A foam indium heat-conducting gasket, its preparation method and application

Abstract

The application discloses a kind of foam indium heat-conducting gaskets and preparation method and application thereof, the foam indium heat-conducting gasket includes the following mass fraction of raw materials: pure indium ingot 100 parts;Tackifier 1-2 parts;Stabilizer 2-10 parts;Foaming agent 2-10 parts;Wherein, the purity of the pure indium ingot is greater than 99.9%.The above-mentioned raw materials are mixed according to the preset mass fraction, and the foam indium heat-conducting gasket is obtained by chemical foaming method.Compared with traditional foam metal material, the foam indium heat-conducting gasket prepared by the application has good ductility and flexibility, which can effectively reduce the interface contact gap and reduce the interface thermal resistance after being pressed.Furthermore, when the working temperature of electronic devices changes, the material can effectively compensate the thermal expansion mismatch phenomenon between the two mating surfaces, thereby improving the actual heat conduction effect of the foam indium heat-conducting gasket at high temperature, and further improving the reliability of electronic devices.

Description

Technical Field

[0001] This invention belongs to the field of thermal conductive materials technology, and particularly relates to a foamed indium thermal conductive pad, its preparation method and application. Background Technology

[0002] For electronic devices, especially chips, integration, miniaturization, and high power density are the hot topics and directions of development. According to Moore's Law, the number of components that can be accommodated on an integrated circuit doubles every 18 months; and with the increasing integration of electronic devices, the heat generated also increases significantly. Studies show that an increase in the junction temperature of heat-generating elements in electronic devices causes changes in output power, forward voltage, and mean time between failures (MTBF). For example, when the junction temperature of heat-generating elements exceeds the operating temperature of the electronic device, every 1°C increase will lead to a 4% decrease in the reliability of the electronic device. Therefore, how to effectively and promptly transfer the heat generated by high-power and high-density electronic devices to heat dissipation components and dissipate it into the air to achieve good thermal management is receiving increasing attention and importance from researchers.

[0003] For thermal management of electronic devices, the efficiency of heat transfer from the electronic device to the heat sink is the lowest, representing the bottleneck in the entire heat transfer process. This bottleneck is mainly due to the incomplete contact between the electronic device and the heat sink surface. The surfaces of the electronic device and the heat sink are not ideal planes but have a certain degree of roughness, thus the contact between them is actually a point contact. The air present at the contact point severely hinders heat transfer from the electronic device, leading to a significant increase in interfacial thermal resistance. In addition, the difference in the coefficients of thermal expansion between the electronic device and the heat sink causes uneven deformation between the materials when the temperature changes. These deformations inevitably lead to gaps between the electronic device surface and the heat sink, further severely reducing thermal conductivity.

[0004] To address these issues, researchers have attempted to use flexible elastomer interface materials or metal materials with high thermal conductivity as heat sinks to improve heat transfer. For example, CN 118388964 A discloses a thermally conductive pad and its preparation method, using silicone gel and methyl vinyl silicone as the matrix. The high flexibility of the matrix during pressing closes interfacial gaps to reduce interfacial contact thermal resistance. Simultaneously, a high proportion of thermally conductive filler is added to the matrix to improve the overall thermal conductivity of the pad. However, due to the poor thermal conductivity of elastomers, even when the added thermally conductive filler forms a thermally conductive path, it remains a point contact, resulting in a low thermal conductivity that cannot meet the actual heat dissipation requirements of high-performance integrated circuits. CN108109975 A discloses a high thermal conductivity heat sink with a three-dimensional foamed metal skeleton and its preparation method. It uses foamed copper as the skeleton material, achieving effective heat transfer through the high thermal conductivity of the metal. Simultaneously, high thermal conductivity materials are composited inside and / or on the surface, utilizing the three-dimensional structure of the foamed copper to enhance thermal conductivity. Unfortunately, there is a problem of poor interfacial contact between high thermal conductivity materials and copper foam. At the same time, it should be noted that as electronic devices operate, their temperature will also rise. The temperature change will cause thermal deformation between the copper foam and the surface material of the electronic device. Due to the different types of materials, their coefficients of thermal expansion will also differ. This difference will cause uneven deformation at the interface and create interfacial gaps. Since copper foam is relatively rigid, it is difficult to fill these gaps. Therefore, as the operating temperature rises, the actual thermal conductivity of copper foam heat sinks tends to decrease. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, embodiments of the present invention provide an indium foam thermally conductive pad, its preparation method, and its application. The indium foam thermally conductive pad not only possesses the high thermal conductivity of foam metal materials but also exhibits good flexibility, thus effectively reducing the interfacial contact thermal resistance and improving the thermal conductivity of the indium foam thermally conductive pad.

