CN107953616A - The composite construction and its preparation process of a kind of conduction graphite film - Google Patents

Abstract

The invention provides a composite structure of a heat-conducting graphite film and a preparation process thereof. The composite structure includes at least two fixed sheets and at least one layer of graphite film. Inwardly recessed grooves are provided on the surfaces of two adjacent fixed pieces facing each other; an installation space is enclosed between the two grooves, and the graphite film is installed in the installation space. The thermal conductivity of the fixed sheet is greater than that of the single-sided and double-sided adhesives used to bond the graphite film in the existing die-cutting technology. The preparation process of the composite structure includes pre-installing the graphite film in the groove of a fixed piece; setting the groove of another fixed piece on the top surface of the graphite film; The protrusions around the grooves secure the connection. The composite structure can improve the thermal conductivity of the thermally conductive graphite film along the vertical direction. At the same time, at least one side wall of the graphite film is surrounded by the raised inner wall surface, which avoids the phenomenon of falling powder on the side wall of the graphite film.

Description

Composite structure of a heat-conducting graphite film and its preparation process

technical field

The invention relates to the technical field of heat dissipation materials, in particular to a composite structure of a thermally conductive graphite film and a preparation process thereof.

Background technique

Thermally conductive graphite film is widely used in electronic products for heat dissipation due to its good thermal conductivity, for example, it is used in electronic devices such as notebook computers and mobile phones.

At present, when some of the heat-conducting graphite films in electronic equipment have a single-layer structure, the graphite film is bonded to the metal sheet by glue, and then the metal sheet is bonded to the heat sink of the electronic device; if the graphite film is multilayer In the structure, the graphite films on adjacent sides are bonded by glue, the graphite film on the bottom layer is bonded to the metal sheet by glue, and the graphite film on the top layer is bonded to a pressing sheet by glue to form a multilayer graphite film The composite structure, and then the metal sheet is bonded to the heat sink of the electronic device by glue.

Although the graphite film of the above structure is fixed on the heat sink by glue to improve the heat dissipation performance of the heat sink; however, due to the need for double-sided adhesives to be fixed between adjacent layers of graphite films, or the single-layer graphite film and the metal sheet also need double-sided adhesives However, since the thermal conductivity of the glue is much smaller than that of the graphite film, along the stacking direction perpendicular to the graphite film, the glue mixed in the graphite film will lead to a decrease in the thermal conductivity of the graphite film, especially the relative The thermal conductivity between two adjacent graphite films decreases more seriously, which affects the heat dissipation performance of the thermally conductive graphite film.

Contents of the invention

Therefore, the actual technical problem to be solved by the present invention is that the graphite film and the metal sheet, or the adjacent graphite layers are fixed by glue in the prior art, resulting in the defect of poor thermal conductivity of the graphite film.

For this reason, the present invention provides a composite structure of thermally conductive graphite film, comprising

There are at least two fixed pieces; two adjacent fixed pieces are buckled and fixed, and the surfaces of the sides facing each other are respectively provided with inwardly recessed grooves, and the two grooves are surrounded by a The installation space; correspondingly, the portion of the fixing piece located around the groove forms a protrusion; the thermal conductivity of the fixing piece is greater than that of the glue;

The thermally conductive graphite film is at least one layer; one layer of the graphite film is suitable for being installed in the installation space.

Preferably, in the composite structure of the above-mentioned heat-conducting graphite film, the graphite film has at least two layers, and the fixed sheet has at least three pieces;

In the vertical direction, all the fixing pieces are stacked, the bottom surface of the topmost fixing piece is provided with the groove, and the bottommost fixing piece is provided with the groove on the top surface. Grooves, and the grooves are respectively opened on the two side surfaces of the rest of the fixing pieces; the installation space is enclosed between the two grooves of two adjacent fixing pieces.

The graphite films are installed one by one in the installation space, and two adjacent layers of the graphite films are separated by the fixing sheet.

Further preferably, in the composite structure of the above-mentioned heat-conducting graphite film, along the width direction of the graphite film, at least one side wall of the protrusion is a first opening communicating with the outside world; or

Along the length direction of the graphite film, at least one side wall of the protrusion is a second opening communicating with the outside.

