3D uniform-temperature plate radiator and manufacturing method thereof

Abstract

The invention discloses a 3D uniform-temperature plate radiator and a manufacturing method thereof, and the 3D uniform-temperature plate radiator comprises a uniform-temperature plate which comprises an upper plate and a lower plate, and the upper plate and the lower plate define a first cavity; the cooling structure comprises a cooling pond, a liquid storage pond, a first heat pipe group and a heat conducting sheet, the cooling pond is arranged at the bottom of the first cavity, a groove body is formed in the face, not in contact with the first cavity, of the cooling pond, the liquid storage pond is arranged in the groove body, one end of the first heat pipe group penetrates into the first cavity and is away from the cooling pond by a preset height, and the other end of the first heat pipe group is arranged in the groove body. The other end passes through the plurality of groups of heat-conducting fins; the microporous hydrophobic membrane is arranged on the side, provided with the tank body, of the cooling pool in a covering manner; and the semipermeable membrane is arranged at the contact position of the liquid storage tank and the cooling tank. According to the invention, the microporous hydrophobic film is combined with the cooling structure, so that the heat of the heating source can be uniformly transferred and dissipated, the local overheating phenomenon is prevented, and the uniformity and stability of heat dissipation are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of radiators, and in particular to a 3D temperature homogenizing plate radiator and a manufacturing method thereof. Background Art

[0002] With the development of high-tech, electronic components are getting smaller and smaller, but their power consumption is getting higher and higher. Once the temperature is too high, it will cause failure or even explosion. The role of the radiator is highlighted, especially with the development of AI technology. The demand for heat dissipation in data centers is increasing. The 3D temperature spreader radiator can meet the bottleneck needs of heat dissipation of high-power devices and temperature equalization in high heat flux density areas, and can be used for heat dissipation of data center servers.

[0003] Generally, a 3D temperature vapor chamber is composed of a heat pipe and a temperature vapor chamber. A heat dissipation circulation loop is realized through a capillary structure inside the temperature vapor chamber, and a working medium, that is, a coolant, is arranged in the capillary structure near the heat source. The coolant is transported from the heat source along the capillary structure to other locations through capillary action. In this loop, the coolant dissipates the heat of the heat source. However, due to the reflux of the coolant in the capillary structure, it accumulates at the heat source, causing local overheating.

[0004] To solve the above problems, an embodiment of the present invention provides a 3D vapor chamber heat sink, which aims to solve the problem of local overheating. Summary of the invention

[0005] The object of the present invention is to provide a 3D vapor chamber heat sink and a manufacturing method thereof to solve the problem of local overheating.

[0006] To achieve this object, the present invention adopts the following technical solutions: A 3D vapor chamber heat sink, the 3D vapor chamber heat sink comprising: A temperature equalizing plate, comprising an upper plate and a lower plate, wherein the upper plate and the lower plate enclose a first cavity; A cooling structure, comprising a cooling pool, a liquid storage pool, a first heat pipe group and a heat conducting sheet, wherein the cooling pool is arranged at the bottom of the first cavity, and a groove body is provided on a side not in contact with the first cavity, the liquid storage pool is arranged in the groove body, one end of the first heat pipe group penetrates into the first cavity and is at a preset height from the cooling pool, and the other end passes through a plurality of groups of heat conducting sheets; A microporous hydrophobic membrane is provided to cover one side of the cooling pool; A semipermeable membrane is arranged at a position where the liquid storage tank contacts the cooling tank.

[0007] Furthermore, the 3D vapor chamber heat sink also includes a condensation plate; The surface of the condensation plate is provided with a plurality of holes corresponding to the first heat pipe group, and the surface is covered with a hydrophilic coating; the condensation plate is fixed in the first cavity at a preset height from the cooling pool, and the side covered with the hydrophilic coating is arranged toward the cooling pool.

[0008] Furthermore, the cross section of the cooling pool is high on both sides and low in the middle.

[0009] Furthermore, the cooling structure also includes a heat sink; a second chamber is arranged in the heat sink; and a capillary structure is laid along the inner wall of the second chamber.

[0010] Furthermore, a liquid medium is provided in the capillary structure in the second chamber near the heat source.

