Liquid cooling heat dissipation device and preparation method thereof

Abstract

The application discloses a liquid cooling heat dissipation device and a preparation method thereof. The device is arranged in an inverted S shape through the whole water flow channel design, compared with a traditional straight flow channel, the heat dissipation device increases the contact area of the refrigerant and the heat dissipation surface, significantly improves the heat exchange efficiency, and meets the heat dissipation demand of high power density; the preparation method adopts an integrated packaging scheme for the heat dissipation device, the whole weight is light, the structure is compact, easy to integrate and install, and the leakage risk of traditional welding or mechanical sealing is eliminated by adopting nano injection integrated packaging, the air tightness test qualified rate is high, and the preparation method has strong manufacturing process compatibility: the process flow of extrusion molding + cutting + nano surface treatment + twice injection is compatible with existing batch manufacturing equipment, and is suitable for large-scale mass production; the leakage risk of traditional welding or mechanical sealing is eliminated by nano injection integrated packaging, and the air tightness test qualified rate is high.

Description

Technical Field

[0001] This invention relates to the field of liquid cooling heat dissipation devices, and in particular to a liquid cooling heat dissipation device and its preparation method. Background Technology

[0002] With the rapid development of new energy vehicles and energy storage systems, the requirements for heat dissipation capacity, structural compactness, and lightweight design of thermal management systems are increasing. Liquid cooling heat sinks are currently the mainstream high-efficiency heat dissipation solution, the core of which lies in the circulation of liquid refrigerant in internal channels to remove a large amount of heat. Existing liquid cooling heat sink technology has the following main problems: (1) Traditional liquid cooling plates are usually made of all-aluminum alloy or copper-aluminum composite structure and are manufactured by welding, brazing or friction stir welding, which are complex processes, require large equipment investment and have high manufacturing costs. (2) Traditional DC channel design results in a short contact path between the refrigerant and the heat dissipation surface, which limits the heat exchange efficiency and makes it difficult to meet the heat dissipation requirements of high power density. (3) The connection between the metal liquid cooling plate and the external structural components requires the use of sealing components or additional fastening structures, which has problems such as poor sealing reliability, a large number of components, and complex assembly. (4) The all-metal liquid cooling plate has poor insulation performance. In high-voltage application scenarios such as battery packs, an additional insulation layer is required, which increases the system complexity and weight. (5) The bonding between metal and plastic relies on traditional adhesives or mechanical bonding, which has limited bonding strength and insufficient long-term reliability. Summary of the Invention

[0003] In view of this, the present invention addresses the deficiencies of the prior art, and its main objective is to provide a liquid cooling heat dissipation device and its preparation method, which solves the problem of limited heat exchange efficiency.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a liquid cooling heat dissipation device, comprising a heat dissipation plate having a water inlet end and a water outlet end, wherein the water inlet end is provided with a water inlet component communicating with the water inlet end, and a water inlet space and a second water passage space are formed between the water inlet component and the water inlet end; the water outlet end is provided with a water outlet component communicating with the water outlet end, and a first water passage space and a water outlet space are formed between the water outlet component and the water outlet end. The heat sink has multiple water passages, including a first water passage, a second water passage, and a third water passage, which connect the water inlet and the water outlet. The water flows sequentially through the water inlet space, the first water passage, the first water passage space, the second water passage, the second water passage space, the third water passage, and the water outlet space.

[0005] In one embodiment of this application, the first water passage is centrally located inside the heat sink, the second water passage is located outside the first water passage, and the third water passage is located outside the second water passage; one end of the first water passage is connected to the water inlet space, and the other end is connected to the middle position of the first water passage space; one end of the second water passage is connected to the outside of the first water passage space, and the other end is connected to the inside of the second water passage space; one end of the third water passage is connected to the outside of the second water passage space, and the other end is connected to the water outlet space.

[0006] In one embodiment of this application, there are four first water passages, four second water passages, and two second water passages are located on both sides of the first water passage; there are eight third water passages, and the eight third water passages are evenly distributed on both sides of the second water passage.