Preferably, in the composite structure of the heat-conducting graphite film, the installation space is a closed cavity, and the graphite film is surrounded by the raised inner wall surface.

Preferably, in the composite structure of the above-mentioned heat-conducting graphite film, among two adjacent fixed pieces, the protrusion of the upper fixed piece is detachably fixedly connected with the protrusion of the lower fixed piece through fasteners ;or

Among the two adjacent fixing pieces, the raised bottom surface of the upper fixing piece and the raised top surface of the lower fixing piece are bonded and fixed by heat-curing glue.

Preferably, in the composite structure of the above-mentioned heat-conducting graphite film, the fixing sheet is a metal sheet.

Further preferably, in the composite structure of the above-mentioned heat-conducting graphite film, the metal sheet is any one of copper foil, aluminum foil, silver foil, gold foil, copper-aluminum alloy, and copper-silver alloy.

Preferably, in the composite structure of the above-mentioned heat-conducting graphite film, along the vertical direction, at least one blind hole is opened on the surface of the groove opposite to its opening; the graphite film located in the groove is squeezed pressed against the blind hole, or the portion of the graphite film corresponding to the blind hole is embedded in the blind hole.

Further preferably, in the composite structure of the above-mentioned heat-conducting graphite film, there are at least two blind holes, and all the blind holes are evenly distributed on the surface of the groove.

The present invention also provides a preparation process of a composite structure of a heat-conducting graphite film, which is characterized in that it comprises the following steps:

Pre-install the graphite film in the groove of a fixed piece;

Sleeve the groove of another plate over the top of the graphite film so that the raised bottom surface around the groove of the plate rests against the raised top around the groove of the plate below on the surface;

The protrusions of two adjacent fixing pieces are fixedly connected by fasteners; or, heat-curing glue is preliminarily arranged on the bottom surface or the top surface, and when the bottom surface is against the top surface, the The protrusions of two adjacent fixed pieces are fixedly connected.

1. technical scheme of the present invention has the following advantages:

1. The composite structure of the heat-conducting graphite film provided by the present invention comprises at least two fixed sheets and at least one layer of graphite film. Inwardly recessed grooves are provided on the surfaces of two adjacent fixed pieces facing each other; an installation space is enclosed between the two grooves, and the graphite film is installed in the installation space. Since the thermal conductivity of the fixed sheet is greater than that of the glue bonded to the graphite film in the prior art, the heat of the thermally conductive film is directly transferred to the fixed sheet, and then the fixed sheet is transferred to the outside, thereby improving the thermal conductivity of the graphite film in the vertical direction. Thermal conductivity; at the same time, the graphite film is limited to the installation space surrounded by two grooves, and at least one side wall of the graphite film is surrounded by the raised inner wall surface, which avoids the phenomenon of powder dropping on the side wall of the graphite film .

2. The composite structure of the heat-conducting graphite film provided by the present invention, the graphite film has at least two layers, and the fixed sheet has at least three pieces; along the vertical direction, all the fixed sheets are stacked, and the fixed sheet located on the top layer The groove is provided on the bottom surface of the bottom surface, the groove is provided on the top surface of the bottommost fixed piece, and the grooves are respectively provided on the two side surfaces of the other fixed pieces; The installation space is enclosed between the two grooves of the two fixing pieces. The graphite films are installed one by one in the installation space, and two adjacent layers of the graphite films are separated by the fixing sheet. In this composite structure, a multi-layer graphite film is set, and the graphite film is limited in the installation space, and the graphite films of two adjacent layers are separated by the fixed sheet, thereby forming a composite structure of multi-layer graphite film and the fixed sheet, to improve Thermal conductivity of graphite films.

3. The composite structure of the heat-conducting graphite film provided by the present invention, the installation structure is a closed cavity, and the graphite film is surrounded by the inner wall surface of the groove. For the composite structure of this structure, when the graphite film is installed in the installation space, its surroundings are surrounded and isolated from the outside world; since the graphite film has a layered structure, after a period of use, the layered structure becomes loose, and its outer surface The powder will fall off, because graphite has conductive properties, when the detached powder falls on the conductive parts of the electronic equipment, the conductive parts will be short-circuited, which will affect the normal use of the electronic equipment; Surrounded by the surrounding area, even if there is powder falling, it will not fall on the conductive parts of the electronic equipment, but is limited to the installation space, thus avoiding the short circuit phenomenon of electronic equipment caused by graphite film powder falling, and improving the electronic equipment. While improving heat dissipation, it prolongs the service life of electronic equipment.

