A heat dissipation device and a preparation method thereof

Abstract

The embodiment of the application discloses a heat dissipation device and a preparation method thereof, which comprise a sealed shell, a liquid absorbing core and phase change working medium. The sealed shell comprises a first shell and a second shell, and the first shell and the second shell jointly form a cavity. The liquid absorbing core is arranged in the cavity and comprises a porous body formed by mutually stacking and sintering a plurality of copper-plated diamond particles. The copper-plated diamond particle comprises a diamond particle and a metal layer wrapping the diamond particle. The particle size of the diamond particle is 5-25 mu m. The packing density of the porous body is 63.5%-84%, and the porosity is 16%-35%. The phase change working medium is filled in the cavity. The copper-plated diamond particle prepared by using small particle size diamond is tightly stacked to form a porous structure with low porosity and small pore size, strong capillary suction force is generated, and the heat dissipation efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of heat dissipation technology for electronic components, and in particular to a heat dissipation device and its preparation method. Background Technology

[0002] Vapor chambers (VCs), as a highly efficient phase-change heat dissipation technology, are widely used in the thermal management of high-power electronic devices. The basic principle of a vapor chamber is as follows: a liquid wick and a phase-change working fluid are placed within a vacuum-sealed chamber. The working fluid absorbs heat and vaporizes in the evaporation zone. The vapor diffuses to the condensation zone, releasing heat and condensing. The condensed liquid working fluid then flows back to the evaporation zone under the capillary force of the liquid wick, forming an "evaporation-condensation-reflux" phase-change cycle, thereby achieving highly efficient heat dissipation.

[0003] Existing vapor chambers typically employ porous pure copper structures such as sintered copper powder, copper mesh, or copper foam as their wicking cores. Their equivalent thermal conductivity is limited by the inherent thermal conductivity of copper, making it difficult to meet the demands of rapid heat diffusion under high heat flux densities. When the temperature difference between the heat source and the condenser is small, the phase change cycle driving force of traditional vapor chambers weakens, resulting in a significant decrease in heat dissipation performance. Summary of the Invention

[0004] This application provides a heat dissipation device and its preparation method, which uses copper-plated diamond particles prepared with small-diameter diamonds to form a porous structure with low porosity and small pore size through close packing, thereby generating strong capillary suction force and improving heat dissipation efficiency.

[0005] This application provides a heat dissipation device, including: A sealed housing includes a first housing and a second housing, wherein the first housing and the second housing together form a cavity; A liquid-absorbing core is disposed within the cavity. The liquid-absorbing core comprises a porous body formed by stacking and sintering multiple copper-plated diamond particles. Each copper-plated diamond particle comprises a diamond particle and a metal layer encapsulating the diamond particle. The diamond particle has a particle size of 5-25 μm. The bulk density of the porous body is 63.5%–84%, and the porosity is 16%–35%. A phase change working fluid is filled into the cavity.

[0006] Optionally, the metal layer includes a copper plating layer with a thickness of 8-12 μm.

[0007] Optionally, the metal layer further includes a transition layer disposed between the diamond particle and the encapsulation layer.

[0008] Optionally, the transition layer is a titanium layer, a chromium layer, or a tungsten layer, or a carbide layer formed by at least one element selected from titanium, chromium, or tungsten, and the thickness of the transition layer is 0.1-1 μm.

[0009] Optionally, a plurality of support tubes are provided between the first housing and the second housing, and the support tubes connect to the cavity between the first housing and the second housing.

[0010] Optionally, a flowing core wire is provided inside the support tube, and the flowing core wire is a metal wire bundle, fiber bundle, or porous material strip.

[0011] Optionally, the sealing housing is a copper or copper alloy housing.

[0012] Optionally, the outer surface of the first housing is used for thermal contact with an external heat source, and the outer surface of the second housing is provided with heat dissipation fins.