[0011] Furthermore, the cooling structure also includes a second heat pipe group; the second heat pipe group is arranged at one end of the heat sink and is connected to the second chamber.

[0012] Furthermore, one end of the heat sink connected to the second heat pipe group and the second heat pipe group are both in contact with the temperature equalizing plate.

[0013] Furthermore, inner walls of the first heat pipe group and the second heat pipe group are both provided with capillary structures.

[0014] A method for manufacturing a 3D vapor chamber heat sink is also proposed, for manufacturing the 3D vapor chamber heat sink as claimed in any one of claims 1 to 8, comprising: S1, after diffusion welding the upper plate and the lower plate, a first cavity is formed to obtain a temperature balancing plate; S2, sintering the adapted copper mesh and the heat pipe to form a capillary structure; S3, select a metal with excellent thermal conductivity as a heat pipe, the inner wall of the heat pipe is sintered with the capillary structure in step S2, and obtain a first heat pipe group; make a cooling pool at the bottom of the first cavity of the temperature homogenizing plate, open a groove body on the side of the cooling pool that is not in contact with the first cavity, and then set a liquid storage tank in the groove body; insert one end of at least four heat pipes into the first cavity and at a preset height from the liquid storage tank, and pass the other end through multiple groups of heat conducting sheets, and fix them by welding or other suitable connection methods; S4, using polytetrafluoroethylene as raw material and using electrospinning technology to prepare microporous hydrophobic membrane; S5. A plurality of holes corresponding to and connected to the first heat pipe group are arranged on the surface of the condensing plate, and the surface is covered with a hydrophilic coating. The condensing plate is fixed in the first cavity at a preset height from the cooling pool, and the surface covered with the hydrophilic coating is arranged toward the cooling pool; S6. Assemble the prepared cooling assembly, microporous hydrophobic membrane, semipermeable membrane, condensation plate and temperature equalizing plate to ensure that all components are tightly connected without looseness or leakage; S7. Fill the cooling pool with helium through the reserved liquid injection port or other channels to detect whether the entire 3D temperature dispersion plate radiator has side leakage; S8. Inject a proper amount of liquid working medium into the first cavity through the liquid injection port, then evacuate the first cavity to remove impurities such as air and moisture inside, and finally weld the liquid injection port to keep the first cavity sealed, thereby completing the production of the 3D temperature vapor chamber radiator.

[0015] Furthermore, the diffusion welding in step S1 is diffusion welding without an intermediate layer, the diffusion welding temperature is 700-950° C., the welding time is 3-9 hours, and the welding pressure is 0.2-0.9 ; The sintering temperature is 150-300° C., and the welding time is 2-4.5 hours.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The first cavity is formed by the upper plate and the lower plate, providing space for the circulation of coolant and heat transfer, achieving efficient heat distribution and avoiding local overheating, while meeting the requirements of miniaturization and thinness of equipment; the cooling pool, liquid storage pool, first heat pipe group and heat conducting sheet work together to optimize the circulation path of coolant and accelerate heat transfer, and the layout is flexible to adapt to different heat dissipation requirements; the microporous hydrophobic membrane is cleverly used to achieve gas-liquid separation and prevent coolant leakage, and operate under mild conditions; the semi-permeable membrane accurately controls the flow of coolant and maintains a stable heat dissipation cycle. In general, the heat dissipation effect is greatly improved through the cooperation of various mechanisms. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] 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 description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.

[0019] Figure 1 It is a structural schematic diagram of an embodiment of a 3D vapor chamber heat sink of the present invention; Figure 2A cross-sectional view of a vapor chamber of a 3D vapor chamber heat sink according to an embodiment of the present invention; Figure 3 A cross-sectional view of a vapor chamber of a 3D vapor chamber heat sink according to an embodiment of the present invention; Figure 4 The figure is a flow chart of an embodiment of a method for manufacturing a 3D vapor chamber heat sink of the present invention.

[0020] Illustrations: 100, temperature equalizing plate; 200, cooling structure; 300, microporous hydrophobic membrane; 400, semipermeable membrane; 500, condensation plate; 110, upper plate; 120, lower plate; 210, cooling pool; 220, liquid storage tank; 230, first heat pipe group; 240, heat conducting sheet; 250, heat sink; 260, second heat pipe group. DETAILED DESCRIPTION

[0021] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0022] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time.