4. In the composite structure of the thermally conductive graphite film provided by the present invention, among two adjacent fixed pieces, the protrusions around the groove of the upper fixed piece and the protrusions around the groove of the lower fixed piece are detachably fixed and connected by fasteners. Two adjacent fixed pieces are detachably connected by fasteners, which facilitates the installation, disassembly and maintenance of the graphite membrane; at the same time, the fixed pieces can also be recycled.

5. In the composite structure of the heat-conducting graphite film provided by the present invention, the fixed piece is a metal piece. Further preferably, the metal sheet is any one of copper foil, aluminum foil, silver foil, gold foil, copper-aluminum alloy, and copper-silver alloy. The fixed sheet is made of metal material, which increases the thermal conductivity of the fixed sheet, further improves the thermal conductivity between two adjacent graphite films, and accelerates the overall thermal conductivity of the composite structure.

6. In the composite structure of the heat-conducting graphite film provided by the present invention, along the vertical direction, at least one blind hole is provided on the surface of the groove opposite to its opening; the graphite film positioned in the groove is covered by Extruded on the blind hole, or the part of the graphite film corresponding to the blind hole is embedded in the blind hole. The design of the blind hole makes the graphite film installed in the groove, under the action of the external extrusion process, the top surface and the bottom surface of the graphite film can be in close contact with the blind hole of the corresponding groove, and even partially embedded In the blind hole, ensure that the heat of the graphite film is directly transferred to the fixed sheet to speed up the heat conduction rate.

7. The present invention also provides a preparation process for the composite structure of any one of the above-mentioned heat-conducting graphite films, comprising the steps of: pre-installing the graphite film in the groove of a fixed piece; setting the groove of another fixed piece in the on the top surface of the graphite film, and make the raised bottom surface around the groove of the fixed piece abut against the raised top surface around the groove of the fixed piece below; The side wall of the fixed piece is fixedly connected; or, a heat-curing glue is provided on the bottom surface or the top surface of the protrusion in advance, and when the bottom surface is against the top surface, two adjacent pieces of the The fixed piece is fixedly connected.

In this preparation process, the graphite film is installed in the installation space formed by the grooves of two adjacent fixed sheets. The graphite films of adjacent layers are separated by the fixed sheet. The thermal conductivity of the fixed sheet is greater than that of the glue, so that the thermal conductivity The thermal conductivity of the film in the vertical direction is improved. At the same time, the heat-conducting film is only limited in the installation space, and only contacts or squeezes the inner wall of the groove; the protrusions of the metal sheet are connected by fasteners or heat-curing glue, which is convenient for the installation, disassembly and maintenance of the graphite film.

Description of drawings

In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the specific implementation or description of the prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

Fig. 1 is the top view of sheet metal in the composite structure of the thermally conductive graphite film provided in embodiment 1;

Fig. 2 is a left schematic view of the metal sheet in Fig. 1;

Fig. 3 is the left side structure schematic diagram (the first fixing mode) of the composite structure of the thermally conductive graphite film provided in embodiment 1;

Fig. 4 is the left side structure schematic diagram (second fixing mode) of the composite structure of the thermally conductive graphite film provided in embodiment 1;

Figure 5 is a schematic diagram of the structure on the left after the graphite film is removed from the composite structure in Figure 4;

Fig. 6 is the schematic structural view of the metal sheet positioned in the middle layer in the composite structure of the heat-conducting graphite film provided in embodiment 2;

Fig. 7 is the structural representation of the composite structure of the thermally conductive graphite film provided in embodiment 2;

Fig. 8 is another kind of structural representation of the composite structure of the thermally conductive graphite film provided in embodiment 2;

Explanation of reference signs:

1-fixed piece; 11-groove; 111-open opening; 112-blind hole; 12-protrusion; 13-installation space;

2- graphite film;

3 - Fasteners;

4- Heat curing glue.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as there is no conflict with each other.

