1. The utility model provides a graphite alkene reinforcing heat conduction aluminium base composite which characterized in that, includes metal aluminium layer and graphite alkene metal aluminium composite construction layer, graphite alkene metal aluminium composite construction layer is that infiltration flow metal aluminium constitutes between the graphite alkene of slice.

2. The graphene reinforced heat-conducting aluminum-based composite material as claimed in claim 1, wherein the number of layers of the graphene sheet is 1-8, and the thickness of the graphene sheet is 0.336 nm-2.7 nm.

3. The preparation method of the graphene reinforced heat-conducting aluminum-based composite material as claimed in any one of claims 1 to 2, characterized by comprising the following steps:

s01: weighing the flake graphene, the CMC and the deionized water according to a certain proportion, placing the flake graphene, the CMC and the deionized water in a kettle, and stirring the flake graphene, the CMC and the deionized water for 2 hours at a rotating speed of 100rpm to obtain a mixture;

s02: sanding the mixture obtained in the step S01 by using a sand mill to obtain graphene slurry;

s03: coating the graphene slurry obtained in the step S02 on one surface of the aluminum plate section bar, placing the aluminum plate section bar in a vacuum drying box, and carrying out vacuum drying to obtain the graphene slurry coated aluminum plate section bar;

s04: loading the graphene slurry coating aluminum plate section bar obtained in the step S03 into a clamping tool die, loading into a furnace chamber of a vacuum sintering furnace, and sealing and closing;

s05: after the step S04 is finished, vacuumizing the furnace chamber of the vacuum sintering furnace;

s06: heating the furnace chamber of the vacuum sintering furnace to 661 ℃, and keeping the temperature for 4 hours at 661 ℃;

s07: closing a furnace chamber heating heat source of the vacuum sintering furnace, naturally cooling the furnace chamber of the vacuum sintering furnace to 32 ℃, and cooling and solidifying molten metal aluminum in the graphene slurry coating aluminum plate sectional material to form the graphene reinforced heat-conducting aluminum-based composite material;

s08: slowly releasing the pressure in the furnace chamber of the vacuum sintering furnace in vacuum;

s09: and after the pressure in the furnace chamber of the vacuum sintering furnace is reduced, taking out the clamping tool die from the furnace chamber of the vacuum sintering furnace, and taking out the graphene reinforced heat-conducting aluminum-based composite material from the clamping tool die.

4. The preparation method of the graphene reinforced heat-conducting aluminum-based composite material according to claim 3, wherein the mass ratio of the total amount of the flake graphene and the CMC to the deionized water in the step S01 is 1:1, the flake graphene accounts for 60-80% of the total mass of the flake graphene and the CMC, and the CMC accounts for 20-80% of the total mass of the flake graphene and the CMC.

5. The method for preparing the graphene reinforced heat-conducting aluminum-based composite material according to claim 3, wherein the thickness of the aluminum plate profile in the step S03 is 20 μm to 900 μm, the thickness of the graphene slurry coating after vacuum drying is 5 μm to 25 μm, the vacuum degree of the vacuum drying is less than or equal to 500pa, and the temperature of the vacuum drying is 60 ℃.

6. The preparation method of the graphene reinforced heat-conducting aluminum-based composite material as claimed in claim 3, wherein the clamping tooling die in the step S04 comprises a clamping frame, a cushion block and a pressing block; the clamping frame is provided with a through clamping frame rectangular hole, the cushion block comprises four cushion block vertical faces, a cushion block upper plane and a cushion block lower plane, the pressing block comprises four pressing block vertical faces, a pressing block upper plane and a pressing block lower plane, and the cushion block, the pressing block and the clamping frame rectangular hole are assembled in a fit mode according to interference tolerance.

7. The method for preparing the graphene reinforced heat-conducting aluminum-based composite material as claimed in claim 6, wherein the step of loading the graphene slurry coated aluminum plate profile into the clamping die in step S04 is as follows:

(1) placing the graphene slurry coating aluminum plate profile on the upper plane of the cushion block and in the edge of the vertical surface of the cushion block;

(2) the rectangular hole of the clamping frame is tangent to the boundary of the vertical face of the cushion block, and the cushion block is wedged into the rectangular hole of the clamping frame;

(3) wedging the pressing block into the rectangular hole of the clamping frame, and keeping the graphene slurry coating aluminum plate sectional material clamped oppositely by the upper plane of the cushion block and the lower plane of the pressing block face to face.

