Preparation method and application of integrated self-sealing liquid metal heat-conducting gasket

Abstract

The invention discloses a preparation method and application of an integrated self-sealing liquid metal heat-conducting gasket, and relates to the technical field of sealing materials.The preparation method comprises the following steps that S100, material selection is conducted, specifically, polyimide is selected as a substrate of the gasket, a polymer composite material doped with carbon nanotubes is used for sensing pressure changes, and the temperature of the substrate is increased; the gallium-indium-tin alloy which is in a liquid state at the room temperature and can change the viscosity through an electric field is selected as a liquid metal material, pressure induction and liquid metal viscosity adjustment are combined, the gasket can sense pressure changes and automatically adjust the viscosity of liquid metal, and therefore precise adaptation to sealing requirements under different working conditions is achieved; the sealing performance of the gasket is greatly improved due to the self-adaptive capacity, leakage can be effectively prevented especially in equipment needing to be started and stopped frequently, and stable operation of the equipment is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of sealing materials, and in particular to a preparation method and application of an integrated self-sealing liquid metal thermally conductive gasket. Background Art

[0002] In the modern industrial field, the performance of sealing materials is crucial to the normal operation and reliability of various equipment. With the continuous development of industrial technology, the working conditions of equipment are becoming increasingly complex and demanding, and the requirements for sealing materials are becoming higher and higher. In many application scenarios, such as industrial machinery and automobile engines, the frequent start and stop of equipment leads to rapid changes in internal pressure and temperature, which poses a huge challenge to the sealing performance, adaptability and stability of sealing materials.

[0003] In the prior art, some attempts have been made to improve the sealing performance and adaptability of sealing materials by changing their physical and chemical properties, such as using shape memory alloys and electroactive polymers. However, these methods often have some limitations. Although shape memory alloys can respond to temperature changes, their adaptability under pressure changes is poor. Although electroactive polymers can respond to electric fields, their thermal conductivity and mechanical strength are insufficient. In addition, the viscosity adjustment and sealing performance control of existing liquid metal sealing materials are still technical difficulties. At present, there is no liquid metal sealing material that can simultaneously achieve pressure sensing and viscosity adjustment to meet the sealing requirements under complex working conditions.

[0004] In summary, existing sealing materials have certain limitations when dealing with complex working conditions and cannot meet the requirements of sealing performance, adaptability and reliability at the same time. Therefore, it is of great significance to develop a new type of integrated self-sealing thermal conductive gasket based on pressure sensing and adjustable viscosity liquid metal. Summary of the invention

[0005] The purpose of the present invention is to make up for the shortcomings of the prior art and to provide a method for preparing an integrated self-sealing liquid metal thermal gasket and its application. It can automatically adjust the viscosity of the liquid metal in real time through pressure sensing, so as to more accurately adapt to changes in sealing requirements, greatly improve the reliability of the seal, and reduce equipment failures and maintenance costs caused by sealing failure.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: On the one hand, a method for preparing an integrated self-sealing liquid metal thermally conductive gasket comprises the following steps:

[0007] S100, material selection: polyimide is selected as the substrate of the gasket, a polymer composite material doped with carbon nanotubes (CNTs) is used to sense pressure changes, and a gallium indium tin alloy that is liquid at room temperature and can change its viscosity through an electric field is selected as the liquid metal material;

[0008] S200, gasket structure design: The gasket adopts a multi-layer composite structure, which includes a protective layer, a pressure sensing layer, a liquid metal layer and a base layer from the outside to the inside;

[0009] S300, uniform mixing and dispersion: liquid metal gallium indium tin alloy and polymer composite material doped with carbon nanotubes (CNTs) are placed in a stirring container, mixed, and the stirring speed and time are gradually adjusted while monitoring the uniformity of the mixture;

[0010] S400, viscosity adjustment mechanism under external stimulation: using a variable voltage power supply and an electrode plate, an electric field is formed on the liquid metal layer by applying voltage, thereby changing the viscosity of the liquid metal;

[0011] S500, assembly and molding curing: inject the mixture after adjusting the viscosity by external stimulation into the mold for cooling and curing, so that the liquid metal thermal conductive gasket forms a stable structure in the mold, and continuously monitor the parameters of temperature and pressure, and assemble each layer in sequence to form a complete integrated self-sealing liquid metal thermal conductive gasket;

[0012] S600, performance testing and optimization: Comprehensive performance testing of the integrated self-sealing liquid metal thermal pad after molding, including sealing performance test, thermal conductivity test, pressure sensing sensitivity test and long-term stability test. According to the test results, the parameters in the preparation process are optimized and adjusted.

