Thermally conductive gasket

Abstract

The embodiment of the application provides a kind of heat-conducting gasket, it is related to heat-conducting interface material technical field.The heat-conducting gasket includes graphite layer, the graphite layer includes multiple graphite strips fixedly connected, multiple graphite strips are arranged along the first direction, the graphite strip has the first thermal conductivity in the thickness direction of the heat-conducting gasket, the graphite strip has the second thermal conductivity in the first direction, the first thermal conductivity is higher than the second thermal conductivity.The heat-conducting gasket is made of graphite, and the horizontal heat-conducting performance of graphite can be fully played by structure optimization, and the thermal conductivity of the heat-conducting gasket in its thickness direction is improved.

Description

Technical Field

[0001] This application relates to the field of thermal interface materials technology, specifically to a thermal pad. Background Technology

[0002] As the performance and computing power of terminal electronic devices become increasingly powerful, the heat dissipation problem of electronic components such as chips is becoming more and more prominent. Thermally conductive interface materials can be used to fill the gaps between the contact surfaces of electronic components and heat sinks, thereby improving the heat dissipation effect of electronic components.

[0003] Natural graphite sheets are excellent thermal conductors, possessing low thermal resistance, low specific gravity, and excellent processing properties such as thinness, flexibility, and ease of cutting. They can be laminated and compounded as needed. However, due to the inherent structure of graphite sheets, commercially available graphite sheet rolls have a high horizontal thermal conductivity but poor vertical thermal conductivity. Here, vertical direction refers to the thickness direction of the graphite sheet roll, while horizontal thermal conductivity refers to the thermal conductivity in a direction parallel to the surface of the graphite sheet roll (or perpendicular to the thickness direction of the graphite sheet roll).

[0004] In addition, graphite sheets are conductive, which limits their application in heat dissipation scenarios for electronic devices.

[0005] Therefore, how to fully utilize the high thermal conductivity of graphite sheets for thermal pads made of graphite is a technical problem that needs to be solved by those skilled in the art. Utility Model Content

[0006] The purpose of this application is to provide a thermally conductive pad based on graphite, which, through structural optimization, can fully utilize the horizontal thermal conductivity of graphite and improve the thermal conductivity of the thermally conductive pad in its thickness direction.

[0007] To address the aforementioned technical problems, this application provides a thermally conductive pad, which includes a graphite layer and a plurality of graphite strips fixedly connected together. The plurality of graphite strips are arranged along a first direction, and the graphite strips have a first thermal conductivity in the thickness direction of the thermally conductive pad and a second thermal conductivity in the first direction. The first thermal conductivity is higher than the second thermal conductivity.

[0008] In some possible implementations, the thermal pad includes an insulating layer that is stacked with the graphite layer.

[0009] In some possible implementations, the insulating layer is elastic.

[0010] In some possible implementations, the insulating layer comprises thermally conductive silicone.

[0011] In some possible implementations, the thermal conductivity of the thermally conductive silicone is 2.5-3.5 W / (m·K), and / or the hardness of the thermally conductive silicone is 30 Shore 00.

[0012] In some possible implementations, the insulating layer and the graphite layer are connected by an adhesive layer.

[0013] In some possible implementations, adjacent graphite strips are connected by an adhesive strip along the first direction.

[0014] In some possible implementations, the adhesive strip is made of one of epoxy resin, thermosetting resin, and acrylic resin.

[0015] In some possible implementations, the graphite strip has a dimension of d1 in the first direction, and the adhesive strip has a dimension of d2 in the first direction, where 1 < d1 / d2 < 3.34.

[0016] In some possible implementations, an edge-sealing adhesive layer is provided on the outer periphery of the graphite layer.