8. The preparation method of the graphene reinforced heat-conducting aluminum-based composite material as claimed in claim 3, wherein in the step S05, vacuum is pumped until the vacuum degree is less than or equal to 100pa, and the vacuum degree is kept for 6 h.

9. The method for preparing the graphene reinforced heat-conducting aluminum-based composite material according to claim 3, wherein in the step S06, the vacuum degree of the furnace chamber of the vacuum sintering furnace is kept to be less than or equal to 100pa, and the temperature rise rate of the furnace chamber of the vacuum sintering furnace is 5 ℃/min.

10. The preparation method of the graphene reinforced heat-conducting aluminum-based composite material according to claim 3, wherein the step of taking out the graphene reinforced heat-conducting aluminum-based composite material from the clamping tool die in the step S09 is as follows: fixing the clamping frame, and pushing a block by adopting a hydraulic push rod to enable the pressing block, the cushion block and the clamped graphene reinforced heat-conducting aluminum-based composite material to be separated from the rectangular hole of the clamping frame; and unloading the pressing block, and collecting the graphene reinforced heat-conducting aluminum-based composite material.

Background

Graphene is an ideal reinforcement for the preparation of high performance metal matrix composites, added to aluminum substrates, ofThe mechanical and thermal properties of the aluminum matrix are expected to be greatly improved. The aluminum-based composite material has become an important composite material in metal-based composite materials due to the excellent properties of light weight, high specific strength, low thermal expansion coefficient, easy processing and the like, and is widely applied to the civil and military fields. The preparation of the existing graphene aluminum matrix composite material mainly has the following 3 problems: (1) the problem of agglomeration of graphene is solved, the graphene belongs to a two-dimensional nano material and has easy agglomeration, and the graphene and an aluminum matrix have poor wettability, so that the agglomeration phenomenon is easy to occur after the graphene is added into the aluminum matrix, and the graphene is difficult to be uniformly distributed in the aluminum matrix; (2) graphene is difficult to be uniformly distributed in an aluminum matrix, so that strong interface bonding is difficult to form in the aluminum matrix; (3) when the ball-milling mixing temperature of the graphene and the aluminum-based material is higher, an interfacial reaction is easy to generate A1₄C₃，A1₄C₃The mechanical, electrical and thermal properties of the graphene aluminum-based composite material are destroyed. Most of the existing graphene and aluminum-based materials are dispersed and mixed by ball milling, in the ball milling process, stainless steel balls and aluminum particles have mechanical effects such as impact, shearing and the like on graphene, so that the defects such as defect and fracture of the boundary of a two-dimensional nano graphene material are increased, the more the defects of the two-dimensional nano graphene material are, the poorer the mechanical, electrical, thermal, optical and other properties of the two-dimensional nano graphene material are, and even the graphene is difficult to play.

Disclosure of Invention

Aiming at the defects of the existing preparation process and graphene aluminum-based composite structure, the invention provides a graphene reinforced heat-conducting aluminum-based composite material which does not reduce the mechanical property and the electrical property of metal aluminum, enhances the heat-conducting property and has more excellent comprehensive performance, and a preparation method thereof.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a graphene reinforced heat conduction aluminum-based composite material which comprises a metal aluminum layer and a graphene metal aluminum composite structure layer, wherein the graphene metal aluminum composite structure layer is formed by a sheet-shaped graphene interpenetration metal aluminum layer.

Furthermore, the number of layers of the flake graphene is 1-8, and the thickness of the flake graphene is 0.336-2.7 nm.

The flaky graphene has excellent mechanical, electrical, thermal and optical properties, and can be uniformly distributed and embedded into an aluminum matrix, so that the electrical, mechanical and thermal properties of the aluminum matrix can be remarkably improved.

The CMC, named as sodium carboxymethyl cellulose in Chinese, plays a role of a binder in the process of preparing the graphene slurry by the technical scheme.