[0013] Furthermore, the S100 further includes:

[0014] For polymer composites doped with carbon nanotubes CNTs, the ratio is set at 1%-10%;

[0015] Conducting microstructural analysis on the selected polymer composite material to ensure that the carbon nanotubes are uniformly dispersed in the polymer matrix;

[0016] For the gallium-based alloy, the gallium content and the ratio of indium to tin are 68% gallium, 22% indium and 10% tin, and the gallium-based alloy is refined to remove tiny particles and gas inclusions therein.

[0017] Furthermore, the S200 gasket structure design includes:

[0018] Protective layer: Located on the outermost layer, it protects the internal materials from external mechanical friction and chemical erosion. It uses high molecular polymer polytetrafluoroethylene (PTFE) with a thickness of 0.1-0.5 mm, and the surface texture of the protective layer is designed to be a micro-groove structure;

[0019] Pressure sensing layer: It is located just below the protective layer and is made of a polymer composite material doped with carbon nanotubes (CNTs). It is used to sense external pressure changes and has a thickness of 0.2-0.8 mm.

[0020] Liquid metal layer: Located below the pressure sensing layer, it is made of a gallium-based alloy that remains liquid at room temperature and changes its viscosity through an electric field. Its thickness is 0.5-2 mm;

[0021] Base layer: The innermost layer, made of polyimide, serves as the basic support for the entire gasket, with a thickness of 1-3 mm.

[0022] Furthermore, the specific steps of the S200 gasket structure design are:

[0023] S201, substrate pretreatment: using solvent isopropyl alcohol and ultrasonic cleaning equipment to thoroughly clean the substrate to remove surface impurities;

[0024] S202, preparing a pressure sensing layer: dispersing CNTs in a solvent, N-methylpyrrolidone, uniformly dispersing the CNTs by ultrasonic treatment, uniformly coating the solution on the treated substrate, and heating and curing the coated sample to form a stable pressure sensing layer;

[0025] S203, preparation of liquid metal layer: heating the gallium-based alloy until it is completely melted, using photolithography technology to produce micropores and microchannel structures, injecting molten liquid metal into the pre-prepared micropores and microchannels, and forming a stable liquid metal layer after the liquid metal is cooled;

[0026] S204, preparing a protective layer: dissolving PTFE powder to form a uniform solution, coating the protective layer solution uniformly on the liquid metal layer, and heating and curing the coated sample to form a protective layer.

[0027] Furthermore, the specific steps of uniform mixing and dispersing in S300 are:

[0028] S301, initial mixing: placing the liquid metal gallium-based alloy and the carbon nanotube-doped polymer composite material into a stirring container, setting the initial stirring speed to 100-200 rpm, starting stirring, and continuing for 5-10 minutes to achieve preliminary mixing of the materials;

[0029] S302, gradually adjust the stirring parameters: gradually accelerate the stirring to 500-800 rpm, stir for 15-20 minutes, so that the materials are evenly mixed;

[0030] S303, uniformity monitoring: during the stirring process, stop stirring every 5 minutes, use a sampling tool to extract mixture samples from different positions to check the uniformity of the mixture;

[0031] S304, dispersion treatment: For agglomeration and uneven dispersion in the mixture, dispersion measures are taken, that is, high-speed shearing is used to cut the agglomerates through shear force to disperse them into smaller particles.

[0032] Furthermore, the specific steps of S400 are:

[0033] S401, electrode plate installation: installing the electrode plates on both sides of the liquid metal layer, fixing the electrode plates with conductive glue, and adjusting the spacing and positions of the electrode plates so that they can form a uniform electric field distribution on the liquid metal layer;

[0034] S402, voltage application and control: connect the variable voltage power supply and the electrode plate, apply voltage, monitor the changes of voltage and current in real time to ensure the stability of power supply output, and at the same time, use an electric field strength measuring instrument to monitor the electric field strength in the liquid metal layer to verify whether the expected electric field strength value is reached;

[0035] S403, adjusting voltage: gradually adjusting the voltage and observing the change of the viscosity of the liquid metal;