Example 1

This embodiment provides a composite structure of a heat-conducting graphite film, as shown in FIGS. 1 to 3 , including a layer of graphite film 2 and two fixing sheets 1 . Wherein, the fixed sheet 1 is a metal sheet, such as copper foil, aluminum foil, silver foil, gold foil, copper-aluminum alloy, copper-silver alloy and the like. The thermal conductivity of metal is much greater than that of glue.

A groove 11 recessed inward is provided on one side surface of the two metal sheets, corresponding to the groove 11 , a protrusion 12 is formed on the metal sheet around the groove 11 . As shown in Figure 5, the grooves 11 of the two metal sheets are arranged oppositely, and an installation space 13 is enclosed between the two grooves 11; a layer of graphite film 2 is installed in the installation space 13, and its top surface is closely against the The top surface of the groove 11 of the upper metal sheet closely abuts against the bottom surface of the groove 11 of the lower metal sheet.

There are two ways to fix the two metal sheets. As shown in Figure 3, the first fixing method is: the bottom surface of the protrusion 12 of the upper metal sheet overlaps the top of the protrusion 12 of the lower metal sheet On the surface, the fastener 3 passes through the upper protrusion 12 and the lower protrusion 12 sequentially along the vertical direction, so as to securely connect the two metal sheets. For example, the fastener 3 is a screw, or a bolt, or a screw and so on. The detachable connection mode of the fastener 3 is adopted to facilitate the installation and removal of the metal sheet.

As shown in Figures 4 and 5, the second fixing method is: the bottom surface of the protrusion 12 of the metal sheet above and the top surface of the protrusion 12 of the metal sheet below are fixed by heat-curing glue 4 . That is, the fixing methods of the two metal sheets are all realized by fixing the protrusions 12 of the two metal sheets, and the graphite film 2 is only installed in the installation space 13, and only contacts or tightly squeezes between it and the groove 11. pressure relationship.

As shown in Figure 5, the above-mentioned installation space 13 is a non-closed cavity. Along the width direction of the graphite film 2, both side walls of the protrusion 12 are open openings 111 communicating with the outside world. When the graphite film 2 is installed on the When installed in the space 13, in the left and right directions, the end faces of the graphite film 2 communicate with the outside world; but the end faces in the front and rear directions are isolated from the outside world by the inner wall of the protrusion 12, so as to prevent the graphite film 2 from falling off on the end faces in the front and rear directions. , because the graphite film 2 has a layered structure, after a period of use, the layered structure will be fluffy, and debris will appear on the end face, but graphite has conductive properties, and the debris falls on the conductive parts of electronic equipment On the other hand, it will cause a short circuit of the electronic equipment, which will affect the normal use of the electronic equipment. Therefore, the protrusion 12 of the technical solution of the present application plays the role of wrapping, preventing the phenomenon of powder dropping on the front and rear end surfaces of the graphite film 2.

Of course, in order to prevent the powder falling phenomenon on the end faces around the graphite film 2, no open opening 111 is provided around the protrusion 12, and the installation space 13 surrounded by the grooves 11 of the two metal sheets is a closed cavity. The graphite film 2 is surrounded by the inner walls of the protrusions 12. Even if there is powder falling on the end surface of the graphite film 2, the detached debris will be confined in the installation space 13 and will not be detached from the components of the electronic device. , so as to completely avoid the short circuit problem of electronic equipment caused by the powder drop phenomenon of thermally conductive graphite film 2, while improving the thermal conductivity of graphite film, it will not affect the normal use of electronic equipment, thereby prolonging the service life of electronic equipment.