[0023] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0024] like Figures 1 to 4 As shown, Figure 1 It is a structural schematic diagram of an embodiment of a 3D vapor chamber heat sink of the present invention; Figure 2 A cross-sectional view of a vapor chamber of a 3D vapor chamber heat sink according to an embodiment of the present invention; Figure 3 A cross-sectional view of a vapor chamber of a 3D vapor chamber heat sink according to an embodiment of the present invention; Figure 4 The figure is a flow chart of an embodiment of a method for manufacturing a 3D vapor chamber heat sink of the present invention.

[0025] Embodiment 1: An embodiment of the present invention provides a 3D temperature vapor chamber heat sink. By combining a microporous hydrophobic membrane 300 and a heat dissipation system, the coolant in the cooling pool 210 can absorb a large amount of heat and release the heat through the heat dissipation system. While dissipating heat efficiently and stably, it can effectively reduce the temperature of the equipment during operation, avoid performance degradation of the equipment due to long-term high-temperature operation, accelerated aging of electronic components, and other problems, thereby extending the service life of the equipment and reducing the maintenance and replacement costs of the equipment.

[0026] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a 3D vapor chamber heat sink, and the 3D vapor chamber heat sink comprises: The temperature equalizing plate 100 includes an upper plate 110 and a lower plate 120, wherein the upper plate 110 and the lower plate 120 enclose a first cavity (not marked in the figure); the cooling structure 200 includes a cooling pool 210, a liquid storage pool 220, a first heat pipe group 230 and a heat conductive sheet 240, wherein the cooling pool 210 is arranged at the bottom of the first cavity, and a groove is provided on a side not in contact with the first cavity, the liquid storage pool 220 is arranged in the groove, one end of the first heat pipe group 230 penetrates into the first cavity and is at a preset height from the cooling pool 210, and the other end passes through a plurality of groups of heat conductive sheets 240; a microporous hydrophobic membrane 300 covers a side of the cooling pool 210 where the groove is provided; and a semipermeable membrane 400 is arranged at a position where the liquid storage pool 220 and the cooling pool 210 are in contact.

[0027] Furthermore, the cross section of the cooling pool 210 is high at both sides and low in the middle. It should be noted that the housing formed by the upper plate 110 and the lower plate 120 has a cavity inside, that is, the first cavity, and a mounting plate is fixedly provided at the connection end between the lower plate 120 and the upper plate 110, and the microporous hydrophobic membrane 300 is mounted on the mounting plate, and a cooling pool 210 is formed between the mounting plate and the bottom of the first cavity for placing a coolant for heat dissipation circulation. The mounting plate is preferably a plate with a V-shaped cross-section, which is convenient for collecting the liquefied coolant. The liquid reservoir 220 is installed at the V-shaped structure of the mounting plate, which is also the central position of the mounting plate. The semipermeable membrane 400 is arranged at the bottom of the liquid reservoir 220. The coolant needs to be injected into the cooling pool 210 and the liquid reservoir 220 in advance and needs to be filled. The top of the liquid reservoir 220 is not capped, and the liquefied coolant will continuously converge in the liquid reservoir 220 under the action of gravity. At the same time, it should be noted that the cooling pool 210 filled with coolant continuously absorbs heat from the heat source, thereby turning into gas and leaving the cooling pool 210 through the microporous hydrophobic membrane 300, so that the coolant in the cooling pool 210 becomes less, and the coolant in the liquid reservoir 220 enters the cooling pool 210 through the semipermeable membrane 400 as a supplementary coolant to prevent the coolant from evaporating completely during use, causing the entire radiator to malfunction. The angle of the V-shaped structure is preferably an obtuse angle such as 150°, 160° and 170°. It should be noted that the volume of the 3D temperature vapor chamber heat sink should not be too large.