[0007] In one embodiment of this application, the water inlet assembly includes a first connector and a first mounting member disposed outside the first connector. The first connector includes a first main body, two first blocking portions extending inwardly from the inner wall of the first main body and spaced apart, and first capping portions extending inwardly from both ends of the first main body. The two first blocking portions are respectively connected to the walls of corresponding first water passages. The two first capping portions respectively cover the two sides of the water inlet end. The water inlet space is formed between the inner wall of the first main body and the two first blocking portions. The second water passage space is formed between the inner wall of the first main body and one of the first blocking portions and one of the first capping portions. The first mounting member is provided with a water inlet and a water inlet pipe, one end of the water inlet pipe being connected to the water inlet and the other end being connected to the water inlet space.

[0008] In one embodiment of this application, the water outlet assembly includes a second connector and a second mounting member disposed on the outside of the second connector. The second connector includes a first main body, two second blocking portions extending inwardly from the inner wall of the first main body and spaced apart, and second cap portions extending inwardly from both ends of the second main body. The two second blocking portions are respectively connected to the walls of corresponding second water passages, and the distance between the two second blocking portions is greater than the distance between the two first blocking portions. The two second cap portions respectively cover both sides of the water outlet end. The first water passage space is formed between the inner wall of the second main body and the two second blocking parts; the water outlet space is formed between the inner wall of the second main body and the corresponding second blocking part and the corresponding second sealing part; the second mounting member is provided with a water outlet and a water outlet pipe, one end of the water outlet pipe is connected to the water outlet and the other end is connected to the water outlet space.

[0009] In one embodiment of this application, both the first blocking part and the second blocking part are provided with a groove, and the wall of the first water passage or the second water passage is inserted into the groove and bonded.

[0010] In one embodiment of this application, the first mounting component is connected to the water inlet end; the second mounting component is integrally formed and connected to the water outlet end.

[0011] A method for preparing a liquid cooling heat dissipation device includes the following steps: (1) Extrusion molding of heat dissipation plate: Aluminum alloy profiles with a multi-hole flat tube cross section are prepared by extrusion molding machine. The wall thickness, hole shape and outer dimensions are controlled to ensure that the cross section of each water passage is uniform. (2) Heat sink plate cutting: According to the design dimensions of the heat sink plate, the extruded aluminum alloy profile is precisely cut to form the first water passage, the second water passage and the third water passage inside, and the end face is flat, burrs are removed, and dimensional accuracy is guaranteed. (3) Surface treatment: Chemical etching or nano-etching is performed on the surface of the cut heat sink to form a uniform and dense nano-scale microporous structure on the surface of the heat sink. After treatment, the surface is cleaned and dried, and the surface cleanliness is strictly controlled to prevent secondary pollution. (4) One-time injection molding: The first connector and the water inlet pipe, as well as the second connector and the water outlet pipe, are pre-placed in the one-time injection mold. The mold is closed and the glue is injected to make the first connector and the water inlet pipe connected to the first injection assembly, and the second connector and the water outlet pipe connected to the second injection assembly. (5) Flow channel bonding: Apply high-temperature resistant structural adhesive to the designated positions at the water inlet and water outlet of the heat sink, bond the first injection molding assembly to the water inlet, and form a water inlet space and a second water passage space between the first injection molding assembly and the water inlet; bond the second injection molding assembly to the water outlet, and form a first water passage space and a water outlet space between the second injection molding assembly and the water outlet; after the flow channel is assembled, the water flows sequentially through the water inlet space, the first water passage channel, the first water passage space, the second water passage channel, the second water passage space, the third water passage channel and the water outlet space; after bonding, perform curing and airtightness testing to ensure that there is no leakage in the flow channel; (6): Secondary injection molding: The bonded workpiece is placed into a secondary injection mold for nano-injection molding, the mold is closed and the glue is injected. The first mounting part is injection molded on the surface of the water inlet end, and the second mounting part is injection molded on the surface of the water outlet end. The first and second mounting parts are injection molded together with the microporous structure to obtain a complete liquid cooling heat dissipation device. (7): Finished product inspection: Perform appearance inspection, dimensional inspection, airtightness test, insulation resistance test, bonding strength test, refrigerant corrosion resistance test, etc. on the finished products. Qualified products are put into storage.