[0013] This application also provides a method for manufacturing a heat dissipation device, including: Diamond particles are provided, and the diamond particles are subjected to surface metallization treatment to form a metal layer encapsulating the diamond particles, thereby obtaining copper-plated diamond particles. Multiple copper-plated diamond particles are filled into a mold and pressurized to a bulk density of 63.5%–84%. Sintering is performed at a temperature of 700℃~800℃ to connect the multiple copper-plated diamond particles to form a porous body; the porous body is then placed on the inner surface of the sealed shell as a liquid-absorbing core. At least one support tube is welded between the first housing and the second housing, so that the support tube connects the cavity between the first housing and the second housing; The first housing and the second housing are sealed together to form a vacuum cavity; The vacuum cavity is filled with a phase change working fluid and then sealed.

[0014] Optionally, the step of surface metallization treatment of the diamond particles specifically includes: First, a transition layer is formed on the surface of the diamond particle. The transition layer is a titanium layer, a chromium layer, or a tungsten layer, or a carbide layer formed by at least one element selected from titanium, chromium, or tungsten. Then, the copper plating layer is formed on the surface of the transition layer.

[0015] The beneficial effects of this application are: This application embodiment uses small-diameter diamond particles to prepare copper-plated diamond particles. The diamond particles are completely coated with a metal layer and sintered to form a continuous three-dimensional high thermal conductivity framework. The ultra-high thermal conductivity of diamond allows heat to diffuse rapidly laterally. At the same time, by controlling its packing density, a porous structure with small pores is formed, thereby generating a stronger capillary suction force. This ensures that the liquid working fluid can overcome gravity and flow resistance and stably flow back to the evaporation zone. Even when the heat source power fluctuates or the device is placed at an angle, it is not easy to dry out. This achieves the synergistic effect of the high thermal conductivity framework and strong capillary force, ensuring the continuous and stable operation of the phase change cycle and improving the heat dissipation efficiency of the heat dissipation device under small temperature difference conditions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is an exploded view of the heat dissipation device in the embodiments of this application.

[0018] Figure 2 This is a cross-sectional view of one embodiment of the heat dissipation device in this application.

[0019] Figure 3 This is a cross-sectional view of another embodiment of the heat dissipation device in this application.

[0020] Explanation of reference numerals in the attached figures: 1-First shell; 2-Second shell; 3-Liquid suction core; 4-Support tube; 5-Cavity. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be described in detail below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] It should be noted that: throughout the accompanying drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions; in the description of this application, the terms "center," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; in the description of this application, "first," "second," etc., are only used to distinguish each other, and do not indicate their degree of importance or order, etc.

[0023] In the description of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to fixed connections, movable connections, or detachable connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication between two components, etc. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] To facilitate understanding, the markings in the attached diagram are explained first: Mark 1 is the first shell, which together with the second shell forms a sealed shell; Mark 2 is the second shell, which is positioned opposite to the first shell; Mark 3 is the liquid-absorbing core, which is a porous body formed by the stacking and sintering of multiple copper-plated diamond particles; Mark 4 is the support tube, which is positioned between the first shell and the second shell; Mark 5 is the cavity, which is formed by the enclosing of the first shell and the second shell.

[0025] refer to Figure 1 This application implements a heat dissipation device, including: The sealed housing includes a first housing 1 and a second housing 2, wherein the first housing 1 and the second housing 2 together form a cavity 5; A liquid-absorbing core 3 is disposed within the cavity 5. The liquid-absorbing core 3 comprises a porous body formed by stacking and sintering multiple copper-plated diamond particles. The copper-plated diamond particles include diamond particles and a metal layer encapsulating the diamond particles. The particle size of the diamond particles is 5-25 μm. The packing density of the porous body is 63.5% to 84%, and the porosity is 16% to 35%. A phase change working fluid is filled into the cavity 5.

[0026] Specifically, the first shell 1 and the second shell 2 are arranged opposite to each other, and are sealed together by diffusion welding, brazing, or laser welding to form a closed vacuum cavity. The liquid-absorbing core 3 is disposed within the cavity 5 and is fixedly attached to the inner surfaces of the first shell 1 and the second shell 2. The liquid-absorbing core 3 is composed of a sponge-like porous body formed by the stacking and sintering of multiple copper-plated diamond particles, with uniformly distributed micropores inside. Each copper-plated diamond particle has a core-shell structure, including a diamond particle at the center and a metal layer surrounding the outer surface of the diamond particle. The particle size of the diamond particles is 5μm to 25μm. The multiple copper-plated diamond particles are connected by sintering the metal layers to form sintered necks, thereby forming a porous body with structural strength. The packing density of the porous body is 63.5% to 84%, corresponding to a porosity of 16% to 35%. These pores are interconnected to form capillary channels. The phase change working fluid fills the cavity 5 and wets the pores in the porous body of the liquid-absorbing core 3. The phase change working fluid is high-purity water or electronic fluorinated liquid. The low porosity design of the porous body results in small internal pore diameters, thereby generating strong capillary suction force to ensure that the liquid working fluid can overcome gravity and flow resistance and stably flow back to the evaporation zone.