[0028] It should also be added that the microporous hydrophobic membrane 300 described here uses the technology of membrane distillation. The basic principle of membrane distillation is: due to the microporosity and hydrophobicity of the membrane, under the action of surface tension, the liquid on both sides will not reach the other side through the membrane pores; the average molecular free path of the steam is much larger than the average pore size of the microporous membrane, so it can pass through the membrane pores; the liquid on both sides of the membrane has different vapor pressures due to the temperature difference (the vapor pressure difference can also be caused by other factors), the hot side liquid is continuously vaporized at the membrane interface, and the steam molecules flow through the membrane pores to the cold side under the drive of the vapor pressure difference, and finally condense on the cold side. The membrane distillation process is very similar to the evaporation-transfer-condensation process of conventional distillation, and its outstanding advantage is that it can be operated at normal pressure and slightly higher than room temperature. The microporous hydrophobic membrane 300 must be resistant to high temperature and corrosion. In addition, if the other end of the membrane, when the gas passes through the microporous hydrophobic membrane 300, heat exchange occurs with the hydrophobic membrane or the surrounding environment with a lower temperature, causing the gas temperature to drop below the dew point temperature, the steam will condense, thereby changing from gas to liquid. For example, when the ambient temperature is low, after a large amount of steam passes through the hydrophobic membrane, it is very likely that part of it will condense into small droplets, and then slowly gather in the liquid reservoir 220 under the action of gravity in the V-shaped structure of the mounting plate, and the coolant in the liquid reservoir 220 will not exceed its volume, and will continue to enter the cooling pool 210 under the pressure difference and gravity as the coolant in the cooling pool 210 decreases. Secondly, the temperature of the gas passing through the membrane is higher than its dew point temperature. In the process of passing through the microporous hydrophobic membrane 300, there is no sufficient heat exchange to reduce the temperature to below the dew point, so the gas will still remain in a gaseous state after passing through the hydrophobic membrane. For example, in some high temperature and low pressure environments, steam has a high energy, and when passing through the hydrophobic membrane, the environmental conditions are not sufficient to condense it, so it will exist in a gaseous form.

[0029] Furthermore, the capillary structure (not shown in the figure) can absorb water. The capillary structure is provided in the first heat pipe group 230 to increase the contact area between the coolant and the cooling structure 200, and release heat to the first heat pipe group 230. It should be noted that the first heat pipe group 230 is composed of at least one hollow heat pipe, and one end of the heat pipe penetrates into the first cavity and is at a preset height from the cooling pool 210, and the other end passes through multiple groups of heat conductive sheets 240. Through this structure, the vaporized coolant enters the first heat pipe group 230, and the heat of the vaporized coolant is transferred to the first heat pipe group 230 and to the heat conductive sheets 240, and then released to the surrounding air.

[0030] Furthermore, a fan is provided, and the fan buckle is provided on the tower group composed of the heat conducting sheet 240, so that the heat of the heat conducting sheet 240 is efficiently released into the air.

[0031] Furthermore, the 3D vapor chamber heat sink further includes a condenser plate 500; a plurality of holes corresponding to and connected to the first heat pipe group 230 are arranged on the surface of the condenser plate 500, and the surface is covered with a hydrophilic coating (not shown in the figure); the condenser plate 500 is fixed in the first cavity at a preset height from the cooling pool 210, and the side covered with the hydrophilic coating is arranged toward the cooling pool 210. It should be noted that the distance between the condenser plate 500 fixed in the first cavity and the nearest point of the cooling pool 210 is a preset height, preferably 1 mm and 2 mm.

[0032] The 3D temperature-averaging plate heat sink solution works in coordination with various components. The cooling pool 210 absorbs heat from the heat source, the coolant vaporizes, and the steam passes through the microporous hydrophobic membrane 300 and is transferred to the heat conductive sheet 240 through the first heat pipe group 230, thereby increasing the heat dissipation area and accelerating the heat dissipation to the air. The hydrophilic coating on the surface of the condensation plate 500 helps the steam to condense quickly and improve the heat dissipation efficiency. The hole design connected to the first heat pipe group 230 optimizes the heat transfer path. Secondly, the cooling pool 210 and the liquid storage tank 220 cooperate with the semi-permeable membrane 400 to automatically adjust the coolant replenishment according to the coolant state and pressure difference, ensuring the stability of the coolant amount in the cooling pool 210 and maintaining the normal operation of the heat dissipation cycle. The parameters of each component can be adjusted according to actual needs, such as preset height, angle, etc., to improve the adaptability to different heat sources and equipment.