[0012] In one embodiment of this application, step (3) surface treatment includes the following steps: (3.1) Degreasing treatment: The cut heat sink is placed into the ultrasonic pre-degreasing device and the ultrasonic main degreasing device in sequence for two ultrasonic degreasing processes. The environmentally friendly degreasing liquid in the ultrasonic pre-degreasing device and the ultrasonic main degreasing device performs ultrasonic degreasing on the heat sink under the action of ultrasound, removing oil and dirt from the surface of the product. (3.2) Cleaning 1: Place the heat sink plate that has been ultrasonically cleaned into the corresponding water washing tank for two-stage overflow cleaning and rinsing; (3.3) Activation: The heat sink plate after cleaning 1 is placed in the activation tank to react with the activation liquid, removing surface oxides and organic matter, and generating micron-level pits on the surface of the heat sink plate; (3.4) Roughening: The activated heat sink is placed in a roughening solution for surface roughening, and primary nanopores are formed on the surface of the heat sink. (3.5) Cleaning 2: Place the heat sink after the roughening reaction is completed into the corresponding water washing tank for three-stage overflow deionized water rinsing; (3.6) Anodizing: The surface of the heat sink after cleaning 2 is anodized to form an oxide film layer and secondary nano-sized pores on the surface of the heat sink; (3.7) Cleaning 3: The heat sink after anodizing is subjected to rough cleaning, spraying, and soaking in pure water in sequence; (3.8) Low temperature drying: The heat sink after cleaning 3 is dried in a hot air environment of 60-70℃ for 5-8 minutes.

[0013] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution: By arranging the entire water flow channel in an inverted S-shape, compared to the traditional direct flow channel, the heat dissipation device of this application increases the contact area between the refrigerant and the heat dissipation surface, significantly improving heat exchange efficiency and meeting the heat dissipation requirements of high power density.

[0014] The heat dissipation device manufactured using this method adopts an integrated packaging solution, which is lightweight, compact, and easy to integrate and install. Furthermore, the nano-injection molding integrated packaging eliminates the leakage risk of traditional welding or mechanical seals, resulting in a high pass rate in airtightness tests. The manufacturing process of this method is highly compatible: the process flow of extrusion molding + cutting + nano-surface treatment + two injection molding is compatible with existing mass production equipment, making it suitable for large-scale mass production. The nano-injection molding integrated packaging eliminates the leakage risk of traditional welding or mechanical seals, resulting in a high pass rate in airtightness tests.

[0015] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of an embodiment of the present invention.

[0017] Figure label: 10. Heat sink plate 11. Water inlet end 12. Water outlet 101, first water passage 102. Second water passage; 103. Third water passage 20. Water inlet assembly; 21. First connector 22. First mounting component; 211. First main body. 212. First blocking part; 213. First sealing part 201. Water inlet space; 202. Second water passage space 221. Water inlet; 222. Water inlet pipe 30. Water outlet assembly; 31. Second connector 32. Second mounting component; 311. Second main body. 312. Second blocking part; 313. Second sealing part 301. First water passage space; 302. Water outlet space 321. Water outlet; 322. Water outlet pipe. Detailed Implementation

[0018] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0019] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0020] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this application.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0022] Please see Figure 1 As shown, this application provides a liquid cooling heat dissipation device, including a heat dissipation plate 10, having a water inlet end 11 and a water outlet end 12. The water inlet end 11 is provided with a water inlet component 20 communicating with the water inlet end 11. A water inlet space 201 and a second water passage space 202 are formed between the water inlet component 20 and the water inlet end 11. The water outlet end 12 is provided with a water outlet component 30 communicating with the water outlet end 12. A first water passage space 301 and a water outlet space 302 are formed between the water outlet component 30 and the water outlet end 12. The heat sink 10 has multiple water passages 101, 102, and 103 that connect the inlet 11 and outlet 12. Water enters from the inlet assembly and flows sequentially through the inlet space 201, the first water passage 101, the first water passage 301, the second water passage 102, the second water passage 202, the third water passage 103, and the outlet space 302 before exiting from the outlet assembly 30. Figure 1 As indicated by the arrows in the middle of the water flow, the entire water flow is arranged in an inverted S shape. Compared with the traditional direct flow channel, the heat dissipation device of this application increases the contact area between the refrigerant and the heat dissipation surface, significantly improving the heat exchange efficiency and meeting the heat dissipation requirements of high power density.

[0023] For example, the heat sink 10 has an organ tube structure and is made of aluminum alloy (preferably 6063 or 6061 aluminum alloy) by extrusion molding process, with a cross-section of a porous flat tube (organ tube) structure.

