A heat dissipation gasket for an electrical component, its preparation method and application

Abstract

The present invention belongs to the technical field of electrical components. The present invention discloses a preparation method of a heat dissipation gasket for an electrical component, comprising: machining a grid on the surface of a substrate; then coating a liquid metal melted into a superheated state in the grid of the substrate, and obtaining a composite gasket through cooling and solidification; then wrapping a layer of high thermal conductivity metal foil with uniform pores around the composite gasket, and obtaining a heat dissipation gasket through rolling and flattening. The heat dissipation gasket prepared by this method has good thermal conductivity and anti-leakage performance, solves the problems of too strong fluidity and easy leakage of liquid metal in the heat dissipation application of actual chips, and realizes the balance between high-efficiency heat transfer and safety of liquid metal.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical components, and particularly relates to a heat dissipation gasket for electrical components, a preparation method thereof, and an application thereof. Background Art

[0002] In modern electronic products, such as laptops, tablets, mobile phones, smart watches, household appliances, etc., electronic components are indispensable. Among electronic components, the heat dissipation problem of chips such as GPUs and CPUs has always been a key factor affecting the performance and lifespan of electronic products. In the technical field of heat dissipation of electrical components, especially chips, traditional heat dissipation thermal interface materials, such as thermal grease, heat dissipation gaskets, etc., although they can provide a certain heat dissipation effect, in application scenarios with high power consumption and high heat flux density, their thermal conductivity still has limitations, so it is often difficult to meet the heat dissipation requirements of high-performance chips.

[0003] Liquid metal is an alloy with high thermal conductivity and good thermal expansion matching property, and it has gradually become an ideal thermal interface material. However, liquid metal often has problems such as too strong fluidity and easy leakage in practical applications, which limits its wide application in the field of heat dissipation of electronic components. Summary of the Invention

[0004] In view of the above technical problems, the present invention provides a heat dissipation gasket for electrical components, a preparation method thereof, and an application thereof. The heat dissipation gasket prepared by this method has good thermal conductivity and anti-leakage performance, solves the problems of too strong fluidity and easy leakage of liquid metal in the actual heat dissipation application of chips, and realizes the balance between high-efficiency heat transfer and safety of liquid metal. The heat dissipation gasket prepared by this method is suitable for the heat dissipation of chips of electrical components, and can extend the performance and service life of electronic products.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions:

[0006] In the first aspect, the present invention provides a preparation method of a heat dissipation gasket for electrical components, comprising the following steps:

[0007] S1. Uniformly process a grid on the surface of a substrate;

[0008] S2. Then fill the grid with liquid metal that has been melted into a superheated state, and obtain a composite gasket after cooling and solidification;

[0009] S3. Then wrap a layer of high thermal conductivity metal foil with uniform pores around the composite gasket, and obtain a heat dissipation gasket after rolling and leveling.

[0010] The present invention designs and processes grids with a specific depression depth on the upper and lower surfaces of a substrate. The grids do not penetrate the substrate but form a uniformly distributed grid structure on the upper and lower surfaces of the substrate layer. The grids in the grid structure on the upper and lower surfaces of the substrate are filled with a liquid metal with high thermal conductivity and low melting point. After cooling and solidification, a composite gasket is obtained. Then, a high-thermal-conductivity copper foil with uniform pores is wrapped around the periphery of the composite gasket. After rolling and flattening, a heat dissipation gasket is obtained. The grid structures provided on the upper and lower surfaces of the substrate can not only confine and impede the flow of the liquid metal in the molten state, thereby avoiding potential safety hazards caused by the overflow and leakage of the liquid metal, but also reduce the interfacial thermal resistance of the heat dissipation gasket. At the same time, the grids are filled with a liquid metal with good thermal conductivity, greatly reducing the thermal resistance of the heat dissipation gasket. Then, a high-thermal-conductivity metal foil with uniform pores is wrapped around the outer layer of the composite gasket, which can not only maximize the contact between the liquid metal and the electrical components for heat dissipation, but also further avoid the possibility of the overflow and leakage of the liquid metal, further improving the reliability of the electronic components and ensuring excellent heat dissipation efficiency of the electronic components.