[0033] Embodiment 2: This embodiment is a cooling structure 200 further supplementing the first embodiment. Figure 3 As shown, a cross-sectional view of a heat spreader 100 of an embodiment of a 3D heat spreader radiator of the present invention is shown, the cooling structure 200 further includes a heat sink 250; a second chamber (not marked in the figure) is arranged in the heat sink 250; a capillary structure is laid along the inner wall of the second chamber; a liquid medium is arranged in the capillary structure near the heat source in the second chamber; the cooling structure 200 further includes a second heat pipe group 260; the second heat pipe group 260 is arranged at one end of the heat sink 250 and communicated with the second chamber. The end of the heat sink 250 connected to the second heat pipe group 260 and the second heat pipe group 260 are both in contact with the heat spreader 100.

[0034] It should be noted that the first heat pipe group 230, the inner wall of the second chamber and the capillary structure of the second heat pipe group 260 are powder sintered bodies, preferably metal powder sintered bodies, among which copper powder sintered bodies are the best. In another embodiment, they can also be metal woven meshes, composite metal meshes (powder sintered bodies plus metal woven meshes), etc. It should also be added that in order to better achieve the contact between the temperature averaging plate 100 and the welded body formed by welding the second heat pipe group 260 and the heat dissipation plate 250, the bottom of the temperature averaging plate 100 is provided with a protruding structure adapted to the second heat pipe group 260, which can achieve a larger contact area and is more conducive to heat dissipation.

[0035] In summary, when the second heat pipe group 260 is joined to the heat sink 250, the opening flange of the heat sink 250 and the flared end of the heat pipe of the second heat pipe group 260 are interfered with to form a tight fit, thereby connecting the heat pipe and the first cavity, and the tight fit effect is good, the finished product yield is high, the durability is good, the processing cost is low, the weight is light, and the interference fit effect is better than welding, and the inner wall remains smooth, because during the welding process, due to the filling and high temperature of the welding material, it is easy to form uneven structures such as weld nodules and burrs on the inner wall, and the interference fit is achieved by mechanical extrusion between the components, and the inner wall can remain smooth. For the circulation of the working fluid inside the temperature-averaging plate radiator, the smooth inner wall can reduce the resistance to fluid flow, further increase the circulation efficiency of the working fluid in the two chambers, and make the coolant flow smoother in the system, which is more conducive to the long-term stable operation of the heat dissipation system than welding. Secondly, it is only an interference fit, which is convenient for disassembly and assembly, replacement and maintenance, and is suitable for different scenarios. The interference fit can be used for disassembly and assembly to improve the cooling effect. The single temperature equalizing plate 100 can provide a certain cooling effect. When the cooling effect of the single temperature equalizing plate 100 is not enough, the heat sink 250 and the second heat pipe group 260 can be assembled to greatly improve the cooling effect.

[0036] Furthermore, the present embodiment provides a multi-stage heat dissipation system, in which the second heat pipe group 260 is welded to the heat sink 250 to form a primary heat dissipation, directly contacting the heat source, and transferring the heat to various parts of the heat sink 250 through the internal capillary structure, wherein the part in contact with the temperature equalizing plate 100 transfers the heat to the temperature equalizing plate 100, and because of its large contact area, it can absorb a large amount of heat, and then the heat reaches the secondary heat dissipation composed of the temperature equalizing plate and the heat dissipation structure, the heat first heats the coolant in the cooling pool 210, and then vaporizes the coolant, and then transmits the heat to the heat conductive sheet 240 one by one through the first heat pipe group 230 and its capillary structure, and then releases it into the air, and then through the fan, the heat release amount is greatly increased.

[0037] The newly added heat sink 250, the second chamber and the second heat pipe group 260 work together with the original cooling structure 200 to further expand the heat dissipation path. The liquid medium absorbs heat and evaporates under the action of the capillary structure, and transfers the heat to the temperature equalizing plate 100 through the second heat pipe group 260, which works together with the original first heat pipe group 230 and other structures to make the heat dissipation more efficient and comprehensive, further reduce the temperature of the heat source, and improve the overall heat dissipation effect. A raised structure adapted to the second heat pipe group 260 is set at the bottom of the temperature equalizing plate 100, which increases the contact area and is more conducive to the transfer of heat from the second heat pipe group 260 to the temperature equalizing plate 100, reducing thermal resistance and accelerating heat conduction, thereby improving the heat transfer efficiency of the entire radiator.