[0024] In one embodiment, the first water passage 101 is centrally located inside the heat sink 10, the second water passage 102 is located outside the first water passage 101, and the third water passage 103 is located outside the second water passage 102; one end of the first water passage 101 is connected to the water inlet space 201, and the other end is connected to the middle position of the first water passage space 301; one end of the second water passage 102 is connected to the outside of the first water passage space 301, and the other end is connected to the inside of the second water passage space 202; one end of the third water passage 103 is connected to the outside of the second water passage space 202, and the other end is connected to the water outlet space 302. The entire flow channel splits from the middle to both sides. The low-temperature refrigerant is injected from the center and flows synchronously to both sides in two separate paths. The temperature rise of the left and right channels is synchronous and symmetrical, thus offsetting the temperature difference. The central region is the coldest medium, and the temperature rise of both sides is synchronous. The high and low temperature regions of the entire heat exchange surface complement each other, and the overall temperature difference can be reduced by more than 70%, with the temperature difference controlled within 2-3℃. Moreover, the length and resistance of the left and right channels are completely consistent, and the refrigerant is evenly distributed.

[0025] The system comprises four first water inlets 101, with four main inlets in the center simultaneously distributing low-temperature refrigerant to both sides. The flow rates of the two fluid streams are perfectly symmetrical, preventing any imbalance in flow rate on one side. Four second water inlets 102 are also present, with each pair of second water inlets located on either side of the first water inlets 101. Two independent water inlets on each side further divide the flow, splitting the large central flow into four medium-flow streams. Eight third water inlets 103 are evenly distributed on both sides of the second water inlets 102. Each pair of second water inlets branches into four third water inlets 103, breaking down the refrigerant into numerous small tributaries that cover the entire heat exchange plate surface. This arrangement of water inlets, with its layered diffusion structure of four main inlets in the center → two branch channels on each side → four outlets at each end, results in extremely uniform flow, eliminating flow deviation and cooling blind spots.

[0026] The water inlet assembly 20 includes a first connector 21 and a first mounting member 22 disposed on the outside of the first connector 21. The first connector 21 includes a first main body 211, two first blocking parts 212 extending inward from the inner wall of the first main body 211 and arranged at intervals, and a first sealing part 213 extending inward from both ends of the first main body 211. The two first blocking parts 212 are respectively connected to the walls of the corresponding first water passages 101, and the two first blocking parts 212 change the direction of water flow; the two first sealing parts 213 respectively seal the two sides of the water inlet end 11, and the first sealing parts 213 block the two sides of the heat dissipation plate to prevent water leakage; the water inlet space 201 is formed between the inner wall of the first main body 211 and the two first blocking parts 212; the second water passage space 202 is formed between the inner wall of the first main body 211 and one of the first blocking parts 212 and one of the first sealing parts 213; the first mounting member 22 is provided with a water inlet 221 and a water inlet pipe 222, one end of the water inlet pipe 222 is connected to the water inlet 221, and the other end is connected to the water inlet space 201.

[0027] For example, the water inlet pipe 222 and the first connector 21 are placed in the first mold for injection molding, so that the water inlet pipe 222 and the first connector 21 are integrally injection molded and connected to form a primary injection molded assembly. Then, the primary injection molded assembly is placed in the second mold for injection molding to form the first mounting part 22. The primary injection molded part is made of PBT or PPS engineering plastic to form the end cap or side wall structure of the liquid cooling heat sink, which serves to seal, guide, and position the two ends of the heat sink.

[0028] The water outlet assembly 30 includes a second connector 31 and a second mounting member 32 disposed on the outside of the second connector 31. The second connector 31 includes a second main body 311, two second blocking parts 312 extending inward from the inner wall of the second main body 311 and spaced apart, and second capping parts 313 extending inward from both ends of the second main body 311. The two second blocking parts 312 are respectively connected to the walls of the corresponding second water passages 102, and the distance between the two second blocking parts 312 is greater than the distance between the two first blocking parts 212. For example, both the first blocking part 212 and the second blocking part 312 are provided with grooves, and the walls of the first water passages 101 or the second water passages 102 are inserted into the grooves and bonded. The two second capping parts 313 respectively cover the two sides of the water outlet end 12.