[0036] S404, viscosity adjustment mechanism: real-time monitoring of the viscosity change of the liquid metal under the action of the electric field, adjusting the magnitude and duration of the voltage according to the deviation, transmitting the signal of the pressure sensing layer to the power controller in real time, and realizing automatic adjustment of the voltage to accurately control the viscosity of the liquid metal;

[0037] S405, integrated pressure sensing and viscosity regulation: The pressure sensing layer is combined with the viscosity regulation mechanism. When the pressure sensing layer detects pressure changes, the output voltage of the variable voltage power supply is automatically adjusted through the circuit, thereby achieving instant regulation of the viscosity of the liquid metal.

[0038] Furthermore, the specific steps of S500 are:

[0039] S501, mold preparation: design and manufacture high-precision molds that match the shape and size of the gasket, thoroughly clean and pre-treat the molds, remove surface oil, impurities and oxide layers, and apply a release agent polytetrafluoroethylene coating on the inner surface of the mold;

[0040] S502, mixture injection: slowly and evenly inject the mixture after adjusting the viscosity by external stimulation into the mold. The injection process should be continuous and stable, and the injection speed and pressure should be controlled;

[0041] S503, cooling and solidification: placing the mold injected with the mixture into a cooling device, controlling the cooling speed to avoid excessive internal stress caused by excessive cooling. During the cooling process, continuously monitor the temperature distribution in the mold.

[0042] Furthermore, the S501 is coated with a release agent polytetrafluoroethylene coating on the inner surface of the mold with a thickness of 0.05 mm, and is slowly and evenly injected into the mold at a speed of 5-10 ml / s during the injection process of the S502 mixture. The injection pressure is controlled at 0.5-1 MPa, and the mold injected with the mixture is placed in a cold water bath at a temperature of 5-10°C for cooling. For a gasket with a thickness of 5 mm, the cooling time is about 30-60 minutes.

[0043] Furthermore, the S500 further includes:

[0044] S504, temperature and pressure parameter monitoring: temperature sensors and pressure sensors are installed at the injection port, center and edge of the mold. The accuracy of the temperature sensor is ±0.5°C, and the accuracy of the pressure sensor is ±0.1MPa. The temperature and pressure changes during the cooling and curing process are monitored in real time.

[0045] S505, demoulding and post-processing: After the gasket is completely cured, take out the molded gasket, conduct a preliminary appearance inspection on the demoulded gasket, and remove surface burrs and flash defects.

[0046] On the other hand, an integrated self-sealing liquid metal thermally conductive gasket is used, which is suitable for equipment that is frequently started and stopped, namely bearings, gear boxes, hydraulic systems in industrial machinery, and key components of automobile engines and transmissions.

[0047] Compared with the prior art, the preparation method and application of the integrated self-sealing liquid metal thermally conductive gasket have the following beneficial effects:

[0048] 1. The present invention combines pressure sensing with liquid metal viscosity regulation. The gasket can sense pressure changes and automatically adjust the viscosity of the liquid metal, thereby achieving precise adaptation to sealing requirements under different working conditions. This adaptive ability greatly improves the sealing performance of the gasket, especially in equipment that requires frequent start and stop, and can effectively prevent leakage to ensure stable operation of the equipment.

[0049] 2. The integrated self-sealing design adopted in the present invention simplifies the structure of the sealing system, avoids the problem of frequent replacement and maintenance of traditional sealing materials, and at the same time, reduces the manufacturing cost of the gasket by optimizing the preparation process and material selection. In addition, since the gasket has self-adjusting ability, it can maintain stable sealing performance for a long time, thereby further reducing the maintenance difficulty and cost of the equipment.

[0050] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. 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.

[0052] Figure 1 The present invention is an operation flow chart of a method for preparing an integrated self-sealing liquid metal thermally conductive gasket.

[0053] Figure 2 The present invention is a flow chart of the application of an integrated self-sealing liquid metal thermal conductive gasket. DETAILED DESCRIPTION

[0054] 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.

[0055] Embodiment 1

[0056] A method for preparing an integrated self-sealing liquid metal thermally conductive gasket. By using a material that can sense pressure changes (such as a polymer composite material doped with carbon nanotubes), the gasket can automatically adjust its sealing performance according to actual working conditions. By adjusting the viscosity of the liquid metal (such as a gallium-based alloy) through external stimulation (such as an electric field), dynamic adjustment of the liquid metal layer can be achieved, thereby improving the sealing effect of the gasket and its ability to adapt to different working conditions.