As shown in FIG. 2 , along the vertical direction, several blind holes 112 are opened on the surface opposite to the opening of the groove 11 , and the several blind holes 112 are evenly formed on the surface. For the upper metal sheet, the blind hole 112 is opened on the top surface inside the groove 11 , and for the lower metal sheet, the blind hole 112 is opened on the bottom surface inside the groove 11 . For the setting of the blind hole 112, when the graphite film 2 is placed, the graphite film 2 is pressed down by pressing technology, so that the bottom surface and the top surface of the graphite film 2 are respectively closely attached to the respective corresponding blind holes 112, even The position on the surface of the graphite film 2 opposite to the blind hole 112 is embedded in the blind hole 112, thereby ensuring that the surface of the graphite film 2 is closely attached to the bottom surface or the top surface of the groove 11, preventing the graphite film 2 from being installed in the groove 11. When inside, there is a gap between the top surface of the graphite film 2 and the bottom surface of the corresponding groove 11, and there is a gap between the bottom surface of the graphite film 2 and the top surface of the corresponding groove 11, which affects the vertical direction. The heat conduction performance between the film 2 and the metal sheet can further improve the heat conduction performance of the composite structure.

The composite structure of the heat-conducting graphite film 2 in this embodiment adopts a metal sheet whose thermal conductivity is much larger than that of the glue, and a groove 11 is provided on one side of the metal sheet, and the grooves 11 of the two metal sheets are arranged opposite to each other. An installation space 13 suitable for placing graphite film 2 is formed between the two grooves 11. Along the vertical direction, the top surface and bottom surface of graphite film 2 are respectively in contact with or closely abutting against the respective metal sheets. The fixing method of the metal sheet is connected and fixed by the protrusions 12 on each, and there is no direct fixed relationship with the graphite film 2, but only a contact relationship, so that along the vertical direction, the heat conduction film can transfer the heat on it more quickly The heat is transmitted to the metal sheet, and the metal sheet is then passed to the external environment, thereby improving the thermal conductivity of the composite structure.

Example 2

This embodiment provides a composite structure of a heat-conducting graphite film, as shown in Figure 6 and Figure 7, compared with the composite structure of a heat-conducting graphite film provided in Example 1, the only difference is:

It includes two layers of heat-conducting graphite film 2, and three metal sheets. Wherein, grooves 11 are provided on the bottom surface of the metal sheet located on the top layer, grooves 11 are provided on the top surface of the metal sheet located on the bottom layer, and grooves 11 are respectively provided on both sides of the metal sheet located in the middle. A first installation space 13 is enclosed between the groove 11 of the metal sheet on the top layer and the groove 11 on the top of the middle metal sheet, the groove 11 of the metal sheet on the bottom layer and the groove 11 on the bottom of the middle metal sheet A second installation space 13 is enclosed therebetween. Two layers of graphite films 2 are respectively installed in the first installation space 13 and the second installation space 13 . There are protrusions 12 on the top surface and the bottom surface of the middle metal sheet respectively, and the protrusions 12 on both sides are respectively connected with the protrusions 12 of the metal sheet on the top layer and the protrusions 12 of the bottom metal sheet. For example by means of heat-curing glue, or the protrusions of all layers are fixedly connected by means of connectors. Other structures are the same as those in Embodiment 1, and will not be repeated here.

In the composite structure of this embodiment, the thermal conductivity of the composite structure is further improved by arranging three layers of metal sheets and two layers of graphite film 2 to form a composite structure of double graphite film 2 .

Similarly, as shown in FIG. 8 , the composite structure may also include four layers of metal sheet and three layers of graphite film 2 . A groove 11 is provided on the bottom surface of the top metal sheet, a groove 11 is provided on the top surface of the bottom metal sheet, and a groove 11 is respectively provided on the two side surfaces of the middle metal sheet. Four layers of metal sheets are stacked, and the protrusions 12 of the four layers of metal sheets are directly fixedly connected by fasteners 3; or, the protrusions 12 of two adjacent layers of metal sheets are fixed by heat-curing 4 glue. The grooves 11 of two adjacent metal sheets enclose an installation space 13, and form three installation spaces 13 from bottom to top, and the three-layer graphite film 2 is respectively installed in one installation space 13, thus forming the three-layer graphite film 2 Composite structure.