[0029] The first water passage space 301 is formed between the inner wall of the second main body 311 and the two second blocking parts 312; the water outlet space 302 is formed between the inner wall of the second main body 311 and the corresponding second blocking part 312 and the corresponding second sealing part 313; the second mounting member 32 is provided with a water outlet 321 and a water outlet pipe 322, one end of the water outlet pipe 322 is connected to the water outlet 321, and the other end is connected to the water outlet space 302.

[0030] For example, there are two water outlet pipes 322, which are arranged in a figure-eight shape, with the water outlet ends converging towards the water outlet to accelerate the water flow speed.

[0031] The first mounting component 22 is integrally molded and connected to the water inlet end 11; the second mounting component 32 is integrally molded and connected to the water outlet end 12. The first and second mounting components structurally encapsulate the water inlet and outlet ends, providing good mechanical strength and dimensional accuracy. The seamless, integrated injection molding eliminates the need for additional seals, ensuring reliable flow channel sealing. Furthermore, the integrated encapsulation solution is lightweight, compact, and easy to integrate and install. The injection-molded integrated encapsulation structure eliminates the leakage risk associated with traditional welding or mechanical seals, resulting in a high airtightness test pass rate.

[0032] A method for preparing a liquid cooling heat dissipation device includes the following steps: (1) Heat sink extrusion molding: Aluminum alloy profiles with a multi-hole flat tube cross section are prepared by extrusion molding machine. The wall thickness, hole shape and outer dimensions are controlled to ensure that the cross section of each water passage is uniform. For example, the aluminum alloy profiles with multi-hole flat tubes are aluminum alloy bellows tubes, and 6063 or 6061 aluminum alloy ingots are selected. (2) Heat sink plate cutting: According to the design dimensions of heat sink plate 10, the extruded aluminum alloy profile is precisely cut to form the first water passage 101, the second water passage 102 and the third water passage 103 inside, and the end face is flat, burrs are removed, and dimensional accuracy is guaranteed. (3) Surface treatment: The surface of the cut heat sink 10 is chemically etched or nano-etched to form a uniform and dense nanoscale microporous structure on the surface of the heat sink 10. After treatment, it is cleaned and dried, and the surface cleanliness is strictly controlled to prevent secondary pollution. For example, the pore size of the microporous structure is 20-100nm and the depth is 100-300nm. (4) One-time injection molding: The water inlet pipe 222 and the water outlet pipe 322 are pre-placed in the one-time injection mold. The mold is closed and the plastic is injected to form the first connector 21 and the second connector 31. The first connector 21 and the water inlet pipe 222 are injection molded to form the first injection molded assembly. The second connector 31 and the water outlet pipe 322 are injection molded to form the second injection molded assembly. For example, the water inlet pipe 222 is made of aluminum alloy or stainless steel. The injection plastic is PBT or PPS engineering plastic, and it is molded under the set temperature (PBT: 240~260℃; PPS: 310~340℃) and pressure of the injection molding machine. The engineering plastic (PBT / PPS) shell provides excellent electrical insulation performance to meet the safety requirements of high-voltage power battery and other application scenarios. (5) Flow channel bonding: Apply high-temperature resistant structural adhesive to the designated positions of the water inlet end 11 and water outlet end 12 of the heat sink 10, and bond the first injection molding assembly to the water inlet end 11, with a water inlet space 201 and a second water passage space 202 separated between the first injection molding assembly and the water inlet end 11; bond the second injection molding assembly to the water outlet end 12, with a first water passage space 301 and a water outlet space 302 separated between the second injection molding assembly and the water outlet end 12; after the flow channel is assembled, the water flows sequentially through the water inlet space 201, the first water passage channel 101, the first water passage space 301, the second water passage channel 102, the second water passage space 202, the third water passage channel 103 and the water outlet space 302; after bonding, perform curing and air tightness testing to ensure that there is no leakage in the flow channel. For example, the test pressure is ≥0.3MPa and the pressure holding time is ≥30s; (6): Secondary injection molding: The bonded workpiece is placed into a secondary injection mold for nano-injection molding. The mold is closed and the glue is injected. The first mounting part 22 is injection molded on the surface of the water inlet 11, and the second mounting part 32 is injection molded on the surface of the water outlet 12. The first mounting part 22 and the second mounting part 32 are injection molded together with the microporous structure to obtain a complete liquid cooling heat dissipation device. The nano-injection molding process realizes a high-strength integrated bond between aluminum alloy and engineering plastic (bonding force ≥15MPa). No additional sealing parts are required. The overall structure has high reliability. The integrated packaging scheme is lightweight, compact, and easy to integrate and install. (7): Finished product inspection: Perform appearance inspection, dimensional inspection, airtightness test, insulation resistance test, bonding strength test, refrigerant corrosion resistance test, etc. on the finished products. Qualified products are put into storage.

