Preparation method of novel heat dissipation material with high thermal conductivity in horizontal and vertical directions

Abstract

The invention discloses a preparation method of a novel heat dissipation material with high thermal conductivity in horizontal and vertical directions, which comprises the following steps: preparing crystalline flake graphite into graphene oxide, and dispersing and pulping; the graphene oxide slurry is dried to form a semi-solid state, a copper net is laid on a jig, and the semi-solid graphene slurry is laid into the jig and covers the copper net; then compacting and drying are carried out; performing high-temperature baking and calendaring to form a radiating fin; according to the invention, the graphene oxide and the copper net are used as core materials for hot press molding, and the X-Y plane high heat conductivity coefficient of high heat conductivity of the graphene and the high heat conductivity of the copper material in the vertical direction are combined, so that the X-Y-Z three-dimensional high-heat-conductivity novel composite heat dissipation material is realized; the X-Y-Z three-dimensional high heat conduction characteristic is considered, the Z-axis heat conduction performance is improved compared with a traditional graphite sheet, and the X-Y plane heat conduction performance is improved compared with a common metal material; and meanwhile, the problem of instant heating and heat conduction of a high-power heat source is solved, and the heat dissipation problem which cannot be solved by a traditional cooling fin in a limited structure space is solved.

Description

Technical Field

[0001] The present invention relates to the technical field related to heat dissipation materials, and in particular to a method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions. Background Art

[0002] Graphene film is one of the most promising heat dissipation materials. It has extremely high thermal conductivity and thermal radiation coefficient, and good flexibility, and can be widely used in various heat dissipation products. However, the graphene film has high thermal conductivity in the XY plane, but poor thermal conductivity in the vertical direction of the copper material. This makes it impossible for the graphene film to simultaneously take into account the high thermal conductivity in the XYZ axis. The heat dissipation capacity of the instantaneous high-heating components is limited, and the heat cannot be dissipated in time. Summary of the invention

[0003] In order to solve the defects of the prior art that the high thermal conductivity in the XYZ axis cannot be taken into account at the same time, the heat dissipation capacity on the instantaneous high heating element is limited, and the heat dissipation cannot be carried out in time, the present invention provides a preparation method of a new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions, comprising the following steps:

[0006] Step 1, preparing graphene oxide from flake graphite and dispersing and slurrying it;

[0007] Step 2: Dry the graphene oxide slurry to form a semi-solid state, lay a copper mesh on the jig, and spread the semi-solid graphene slurry into the jig and cover the copper mesh;

[0008] Step 3: compact and dry.

[0009] Step 4, high temperature baking and rolling to form a heat sink.

[0010] As a preferred technical solution of the present invention, the bottom of the heat sink in step 2 is a copper mesh, and a graphene layer is arranged on the upper surface of the copper mesh, and the copper mesh is provided with vertically upward thermal conductive ridges embedded in the graphene layer, and the side walls of the thermal conductive ridges are provided with multiple perforations; the height of the thermal conductive ridges is less than the thickness of the graphene layer.

[0011] As a preferred technical solution of the present invention, the jig in step 2 includes a jig body, a molding groove is provided inside the jig body, and a positioning mechanism for positioning the copper mesh is provided at the bottom of the molding groove.

[0012] As a preferred technical solution of the present invention, the positioning mechanism includes a through hole arranged on the jig body and connected to the bottom of the forming groove, the through holes are provided with four and distributed at the four corners of the forming groove, and a telescopic rod that can be telescoped along the through hole is provided in the through hole, and an expansion block is provided at the front end of the telescopic rod, and the expansion block can pass through the mesh of the copper mesh when expanded, and the expansion block cannot pass through the mesh after expansion; and a contraction mechanism for driving the telescopic rod to move is provided in the jig body.