[0006] According to a first aspect of the present invention, a foamed indium thermally conductive pad is provided, the foamed indium thermal pad comprising the following raw materials in parts by weight: 100 parts of pure indium ingot; 1-2 parts of tackifier; 2-10 parts of stabilizer; and 2-10 parts of foaming agent; wherein the purity of the pure indium ingot is greater than 99.9%.

[0007] Optionally, the indium foam thermally conductive pad further includes: 0-5 parts of foaming agent; preferably, the foaming agent is 0.5-4 parts.

[0008] Optionally, the tackifier is selected from one or more of metallic calcium particles and alumina powder; the stabilizer is selected from one or more of alumina, silicon carbide, and metallic magnesium; preferably, the stabilizer is metallic magnesium; the foaming agent is selected from any one or more of azodicarbonamide, N,N-dinitrospentylmethyltetramine, diisopropyl azodicarbonate, and 4,4'-oxodibenzenesulfonyl hydrazine.

[0009] Optionally, the foaming agent is selected from one or more of zinc oxide, zinc stearate, stearic acid, lead stearate, cadmium oxide, and sodium bicarbonate.

[0010] According to a second aspect of the present invention, a method for preparing an indium foam thermally conductive pad is also provided. The method includes: mixing the pure indium ingot, a tackifier, a stabilizer, a foaming agent, and / or the foaming aid in a predetermined mass ratio, and then preparing the indium foam thermally conductive pad by a chemical foaming method.

[0011] Preferably, the preparation method includes: adding a thickener and a stabilizer to the indium melt formed from the pure indium ingot, and stirring thoroughly to obtain an indium melt mixture; adding a foaming agent and / or a foaming aid to the indium melt mixture at a first preset temperature, and stirring thoroughly to obtain a foamed indium melt mixture; wherein the first preset temperature is greater than the melting point of the pure indium ingot; and molding the foamed indium melt mixture and cutting it according to preset requirements to obtain a foamed indium thermal conductive pad.

[0012] Preferably, the step of adding a thickener and a stabilizer to the indium melt formed from the pure indium ingot and stirring thoroughly to obtain an indium melt mixture includes: heating the pure indium ingot to 170-180°C and holding it at that temperature for 20-30 minutes to obtain an indium melt; adding a thickener and a stabilizer to the indium melt and stirring thoroughly at a stirring speed of 1000-1500 r / min to generate an indium melt mixture.

[0013] Preferably, the step of adding a foaming agent and / or a foaming aid to the indium melt mixture at a first preset temperature and stirring thoroughly to obtain a foamed indium melt mixture includes: heating the indium melt mixture to 190-220°C; adding a foaming agent and / or a foaming aid to the heated indium melt mixture and stirring thoroughly to obtain a foamed indium melt mixture.

[0014] Preferably, the step of molding the foamed indium melt mixture and then cutting it according to preset requirements to obtain the foamed indium thermal conductive pad includes: injecting the foamed indium melt mixture into a mold and holding it at 190-220 degrees Celsius for 2-5 minutes; then cooling it until solidification and removing the foamed indium from the mold at 60-70 degrees Celsius; and after the foamed indium has cooled to room temperature, cutting it according to preset dimensions to obtain the foamed indium thermal conductive pad.

[0015] According to a third aspect of the present invention, an application of an indium foam thermally conductive pad in an electronic device is also provided, wherein the indium foam is adhered to the surface of the electronic device for transferring heat generated by the electronic device to a heat sink.