[0017] The thermal pad provided in this embodiment has a graphite layer, which includes multiple graphite strips arranged along a first direction. By utilizing the property that graphite has different thermal conductivity in different directions, the direction of the graphite strips with higher thermal conductivity is aligned with the thickness direction of the thermal pad, and the multiple graphite strips are arranged along the direction with lower thermal conductivity. This can make full use of the thermal conductivity characteristics of the graphite strips, so that the thermal pad has a high thermal conductivity in its thickness direction, which is beneficial to improving the heat dissipation efficiency of heat-generating devices. Attached Figure Description

[0018] Figure 1 This is a structural diagram of the thermal pad provided in one embodiment of this application;

[0019] Figure 2 for Figure 1 The front view of the thermal pad shown;

[0020] Figure 3 for Figure 2 Sectional view along the AA direction;

[0021] Figure 4 A structural diagram of the stacked components during the manufacturing process of the thermal pad provided in this application;

[0022] Figure 5 for Figure 4 Cross-sectional view along the BB direction;

[0023] Figure 6 for Figure 4 The diagram shows the structure of multiple cut pieces after the stacked parts are cut along the cutting line CC;

[0024] Figure 7 for Figure 6 A partial cross-sectional view of the shaped part formed after multiple cut parts are coated and scraped with glue.

[0025] Figure 8 for Figure 7 The molded part shown is the part after the heat insulation layer has been applied.

[0026] Explanation of reference numerals in the attached figures:

[0027] Thermal pad 100, graphite layer 110, graphite strip 1101, adhesive strip 1102, insulating layer 120, adhesive layer 130, edge binding adhesive layer 131;

[0028] Graphite sheet 201, adhesive 202;

[0029] Stacked part 1P, cut part 2P, shaped part 3P, formed part 4P. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] The ordinal numbers used in the embodiments of this application are for distinguishing different components with the same name and do not indicate a specific order or primary / secondary relationship. The term "multiple" in this application refers to two or more.

[0032] For ease of understanding and description, the embodiments of this application define three directions based on the thermal pad, namely the first direction x, the second direction y, and the third direction z. The third direction z is the thickness direction z of the thermal pad, and the first direction x and the second direction y are two directions in a plane perpendicular to the thickness direction z. The first direction x and the second direction y can be set perpendicularly.

[0033] Please refer to this as well. Figures 1 to 3 , Figure 1 This is a structural diagram of the thermal pad provided in one embodiment of this application. Figure 2 for Figure 1 The above is a front view of the thermal pad. Figure 3 for Figure 2 Sectional view along the AA direction.

[0034] This application provides a thermally conductive pad 100, which includes a graphite layer 110. The graphite layer 110 includes a plurality of graphite strips 1101 fixedly connected together. The plurality of graphite strips 1101 are arranged along a first direction x and extend along a second direction y. The graphite strips 1101 have a first thermal conductivity in the thickness direction z of the thermally conductive pad 100 and a second thermal conductivity in the first direction x. The first thermal conductivity is greater than the second thermal conductivity.

[0035] Using the above scheme, the graphite layer 110 of the thermal pad 100 includes multiple graphite strips 1101 arranged along the first direction x. Utilizing the property that graphite has different thermal conductivity in different directions, the direction of the graphite strips 1101 with higher thermal conductivity is aligned with the thickness direction z of the thermal pad 100, and the multiple graphite strips 1101 are arranged along the direction with lower thermal conductivity. This fully utilizes the thermal conductivity characteristics of the graphite strips 1101, giving the thermal pad 100 a high thermal conductivity in the thickness direction z. When dissipating heat from electronic devices or other heat-generating devices, the larger surface area of ​​the thermal pad 100 can contact the heat-generating device, and the heat generated by the heat-generating device can be quickly transferred to the thermal pad 100 in the thickness direction z, which is beneficial to improving the heat dissipation efficiency of the heat-generating device.

