A thin curved surface heat sink and its manufacturing process

Abstract

The present application relates to a thin curved heat spreader and its manufacturing process, belonging to the field of heat transfer devices. The heat spreader includes a curved bottom plate, a curved cover plate, a first capillary structure and a second capillary structure. The curved bottom plate is provided with a heat spreader structure receiving groove, a support rib group is provided in the heat spreader structure receiving groove, the support rib group includes at least two support ribs, and the support ribs are provided with steam grooves that penetrate both sides of the support ribs. The first capillary structure is provided in the heat spreader structure receiving groove and is located above the support rib group. The second capillary structure is provided between the support ribs inside the support rib group. The curved cover plate is fixed on the curved bottom plate and covers the notch of the heat spreader structure receiving groove to form a heat spreader structure cavity isolated from the outside world. The heat spreader structure cavity is filled with a heat spreader medium. It has the advantages of thinness, strong curved surface adaptability, and good heat spreader effect, and can be widely used in aerospace and other fields.

Description

Technical Field

[0001] The present application relates to the field of heat transfer and heat dissipation devices, and in particular to a thin curved surface vapor chamber. In addition, the present application also relates to a manufacturing process of the thin curved surface vapor chamber. Background Art

[0002] With the development of science and technology, electronic equipment is widely used in all walks of life. Electronic equipment refers to equipment composed of integrated circuits, transistors, electron tubes and other electronic components as the core. Electronic equipment can collect, transmit, process and control information, which greatly improves the automation and information level of production and living facilities. With the improvement of the functions of electronic equipment, its working power is getting higher and higher, and the heat generated during operation is also increasing. The accumulation of heat will cause the operating temperature of electronic equipment to increase, and electronic components usually have operating temperature requirements. When the temperature exceeds the operating temperature limit of the electronic components, it will cause confusion in the operation of the electronic equipment and even cause the electronic components to burn. For this reason, a heat transfer device is usually set in the electronic equipment to absorb and transfer the heat generated by the electronic equipment to ensure that the electronic components work at a suitable temperature level.

[0003] A vapor chamber is a vacuum chamber with a microstructured inner wall, which is filled with a vapor chamber medium. The vapor chamber is usually set on the surface of electronic equipment or electronic components. The heat generated by the electronic components causes the vapor chamber medium to absorb heat and vaporize in the vacuum chamber. The vapor chamber medium flows to the low-temperature area of ​​the vapor chamber medium, where it releases heat and condenses, quickly transferring the heat generated by the electronic components to the low-temperature area for dissipation. It has the advantages of large heat transfer and fast heat transfer speed, and is widely used in the heat dissipation of high-power high-end electronic equipment.

[0004] In the field of aerospace, due to the need for remote communication and precise control, the electronic equipment used is becoming more and more complex, and the power of the electronic equipment used is also getting higher and higher. Vapor chambers have also been widely used in the field of aerospace. However, due to space limitations, the density of electronic equipment is very high, and the space for setting up vapor chambers in electronic equipment is very limited. Moreover, in order to set up more electronic equipment in a limited and narrow space, electronic components are usually set in different spatial planes and spatial curved surfaces. This puts forward the requirements of thinness and bending of the vapor chamber.

[0005] Most of the existing thin heat spreaders are planar structures, which are difficult to meet the heat dissipation needs on spatial curved surfaces. The Chinese patent application with publication number CN112222236A discloses a bendable ultra-thin heat spreader that can be bent along a bending mechanism, but it can only be used for a spatial plane with a fixed bending direction and cannot meet the heat dissipation needs of spatial curved surfaces. The Chinese patent application with publication number CN107764116A discloses an ultra-thin flexible heat spreader, which uses flexible materials to make the upper shell and the lower shell, so that it can be used for the heat spread of flexible and curved electronic components. However, it is difficult for the upper shell and the lower shell made of flexible materials to take into account flexibility and thermal conductivity at the same time, and the liquid wick set inside it is also difficult to support the bending of the heat spreader. This makes it difficult for the shell of the flexible heat spreader to fit tightly with the electronic components, especially when the electronic components are set on a conical surface or a quadratic surface, which affects the heat spread effect of the heat spreader. Summary of the invention

[0006] In order to improve the heat transfer effect of a heat spreader on a curved structure device, the present application provides a thin curved heat spreader and a manufacturing process thereof.