[0011] In summary, under the synergistic effect of the high-thermal-conductivity substrate, the liquid metal with excellent thermal conductivity, the grid structure of the substrate, and the high-thermal-conductivity metal foil with uniform pores on the outer layer, a heat dissipation gasket with excellent thermal conductivity is obtained. It can reduce the thermal resistance to 0.05 °C·cm 2 / W, thereby improving the heat dissipation efficiency of the electronic components and prolonging the performance and service life of the electronic products.

[0012] Therefore, the heat dissipation gasket obtained by the preparation method of the heat dissipation gasket for electrical components of the present invention has good thermal conductivity and anti-leakage performance. Using this heat dissipation gasket for the chip heat dissipation of electrical components can solve the problems of excessive fluidity and easy leakage of liquid metal in the actual chip heat dissipation application, achieve the balance between the high-efficiency heat transfer and safety of the liquid metal, and prolong the performance and service life of the electronic products.

[0013] Preferably, in S1, an imprinting or etching process is used to uniformly process grids on the two surfaces of the substrate to form a uniformly distributed grid structure on the upper and lower surfaces of the substrate.

[0014] Preferably, the shape of the grid is: square, rhombus, circle or hexagon.

[0015] Preferably, the side length of each grid is 10 - 40 μm, the depth is 20 - 30 μm, and the spacing between the depression regions of each grid is 5 - 20 μm.

[0016] At the same side length or diameter, compared with circular or hexagonal grids, the square grid of the present invention has the largest surface area, can fill the most liquid metal, and has the best heat dissipation effect.

[0017] When the side length of the square grid is 10 - 40 μm, the depth is 20 - 30 μm, and the spacing between the sunken areas of the grid is 5 - 20 μm, it is possible to obtain a heat dissipation gasket with a relatively good heat dissipation effect and guaranteed quality without leaking liquid metal on the premise of a relatively large amount of liquid metal filled and a relatively good heat dissipation effect.

[0018] When the side length of the square grid > 40 μm, it will cause too much liquid metal filled in the heat dissipation gasket, and there is a risk of leakage; when the side length of the square grid < 10 μm, it will cause too little liquid metal filled in the gasket, and the heat dissipation effect is poor.

[0019] When the spacing between the sunken areas of the grid < 5 μm, it will cause too little liquid metal filled in the heat dissipation gasket, and the best heat dissipation effect cannot be achieved; when the spacing between the sunken areas of the grid > 20 μm, it will cause too much liquid metal filled in the heat dissipation gasket, and there is a risk of leakage.

[0020] When the depth of the grid < 20 μm, it will cause too little liquid metal filled in the heat dissipation gasket, and the best heat dissipation effect cannot be achieved; when the depth of the grid > 30 μm, it will cause too much liquid metal filled in the heat dissipation gasket, and there is a risk of leakage.

[0021] Preferably, the specific preparation method of step S2 includes:

[0022] First, uniformly coat the liquid metal melted into a superheated state in the grid on one surface of the base layer, and remove the excess liquid metal. After ensuring that the liquid metal is only filled in the reticular depression area, at room temperature of 25 °C, cool it with water, and after cooling and solidifying for 1 - 2 min, obtain a base material containing a first grid liquid metal layer;

[0023] Then, uniformly coat the liquid metal melted into a superheated state in the grid on the other surface of the base material containing the first grid liquid metal layer, and remove the excess liquid metal. After ensuring that the liquid metal is only filled in the reticular depression area, at room temperature of 25 °C, cool it with water for 1 - 2 min, and after cooling and solidifying, obtain a composite gasket containing a first grid liquid metal layer, a base material layer, and a second grid liquid metal layer;

[0024] Then, wrap a layer of high - thermal - conductivity metal foil with uniform pores around the composite gasket, and after repeating rolling 2 - 3 times under a rolling gap of 0.2 - 0.5 mm, obtain a uniform and flat heat dissipation gasket.

[0025] The heat dissipation gasket obtained by the preparation method of the present invention has good thermal conductivity and excellent anti - leakage performance.

