Method for applying liquid metal as thermal interface material

Abstract

The invention discloses a method for applying liquid metal as a thermal interface material, and relates to the technical field of thermal management. The liquid metal with high thermal conductivity is selected as a core heat-conducting medium, the liquid metal shows excellent heat-conducting performance at the normal temperature, the gallium-indium-tin alloy with high thermal conductivity is selected as the core heat-conducting medium, the heat-conducting performance of the thermal interface material is remarkably improved, and the heat-conducting performance of the thermal interface material is greatly improved at the normal temperature. The liquid metal shows excellent heat conduction performance and can form an almost unobstructed heat conduction path, so that heat generated by the electronic equipment is quickly transferred to the radiator, in addition, in combination with the intelligent response material layer, the shape memory polymer is subjected to phase change at a specific temperature, the liquid metal is driven to form a closer contact interface, and the heat dissipation efficiency is improved. The interface thermal resistance is further reduced, and the heat conduction efficiency is remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of thermal management, and in particular to a method for using liquid metal as a thermal interface material. Background Art

[0002] With the rapid development of science and technology, the power density and integration of electronic devices, especially high-performance computing devices, continue to increase, resulting in a large amount of heat generated by these devices during operation. How to effectively transfer this heat from the heat source to the heat sink has become a key issue that needs to be urgently solved in the field of thermal management technology.

[0003] Although traditional thermal interface materials can meet the heat dissipation needs to a certain extent, their thermal conductivity gradually shows limitations in high power density application scenarios. These materials often have low thermal conductivity, large thermal resistance, and easy aging problems, making it difficult to meet the growing heat dissipation needs. Therefore, a method for applying liquid metal as a thermal interface material is proposed. Summary of the invention

[0004] The purpose of the present invention is to make up for the deficiencies of the prior art and provide a method for developing liquid metal as a thermal interface material. The liquid metal provided by the present invention is used as a thermal interface material. Through the phase change characteristics of the intelligent response material, it can automatically adjust its shape under specific conditions to form a tighter contact interface, thereby significantly improving the thermal conductivity. At the same time, the setting of the encapsulation layer effectively prevents the leakage of the liquid metal and the influence of the external environment, thereby ensuring the stability and reliability of the material.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for using liquid metal as a thermal interface material, the specific steps of the method are:

[0006] S100, preparation of liquid metal layer: liquid metal with high thermal conductivity is selected as the core thermal conductive medium. The liquid metal exhibits excellent thermal conductivity at room temperature;

[0007] S200, preparation and combination of smart response material layer: Covering on and mixed with the liquid metal layer, shape memory polymer smart materials are used. These materials can undergo phase change from solid to elastic state at a specific temperature threshold, thereby driving the liquid metal to form a closer contact interface and enhance thermal conductivity;

[0008] S300, packaging and application: In order to protect the internal materials and prevent the leakage of liquid metal, high temperature resistant and corrosion resistant packaging materials are used to package the whole.

[0009] Furthermore, the specific steps of S100 are:

[0010] S101, Material Selection: In-depth research was conducted on a variety of liquid metals, focusing on their thermal conductivity, melting point, chemical stability, toxicity and cost factors, and Gallium Indium Tin alloy was selected as the core thermal conductive medium;

[0011] S102, alloy preparation: Use a high-precision balance to accurately weigh the three metal raw materials of gallium, indium and tin according to the predetermined ratio of gallium: indium: tin = 1:2:3. For an alloy with a total mass of M grams, the mass of gallium is weighed as Mx / (x+y+z) grams, the mass of indium is weighed as My / (x+y+z) grams, and the mass of tin is weighed as Mz / (x+y+z) grams. To prepare 100 grams of alloy, the mass of gallium is weighed as 100×1(x+y+z) grams, and the mass of indium is weighed as My / (x+y+z) grams. Grams, the mass of tin is weighed as Mz / (x+y+z) grams, the weighed metal raw materials are placed in a furnace under vacuum and inert gas protection, heated to completely melt the metal and mix it evenly, and the heating rate, temperature and heating rate are controlled, wherein the heating rate = (final temperature - initial temperature) / heating time, that is, the metal raw material with an initial temperature of 20°C is heated to 800°C within 2 hours, then the heating rate is (800-20) / (2×60) = 6.33°C / minute, and the molten alloy liquid is slowly cooled to room temperature;