[0007] The thin curved vapor chamber provided in this application adopts the following technical solution:

[0008] A thin curved heat spreader, comprising a curved bottom plate, a curved cover plate, a first capillary structure and a second capillary structure; a heat spreader structure accommodating groove is provided on the curved bottom plate, a support rib group is provided in the heat spreader structure accommodating groove, the support rib group comprises at least two support ribs, and a steam groove penetrating both sides of the support rib is provided on the support rib, the first capillary structure is arranged in the heat spreader structure accommodating groove and is located above the support rib group, the second capillary structure is arranged between the support ribs inside the support rib group, the curved cover plate is fixed on the curved bottom plate and covers the notch of the heat spreader structure accommodating groove, so as to form a heat spreader structure cavity isolated from the outside, and the heat spreader structure cavity is filled with a heat spreader medium.

[0009] By adopting the above technical scheme, by using a curved bottom plate and a curved cover plate arranged in a set curved shape, the heat spreader can be closely fitted with the electronic components arranged on the set spatial curved surface, thereby ensuring efficient and reliable heat transfer between the electronic components and the curved bottom plate; by using a support rib group arranged in the heat spreader structure accommodating groove, a larger steam channel can be formed between the first capillary structure and the curved bottom plate, which is conducive to the smooth flow of the heat spreader steam between different temperature areas inside the heat spreader; by using a second capillary structure arranged between adjacent support ribs in the support rib group and a steam groove arranged on the support rib, another circulation path is provided for the heat spreader and its steam, which can further improve the flow performance of the heat spreader and its steam and improve the heat spreader effect.

[0010] In a specific possible implementation scheme, the curved bottom plate is configured as a cylindrical surface, a conical surface, a quadratic surface or a combination thereof, and the supporting rib group is arranged along the generatrix direction of the curved surface.

[0011] By adopting the above technical scheme, the curved bottom plate formed by a cylindrical surface, a conical surface, a quadratic surface or a combination thereof can correspond to electronic components on a variety of different spatial curved surfaces, so that the two fit closely, thereby ensuring efficient and reliable heat transfer between the electronic components and the curved bottom plate; by utilizing a support rib group arranged along the generatrix direction of the curved surface, it is possible to ensure that the support ribs are arranged in a straight line shape, thereby simplifying the arrangement of the support ribs, improving the structural stability of the support ribs, ensuring the unobstructed space for the second capillary structure between the support ribs, and ensuring the heat equalization effect of the heat spreader.

[0012] In a specific possible implementation scheme, a plurality of support rib groups are provided, the width of each support rib inside the support rib group is 1-5 mm, and the spacing between adjacent support ribs is 3-10 mm.

[0013] By adopting the above technical solution, using a support rib width of 1-5mm and a support rib spacing of 3-10mm, it is possible to provide reliable support for the second capillary structure while ensuring the bending performance of the curved bottom plate and the ability of the second capillary structure to guide the flow of liquid-phase homogenizing working fluid.

[0014] In a specific possible implementation manner, the first capillary structure is a metal woven mesh, and the sum of the thickness of the first capillary structure and the height of the supporting ribs is equal to the depth of the heat-saturating structure receiving groove.

[0015] By adopting the above technical solution and using a metal woven mesh as the first capillary structure, the first capillary structure can form effective capillary channels in different directions of the curved surface, thereby improving the flow capacity of the liquid-phase heat-equalizing medium in different directions of the curved surface; by setting the sum of the thickness of the first capillary structure and the height of the supporting ribs equal to the depth of the heat-equalizing structure accommodating groove, the supporting ribs can be used to support the first capillary structure and the curved cover plate, thereby ensuring the smooth flow of the steam channel below the first capillary structure and the stability of the structural morphology of the curved cover plate.

[0016] In a specific embodiment, the first capillary structure is a metal woven mesh with a mesh number of not less than 200 meshes.

[0017] By adopting the above technical solution and using a metal woven mesh with a mesh size of not less than 200 as the first capillary structure, the capillary channels inside the first capillary structure are more abundant, thereby ensuring the smooth flow of the liquid phase heat-homogenizing medium inside the first capillary structure.

[0018] In a specific embodiment, the second capillary structure is a porous metal material or a metal braided wire, and the porous metal material is at least one of foam copper, porous aluminum, and porous nickel.

[0019] By adopting the above technical solution and using porous metal material or metal braided wire as the second capillary structure, the abundant pores and gaps inside the porous metal material or metal braided wire can be utilized to form more capillary channels, thereby improving the flow performance of the liquid phase heat-homogenizing medium inside the second capillary structure.

[0020] In a specific implementation scheme, the length of the support rib group is smaller than the length of the heat-averaging structure accommodating groove in the same direction, the length of the second capillary structure is not greater than the length of the support rib group, the width of the steam groove is 0.5-3mm, and the depth is the same as the height of the support rib.