[0036] The graphite strip 1101 can be cut from graphite sheets. The graphite strip 1101 is parallel to the plane of the graphite sheet surface in the thickness direction z of the thermal pad 100. Therefore, the thermal conductivity of the thermal pad 100 in the thickness direction z is related to the horizontal thermal conductivity of the graphite sheet, which is the thermal conductivity parallel to its surface. Because the graphite sheet has a high horizontal thermal conductivity, the high horizontal thermal conductivity of the graphite sheet can be utilized to obtain a thermal pad 100 with a high thermal conductivity in the thickness direction z.

[0037] In some implementations, two adjacent graphite strips 1101 can be connected by an adhesive strip 1102 along the first direction x. Fixing the graphite strips 1101 by adhesive is highly reliable and easy to implement.

[0038] For example, the adhesive strip 1102 can be made of epoxy resin. Epoxy resin has advantages such as good adhesion, low shrinkage, and good heat resistance, which can ensure the stability of the graphite strip 1101 connection and the durability of the thermal pad 100.

[0039] For example, the adhesive strip 1102 can be made of thermosetting resin adhesive. Thermosetting resin adhesive has advantages such as high bonding strength and heat resistance, which can ensure the structural stability and durability of the thermal pad 100.

[0040] For example, the adhesive strip 1102 can also be made of acrylic resin. Acrylic resin has high strength and impact resistance, which can ensure the structural stability and durability of the thermal pad 100.

[0041] In actual operation, resin adhesive can be applied between two adjacent graphite strips 1101. After rolling and curing, the resin adhesive forms an adhesive strip 1102.

[0042] In some implementations, the graphite strip 1101 has a dimension of d1 in the first direction x, and the adhesive strip 1102 has a dimension of d2 in the first direction x, where 1 < d1 / d2 < 3.34. For example, d1 / d2 can be 1.1, 1.2, 1.3, 1.7, 1.8, 1.92, 2, 2.3, 2.45, 2.6, 2.8, 3, 3.1, 3.2, 3.3, etc. This ensures the strong connection of the graphite strip 1101 while reducing the thermal resistance loss caused by the adhesive strip 1102, thus improving the thermal conductivity of the thermal pad 100.

[0043] For example, the size d1 of the graphite strip 1101 in the first direction x can be 0.5-1mm, and the size d2 of the adhesive strip 1102 in the first direction x can be 0.3-0.4mm.

[0044] In some embodiments, the thermal pad 100 may further include an insulating layer 120, which is stacked with a graphite layer 110. In other words, the insulating layer 120 and the graphite layer 110 are stacked in the thickness direction z. Thus, the thermal pad 100 has single-sided insulation. When applied to heat dissipation scenarios such as electronic devices, the thermal pad 100 can be placed between the electronic device and the heat sink, increasing the heat transfer efficiency between the electronic device and the heat sink while also achieving insulation between the electronic device requiring heat dissipation and the heat sink.

[0045] In some implementations, when the thermal pad 100 is provided with an insulating layer 120, the insulating layer 120 may also be elastic. In this way, when the thermal pad 100 is placed between the heat-generating device and the heat sink, the elasticity of the insulating layer 120 can compensate for processing and assembly errors, ensuring close contact between the heat-generating device, the heat sink, and the thermal pad 100, thereby improving the heat dissipation effect on the heat-generating device. In addition, the elastic insulating layer 120 can also improve the problem of the graphite strip 1101's lack of pressure resistance, giving the thermal pad 100 a certain degree of resilience, which can improve the pressure resistance of the thermal pad 100 and help extend its service life.

[0046] In practice, the insulating layer 120 includes thermally conductive silicone. The thermally conductive silicone can ensure the thermal conductivity of the thermal pad 100, while also providing insulation and elasticity.

[0047] For example, the thermally conductive silicone can be selected with a thermal conductivity of 2.5-3.5 W / (m·K) to ensure the thermal conductivity of the thermal pad 100.

[0048] For example, thermally conductive silicone with a hardness of 30 Shore 00 can be selected to ensure the structural performance of the heating pad 100.