[0033] The heat dissipation device made using this preparation method adopts an integrated packaging solution, which is lightweight, compact, and easy to integrate and install. Furthermore, the nano-injection molding integrated packaging eliminates the leakage risk of traditional welding or mechanical seals, and the airtightness test pass rate is high.

[0034] The preparation method has strong manufacturing process compatibility: the process flow of extrusion molding + cutting + nano surface treatment + two injection molding is compatible with existing mass production equipment and is suitable for large-scale mass production; the nano injection molding integrated packaging eliminates the leakage risk of traditional welding or mechanical seals and has a high airtightness test pass rate.

[0035] In one embodiment of this application, step (3) surface treatment includes the following steps: (3.1) Degreasing Treatment: The cut heat sink 10 is sequentially placed into an ultrasonic pre-degreasing device and an ultrasonic main degreasing device for two ultrasonic degreasing processes. The environmentally friendly degreasing solution in the ultrasonic pre-degreasing device and the ultrasonic main degreasing device performs ultrasonic degreasing on the heat sink 10 under the action of ultrasound, removing oil and dirt from the surface of the product. For example, the degreasing solution is based on 1000L of tank liquid. First, add clean water to 80% of the treatment tank and heat it to about 35°C. Then, slowly add 20kg of FC-E2011AC (powder) and 7kg of FC-2011B agent (liquid) while stirring and dissolving. Then, add clean water to 1000L. Next, heat to the specified treatment temperature and then confirm the free alkalinity. The environmentally friendly degreasing agent used is free of phosphorus and nitrogen; the B agent is liquid with good biodegradability of the active agent; it has low COD, reducing wastewater treatment costs; and it operates at low temperature (38-45°C), saving energy and reducing consumption.

[0036] (3.2) Cleaning 1: Place the heat sink 10, which has been cleaned by ultrasonic cleaning, into the corresponding water washing tank for two-stage overflow cleaning and rinsing; the pH value of the cleaning tap water is 8-10, and the tap water overflows during the cleaning process, and the water washing time is 20-35 seconds; use weakly alkaline water to clean the heat sink twice to remove the dirt attached to the heat sink. (3.3) Activation: The heat sink 10 after cleaning 1 is placed in an activation tank to react with the activation solution, removing surface oxides and organic matter, and generating micron-sized pits on the surface of the heat sink 10; the activation solution dissolves the natural dense Al2O3 passivation film on the aluminum surface, slightly roughens the surface, and provides nano-nucleation sites; for example, the activation solution is a mixture of LF029P2 activator and water, and LF029P2 activator accounts for 68% of the activation solution. Activation solution pH: 0.7-1.8, total acidity: 1226, activation reaction time: 1 min.

[0037] (3.4) Roughening: The activated heat sink 10 is placed in a roughening solution for surface roughening, and primary nanopores are formed on the surface of the heat sink 10. The roughening solution formula is the roughening solution used in our company's patent CN118910693B. Specifically, the roughening solution is: 1000mL of deionized water as solvent, wherein 120-125g ammonium fluoride, 25-28g ammonium chloride, 2-3g copper chloride, 1-2g polyethylene glycol, 0.5-0.7g sodium gluconate, 6-7g boric acid, 5-6g glycerol, and 1-2g γ-(2,3-epoxypropoxy)propyltrimethoxysilane; (3.5) Cleaning 2: Place the heat sink 10 after the roughening reaction is completed into the corresponding water washing tank for three-stage overflow deionized water rinsing; the three-stage overflow uses tap water and pure water for cleaning to remove the stains generated by activation (surface oxide) and roughening, and prevent dirt from clogging the first-stage nanopores and affecting the subsequent anodizing process. (3.6) Anodizing treatment: Electrochemical treatment is performed on the surface of the heat sink 10 after cleaning 2 to form an oxide film layer and secondary nano-sized pores on the surface of the heat sink 10; The electrolyte used in this step is the electrolyte used in our company's patent CN118910693B; Specifically, 100mL of deionized water is used as the solvent, wherein 0.1-0.15g of silica-POSS composite, 1-1.3g of titanium dioxide-silica composite sol, 1.2-1.5g of sulfuric acid, and 5-6g of disodium ethylenediaminetetraacetate; (3.7) Cleaning 3: After anodizing, the heat sink 10 is subjected to rough cleaning, spraying, and pure water immersion in sequence; the conductivity of pure water is controlled to be ≤5μS / cm to prevent salt ion residue from causing bubbling after injection molding.