[0021] By adopting the above technical solution, by using a support rib group length that is smaller than the length of the heat equalizing structure accommodating groove, a gap can be formed between the two ends of the support rib group and the side walls of the heat equalizing structure accommodating groove, so that the steam channels on both sides of the support rib group are interconnected to form an overall steam channel covering different parts of the curved bottom plate; by using a steam groove with a width of 0.5-3mm and a depth the same as the height of the support rib set on the support rib, it can be ensured that the gaseous heat equalizing medium formed after the liquid phase heat equalizing medium in the second capillary structure is vaporized quickly passes through the steam groove into the steam channel outside the support rib, which is conducive to the rapid flow of the gaseous heat equalizing medium.

[0022] In a specific possible implementation scheme, the curved cover plate is fixed to the curved bottom plate by welding to form a sealed connection with the curved bottom plate around the heat-spreading structure accommodating groove.

[0023] By adopting the above-mentioned technical scheme, the curved cover plate is fixed to the curved bottom plate around the heat-equalizing structure accommodating groove by welding, which can form a reliable connection and reliable seal between the curved cover plate and the curved bottom plate, which is conducive to forming the required vacuum degree in the heat-equalizing structure cavity and ensuring the heat transfer performance between the curved cover plate and the curved bottom plate.

[0024] The manufacturing process of the thin curved vapor chamber provided in this application adopts the following technical solution:

[0025] A manufacturing process of a thin curved heat spreader, comprising the following steps: S10, processing a curved bottom plate: forming the curved bottom plate by CNC processing or stamping; S20, installing a second capillary structure: cutting a second capillary structure of a set size and installing it between adjacent support ribs in the support rib group; S30, installing a first capillary structure: cutting a first capillary structure of a set size and installing it above the support rib group in the heat spreader structure receiving groove; S40, welding a curved cover plate: cutting a curved cover plate of a set size and welding it on the curved bottom plate so that the curved cover plate completely covers the heat spreader structure receiving groove to form a heat spreader structure cavity isolated from the outside, and reserving a filling channel between the heat spreader structure cavity and the external space; S50, filling a heat spreader medium: filling a set amount of a heat spreader medium into the heat spreader structure cavity through the filling channel, and then evacuating the heat spreader structure cavity through the filling channel, and then closing the filling channel to obtain the thin curved heat spreader of the present application.

[0026] By adopting the above technical solution and forming the curved bottom plate by CNC processing or stamping, the support ribs and the curved bottom plate can be formed in one piece, thereby ensuring the structural stability of the support ribs and the heat transfer performance between the support ribs and the curved bottom plate; filling the heat equalizing medium in the heat equalizing structure cavity and then evacuating it is beneficial to the gasification of the heat equalizing medium at the bottom temperature, and improving the fluidity of the gas-phase heat equalizing medium vapor, thereby improving the heat equalizing effect of the thin curved heat equalizing plate.

[0027] In a specific possible implementation scheme, the manufacturing process of the thin curved heat sink of the present application further includes the following steps: S60, surface oxidation treatment: performing surface oxidation treatment on the outer surfaces of the curved bottom plate and the curved cover plate.

[0028] By adopting the above-mentioned technical scheme, by utilizing the surface oxidation treatment of the outer surfaces of the curved bottom plate and the curved cover plate, an oxide layer can be formed on the outer surfaces of the curved cover plate and the curved bottom plate. On the one hand, this reduces the conductivity of the heat spreader, and on the other hand, it can prevent the curved cover plate and the curved bottom plate from oxidative corrosion during use, resulting in leakage of the heat spreader medium in the heat spreader structure cavity, thereby increasing the service life of the heat spreader.

[0029] In summary, the present application includes at least one of the following beneficial technical effects:

[0030] 1. The structure of the curved bottom and the curved cover is combined, so that the heat spreader can be formed into a curved shape consistent with the curved structure of the external heating device, and fixed on the curved surface of the heating device by bonding or screwing, and closely fits the heating curved surface, thereby improving the heat spread and heat dissipation effect of the heating device;

[0031] 2. A supporting rib group arranged below the first capillary structure is used to form a larger steam channel below the first capillary structure. While the first capillary structure provides a liquid medium flow channel, it also provides a flow space for the gas phase heat-equalizing medium, thereby ensuring the smooth flow of the heat-equalizing medium, which is beneficial to improving the heat-equalizing effect of the heat-equalizing plate, and can support the first capillary structure and the curved cover plate, thereby ensuring the structural stability of the heat-equalizing plate;

[0032] 3. By utilizing the second capillary structure arranged between the supporting ribs in the supporting rib group, a supplementary flow channel for the liquid-phase equalizing medium can be formed in one dimension, and a channel for the gas-phase equalizing medium to pass through is formed by the steam grooves arranged on the supporting ribs, thereby further promoting the reflux of the liquid-phase equalizing medium and the flow of the gas-phase equalizing medium, effectively improving the heat flux density of the thin curved heat spreader, and ensuring the heat equalization and heat dissipation effects in narrow spaces in special fields such as aerospace. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of an embodiment of a thin curved vapor chamber of the present application.