[0049] In some implementation examples, when the thermal pad 100 is provided with an insulating layer 120 including thermally conductive silicone, it can have a compression of 10-15%, which can effectively compensate for assembly errors of heat-generating devices, heat sinks, or processing errors of related assembly components.

[0050] In some implementations, the insulating layer 120 and the graphite layer 110 can be connected by an adhesive layer 130. This ensures the reliability and stability of the connection between the insulating layer 120 and the graphite layer 110, allowing the insulating layer 120 and the graphite layer 110 to be tightly bonded together, thus ensuring the quality of the thermal pad 100.

[0051] In practice, the adhesive layer 130 connecting the insulating layer 120 and the graphite layer 110 and the adhesive strip 1102 connecting the graphite strip 1101 can use the same adhesive. This helps to save costs and improves the reliability of the connection between the insulating layer 120 and the graphite layer 110.

[0052] In applications, the adhesive layer 130 may also include an edge-binding adhesive layer 131 located on the outer periphery of the graphite layer 110. This protects the graphite strip 1101 and prevents it from being worn.

[0053] In actual operation, the adhesive layer 130 and the edge-binding adhesive layer 131 can be formed in one process or in two processes.

[0054] The following is combined with Figures 4 to 8 This article introduces a manufacturing process for the thermal pad 100 described in the foregoing embodiments. Figure 4 This is a structural diagram of the stacked components during the manufacturing process of the thermal pad provided in this application. Figure 5 for Figure 4 Cross-sectional view along the BB direction. Figure 6 for Figure 4 The diagram shown depicts the structure of multiple cut pieces after the stacked components are cut along the cutting line CC. Figure 7 for Figure 6 The image shown is a partial cross-sectional view of the shaped part formed after multiple cut parts have been coated and scraped with glue. Figure 8 for Figure 7 The molded part shown is the part after the heat insulation layer has been applied.

[0055] For ease of understanding, Figures 4 to 8The first direction x, the second direction y, and the thickness direction z in the middle are... Figures 1 to 3 The standards are consistent, and they are all defined based on the finished thermal pad 100.

[0056] In this embodiment, the manufacturing process of the thermal pad 100 includes:

[0057] Create a stacked component 1P. (Example) Figure 4 and Figure 5 As shown, the stack 1P includes a plurality of graphite sheets stacked along a first direction x, with adjacent graphite sheets 201 fixed together by a coated adhesive 202.

[0058] In actual operation, prepare several graphite sheets 201 of the same size. The thickness of the graphite sheets 201 can be selected from 0.025-1mm, specifically 0.5-1mm graphite sheets 201, which helps to ensure processing stability and cost advantage.

[0059] Adhesive 202 is applied to the first graphite sheet 201, then the second graphite sheet 201 is aligned and placed, adhesive 202 is applied to the second graphite sheet 201, then the third graphite sheet 201 is aligned and placed, and so on, until the stacking height in the first direction x is close to the size of the thermal pad 100 to be prepared in the first direction x.

[0060] In practice, the coating thickness of adhesive 202 can be as thin as possible while ensuring the bonding effect. For example, the coating thickness of adhesive 202 can be 0.3-0.4mm.

[0061] Adhesive 202 can be selected from epoxy resin adhesive, thermosetting resin adhesive or acrylic resin adhesive, etc.

[0062] After the stacked component 1P is manufactured, it can be rolled to ensure the reliability of the connection between the graphite sheets 201. After rolling, the adhesive 202 that overflowed due to the rolling process can be removed.

[0063] The rolled stack 1P is baked and cured to ensure the connection stability between the graphite sheets 201.

[0064] The curing temperature and curing time can be determined based on the type of adhesive 202, coating thickness, etc. For example, the curing temperature can be 100-200℃, and the curing time can be 3-6 hours.

[0065] After curing, the result is as follows Figure 4 and Figure 5 The stacked component 1P is shown.