[0012] S103, coating or injection: the prepared gallium indium tin alloy is heated again to a molten state, and according to the specific application scenario, the liquid metal is coated on a substrate of a preset shape by a melting process, or injected into a specific mold, and the coated or injected liquid metal is rapidly cooled to fix its shape and prevent it from flowing before re-solidification;

[0013] S104, thermal conductivity test: Use professional thermal conductivity test equipment to test the thermal conductivity of the prepared liquid metal layer to evaluate the stability of the liquid metal layer under different temperatures, humidity and chemical environments.

[0014] Furthermore, the specific steps of S100 also include packaging treatment: in order to prevent the liquid metal from leaking and being affected by the external environment, the liquid metal layer is packaged, and packaging materials are selected, including high-temperature resistant and corrosion-resistant polymers and metal foils, which are tightly wrapped around the outside of the liquid metal layer to form a stable composite material structure.

[0015] Furthermore, the specific steps of S200 are:

[0016] S201, Material selection and processing: Select shape memory polymers with phase transition temperature, good shape memory effect, chemical stability and compatibility with liquid metal, melt, mix, extrude and injection mold the polymer raw materials to prepare films, fibers and preforms of specific shapes;

[0017] S202, liquid metal layer preparation: the gallium indium tin alloy has been prepared according to the above steps, ensuring that the surface of the liquid metal layer is clean and free of impurities and is in a stable state;

[0018] S203, covering and embedding: gently covering the shape memory polymer film and preform on the surface of the liquid metal layer, using a special process to embed the polymer fibers or particles into the liquid metal. If a stronger bonding force is required between the polymer and the liquid metal, the composite material can be subjected to a short heat treatment without damaging the performance of the liquid metal to promote interface fusion;

[0019] S204, installation of temperature control system: install a temperature control system around the composite material, set heating elements and temperature sensors to control the ambient temperature. When the ambient temperature reaches a preset specific temperature threshold, the shape memory polymer will undergo a phase change from a solid state to an elastic state, thereby changing its shape and volume. During the phase change process, the deformation of the shape memory polymer will drive the liquid metal layer to form a closer contact interface.

[0020] Furthermore, the specific step S200 further includes:

[0021] S205, performance verification and adjustment, conduct thermal conductivity tests on the composite material to verify the change in thermal conductivity before and after the phase change, observe the contact interface between the liquid metal and the shape memory polymer through microscopy and imaging technology, and evaluate the effect of the phase change on the interface morphology. According to the test results, adjust the phase change temperature of the shape memory polymer, the ratio of the liquid metal, and the preparation process parameters of the composite material. After completing the performance verification, encapsulate the composite material to protect it from the external environment and ensure its stability and reliability during use. Subsequently, the composite material is used in situations where efficient heat conduction is required, including electronic equipment heat dissipation and thermal management systems.

[0022] Furthermore, the S203 special process is specifically as follows:

[0023] Step 1: Pre-treat the liquid metal layer: Ensure that the surface of the gallium-indium-tin alloy is clean and free of impurities. Use ultrasonic cleaning or chemical cleaning to heat the liquid metal layer to a temperature slightly higher than its melting point so that its surface is slightly melted to form a smoother and easier-to-bond interface.

[0024] Step 2: Preheating the polymer material: Preheating the shape memory polymer film, preform or fiber to soften it and provide better embedding performance. The preheating temperature should be lower than its phase transition temperature to avoid unnecessary phase change during the embedding process.