[0026] The thickness of the high thermal conductivity metal foil used in the present invention is 5 μm, the pore diameter on the surface of the high thermal conductivity metal foil is 0.5 - 1 mm, and the porosity is 50% - 90%. When the porosity on the surface of the high thermal conductivity metal foil is too small (<50%), it will affect the heat dissipation performance of the heat dissipation gasket; when the porosity on the surface of the high thermal conductivity metal foil is too large, it cannot prevent the leakage of liquid metal. The high thermal conductivity metal foil is any one of copper foil, silver foil or aluminum foil. Among them, the size of the pores on the surface of the high thermal conductivity metal foil can be adjusted according to the heat dissipation requirements of different electrical components, and the size and distribution of the pores can be adjusted.

[0027] Preferably, the raw materials for preparing the liquid metal are heated at 60°C - 80°C for 20 - 30 min to obtain a molten and superheated state of liquid metal. Among them, the raw materials for preparing the liquid metal are composed of In-Sn-Bi eutectic alloy with a mass percentage of (45% - 50%):(30% - 33%):(15% - 20%).

[0028] The In-Sn-Bi eutectic alloy with the above ratio is heated at 60°C - 80°C for 20 - 30 min to be melted into a superheated state of liquid metal. This low melting point liquid metal is a good heat conducting material, which can greatly reduce the thermal resistance of the heat dissipation gasket and improve the heat dissipation efficiency of electronic components.

[0029] Preferably, the thickness of the base material is 200 - 300 μm; among them, the base material includes: indium foil, silver foil, titanium alloy foil or copper foil; the purity of the above base materials is ≥99.9%

[0030] In the second aspect, the present invention also provides a heat dissipation gasket for electrical components, which is prepared by using the preparation method of the heat dissipation gasket for the above electrical components.

[0031] The heat dissipation gasket of the present invention has good heat conduction performance and anti-leakage performance, can be used for the heat dissipation of the chips of electrical components, and can solve the problems such as too strong fluidity and easy leakage of liquid metal in the actual heat dissipation application of chips.

[0032] In the third aspect, the present invention also provides the preparation method of the heat dissipation gasket for the above electrical components or the heat dissipation gasket for the above electrical components for the heat dissipation of the chips of electrical components.

[0033] The heat conduction gasket of the present invention is applicable to the heat dissipation scenarios of various electronic devices, such as the heat dissipation of chips of smart phones, tablet computers, notebook computers, servers, etc. It has a wide range of applications and broad market application prospects. Description of the Drawings

[0034] Figure 1 It is the process flow of the preparation method of the heat dissipation gasket for the electrical components of the present invention;

[0035] Figure 2Schematic diagram of the composite gasket of the electrical component heat dissipation gasket of the present invention; wherein, 1 is the substrate layer, 2 is the liquid metal, 3 is the first grid liquid metal layer, and 4 is the second grid liquid metal layer;

[0036] Figure 3 Planar schematic diagram of the preparation method of the electrical component heat dissipation gasket of the present invention. Specific embodiments

[0037] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. The "upper", "lower", "left", and "right" defined in the present invention are limited to the views shown in the drawings of the specification of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of the present invention.

[0038] Liquid metal is an alloy with high thermal conductivity and good thermal expansion matching, and it has gradually become an ideal thermal interface material. However, in practical applications, liquid metal often has problems such as too strong fluidity and easy leakage of liquid metal, which limit its wide application in the field of heat dissipation of electronic components.

[0039] The present invention provides a method for preparing an electrical component heat dissipation gasket, including the following steps:

[0040] S1. Process a grid structure on the surface of the substrate

[0041] By imprinting or etching, grids are uniformly processed on the upper and lower surfaces of the substrate. The shape of the grids can be square, rhombus, circular or hexagonal. Among them, the specific dimensions of the grids are: the side length or diameter is 10-40 μm, the depth is 20-30 μm, and the spacing of the concave areas of each grid is 5-20 μm. Flexible high thermal conductivity metal substrate: indium foil, silver foil, titanium alloy foil or copper foil are used. Among them, the substrate thickness is 200-300 um, and the purity of the substrate ≥ 99.9%.

