Vapor chamber and preparation method thereof

Abstract

The invention discloses a vapor chamber and a preparation method thereof, the vapor chamber comprises an upper cover plate, a lower cover plate and a capillary structure, the upper cover plate and the lower cover plate form a sealed cavity, and the capillary structure is packaged in the sealed cavity; the capillary structure comprises a liquid backflow layer, a steam transmission layer and a supporting layer which are overlapped, and the liquid backflow layer is used for guiding liquid condensed by the condensation area back to the evaporation area again through the capillary action; the steam transmission layer is used for providing a low-resistance path for steam to move to the condensation area; and the supporting layer is used for providing support for the liquid backflow layer and the steam transmission layer. The heat dissipation reliability of the vapor chamber can be improved.

Description

Technical Field

[0001] This application belongs to the technical field of heat dissipation, and particularly relates to a vapor chamber and a preparation method thereof. Background Art

[0002] With the development of artificial intelligence technology, the power consumption of high-performance computing components such as CPUs and GPUs has been continuously increasing. Consumer electronic products are facing the challenge of improving heat dissipation efficiency while maintaining a thin and light design. Traditional fans are difficult to further downsize due to their complex structure, and heat pipes cannot meet customized requirements because of their fixed shape. Moreover, the existing capillary structure designs of vapor chambers (such as planar meshes or printed metal powders) have encountered bottlenecks when reaching a thickness of T0.25 mm and can no longer adapt to more stringent size limitations and the demand for efficient heat dissipation. Therefore, there is an urgent need for an optimized capillary structure design solution that not only realizes further miniaturization and ultrathinness of products but also ensures efficient heat transfer and liquid circulation, and can flexibly adapt to various internal space layouts to address the heat dissipation challenges of consumer electronic products. Summary of the Invention

[0003] The main purpose of this application is to provide a vapor chamber and a preparation method thereof, which can improve the heat dissipation reliability of the vapor chamber.

[0004] To achieve the above objectives, this application provides the following technical solutions:

[0005] A vapor chamber, comprising: an upper cover plate, a lower cover plate, and a capillary structure. Among them, the upper cover plate and the lower cover plate form a sealed cavity, and the capillary structure is encapsulated between the sealed cavities; the capillary structure includes a superimposed liquid reflux layer, a vapor transmission layer, and a support layer. Among them, the liquid reflux layer is used to re-guide the liquid condensed in the condensation area back to the evaporation area through capillary action; the vapor transmission layer is used to provide a low-resistance path for the vapor to move to the condensation area; the support layer is used to provide support for the liquid reflux layer and the vapor transmission layer.

[0006] Optionally, a microchannel network is provided in the liquid reflux layer.

[0007] Optionally, the microchannel network adopts a vein structure.

[0008] Optionally, a plurality of vapor channels are provided on the vapor transmission layer.

[0009] Optionally, the plurality of vapor channels are radially arranged in the vapor transmission layer.

[0010] Optionally, support components are provided on one side of the upper cover plate and the lower cover plate relative to the capillary structure.

[0011] Optionally, the support component includes a plurality of support ribs, the plurality of support ribs are arranged corresponding to the plurality of steam channels, each support rib includes a plurality of support columns arranged at intervals, and each support column corresponds to a reserved hole arranged in the steam channel one by one.

[0012] Optionally, a first water injection port is arranged on one side of the upper cover plate, a second water injection port is arranged on one side of the lower cover plate, and the first water injection port corresponds to the second water injection port and forms a water injection structure.

[0013] Optionally, the surface of the capillary structure is coated with a coating.

[0014] The present application also provides a method for manufacturing a heat pipe, and the manufacturing method includes: respectively processing and manufacturing an upper cover plate, a lower cover plate and support columns by stamping or etching; manufacturing a capillary structure containing steam channels by blanking or laser cutting; assembling and welding the upper cover plate, the lower cover plate and the capillary structure to obtain a heat pipe.