[0013] As a preferred technical solution of the present invention, the expansion block includes a positioning tube at the top of the telescopic rod, and a plug rod moving along the positioning tube is provided in the positioning tube, and a guide block is provided at the end of the plug rod, and the guide block is capable of passing through the mesh of the copper mesh, and the top of the guide block is a blunt end;

[0014] A plurality of arch springs are provided at the end of the positioning tube and the bottom end of the guide block, and an ellipsoidal clamping block is formed between the plurality of arch springs. The insertion rod passes through the bottom of the telescopic rod, and a moving mechanism for driving the insertion rod to be telescopic is provided on the bottom plate.

[0015] As a preferred technical solution of the present invention, the moving mechanism includes a screw rod arranged on the base plate, the screw rod is provided with a sliding block moving along the screw rod, and one side of the sliding block is tightly attached to the base plate; the sliding block is provided with an inclined surface, the bottom end of the insertion rod is connected via a connecting frame, a return spring is provided between the connecting frame and the base plate, and the connecting frame is provided with a push block cooperating with the sliding block, the push block is provided with a guide slope cooperating with the inclined surface, and the base plate is provided with a driving motor that drives the screw rod to rotate.

[0016] As a preferred technical solution of the present invention, a double-sided adhesive layer is provided at the bottom of the copper mesh, a release paper is provided on the surface of the double-sided adhesive layer, and an insulating film is provided on the surface of the graphene layer.

[0017] The beneficial effects of the present invention are:

[0018] 1. The preparation method of the new type of heat dissipation material with high thermal conductivity in horizontal and vertical directions is to hot-press graphene oxide and copper mesh as core materials, and combine the high thermal conductivity of graphene in the XY plane and the high thermal conductivity of copper in the vertical direction to achieve a new type of composite heat dissipation material with XYZ three-dimensional high thermal conductivity; taking into account the three-dimensional high thermal conductivity of XYZ, the thermal conductivity of the Z axis is improved compared with traditional graphite sheets, and the thermal conductivity of the XY plane is improved compared with general metal materials; at the same time, it also solves the problem of instantaneous heat conduction of high-power heat sources, and solves the heat dissipation problem that traditional heat sinks in limited structural space cannot solve.

[0019] 2. In the preparation method of this new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions, a thermal conductive ridge is provided on the copper mesh and is embedded in the graphene layer, and a plurality of perforations are provided on the side wall of the thermal conductive ridge; the height of the thermal conductive ridge is less than the thickness of the graphene layer, so that the copper mesh contacts the heating surface to conduct heat, and the thermal conductive strip assists in the vertical heat conduction, and then through the adjacent contacting graphene oxide, the high thermal conductivity of graphene is utilized to quickly distribute the heat, thereby achieving effective cooling.

[0020] 3. In the preparation method of this new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions, the heat sink is formed by setting a specific fixture, wherein a positioning mechanism for positioning the copper mesh is provided at the bottom of the molding groove, so that the copper mesh is unfolded in the molding groove. After the semi-solid graphene slurry is placed in the molding groove, it will not be wrinkled together, but the copper mesh cannot be unfolded horizontally, which is not conducive to overall heat dissipation.

[0021] 4. In the preparation method of this new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions, a specific positioning mechanism is set to position the copper mesh. After the semi-solid graphene slurry is placed in the molding groove, the copper mesh is horizontally unfolded. When the graphene slurry is pressed into shape, the positioning mechanism is taken out to release the positioning effect on the copper mesh, so that the bottom surface of the heat sink blank after molding is a horizontal plane. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0023] In the attached picture:

[0024] Figure 1 It is a schematic flow chart of a method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to the present invention;

[0025] Figure 2 It is a schematic diagram of the heat sink structure of a method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to the present invention;

[0026] Figure 3 It is a structural schematic diagram of a jig for a method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to the present invention;

[0027] Figure 4 It is a schematic diagram of the installation of a positioning mechanism of a method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to the present invention;

[0028] Figure 5 yes Figure 4 The enlarged schematic diagram at A in the middle;

[0029] Figure 6 It is a structural schematic diagram of a shrinking mechanism of a method for preparing a new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions;

[0030] Figure 7 It is a structural schematic diagram of a sliding block of a method for preparing a new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions;

[0031] Figure 8 The present invention is a schematic diagram of the structure of an insulating film of a method for preparing a new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions.