[0038] Embodiment three: like Figure 4 FIG. 1 is a flow chart of an embodiment of a method for manufacturing a 3D vapor chamber heat sink of the present invention. As shown in the figure, the present invention proposes a method for manufacturing a 3D vapor chamber heat sink, including the following steps S1 to S8: S1, manufacturing a temperature averaging plate, wherein the upper plate and the lower plate are diffusion welded to form the first cavity and obtain a temperature averaging plate; S2, sintering the capillary structure, sintering the matching copper mesh and the heat pipe to form a capillary structure; S3, manufacturing a cooling structure, selecting a metal with excellent thermal conductivity as a heat pipe, sintering the inner wall of the heat pipe with the capillary structure in step S2, and obtaining a first heat pipe group; manufacturing a cooling pool at the bottom of the first cavity of the temperature homogenizing plate, opening a groove body on the side of the cooling pool that is not in contact with the first cavity, and then setting a liquid storage tank in the groove body; inserting one end of at least four heat pipes into the first cavity at a preset height from the liquid storage tank, and passing the other end through multiple groups of heat conducting sheets, and fixing them by welding or other suitable connection methods; S4, preparation of microporous hydrophobic membrane, using polytetrafluoroethylene as raw material, and using electrospinning technology to prepare microporous hydrophobic membrane; S5. Making a condensation plate, setting a plurality of holes corresponding to and connected to the first heat pipe group on the surface of the condensation plate, and covering the surface with a hydrophilic coating, fixing the condensation plate in the first cavity at a preset height from the cooling pool, and setting the surface covered with the hydrophilic coating toward the cooling pool; S6. Assemble the prepared cooling assembly, microporous hydrophobic membrane, semipermeable membrane, condensation plate and other components with the temperature equalization plate to ensure that all components are tightly connected without looseness or leakage; S7, side leakage detection, fill the cooling pool with helium through the reserved injection port or other channels to detect whether the entire 3D temperature plate radiator has side leakage; S8. Inject a proper amount of liquid working medium into the first cavity through the liquid injection port, then evacuate the first cavity to remove impurities such as air and moisture inside, and finally weld the liquid injection port to keep the first cavity sealed, thereby completing the production of the 3D temperature vapor chamber radiator.

[0039] It should be noted that the capillary structure is a powder sintered body, preferably a metal powder sintered body, among which copper powder sintered body is the best. In another embodiment, it can also be a metal woven mesh, a composite metal mesh (powder sintered body plus a metal woven mesh), etc.

[0040] Furthermore, the pore size, hydrophobicity, high temperature resistance, etc. of the microporous hydrophobic membrane 300 need to be precisely controlled, otherwise the pore size may be too large, causing the coolant to evaporate prematurely, or the pore size may be too small, causing the coolant to be unable to flow, affecting the efficiency of thermal management. It is more preferred that the material used is polytetrafluoroethylene (PTFE), which has good high temperature resistance and corrosion resistance. The hot side fluid (coolant, which is also a liquid working fluid) is heated by the heat source, and the temperature rises, forming a vapor pressure difference on both sides of the microporous hydrophobic membrane 300. A high vapor pressure is formed on the side close to the heat source, and the working fluid evaporates, thereby forming a low-pressure side on the other side. The evaporated working fluid passes through the microporous hydrophobic membrane 300 into the first cavity, and then enters the tube of the first heat pipe group 230, thereby playing a role in phase change heat transfer.