The deionized water is ions for removing calcium and magnesium elements, in the technical scheme, the calcium and magnesium ions are prevented from reacting with aluminum elements and carbon elements or generating impurity phases at high temperature, interface reaction is avoided, and the resistance value of the used deionized water is more than or equal to 18 megaohms.

The invention also provides a preparation method of the graphene reinforced heat-conducting aluminum-based composite material, which comprises the following steps:

s01: weighing the flake graphene, the CMC and the deionized water according to a certain proportion, placing the flake graphene, the CMC and the deionized water in a kettle, and stirring the flake graphene, the CMC and the deionized water for 2 hours at a rotating speed of 100rpm to obtain a mixture;

s02: sanding the mixture obtained in the step S01 by using a sand mill, and dispersing the agglomerated flake graphene and CMC in deionized water to obtain graphene slurry;

s03: coating the graphene slurry obtained in the step S02 on one surface of the aluminum plate section bar, placing the aluminum plate section bar in a vacuum drying oven, and carrying out vacuum drying at the vacuum degree of less than or equal to 500pa and the vacuum drying temperature of 60 ℃ to obtain the graphene slurry coated aluminum plate section bar;

s04: loading the graphene slurry coating aluminum plate section bar obtained in the step S03 into a clamping tool die, loading into a furnace chamber of a vacuum sintering furnace, and sealing and closing;

s05: after the step S04 is finished, vacuumizing the furnace chamber of the vacuum sintering furnace to be less than or equal to 100 pa;

s06: heating a furnace chamber of the vacuum sintering furnace to 661 ℃, and keeping the temperature for 4 hours at 661 ℃ to ensure that the temperature of the graphene slurry coating aluminum plate section bar in the clamping die is consistent inside and outside;

s07: closing a furnace chamber heating heat source of the vacuum sintering furnace, naturally cooling the furnace chamber of the vacuum sintering furnace to 32 ℃, and cooling and solidifying molten metal aluminum in the graphene slurry coating aluminum plate sectional material to form the graphene reinforced heat-conducting aluminum-based composite material; after a furnace chamber heating heat source of the vacuum sintering furnace is closed, the temperature of the furnace chamber of the vacuum sintering furnace is slowly reduced, the vacuum degree is continuously kept to be less than or equal to 100pa, the temperature of the liquid metal aluminum in a molten state is slowly reduced along with the temperature reduction of the furnace chamber of the vacuum sintering furnace, the liquid metal aluminum is gradually transited from a liquid state to a solid state, the liquid metal aluminum is completely solid along with the temperature continuous reduction, and after the liquid metal aluminum is completely solid, the sheet graphene is fixed by the completely solid metal aluminum to form a graphene aluminum-based composite structure, so that the graphene reinforced heat-conducting aluminum-based composite material is obtained;

s08: slowly releasing the pressure in the furnace chamber of the vacuum sintering furnace in vacuum;

s09: and after the pressure in the furnace chamber of the vacuum sintering furnace is reduced, taking out the clamping tool die from the furnace chamber of the vacuum sintering furnace, and taking out the graphene reinforced heat-conducting aluminum-based composite material from the clamping tool die.

Further, the mass ratio of the total amount of the flake graphene and the CMC to the deionized water in the step S01 is 1:1, the flake graphene accounts for 60-80% of the total mass of the flake graphene and the CMC, and the CMC accounts for 20-80% of the total mass of the flake graphene and the CMC.

Further, in the step S03, the thickness of the aluminum plate profile is 20 μm to 900 μm, the thickness of the graphene slurry coating after vacuum drying is 5 μm to 25 μm, the vacuum degree of the vacuum drying is less than or equal to 500pa, and the temperature of the vacuum drying is 60 ℃.

Drying moisture in the graphene slurry coated on the aluminum plate profile by vacuum drying; the temperature is controlled to be 60 ℃ in the drying process, the phenomenon that the viscosity of CMC (carboxy methyl cellulose) in the graphene slurry is reduced due to overhigh temperature rise is avoided at a lower temperature, the influence on the adhesive force between the graphene and an aluminum plate profile is avoided, the pressure is reduced by vacuumizing, the moisture in the graphene slurry can be evaporated at 60 ℃, the drying purpose is achieved, and the dried graphene slurry forms a laminated graphene stacked multilayer structure.