[0016] This invention provides a foamed indium thermally conductive pad, its preparation method, and its application. The foamed indium thermally conductive pad comprises the following raw materials in parts by weight: 100 parts pure indium ingot; 1-2 parts tackifier; 2-10 parts stabilizer; and 2-10 parts foaming agent; wherein the purity of the pure indium ingot is greater than 99.9%. The above raw materials are mixed in predetermined parts by weight and then the foamed indium thermally conductive pad is obtained through a chemical foaming method. Compared with traditional foamed metal materials (such as foamed copper and foamed aluminum), the foamed indium thermally conductive pad prepared by this invention has good ductility and flexibility. It can effectively reduce interfacial contact gaps and lower interfacial thermal resistance under pressure; and it can effectively compensate for the thermal expansion mismatch between two mating surfaces when uneven thermal deformation occurs between materials due to temperature changes in electronic devices. This improves the actual thermal conductivity of the foamed indium thermally conductive pad at high temperatures, thereby improving the reliability of electronic devices. Attached Figure Description

[0017] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0018] Figure 1 This is a schematic diagram of the process for preparing indium foam thermally conductive pads according to an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0020] Currently, for thermal management of electronic devices, the transfer of heat from the electronic device to the heat sink is the bottleneck in the entire heat conduction process. Due to surface roughness, ideal surface contact between the electronic device and the heat sink surface is often difficult to achieve, resulting in point contact in the form of synapses. This inevitably leads to significant interfacial voids. These voids are filled with air, whose thermal conductivity is only 0.02 W / (m·K), severely hindering heat transfer. Therefore, even if the thermal interface material has a high thermal conductivity, good heat transfer is still difficult when the interfacial voids are large. In addition, the different coefficients of thermal expansion between the electronic device and the heat sink should also be considered. Even if the electronic device and heat sink are well-fitted during installation and the interfacial gap is minimized, the temperature inevitably rises when the electronic device is in operation. This temperature rise will cause volumetric thermal response in the electronic device material itself. Due to the different interfacial materials, the resulting coefficients of thermal expansion between the electronic device and the heat sink will lead to different volumetric thermal response values. This will inevitably cause uneven deformation of the thermal interface, resulting in new interfacial voids and affecting heat transfer.

[0021] A foamed indium thermally conductive pad comprises the following raw materials in parts by weight: 100 parts pure indium ingot; 1-2 parts tackifier; 2-10 parts stabilizer; 2-10 parts foaming agent; and 0-5 parts foaming aid; wherein the purity of the pure indium ingot is greater than 99.9%.

[0022] The foamed indium thermal conductive pad is prepared by mixing the pure indium ingot, tackifier, stabilizer, foaming agent, and / or foaming aid in a predetermined mass ratio using a chemical foaming method.

[0023] Here, no specific implementation process of the chemical foaming method is limited, as long as it can produce foamed indium thermal conductive pads.

[0024] In this embodiment, adding an appropriate amount of tackifier to the indium melt prepared from pure indium ingot can improve the adhesion and bonding strength of the finished foamed indium thermal conductive pad; adding an appropriate amount of stabilizer can improve the thermal and chemical stability of the foamed indium thermal conductive pad; adding an appropriate amount of foaming agent and / or foaming aid can form tiny bubbles in the foamed indium thermal conductive pad. These bubbles not only help increase the overall thermal conductivity of the foamed indium thermal conductive pad (e.g., the foamed structure can improve thermal conductivity efficiency because the presence of bubbles can promote heat diffusion and reduce thermal resistance), but also reduce the weight of the thermal conductive pad, reduce the cost of the thermal conductive pad, and increase the shock absorption performance of the thermal conductive pad.

[0025] In order to improve the flexibility and thermal conductivity of the foamed indium thermally conductive pad, in a preferred embodiment of this example, the tackifier is selected from one or more of metallic calcium particles and alumina powder; the stabilizer is selected from one or more of alumina, silicon carbide, and metallic magnesium; and the foaming agent is selected from any one or more of azodicarbonamide, N,N-dinitrospentylmethyltetramine, diisopropyl azodicarbonate, and 4,4'-oxodibenzenesulfonyl hydrazine.

[0026] In a more preferred embodiment of this example, the stabilizer is magnesium metal; this is because magnesium metal can reduce the surface tension of the indium melt, thereby inhibiting the rupture of bubble walls, merging of bubbles, and collapse of bubbles in the indium melt; thus improving the overall thermal conductivity of the foamed indium thermal pad and reducing the weight of the foamed indium thermal pad.