[0041] It should be noted that the selection of a smaller pore size for the microporous hydrophobic membrane 300 means that the thin layer area formed by the liquid on the surface of the membrane is smaller, which may result in a reduction in the surface area of ​​the liquid in contact with external gas (such as air or vacuum), which will limit the evaporation rate of the liquid. On the contrary, a larger pore size can increase the contact area between the liquid and the external gas, thereby accelerating the evaporation process. The pore size of the microporous hydrophobic membrane 300 affects whether the pores are connected and the density of the pore network. A larger pore size may make the pores of the membrane more connected, allowing the gas to penetrate and flow more quickly, thereby facilitating the evaporation of the coolant. For a membrane with a smaller pore size, the pores may not be easily connected, forming closed water droplets or droplets, thereby reducing the evaporation area and thus extending the evaporation time. The pore size of the microporous hydrophobic membrane 300 affects whether the pores are connected and the density of the pore network. A larger pore size makes the pores of the membrane more connected, allowing the gas to penetrate and flow more quickly, thereby facilitating the evaporation of the coolant, while for a membrane with a smaller pore size, the pores are not easily connected, forming closed water droplets or droplets, thereby reducing the evaporation area and thus extending the evaporation time. As a more preferred embodiment, the microporous hydrophobic membrane 300 uses an average membrane pore diameter of 0.1 mm, a porosity of 70%, and a membrane thickness of 0.2 mm, which helps the 3D temperature vapor chamber heat sink to improve cooling efficiency, stability and durability. Through appropriate pore size and porosity design, the membrane can effectively promote liquid flow, increase evaporation rate, avoid liquid retention and reduce condensation, thereby enhancing the heat dissipation performance and the long-term reliability of the system.

[0042] Furthermore, the diffusion welding in step S1 is diffusion welding without an intermediate layer, the diffusion welding temperature is 700-950° C., the welding time is 3-9 hours, and the welding pressure is 0.2-0.9 ; The sintering temperature is 150-300°C, and the welding time is 2-4.5h. It should be noted that the connection between the upper plate 110 and the lower plate 120 after diffusion welding is fused with each other without seams. The diffusion welding of metals is completed by atomic diffusion of the contact surface of the metals to be welded. The weldment has high precision and small deformation. Since the pressure applied during welding is small, the workpiece is mostly heated as a whole and cooled with the furnace. Therefore, the overall plastic deformation of the temperature balancing plate 100 after welding is very small. The composition and performance of the welded joint are similar to those of the upper plate 110 and the lower plate 120. It is difficult to see the joint surface of the upper plate 110 and the lower plate 120 even with a microscope, so that the upper plate 110 and the lower plate 120 can be regarded as a whole after welding, effectively ensuring the sealing performance of the first cavity.

[0043] The sintering temperature is 150-300°C, and the welding time is 2-4.5h. The metal powder (copper powder is used in this embodiment) will not melt during sintering, but will only be fixedly connected to the carrier after sintering, and will not melt the carrier. The carrier refers to the upper plate 110, the lower plate 120, the first heat pipe group 230, the second heat pipe group 260 and other mother bodies that need to be sintered in this embodiment.

[0044] The coolant, that is, the liquid medium, is selected from one of pure water, salt water, diethyl ether or acetone. In the first, second and third embodiments, the volume of the liquid medium is preferably 1 / 3 of the volume of the first cavity, the pressure in the first cavity and the second cavity is less than 0.5 atmospheres, the liquid medium is pure water, and the air pressure in the first cavity is less than the atmospheric pressure, so that the boiling point of pure water is low, and it evaporates into gas without very high temperature (the boiling point of water is 100°C under standard atmospheric pressure), taking away heat, and having high cost performance. Pure water has a large specific heat capacity, which means that it can absorb more heat while its own temperature rise is relatively small, and through the circulation flow in the temperature averaging plate 100, the heat is transferred to other parts for heat dissipation, thereby ensuring that the temperature at the heat source is within a reasonable range. Secondly, pure water has stable chemical properties, is not easy to react chemically with common materials (such as metals, plastics, etc.) in the temperature averaging plate, will not damage the structure and performance of the temperature averaging plate 100, and ensures the long-term stability and reliability of the radiator. This means that during the design and manufacturing process of the radiator, there is no need to consider too much about the compatibility of materials and liquid media, reducing the difficulty of design and production.

[0045] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A 3D vapor chamber heat sink, characterized in that: The 3D vapor chamber heat sink comprises: A temperature equalizing plate, comprising an upper plate and a lower plate, wherein the upper plate and the lower plate enclose a first cavity; A cooling structure, comprising a cooling pool, a liquid storage pool, a first heat pipe group and a heat conducting sheet, wherein the cooling pool is arranged at the bottom of the first cavity, and a groove body is provided on a side not in contact with the first cavity, the liquid storage pool is arranged in the groove body, one end of the first heat pipe group penetrates into the first cavity and is at a preset height from the cooling pool, and the other end passes through a plurality of groups of heat conducting sheets; A microporous hydrophobic membrane is provided to cover one side of the cooling pool; A semipermeable membrane is arranged at a position where the liquid storage tank contacts the cooling tank.