Further, the clamping tooling die in the step S04 includes a clamping frame, a cushion block and a pressing block; the clamping frame is provided with a through clamping frame rectangular hole, the cushion block comprises four cushion block vertical faces, a cushion block upper plane and a cushion block lower plane, the pressing block comprises four pressing block vertical faces, a pressing block upper plane and a pressing block lower plane, and the cushion block, the pressing block and the clamping frame rectangular hole are assembled in a fit mode according to interference tolerance.

The clamping frame, the cushion block and the pressing block are made of 0Cr25Ni20 heat-resistant stainless steel; the 0Cr25Ni20 duplex stainless steel is commonly used for manufacturing high-temperature resistant furnace tubes, has good oxidation resistance and corrosion resistance, has good creep strength due to high percentage of chromium and nickel, can continuously operate at high temperature, and has good high temperature resistance; the maximum working temperature is 1200 ℃, and the continuous use temperature is 1150 ℃.

Further, in the step S04, the step of loading the graphene slurry coated aluminum plate profile into the clamping die set includes:

(1) placing the graphene slurry coating aluminum plate profile on the upper plane of the cushion block and in the vertical plane of the cushion block;

(2) the rectangular hole of the clamping frame is tangent to the boundary of the vertical face of the cushion block, and the cushion block is wedged into the rectangular hole of the clamping frame;

(3) wedging the pressing block into the rectangular hole of the clamping frame, and keeping the graphene slurry coating aluminum plate sectional material clamped oppositely by the upper plane of the cushion block and the lower plane of the pressing block face to face.

Further, in the step S05, vacuumizing is carried out until the vacuum degree is less than or equal to 100pa, and keeping for 6 h; so that the gas molecules absorbed by the aluminum plate profile coated with the graphene slurry are completely removed.

Further, in the step S06, the vacuum degree of the furnace chamber of the vacuum sintering furnace is maintained to be less than or equal to 100pa, and the temperature rise rate of the furnace chamber of the vacuum sintering furnace is 5 ℃/min.

When the temperature of a furnace chamber of the vacuum sintering furnace is raised to 235-248 ℃, the CMC component in the graphene slurry is carbonized, and the carbonized CMC component has electrical conductivity and better thermal conductivity; when the furnace chamber of the vacuum sintering furnace is heated to 661 ℃, the graphene slurry coating aluminum plate section material aluminum material is in a molten state, the vacuum degree in the furnace chamber of the vacuum sintering furnace is kept to be less than or equal to 100pa, oxygen molecules in the furnace chamber of the vacuum sintering furnace reach a thin level, and all phase substances in the graphene slurry and metal aluminum do not have oxidation reaction.

The vacuum degree in a furnace chamber of the vacuum sintering furnace is kept to be less than or equal to 100pa, when the furnace chamber of the vacuum sintering furnace is heated to 661 ℃, the graphene slurry is coated on the aluminum material of the aluminum plate section in a molten state, liquid metal aluminum in the molten state forms gaps to slightly increase the free volume, the volume is increased by 2.5% -5%, long-distance ordered arrangement in solid aluminum disappears in the molten state, the liquid metal aluminum becomes short-distance ordered arrangement, the free volume slightly increases the thermal expansion effect, and gap seepage is formed among the laminated multi-layer structure layers of the laminated graphene.

It should be noted that although the graphene slurry coated aluminum plate profile is in a state where the graphene slurry coated aluminum plate profile is clamped by the clamping frame, the cushion block and the pressing block, the strength and the elastic modulus of the sheet graphene are 125GPa and 1100GPa respectively, the shape of the sheet graphene is not an absolute plane, the clamping frame, the cushion block and the pressing block are not enough to enable the sheet graphene to yield and deform, gaps between stacked multilayer structures of the sheet graphene still exist, seepage metal aluminum seeps to gaps between layers of the stacked multilayer structures of the sheet graphene, the sheet graphene is surrounded by molten liquid metal aluminum, and due to the fact that the mass of the graphene is smaller than that of the liquid metal aluminum, and the specific surface area of the graphene is large, a sedimentation effect is not easily formed, and therefore, the sheet graphene is suspended on the surface above the metal aluminum.