As a further deformation, the number of layers of the graphite film 2 in the composite structure can also be four layers, five layers, six layers, seven layers, eight layers, etc., correspondingly, the metal sheet is five layers, six layers, seven layers, eight layers, etc. layer, nine layers, etc., that is, the number of layers of the graphite film 2 is n layers, and the number of layers of the corresponding metal sheet is n+1 layers. Along the vertical direction, all metal sheets are stacked and arranged, and the top layer The bottom surface of the metal sheet is provided with a groove 11, the top surface of the bottommost metal sheet is provided with a groove 11, and the two side surfaces of the remaining metal sheets are respectively provided with the groove 11; two adjacent metal sheets An installation space 13 is enclosed between the two grooves 11;

The graphite films 2 are installed in the installation space 13 in a one-to-one correspondence, and two adjacent layers of graphite films 2 are separated by a layer of metal sheet. Thus forming a composite structure of multilayer graphite film.

Example 3

This embodiment provides a composite structure of a thermally conductive graphite film. Compared with the composite structure provided in Embodiment 1 or Embodiment 2, the difference lies in:

The metal sheet can also be replaced by other fixed sheet 1, as long as the thermal conductivity of the fixed sheet 1 is greater than that of the glue. For example, iron sheet, silicon sheet and so on.

Example 4

The composite structure of a thermally conductive graphite film provided in this embodiment, compared with the composite structure provided in any one of Embodiments 1 to 3, differs in that:

The number of blind holes 112 provided on the groove 11 can be one, two, three, four, etc., and the specific number is determined according to actual needs.

As an alternative embodiment, on the surface opposite to the opening of the groove 11, the blind hole 112 may not be provided. When the groove 11 is formed, only the size of the mounting structure formed by the two grooves 11 is the same as that of the graphite film 2. Matching the dimensions along the vertical direction also enables the top and bottom surfaces of the graphite film 2 to be in close contact with the surfaces of the respective opposite grooves 11 to ensure thermal conductivity.

Example 5

This embodiment provides a composite structure of a thermally conductive graphite film. Compared with the composite structure provided by any one of Embodiments 1 to 4, the only difference is:

In addition to using fasteners 3 or heat-curing glue 4, the fixing methods of two adjacent metal sheets can also be fixed by other methods, such as spot welding, or a separate clamp is set, and the metal sheets of all layers are fixed by the clamp. The protrusion 12 is clamped and fixed.

Example 6

This embodiment provides a composite structure of a thermally conductive graphite film. Compared with the composite structure provided by any one of Embodiments 1 to 5, the only difference is:

The installation space 13 is not only a closed cavity, or an open opening in the left and right directions; an open opening communicating with the outside world can also be provided on only one side wall of the protrusion 12 .

For example, along the width direction (front and rear direction) of graphite film 2, one side wall of protrusion 12 is the second opening that communicates with the outside world, or along the length direction (left and right direction) of graphite film 2, one side of protrusion 12 The wall is an opening 111 communicating with the outside world. It is convenient for outside air to enter the installation space 13, and convective heat exchange occurs between the air and the graphite film 2, thereby improving the heat exchange efficiency.

Example 7

This embodiment provides a preparation process for a composite structure of a heat-conducting graphite film. Taking the composite structure of a single-layer graphite film 2 and a two-layer metal sheet in Example 1 as an example, it includes the following steps:

S10: install the graphite film 2 in the groove 11 on the top surface of the metal sheet of the first layer;

S20: Set the groove 11 at the bottom of the metal sheet of the second layer on the top of the graphite film 2, so that the bottom surface of the protrusion 12 around the groove 11 of the metal sheet of the second layer matches the concave surface of the metal sheet of the first layer. The top surface of the protrusion 12 around the groove 11 is against it;

S30: Fix and connect the protrusion 12 of the first layer of metal sheet to the protrusion 12 of the second layer of metal sheet by a fastener.

The composite structure of the heat-conducting graphite film 2 in this embodiment only needs to install the graphite film 2 in the installation groove 11 formed by the grooves 11 of the two metal sheets, without needing to install the entire surface of the graphite film 2 as in the prior art. The glue, in the vertical direction, enables the heat transferred by the graphite film 2 to be transferred out through the metal sheet, increasing the thermal conductivity, and the whole preparation method is simple.

As a first alternative embodiment, in step S10, heat curing glue is applied on the top surface of the protrusion 12 around the groove 11 of the metal sheet of the first layer;

In step S20, when the bottom surface of the protrusion 12 of the metal sheet of the second layer is in contact with the heat-curing glue on the top surface of the protrusion 12 of the metal sheet of the first layer and pressed, the second layer of metal sheet The protrusions 12 are bonded and fixed to the protrusions 12 on the first layer of metal sheet, and the step S30 is not required.