[0027] In some possible implementations, the metal layer includes a copper plating layer with a thickness of 8-12 μm. The copper plating layer completely coats the outer surface of the diamond particles in a uniform and dense manner, forming a core-shell structure with diamond as the core and copper plating layer as the outer shell. This thickness range allows for the formation of sufficiently large sintering necks between the copper layers on the surfaces of adjacent copper-plated diamond particles in a stacked state. This means that the copper plating layers of adjacent particles diffuse and fuse together during high-temperature sintering, connecting the discrete particles into a continuous three-dimensional porous body. Simultaneously, this thickness range ensures complete coating of the diamond particles without excessively thickening to the point of clogging pores due to copper layer accumulation. Therefore, controlling the copper plating thickness within 8-12 μm guarantees complete encapsulation of the diamond particles, forming good thermal conductivity pathways, without excessively increasing particle size and affecting packing density and porosity. In this embodiment, the copper plating thickness is preferably 10 μm.

[0028] In some possible implementations, the metal layer further includes a transition layer disposed between the diamond particle and the copper plating. Specifically, the transition layer completely covers the outer surface of the diamond particle in the form of a thin film, and the copper plating completely covers the outer surface of the transition layer, thereby forming a three-layer core-shell structure of diamond particle-transition layer-copper plating. The transition layer is used to strengthen the interfacial bonding strength between the diamond particle and the copper plating, avoid interfacial delamination due to differences in thermal expansion coefficients, and improve the service life and thermal cycling stability of the heat dissipation device.

[0029] In some possible implementations, the transition layer is a titanium layer, a chromium layer, or a tungsten layer, or a carbide layer formed from at least one of titanium, chromium, or tungsten, and the thickness of the transition layer is 0.1-1 μm.

[0030] Specifically, the transition layer can be formed on the surface of the diamond particles using physical vapor deposition (PVD), chemical vapor deposition (CVD), or magnetron sputtering. It completely coats the outer surface of the diamond particles in a continuous, dense film form, while the copper plating completely coats the outer surface of the transition layer, thus forming a three-layer core-shell structure: diamond particle-transition layer-copper plating. The transition layer is made of titanium, chromium, or tungsten, or a carbide layer formed by at least one of these metals (such as titanium carbide TiC, chromium carbide Cr3C2 or Cr7C3, tungsten carbide WC, etc.). These metals are all strong carbide-forming elements. During subsequent sintering, the metal elements or their carbides in the transition layer undergo interfacial reactions or lattice matching with the carbon atoms on the surface of the diamond particles, generating a continuous, dense carbide interfacial layer. The carbide interface layer forms a strong chemical bond with the diamond surface, while the outer side of the carbide layer has good metal wettability and atomic diffusion ability with the copper plating layer, thus forming a low thermal resistance and high strength metallurgical bonding interface between the diamond particles and the copper plating layer. At the same time, the interface formed by chemical bonding has higher bonding strength and thermal fatigue resistance. It can maintain structural stability after multiple thermal cycles and is not prone to interface peeling or particle shedding, thus ensuring the reliability of the wick and the long-term stability of heat dissipation performance during long-term operation.

[0031] The transition layer, with a thickness of 0.1-1 μm, forms a continuous, dense, and pinhole-free complete cover layer on the diamond particle surface. If the transition layer thickness is less than 0.1 μm, uneven deposition can easily lead to localized exposed areas. This prevents the exposed diamond surface from effectively bonding with the copper plating during subsequent sintering, resulting in interface defects and localized high thermal resistance, thus reducing the overall thermal conductivity of the wick. If the transition layer is too thick (exceeding 1 μm), a noticeable drop in thermal resistance occurs as heat passes through it, weakening the diamond's ultra-high thermal conductivity.