Further, the step of taking out the graphene reinforced heat-conducting aluminum-based composite material from the clamping tool die in the step S09 is as follows: fixing the clamping frame, and pushing a block by adopting a hydraulic push rod to enable the pressing block, the cushion block and the clamped graphene reinforced heat-conducting aluminum-based composite material to be separated from the rectangular hole of the clamping frame; and unloading the pressing block, and collecting the graphene reinforced heat-conducting aluminum-based composite material.

Compared with the prior art, the invention has the following advantages and beneficial effects:

(1) the metal aluminum layer of the graphene-reinforced heat-conducting aluminum-based composite material provided by the invention reserves the unique oxidation resistance, corrosion resistance, electric conductivity and heat conductivity of aluminum metal; graphene metallic aluminum composite structure layer, carbon atom of sheet graphene and method for producing the samesp²The two-dimensional geometrical shape of the two-dimensional honeycomb lattice structure formed by the closely arranged bonds is strongly coupled with the aluminum matrix material, so that the sheet graphene can conduct heat along the surface, the heat conductivity of the graphene metal aluminum composite structure layer is improved, particularly, the sheet graphene is surrounded and cured by the metal aluminum, the heat dissipation and the reduction of the thermal resistance are effectively enhanced, and the effect of enhancing the heat conduction of the graphene is achieved.

(2) When the graphene reinforced heat-conducting aluminum-based composite material provided by the invention is used for a conductive device, as the thermal conductivity of the graphene metal aluminum composite structure layer is higher than that of the metal aluminum layer, when current passes through the graphene reinforced heat-conducting aluminum-based composite material, according to the joule law:

Q＝I²Rt；

in the formula:

Q-Heat, in joules (J),

I-Current, in amperes (A),

r-resistance, in units of (Ω),

t is time in seconds(s).

Because the metal aluminum layer and the graphene metal aluminum composite structure layer have different respective resistances, the resistance of the graphene metal aluminum composite structure layer is smaller than that of the metal aluminum layer, the heat generation at the same time is different, the heat generation of the metal aluminum layer is large, the heat generation of the graphene metal aluminum composite structure layer is small, the temperature difference exists between the metal aluminum layer and the graphene metal aluminum composite structure layer when the graphene reinforced heat-conducting aluminum-based composite material is used as a conductor in a power-on state, the temperature of the graphene metal aluminum composite structure layer is lower than that of the metal aluminum layer, the graphene metal aluminum composite structure layer with the lower temperature has the function of a heat dissipation layer, and secondly, the high conductivity of the graphene is realized, the current overload capacity of the graphene metal aluminum composite structure layer is enhanced, the thermal conductivity of the graphene can reach 5300W/(m.K), and the reinforced heat dissipation effect of the graphene metal aluminum composite structure layer, the temperature rise of the graphene reinforced heat-conducting aluminum-based composite material is small when current passes through the composite material, and the function of increasing overload capacity is achieved.

(3) The graphene reinforced heat-conducting aluminum-based composite material has remarkable advantages when being used for heat dissipation devices, is a composite layered structure consisting of a metal aluminum layer and a graphene metal aluminum composite structure layer, wherein, the heat-conducting property of the graphene metal aluminum composite structure layer is obviously superior to that of the metal aluminum layer, and the graphene metal aluminum composite structure layer plays a similar heat-radiating function device ribbing effect in the integral structure of the graphene reinforced heat-conducting aluminum-based composite material, when the metal aluminum layer of the graphene reinforced heat-conducting aluminum-based composite material is in close contact with a heat-generating electronic device and has a good heat-conducting structure, the graphene metal aluminum composite structure layer has a ribbing function, has higher heat flow density at the air side or the liquid side, the heat dissipation device can be used for heat dissipation of compact spaces, particularly mobile phones, notebook computers and other mobile communication equipment.