[0032] In the figure: 1. copper mesh; 2. graphene layer; 3. heat-conducting convex strip; 4. perforation; 6. fixture body; 7. forming groove; 8. positioning mechanism; 9. through hole; 10. telescopic rod; 11. expansion block; 12. contraction mechanism; 13. bottom plate; 14. electric push rod; 15. positioning tube; 16. insertion rod; 17. guide block; 18. arch spring; 19. moving mechanism; 20. screw rod; 21. sliding block; 22. inclined plane; 23. connecting frame; 24. reset spring; 25. push block; 26. guide slope; 27. driving motor; 28. double-sided adhesive layer; 29. ​​release paper; 30. insulating film. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0034] Example: Figure 1-8 As shown, the present invention provides a method for preparing a novel heat dissipation material having high thermal conductivity in both horizontal and vertical directions, comprising the following steps:

[0035] Step 1, preparing graphene oxide from flake graphite and dispersing and slurrying it;

[0036] Step 2: Dry the graphene oxide slurry to form a semi-solid state, lay a copper mesh on the jig, and spread the semi-solid graphene slurry into the jig and cover the copper mesh;

[0037] Step 3: compact and dry.

[0038] Step 4, high temperature baking and rolling to form a heat sink. This method for preparing a new type of heat sink material with high thermal conductivity in both horizontal and vertical directions is to hot-press graphene oxide and copper mesh 1 as core materials, combining the high thermal conductivity of graphene in the XY plane and the high thermal conductivity of copper in the vertical direction to achieve a new type of composite heat sink with high thermal conductivity in XYZ three-dimensional space. Taking into account the high thermal conductivity of XYZ three-dimensional space, it improves the thermal conductivity of the Z axis compared to traditional graphite sheets and the thermal conductivity of the XY plane compared to general metal materials. At the same time, it also solves the problem of instantaneous heat conduction of high-power heat sources and solves the heat dissipation problem that traditional heat sinks in limited structural spaces cannot solve.

[0039] Wherein, the bottom of the heat sink in step 2 is a copper mesh 1, and a graphene layer 2 is arranged on the upper surface of the copper mesh 1, and a heat-conducting convex strip 3 is arranged on the copper mesh 1 and is embedded in the graphene layer 2, and a plurality of perforations 4 are arranged on the side wall of the heat-conducting convex strip 3; the height of the heat-conducting convex strip 3 is less than the thickness of the graphene layer 2. A heat-conducting convex strip 3 is arranged on the copper mesh 1 and is embedded in the graphene layer 2, and a plurality of perforations 4 are arranged on the side wall of the heat-conducting convex strip 3; the height of the heat-conducting convex strip 3 is less than the thickness of the graphene layer 2, so that the copper mesh 1 contacts the heating surface to conduct heat, and the heat-conducting strip assists in conducting heat in the vertical direction, and then through the adjacent contacting graphene oxide, the heat is quickly evenly distributed by utilizing the high thermal conductivity of graphene, thereby achieving effective cooling.

[0040] Among them, the jig in step 2 includes setting a jig body 6, the interior of the jig body 6 is provided with a molding groove 7, and the bottom of the molding groove 7 is provided with a positioning mechanism 8 for positioning the copper mesh 1. The heat sink is formed by setting a specific jig, wherein the bottom of the molding groove is provided with a positioning mechanism for positioning the copper mesh, so that the copper mesh is unfolded in the molding groove, and after the semi-solid graphene slurry is placed in the molding groove, it will not be wrinkled together, but the copper mesh cannot be horizontally unfolded, which is not conducive to overall heat dissipation.

