Disclosure of Invention
First, the technical problem to be solved
The invention aims to solve the defects of low heat dissipation efficiency, damage to peripheral devices caused by heat and the like of the existing heat dissipation structure.
(II) technical scheme
In order to solve the technical problems, the invention provides a heat dissipation lamination structure, which comprises at least two composite heat dissipation layers stacked in sequence, wherein each composite heat dissipation layer comprises a back adhesive layer, a metal foil layer and a nonmetal layer stacked in sequence.
According to a preferred embodiment of the present invention, the heat dissipation device further comprises a protection layer, wherein the protection layer is wrapped outside each composite heat dissipation layer.
According to a preferred embodiment of the present invention, the nonmetallic layer is a graphene-based material.
According to a preferred embodiment of the present invention, a liquid metal layer is further included, formed between the metal foil layer and the non-metal layer.
According to a preferred embodiment of the invention, the melting point of the liquid metal layer is between 40 and 150 degrees and the thickness is between 1 and 30 μm.
According to a preferred embodiment of the invention, the liquid metal layer is embedded on and flush with the surface of the metal foil layer facing the non-metal layer.
According to a preferred embodiment of the invention, the liquid metal layer is embedded in and embedded in a surface of the metal foil layer facing the non-metal layer.
According to a preferred embodiment of the invention, the metal foil layer is provided with depressed grooves or pits on its surface facing the non-metal layer, said grooves or pits being regularly arranged in a plane direction perpendicular to the heat transfer direction.
According to a preferred embodiment of the present invention, the surface of the metal foil layer facing the nonmetallic layer is provided with depressed grooves or pits, and capillary structures are formed at the bottoms and sides of the pits or grooves.
The invention also provides a method for manufacturing the heat dissipation laminated structure and a corresponding heat radiator.
(III) beneficial effects
The invention can obviously improve the heat radiation efficiency of the radiator and reduce the damage of heat to peripheral devices.
Detailed Description
The present invention will be further described in detail below with reference to specific embodiments and with reference to the accompanying drawings, in order to make the objects, technical solutions and advantages of the present invention more apparent.
Fig. 1 is a schematic structural view of a first embodiment of a heat dissipation lamination structure of the present invention. As shown in fig. 1, the heat dissipation laminated structure of the present invention includes a backing layer 11, a metal foil layer 12 and a non-metal layer 13 from bottom to top (the direction shown in the figure is not limited in the stacking direction in practical application). The backing adhesive layer 11 may be a heat conductive adhesive with a high heat conductivity coefficient, such as silica gel. The metal foil layer 12 can be of various room temperature solid state metals including copper, aluminum, tin, and the like. In the present invention, the nonmetallic layer 13 is preferably a graphene-based material, although a carbon nanotube film, a graphite fiber, or the like may be used.
According to a preferred embodiment of the present invention, the heat dissipation laminated structure of this embodiment may further be coated with a protective layer (not shown in the figure), which may be a metal foil layer or a PET layer, or a composite protective layer formed by combining a metal foil layer and a PET layer, and the metal foil layer is, for example, an aluminum foil layer.
According to the present invention, the thickness of the backing layer 11 is preferably 5 μm to 80 μm, the thickness of the metal foil layer 12 is between 10 μm to 100 μm, and the thickness of the non-metal layer 13 is between 5 μm to 80 μm.
In preparing the above heat dissipating laminate structure, a backing layer 11 may be applied on a substrate by coating, spraying, or the like, and then a metal foil layer 12 may be adhered on the backing layer. Finally, a non-metallic layer 13 is applied to the metal foil layer.
Fig. 2 is a schematic structural diagram of a second embodiment of the heat dissipation lamination structure of the present invention. As shown in fig. 2, the heat dissipation laminated structure of this embodiment is a composite structure, i.e. the backing adhesive layer 11, the metal foil layer 12 and the nonmetal layer 13 of the first embodiment are used as a composite heat dissipation layer. Thus, the composite heat sink stack of the embodiment comprises a first composite heat sink layer 1 and a second composite heat sink layer 2. The backing adhesive layer of the second composite heat dissipation layer 2 is superposed on the nonmetallic layer of the first composite heat dissipation layer 1.
The steps for preparing the heat dissipating laminate described above are similar to the first embodiment, except that the previous steps are repeated after the first composite heat dissipating layer is completed.
Compared with the first embodiment, the heat dissipation laminated structure of the second embodiment increases the distance between the bottom layer (bottom end of the heat dissipation laminated structure) for receiving heat and the air interface (top end of the heat dissipation laminated structure) for dissipating heat due to the increase of the number of layers, thereby facilitating the rapid transfer of heat away from the heat generating device, improving the heat dissipation efficiency and protecting the peripheral devices of the heat generating device.
The metal foil layers of the first composite heat dissipation layer 1 and the second composite heat dissipation layer 2 may be the same or different. For example, the metal foil layer of the first composite heat dissipation layer 1 is copper foil, and the metal foil layer of the second composite heat dissipation layer 2 is aluminum foil.