[0015] The present application can bring the following beneficial effects: The present application can optimize the liquid reflux path and improve the steam transmission efficiency, ensure efficient heat transfer and uniform temperature distribution, and at the same time enhance the anti-pollution ability and long-term operation stability of the system, so as to significantly improve the heat dissipation performance and reliability of the heat pipe, and meet the requirements of high-performance electronic devices for efficient heat dissipation solutions. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of a heat pipe provided by an embodiment of the present application;

[0017] Figure 2 is a schematic structural diagram of the upper cover plate provided by another embodiment of the present application;

[0018] Figure 3 is a schematic structural diagram of the lower cover plate provided by another embodiment of the present application;

[0019] Figure 4 is a schematic structural diagram of the capillary structure provided by another embodiment of the present application;

[0020] Figure 5 is a schematic structural diagram of the microchannel network in the liquid reflux layer provided by another embodiment of the present application;

[0021] Figure 6 is a schematic flow chart of a method for manufacturing a heat pipe provided by another embodiment of the present application.

[0022] Description of the reference numerals is as follows:

[0023] 1. Upper cover plate; 2. Lower cover plate; 3. Capillary structure; 3-1. Liquid reflux layer; 3-2. Vapor transmission layer; 3-3. Support layer; 3-4. Vapor channel; 3-4-1. Main channel; 3-4-2. Secondary channel; 3-4-3. Capillary channel; 4. Liquid injection tube; 5-1. Support rib; 5-2. Support column; 6. First water injection port; 7. Second water injection port; Detailed implementation manners

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] It should be noted that all directional indications (such as up, down, left, right, front, back,...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0026] In the present invention, unless otherwise clearly defined and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0027] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, such descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and / or" appearing throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution where A and B are satisfied simultaneously. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0028] In an exemplary embodiment, as Figure 1As shown, the present application provides a heat pipe, which includes an upper cover plate 1, a lower cover plate 2, and a capillary structure 3. Among them, a sealed cavity is formed between the upper cover plate 1 and the lower cover plate 2, and the capillary structure 3 is encapsulated between the sealed cavities; the capillary structure 3 includes a stacked liquid return layer 3-1, a vapor transmission layer 3-2, and a support layer 3-3. Among them, the liquid return layer 3-1 is used to redirect the liquid condensed in the condensation area back to the evaporation area through capillary action; the vapor transmission layer 3-2 is used to provide a low-resistance path for the vapor to move to the condensation area; the support layer 3-3 is used to provide support for the liquid return layer 3-1 and the vapor transmission layer 3-2.

[0029] In this embodiment, the liquid return layer 3-1 is used to redirect the liquid condensed in the condensation area back to the evaporation area through capillary action. This design can ensure the smoothness and directionality of liquid flow, avoid the accumulation of liquid in the condensation area, and improve the liquid circulation efficiency. The vapor transmission layer 3-2 can provide a low-resistance path for the vapor to move to the condensation area, which helps the vapor to quickly diffuse to the condensation area and can complete heat transfer in a short time. The support layer 3-3 can provide necessary physical support for the liquid return layer 3-1 and the vapor transmission layer 3-2, preventing the upper cover plate 1 and the lower cover plate 2 from sticking to each other or deforming due to the internal and external pressure difference during the vacuum pumping process. Through the combined action of the liquid return layer 3-1, the vapor transmission layer 3-2, and the support layer 3-3, efficient heat transfer and uniform temperature distribution can be achieved, and the optimization of the liquid return path and the improvement of the vapor transmission efficiency can be realized. Coupled with the enhanced structural stability, these all directly contribute to the improvement of the overall heat dissipation performance.

[0030] In addition, the materials most suitable for their functional requirements should be selected for each layer in the capillary structure 3. For example, for the liquid return layer 3-1, materials with high porosity and strong hydrophilicity, such as copper mesh or copper foam, need to be used; for the vapor transmission layer 3-2, a sintered metal powder body or other lightweight materials with low surface roughness and good fluidity should be selected; while the support layer 3-3 needs to have sufficient strength and thermal conductivity, such as high-strength alloys or graphene-reinforced materials can be used.