[0042] S2. Fill, coat, cool and solidify the liquid metal, and level it with a pressure roller

[0043] On one surface grid of the base layer, uniformly coat the liquid metal melted into a superheated state, and after removing the excess liquid metal, at room temperature, water-cool and solidify for 1-2 minutes to obtain a substrate containing the first grid liquid metal layer;

[0044] Then, melt the liquid metal into a superheated state and uniformly coat it in the grids on the other surface of the substrate containing the first grid liquid metal layer. After removing the excess liquid metal, at room temperature, water-cool and solidify for 1 - 2 minutes to obtain a composite gasket containing the first grid liquid metal layer, the substrate layer, and the second grid liquid metal layer;

[0045] Then, wrap a layer of high thermal conductivity metal foil with uniform pores around the composite gasket. After that, under a rolling gap of 0.2 - 0.5 mm, repeat rolling 2 - 3 times to obtain a uniform and flat heat dissipation gasket.

[0046] Among them, heat the raw materials for preparing the liquid metal at 60°C - 80°C for 20 - 30 minutes to obtain the liquid metal in a melted and superheated state; the raw materials for preparing the liquid metal are composed of In - Sn - Bi eutectic alloy with a mass percentage of (45% - 50%):(30% - 33%):(15% - 20%);

[0047] The thickness of the high thermal conductivity metal foil is 5 μm, the pore diameter on the surface of the high thermal conductivity metal foil is 0.5 - 1 mm, and the porosity is 50% - 90%. If the porosity is too small (<50%), it will affect the heat dissipation performance of the heat dissipation gasket; when the porosity is too large, there will be no effect of protecting the liquid metal from leakage.

[0048] The high thermal conductivity metal foil is any one of copper foil, silver foil, or aluminum foil. Among them, the size of the pores on the surface of the high thermal conductivity metal foil can be adjusted according to the heat dissipation requirements of different electrical components, and the size and distribution of the pores can be adjusted.

[0049] The heat dissipation gasket obtained by the above preparation method can be used for the chip heat dissipation of electrical components, which can significantly improve the heat dissipation efficiency, reduce the chip working temperature, and extend the service life of electrical components.

[0050] The following are specific examples for illustrating the preparation method and application effect of the present invention.

[0051] Example 1

[0052] The present invention provides a preparation method for a heat dissipation gasket of an electrical component; including:

[0053] S1. Process a grid structure on the surface of the substrate

[0054] Adopt an imprinting process to process square grids with a side length of 40 μm and a depth of 30 μm on the upper and lower surfaces of an indium foil with a thickness of 200 μm, and the spacing of the grid depression areas is 10 μm.

[0055] S2. Liquid metal coating, cooling and solidification, and rolling and flattening

[0056] Heat the In-Sn-Bi eutectic alloy with a mass percentage of 51%: 32.5%: 16.5% at 60 °C for 20 min to obtain a liquid metal melted to the superheated state; subsequently, use a heat-resistant (greater than 150 °C) brush to coat and fill the liquid metal melted to the superheated state into the grid of the indium foil substrate, and use a heat-resistant (greater than 150 °C) scraper to remove the excess liquid metal to ensure that the liquid metal is only filled in the grid depression area; then place it on a cooling table and cool and solidify it in water cooling at room temperature of 25 °C for 1 min to obtain a substrate containing a first grid liquid metal layer;

[0057] Then use a heat-resistant (greater than 150 °C) brush to coat the liquid metal melted to the superheated state onto the grid of the other surface of the substrate containing the first grid liquid metal layer, and use a heat-resistant (greater than 150 °C) scraper to remove the excess liquid metal to ensure that the liquid metal is only filled in the grid depression area; then place it on a cooling table and cool and solidify it in water cooling at room temperature of 25 °C for 2 min to obtain a composite gasket containing a first grid liquid metal layer, a substrate layer and a second grid liquid metal layer;

[0058] Then wrap a layer of high thermal conductivity copper foil with a thickness of 5 μm, a surface pore diameter of 1 mm and a porosity of 80% around the composite gasket, and after repeating the rolling 2 times at a rolling gap of 0.2 mm, a uniform and flat heat dissipation gasket is obtained.