[0034] Figure 2 This is an exploded view of the parts of an embodiment of the thin curved heat sink of the present application.

[0035] Figure 3 This is a cross-sectional schematic diagram of an embodiment of a thin curved vapor chamber of the present application.

[0036] Figure 4 The flowchart is a flowchart of an embodiment of the manufacturing process of the thin curved heat sink of the present application.

[0037] Explanation of the reference numerals: 1. curved bottom plate; 11. heat-dissipating structure accommodating groove; 12. supporting rib group; 121. steam channel; 13. supporting ribs; 131. steam groove; 2. curved cover plate; 3. first capillary structure; 4. second capillary structure. DETAILED DESCRIPTION

[0038] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0039] In this application, unless otherwise stated, the directions or positional relationships indicated by the directional words such as "upper" and "lower" used are based on the directions or positional relationships of the thin curved vapor chamber of this application in the accompanying drawings, and such directions or positional relationships do not represent the actual directions or positional relationships of the physical structure of the thin curved vapor chamber of this application. The description of the directions or positional relationships of the components in the thin curved vapor chamber of this application is consistent with this.

[0040] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0041] In this specification, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features.

[0042] An embodiment of the thin curved surface heat sink of the present application is as follows: Figures 1 to 3 As shown, it includes a curved bottom plate 1, a curved cover plate 2, a first capillary structure 3 and a second capillary structure 4. The curved bottom plate 1 is made of copper, aluminum or alloy materials thereof, and has good thermal conductivity, which can accelerate the transfer of heat through the curved bottom plate 1 and the transfer between different positions on the curved bottom plate 1, and play an auxiliary heat-balancing role by relying on its own thermal conductivity. The curved bottom plate 1 is set to a spatial curved surface shape consistent with the surface of the external heating device that needs to dissipate heat.

[0043] A heat-equalizing structure accommodating groove 11 is formed on the upper side surface of the curved bottom plate 1. The heat-equalizing structure accommodating groove 11 occupies most of the upper side surface of the curved bottom plate 1. The heat-equalizing structure accommodating groove 11 is recessed downward from the upper side surface of the curved bottom plate 1, and only a strip frame for connecting with the curved cover plate 2 is retained at the edge of the curved bottom plate 1. The bottom of the heat-equalizing structure accommodating groove 11 is parallel to the lower surface of the curved bottom plate 1, that is, the depths of different parts of the heat-equalizing structure accommodating groove 11 are the same. A plurality of support rib groups 12 are provided in the heat-equalizing structure accommodating groove 11. The support rib groups 12 are usually made of the same metal material as the curved bottom plate. The support rib groups 12 can be independently manufactured and fixed on the bottom of the heat-equalizing structure accommodating groove 11, or can be a structure formed when the heat-equalizing structure accommodating groove 11 is processed and connected to the curved bottom plate as a whole. The support rib groups 12 are dispersed on the bottom wall of the heat-equalizing structure accommodating groove 11 , and steam channels 121 are formed between the support rib groups 12 and the side walls of the heat-equalizing structure accommodating groove 11 , and between adjacent support rib groups 12 .

[0044] The support rib group 12 includes at least two support ribs 13 arranged in parallel with each other, and an inter-rib groove flush with the bottom of the heat-equalizing structure accommodating groove 11 is formed between adjacent support ribs 13, and the inter-rib groove is usually arranged in a long strip with a rectangular cross section. The support ribs 13 are provided with steam grooves 131 penetrating both sides of the support ribs 13, so that the steam grooves 131 are connected between the inter-rib grooves and the steam channel 121.

[0045] The first capillary structure 3 is made of porous structural material, usually a thin sheet material with an area equivalent to that of the heat-equalizing structure receiving groove 11, such as porous fiber textiles, porous polymer materials, multi-layer woven wire mesh, porous graphene materials, etc. The first capillary structure 3 is arranged in the heat-equalizing structure receiving groove 11 and is located above the support rib group 12. The capillary pores inside the first capillary structure 3 can be connected to different parts of the heat-equalizing structure receiving groove 11. A plurality of support rib groups 12 form support for the first capillary structure 3 below the first capillary structure 3 to ensure that the steam channel 121 below the first capillary structure 3 is unobstructed.