[0031] In another exemplary embodiment, a microchannel network is provided in the liquid return layer 3-1.

[0032] In this embodiment, the microchannel network can effectively capture and guide the liquid flow, while reducing the liquid film thickness and avoiding liquid accumulation. In addition, in the present application, the microchannel network is designed in a vein structure, including a main channel 3-4-1, secondary channels 3-4-2, and capillary channels 3-4-3. Among them, the main channel 3-4-1 serves as the main path connecting the evaporation area and the condensation area, and can quickly and effectively guide the condensed liquid from the condensation area back to the evaporation area, thereby ensuring the directionality and continuity of the liquid flow and improving the liquid reflux efficiency. The secondary channels 3-4-2 are distributed on both sides of the main channel, and the capillary channels 3-4-3 are located on both sides of the secondary channels. Through the hierarchical arrangement of the secondary channels 3-4-2 and the capillary channels 3-4-3, the liquid flow path can be refined, making the liquid film distribution more uniform, reducing the possibility of local liquid accumulation. The thin and uniform liquid film helps to reduce the liquid reflux resistance, thereby promoting the rapid exchange between the vapor and the liquid.

[0033] In summary, the hierarchical design of the main channel 3-4-1, secondary channels 3-4-2, and capillary channels 3-4-3 provides multiple low-resistance paths for the vapor, helps the vapor to quickly diffuse to the condensation area, and can complete the heat transfer in a short time, thereby enhancing the overall heat dissipation performance.

[0034] In another exemplary embodiment, a plurality of vapor channels 3-4 are provided on the vapor transmission layer 3-2.

[0035] In this embodiment, by providing a plurality of vapor channels 3-4 on the vapor transmission layer 3-2, firstly, the volume of the vapor cavity (the vapor cavity refers to the open space specifically designed for vapor flow inside the heat pipe. In this cavity, the vapor can freely move from the evaporation area to the condensation area to be cooled and condensed into a liquid, and then return to the evaporation area through capillary action or other mechanisms to complete the gas-liquid two-phase flow cycle) can be significantly increased, providing more flow space for the vapor, which helps to improve the vapor transmission efficiency from the evaporation area to the condensation area, thereby enhancing the overall heat dissipation performance; secondly, the vapor flow path can be optimized. The design of the vapor channels 3-4 can guide the vapor to flow along a predetermined path, reducing unnecessary detours or obstacles, and reducing the resistance during the vapor transmission process. This not only ensures that the vapor can flow more smoothly from the evaporation area to the condensation area, but also improves the overall efficiency of the gas-liquid two-phase flow, making the heat transfer more rapid and effective; thirdly, it can assist the liquid reflux. When the vapor is guided to the condensation area, the formed low-pressure area helps to attract the liquid to return to the evaporation area through the capillary structure 3, maintaining an efficient liquid cycle, thereby avoiding liquid accumulation in certain areas, ensuring the uniformity of the liquid distribution throughout the system, and further improving the heat dissipation efficiency.

[0036] In another exemplary embodiment, the plurality of steam channels 3-4 are radially arranged within the steam transmission layer 3-2.

[0037] In this embodiment, the radial arrangement of the steam channels 3-4 mimics the way of sunlight radiation, with the heat source position of the heat sink equal to the radiation source. This design enables heat to be evenly diffused from the center to the surroundings, thereby maximizing the use of the entire surface of the heat sink for heat dissipation. Through the radial arrangement, the steam channels 3-4 can more directly transport the steam generated in the evaporation area to the condensation area, thus reducing the distance and time of heat transfer and improving the heat transfer efficiency. Further, the radial arrangement helps to evenly distribute the steam flow rate, avoiding steam concentration in a certain area, thereby preventing local overheating, and ensuring uniform heat distribution across the entire heat sink, enhancing the overall heat dissipation effect.