[0032] In some possible implementations, a plurality of support tubes 4 are provided between the first housing 1 and the second housing 2, and the support tubes 4 connect to the cavity between the first housing 1 and the second housing 2. The support tubes 4 are hollow tubes, with both ends fixedly connected to the inner surfaces of the first housing 1 and the second housing 2, respectively. The tube walls of the support tubes 4 form an internal channel that connects to the cavity between the first housing 1 and the second housing 2; that is, both ends of the support tubes 4 communicate with the cavity, allowing vapor or liquid working fluid within the cavity to flow freely through the interior of the support tubes 4. The plurality of support tubes 4 are evenly distributed between the first housing 1 and the second housing 2, forming an array-type support structure. The support tube 4 serves as a structural support, resisting the pressure difference generated by atmospheric pressure after vacuuming the cavity, preventing the first shell 1 and the second shell 2 from concave inward or sticking together, thereby maintaining the thickness and shape stability of the cavity. Furthermore, the internal channel of the support tube 4 provides an additional flow path for the phase change working fluid, offering a directional channel for the condensed liquid working fluid to flow back from the second shell 2 side to the first shell 1 side, complementing the capillary reflux of the wick 3. The support tube 4 is made of the same material as the sealing shell to ensure a consistent coefficient of thermal expansion and prevent connection failure due to thermal stress.

[0033] In some possible implementations, a flow core wire is provided inside the support tube 4. The flow core wire is a metal wire bundle, fiber bundle, or porous material strip to enhance the liquid reflux capability and improve the overall heat transfer performance of the heat dissipation device.

[0034] Specifically, the flowing core wire extends axially along the support tube 4, its outer diameter matching the inner diameter of the support tube 4, and it tightly fills the internal channel of the support tube 4 or maintains contact with the inner wall of the support tube 4. The flowing core wire is a metal wire bundle, fiber bundle, or porous material strip. The thermal conductivity of the flowing core wire is lower than that of the sealed shell. The metal wire bundle is formed by twisting or parallel bundling of multiple fine metal wires (such as copper wire or stainless steel wire), with axially extending micro-gap between the metal wires; the fiber bundle is formed by bundling multiple polymer fibers (such as nylon or polyester) or glass fibers, with the gaps between the fibers forming capillary channels; the porous material strip is a flexible or rigid porous body with an open structure (such as foamed metal, sintered fiber felt, or porous ceramic strip), with three-dimensionally interconnected micropores inside. The two ends of the flowing core wire extend to the openings at both ends of the support tube 4, and form contact or capillary connection with the liquid-absorbing core 3 on the first shell 1 side and the inner wall or condensate collection area on the second shell 2 side. When the condensed liquid working fluid gathers on the second shell 2 side, the flowing core wire, through the capillary force generated by the micro-slits or pores inside, continuously draws the liquid working fluid from the second shell 2 end of the support tube 4 to the first shell 1 end, and directly releases it into the evaporation zone of the absorbing core 3. A small gap can be left between the flowing core wire and the inner wall of the support tube 4, or it can be tightly attached to the inner wall; when using a metal wire bundle, the bundle density can be adjusted according to the required capillary force. The flowing core wire transforms the support tube, while providing structural support, into an active liquid return channel. Working in parallel with the porous body of the absorbing core, it jointly transports the condensed liquid from the condensation end back to the evaporation end, thereby enhancing the return flow capacity of the entire heat dissipation device, preventing dry-out failure due to insufficient local return flow, and improving the overall heat transfer performance.

[0035] In some possible embodiments, the sealing housing is made of copper or a copper alloy. Copper or copper alloys have high thermal conductivity, resulting in excellent heat transfer between the inner and outer surfaces of the housing. This allows for efficient transfer of heat from external heat sources to the internal wicking core and rapid dissipation of heat from the condensation side to the external environment or heat dissipation fins. Simultaneously, copper and copper alloys possess good weldability and machinability, facilitating the sealing welding (e.g., diffusion welding, brazing, or laser welding) between the first housing 1 and the second housing 2, and also facilitating the fixed connection (e.g., brazing) between the internal components such as the wicking core 3 and the support tube 4 and the inner surface of the housing. Furthermore, copper or copper alloys exhibit excellent material compatibility with the copper plating in the copper-plated diamond particles and with copper components such as the support tube 4 and the flow core wire, preventing electrochemical corrosion caused by dissimilar metal contact and ensuring the structural stability and reliability of the heat dissipation device during long-term use.