[0057] First, enter the material selection stage (S100), select polyimide as the base of the gasket, ensure that its surface is flat and free of impurities, cut and process the polyimide to make its size consistent with the design requirements, prepare a polymer composite material doped with carbon nanotubes (CNTs), dope CNTs in the polymer at a ratio of 5%, and perform microstructure analysis to ensure that the CNTs are evenly dispersed in the polymer matrix, prepare a gallium indium tin alloy, in which the gallium content is 68%, the indium content is 22%, and the tin content is 10%, and the alloy is refined to remove tiny particles and gas inclusions to make its purity meet the requirements.

[0058] Then, enter the gasket structure design stage (S200), use solvent isopropyl alcohol and ultrasonic cleaning equipment to thoroughly clean the substrate, remove surface impurities, ensure that the substrate layer is clean, disperse CNTs in solvent N-methylpyrrolidone, and evenly disperse CNTs through ultrasonic treatment. The solution is evenly coated on the treated substrate, and then the coated sample is heated and cured to form a stable pressure sensing layer with a thickness controlled at 0.5 mm. The gallium-based alloy is heated until it is completely melted, and micropores and microchannel structures are produced using photolithography technology. The molten liquid metal is injected into the pre-prepared micropores and microchannels. After the liquid metal is cooled, a stable liquid metal layer with a thickness of 1 mm is formed, and the PTFE powder is dissolved to form a uniform solution. The protective layer solution is evenly coated on the liquid metal layer, and the coated sample is heated and cured to form a protective layer with a thickness of 0.3 mm.

[0059] Subsequently, the uniform mixing and dispersion stage (S300) is entered, and the liquid metal gallium indium tin alloy and the polymer composite material doped with carbon nanotubes are placed in a stirring container, and the initial stirring speed is set to 150 rpm. Stirring is started and continued for 8 minutes to initially mix the materials, and the stirring is gradually accelerated to 600 rpm and stirred for 18 minutes to uniformly mix the materials. During the stirring process, the stirring is stopped every 5 minutes, and a sampling tool is used to extract samples of the mixture from different positions. The uniformity of the mixture is observed through a microscope. For the agglomeration and uneven dispersion found, high-speed shearing dispersion measures are taken to cut the agglomerates through shear force to disperse them into smaller particles to ensure the uniformity of the mixture.

[0060] Next, the viscosity adjustment mechanism stage under external stimulation (S400) is entered, the electrode plates are installed on both sides of the liquid metal layer, the electrode plates are fixed with conductive glue, the spacing and position of the electrode plates are adjusted so that they can form a uniform electric field distribution on the liquid metal layer, the variable voltage power supply is connected to the electrode plates, the initial voltage is applied, and the changes in voltage and current are monitored in real time to ensure the stability of the power supply output. At the same time, the electric field strength measuring instrument is used to monitor the electric field strength in the liquid metal layer to verify whether the expected electric field strength value is reached, the voltage is gradually adjusted, the change in the viscosity of the liquid metal is observed, and the viscosity change of the liquid metal under the action of the electric field is monitored in real time. The voltage is adjusted according to the deviation. The magnitude and duration of the voltage are transmitted to the power supply controller in real time to realize automatic voltage adjustment to accurately control the viscosity of the liquid metal, and the pressure sensing layer is combined with the viscosity adjustment mechanism. When the pressure sensing layer detects a pressure change, the output voltage of the variable voltage power supply is automatically adjusted through the circuit, thereby realizing instant adjustment of the viscosity of the liquid metal.

[0061] Secondly, enter the assembly and molding curing stage (S500), design and manufacture a high-precision mold that matches the shape and size of the gasket, thoroughly clean and pretreat the mold, remove surface oil, impurities and oxide layer, apply a release agent polytetrafluoroethylene coating on the inner surface of the mold with a thickness of 0.05 mm, slowly and evenly inject the mixture after adjusting the viscosity by external stimulation into the mold at a speed of 8 ml / s, and control the injection pressure at 0.8 MPa. Put the mold injected with the mixture into a cold water bath at a temperature of 8°C for cooling. For a gasket with a thickness of 5 mm, the cooling time is about 45 minutes. Install temperature sensors and pressure sensors at the injection port, mold center and edge of the mold. The accuracy of the temperature sensor is ±0.5°C, and the accuracy of the pressure sensor is ±0.1 MPa. Monitor the temperature and pressure changes in the cooling and curing process in real time. After the gasket is completely cured, take out the molded gasket, conduct a preliminary appearance inspection on the demolded gasket, and remove surface burrs and flash defects.