[0059] From Figure 1 It can be seen the process flow of the preparation method of the heat dissipation gasket for electrical components of the present invention. From Figure 2 and Figure 3 It can be seen that the heat dissipation gasket of the present invention is composed of a first grid liquid metal layer, a substrate layer, a second grid liquid metal layer, and a high thermal conductivity copper foil coating layer with uniform pores. The grid structures on the upper and lower surfaces of the substrate can reduce the interface thermal resistance. At the same time, the low melting point liquid metal layer has good thermal conductivity, which greatly reduces the thermal resistance of the heat dissipation gasket. The high thermal conductivity copper foil coating layer can not only maximize the contact between the liquid metal and the electrical components for heat dissipation, but also further prevent the overflow and leakage of the liquid metal, further improving the reliability of the electronic components and ensuring excellent heat dissipation efficiency of the electronic components.

[0060] Example 2

[0061] The present invention provides a preparation method of a heat dissipation gasket for electrical components, including the following steps:

[0062] S1. Process a grid structure on the surface of the substrate

[0063] The upper and lower surfaces of a silver foil with a thickness of 200 μm and a purity ≥ 99.9% are processed by an embossing process to produce square grids with a side length of 30 μm and a depth of 30 μm, and the spacing of the recessed areas of each grid is 10 μm.

[0064] S2. Coating with liquid metal, cooling and solidifying, and leveling with a pressure roller

[0065] The In-Sn-Bi eutectic alloy with a mass percentage of 50%: 33%: 17% is heated at 70 °C for 25 min to obtain a liquid metal melted to a superheated state; subsequently, a heat-resistant (greater than 150 °C) brush is used to coat and fill the melted and superheated liquid metal into the grids of the silver foil substrate, and a heat-resistant (greater than 150 °C) scraper is used to remove the excess liquid metal to ensure that the liquid metal is only filled in the recessed areas of the grids; then it is placed on a cooling table and cooled and solidified for 2 min in water cooling at room temperature of 25 °C to obtain a substrate containing a first grid liquid metal layer.

[0066] Again, a heat-resistant (greater than 150 °C) brush is used to coat the melted and superheated liquid metal onto the grids on the other surface of the substrate containing the first grid liquid metal layer, and a heat-resistant (greater than 150 °C) scraper is used to remove the excess liquid metal to ensure that the liquid metal is only filled in the recessed areas of the grids; then it is placed on a cooling table and cooled and solidified for 2 min in water cooling at room temperature of 25 °C to obtain a composite gasket containing a first grid liquid metal layer, a substrate layer, and a second grid liquid metal layer.

[0067] Then, a high thermal conductivity copper foil with a thickness of 5 μm, a surface pore diameter of 1 mm, and a porosity of 80% is wrapped around the periphery of the composite gasket, and after repeating the rolling 3 times with a rolling gap of 0.3 mm, a uniform and flat heat dissipation gasket is obtained.

[0068] Example 3

[0069] The present invention provides a method for preparing a heat dissipation gasket for an electrical component, comprising the following steps:

[0070] S1. Processing a grid structure on the surface of the substrate

[0071] The upper and lower surfaces of an indium foil with a thickness of 200 μm are processed by an embossing process to produce square grids with a side length of 40 μm and a depth of 20 μm, and the spacing of the recessed areas of each grid is 10 μm.

[0072] S2. Coating with liquid metal, cooling and solidifying, and leveling with a pressure roller

[0073] Heat the In-Sn-Bi eutectic alloy with a mass percentage of 52%:33%:15% at 80 °C for 30 min to obtain a liquid metal melted to the superheated state; then use a heat-resistant (greater than 150 °C) brush to coat and fill the melted and superheated liquid metal into the grid on one surface of the indium foil substrate, and use a heat-resistant (greater than 150 °C) scraper to remove the excess liquid metal to ensure that the liquid metal is only filled in the grid depression area; then place it on a cooling table and cool and solidify it in water cooling at room temperature of 25 °C for 2 min to obtain a substrate containing a first grid liquid metal layer;