[0027] In another preferred embodiment of this invention, the foaming agent is selected from one or more of zinc oxide, zinc stearate, stearic acid, lead stearate, cadmium oxide, and sodium bicarbonate. The foaming agent reduces the surface tension of the indium melt, promotes the formation of bubbles within the indium melt, thereby contributing to the formation of a uniform foam structure during the manufacturing process of the foamed indium thermally conductive pad. This improves the foaming efficiency of the indium melt, and consequently enhances the overall thermal conductivity and flexibility of the foamed indium thermally conductive pad.

[0028] Compared to traditional polymer elastomer thermal pads, the indium foam thermal pad prepared in this embodiment not only has good flexibility but also a high thermal conductivity. Furthermore, the metallic characteristics of the indium foam thermal pad can overcome the problems of aging and failure associated with traditional polymer elastomer thermal pads.

[0029] like Figure 1 The diagram shown is a schematic flowchart of the preparation of indium foam thermally conductive pads according to an embodiment of the present invention.

[0030] A method for preparing an indium foam thermally conductive pad includes at least the following steps:

[0031] S101, Add a thickener and a stabilizer to the indium melt formed from pure indium ingots, and stir thoroughly to obtain an indium melt mixture;

[0032] S102, add a foaming agent and / or a foaming aid to the indium melt mixture at a first preset temperature, and stir thoroughly to obtain a foamed indium melt mixture; wherein, the first preset temperature is greater than the melting point of pure indium ingot;

[0033] S103, after the foamed indium melt mixture is injection molded, it is cut according to the preset requirements to obtain foamed indium thermal conductive pads.

[0034] Specifically, the pure indium ingot is heated to 170-180°C and held at that temperature for 20-30 minutes to obtain indium melt. A thickener and stabilizer are added to the indium melt, and the mixture is stirred at a paddle speed of 1000-1500 r / min for 10-20 minutes to generate an indium melt mixture. The indium melt mixture is heated to 190-220°C. A foaming agent and / or a foaming aid are added to the heated indium melt mixture, and the mixture is stirred with a paddle for 2-4 minutes until homogeneous to obtain a foamed indium melt mixture. The foamed indium melt mixture is poured into a mold and held at 190-220°C for 2-5 minutes. It is then cooled to solidification and removed from the mold at 60-70°C. After the foamed indium cools to room temperature, it is cut to a preset size to obtain a foamed indium thermally conductive pad.

[0035] Here, the solidified indium foam is removed from the mold at 60-70°C. This is mainly because indium is very reactive and an indium oxide layer is easily formed on its surface. Removing it from the mold at a suitable temperature and placing it in the air allows an oxide film to form on the surface of the indium foam, thereby reducing the fluidity of the indium foam and preventing leakage of the indium melt.

[0036] Compared with existing technologies that use metal hydrides as foaming agents, this embodiment innovatively uses a chemical foaming method to prepare indium foam. This preparation method not only has the advantages of low energy consumption and easy control of foaming temperature, but also fills the gap in existing technologies for preparing indium foam from metallic indium.

[0037] In the following examples, the mass percentages are all obtained with reference to the mass of indium melt. For example, 1% of metallic calcium particles is used to indicate that the mass of metallic calcium particles is 1% of the mass of indium melt.

[0038] Example 1

[0039] A foamed indium thermally conductive pad comprises the following raw materials in parts by weight: 100 parts pure indium ingot; 1 part metallic calcium particles; 3 parts metallic magnesium; 4 parts 4,4'-oxodibenzenesulfonyl hydrazine; and 0.5 parts stearic acid.