(4) The preparation method of the graphene-reinforced heat-conducting aluminum-based composite material overcomes the defect that the traditional preparation method is easy to generate an interface reaction to generate A1 when the ball-milling mixing temperature of graphene and an aluminum-based material is higher₄C₃、A1₄C₃The mechanical, electrical and thermal properties of the graphene-based composite material are damaged.

Drawings

FIG. 1 is a schematic structural diagram of a graphene reinforced heat-conducting aluminum-based composite material according to the present invention;

FIG. 2 is a cross-sectional view taken along A-A of FIG. 1 in accordance with the present invention;

FIG. 3 is a schematic structural view of a briquette according to the present invention;

FIG. 4 is a schematic view of the construction of the clamping frame of the present invention;

FIG. 5 is a schematic view of the construction of the spacer of the present invention;

FIG. 6 is a schematic view of the clamping tooling die of the present invention;

FIG. 7 is a cross-sectional view taken along line B-B of FIG. 6 in accordance with the present invention;

FIG. 8 is a schematic flow chart of a method for preparing a graphene reinforced heat-conducting aluminum-based composite material according to the present invention;

description of reference numerals:

1. a metallic aluminum layer; 2. a graphene metal aluminum composite structure layer; 201. infiltrating metallic aluminum; 202. flake graphene; 3. clamping the frame; 301. clamping a rectangular hole of the frame; 4. cushion blocks; 401. an upper plane of the cushion block; 402. a cushion block vertical surface; 403. a cushion block lower plane; 5. briquetting; 501. pressing a lower plane; 502. pressing the vertical surface of the block; 503. and pressing the upper plane of the block.

Detailed Description

The technical solutions provided by the present invention will be described in detail with reference to specific examples, but it should be understood that the described examples are only a part of the present invention, and not all examples, and it should be understood that the following detailed description is only illustrative of the present invention and not intended to limit the scope of the present invention.

Examples

Referring to fig. 1 to 8, the present embodiment provides a graphene-reinforced heat-conducting aluminum-based composite material and a preparation method of the graphene-reinforced heat-conducting aluminum-based composite material.

A preparation method of a graphene reinforced heat-conducting aluminum-based composite material comprises the following steps:

step S01: weighing graphene, CMC and deionized water according to a certain proportion, and stirring and mixing to obtain a mixture; specifically, graphene, CMC and water are respectively weighed according to a proportion; according to the mass ratio, the graphene accounts for 70%, the CMC accounts for 30%, and deionized water with the same combination amount of the graphene and the CMC is matched; the resistance value of the deionized water is more than or equal to 18 megaohms; specifically, stirring and mixing, namely placing the graphene, the CMC and the deionized water in a stirring kettle for stirring, wherein the rotating speed of a stirring paddle is 100rmp, and the stirring time is 2 hours, so that the graphene, the CMC and the deionized water are fully mixed;

step S02: sanding the mixture obtained in the step S01 by using a sand mill, and dispersing the agglomerated flake graphene and CMC in deionized water to obtain graphene slurry; specifically, a sanding tank of the sand mill adopts corundum, sanding medium and zirconia beads;

step S03: coating the graphene slurry obtained in the step S02 on one surface of the aluminum plate section bar, placing the aluminum plate section bar in a vacuum drying box, and carrying out vacuum drying to obtain the graphene slurry coated aluminum plate section bar; specifically, the graphene slurry dispersed by sanding is coated on one surface of the aluminum plate section, the graphene slurry is coated on the aluminum plate section, the thickness of the aluminum plate section is 25 micrometers, the width of the aluminum plate section is 30mm, the aluminum plate section coated with the graphene slurry is placed in a vacuum drying oven, and the aluminum plate section coated with the graphene slurry is vacuumized, the vacuum degree is 500pa, the temperature is 60 ℃, so that the moisture in the aluminum plate section coated with the graphene slurry is dried; the temperature is controlled to be 60 ℃ in the drying process, and the thickness of the graphene slurry coating is measured to be 30 micrometers by an ellipsometer after the graphene slurry coating is dried; the thickness of the graphene slurry coating after drying is 5 μm;