[0038] It should be noted that the steam channels 3-4 can be adjusted according to the specific shape of the heat sink and the heat dissipation direction to optimize the steam flow path. Exemplarily,

[0039] Adjustment according to the shape of the heat sink

[0040] Example 1: Rectangular heat sink

[0041] Shape characteristics: A rectangular heat sink has a regular length-to-width ratio and is commonly used in standard-sized electronic devices.

[0042] Adjustment method: In a rectangular heat sink, the steam channels 3-4 can be designed to be radially distributed from the center to the four corners, or parallel steam channels 3-4 can be arranged along the long side and the short side. Such a layout can ensure uniform steam diffusion across the entire surface and improve the heat dissipation efficiency.

[0043] Specific arrangement: If the heat source is located at the center, a radial arrangement can be adopted; if the heat source is concentrated on one side, more steam channels 3-4 can be added on that side to quickly conduct heat.

[0044] Example 2: Circular or oval heat sink

[0045] Shape characteristics: Circular or oval heat sinks are suitable for electronic devices with special shapes, such as certain portable devices or modules with specific shapes.

[0046] Adjustment method: For circular or oval heat sinks, the steam channels 3-4 can be radially distributed from the center outwards, or annular steam channels 3-4 can be arranged along the circumferential direction. The annular channels help to maintain temperature equilibrium in the edge area and prevent local overheating.

[0047] Specific layout: If the heat source is located at the center, a radial layout is adopted; if the heat sources are distributed at the edge, an annular channel can be added at the edge to enhance the heat dissipation effect in the edge area.

[0048] 2. Adjust according to the heat dissipation direction

[0049] Example 3: Unidirectional heat dissipation (such as mobile phones)

[0050] Heat dissipation direction: Devices such as mobile phones usually need to transfer heat from the CPU / GPU area to positions far from the heat source, such as the screen or the back.

[0051] Adjustment method: In this case, the vapor channel 3-4 can extend from the heat source position in a single direction to form a straight or slightly curved channel, transferring heat to the condensation area along the shortest path.

[0052] Specific layout: The vapor channel 3-4 can be designed to lead directly from the CPU / GPU area to areas with better heat dissipation, such as the edge of the housing or the location of the heat sink, ensuring rapid heat dissipation.

[0053] Example 4: Multi-directional heat dissipation (such as laptops)

[0054] Heat dissipation direction: The internal space of laptops is complex, and heat may need to be transferred in multiple directions, such as both sides, the top, or the bottom.

[0055] Adjustment method: For multi-directional heat dissipation requirements, the vapor channel 3-4 can extend from the heat source position in multiple directions to form a mesh or branched structure. This can ensure that heat is evenly dispersed to each heat dissipation area.

[0056] Specific layout: For example, in a laptop, multiple branched vapor channels 3-4 can be set around the CPU area and lead to different heat dissipation modules, such as fans, heat sinks, or different parts of the housing, to achieve all-round heat dissipation.

[0057] 3. Comprehensive adjustment combining shape and heat dissipation direction

[0058] Example 5: Anisotropic vapor chamber (such as irregularly shaped embedded devices)

[0059] Shape characteristics: Anisotropic vapor chambers are suitable for embedded devices with complex shapes, which have irregular shapes and diverse heat dissipation requirements.

[0060] Adjustment method: For anisotropic vapor chambers, the design of the vapor channel 3-4 needs to be customized according to the shape and heat dissipation direction. The heat transfer path can be simulated through simulation software to find the optimal layout of the vapor channel 3-4.

[0061] Specific arrangement: For example, in an L-shaped vapor chamber, if the heat source is located at a corner, a steam channel 3-4 extending outward from the corner can be designed to ensure that heat is quickly transferred to other parts and that structural stability is maintained through appropriate support columns.

[0062] Summary of adjustment principles:

[0063] Maximize heat dissipation area: Regardless of the shape of the vapor chamber, the vapor channels 3-4 should cover the entire surface as much as possible to maximize the heat dissipation area.

[0064] Optimize the heat transfer path: Steam channels 3-4 should shorten the heat transfer distance as much as possible to reduce heat loss and ensure efficient heat transfer.