[0025] Step 3: Embedding process: gently cover the preheated shape memory polymer film on the surface of the liquid metal layer to ensure that there are no bubbles or wrinkles. For preforms, place them at specific locations on the liquid metal layer according to design requirements. For situations where polymer fibers or particles need to be embedded in liquid metal, one of the following methods can be used:

[0026] Mechanical embedding: using specially designed mechanical devices including but not limited to precision needles and micro rollers to press polymer fibers or particles into the liquid metal layer to control the embedding depth and uniformity;

[0027] Chemically assisted embedding: using the surface tension difference between polymer and liquid metal, combined with chemical solvents or surfactants, to assist the embedding process of polymer fibers or particles;

[0028] Heat treatment: Without affecting the performance of the liquid metal, the composite material is subjected to a short heat treatment to promote the interface fusion between the liquid metal and the shape memory polymer and enhance the bonding strength;

[0029] Step 3: Cooling and curing: After embedding, the composite material is quickly cooled to fix the shape of the liquid metal and prevent it from flowing before re-solidification. For the shape memory polymer part that needs to be cured, the appropriate curing conditions are selected according to the material properties for curing.

[0030] Step 4: Interface detection: Use a microscope, imaging technology or other non-destructive detection methods to detect the contact interface between the liquid metal and the shape memory polymer to ensure that there are no defects or cracks, and evaluate the bonding quality of the interface.

[0031] Furthermore, the specific steps of S300 are:

[0032] S301, packaging material selection and pretreatment: According to the characteristics of the internal materials, select packaging materials with sufficient high temperature resistance and corrosion resistance, as well as good sealing and mechanical strength. Common packaging materials include ceramics, metal alloys, and high temperature resistant polymers. Perform necessary pretreatment on the packaging materials, including cleaning, drying, cutting and molding, to prepare for subsequent packaging operations;

[0033] S302, mold design and manufacturing: design the packaging mold according to the shape and size of the internal material, reserve necessary interfaces for subsequent connection and installation, and use the correct processing method to manufacture the packaging mold;

[0034] S303, internal material inspection: The liquid metal layer and the smart response material layer have been prepared according to the previous steps and are in a stable state. At the same time, check whether the internal materials have any damage and contamination, and repair and clean them if necessary.

[0035] Furthermore, the specific steps of S300 also include:

[0036] S304, packaging operation: placing the internal material in the packaging mold, closely fitting with the inner wall of the mold without gaps and misalignment. If the packaging material is liquid or semi-solid, the packaging material is injected into the mold through an injection molding machine and other equipment until it completely covers the internal material and fills the mold space. For packaging materials that need to be cured, they are placed under appropriate temperature conditions for curing. At the same time, all types of packaging materials need to be cooled to reach a stable physical and chemical state;

[0037] S305, post-packaging processing and application: After the packaging material is completely solidified and cooled, take out the packaged whole from the mold, perform an appearance inspection on the packaged whole, clean up the waste and residues generated during the packaging process, organize the packaging equipment and tools, apply the packaged whole to the required occasion, and perform installation and connection operations according to specific needs.

[0038] Furthermore, the application of the material is specifically as follows:

[0039] Selection and preparation of liquid metal: The selection of liquid metal is the key to efficient heat conduction. Considering the factors of melting point, thermal conductivity, fluidity and chemical stability, gallium indium tin alloy is widely used due to its low melting point, high thermal conductivity and good fluidity. The preparation process of this alloy includes material selection, alloy preparation, coating or injection and thermal conductivity testing to ensure that the alloy has stable performance and adapts to various application environments;

[0040] Selection and integration of smart response materials: The selection of smart response materials is based on their phase change temperature, deformation recovery ability and compatibility with liquid metal. Shape memory alloys and thermosensitive polymers are two commonly used smart response materials. They can undergo reversible shape and volume changes at a specific temperature. Through micro-nano processing technology, the smart response material layer is precisely embedded on the surface or inside of the liquid metal to achieve fine control of the liquid metal behavior.