step S04: loading the graphene slurry coating aluminum plate section bar obtained in the step S03 into a clamping tool die, loading into a furnace chamber of a vacuum sintering furnace, and sealing and closing;

step S05: after the step S04 is completed, vacuumizing the furnace chamber of the vacuum sintering furnace, specifically, after the step S04 is completed, vacuumizing the furnace chamber of the vacuum sintering furnace, vacuumizing the vacuum degree to 100pa, and keeping for 6 hours, so that the gas molecules adsorbed by the graphene slurry coating aluminum plate profile are completely removed;

step S06: the vacuum maintaining degree in the furnace chamber of the vacuum sintering furnace is 100pa, the furnace chamber of the vacuum sintering furnace is heated, the heating rate is 5 ℃ per minute, the temperature is raised to 661 ℃, and the temperature is maintained for 4 hours at 661 ℃, so that the temperature of the graphene slurry coating aluminum plate section in the clamping die is consistent inside and outside;

when the temperature of a furnace chamber of the vacuum sintering furnace is raised to 235-248 ℃, the CMC component in the graphene slurry is carbonized, and the carbonized CMC component has electrical conductivity and better thermal conductivity; when the furnace chamber of the vacuum sintering furnace is heated to 661 ℃, the graphene slurry coating aluminum plate section bar aluminum material is in a molten state, the vacuum degree in the furnace chamber of the vacuum sintering furnace is kept at 100pa, oxygen molecules in the furnace chamber of the vacuum sintering furnace reach a thin level, and all phase substances in the graphene slurry and metal aluminum do not have oxidation reaction;

the vacuum degree in the furnace chamber of the vacuum sintering furnace is kept at 100pa, when the furnace chamber of the vacuum sintering furnace is heated to 661 ℃, the graphene slurry coating aluminum plate section material aluminum material is in a molten state, and the molten liquid metal aluminum has a thermal expansion effect of increasing the free volume, so that gap seepage is formed among the laminated multilayer structure layers of the sheet graphene; it should be noted that although the graphene slurry coated aluminum plate profile is in a state where the clamping frame 3, the cushion block 4 and the pressing block 5 clamp the graphene slurry coated aluminum plate profile, the strength and the elastic modulus of graphene are 125GPa and 1100GPa respectively, the shape of the sheet graphene is not an absolute plane, the clamping frame 3, the cushion block 4 and the pressing block 5 have insufficient clamping force and yield deformation of the sheet graphene, and a gap between layers of the stacked multilayer structure of the sheet graphene still exists, in combination with fig. 2, the seepage metal aluminum 201 seeps to a gap between layers of the sheet graphene 202 of the stacked multilayer structure, the sheet graphene 202 is surrounded by the liquid metal aluminum in a molten state, and meanwhile, because the mass of the graphene is less than that of the liquid metal aluminum, and the specific surface area of the graphene is large, a sedimentation effect is not easily formed, and therefore, the sheet graphene 202 is suspended on the upper surface of the metal aluminum 201;

step S07: turning off a furnace chamber heating power supply of the vacuum sintering furnace; after a furnace chamber heating heat source of the vacuum sintering furnace is closed, the temperature of the furnace chamber of the vacuum sintering furnace is slowly reduced, the vacuum degree is continuously kept at 100pa, along with the reduction of the temperature of the furnace chamber of the vacuum sintering furnace, the temperature of liquid metal aluminum in a molten state is slowly reduced, the liquid metal aluminum is gradually transited from a liquid state to a solid state, along with the continuous reduction of the temperature, the liquid metal aluminum is completely solid, and after the liquid metal aluminum is completely solid, the sheet graphene 202 is fixed by the completely solid metal aluminum to form a graphene aluminum-based composite structure, namely a graphene aluminum-based composite material;

step S08: vacuum pressure relief is carried out in the furnace chamber of the vacuum sintering furnace, and negative pressure in the furnace chamber of the vacuum sintering furnace is slowly released through a pressure release valve of the vacuum sintering furnace;