[0065] Avoid liquid accumulation: The width of steam channel 3-4 needs to be controlled within 20mm or less to avoid liquid accumulation and ensure smooth liquid reflux.

[0066] Adaptable design: According to the needs of specific application scenarios, the layout of steam channels 3-4 can be flexibly adjusted to ensure system stability and reliability.

[0067] In another exemplary embodiment, the width of the steam channel 3 - 4 is 10 mm to 20 mm.

[0068] In this embodiment, the width of the steam channel 3-4 is designed to be between 10 mm and 20 mm mainly based on the following considerations:

[0069] 1. In the heat spreader, liquid reflux mainly depends on capillary action. If the steam channel 3-4 is too wide (greater than 20mm), the liquid cannot be effectively attracted back to the evaporation zone through capillary action, resulting in liquid accumulation and affecting the heat dissipation efficiency. On the contrary, if the steam channel is too narrow (less than 10mm), the cross-sectional area of ​​the steam channel 3-4 will be significantly reduced, which will increase the flow resistance of the steam in the channel. The higher flow resistance will lead to a decrease in the steam transmission efficiency, thereby affecting the heat transfer rate from the evaporation zone to the condensation zone, thereby reducing the overall heat dissipation performance. Therefore, setting the width to 10mm to 20mm helps maintain sufficient capillary force to ensure that the liquid can reflux smoothly.

[0070] 2. The channel width of this size helps to form a more uniform steam flow field, allowing steam to quickly exchange between the evaporation area and the condensation area, thereby improving the heat transfer efficiency of the entire system. At the same time, this is also conducive to reducing the occurrence of local overheating and ensuring uniform distribution of heat on the entire heat plate.

[0071] 3. To prevent the upper cover plate 1 and the lower cover plate 2 from adhering to each other or deforming due to the internal and external pressure difference during the vacuum pumping process, support columns 5-2 are provided inside the steam channel 3-4 in this application. These support columns 5-2 not only provide mechanical support but also serve to separate the steam channel 3-4. If the channel is too wide, more or larger support columns are required to maintain the structural stability, but this may impede the steam flow and occupy too much space. If the channel is too narrow, the size of the support columns 5-2 will be correspondingly reduced, and the mechanical support provided by the smaller support columns 5-2 is limited and insufficient to prevent the upper cover plate 1 and the lower cover plate 2 from adhering or deforming due to the internal and external pressure difference during the vacuum pumping process. In addition, overly thin support columns 5-2 are prone to breakage or failure during manufacturing or use, thus affecting the long-term reliability of the heat pipe. Therefore, controlling the channel width within the range of 10 mm to 20 mm can ensure the support effect without significantly affecting the steam flow.

[0072] In another exemplary embodiment, support assemblies are provided on one side of the upper cover plate 1 and the lower cover plate 2 relative to the capillary structure 3.

[0073] In this embodiment, the support assembly includes a plurality of support ribs 5-1, the plurality of support ribs 5-1 are arranged corresponding to the plurality of steam channels 3-4, and each support rib 5-1 includes a plurality of support columns 5-2 arranged at intervals. In addition, a plurality of reserved holes are provided in the steam channel 3-4, and the reserved holes correspond to the support columns 5-2 one by one.

[0074] By providing the support columns 5-2, a certain amount of mechanical support can be provided to prevent the upper cover plate 1 and the lower cover plate 2 from adhering to each other or deforming due to the internal and external pressure difference during the vacuum pumping process, thereby ensuring the flatness of the heat pipe and avoiding the appearance of dents. In addition, by providing the support columns 5-2, it is also beneficial to maintain the openness of the steam channel 3-4 and the stability of its internal structure to ensure that steam can flow freely and liquid can flow back smoothly. Further, since the support columns 5-2 are usually made of materials with good thermal conductivity (such as copper), the support columns 5-2 can also effectively help heat spread from the hot spot area, thereby reducing the risk of local overheating.