[0066] After the stacked component 1P is made, it is cut to obtain the cut component 2P. The cutting line of the stacked component 1P is parallel to the second direction y, and the cutting direction is parallel to the first direction x. That is, the cutting direction is consistent with the stacking direction of the stacked component 1P and perpendicular to the plane on which the surface of the graphite sheet 201 is located. Figure 4 The double-dotted line in the middle indicates the cutting line CC and the cutting direction.

[0067] When cutting the stacked component 1P, the cutting dimension in the third direction z is 1 / 2 to 2 / 3 of the thickness of the thermally conductive pad 100 to be prepared. The stacked component 1P can be cut into multiple cut components 2P. Figure 6 Eight cut pieces 2P are illustrated as an example.

[0068] The cut component 2P includes multiple graphite strips 1101 arranged along the first direction x. Adjacent graphite strips 1101 are fixedly connected by a cured adhesive 202, which forms an adhesive strip 1102. It can be understood that the cut component 2P is the graphite layer 110 of the thermal pad 100. The thickness direction of the graphite layer 110 is the third direction z, which is parallel to the plane containing the surface of the graphite sheet 201 before cutting (i.e., the plane constructed by the third direction z and the second direction y). Therefore, the graphite strips 1101 have a high thermal conductivity in the third direction z (i.e., the thickness direction of the thermal pad 100).

[0069] In practice, the cutting of stacked component 1P can be done by wire cutting, laser cutting, blade cutting, etc. The cutting method can be selected based on the stacking height of stacked component 1P, that is, the dimension of stacked component 1P in the first direction x.

[0070] After obtaining the cut-out part 2P, an insulating layer 120 can be formed on the cut-out part 2P to obtain a thermally conductive pad 100. For example, an adhesive 202 can be applied to one surface of the cut-out part 2P in the third direction z to form an adhesive layer 130, and then the insulating layer 120 can be stacked on the adhesive layer 130 to ensure the reliability of the connection between the insulating layer 120 and the cut-out part 2P (i.e., the graphite layer 110). Here, the adhesive 202 applied to the surface of the cut-out part 2P is the same type of adhesive as the adhesive 202 applied to the surface of the graphite sheet 201 when manufacturing the stacked part 1P, and the same reference numerals are used for illustration. In other embodiments, the adhesive forming the adhesive layer 130 and the adhesive connecting the graphite sheet 201 can be different types of adhesives.

[0071] In practice, multiple cut pieces 2P can be arranged at intervals along the first direction x, such as... Figure 6 As shown, adhesive 202 is applied to the surfaces of multiple cut pieces 2P simultaneously to form an adhesive layer 130, and an insulating layer 120 is subsequently applied to the adhesive layer 130. This simplifies the processing procedure.

[0072] In practice, a workbench can be set up with a groove on its surface. The dimension of this groove in the second direction y is close to the dimension of the cut piece 2P in the second direction y. The depth of the groove can be consistent with the thickness of the thermally conductive pad 100 to be prepared. Multiple cut pieces 2P are laid in the groove along the first direction x. Positioning marks can be set in the groove to ensure that the spacing between adjacent cut pieces 2P is consistent. The spacing between adjacent cut pieces 2P can be set to 1-2 mm.

[0073] After laying multiple cut pieces 2P within the groove, adhesive 202 is applied to the cut pieces 2P. The applied adhesive 202 fills the gaps between adjacent cut pieces 2P, and after curing, it forms an edge-sealing adhesive layer 131. The coating thickness of adhesive 202 can be determined as needed, for example, 0.5-1 mm. After applying adhesive 202, a set time can be allowed to stand to ensure that the adhesive 202 and the cut pieces 2P can fully bond. The set time can be determined as needed, for example, 60 minutes.