[0036] In some possible embodiments, the outer surface of the first housing 1 is used for thermal contact with an external heat source, and the outer surface of the second housing 2 is provided with heat dissipation fins. Specifically, the outer surface of the first housing 1 is a flat bonding surface for direct contact with an external heat source (such as the packaging surface of an AI chip, GPU, or CPU), and a thermally conductive interface material can be coated between them to reduce contact thermal resistance. The outer surface of the second housing 2 is integrally formed or fixed with multiple heat dissipation fins by welding. The heat dissipation fins are thin sheet-like metal plates arranged parallel to each other and extending outward along the outer surface of the second housing 2. The extending direction of the heat dissipation fins is perpendicular or inclined to the surface of the second housing 2, and airflow channels are formed between adjacent fins. After the first housing 1 is in contact with the external heat source, heat is transferred through the first housing 1 to the wick and working fluid, and finally to the second housing 2; the heat dissipation fins on the outer surface of the second housing 2 rapidly dissipate heat into the environment by increasing the contact area with the surrounding air. The contact between the outer surface of the first housing 1 and the heat source, and the connection between the outer surface of the second housing 2 and the heat dissipation fins, together form the main heat dissipation path from the heat source to the environment, so that the heat released at the condensation end in the phase change cycle can be efficiently discharged, maintaining the temperature difference between the condensation end and the evaporation end, thereby ensuring the continuous driving of the phase change cycle.

[0037] In some possible implementations, the heat dissipation device can be selected in different shapes and layouts according to actual application requirements.

[0038] refer to Figure 2 When the heat dissipation device is applied to a flat, sealed housing, the first housing 1 and the second housing 2 are located on opposite sides of the thickness direction of the wicking core 3, i.e., the two housings are vertically opposite each other, forming a vertical heat dissipation structure. The area of ​​the housing in contact with the external heat source is the evaporation zone, and the area of ​​the housing with heat dissipation fins is the condensation zone. This configuration is suitable for uniform temperature dissipation of large-area chips, effectively eliminating hot spots and improving the temperature uniformity of the chip. During operation, heat from the heat source is transferred through the evaporation zone housing to the evaporation zone of the wicking core. The working fluid absorbs heat and vaporizes. The vapor diffuses to the condensation zone housing inside the condensation zone housing, where it releases heat and condenses. The condensed liquid working fluid flows back to the evaporation zone under the capillary force of the wicking core, completing the phase change cycle.

[0039] refer to Figure 3When the heat dissipation device is applied to a slender, sealed housing, the first housing 1 and the second housing 2 are located at opposite ends of the length direction of the absorbing core 3, i.e., the two housings are positioned left and right opposite each other, forming a horizontal heat dissipation structure. The area of ​​the housing in contact with the external heat source is the evaporation zone, and the area of ​​the housing with heat dissipation fins is the condensation zone. This configuration is suitable for long-distance heat extraction from high-power-density hotspots, enabling efficient long-distance heat transfer. During operation, heat from the heat source is transferred through the evaporation zone housing to the left-end evaporation zone of the absorbing core. The working fluid absorbs heat and vaporizes. The vapor diffuses along the length direction of the absorbing core to the right-end condensation zone, where it releases heat and condenses. The condensed liquid working fluid then flows back to the left-end evaporation zone under the capillary force of the absorbing core, completing the phase change cycle.

[0040] It should be noted that, in the two forms described above, the specific orientations of the first housing 1 and the second housing 2 are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art should understand that, regardless of whether a flat or elongated form is used, the outer surface of the first housing 1 is always in thermal contact with an external heat source, and the outer surface of the second housing 2 is provided with heat dissipation fins to maintain the functional allocation between the evaporation end and the condensation end.