[0041] Precision mold and packaging technology: The use of precision mold technology to prepare composite materials of liquid metal and intelligent response materials can effectively avoid the generation of bubbles and defects, ensure the quality and performance of the materials, and at the same time, use high temperature resistant and corrosion resistant packaging materials to package the whole to protect the internal materials from the influence of the external environment and improve the stability and reliability of the materials;

[0042] Installation and application: Use special installation tools to accurately attach the prepared adaptive thermal interface material between the electronic component and the radiator. Use the pressure regulating device to moderately pressurize the thermal interface material to further eliminate bubbles and gaps, ensure that the liquid metal fits tightly with the interfaces on both sides, and regularly check and adjust the fixture to ensure that the thermal interface material always maintains the best condition during use;

[0043] Heat conduction mechanism: When the device is running, as the temperature rises, the smart response material reaches its phase change threshold and begins to deform. This deformation pushes the liquid metal to fit more closely to the interfaces on both sides and fills the tiny gaps caused by thermal expansion and mechanical vibration. With its high thermal conductivity, the liquid metal, with the assistance of the smart response material, forms an almost unobstructed heat conduction path, which quickly conducts the heat generated by the electronic components to the radiator, thereby achieving efficient heat dissipation.

[0044] Compared with the existing technology, the method of using liquid metal as thermal interface material has the following beneficial effects:

[0045] 1. The liquid metal of the present invention is used as a thermal interface material application method. By selecting a gallium-indium-tin alloy with high thermal conductivity as the core thermal conductive medium, the thermal conductivity of the thermal interface material is significantly improved. At room temperature, the liquid metal exhibits excellent thermal conductivity and can form an almost unobstructed heat conduction path, thereby quickly transferring the heat generated by the electronic device to the radiator. In addition, combined with the intelligent response material layer, at a specific temperature, the shape memory polymer undergoes a phase change, driving the liquid metal to form a closer contact interface, further reducing the interface thermal resistance and significantly improving the heat conduction efficiency. This effect is particularly significant in the heat dissipation of high-power density electronic equipment, effectively ensuring the stable operation of the equipment.

[0046] 2. The liquid metal thermal interface material of the present invention has an adaptive adjustment function. When the equipment is running, as the temperature rises, the intelligent response material reaches its phase change threshold and begins to deform, pushing the liquid metal to fit more closely to the interfaces on both sides, filling the tiny gaps caused by thermal expansion and mechanical vibration, and ensuring the continuity and efficiency of the heat conduction path. This adaptive adjustment mechanism enables the thermal interface material to maintain excellent thermal conductivity under different working conditions without human intervention. At the same time, the whole is packaged with high-temperature resistant and corrosion-resistant packaging materials, which effectively prevents the leakage of liquid metal and the influence of the external environment, and ensures the long-term stability and reliability of the composite material structure during use. These characteristics enable the liquid metal thermal interface material of the present invention to still work stably in harsh environments, thereby extending the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0048] Figure 1 A flow chart of a method for applying liquid metal as a thermal interface material. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Embodiment 1

[0051] Based on thermal conductivity, melting point, chemical stability and toxicity, gallium-indium-tin alloy was selected as the core thermal conductive medium. High-quality gallium, indium and tin metal raw materials were purchased from reputable suppliers. A high-precision balance was used to accurately weigh the gallium, indium and tin metal raw materials in a predetermined proportion. These metal raw materials were placed in a special furnace and heated to a temperature higher than the melting point of each component under vacuum and inert gas protection environment to completely melt the metal and mix it evenly. The heating rate and temperature were controlled to avoid unnecessary oxidation and contamination. Subsequently, the molten alloy liquid was slowly cooled to room temperature and solidified into a solid state. It was heated again to a molten state and prepared for coating. According to the specific shape and size of the CPU substrate, a coating mold was designed to evenly coat the molten gallium-indium-tin alloy on the CPU substrate of a preset shape. The precise coating process ensured that the thickness of the liquid metal layer was uniform and free of bubbles and impurities. After coating, the liquid metal layer was quickly cooled to fix its shape and prevent it from flowing before re-solidification.