step S09: after negative pressure relief in a furnace chamber of the vacuum sintering furnace, taking out the clamping tool die from the furnace chamber of the vacuum sintering furnace, and then taking out the graphene reinforced heat-conducting aluminum-based composite material from the clamping tool die, specifically, after negative pressure relief in the furnace chamber of the vacuum sintering furnace, taking out the graphene aluminum-based composite material clamped by the clamping frame 3, the cushion block 4 and the press block 5 from the furnace chamber of the vacuum sintering furnace; fixing the clamping frame 3, and pushing the block 5 by using a hydraulic push rod to enable the graphene aluminum-based composite material clamped by the block 5 and the cushion block 4 to be separated from the rectangular hole 301 of the clamping frame; and (3) unloading the pressing block 5, collecting the graphene composite aluminum substrate profile, namely the graphene reinforced heat-conducting aluminum-based composite material, and measuring the thickness of the graphene reinforced heat-conducting aluminum-based composite material to be 30 micrometers by using an ellipsometer.

Specifically, the clamping tooling die comprises a clamping frame 3, a cushion block 4 and a pressing block 5; the cushion block 4 comprises 4 cushion block vertical edges 402, a cushion block upper plane 401 and a cushion block lower plane 403; a through clamping frame rectangular hole 301 is formed in the clamping frame 3; the pressing block 5 comprises a pressing block lower plane 501, a pressing block vertical plane 502 and a pressing block upper plane 503; the cushion block 4 and the pressing block 5 are assembled with the clamping frame rectangular hole 301 according to interference tolerance.

Specifically, with reference to fig. 3, 4, 5, 6, and 7, the graphene slurry-coated aluminum foil subjected to the vacuum drying process of step S03 is loaded into a clamping jig according to the following procedure:

(1) placing the graphene slurry coating aluminum plate profile on the cushion block upper plane 401 and within the edges of the four cushion block vertical surfaces 402;

(2) then, the rectangular hole 301 of the clamping frame 3 is filled; the four cushion block vertical surfaces 402 of the cushion block 4 are tangent to the boundary of the clamping frame rectangular hole 301, are assembled according to interference tolerance fit, and are wedged into the clamping frame rectangular hole 301 for assembly to achieve expansion fit;

(3) then wedging the pressing block 5 into the clamping frame rectangular hole 301, enabling the boundary of the clamping frame rectangular hole 301 to be tangent to the boundaries of the four vertical faces 502 of the pressing block 5 and assembled according to interference tolerance fit, wedging the pressing block into the clamping frame rectangular hole 301 for assembly, and achieving expansion fit; the upper plane 401 of the cushion block and the lower plane 501 of the pressing block are used for clamping the graphene slurry coating aluminum plate section in a face-to-face opposite mode.

Specifically, the clamp frame 3, the spacer 4, and the briquette 5 are made of 0Cr25Ni20 heat-resistant stainless steel.

Performance testing

Comparing and testing the current overload temperature characteristics of the graphene reinforced heat-conducting aluminum-based composite material prepared in the embodiment with that of a pure aluminum material, wherein the testing steps are carried out according to the following steps:

step 1, connecting 30v alternating current at two ends of an aluminum plate sectional material (the size is 30 mu m in thickness, 30mm in width and 290mm in length) and controlling a switch;

step 2, connecting two ends of the graphene reinforced heat-conducting aluminum-based composite material (with the dimensions of 25 microns of the metal aluminum layer, 5 microns of the graphene metal aluminum composite structure layer, 30mm of width and 290mm of length) prepared in the embodiment with 30v alternating current for on-off control;

step 3, connecting two ends of the aluminum plate profile with a 30v alternating current port to connect a fuse tester;

step 4, connecting two ends of the graphene reinforced heat-conducting aluminum-based composite material with a 30v alternating current port to connect with a fuse tester;

step 5, starting the fuse tester to electrify, and recording the current A;

step 6, recording time;

step 7, recording the corresponding temperature of the surfaces of the aluminum plate section and the graphene reinforced heat-conducting aluminum-based composite material with time, and recording the fusing time of the aluminum plate section; the results are shown in Table 1.

TABLE 1

The technical means disclosed in the invention scheme are not limited to the technical means disclosed in the above embodiments, but also include the technical scheme formed by any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and such improvements and modifications are also considered to be within the scope of the present invention.