[0041] In some possible implementations, this application also provides a method for manufacturing a heat dissipation device, the method comprising the following steps: Step S1: Provide diamond particles and perform surface metallization treatment on the diamond particles to obtain copper-plated diamond particles. Specifically, a transition layer with a thickness of 0.1μm to 1μm is deposited on the surface of the diamond particles using physical vapor deposition or magnetron sputtering, so that the transition layer continuously and densely coats the diamond particles; then, the diamond particles coated with the transition layer are transferred into a chemical plating tank or an electroplating tank, and a copper plating layer with a thickness of 8μm to 12μm is deposited on their surface to obtain copper-plated diamond particles with a three-layer core-shell structure.

[0042] Step S2: Fill a plurality of the copper-plated diamond particles into a mold and pressurize them to a bulk density of 63.5% to 84%. Specifically, the copper-plated diamond particles are loaded into a metal mold with a predetermined cavity shape, and pressure is applied by a hydraulic press to make the particles tightly packed together, so that the void volume percentage between the particles is 16% to 35%.

[0043] Step S3: Sintering is performed at a temperature of 700℃~800℃ to interconnect the multiple copper-plated diamond particles and form a porous body. Specifically, the mold filled with particles and pressurized is placed in a protective atmosphere sintering furnace, and nitrogen or argon protective gas is introduced, or the furnace is evacuated to a vacuum state, and heated to 700℃~800℃. During the sintering process, the copper plating on the surface of adjacent copper-plated diamond particles melts and diffuses, forming sintering necks, which solidify the discrete particles into a porous body with three-dimensional interconnected pores. After sintering, the porous body is cooled to room temperature with the furnace and then demolded.

[0044] Step S4: The porous body is placed on the inner surface of the sealed housing as a liquid-absorbing core. Specifically, this includes: cutting the porous body to a size that matches the inner surface of the first housing 1; uniformly coating the inner surface of the first housing 1 with a layer of brazing filler; placing the porous body on the brazing filler; and then heating it in a vacuum brazing furnace to the brazing temperature, so that the porous body and the inner surface of the first housing 1 are firmly connected through the brazing filler layer.

[0045] Step S5: Weld at least one support tube 4 between the first housing 1 and the second housing 2, so that the support tube 4 connects the cavity between the first housing 1 and the second housing 2. Specifically, this includes: pre-processing welding holes or welding bosses at corresponding positions of the first housing 1 and the second housing 2, inserting both ends of the support tube 4 into the holes respectively, and pre-inserting a flowable core wire into the support tube 4, and sealing and fixing both ends of the support tube 4 to the housing by laser welding or brazing.

[0046] Step S6: Seal the first housing 1 and the second housing 2 to form a vacuum cavity.

[0047] Step S7: Fill the vacuum cavity with a phase change working fluid and seal it. Specifically, through a pre-drilled injection port, inject high-purity water or electronic fluorinated liquid into the vacuum cavity, allowing the liquid to wet the porous body of the absorber core. After the liquid is filled, perform cold pressure welding or laser sealing welding on the injection port to complete the seal.

[0048] The heat dissipation device of the present invention can be applied to electronic devices with high heat flux density. Specifically, it includes, but is not limited to, the following applications: First type of application: Heat dissipation of high-performance computing chips This invention can be applied to heat dissipation of high-power AI chips (such as GPUs, TPUs, ASICs, NPUs, etc.), high-performance computing processors (CPUs), FPGAs, and other computing chips. Taking AI training chips as an example, their operating heat flux density can reach over 100W / cm², which traditional air-cooling and liquid-cooling solutions cannot meet. By attaching the outer surface of the first housing 1 of the heat dissipation device of this invention to the packaging surface of the AI ​​chip, and setting heat dissipation fins on the outer surface of the second housing 2 in conjunction with a fan, heat transfer can be achieved even when the temperature difference between the chip and the heat dissipation environment is small, thereby controlling the chip temperature and ensuring stable chip operation and computing power output.