Fig. 3 is a schematic structural view of a third embodiment of the heat dissipation lamination structure of the present invention. As shown in fig. 3, this embodiment is a further extension of the second embodiment. The heat dissipation lamination structure comprises more than two composite heat dissipation layers, namely a first composite heat dissipation layer 1, a second composite heat dissipation layer 2, … … and an Nth composite heat dissipation layer N. N is a natural number and not less than 2.
The method for preparing the heat dissipation lamination structure of the embodiment can also be repeatedly performed with reference to the second embodiment, so that the description is omitted.
Through applying a plurality of compound heat dissipation layers, can make the thickness of heat dissipation lamination structure increase by a large margin, can be like this with heat transfer to the place of keeping away from the heating device fast, improve radiating efficiency greatly, also can reduce the harm of heat to peripheral device minimum.
Fig. 4 is a schematic structural view of a fourth embodiment of the heat dissipation lamination structure of the present invention. This embodiment differs from the third embodiment in that the metal foil layers employed in adjacent composite heat sink layers are of different metals.
As can be seen from the third embodiment and the fourth embodiment, the metal foil layers in each of the multiple composite heat dissipation layers of the present invention may be the same or different. The selection of different metal foil layers can make the variation of the temperature gradient across the heat dissipation path special, whereby a targeted design can be made according to different device requirements to balance the heat dissipation efficiency with the degree of thermal damage to the peripheral devices.
Fig. 5 is a schematic structural view of a fifth embodiment of the heat dissipation lamination structure of the present invention. As shown in fig. 5, in order to further reduce the problem of high thermal resistance between the metal foil layer 12 and the non-metal layer 13 due to process or material compatibility, this embodiment adds a liquid metal layer 14 between the metal foil layer 12 and the non-metal layer 13. By liquid metal is meant herein a metal or alloy that is liquid at temperatures slightly above room temperature, including gallium-based binary alloys, gallium-based multi-component alloys, indium-based alloys, or bismuth-based alloys. Such as gallium indium alloy, gallium lead alloy, gallium indium tin alloy, indium bismuth copper alloy, and the like. Since the liquid metal layer 14 can have good compatibility with both the metal foil layer 12 and the non-metal layer 13 after melting (the melting point is between 40 and 150 degrees), the liquid metal layer and the non-metal layer can be closely contacted, the thermal resistance is reduced, and the heat dissipation efficiency is improved.
The liquid metal layer 14 of this embodiment can be formed by electroplating, powder spraying, deposition, etc. after the formation of the metal foil layer 12 structure, and then spraying a non-metallic material, such as graphene, onto the liquid metal layer 14. The thickness of the liquid metal layer 14 may be 1 μm to 30 μm.
It should be noted that the fifth embodiment of the present invention may be extended to a structure of two or more composite heat dissipation layers, that is, it may be applied to the second to fourth embodiments as a new implementation.
Fig. 6 is a schematic structural view of a sixth embodiment of the heat dissipation lamination structure of the present invention. Unlike the fifth embodiment, the liquid metal layer 14 of this embodiment is embedded on and flush with the surface of the metal foil layer 12 facing the non-metal layer 13. As shown in fig. 6, it can be considered that a depressed groove or pit is provided on the surface of the metal foil layer 12 facing the non-metal layer 13. A layer of liquid metal 14 fills the grooves or pits. The grooves or pits may be regularly arranged in a plane direction perpendicular to the heat transfer direction, or may be irregularly arranged, and the present invention is not limited thereto. However, for uniformity of heat conduction in all directions, the present invention is preferably arranged regularly.
The metal foil layer 12 having the liquid metal layer 14 embedded therein may be prepared by pressing or the like in advance, or the liquid metal layer 14 may be formed by electroplating, spraying or the like on the metal foil layer 12.
The sixth embodiment has an advantage over the fifth embodiment in that the liquid metal layer 14 is confined inside the heat dissipating structure and is not easily flown out to cause device damage.
Fig. 7 is a schematic structural view of a seventh embodiment of the heat dissipation lamination structure of the present invention. Unlike the sixth embodiment, the liquid metal layer 14 embedded in the metal foil layer 12 is not flush with the surface of the metal foil layer 12 facing the non-metal layer 13, but is embedded in the surface of the metal foil layer 12 facing the non-metal layer 13. This embodiment can use a smaller amount of liquid metal, reduce the cost of materials, and make the liquid metal layer 14 less likely to flow out or ooze out, and safer than the sixth embodiment.
Fig. 8 is a schematic structural view of an eighth embodiment of the heat dissipation lamination structure of the present invention. This embodiment is similar to the sixth and seventh embodiments, but does not have a liquid metal layer 14. Specifically, this embodiment is also provided with depressed grooves or dimples on the surface of the metal foil layer 12 facing the non-metal layer 13, and capillary structures are formed at the bottoms and sides of the dimples or grooves. The wicking structure may be formed by stamping, by forming the wicking structure such that non-metallic materials, such as graphene, have a larger contact surface after being sprayed onto the metal foil layer 12, and the contact of the two materials is also more dense, thereby effectively increasing thermal conductivity.
The heat dissipation laminated structure can be applied to various radiators, and the radiators adopting the heat dissipation laminated structure are all within the protection scope of the invention.
The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the invention thereto, but to limit the invention thereto, and any modifications, equivalents, improvements and equivalents thereof may be made without departing from the spirit and principles of the invention.