbon skeleton, and the base material is selected from copper and copper alloy. 2. a kind of foamed graphene skeleton reinforced copper-based composite material according to claim 1, is characterized in that, described metal foam skeleton is selected from foamed nickel, foamed copper, foamed titanium, foamed cobalt, foamed tungsten, foamed molybdenum, One of foamed chromium, foamed iron-nickel, and foamed aluminum; the foamed ceramic skeleton is selected from foamed A1 ₂ O ₃ , foamed ZrO ₂ , foamed SiC, foamed Si ₃ N ₄ , foamed BN, foamed B ₄ C, foamed AlN , foam WC, foam Cr ₇ C ₃ in one. 3. A kind of foamed graphene skeleton reinforced copper-based composite material according to claim 1, characterized in that, in the foam skeleton substrate, the foam pore diameter is 0.01-10mm, the opening ratio is 40-99.9%, and the foam The holes are evenly distributed or randomly distributed; the foam skeleton is a planar structure or a three-dimensional structure. 4. a kind of foamed graphene skeleton reinforced copper matrix composite material according to claim 1, is characterized in that, described graphene strengthening layer is selected from graphene film, graphene wall, graphene coated diamond, carbon nanotube One of the coated graphene. 5. foamed graphene skeleton reinforced copper-based composite material according to claim 4, is characterized in that, in the graphene reinforced layer, graphene coating diamond refers to growing graphene in situ on the diamond surface, and graphene is perpendicular to Graphene walls are formed on the diamond surface; Carbon nanotube-coated graphene refers to the catalytic growth of carbon nanotubes on the surface of graphene, and the carbon nanotubes are perpendicular to the surface of graphene to form a carbon nanotube forest. 6. according to any one of claim 1-5, the foamed graphene skeleton reinforced copper-based composite material is characterized in that, in the base material, reinforcement particles are also added, and the reinforcement particles are selected from high thermal conductivity particles, superhard wear-resistant particles , at least one of conductive particles; the high thermal conductivity particles are selected from diamond powder, graphene, carbon nanotubes, graphene coated diamond microspheres, carbon nanotubes coated diamond microspheres, carbon nanotubes coated graphene At least one of the superhard wear-resistant particles selected from at least one of diamond powder, SiC, TiC, TiN, AlN, Si ₃ N ₄ , Al ₂ O ₃ , BN, WC, MoC, Cr ₇ C ₃ ; The conductive particles are at least one selected from graphite, carbon nanotubes and graphene. 7. The foamed graphene skeleton reinforced copper matrix composite material according to claim 6 is characterized in that, in the composite material, the volume percentage of each component is: matrix material 40-99.9%, reinforcing body 0.01-60% , the volume fraction of strengthening particles is 0-30%, and the volume percentage sum of each component is 100%. 8. foamed graphene skeleton reinforced copper matrix composite material according to claim 7, is characterized in that, in matrix, reinforcing body strengthens with monomer or multi-body array, and described multi-body array strengthens and refers to reinforcing body with Lamellar parallel distribution or columnar parallel distribution in the matrix. 9. A preparation method for a foamed graphene skeleton reinforced copper-based composite material, comprising the steps of: Step 1: Preparation of Reinforcement Body After the foam skeleton substrate is cleaned and dried, a graphene film is grown in situ on the surface of the foam skeleton by chemical vapor deposition to obtain a reinforcement; the deposition parameters are: Depositing graphene film: carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; the growth temperature is 400-1200°C, and the growth pressure is 5-10 ⁵ Pa; or After the foam skeleton substrate is cleaned and dried, the graphene wall, graphene-coated diamond, and carbon nanotube-coated graphene are grown on the surface of the foam skeleton by chemical vapor deposition. Plasma-assisted growth, and by adding a magnetic field at the bottom of the substrate to confine the plasma near the surface of the foam skeleton, strengthen the bombardment of the plasma on the surface of the foam