[0075] It should be noted that the height and diameter of the support columns 5-2 need to be matched according to the thickness of the heat pipe and the height of the internal chamber to ensure that neither the steam flow is obstructed nor sufficient support strength is provided. Below, this application illustrates how to select appropriate support column sizes according to the specific parameters of the heat pipe by way of examples.

[0076] Example 1: Standard heat pipe (T 0.25 mm)

[0077] The parameters of the heat pipe include: overall thickness: 0.2 mm, internal cavity height: 0.14 mm, upper and lower cover plate wall thickness: 0.03 mm.

[0078] Then the corresponding support posts are designed as follows: height: 0.14 mm (equal to the internal cavity height of the heat pipe), diameter: 0.1 mm (considering the requirement that the width of the steam channel 3-4 ≤ 20 mm, the diameter of the support posts is smaller to reduce the impact on steam flow).

[0079] It should be noted that the height of the support post 5-2 is set to 0.14 mm, which is exactly equal to the internal cavity height of the steam channel 3-4. This ensures that the support post can fully support the upper cover plate 1 and the lower cover plate 2, preventing the two from sticking together during the vacuum pumping process.

[0080] The diameter of the support post 5-2 is set to 0.1 mm, which not only ensures sufficient support strength but also does not impede steam flow. This small-diameter design makes the gap between the support posts 5-2 large enough to allow steam to flow freely, and liquid can flow back smoothly through the capillary structure 3.

[0081] Example 2: Thinner heat pipe (T < 0.2 mm)

[0082] The parameters of the heat pipe include: overall thickness: 0.18 mm, internal cavity height: 0.1 mm, upper and lower cover plate wall thickness: 0.04 mm.

[0083] Then the corresponding support post 5-2 is designed as follows: height: 0.1 mm (equal to the internal cavity height of the heat pipe),

[0084] diameter: 0.08 mm (further reducing the diameter to adapt to the thinner internal cavity).

[0085] It should be noted that in the above-mentioned thinner heat pipe, the height of the support post 5-2 is also set to be equal to the internal cavity height, that is, 0.1 mm, in order to ensure that the support post 5-2 can effectively support the upper cover plate 1 and the lower cover plate 2 and maintain the stability of the internal structure.

[0086] The diameter of the support post 5-2 is reduced to 0.08 mm to adapt to the thinner internal cavity and ensure that there is enough space for steam to flow in the steam channel 3-4. This design also reduces the resistance that may be encountered during liquid reflux.

[0087] Example 3: Thicker heat pipe (T = 0.5 mm)

[0088] The parameters of the heat pipe include: overall thickness: 0.5 mm, internal cavity height: 0.3 mm, upper and lower cover plate wall thickness: 0.1 mm.

[0089] The corresponding support column 5-2 is designed as follows: height: 0.3 mm (equal to the height of the internal cavity of the heat sink), diameter: 0.2 mm (the diameter is appropriately increased to enhance the support strength).

[0090] It should be noted that for a relatively thick heat sink, the height of the support column 5-2 is set to 0.3 mm, which matches the height of the internal cavity, ensuring sufficient clearance between the upper cover plate 1 and the lower cover plate 2 for steam flow.

[0091] The diameter of the support column 5-2 can be appropriately increased to 0.2 mm because in this case, the space of the internal cavity is larger, and a support column 5-2 with a larger diameter can be accommodated without affecting steam flow. At the same time, the larger diameter provides stronger support force and enhances the structural stability.

[0092] In summary, the height of the support column 5-2 should be equal to the height of the internal cavity of the heat sink to ensure that the support column 5-2 can completely fill the cavity, provide effective mechanical support, and avoid adhesion between the upper cover plate 1 and the lower cover plate 2. In addition, the diameter of the support column 5-2 should be as small as possible to reduce the obstruction to steam flow, but at the same time, sufficient support strength should be ensured. Generally, the diameter of the support column 5-2 should not exceed 1 / 5 to 1 / 10 of the width of the steam channel 3-4 to ensure the openness of the steam channel 3-4 and the smoothness of liquid reflux. Through the above examples, it can be seen that the height and diameter of the support column 5-2 must be precisely matched according to the overall thickness of the heat sink and the height of the internal chamber to ensure the best mechanical support effect and heat dissipation performance.