[0062] Finally, the performance test and optimization stage (S600) is entered, and the integrated self-sealing liquid metal thermal conductive gasket after molding is subjected to comprehensive performance tests, including sealing performance test, thermal conductivity test, pressure sensing sensitivity test and long-term stability test. In the sealing performance test, the gasket is installed in a simulation device, and different pressure and temperature conditions are applied to detect whether there is leakage. The thermal conductivity test evaluates its thermal conductivity by measuring the thermal conductivity of the gasket. The pressure sensing sensitivity test detects the response speed and accuracy of the gasket to pressure changes. The long-term stability test is to observe the performance changes of the gasket during long-term use. According to the test results, the parameters in the preparation process are optimized and adjusted. If it is found that the sealing performance is insufficient, it may be necessary to adjust the sensitivity of the pressure sensing layer or the viscosity adjustment mechanism of the liquid metal. If the thermal conductivity is not ideal, it may be necessary to optimize the structure or material selection of the liquid metal layer. The optimized gasket is applied to bearings, gearboxes, hydraulic systems in industrial machinery, and key components such as automobile engines and transmissions. In actual applications, the performance of the gasket is regularly monitored to ensure that it can effectively improve the operating efficiency and reliability of the equipment and reduce maintenance costs.

[0063] The present embodiment provides specific implementation steps of a method for preparing an integrated self-sealing liquid metal thermally conductive gasket, which uses liquid metal as a thermal conductive medium and can adjust the viscosity according to pressure changes, thereby optimizing the thermal conductivity. This helps to more effectively conduct away the heat generated during the operation of the equipment and keep the equipment within a suitable operating temperature range, thereby improving the operating efficiency and stability of the equipment and extending its service life.

[0064] Embodiment 2

[0065] This embodiment describes in detail the specific implementation process of the application of an integrated self-sealing liquid metal thermally conductive gasket. By adjusting material parameters and process conditions, the performance of the gasket is further optimized so that it can play a better role in different application scenarios.

[0066] In the specific implementation, polyimide continues to be used as the base of the gasket to maintain its good mechanical properties and chemical stability. Graphene-doped polymer composites are selected to replace the original doped carbon nanotube materials. Graphene has higher conductivity and mechanical strength, which can further improve the sensitivity and stability of pressure sensing. The proportion of graphene in the polymer matrix is ​​adjusted to 3%-5% to ensure uniform dispersion. An optimized gallium-based alloy is selected, with a specific composition of 70% gallium, 20% indium and 10% tin. Refining treatment is used to remove more tiny particles and gas inclusions to improve the purity and stability of the alloy.

[0067] The original multi-layer composite structure remains unchanged, but the thickness of each layer is slightly adjusted, that is, a polytetrafluoroethylene (PTFE) with a thickness of 0.2 mm is selected, and the surface texture is still a micro-groove structure to enhance wear resistance and corrosion resistance; the thickness is adjusted to 0.5 mm to better balance the sensing sensitivity and mechanical strength; the thickness is adjusted to 1 mm to adapt to the improved alloy properties and structural requirements; the thickness is maintained at 2 mm as a stable support layer, and the initial stirring speed is set to 150 rpm for 8 minutes to ensure that the materials are initially mixed evenly, and then accelerated to 600 rpm and stirred for 20 minutes to ensure that the materials are fully mixed. Samples are taken for monitoring every 5 minutes, and high-speed shearing and other measures are taken to deal with uneven parts.

[0068] The viscosity adjustment mechanism under external stimulation remains unchanged, but the electrode plate design and power control system are optimized to improve the uniformity of electric field distribution and the accuracy of voltage regulation to ensure the accuracy and stability of liquid metal viscosity adjustment. A 0.08 mm thick polytetrafluoroethylene release agent is applied to the inner surface of the mold to ensure smooth demolding. The mixture is injected at a rate of 8 ml / s, and the injection pressure is controlled at 0.7 MPa to ensure a smooth injection process. The mold is placed in a cold water bath at 7°C. For a 1 mm thick gasket, the cooling time is adjusted to 45 minutes to ensure uniform release of internal stress.