[0046] The second capillary structure 4 is made of a porous structural material with a thickness equal to the height of the inter-rib groove, and the second capillary structure 4 is arranged in the inter-rib groove between adjacent support ribs 13 inside the support rib group 12. Usually, the thickness of the second capillary structure 4 is much greater than that of the first capillary structure 3, so the second capillary structure 4 with a smaller width also has more capillary pores, forming a large number of capillary channels extending along the inter-rib groove direction.

[0047] The curved cover plate 2 is made of a thin-walled metal sheet, usually made of copper, aluminum or alloy materials thereof with good thermal conductivity. The curved cover plate 2 is processed to form the same spatial curved surface shape as the curved bottom plate 1. The periphery of the curved cover plate 2 is fixed on the curved bottom plate 1 on the outside of the groove wall of the heat-equalizing structure accommodating groove 11, forming a sealed connection with the curved bottom plate 1, so that the curved cover plate 2 covers the groove opening of the heat-equalizing structure accommodating groove 11, forming a heat-equalizing structure cavity isolated from the outside. The heat-equalizing structure cavity is filled with an easily evaporable heat-equalizing medium, and the liquid phase heat-equalizing medium is adsorbed by the capillary channels inside the first capillary structure 3 and the second capillary structure 4, and rapidly diffuses along the first capillary structure 3 and the second capillary structure 4 under the capillary action, covering the entire thin curved heat-equalizing plate area.

[0048] When in use, the curved bottom plate 1 is bonded by adhesive or fixed by screws on the heat dissipation curved surface of the external heating device, so that the lower surface of the curved bottom plate 1 fits tightly with the heat dissipation curved surface. The heat generated by the heating device is transferred to the heat-saturating structure cavity through the curved bottom plate 1, so that the liquid-phase heat-saturating medium in the adjacent area absorbs heat and vaporizes to form a gas-phase heat-saturating medium. The gas-phase heat-saturating medium quickly diffuses in the entire heat-saturating structure cavity along the steam groove 131 and the steam channel 121, and releases heat and condenses in the area with lower temperature, transferring heat to the area with lower temperature of the heat-saturating plate, which is beneficial to the heat dissipation in the heating device. The condensed liquid-phase heat-saturating medium quickly diffuses along the first capillary structure 3 and the second capillary structure 4, and flows back to the heating device area to ensure the circulation of the heat-saturating medium. The directionally arranged second capillary structure 4 can transfer liquid-phase heat-equalizing medium in large quantities and quickly in a certain area, thereby compensating for the insufficient transfer capacity caused by the need for the first capillary structure 3 to transfer liquid-phase heat-equalizing medium in all directions, and further improving the heat flux density of the thin curved heat spreader of the present application.

[0049] In some embodiments of the thin curved vapor chamber of the present application, Figure 1 and Figure 2 As shown, the curved bottom plate 1 can be set to a single cylindrical, conical or quadratic curved surface, or it can be set to a composite spatial curved surface formed by combining cylindrical, conical or quadratic curved surfaces. In the heat-equalizing structure receiving groove 11, the support rib group 12 is set along the generatrix direction of the curved surface, so that the support rib group 12 can extend in a straight line direction, reduce the stress generated by the forming process of the curved bottom plate 1, and ensure the forming accuracy and structural stability of the curved bottom plate 1. When the curved bottom plate 1 is a single curved surface shape, the support rib group 12 extends from one end of the heat-equalizing structure receiving groove 11 to the other end in a straight line direction, and when the curved bottom plate 1 is composed of different curved surfaces, the support rib group 12 extends in a straight line direction within the range of a single curved surface, and can form a certain angle bend on different curved surfaces.

[0050] In some embodiments of the thin curved vapor chamber of the present application, Figures 1 to 3 As shown, there are multiple support rib groups 12, and two support ribs 13 are arranged in each support rib group 12. The width of each support rib 13 is set to 1-5mm. The support ribs 13 with smaller width can prevent the curved bottom plate 1 or the curved cover plate 2 from breaking during curved surface welding. The spacing between two support ribs 13 in the support rib group 12, that is, the width of the inter-rib groove is 3-10mm. The setting of the inter-rib groove can limit the second capillary structure 4 between the two support ribs 13, ensuring that the second capillary structure 4 with high porosity is damaged during the welding process.

[0051] In some embodiments of the thin curved vapor chamber of the present application, Figure 2 and Figure 3As shown, the first capillary structure 3 is a metal woven mesh, preferably a metal woven mesh woven from multiple strands of copper, aluminum, or stainless steel filaments. Generally, the sum of the thickness of the first capillary structure 3 and the height of the supporting ribs 13 is equal to the depth of the heat-saturating structure receiving groove 11. In this way, the upper surface of the first capillary structure 3 above the supporting ribs 13 is flush with the upper surface of the curved bottom plate 1 around the heat-saturating structure receiving groove 11, which is conducive to ensuring the flatness of the curved cover plate 2 and the overall thickness of the thin curved heat-saturating plate of the present application, so that the thin curved heat-saturating plate of the present application is formed with a total thickness of 0.4-10mm.