[0040] The preparation method of the above-mentioned indium foam thermal conductive pad includes the following steps:

[0041] S1, Heat pure indium ingot to 175°C, melt it completely, and let it stand for 20 minutes to obtain indium melt;

[0042] S2, add 1% by mass of metallic calcium particles and 3% by mass of metallic magnesium to the indium melt, and stir with a paddle at 1200 r / min for 15 minutes to obtain an indium melt mixture;

[0043] S3, after adjusting the temperature of the indium melt mixture to 200℃, add 0.5% stearic acid and 4%,4'-oxodibenzenesulfonyl hydrazine by mass percentage to the indium melt mixture; and stir evenly with a stirring paddle to obtain a foamed indium melt mixture;

[0044] S4. Inject the foamed indium melt mixture into the mold and keep it at 200°C for 3 minutes. Then cool it until solidification and remove the foamed indium from the mold at 60-70°C. After it cools to room temperature, cut it into 10cm*10cm thermal conductive sheets with a thickness of 0.3mm to obtain foamed indium thermal conductive pads.

[0045] Example 2

[0046] A foamed indium thermally conductive pad comprises the following raw materials in parts by weight: 100 parts pure indium ingot; 1 part metallic calcium particles; 3 parts metallic magnesium; 4 parts diisopropyl azodicarbonate; and 0.5 parts stearic acid.

[0047] The preparation method of the above-mentioned indium foam thermal conductive pad includes the following steps:

[0048] S1, Heat pure indium ingot to 175°C, melt it completely, and let it stand for 20 minutes to obtain indium melt;

[0049] S2, add 1% by mass of metallic calcium particles and 3% by mass of metallic magnesium to the indium melt, and stir with a paddle at 1200 r / min for 15 minutes to obtain an indium melt mixture;

[0050] S3, after adjusting the temperature of the indium melt mixture to 190°C, add 0.5% stearic acid and 4% diisopropyl azodicarbonate by mass to the indium melt mixture; and stir evenly with a stirring paddle to obtain a foamed indium melt mixture;

[0051] S4. Inject the foamed indium melt mixture into the mold and keep it at 190°C for 3 minutes. Then cool it until solidification and remove the foamed indium from the mold at 60-70°C. After it cools to room temperature, cut it into 10cm*10cm thermal conductive sheets with a thickness of 0.3mm to obtain foamed indium thermal conductive pads.

[0052] Example 3

[0053] A foamed indium thermally conductive pad comprises the following raw materials in parts by weight: 100 parts pure indium ingot; 1 part metallic calcium particles; 3 parts metallic magnesium; 3 parts N,N-dinitrospentylmethyltetramine; and 0.5 parts stearic acid.

[0054] The preparation method of the above-mentioned indium foam thermal conductive pad includes the following steps:

[0055] S1, Heat pure indium ingot to 175°C, melt it completely, and let it stand for 20 minutes to obtain indium melt;

[0056] S2, add 1% by mass of metallic calcium particles and 3% by mass of metallic magnesium to the indium melt, and stir with a paddle at 1200 r / min for 15 minutes to obtain an indium melt mixture;

[0057] S3. After adjusting the temperature of the indium melt mixture to 220°C, add 0.5% stearic acid and 3% N,N-dinitrospentylmethyltetramine by mass to the indium melt mixture; and stir evenly with a stirring paddle to obtain a foamed indium melt mixture.

[0058] S4. Inject the foamed indium melt mixture into the mold and keep it at 220°C for 3 minutes. Then cool it until solidification and remove the foamed indium from the mold at 60-70°C. After it cools to room temperature, cut it into 10cm*10cm thermal conductive sheets with a thickness of 0.3mm to obtain foamed indium thermal conductive pads.

[0059] Comparative Example 1

[0060] Commercially available copper foam with a porosity >90% was selected and cut into 10cm*10cm pieces with a thickness of 0.3mm.

[0061] Performance testing

[0062] The performance of the thermal pads provided in the embodiments and comparative examples was tested using the following methods:

[0063] Thermal conductivity: tested according to ASTM D5470 international standard;

[0064] Elastic modulus test: Tested according to the national standard GB / T 22315-2008.

[0065] The test results are shown in Table 1:

[0066] Table 1 Performance parameters of thermal pads for comparative examples and embodiments

[0067] sample Thermal conductivity (W / (m·K)) Elastic modulus (E / GPa) Comparative Example 9.0 84.0 Example 1 51.7 6.4 Example 2 43.9 6.9 Example 3 48.8 5.7

[0068] Test results show that, compared with the copper foam thermal pad prepared by the conventional electrodeposition method in Comparative Example 1, the indium foam thermal pad prepared by the chemical foaming method in this embodiment not only has a higher thermal conductivity, but also a significantly reduced elastic modulus. The low elastic modulus brings higher flexibility to the indium foam thermal pad, thereby improving its flexibility.