2. The 3D vapor chamber heat sink according to claim 1, characterized in that: The 3D vapor chamber heat sink also includes a condensation plate; The surface of the condensing plate is provided with a plurality of holes corresponding to and connected with the first heat pipe groups, and the surface is covered with a hydrophilic coating; The condensation plate is fixed in the first cavity at a preset height from the cooling pool, and a surface covered with the hydrophilic coating is arranged toward the cooling pool.

3. The 3D vapor chamber heat sink according to claim 1, characterized in that: The cross section of the cooling pool is high at both sides and low in the middle.

4. The 3D vapor chamber heat sink according to claim 1, characterized in that: The cooling structure also includes a heat sink; A second chamber is provided in the heat dissipation plate; A capillary structure is laid along the inner wall of the second chamber.

5. The 3D vapor chamber heat sink according to claim 4, characterized in that: Liquid medium is arranged in the capillary structure near the heat source in the second chamber.

6. The 3D vapor chamber heat sink according to claim 5, characterized in that: The cooling structure also includes a second heat pipe group; The second heat pipe group is disposed at one end of the heat dissipation plate and communicated with the second chamber.

7. The 3D vapor chamber heat sink according to claim 6, characterized in that: One end of the heat sink connected to the second heat pipe group and the second heat pipe group are both in contact with the temperature equalizing plate.

8. The 3D vapor chamber heat sink according to claim 7, characterized in that: The inner walls of the first heat pipe group and the second heat pipe group are both provided with capillary structures.

9. A method for manufacturing a 3D temperature-equalizing plate heat sink, characterized in that: A 3D vapor chamber heat sink for manufacturing any one of claims 1 to 8, comprising: S1, after diffusion welding the upper plate and the lower plate, a first cavity is formed to obtain a temperature balancing plate; S2, sintering the adapted copper mesh and the heat pipe to form a capillary structure; S3, select a metal with excellent thermal conductivity as a heat pipe, the inner wall of the heat pipe is sintered with the capillary structure in step S2, and obtain a first heat pipe group; make a cooling pool at the bottom of the first cavity of the temperature homogenizing plate, open a groove body on the side of the cooling pool that is not in contact with the first cavity, and then set a liquid storage tank in the groove body; insert one end of at least four heat pipes into the first cavity and at a preset height from the liquid storage tank, and pass the other end through multiple groups of heat conducting sheets, and fix them by welding or other suitable connection methods; S4, using polytetrafluoroethylene as raw material and using electrospinning technology to prepare microporous hydrophobic membrane; S5. A plurality of holes corresponding to and connected to the first heat pipe group are arranged on the surface of the condensing plate, and the surface is covered with a hydrophilic coating. The condensing plate is fixed in the first cavity at a preset height from the cooling pool, and the surface covered with the hydrophilic coating is arranged toward the cooling pool; S6. Assemble the prepared cooling assembly, microporous hydrophobic membrane, semipermeable membrane, condensation plate and temperature equalizing plate to ensure that all components are tightly connected without looseness or leakage; S7. Fill the cooling pool with helium through the reserved liquid injection port or other channels to detect whether the entire 3D temperature dispersion plate radiator has side leakage; S8. Inject a proper amount of liquid working medium into the first cavity through the liquid injection port, then evacuate the first cavity to remove impurities such as air and moisture inside, and finally weld the liquid injection port to keep the first cavity sealed, thereby completing the production of the 3D temperature vapor chamber radiator.

10. The method for manufacturing a 3D vapor chamber heat sink according to claim 9, characterized in that: The diffusion welding in step S1 is diffusion welding without an intermediate layer, the diffusion welding temperature is 700-950°C, the welding time is 3-9h, and the welding pressure is 0.2-0.9 ; The sintering temperature is 150-300° C., and the welding time is 2-4.5 hours.

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