阅读说明：本技术 一种自密接型超疏气浸没式相变液冷强化散热板及其制备方法和应用 (Self-sealing type super-gas-dredging immersion type phase-change liquid-cooling reinforced heat dissipation plate and preparation method and application thereof ) 是由 江雷 白春礼 田野 徐哲 于 2021-07-07 设计创作，主要内容包括：本发明公开一种自密接型超疏气浸没式相变液冷强化散热板,所述强化散热板表面包括第一区域和第二区域；第一区域内强化散热板表面分布有微米乳突阵列,第二区域内强化散热板表面分布有微米乳突阵列,且微米乳突阵列间隙内封装有液态金属；其中,强化散热板与发热器件的接触区域包括第二区域。该强化散热板的第一区域包括大面积超疏气强化沸腾结构,能显著促进液-气相变,提升液冷散热性能；第二区域具有空隙自填充型密接功能,能够大幅减少与发热器件的接触热阻,提高界面导热效率。同时,该强化散热板成本低廉、装卸便捷、性能稳定、制备工艺简单,在数据中心服务器、航天热控装备、先进动力电池等领域的具有良好的应用前景。(The invention discloses a self-sealing type super-gas-dredging immersion type phase-change liquid cooling reinforced cooling plate, wherein the surface of the reinforced cooling plate comprises a first area and a second area; the surface of the enhanced radiating plate in the first area is distributed with a micrometer mastoid array, the surface of the enhanced radiating plate in the second area is distributed with a micrometer mastoid array, and liquid metal is sealed in gaps of the micrometer mastoid array; the contact area of the reinforced heat dissipation plate and the heating device comprises a second area. The first area of the reinforced heat dissipation plate comprises a large-area super-gas-dredging reinforced boiling structure, so that liquid-gas phase change can be remarkably promoted, and the liquid cooling heat dissipation performance is improved; the second area has a gap self-filling type sealing function, so that the contact thermal resistance with a heating device can be greatly reduced, and the interface heat conduction efficiency is improved. Meanwhile, the reinforced heat dissipation plate is low in cost, convenient to assemble and disassemble, stable in performance and simple in preparation process, and has good application prospects in the fields of data center servers, aerospace thermal control equipment, advanced power batteries and the like.)

1. A self-sealing type super-hydrophobic immersion type phase change liquid cooling enhanced cooling plate is characterized in that the surface of the enhanced cooling plate comprises a first area and a second area; the surface of the enhanced radiating plate in the first area is distributed with a micrometer mastoid array, the surface of the enhanced radiating plate in the second area is distributed with a micrometer mastoid array, and liquid metal is sealed in gaps of the micrometer mastoid array; the contact area of the reinforced heat dissipation plate and the heating device comprises a second area.

2. The self-sealing type super-hydrophobic immersion type phase change liquid cooling enhanced cooling panel as claimed in claim 1, wherein the micro mastoid is cone-shaped or column-shaped;

preferably, the height of the micrometer mastoid is 5-500 μm, the equivalent diameter is 10-1000 μm, and the distance between adjacent micrometer mastoids is 10-1000 μm;

preferably, the micro mastoid surface has a nano-fold topography;

preferably, the thickness of the nano-folds is 5nm to 500 nm.

3. The self-sealing super-hydrophobic immersed phase-change liquid-cooled reinforced heat dissipation plate as recited in claim 1, wherein the surface of the micro mastoid array has special wettability, and wherein the super-hydrophobic property of the surface of the micro mastoid in the first region is less than 20 μ N for the adhesion force of the super-hydrophobic property to bubbles under liquid; the second region of the super-parent liquid metal on the surface of the micrometer mastoid has a static contact angle of less than 10 degrees to the liquid metal droplet in air or oxygen-free environment.

4. The self-sealing type super-hydrophobic immersion type phase change liquid cooling enhanced cooling plate as claimed in claim 1, wherein an isolation zone is present between the first region and the second region;

preferably, the size of the distributed micro mastoid arrays in the first and second regions is different.

5. The self-sealing type super-hydrophobic immersion type phase-change liquid cooling enhanced cooling plate as claimed in claim 1, wherein the area of a contact area of the enhanced cooling plate and a heating device is not less than the area of the second area;

preferably, the interstices of the second area of the array of micro mastoids are entirely filled with liquid metal.

6. The self-sealing type super-hydrophobic immersion type phase change liquid cooling enhanced cooling plate as claimed in claim 1, wherein the melting point of the liquid metal is higher than room temperature but lower than the stable operation temperature of the heat generating device; preferably, the liquid metal is selected from gallium, indium, tin, bismuth or alloys thereof, or doped mixtures thereof with other metals, oxides of other metals, non-metals or non-metal oxides; the other metal is selected from copper, aluminum, gold, silver, tungsten, rhodium or iridium, and the nonmetal is carbon or silicon.

7. A method for preparing the self-sealing type super-hydrophobic immersion type phase-change liquid cooling reinforced cooling plate as claimed in any one of claims 1 to 6, comprising the following steps: integral forming of the reinforced radiating plate, etching of the surface of the reinforced radiating plate to form a micrometer mastoid array, regulation and control of the infiltration property of the micrometer mastoid array and packaging of liquid metal in the second area.