[0093] In another exemplary embodiment, please refer to Figure 1 , a first water injection port 6 is provided on one side of the upper cover plate 1, and a second water injection port 7 is provided on one side of the lower cover plate 2. The first water injection port 6 and the second water injection port 7 correspond to each other and form a water injection structure.

[0094] In this embodiment, the water injection structure is connected to a liquid injection pipe 4. Before the heat sink is assembled and sealed, it is necessary to ensure that the water injection structure (i.e., the first water injection port 6 and the second water injection port 7) is in an open state and the liquid injection pipe 4 is connected. To ensure that the working liquid can be evenly distributed in the capillary structure 3 and to avoid air remaining inside and affecting performance, before injecting the working liquid, the heat sink is first evacuated to remove the air inside the heat sink, reduce the resistance during steam transmission, and improve the liquid reflux efficiency. When the required vacuum degree is reached inside the heat sink, an appropriate amount of working liquid (usually a low-boiling-point liquid such as water, ethanol, etc.) is injected into the heat sink through the liquid injection pipe 4. Since the inside of the heat sink is in a low-pressure environment at this time, the liquid is easily sucked into the capillary structure 3. Once the correct amount of working liquid is injected, the first water injection port and the second water injection port need to be quickly sealed, which can be achieved by welding or other reliable sealing methods to ensure that the internal vacuum state and the appropriate amount of working liquid are maintained without leakage.

[0095] The main functions of the first water injection port 6 and the second water injection port 7 are to provide an inlet for the sealed cavity inside the heat sink for filling the working medium (usually water or other low-boiling-point liquids). These media will turn into steam when heated in the evaporation zone and move to the condensation zone through the steam transmission layer 3-2, where they are cooled and turn back into liquid, and then are brought back to the evaporation zone by the liquid reflux layer 3-1 through capillary action. This cycle process is the key mechanism for the heat sink to achieve efficient heat dissipation.

[0096] In another exemplary embodiment, the surface of the capillary structure 3 is coated with a coating.

[0097] In this embodiment, the coating is a hydrophilic or hydrophobic coating. Among them, the hydrophilic coating includes, for example, titanium oxide coating, silica coating or polyvinyl alcohol, and the hydrophobic coating includes, for example, fluorinated polymer coating, silicone coating or graphene-based composite coating. The hydrophilic coating can significantly increase the wettability of the liquid on the solid surface, thereby strengthening the capillary action, making the liquid easier to be attracted to the evaporation zone and evenly distributed throughout the capillary structure 3, so as to improve the interaction force between the liquid and the capillary structure 3, and further ensure that the condensed liquid can quickly and smoothly return to the evaporation zone to maintain an efficient liquid cycle. The hydrophobic coating can guide the steam to flow along a specific path, reduce the residence time of the steam in the unexpected area, and reduce the possibility of condensation.

[0098] It should be noted that which type of coating to choose depends on the specific application requirements and the characteristics of the working environment. For example, in a high-humidity environment, it is more inclined to use a hydrophobic coating to prevent moisture intrusion; while in a dry environment, a hydrophilic coating can be selected to strengthen liquid management.

[0099] In summary, by applying an appropriate coating on the surface of the capillary structure 3, not only can the liquid reflux characteristics be improved, but also the vapor transmission path can be further optimized, thereby providing a customized solution for heat pipes in different application scenarios.

[0100] Figure 6 FIG. is a schematic flow chart of a method for manufacturing a heat pipe according to an embodiment of the present application. As Figure 6 shown, the manufacturing method includes the following steps:

[0101] S1: Use a high-precision stamping die or a laser etching device to process and manufacture the upper cover plate, the lower cover plate, and the support columns by stamping or etching respectively;

[0102] In this step, the present application performs micro-nano structuring on the inner sides of the upper cover plate and the lower cover plate. For example, micro-textures are created through electrochemical etching or nanoimprinting technology to enhance the capillary force and promote liquid reflux.