[0052] Select shape memory polymers with suitable phase change temperature, good shape memory effect and chemical stability as intelligent response materials, purchase the required raw materials from reliable suppliers, and carry out necessary processing. Gently cover the prepared shape memory polymer film on the surface of the cooled liquid metal layer to ensure good contact between the two but not excessive mixing, thereby enhancing the bonding force between the two. Install a temperature control system between the CPU and the radiator, including a heating element and a temperature sensor. Set a specific temperature threshold through programming. When the CPU temperature rises to this threshold, the temperature control system starts to provide the necessary heat for the shape memory polymer to cause it to undergo a phase change.

[0053] In view of the high temperature and high pressure characteristics of the CPU working environment, a ceramic material with high temperature resistance, corrosion resistance and good sealing is selected as the packaging layer to ensure that the packaging material can operate stably for a long time and is not affected by the external environment. The CPU substrate and the covered intelligent response material layer are thoroughly cleaned and dried, and a packaging mold matching the shape of the CPU substrate is designed and manufactured. The internal material is carefully placed in the mold, and the pre-treated ceramic packaging material is injected and cured. After the curing is completed, the package body is strictly inspected for appearance and tested for performance.

[0054] Use special installation tools to accurately attach the packaged thermal interface material between the CPU and the radiator. By fine-tuning the fixture, ensure that the thermal interface material will not loosen or fall off due to vibration and temperature changes during long-term use. Use the pressure regulating device to moderately pressurize the thermal interface material to further eliminate potential bubbles and gaps and improve heat conduction efficiency. Regularly check and adjust the fixture to ensure that the thermal interface material always maintains the best contact state. Implement a regular maintenance plan, including checking the appearance integrity of the thermal interface material, the tightness of the contact surface and the heat conduction efficiency. Use infrared thermal imaging technology to monitor the working status of the thermal interface material in real time, and promptly discover and solve potential problems. At the same time, pay attention to new technology trends in the industry and upgrade to more advanced and efficient adaptive thermal interface materials in a timely manner to meet the ever-increasing heat dissipation needs. In the process of material selection and preparation, always consider environmental factors, select non-toxic, recyclable and biodegradable materials to reduce the impact on the environment.

[0055] Embodiment 2

[0056] Gallium indium tin alloy is selected as the core thermal conductive medium, and high-quality metal raw materials are purchased from reliable suppliers. According to the specific shape and size of the smartphone motherboard, a precise liquid metal injection mold is designed. The mold must have high precision, high temperature resistance and corrosion resistance. The liquid metal injects the molten gallium indium tin alloy into the pre-designed mold. Precise control is used to ensure that the liquid metal is evenly filled without bubbles and impurities. The liquid metal is then quickly cooled to solidify into a stable shape and tightly bonded to the inner wall of the mold.

[0057] Select shape memory polymers that are suitable for the size and temperature range of smartphones. Considering the thin and light design of mobile phones, the polymer needs to exist in the form of tiny particles and fibers. Purchase polymer raw materials from reliable suppliers and process them into the required form through special processes. Utilize micro-nano processing technology to accurately embed polymer particles and fibers into the cooled liquid metal layer. By precisely controlling the embedding depth and position, ensure that the interface between the polymer and the liquid metal is tightly bonded without destroying the uniformity of the liquid metal layer. Under the premise of not damaging the performance of the liquid metal, the embedded composite material is briefly heat treated to promote the interface fusion between the polymer and the liquid metal and enhance the bonding strength.

[0058] In view of the requirements for the lightness and flexibility of smartphone motherboards, high-temperature resistant, corrosion-resistant and flexible polymers are selected as packaging materials to ensure that the packaging materials can tightly wrap the internal thermal interface materials and adapt to the bending and deformation of the mobile phone motherboard. The packaging materials are pretreated as necessary, and flexible molds are designed and manufactured to adapt to the shape of the mobile phone motherboard. The internal materials are placed in the mold, and the packaging materials are injected and cured. The temperature and time need to be controlled during the curing process to ensure that the packaging materials can be completely cured and tightly combined with the internal materials. After the packaging is completed, strict appearance inspection and performance testing are carried out. Microscopes and imaging technology are used to observe the combination of the packaging layer and the internal materials to ensure that they are tight and without gaps.