[0049] Second application: Heat dissipation of power electronic devices This invention can be applied to heat dissipation of high heat flux density power electronic devices such as high-power LEDs (e.g., streetlights, car headlights, projector light sources), IGBT modules (e.g., new energy vehicle motor controllers, photovoltaic inverters, high-speed rail traction systems), 5G base station RF power amplifiers (AAU), and lasers. Taking new energy vehicle IGBT modules as an example, they generate a large amount of heat during operation, and the installation space is limited, making it difficult to effectively arrange traditional heat sinks. The heat dissipation device of this invention is designed as a thin plate, embedded between the IGBT module and the cooling plate. Utilizing its efficient heat transfer capability under small temperature differences, the heat generated by the IGBT chip is quickly conducted to the cooling plate and carried away by the vehicle's cooling system, thereby reducing the IGBT junction temperature and improving the module's reliability and lifespan.

[0050] Furthermore, this invention can also be applied to heat dissipation in consumer electronics products, such as high-performance smartphones, tablets, game consoles, and VR / AR devices. Taking foldable screen phones as an example, their internal space is extremely limited, and the folding area has strict requirements on thickness. The heat dissipation device of this invention can be customized into an irregularly shaped thin sheet according to the internal space of the foldable screen phone, and attached to the surface of the motherboard and battery, so as to evenly conduct heat to the phone's mid-frame and screen back panel, avoid local hot spots, and improve the user experience.

[0051] Note that the above are merely preferred embodiments and the technical principles employed in this application. Those skilled in the art will understand that this application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of this application, the scope of which is determined by the scope of the appended claims.

Claims

1. A heat dissipation device, characterized in that, include: A sealed housing includes a first housing and a second housing, wherein the first housing and the second housing together form a cavity; A liquid-absorbing core is disposed within the cavity. The liquid-absorbing core comprises a porous body formed by stacking and sintering multiple copper-plated diamond particles. Each copper-plated diamond particle comprises a diamond particle and a metal layer encapsulating the diamond particle. The diamond particle has a particle size of 5-25 μm. The bulk density of the porous body is 63.5%–84%, and the porosity is 16%–35%. A phase change working fluid is filled into the cavity.

2. The heat dissipation device according to claim 1, characterized in that, The metal layer includes a copper plating layer with a thickness of 8-12 μm.

3. The heat dissipation device according to claim 2, characterized in that, The metal layer further includes a transition layer disposed between the diamond particle and the encapsulation layer.

4. The heat dissipation device according to claim 3, characterized in that, The transition layer is a titanium layer, a chromium layer, or a tungsten layer, or a carbide layer formed by at least one element selected from titanium, chromium, or tungsten, and the thickness of the transition layer is 0.1-1 μm.

5. The heat dissipation device according to claim 1, characterized in that, A plurality of support tubes are provided between the first housing and the second housing, and the support tubes connect the cavity between the first housing and the second housing.

6. The heat dissipation device according to claim 5, characterized in that, The support tube contains a flowing core wire, which is a metal wire bundle, fiber bundle, or porous material strip.

7. The heat dissipation device according to claim 1, characterized in that, The sealing housing is made of copper or a copper alloy.

8. The heat dissipation device according to claim 1, characterized in that, The outer surface of the first housing is used for thermal contact with an external heat source, and the outer surface of the second housing is provided with heat dissipation fins.

9. A method for preparing a heat dissipation device, characterized in that, The heat dissipation device according to any one of claims 1 to 8 includes the following steps: Diamond particles are provided, and the diamond particles are subjected to surface metallization treatment to form a metal layer encapsulating the diamond particles, thereby obtaining copper-plated diamond particles. Multiple copper-plated diamond particles are filled into a mold and pressurized to a bulk density of 63.5%–84%. Sintering is performed at a temperature of 700℃~800℃ to connect the multiple copper-plated diamond particles to form a porous body; the porous body is then placed on the inner surface of the sealed shell as a liquid-absorbing core. At least one support tube is welded between the first housing and the second housing, so that the support tube connects the cavity between the first housing and the second housing; The first housing and the second housing are sealed together to form a vacuum cavity; The vacuum cavity is filled with a phase change working fluid and then sealed.

10. The preparation method according to claim 9, characterized in that, The specific steps of surface metallization treatment of the diamond particles include: First, a transition layer is formed on the surface of the diamond particle. The transition layer is a titanium layer, a chromium layer, or a tungsten layer, or a carbide layer formed by at least one element selected from titanium, chromium, or tungsten. Then, the copper plating layer is formed on the surface of the transition layer.

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