[0052] In a preferred embodiment of the thin curved vapor chamber of the present application, the mesh number of the metal woven mesh as the first capillary structure 3 is not less than 200 meshes. The metal woven mesh with a high mesh number can form smaller pores inside, which can form a greater adsorption force for the liquid phase vapor chamber, thereby increasing the diffusion speed of the liquid phase vapor chamber inside the first capillary structure 3.

[0053] In some embodiments of the thin curved heat spreader of the present application, the second capillary structure 4 uses a porous metal material or a metal braided wire. Among them, the porous metal material can be foam copper, porous aluminum or porous nickel, or a combination or mixture of two to three materials of foam copper, porous aluminum and porous nickel. The metal braided wire can be woven using multiple strands of fine aluminum wire or multiple strands of fine copper wire. The second capillary structure 4 using metal material can better provide a capillary channel for the diffusion of liquid-phase heat spreader. At the same time, because the metal material itself has good thermal conductivity, the second capillary structure 4 also has a heat transfer effect, further improving the heat flux density of the heat spreader.

[0054] As a specific implementation of the thin curved surface heat sink of the present application, Figure 2 and Figure 3 As shown, the length of the support rib group 12 is smaller than the length of the heat equalizing structure containing groove 11 in the same direction, so that a certain size of gap is formed between the end portions of the support rib group 12 and the side walls of the heat equalizing structure containing groove 11, and the steam channels 121 on both sides of the support rib group 12 are connected through the gap, so that the steam channels 121 are formed into a mesh channel covering the entire heat equalizing structure containing groove 11, so that the liquid-phase heat equalizing medium can flow rapidly within the entire heat equalizing structure containing groove 11, further reducing the flow resistance of the gas-phase heat equalizing medium.

[0055] Among them, the length of the second capillary structure 4 is equal to or slightly smaller than the length of the supporting rib group 12, ensuring that the second capillary structure 4 is located in the inter-rib groove, preventing the end of the second capillary structure 4 from extending out of the supporting rib group 12, occupying the gap between the supporting rib group 12 and the side wall of the heat equalizing structure containing groove 11, and hindering the flow of the gas-phase heat equalizing medium.

[0056] A plurality of steam grooves 131 are arranged at different positions on the support ribs 13. The plurality of steam grooves 131 are divided into several groups and arranged on the support ribs 13. The spacing between the steam grooves 131 in each group is small, and the spacing between the steam grooves 131 in different groups is large. The width of the steam groove 131 is set to 0.5-3mm, and the steam groove 131 completely cuts off the support ribs 13, so that the depth of the steam groove 131 is the same as the height of the support ribs 13. The plurality of steam grooves 131 that completely cut off the support ribs 13 can effectively increase the connection channel area between the inter-rib grooves and the steam channel 121 when the heat spreader is thin and the height of the support ribs 13 is small, ensuring that the gas-phase heat spreader can quickly flow into the steam channel 121 through the steam grooves 131, thereby increasing the phase change cycle speed of the heat spreader under high heat flux density conditions. At the same time, the steam groove 131 can make the support rib 13 no longer continuous, reduce the thermal deformation of the support rib 13 during welding, and provide space for the curved bottom plate 1 and the curved cover plate 2 to deform due to heat, thereby avoiding damage to the curved bottom plate 1 and / or the curved cover plate 2 due to inconsistent deformation of the support rib 13 and the curved bottom plate 1 and the curved cover plate 2.

[0057] In some embodiments of the thin curved heat spreader of the present application, the curved cover plate 2 is welded and fixed to the curved base plate 1 by a welding process, such as diffusion welding, brazing, etc., so that a good sealing connection is formed between the curved cover plate 2 and the curved base plate 1 around the heat spreader structure accommodating groove 11, preventing the heat spreader medium from leaking through the gap between the curved cover plate 2 and the curved base plate 1, thereby ensuring the heat transfer effect of the thin curved heat spreader of the present application.

[0058] An embodiment of the manufacturing process of the thin curved surface heat sink of the present application is as follows: Figure 4 As shown, the following steps are included:

[0059] S10, processing the curved bottom plate.