skeleton, make graphene grow perpendicular to the surface of the foam skeleton, form a graphene wall, and obtain a reinforcement; The deposition process is: Deposited graphene wall: the carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; the growth temperature is 400-1200°C, the growth pressure is 5-10 ⁵ Pa; the plasma current density is 0-50mA/cm ² ; The magnetic field strength in the deposition area is 100 Gauss to 30 Tesla; Deposition of graphene-coated diamond: first, diamond is deposited on the surface of the substrate by chemical vapor deposition technology, and the deposition parameters are: the mass flow rate of carbon-containing gas is 0.5-10%; the growth temperature is 600-1000°C, and the growth pressure is 10 ³ -10 ⁴ Pa; Then, deposit a graphene wall on the diamond surface, and graphene grows perpendicular to the diamond surface to form a graphene wall. The deposition parameters are: carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; The growth temperature is 400-1200°C, the growth pressure is 5-10 ⁵ Pa; the plasma current density is 0-50mA/cm ² ; the magnetic field strength in the deposition area is 100 Gauss to 30 Tesla; Deposition of carbon nanotube-coated graphene: First, the graphene film is deposited on the surface of the substrate by chemical vapor deposition technology. The deposition parameters are: carbon-containing gas accounts for 0.5-80% of the total gas mass flow rate in the furnace; -1200°C, the growth pressure is 5-10 ⁵ Pa; then, on the surface of the graphene film, use one of the methods of electroplating, chemical plating, evaporation, magnetron sputtering, chemical vapor deposition, and physical vapor deposition on the surface of the substrate. After depositing one or a composite catalytic layer of nickel, copper, cobalt, carbon nanotube forest is deposited, the deposition parameters are: the mass flow percentage of carbon-containing gas is 5-50%; the growth temperature is 400-1300°C, and the growth pressure is 10 ³ -10 ⁵ Pa; the plasma current density is 0-30mA/cm ² ; the magnetic field strength in the deposition area is 100 Gauss to 30 Tesla; Step 2: Composite the reinforcing body with the graphene strengthening layer and the copper matrix by pressure infiltration technology. 10. the preparation method of a kind of foamed graphene skeleton reinforced copper-based composite material according to claim 9, is characterized in that: in the first step, after foam skeleton substrate cleaning, oven dry, adopt electroplating, electroless plating, A method in evaporation, magnetron sputtering, chemical vapor deposition, and physical vapor deposition deposits one or a composite metal layer in nickel, copper, tungsten, molybdenum, titanium, silver, and chromium on the surface of the substrate, and then places In the suspension of nanocrystalline and microcrystalline diamond mixed particles, after heating to boiling, oscillate and disperse evenly in ultrasonic waves to obtain a foam skeleton substrate inlaid with a large number of nanocrystalline and microcrystalline diamond particles in the middle of the mesh; for instant noodles The skeleton substrate adopts chemical vapor deposition to in-situ grow graphene film, graphene wall, graphene-coated diamond, and carbon nanotube-coated graphene on the surface of the foam skeleton or the surface of diamond particles to obtain a reinforcement. 11. according to claim 9 or the preparation method of a kind of foamed graphene skeleton reinforced copper matrix composite material described in claim 9 or 10, it is characterized in that: after reinforcing body surface prepares one deck modified layer, adopt pressure infiltration technology and copper substrate Composite; the modified layer is selected from tungsten, tungsten carbide, molybdenum, molybdenum carbide, chromium, chromium carbide, titanium, titanium carbide, nickel, copper, aluminum, platinum, tungsten-based alloys, molybdenum-based alloys, chromium-based alloys, titanium At least one of nickel-based alloys, nickel-based alloys, copper-based alloys, aluminum-based alloys, and platinum-based alloys; using one of electroplating, electroless plating, evaporation, magnetron sputtering, chemical vapor deposition, and physical vapor deposition A modified layer is prepared on the surface of the reinforcement.