[0038] (3.8) Low temperature drying: After cleaning 3, the heat sink 10 is dried in a hot air environment of 60-70℃ for 5-8 minutes. Baking at >100℃ is prohibited: High temperature will cause the alumina on the inner wall of the nanopore to shrink and close, which will greatly reduce the bonding force.

[0039] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A liquid cooling heat dissipation device, characterized in that: The device includes a heat sink with an inlet end and an outlet end. The inlet end is provided with an inlet component that connects to the inlet end, and an inlet space and a second water passage space are formed between the inlet component and the inlet end. The outlet end is provided with an outlet component that connects to the outlet end, and a first water passage space and an outlet space are formed between the outlet component and the outlet end. The heat sink has multiple water passages, including a first water passage, a second water passage, and a third water passage, which connect the water inlet and the water outlet. The water flows sequentially through the water inlet space, the first water passage, the first water passage space, the second water passage, the second water passage space, the third water passage, and the water outlet space.

2. The liquid cooling heat dissipation device according to claim 1, characterized in that: The first water passage is centrally located inside the heat sink, the second water passage is located outside the first water passage, and the third water passage is located outside the second water passage. One end of the first water passage is connected to the water inlet space, and the other end is connected to the middle of the first water passage space. One end of the second water passage is connected to the outside of the first water passage space, and the other end is connected to the inside of the second water passage space. One end of the third water passage is connected to the outside of the second water passage space, and the other end is connected to the water outlet space.

3. The liquid cooling heat dissipation device according to claim 2, characterized in that: The number of first water passages is four, the number of second water passages is four, and each pair of second water passages is located on both sides of the first water passage; the number of third water passages is eight, and the eight third water passages are evenly distributed on both sides of the second water passage.

4. The liquid cooling heat dissipation device according to claim 1, characterized in that: The water inlet assembly includes a first connector and a first mounting component disposed on the outside of the first connector. The first connector includes a first main body, two first blocking portions extending inward from the inner wall of the first main body and spaced apart, and first capping portions extending inward from both ends of the first main body. The two first blocking portions are respectively connected to the walls of the corresponding first water passages. The two first capping portions respectively cover the two sides of the water inlet end. The water inlet space is formed between the inner wall of the first main body and the two first blocking portions. The second water passage space is formed between the inner wall of the first main body and one of the first blocking portions and one of the first capping portions. The first mounting component is provided with a water inlet and a water inlet pipe, one end of the water inlet pipe being connected to the water inlet and the other end being connected to the water inlet space.

5. The liquid cooling heat dissipation device according to claim 4, characterized in that: The water outlet assembly includes a second connector and a second mounting member disposed on the outside of the second connector. The second connector includes a second main body, two second blocking parts extending inward from the inner wall of the second main body and spaced apart, and second capping parts extending inward from both ends of the second main body. The two second blocking parts are respectively connected to the walls of the corresponding second water passages, and the distance between the two second blocking parts is greater than the distance between the two first blocking parts. The two second capping parts respectively cover the two sides of the water outlet end. The first water passage space is formed between the inner wall of the second main body and the two second blocking parts; the water outlet space is formed between the inner wall of the second main body and the corresponding second blocking part and the corresponding second sealing part; the second mounting member is provided with a water outlet and a water outlet pipe, one end of the water outlet pipe is connected to the water outlet and the other end is connected to the water outlet space.

6. The liquid cooling heat dissipation device according to claim 5, characterized in that: Both the first and second blocking parts are provided with grooves, and the wall of the first or second water passage is inserted into the groove and bonded.