[0074] Then use a heat-resistant (greater than 150 °C) brush to coat the melted and superheated liquid metal onto the grid on the other surface of the substrate containing the first grid liquid metal layer, and use a heat-resistant (greater than 150 °C) scraper to remove the excess liquid metal to ensure that the liquid metal is only filled in the grid depression area; then place it on a cooling table and cool and solidify it in water cooling at room temperature of 25 °C for 2 min to obtain a composite gasket containing a first grid liquid metal layer, a substrate layer and a second grid liquid metal layer;

[0075] Then wrap a layer of high thermal conductivity copper foil with a thickness of 5 um, a surface pore diameter of 1 mm and a porosity of 80% around the composite gasket, and then repeat the rolling 3 times under a rolling gap of 0.5 mm to obtain a uniform and flat heat dissipation gasket.

[0076] The present invention also provides a heat dissipation gasket for electrical components, which is prepared by using the preparation method of the heat dissipation gasket for electrical components described above.

[0077] Comparative Example 1

[0078] In the preparation method of the heat dissipation gasket for electrical components of the present invention, the substrate in S1 is a smooth indium sheet without surface grid treatment, and the periphery of the composite gasket is not wrapped with a high thermal conductivity copper foil layer, and the remaining steps are the same as those in Example 1.

[0079] Comparative Example 2

[0080] In the preparation method of the heat dissipation gasket for electrical components of the present invention, the side length of the square grid in S1 is changed to 50 um, and the periphery of the composite gasket is not wrapped with a high thermal conductivity copper foil layer, and the remaining steps are the same as those in Example 1.

[0081] Comparative Example 3

[0082] In the preparation method of the heat dissipation gasket for electrical components of the present invention, the periphery of the composite gasket is not wrapped with a high thermal conductivity copper foil coating layer, and the remaining steps are the same as those in Example 1.

[0083] Application Example 1

[0084] Perform performance tests on the heat dissipation gaskets prepared in Examples 1-3 and Comparative Examples 1-3.

[0085] Specifically, the heat dissipation gaskets prepared in Examples 1-3 and Comparative Examples 1-3 were respectively placed on a thermal resistance meter to test the thermal resistance. Under the test conditions of 80 °C and 50 psi, the thermal resistance performance test was carried out according to the test standard ASTM D5470, and the thermal resistance instrument was Ruiling LW-9389; it was judged whether there was leakage by visual observation. The test results are shown in Table 1.

[0086] Table 1 Test Results

[0087]

[0088] As can be seen from Table 1, the thermal resistances of the heat dissipation gaskets prepared in Examples 1-3 of the present invention are 0.062 °C·cm² / W, 0.068 °C·cm² / W, and 0.052 °C·cm² / W respectively, and there is no leakage phenomenon. For Comparative Examples 1-3, there is a leakage phenomenon. In particular, although Comparative Example 1 has a low thermal resistance, the leakage of its liquid metal is serious. This shows that Examples 1-3 of the present invention have excellent anti-leakage and good heat dissipation effects.

[0089] In summary, the preparation method of the heat dissipation gasket for electrical components of the present invention designs a grid structure with a specific depression depth on the upper and lower surfaces of the substrate. This grid structure does not penetrate the substrate, and a liquid metal with high thermal conductivity is filled in the grid structure. After cooling and solidification, and coating with a leak-proof high thermal conductivity copper foil layer, and finally rolling and flattening, a heat dissipation gasket is obtained. This grid structure can not only confine and hinder the flow of liquid metal in the molten state, avoid the safety hazards caused by the overflow and leakage of liquid metal, and improve the reliability of electronic components; this grid structure can also reduce the interface thermal resistance of the heat dissipation gasket, and at the same time can cooperate with the liquid metal with good thermal conductivity to greatly reduce the thermal resistance of the heat dissipation gasket; under the leak-proof effect of the high thermal conductivity copper foil coating layer, the anti-leakage performance of the heat dissipation gasket is further improved, and its safety performance is enhanced. In summary, under the synergistic effect of the high thermal conductivity substrate, the liquid metal with excellent thermal conductivity, the grid structure of the substrate, and the high thermal conductivity copper foil with uniform pores, a heat dissipation gasket with excellent thermal conductivity effect is obtained, and the thermal resistance can be reduced to 0.05 °C*cm 2 / W. It can effectively solve the problems of strong fluidity and easy leakage of liquid metal in the actual chip heat dissipation application, achieve the balance between the high-efficiency heat transfer and safety of liquid metal, significantly improve the heat dissipation performance of electronic components, ensure the stable operation of electronic products, and extend the service life of electronic products.