As a second alternative embodiment, the protrusion 12 on the first layer of metal sheet is also fixed to the protrusion 12 on the second layer of metal sheet with heat-curing glue, but in step S20, the second layer of metal sheet The bottom surface of the protrusion 12 is coated with thermosetting glue, and when the groove 11 of the second layer of metal sheet is set on the top of the graphite film 2, the thermosetting glue of the protrusion 12 on the second layer of metal sheet is just compatible with the first layer of metal sheet. If the top surface of the protrusion 12 on the metal sheet is bonded and fixed, the step S30 is not needed to securely connect the two layers of metal sheets.

In the preparation process of the composite structure in this embodiment, when the first layer of metal sheet and the second layer of metal sheet are facing and pressed together, they can be bonded and fixed by heat-curing adhesive, which further simplifies the preparation process of the composite structure.

Example 8

This embodiment provides a preparation process for a composite structure of a heat-conducting graphite film. Taking the composite structure of a three-layer graphite film 2 and a four-layer metal sheet in Example 2 as an example, it includes the following steps:

S10: installing the first layer of graphite film 2 in the groove 11 on the top surface of the bottom metal sheet;

S20: Set the groove 11 at the bottom of the second layer of metal sheet on the top of the first layer of graphite film 2, so that the bottom surface of the protrusion 12 around the groove 11 of the second layer of metal sheet is in line with the bottom surface of the bottom metal sheet The top surface of the protrusion 12 around the groove 11 abuts against it;

S25: Install the second layer of graphite film 2 in the groove 11 on the top surface of the second layer of metal sheet, and then set the groove 11 at the bottom of the third layer of metal sheet on the second layer of graphite film 2, so that the third The bottom surface of the protrusion 12 around the groove 11 of the first layer of metal sheet is against the top surface of the protrusion 12 around the groove 11 of the second layer of metal sheet;

Install the third layer of graphite film 2 in the groove 11 on the top surface of the third layer of metal sheet again, then the groove 11 at the bottom of the top layer of metal sheet is set on the third layer of graphite film 2, so that the top layer of metal sheet The bottom surface of the protrusion 12 around the groove 11 abuts against and faces the top surface of the protrusion 12 around the groove 11 of the third layer of metal sheet;

S30: Fix and connect the protrusion 12 of the bottom metal sheet, the protrusion 12 of the second layer metal sheet, the protrusion 12 of the third layer metal sheet, and the top layer metal sheet by fasteners.

The preparation process of the composite structure of the thermally conductive graphite film 2 in this embodiment embodies the preparation process of the multilayer graphite film 2 , and its essence is consistent with the preparation process of the composite structure of the first embodiment provided in Example 7.

As a modification, the preparation process of using heat-curing glue to fix the protrusions 12 of two adjacent metal sheets in the first alternative embodiment and the second alternative embodiment provided in Example 1 can also be adopted.

That is, in the composite structure with multilayer graphite film 2, the first layer of graphite film 2 is first packed into the groove 11 on the top surface of the bottom fixed sheet 1, and then the groove at the bottom of the second layer of fixed sheet 1 11 is set on the top of the first layer of graphite film 2, and so on, first install graphite film 2 on each layer of fixed sheet 1 and then install the fixed sheet 1 above it, until it is installed at the position of fixed sheet 1 on the top layer, Finally, fasteners are used to connect the protrusions 12 of the fixing sheets 1 of all layers; or when installing each layer of fixing sheets 1, heat-curing glue is used to directly bond and fix the protrusions 12 of the two adjacent layers of fixing sheets 1 . Or adopt other fixing methods, such as spot welding, when installing the fixed piece 1 of the upper layer, directly spot-weld the protrusion 12 of the fixed piece 1 to the protrusion 12 of the lower fixed piece 1 adjacent to it; or wait After all the fixed sheets 1 of all layers are installed, the protrusions 12 of the fixed sheets 1 of all layers are clamped and fixed by clamps.

Apparently, the above-mentioned embodiments are only examples for clear description, rather than limiting the implementation. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And the obvious changes or changes derived therefrom are still within the scope of protection of the present invention.