[0103] S2: Use a precision blanking tool or a laser cutting machine to manufacture a capillary structure with a vapor channel by blanking or laser cutting;

[0104] In this step, the capillary structure 3 can be composed of multiple layers of different materials. For example, a hydrophilic material (such as copper mesh or copper foam and silica, etc.) is combined with a hydrophobic material (such as nano-scale silica or graphene-based composite coating, etc.) to achieve more efficient liquid management and vapor transmission. Specifically, the hydrophilic material has a high porosity and good wettability, and can effectively attract the condensed liquid through capillary action, ensuring that it quickly returns to the evaporation area, helping to maintain an efficient liquid cycle, avoiding liquid accumulation in the condensation area, and thus reducing the thermal resistance. The hydrophobic material can form a barrier in specific areas to prevent the liquid from overly penetrating to unwanted places. For example, using a hydrophobic coating near the vapor channel 3-4 can guide the liquid to flow along a predetermined path instead of dispersing over the entire surface, thereby improving the precision of liquid management.

[0105] In addition, the present application creatively embeds a functional material, such as a phase change material (PCM), in the capillary structure 3, so that the capillary structure 3 can absorb excess heat under high-temperature conditions and play a role of temporary energy storage.

[0106] S3: Assemble and weld the upper cover plate, the lower cover plate, and the capillary structure to obtain a heat pipe.

[0107] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.

Claims

1. A heat sink, characterized in that: The heat sink comprises: An upper cover plate (1), a lower cover plate (2) and a capillary structure (3), wherein: The upper cover plate (1) and the lower cover plate (2) form a sealed cavity, and the capillary structure (3) is encapsulated between the sealed cavity; The capillary structure (3) comprises a stacked liquid reflux layer (3-1), a vapor transmission layer (3-2) and a support layer (3-3), wherein: The liquid reflux layer (3-1) is used to guide the liquid condensed in the condensation zone back to the evaporation zone through capillary action; The vapor transmission layer (3-2) is used to provide a low resistance path for the vapor to move to the condensation zone; The support layer (3-3) is used to provide support for the liquid reflux layer (3-1) and the vapor transmission layer (3-2).

2. The vapor chamber according to claim 1, characterized in that: A microchannel network is provided in the liquid reflux layer (3-1).

3. The heat sink according to claim 2, characterized in that: The microchannel network adopts a leaf vein structure.

4. The vapor chamber according to claim 1, characterized in that: A plurality of steam channels (3-4) are arranged on the steam transmission layer (3-2).

5. The vapor chamber according to claim 4, characterized in that: The plurality of steam channels (3-4) are radially arranged in the steam transmission layer (3-2).

6. The vapor chamber according to claim 1, characterized in that: A support component is provided on one side of the upper cover plate (1) and the lower cover plate (2) relative to the capillary structure (3).

7. The vapor chamber according to claim 6, characterized in that: The support assembly comprises: A plurality of support ribs (5-1), the plurality of support ribs (5-1) being arranged corresponding to the plurality of steam channels (3-4), each support rib (5-1) comprising a plurality of support columns (5-2) arranged at intervals, each support column (5-2) corresponding one-to-one to a reserved hole arranged in the steam channel (3-4).

8. The vapor chamber according to claim 1, characterized in that: A first water injection port (6) is provided on one side of the upper cover plate (1), and a second water injection port (7) is provided on one side of the lower cover plate (2); the first water injection port (6) corresponds to the second water injection port (7) and forms a water injection structure.

9. The vapor chamber according to claim 1, characterized in that: The surface of the capillary structure (3) is coated with a coating.

10. A method for preparing a vapor chamber, characterized in that: The preparation method comprises: The upper cover plate, the lower cover plate and the support column are respectively manufactured by stamping or etching; The capillary structure containing the steam channel is produced by punching or laser cutting; The upper cover plate, the lower cover plate and the capillary structure are assembled and welded to obtain a heat spreader.

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