[0059] Use a special installation tool to accurately attach the packaged thermal interface material between the smartphone motherboard and the heat sink. Due to the limited internal space of the mobile phone, special attention should be paid to keeping the contact surface flat and tightly fitted. Considering the impact of the vibration and temperature changes of the mobile phone motherboard on the heat dissipation effect, a special adhesive is used to fix the thermal interface material. The adhesive must have the characteristics of high temperature resistance, vibration resistance and long-term stability. Use a micro pressure regulating device to moderately pressurize the thermal interface material to further eliminate potential bubbles and gaps. At the same time, use appropriate fixing methods to ensure that the thermal interface material will not loosen or fall off during long-term use.

[0060] Implementing a regular maintenance plan includes checking the appearance integrity of the thermal interface material, the tightness of the contact surface, and whether there are signs of aging and damage. Using special tools to clean dust and dirt on the surface of the heat dissipation module to maintain heat dissipation efficiency, using infrared thermal imaging technology to regularly detect the thermal conductivity efficiency of the thermal interface material and the heat dissipation effect of the mobile phone motherboard, evaluating the performance of the heat dissipation module based on the test results and adjusting the maintenance plan in a timely manner, paying attention to new industry technology trends and upgrading to more advanced and efficient adaptive thermal interface materials in a timely manner to meet the ever-increasing heat dissipation needs, and always considering environmental factors in the material selection and preparation process, using non-toxic, recyclable and biodegradable materials to reduce the impact on the environment.

[0061] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for using liquid metal as a thermal interface material, characterized in that: The specific steps of this method are: S100, preparation of liquid metal layer: liquid metal with high thermal conductivity is selected as the core thermal conductive medium. The liquid metal exhibits excellent thermal conductivity at room temperature; S200, preparation and combination of smart response material layer: Covering on and mixed with the liquid metal layer, shape memory polymer smart materials are used. These materials can undergo phase change from solid to elastic state at a specific temperature threshold, thereby driving the liquid metal to form a closer contact interface and enhance thermal conductivity; S300, packaging and application: In order to protect the internal materials and prevent the leakage of liquid metal, high temperature resistant and corrosion resistant packaging materials are used to package the whole.

2. The method for using liquid metal as a thermal interface material according to claim 1, characterized in that: The specific steps of S100 are: S101, Material Selection: In-depth research was conducted on a variety of liquid metals, focusing on their thermal conductivity, melting point, chemical stability, toxicity and cost factors, and Gallium Indium Tin alloy was selected as the core thermal conductive medium; S102, alloy preparation: Use a high-precision balance to accurately weigh the three metal raw materials of gallium, indium and tin according to the predetermined ratio of gallium: indium: tin = 1:2:

3. For an alloy with a total mass of M grams, the mass of gallium is weighed as Mx / (x+y+z) grams, the mass of indium is weighed as My / (x+y+z) grams, and the mass of tin is weighed as Mz / (x+y+z) grams. To prepare 100 grams of alloy, the mass of gallium is weighed as 100×1(x+y+z) grams, and the mass of indium is weighed as My / (x+y+z) grams. Grams, the mass of tin is weighed as Mz / (x+y+z) grams, the weighed metal raw materials are placed in a furnace under vacuum and inert gas protection, heated to completely melt the metal and mix it evenly, and the heating rate, temperature and heating rate are controlled, wherein the heating rate = (final temperature - initial temperature) / heating time, that is, the metal raw material with an initial temperature of 20°C is heated to 800°C within 2 hours, then the heating rate is (800-20) / (2×60) = 6.33°C / minute, and the molten alloy liquid is slowly cooled to room temperature; S103, coating or injection: the prepared gallium indium tin alloy is heated again to a molten state, and according to the specific application scenario, the liquid metal is coated on a substrate of a preset shape by a melting process, or injected into a specific mold, and the coated or injected liquid metal is rapidly cooled to fix its shape and prevent it from flowing before re-solidification; S104, thermal conductivity test: Use professional thermal conductivity test equipment to test the thermal conductivity of the prepared liquid metal layer to evaluate the stability of the liquid metal layer under different temperatures, humidity and chemical environments.