[0041] The positioning mechanism 8 includes a through hole 9 provided on the fixture body 6 and connected to the bottom of the forming groove 7. There are four through holes 9, which are distributed at the four corners of the forming groove 7. A telescopic rod 10 is provided in the through hole 9 and can be extended and retracted along the through hole 9. An expansion block 11 is provided at the front end of the telescopic rod 10. The expansion block 11 can pass through the mesh of the copper mesh 1 when expanding. After expansion, the expansion block 11 cannot pass through the mesh; and a contraction mechanism 12 for driving the telescopic rod 10 to move is provided in the fixture body 6. By setting a specific positioning mechanism for positioning the copper mesh, the copper mesh 1 is horizontally unfolded after the semi-solid graphene slurry is placed in the forming groove. When the graphene slurry is pressed and formed, the positioning mechanism is taken out to release the positioning effect on the copper mesh 1, so that the bottom surface of the heat sink blank after forming is a horizontal plane.

[0042] The retracting mechanism 12 includes a bottom plate 13 that connects the telescopic rod 10 as a whole, and an electric push rod 14 is provided between the bottom plate 13 and the bottom of the fixture body 6 .

[0043] Among them, the expansion block 11 includes a positioning tube 15 set at the top of the telescopic rod 10, and the positioning tube 15 is provided with an insertion rod 16 that moves along the positioning tube 15, and the end of the insertion rod 16 is provided with a guide block 17, and the guide block 17 is capable of passing through the mesh of the copper net 1, and the top of the guide block 17 is a blunt end to avoid stabbing the staff.

[0044] A plurality of arch spring pieces 18 are provided at the end of the positioning tube 15 and the bottom end of the guide block 17, and an ellipsoidal block is formed between the plurality of arch spring pieces 18. The insertion rod 16 passes through the bottom of the telescopic rod 10, and a moving mechanism 19 for driving the insertion rod 16 to extend and retract is provided on the bottom plate 13.

[0045] The moving mechanism 19 includes a screw rod 20 disposed on the bottom plate, a sliding block 21 moving along the screw rod 20 is disposed on the screw rod 20, and one side of the sliding block 21 is tightly attached to the bottom plate 13; the sliding block 21 is provided with an inclined surface 22, the bottom end of the insertion rod 16 is connected via a connecting frame 23, a return spring 24 is disposed between the connecting frame 23 and the bottom plate 13, and a push block 25 cooperating with the sliding block 21 is disposed on the connecting frame 23, a guide slope 26 cooperating with the inclined surface 22 is disposed on the pushing block 25, and a driving motor 27 driving the screw rod to rotate is disposed on the bottom plate. The sliding block 21 drives the connecting frame 23 to move up and down, thereby adjusting the expansion block 11 to expand and contract.

[0046] A double-sided adhesive layer 28 is provided at the bottom of the copper mesh 1, and a release paper 29 is provided on the surface of the double-sided adhesive layer 28, and an insulating film 30 is provided on the surface of the graphene layer 2, which plays an insulating role.

[0047] The thickness of the copper mesh 1 is 30-50 um. The thickness of the graphene layer 2 is 0.3-2 mm.

[0048] When working, the preparation method of the new type of heat dissipation material with high thermal conductivity in both horizontal and vertical directions will perform hot pressing molding with graphene oxide and copper mesh 1 as core materials, combining the high thermal conductivity of graphene in the XY plane and the high thermal conductivity of copper in the vertical direction to realize a new type of composite heat dissipation material with XYZ three-dimensional high thermal conductivity; taking into account the XYZ three-dimensional high thermal conductivity characteristics, the thermal conductivity of the Z axis is improved compared with traditional graphite sheets, and the thermal conductivity of the XY plane is improved compared with general metal materials; at the same time, it also solves the problem of instantaneous heat conduction of high-power heat sources, and solves the heat dissipation problem that traditional heat sinks in limited structural spaces cannot solve.