[0069] In existing technologies, when electronic device materials undergo temperature response, uneven deformation at the electronic device interface due to differences in thermal expansion coefficients creates interfacial voids. These voids increase thermal resistance, thereby reducing the actual thermal conductivity between the electronic device and the heat sink. The foam thermally conductive pad of this application, with its excellent flexibility, can reduce the interfacial voids caused by electronic device interface deformation, thus improving the thermal conductivity between the electronic device and the heat sink.

[0070] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0071] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0072] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

[0073] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0074] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0075] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A foam indium heat conducting gasket, characterized by, The raw materials include the following parts by weight: 100 parts of pure indium ingots; 1-2 parts of tackifier; Stabilizer 2-10 parts; 2-10 parts of foaming agent; 0-5 parts of foaming agent; The purity of the indium ingot is greater than 99.9%. The thickener is selected from one or more of metallic calcium particles and alumina powder; The stabilizer is selected from one or more of alumina, silicon carbide, and metallic magnesium; The foaming agent is selected from any one or more of azodicarbonamide, N,N-dinitrospentylmethyltetramine, diisopropyl azodicarbonate and 4,4'-oxodibenzenesulfonylhydrazine. The foaming agent is selected from one or more of zinc oxide, zinc stearate, stearic acid, lead stearate, cadmium oxide, and sodium bicarbonate.

2. The foam indium heat-conducting gasket according to claim 1, characterized by The foaming agent is 0.5-4 parts.

3. The foam indium heat slug of claim 1, wherein, The stabilizer is metallic magnesium.

4. A method of producing the foam indium heat-conducting gasket as claimed in any one of claims 1 to 3, characterized by, include: The pure indium ingot, thickener, stabilizer, foaming agent, and foaming aid are mixed in a predetermined mass ratio and then prepared by chemical foaming method to obtain indium foam thermal conductive pad.

5. The production method according to claim 4, characterized by, include: A thickener and a stabilizer are added to the indium melt formed from the pure indium ingot, and the mixture is stirred thoroughly to obtain an indium melt mixture. A foaming agent and a foaming aid are added to an indium melt mixture at a first preset temperature, and the mixture is stirred thoroughly to obtain a foamed indium melt mixture; wherein the first preset temperature is greater than the melting point of the pure indium ingot; After the foamed indium melt mixture is injection molded, it is cut according to preset requirements to obtain foamed indium thermal conductive pads.

6. The method of claim 5, wherein, The step involves adding a thickener and a stabilizer to the indium melt formed from the pure indium ingot, and then thoroughly stirring to obtain an indium melt mixture; comprising: The pure indium ingot is heated to 170-180°C and held at that temperature for 20-30 minutes to obtain indium melt. After adding a thickener and a stabilizer to the indium melt, the mixture is stirred thoroughly at a stirring speed of 1000-1500 r / min to generate an indium melt mixture.

7. The method of claim 5, wherein, The addition of a foaming agent and a foaming aid to the indium melt mixture at a first preset temperature, followed by thorough stirring, yields a foamed indium melt mixture; comprising: The indium melt mixture is heated to 190-220°C; Add a foaming agent and a foaming aid to the heated indium melt mixture and stir thoroughly to obtain a foamed indium melt mixture.

8. The method of claim 5, wherein, The process of molding the foamed indium melt mixture and then cutting it according to preset requirements to obtain a foamed indium thermally conductive pad includes: The foamed indium melt mixture is poured into a mold and held at 190-220 degrees Celsius for 2-5 minutes; then cooled to solidify and the foamed indium is removed from the mold at 60-70 degrees Celsius. After the indium foam cools to room temperature, it is cut to a preset size to obtain an indium foam thermal conductive pad.

9. Use of a foam indium heat-conducting gasket according to any one of claims 1-3 in an electronic device, characterized in that, The indium foam is bonded to the surface of the electronic device to transfer the heat generated by the electronic device to the heat sink.

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