3. The method for using liquid metal as a thermal interface material according to claim 2, characterized in that: The specific steps of S100 also include packaging treatment: in order to prevent the liquid metal from leaking and being affected by the external environment, the liquid metal layer is packaged, and packaging materials are selected, including high-temperature resistant and corrosion-resistant polymers and metal foils, which are tightly wrapped around the outside of the liquid metal layer to form a stable composite material structure.

4. The method for using liquid metal as a thermal interface material according to claim 1, characterized in that: The specific steps of S200 are: S201, Material selection and processing: Select shape memory polymers with phase transition temperature, good shape memory effect, chemical stability and compatibility with liquid metal, melt, mix, extrude and injection mold the polymer raw materials to prepare films, fibers and preforms of specific shapes; S202, liquid metal layer preparation: the gallium indium tin alloy has been prepared according to the above steps, ensuring that the surface of the liquid metal layer is clean and free of impurities and is in a stable state; S203, covering and embedding: gently covering the shape memory polymer film and preform on the surface of the liquid metal layer, using a special process to embed the polymer fibers or particles into the liquid metal. If a stronger bonding force is required between the polymer and the liquid metal, the composite material can be subjected to a short heat treatment without damaging the performance of the liquid metal to promote interface fusion; S204, installation of temperature control system: install a temperature control system around the composite material, set heating elements and temperature sensors to control the ambient temperature. When the ambient temperature reaches a preset specific temperature threshold, the shape memory polymer will undergo a phase change from a solid state to an elastic state, thereby changing its shape and volume. During the phase change process, the deformation of the shape memory polymer will drive the liquid metal layer to form a closer contact interface.

5. The method for using liquid metal as a thermal interface material according to claim 4, characterized in that: The specific steps of S200 also include: S205, performance verification and adjustment, conduct thermal conductivity tests on the composite material to verify the change in thermal conductivity before and after the phase change, observe the contact interface between the liquid metal and the shape memory polymer through microscopy and imaging technology, and evaluate the effect of the phase change on the interface morphology. According to the test results, adjust the phase change temperature of the shape memory polymer, the ratio of the liquid metal, and the preparation process parameters of the composite material. After completing the performance verification, encapsulate the composite material to protect it from the external environment and ensure its stability and reliability during use. Subsequently, the composite material is used in situations where efficient heat conduction is required, including electronic equipment heat dissipation and thermal management systems.

6. The method for using liquid metal as a thermal interface material according to claim 4, characterized in that: The special process of S203 is specifically as follows: Step 1: Pre-treat the liquid metal layer: Ensure that the surface of the gallium-indium-tin alloy is clean and free of impurities. Use ultrasonic cleaning or chemical cleaning to heat the liquid metal layer to a temperature slightly higher than its melting point so that its surface is slightly melted to form a smoother and easier-to-bond interface. Step 2: Preheating the polymer material: Preheating the shape memory polymer film, preform or fiber to soften it and provide better embedding performance. The preheating temperature should be lower than its phase transition temperature. Step 3: Embedding process: gently cover the preheated shape memory polymer film on the surface of the liquid metal layer. For preforms, place them at specific locations on the liquid metal layer according to design requirements. For situations where polymer fibers or particles need to be embedded in liquid metal, one of the following methods can be used: Mechanical embedding: using specially designed mechanical devices including but not limited to precision needles and micro rollers to press polymer fibers or particles into the liquid metal layer to control the embedding depth and uniformity; Chemically assisted embedding: using the surface tension difference between polymer and liquid metal, combined with chemical solvents or surfactants, to assist the embedding process of polymer fibers or particles; Heat treatment: Without affecting the performance of the liquid metal, the composite material is subjected to a short heat treatment to promote the interface fusion between the liquid metal and the shape memory polymer and enhance the bonding strength; Step 3: Cooling and curing: After embedding, the composite material is quickly cooled to fix the shape of the liquid metal and prevent it from flowing before re-solidification. For the shape memory polymer part that needs to be cured, the appropriate curing conditions are selected according to the material properties for curing. Step 4: Interface detection: Use a microscope, imaging technology or other non-destructive detection methods to detect the contact interface between the liquid metal and the shape memory polymer.