[0069] On the basis of comprehensive performance testing, durability testing under high temperature and high pressure environment is added to evaluate the working stability of the gasket under extreme conditions. According to the test results, the key parameters in the preparation process are further fine-tuned to ensure the overall performance of the gasket is optimized.

[0070] 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 preparing an integrated self-sealing liquid metal thermally conductive gasket, characterized in that: The preparation method comprises the following steps: S100, material selection: polyimide is selected as the substrate of the gasket, a polymer composite material doped with carbon nanotubes (CNTs) is used to sense pressure changes, and a gallium indium tin alloy that is liquid at room temperature and can change its viscosity through an electric field is selected as the liquid metal material; S200, gasket structure design: The gasket adopts a multi-layer composite structure, which includes a protective layer, a pressure sensing layer, a liquid metal layer and a base layer from the outside to the inside; S300, uniform mixing and dispersion: liquid metal gallium indium tin alloy and polymer composite material doped with carbon nanotubes (CNTs) are placed in a stirring container, mixed, and the stirring speed and time are gradually adjusted while monitoring the uniformity of the mixture; S400, viscosity adjustment mechanism under external stimulation: using a variable voltage power supply and an electrode plate, an electric field is formed on the liquid metal layer by applying voltage, thereby changing the viscosity of the liquid metal; S500, assembly and molding curing: inject the mixture after adjusting the viscosity by external stimulation into the mold for cooling and curing, so that the liquid metal thermal conductive gasket forms a stable structure in the mold, and continuously monitor the parameters of temperature and pressure, and assemble each layer in sequence to form a complete integrated self-sealing liquid metal thermal conductive gasket; S600, performance testing and optimization: Comprehensive performance testing of the integrated self-sealing liquid metal thermal pad after molding, including sealing performance test, thermal conductivity test, pressure sensing sensitivity test and long-term stability test. According to the test results, the parameters in the preparation process are optimized and adjusted.

2. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 1, characterized in that: The S100 further includes: For polymer composites doped with carbon nanotubes CNTs, the ratio is set at 1%-10%; Conducting microstructural analysis on the selected polymer composite material to ensure that the carbon nanotubes are uniformly dispersed in the polymer matrix; For the gallium-based alloy, the gallium content and the ratio of indium to tin are 68% gallium, 22% indium and 10% tin, and the gallium-based alloy is refined to remove tiny particles and gas inclusions therein.

3. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 1, characterized in that: The S200 gasket structure design includes: Protective layer: Located on the outermost layer, it protects the internal materials from external mechanical friction and chemical erosion. It uses high molecular polymer polytetrafluoroethylene (PTFE) with a thickness of 0.1-0.5 mm, and the surface texture of the protective layer is designed to be a micro-groove structure; Pressure sensing layer: It is located just below the protective layer and is made of a polymer composite material doped with carbon nanotubes (CNTs). It is used to sense external pressure changes and has a thickness of 0.2-0.8 mm. Liquid metal layer: Located below the pressure sensing layer, it is made of a gallium-based alloy that remains liquid at room temperature and changes its viscosity through an electric field. Its thickness is 0.5-2 mm; Base layer: The innermost layer, made of polyimide, serves as the basic support for the entire gasket, with a thickness of 1-3 mm.

4. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 3, characterized in that: The specific steps of the S200 gasket structure design are: S201, substrate pretreatment: using solvent isopropyl alcohol and ultrasonic cleaning equipment to thoroughly clean the substrate to remove surface impurities; S202, preparing a pressure sensing layer: dispersing CNTs in a solvent, N-methylpyrrolidone, uniformly dispersing the CNTs by ultrasonic treatment, uniformly coating the solution on the treated substrate, and heating and curing the coated sample to form a stable pressure sensing layer; S203, preparation of liquid metal layer: heating the gallium-based alloy until it is completely melted, using photolithography technology to produce micropores and microchannel structures, injecting molten liquid metal into the pre-prepared micropores and microchannels, and forming a stable liquid metal layer after the liquid metal is cooled; S204, preparing a protective layer: dissolving PTFE powder to form a uniform solution, coating the protective layer solution uniformly on the liquid metal layer, and heating and curing the coated sample to form a protective layer.

5. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 1, characterized in that: The specific steps of the S300 uniform mixing and dispersing are: S301, initial mixing: placing the liquid metal gallium-based alloy and the carbon nanotube-doped polymer composite material into a stirring container, setting the initial stirring speed to 100-200 rpm, starting stirring, and continuing for 5-10 minutes to achieve preliminary mixing of the materials; S302, gradually adjust the stirring parameters: gradually accelerate the stirring to 500-800 rpm, stir for 15-20 minutes, so that the materials are evenly mixed; S303, uniformity monitoring: during the stirring process, stop stirring every 5 minutes, use a sampling tool to extract mixture samples from different positions to check the uniformity of the mixture; S304, dispersion treatment: For agglomeration and uneven dispersion in the mixture, dispersion measures are taken, that is, high-speed shearing is used to cut the agglomerates through shear force to disperse them into smaller particles.

6. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 1, characterized in that: The specific steps of S400 are: S401, electrode plate installation: installing the electrode plates on both sides of the liquid metal layer, fixing the electrode plates with conductive glue, and adjusting the spacing and positions of the electrode plates so that they can form a uniform electric field distribution on the liquid metal layer; S402, voltage application and control: connect the variable voltage power supply and the electrode plate, apply the voltage, and monitor the changes of voltage and current in real time to ensure the stability of the power supply output. At the same time, use the electric field strength measuring instrument to monitor the electric field strength in the liquid metal layer to verify whether the expected electric field strength value is reached; S403, adjusting voltage: gradually adjusting the voltage and observing the change of the viscosity of the liquid metal; S404, viscosity adjustment mechanism: real-time monitoring of the viscosity change of the liquid metal under the action of the electric field, adjusting the magnitude and duration of the voltage according to the deviation, transmitting the signal of the pressure sensing layer to the power controller in real time, and realizing automatic adjustment of the voltage to accurately control the viscosity of the liquid metal; S405, integrated pressure sensing and viscosity regulation: The pressure sensing layer is combined with the viscosity regulation mechanism. When the pressure sensing layer detects pressure changes, the output voltage of the variable voltage power supply is automatically adjusted through the circuit, thereby achieving instant regulation of the viscosity of the liquid metal.

7. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 1, characterized in that: The specific steps of S500 are: S501, mold preparation: design and manufacture high-precision molds that match the shape and size of the gasket, thoroughly clean and pre-treat the molds, remove surface oil, impurities and oxide layers, and apply a release agent polytetrafluoroethylene coating on the inner surface of the mold; S502, mixture injection: slowly and evenly inject the mixture after adjusting the viscosity by external stimulation into the mold. The injection process should be continuous and stable, and the injection speed and pressure should be controlled; S503, cooling and solidification: placing the mold injected with the mixture into a cooling device, controlling the cooling speed to avoid excessive internal stress caused by excessive cooling. During the cooling process, continuously monitor the temperature distribution in the mold.

8. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 7, characterized in that: The S501 is coated with a release agent polytetrafluoroethylene coating on the inner surface of the mold with a thickness of 0.05 mm, and is slowly and evenly injected into the mold at a speed of 5-10 ml / s during the injection process of the S502 mixture. The injection pressure is controlled at 0.5-1 MPa, and the mold injected with the mixture is placed in a cold water bath at a temperature of 5-10°C for cooling. For a gasket with a thickness of 5 mm, the cooling time is about 30-60 minutes.

9. The method for preparing an integrated self-sealing liquid metal thermally conductive gasket according to claim 1, characterized in that: The S500 further includes: S504, temperature and pressure parameter monitoring: temperature sensors and pressure sensors are installed at the injection port, center and edge of the mold. The accuracy of the temperature sensor is ±0.5°C, and the accuracy of the pressure sensor is ±0.1MPa. The temperature and pressure changes during the cooling and curing process are monitored in real time. S505, demoulding and post-processing: After the gasket is completely cured, the molded gasket is taken out, and a preliminary appearance inspection is performed on the demoulded gasket to remove surface burrs and flash defects.

10. An application of an integrated self-sealing liquid metal thermally conductive gasket, characterized in that: The thermally conductive gasket is suitable for equipment that is frequently started and stopped, namely, bearings, gear boxes, hydraulic systems in industrial machinery, and key components of automobile engines and transmissions.

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