7. The liquid cooling heat dissipation device according to claim 5, characterized in that: The first mounting component is integrally formed and connected to the water inlet end; the second mounting component is integrally formed and connected to the water outlet end.

8. A method for preparing a liquid-cooled heat dissipation device, characterized in that, Includes the following steps: (1) Extrusion molding of heat dissipation plate: Aluminum alloy profiles with a multi-hole flat tube cross section are prepared by extrusion molding machine. The wall thickness, hole shape and outer dimensions are controlled to ensure that the cross section of each water passage is uniform. (2) Heat sink plate cutting: According to the design dimensions of the heat sink plate, the extruded aluminum alloy profile is precisely cut to form the first water passage, the second water passage and the third water passage inside, and the end face is flat, burrs are removed, and dimensional accuracy is guaranteed. (3) Surface treatment: Chemical etching or nano-etching is performed on the surface of the cut heat sink to form a uniform and dense nano-scale microporous structure on the surface of the heat sink. After treatment, the surface is cleaned and dried, and the surface cleanliness is strictly controlled to prevent secondary pollution. (4) One-time injection molding: The water inlet pipe and the water outlet pipe are pre-placed in the one-time injection mold, the mold is closed and the glue is injected to form the first connector and the second connector. The first connector and the water inlet pipe are injection molded to form the first injection assembly, and the second connector and the water outlet pipe are injection molded to form the second injection assembly. (5) Flow channel bonding: Apply high-temperature resistant structural adhesive to the designated positions at the water inlet and water outlet of the heat sink, bond the first injection molding assembly to the water inlet, and form a water inlet space and a second water passage space between the first injection molding assembly and the water inlet; bond the second injection molding assembly to the water outlet, and form a first water passage space and a water outlet space between the second injection molding assembly and the water outlet; after the flow channel is assembled, the water flows sequentially through the water inlet space, the first water passage channel, the first water passage space, the second water passage channel, the second water passage space, the third water passage channel and the water outlet space; after bonding, perform curing and airtightness testing to ensure that there is no leakage in the flow channel; (6): Secondary injection molding: The bonded workpiece is placed into a secondary injection mold for nano-injection molding, the mold is closed and the glue is injected. The first mounting part is injection molded on the surface of the water inlet end, and the second mounting part is injection molded on the surface of the water outlet end. The first and second mounting parts are injection molded together with the microporous structure to obtain a complete liquid cooling heat dissipation device. (7): Finished product inspection: Perform appearance inspection, dimensional inspection, airtightness test, insulation resistance test, bonding strength test, refrigerant corrosion resistance test, etc. on the finished products. Qualified products are put into storage.

9. The method for preparing the liquid cooling heat dissipation device according to claim 8, characterized in that: Step (3) Surface treatment includes the following steps: (3.1) Degreasing treatment: The cut heat sink is placed into the ultrasonic pre-degreasing device and the ultrasonic main degreasing device in sequence for two ultrasonic degreasing processes. The environmentally friendly degreasing liquid in the ultrasonic pre-degreasing device and the ultrasonic main degreasing device performs ultrasonic degreasing on the heat sink under the action of ultrasound, removing oil and dirt from the surface of the product. (3.2) Cleaning 1: Place the heat sink plate that has been ultrasonically cleaned into the corresponding water washing tank for two-stage overflow cleaning and rinsing; (3.3) Activation: The heat sink plate after cleaning 1 is placed in the activation tank to react with the activation liquid, removing surface oxides and organic matter, and generating micron-level pits on the surface of the heat sink plate; (3.4) Roughening: The activated heat sink is placed in a roughening solution for surface roughening, and primary nanopores are formed on the surface of the heat sink. (3.5) Cleaning 2: Place the heat sink after the roughening reaction is completed into the corresponding water washing tank for three-stage overflow deionized water rinsing; (3.6) Anodizing: The surface of the heat sink after cleaning 2 is anodized to form an oxide film layer and secondary nano-sized pores on the surface of the heat sink; (3.7) Cleaning 3: The heat sink after anodizing is subjected to rough cleaning, spraying, and soaking in pure water in sequence; (3.8) Low temperature drying: The heat sink after cleaning 3 is dried in a hot air environment of 60-70℃ for 5-8 minutes.

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