7. The method for using liquid metal as a thermal interface material according to claim 1, characterized in that: The specific steps of S300 also include: S301, packaging material selection and pretreatment: According to the characteristics of the internal materials, select packaging materials with sufficient high temperature resistance and corrosion resistance, as well as good sealing and mechanical strength. Common packaging materials include ceramics, metal alloys, and high temperature resistant polymers. Perform necessary pretreatment on the packaging materials, including cleaning, drying, cutting and molding, to prepare for subsequent packaging operations; S302, mold design and manufacturing: design the packaging mold according to the shape and size of the internal material, reserve necessary interfaces for subsequent connection and installation, and use the correct processing method to manufacture the packaging mold; S303, internal material inspection: The liquid metal layer and the smart response material layer have been prepared according to the previous steps and are in a stable state. At the same time, check whether the internal materials have any damage and contamination, and repair and clean them if necessary.

8. The method for using liquid metal as a thermal interface material according to claim 7, characterized in that: The S300 specifically includes: S304, packaging operation: placing the internal material in the packaging mold, closely fitting with the inner wall of the mold without gaps and misalignment. If the packaging material is liquid or semi-solid, the packaging material is injected into the mold through an injection molding machine and other equipment until it completely covers the internal material and fills the mold space. For packaging materials that need to be cured, they are placed under appropriate temperature conditions for curing. At the same time, all types of packaging materials need to be cooled to reach a stable physical and chemical state; S305, post-packaging processing and application: After the packaging material is completely solidified and cooled, take out the packaged whole from the mold, perform an appearance inspection on the packaged whole, clean up the waste and residues generated during the packaging process, organize the packaging equipment and tools, apply the packaged whole to the required occasion, and perform installation and connection operations according to specific needs.

9. A method for using liquid metal as a thermal interface material according to any one of claims 1 to 8, characterized in that: The specific applications of this material are: Selection and preparation of liquid metal: The selection of liquid metal is the key to efficient heat conduction. Considering the factors of melting point, thermal conductivity, fluidity and chemical stability, gallium indium tin alloy is widely used due to its low melting point, high thermal conductivity and good fluidity. The preparation process of this alloy includes material selection, alloy preparation, coating or injection and thermal conductivity testing. Selection and integration of smart response materials: The selection of smart response materials is based on their phase change temperature, deformation recovery ability and compatibility with liquid metal. Shape memory alloys and thermosensitive polymers are two commonly used smart response materials. They can undergo reversible shape and volume changes at a specific temperature. Through micro-nano processing technology, the smart response material layer can be precisely embedded on the surface or inside the liquid metal; Precision mold and packaging technology: Use precision mold technology to prepare the composite material of liquid metal and intelligent response material. At the same time, use high temperature resistant and corrosion resistant packaging materials to encapsulate the whole to protect the internal materials from the influence of the external environment. Installation and application: Use special installation tools to accurately attach the prepared adaptive thermal interface material between the electronic component and the heat sink. Use the pressure regulating device to moderately pressurize the thermal interface material to further eliminate bubbles and gaps. Regularly check and adjust the fixture; Heat conduction mechanism: When the device is running, as the temperature rises, the smart response material reaches its phase change threshold and begins to deform. This deformation pushes the liquid metal to fit more closely to the interfaces on both sides and fills the tiny gaps caused by thermal expansion and mechanical vibration. With its high thermal conductivity, the liquid metal, with the assistance of the smart response material, forms an almost unobstructed heat conduction path, which quickly conducts the heat generated by the electronic components to the radiator.

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