[0060] CNC processing, i.e. computer digital controlled precision machining, is used to mill the upper surface of the metal sheet at one time to form a set spatial curved surface shape, and at the same time, structures such as the heat-sparing structure accommodating groove 11, supporting ribs 13 and steam grooves 131 are formed by milling, thereby forming a curved bottom plate 1 having the heat-sparing structure accommodating groove 11, supporting ribs 13 and steam grooves 131. For those with a larger curvature of the spatial curved surface, the metal sheet can be firstly processed by stamping to form a set spatial curved surface shape, and then CNC processing is used to mill the heat-sparing structure accommodating groove 11, supporting ribs 13 and steam grooves 131 at one time, thereby forming a curved bottom plate 1 having the heat-sparing structure accommodating groove 11, supporting ribs 13 and steam grooves 131.

[0061] Alternatively, the metal sheet is extruded by stamping, so that the metal material flows and deforms under the extrusion force of the stamping equipment to form structures such as the heat-equalizing structure accommodating groove 11, supporting ribs 13 and steam grooves 131, thereby forming a curved bottom plate 1 with the heat-equalizing structure accommodating groove 11, supporting ribs 13 and steam grooves 131.

[0062] A heat-saturating medium filling hole connected to the heat-saturating structure receiving groove 11 is formed on the outer side surface of the curved bottom plate 1, and the curved bottom plate 1 is ultrasonically cleaned and then put into use.

[0063] S20, installing a second capillary structure.

[0064] A porous metal material of a certain thickness is cut according to the required width and length to obtain multiple second capillary structures 4 that are consistent with the size of the grooves between the ribs on the curved bottom plate 1; or a metal braided wire of a certain diameter is cut according to the length of the grooves between the ribs on the curved bottom plate 1 to obtain multiple second capillary structures 4 that are consistent with the length of the grooves between the ribs.

[0065] After ultrasonic cleaning of the plurality of second capillary structures 4 , the second capillary structures 4 are installed in the grooves between the ribs on the curved bottom plate 1 , so that both ends of the second capillary structures 4 are flush with the grooves between the ribs.

[0066] S30, installing a first capillary structure.

[0067] Take a metal woven mesh that meets the requirements and cut it according to the shape and size of the heat-distributing structure accommodating groove 11 on the curved bottom plate 1 to obtain a first capillary structure 3 that is consistent with the shape and size of the heat-distributing structure accommodating groove 11 .

[0068] After ultrasonic cleaning of the first capillary structure 3 , the first capillary structure 3 is placed in the heat-averaging structure accommodating groove 11 and above the supporting rib group 12 , and pressed flat to form a curved surface having the same shape and curvature as the curved bottom plate 1 .

[0069] S40, welding curved cover plate.

[0070] A metal sheet of a set thickness is taken and cut according to the plane shape and size of the curved bottom plate 1 to obtain a curved cover plate 2 having the same plane shape and size as the curved bottom plate 1 .

[0071] After ultrasonically cleaning the curved cover plate 2, cover the curved cover plate 2 on the curved bottom plate 1 and press it flat to deform the curved cover plate 2 to form a spatial curved surface shape consistent with the shape of the curved bottom plate 1. The curved cover plate 2 is welded to the curved bottom plate 1 around the heat equalizing structure accommodating groove 11.

[0072] When welding, if the brazing process is used, the welding surface of the curved bottom plate 1 around the heat-saturating structure accommodating groove 11 needs to be coated with brazing material in advance. Welding is performed along the edge of the heat-saturating structure accommodating groove 11, and the curved cover plate 2 is pressed flat during welding, so that the gap between the curved cover plate 2 and the curved bottom plate 1 is completely closed by welding. In this way, the curved cover plate 2 completely covers the notch of the heat-saturating structure accommodating groove 11, so that the heat-saturating structure accommodating groove 11 forms a heat-saturating structure cavity isolated from the outside world.

[0073] A short metal tube is inserted into the heat-saturating medium filling hole, and the gap between the outer wall of the metal tube and the wall of the heat-saturating medium filling hole is welded and closed, and the metal tube is used as the heat-saturating medium filling pipe.

[0074] S50, filling with hot working fluid.

[0075] A set amount of liquid phase heat-averaging medium is filled into the heat-averaging structure cavity through the heat-averaging medium filling pipe. The filling amount of liquid phase heat-averaging medium is usually 10-40% of the capacity of the heat-averaging structure cavity. After the filling is completed, the heat-averaging structure cavity is evacuated through the heat-averaging medium filling pipe. It is usually necessary to make the air pressure in the heat-averaging structure cavity less than 10KPa.

[0076] The working fluid filling pipe is welded and sealed to obtain the thin curved heat spreader of the present application.

[0077] In one embodiment of the manufacturing process of the thin curved vapor chamber of the present application, Figure 4 As shown, after step S50, charging the equalizing medium, the following steps are also included:

[0078] S60, surface oxidation treatment.