[0090] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, or improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A preparation method of a heat dissipation gasket for an electrical component, characterized in that, It includes the following steps: S1: Uniformly process a grid on the surface of the substrate; S2: Fill the grid with liquid metal melted into a superheated state, and remove the excess liquid metal to ensure that the liquid metal is only filled in the concave areas of the grid. After cooling and solidifying, a composite gasket is obtained; S3: Then wrap a layer of high thermal conductivity metal foil with uniform pores around the composite gasket, and after rolling and flattening, a heat dissipation gasket is obtained; Among them, the side length of each grid is 10 - 40 μm, the depth is 20 - 30 μm, and the spacing of the concave areas of each grid is 5 - 20 μm; The thickness of the high thermal conductivity metal foil is 5 μm, the pore diameter on the surface of the high thermal conductivity metal foil is 0.1 - 1 μm, and the porosity is 50% - 90%.

2. The preparation method of the heat dissipation gasket for the electrical component according to claim 1, wherein, In S1, a grid is uniformly processed on both surfaces of the substrate by using an embossing or etching process.

3. The preparation method of the heat dissipation gasket for the electrical component according to claim 2, wherein, The shape of the grid is: square, rhombus, circle or hexagon.

4. The preparation method of the heat dissipation gasket for the electrical component according to claim 1, characterized in that, The specific preparation method of step S2 includes: Uniformly coat the liquid metal melted into a superheated state in the grid on one surface of the base layer, and remove the excess liquid metal to ensure that the liquid metal is only filled in the concave areas of the grid. Then, at room temperature, after water cooling and solidifying for 1 - 2 min, a substrate containing a first grid liquid metal layer is obtained; Uniformly coat the liquid metal melted into a superheated state in the grid on the other surface of the substrate containing the first grid liquid metal layer, and remove the excess liquid metal to ensure that the liquid metal is only filled in the concave areas of the grid. Then, at room temperature, after water cooling and solidifying for 1 - 2 min, a composite gasket containing a first grid liquid metal layer, a substrate layer and a second grid liquid metal layer is obtained; Then wrap a layer of high thermal conductivity metal foil with uniform pores around the composite gasket, and under a rolling gap of 0.2 - 0.5 mm, after repeated rolling 2 - 3 times, a uniformly flat heat dissipation gasket is obtained.

5. The preparation method of the heat dissipation gasket for an electrical component according to claim 4, wherein The raw materials for preparing the liquid metal are heated at 60°C - 80°C for 20 - 30 min to obtain liquid metal in a melted and superheated state; and / or The high thermal conductivity metal foil is any one of copper foil, silver foil or aluminum foil.

6. The preparation method of the heat dissipation gasket for the electrical component according to claim 4, characterized in that, The thickness of the substrate is 200 - 300 μm; the substrate includes: indium foil, silver foil, titanium alloy foil or copper foil; the purity of the substrate ≥ 99.9%.

7. The preparation method of the heat dissipation gasket of the electrical component according to claim 5, wherein, The raw materials for preparing the liquid metal are composed of an In - Sn - Bi eutectic alloy with a mass percentage of (45% - 50%):(30% - 33%):(15% - 20%).

8. A heat dissipation gasket for an electrical component, prepared by using the preparation method of the heat dissipation gasket for an electrical component according to any one of claims 1 - 7.

9. Using the preparation method of the heat dissipation gasket for an electrical component according to any one of claims 1 - 7 or the heat dissipation gasket for an electrical component according to claim 8 for heat dissipation of an electrical component.

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