[0074] After applying adhesive 202 to multiple cut pieces 2P and allowing them to stand for a set time, the cut pieces 2P coated with adhesive 202 in the grooves can be shaped. For example, a scraper can be used for shaping to control the thickness of the adhesive 202 applied to the surface of the cut pieces 2P. After shaping, a shaped piece 3P is obtained, such as... Figure 7 As shown, Figure 7 A cross-sectional view of a partial shaping component 3P is shown. Since multiple cutting components 2P operate simultaneously within the groove, the shaping component 3P includes multiple cutting components 2P. The adhesive 202 applied to the surface of the cutting components 2P forms an adhesive layer 130 of the thermally conductive pad 100 after subsequent curing. The adhesive 202 filling the spaces between the cutting components 2P can form an edge-binding adhesive layer 131 of the thermally conductive pad 100 after subsequent curing.

[0075] After the shaped part 3P is made, thermally conductive silicone can be made and injected into the groove of the worktable to fill the remaining space in the groove depth direction, that is, the remaining space in the third direction z. After that, it can be shaped by roller pressing and then baked to cure, so as to ensure the stability and reliability of the connection between the thermally conductive silicone and the cut part 2P.

[0076] After baking and curing, the molded part 4P is obtained, such as Figure 8 As shown. The molded part 4P includes multiple cut parts 2P. Figure 8 The diagram illustrates the structure of the molded part 4P with the insulation layer 120 simultaneously applied to eight cut parts 2P. In practical applications, the molded part 4P can be cut according to usage requirements to obtain a thermal pad 100 of the required size.

[0077] In addition to the above manufacturing method, the thermal pad 100 can also be manufactured in other ways. For example, the graphite sheet 201 can be cut into multiple graphite strips 1101, and then the multiple graphite strips 1101 can be fixed by applying adhesive 202.

[0078] In one application example, a thermally conductive pad 100 made of graphite sheet 201 with a horizontal thermal conductivity of 1200 W / (m·K) can achieve a thermal conductivity of 600-700 W / (m·K) in the thickness direction z, which makes full use of the high thermal conductivity of graphite sheet 201. The processing technology of thermally conductive pad 100 is simple and helps to reduce costs.

[0079] The above are merely preferred embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A thermally conductive pad, characterized in that, The thermal pad (100) includes a graphite layer (110), the graphite layer (110) includes a plurality of graphite strips (1101) fixedly connected, the plurality of graphite strips (1101) are arranged along a first direction, the graphite strips (1101) have a first thermal conductivity in the thickness direction of the thermal pad (100), the graphite strips (1101) have a second thermal conductivity in the first direction, and the first thermal conductivity is higher than the second thermal conductivity.

2. The thermally conductive pad according to claim 1, characterized in that, The thermal pad (100) includes an insulating layer (120) which is stacked with the graphite layer (110).

3. The thermally conductive pad according to claim 2, characterized in that, The insulating layer (120) is elastic.

4. The thermally conductive pad according to claim 2, characterized in that, The insulating layer (120) comprises thermally conductive silicone.

5. The thermally conductive pad according to claim 4, characterized in that, The thermal conductivity of the thermally conductive silicone is 2.5-3.5 W / (m·K), and / or the hardness of the thermally conductive silicone is 30 Shore 00.

6. The thermally conductive pad according to claim 2, characterized in that, The insulating layer (120) and the graphite layer (110) are connected by an adhesive layer (130).

7. The thermally conductive pad according to any one of claims 1-6, characterized in that, Along the first direction, two adjacent graphite strips (1101) are connected by an adhesive strip (1102).

8. The thermally conductive pad according to claim 7, characterized in that, The adhesive strip (1102) is made of one of epoxy resin, thermosetting resin, and acrylic resin.

9. The thermally conductive pad according to claim 7, characterized in that, The graphite strip (1101) has a dimension of d1 in the first direction, and the adhesive strip (1102) has a dimension of d2 in the first direction, where 1 < d1 / d2 < 3.

34.

10. The thermally conductive pad according to any one of claims 1-6, characterized in that, An edge-sealing adhesive layer (131) is provided on the outer periphery of the graphite layer (110).

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