Claims (10)

1. A composite structure of thermally conductive graphite film, characterized in that, comprising The fixed pieces (1) are at least two pieces; the two adjacent fixed pieces (1) are buckled and fixed, and the surfaces of the sides facing each other are respectively provided with inwardly recessed grooves (11). An installation space (13) is enclosed between the two grooves (11); correspondingly, the portion around the groove (11) on the fixing piece (1) forms a protrusion (12); the fixing The thermal conductivity of the sheet (1) is greater than the thermal conductivity of the glue; The heat-conducting graphite film (2) is at least one layer; one layer of the graphite film (2) is suitable for being installed in the installation space (13). 2. the composite structure of heat-conducting graphite film according to claim 1, is characterized in that, described graphite film (2) is at least two layers, and described fixed piece (1) is at least three; Along the vertical direction, all the fixed pieces (1) are stacked, and the bottom surface of the fixed piece (1) on the top layer is provided with the groove (11), and the bottom surface of the fixed piece (1) on the bottom layer is provided with the groove (11). The top surface of the sheet (1) is provided with the groove (11), and the other two side surfaces of the fixed sheet (1) are respectively provided with the groove (11); two adjacent fixed sheets The installation space (13) is enclosed between the two grooves (11) of (1); The graphite films (2) are installed one by one in the installation space (13), and two adjacent layers of the graphite films (2) are separated by the fixing sheet (1). 3. the composite structure of thermally conductive graphite film according to claim 1 or 2, is characterized in that, Along the width direction of the graphite film (2), at least one side wall of the protrusion (12) is a first opening (111) communicating with the outside world; or Along the length direction of the graphite film (2), at least one side wall of the protrusion (12) is a second opening communicating with the outside. 4. The composite structure of heat-conducting graphite film according to claim 1 or 2, characterized in that, the installation space (13) is a closed cavity, and the graphite film (2) is surrounded by the protrusions (12) ) surrounded by the inner wall surface. 5. The composite structure of thermally conductive graphite film according to any one of claims 1-4, characterized in that, among two adjacent fixed pieces (1), the protrusion of the upper fixed piece (1) (12) detachably fixedly connected with the protrusion (12) of the fixed piece (1) located below by a fastener; or Among the two adjacent fixed pieces (1), the bottom surface of the protrusion (12) of the upper fixed piece (1) and the bottom surface of the protrusion (12) of the lower fixed piece (1) The top surfaces are bonded with a heat-curing adhesive. 6. The composite structure of thermally conductive graphite film according to any one of claims 1-5, characterized in that, the fixing sheet (1) is a metal sheet. 7 . The composite structure of heat-conducting graphite film according to claim 6 , wherein the metal sheet is any one of copper foil, aluminum foil, silver foil, gold foil, copper-aluminum alloy, and copper-silver alloy. 8. The composite structure of the heat-conducting graphite film according to any one of claims 1-7, characterized in that, along the vertical direction, at least one opening is provided on the surface opposite to the opening of the groove (11). Blind hole (112); the graphite film (2) located in the groove (11) is extruded on the blind hole (112), or the graphite film (2) and the blind hole The corresponding part of (112) is embedded in said blind hole (112). 9. the composite structure of heat-conducting graphite film according to claim 8, is characterized in that, There are at least two blind holes (112), and all the blind holes (112) are evenly distributed on the surface of the groove (11). 10. A preparation process for the composite structure of the heat-conducting graphite film according to any one of claims 1-9, characterized in that, comprising the steps: The graphite film (2) is installed in the groove (11) of a fixed piece (1) in advance; The groove (11) of another fixed piece (1) is sleeved on the top of graphite film (2), and makes the bottom surface of the protrusion (12) around the groove (11) of this fixed piece (1) abuts against the top surface of the protrusion (12) around the groove (11) of the fixed piece (1) located below; The protrusions (12) of two adjacent fixing pieces (1) are fixedly connected by fasteners; or, heat-curing glue is provided on the bottom surface or the top surface in advance, and the bottom surface is pressed against the bottom surface When the top surface is mentioned above, the protrusions (12) of two adjacent fixing pieces (1) are fixedly connected.