[0079] The thin curved surface heat spreader is subjected to surface oxidation treatment to form a surface oxide layer on the outer surface of the curved bottom plate 1 and the curved cover plate 2, thereby ensuring the structural stability of the outer surface of the curved bottom plate 1 and the curved cover plate 2, preventing the metal material inside from contacting with external oxygen and water vapor to cause rust, and improving the service life of the thin curved surface heat spreader of the present application. The specific surface oxidation treatment process can be carried out according to the existing common treatment process.

[0080] In the description of the present application, the description with reference to the terms "one embodiment", "specific embodiment", "preferred embodiment", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0081] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A thin curved surface heat sink, characterized in that: The invention comprises a curved bottom plate (1), a curved cover plate (2), a first capillary structure (3) and a second capillary structure (4); the curved bottom plate (1) is provided with a heat-equalizing structure accommodating groove (11); a supporting rib group (12) is provided in the heat-equalizing structure accommodating groove (11); the supporting rib group (12) comprises at least two supporting ribs (13); the supporting ribs (13) are provided with steam grooves (131) penetrating both sides of the supporting ribs (13); the first capillary structure (3) is arranged in the heat-equalizing structure accommodating groove (11) and is located above the supporting rib group (12); the second capillary structure (4) is arranged between the supporting ribs (13) inside the supporting rib group (12); the curved cover plate (2) is fixed on the curved bottom plate (1) and covers the notch of the heat-equalizing structure accommodating groove (11), thereby forming a heat-equalizing structure cavity isolated from the outside; the heat-equalizing structure cavity is filled with a heat-equalizing medium.

2. The thin curved vapor chamber according to claim 1, characterized in that: The curved bottom plate (1) is arranged in the shape of a cylinder, a cone, a quadratic surface or a combination thereof, and the supporting rib group (12) is arranged along the generatrix direction of the curved surface.

3. The thin curved vapor chamber according to claim 2, characterized in that: A plurality of the support rib groups (12) are provided, the width of each support rib (13) inside the support rib group (12) is 1-5 mm, the support rib group (12) includes two support ribs (13), and the spacing between the two support ribs (13) is 3-10 mm.

4. The thin curved vapor chamber according to claim 1, characterized in that: The first capillary structure (3) is a metal woven mesh, and the sum of the thickness of the first capillary structure (3) and the height of the supporting ribs (13) is equal to the depth of the heat-dissipating structure accommodating groove (11).

5. The thin curved vapor chamber according to claim 4, characterized in that: The first capillary structure (3) is a metal woven mesh with a mesh number of not less than 200 meshes.

6. The thin curved vapor chamber according to claim 1, characterized in that: The second capillary structure (4) is a porous metal material or a metal braided wire, and the porous metal material is at least one of foam copper, porous aluminum, and porous nickel.

7. The thin curved vapor chamber according to claim 6, characterized in that: The length of the support rib group (12) is less than the length of the heat-equalizing structure containing groove (11) in the same direction, the length of the second capillary structure (4) is not greater than the length of the support rib group (12), the width of the steam groove (131) is 0.5-3 mm, and the depth is the same as the height of the support rib (13).

8. The thin curved vapor chamber according to any one of claims 1 to 7, characterized in that: The curved cover plate (2) is fixed to the curved bottom plate (1) by welding, forming a sealed connection with the curved bottom plate (1) around the heat-equalizing structure accommodating groove (11).

9. A process for manufacturing a thin curved vapor chamber according to any one of claims 1 to 8, characterized in that: The following steps are involved: S10, processing the curved bottom plate: forming the curved bottom plate (1) by CNC processing or stamping; S20, installing the second capillary structure: cutting the second capillary structure (4) to a set size, and installing it between adjacent support ribs (13) in the support rib group (12); S30, installing the first capillary structure: cutting the first capillary structure (3) to a set size, and installing it above the supporting rib group (12) in the heat-dissipating structure receiving groove (11); S40, welding the curved cover plate: cutting the curved cover plate (2) to a set size, and welding it to the curved bottom plate (1), so that the curved cover plate (2) completely covers the heat-saturating structure receiving groove (11), forming a heat-saturating structure cavity isolated from the outside, and reserving a filling channel between the heat-saturating structure cavity and the external space; S50, filling with a heat-saturating medium: filling a set amount of a heat-saturating medium into the heat-saturating structure cavity through the filling channel, and then evacuating the heat-saturating structure cavity through the filling channel, and then closing the filling channel to obtain a thin curved heat-saturating plate.

10. The manufacturing process according to claim 9, characterized in that: The following steps are also included: S60, surface oxidation treatment: performing surface oxidation treatment on the outer surfaces of the curved bottom plate (1) and the curved cover plate (2).

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