[0049] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions, characterized in that: The steps include: Step 1, preparing graphene oxide from flake graphite and dispersing and slurrying it; Step 2: Dry the graphene oxide slurry to form a semi-solid state, lay a copper mesh on the jig, and spread the semi-solid graphene slurry into the jig and cover the copper mesh; Step 3: compact and dry. Step 4, high temperature baking and rolling to form a heat sink.

2. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 1, characterized in that: The bottom of the heat sink in step 2 is a copper mesh (1), and a graphene layer (2) is arranged on the upper surface of the copper mesh (1), and a heat-conducting ridge (3) is arranged on the copper mesh (1) and is vertically upward and embedded in the graphene layer (2), and a plurality of perforations (4) are arranged on the side wall of the heat-conducting ridge (3); the height of the heat-conducting ridge (3) is less than the thickness of the graphene layer (2).

3. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 1, characterized in that: The jig in step 2 comprises a jig body (6), a molding groove (7) is provided inside the jig body (6), and a positioning mechanism (8) for positioning the copper mesh (1) is provided at the bottom of the molding groove (7).

4. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 3, characterized in that: The positioning mechanism (8) comprises a through hole (9) arranged on the jig body (6) and connected to the bottom of the forming groove (7); four through holes (9) are provided and distributed at four corners of the forming groove (7); a telescopic rod (10) is provided in the through hole (9) and is telescopic along the through hole (9); an expansion block (11) is provided at the front end of the telescopic rod (10); the expansion block (11) can pass through the mesh of the copper mesh (1) when expanding, and cannot pass through the mesh after expansion; and a contraction mechanism (12) is provided in the jig body (6) for driving the telescopic rod (10) to move.

5. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 4, characterized in that: The retracting mechanism (12) comprises a bottom plate (13) which connects the telescopic rod (10) as a whole, and an electric push rod (14) is provided between the bottom plate (13) and the bottom of the fixture body (6).

6. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 5, characterized in that: The expansion block (11) comprises a positioning tube (15) at the top of the telescopic rod (10), and a plug rod (16) is arranged inside the positioning tube (15) and moves along the positioning tube (15), and a guide block (17) is arranged at the end of the plug rod (16), and the guide block (17) is capable of passing through the mesh of the copper mesh (1), and the top of the guide block (17) is a blunt end; A plurality of arch spring pieces (18) are provided at the end of the positioning tube (15) and the bottom end of the guide block (17), and an ellipsoidal block is formed between the plurality of arch spring pieces (18). The insertion rod (16) passes through the bottom of the telescopic rod (10), and a moving mechanism (19) for driving the insertion rod (16) to extend and retract is provided on the bottom plate (13).

7. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 6, characterized in that: The moving mechanism (19) comprises a screw rod (20) arranged on a bottom plate, a sliding block (21) moving along the screw rod (20) is arranged on the screw rod (20), and one side of the sliding block (21) is tightly attached to the bottom plate (13); an inclined surface (22) is arranged on the sliding block (21), the bottom end of the insertion rod (16) is connected via a connecting frame (23), a return spring (24) is arranged between the connecting frame (23) and the bottom plate (13), and a push block (25) cooperating with the sliding block (21) is arranged on the connecting frame (23), and a guide slope (26) cooperating with the inclined surface (22) is arranged on the push block (25), and a driving motor (27) driving the screw rod to rotate is arranged on the bottom plate.

8. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 2, characterized in that: A double-sided adhesive layer (28) is provided at the bottom of the copper mesh (1), a release paper (29) is provided on the surface of the double-sided adhesive layer (28), and an insulating film (30) is provided on the surface of the graphene layer (2).

9. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 2, characterized in that: The thickness of the copper mesh (1) is 30-50 um.

10. The method for preparing a novel heat dissipation material with high thermal conductivity in both horizontal and vertical directions according to claim 2, characterized in that: The thickness of the graphene layer (2) is 0.3-2 mm.

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