8. The preparation method of claim 7, wherein the etching method for forming the micrometer mastoid array on the surface of the enhanced heat dissipation plate by etching is laser integrated etching; preferably, the method for regulating the infiltration property of the micrometer mastoid array comprises chemical reagent modification, functional medium deposition, thermal modification, plasma treatment, ozone treatment or ultraviolet irradiation.

9. The method of claim 7, wherein the liquid metal encapsulation in the second region comprises the steps of: preheating the reinforced heat dissipation plate, then infiltrating and filling the molten liquid metal into the gaps of the micrometer mastoid array in the second area, and then cooling and solidifying to finish the packaging of the liquid metal.

10. The application of the self-sealing type ultra-hydrophobic immersion type phase-change liquid cooling enhanced cooling plate as claimed in any one of claims 1 to 6 in the fields of data center servers, aerospace thermal control equipment and advanced power batteries.

Technical Field

The invention relates to the technical field of heat dissipation equipment. More particularly, the invention relates to a self-sealing type super-hydrophobic immersed phase-change liquid cooling strengthened heat dissipation plate.

Background

With the progress and development of the microelectronic industry, the cooling and heat dissipation requirements for high-heating-density devices are increasing year by year, and the immersion type phase-change liquid cooling technology is expected to become a main heat dissipation mode in the fields of future data center servers (application publication number CN 104597994A, CN 106774741 a), aerospace thermal control equipment (application publication number CN 110213934A, CN 112013427 a), advanced power batteries (application publication number CN 110729526A, CN 111883876A) and the like instead of the traditional air cooling means of cooling by air.

The immersion type phase change liquid cooling is a heat dissipation technology which completely immerses a solid heating device (heat source) into a liquid refrigerant medium (such as water, a refrigerant of a fluorinated liquid and the like) and realizes cooling by latent heat absorption of liquid-gas phase change of the refrigerant medium evaporation or boiling and the like, and the heat transmission (namely, heat dissipation efficiency) of a unit volume can be improved by 3500 times compared with air cooling. However, a high heat generation density (heat flux density 100W/cm) is required²Above) the cooling and heat dissipation requirements of devices (application publication No. CN 112188808A, CN 111352489 a) still present significant challenges.

The configuration of the enhanced heat dissipation component has been shown to further improve the immersed phase change liquid cooling efficiency, with plate type components (may be referred to as "enhanced heat dissipation plates") being the most common. As a tie for connecting the heating device and the refrigerant medium, the bottom surface of the reinforced heat dissipation plate is usually in direct contact with the heating device or forms a package, and other parts are completely immersed by the refrigerant medium, so that the phase-change liquid cooling is reinforced by guiding heat transfer and increasing the heat exchange area. According to the above principle, it is the main design direction of the reinforced heat dissipation plate to reduce the contact thermal resistance with the heating device and promote the liquid-gas phase change of the refrigerant medium. However, the enhanced heat dissipation component reported at present is not related to enhancing the coolant boiling by utilizing the surface of sintered copper particles (application publication No. CN 107894823 a), and the problem of thermal contact resistance of heat generating device has not been noticed, and the latter usually requires additional thermal interface materials (such as thermal grease, thermal gasket, thermal paste, phase change material, graphite sheet, etc.). However, even the most advanced liquid metal thermal interface materials at present (application publication No. CN 106929733A, CN 107052308A, CN 110330943 a), the thermal conductivity has not exceeded 100W m^{- 1}K^-1Far below that of solid metal materials (e.g. copper thermal conductivity of about 400W) m^-1K^-1). Such peripheral thermal interfaces not only increase costs, but also introduce assembly difficulties and operational and maintenance risks: air at the contact interface cannot be completely excluded once the assembly process is complete (thermal conductivity is only about 0.024 Wm)^-1K^-1) The thermal resistance is greatly increased, and cooling and heat dissipation are retarded; once the complex components (without conductive metal doped particles) in the thermal interface gradually run off and enter the refrigerant medium, the properties of the refrigerant are damaged, the liquid cooling energy efficiency is reduced, and the short circuit of electronic devices and even the system paralysis are caused. In addition, the existing scheme for strengthening the heat dissipation of the sintered copper particles (application publication number CN 107894823 a) has the disadvantages of complicated process, high energy consumption, limited actual processing area, lack of precise control on structure and morphology, and the like.

Therefore, it is desirable to provide a reinforced heat dissipation plate with a large area of super-hydrophobic reinforced boiling structure, which can greatly reduce thermal contact resistance and improve interface heat conduction efficiency.

Disclosure of Invention

One object of the present invention is to provide a self-sealing type super-hydrophobic immersion type phase-change liquid-cooled reinforced heat dissipation plate, wherein a first region of the reinforced heat dissipation plate comprises a large-area super-hydrophobic reinforced boiling structure, which can significantly promote liquid-gas phase change and improve liquid-cooled heat dissipation performance; the second area has a gap self-filling type sealing function, so that the contact thermal resistance with a heating device can be greatly reduced, and the interface heat conduction efficiency is improved.

The invention also aims to provide a preparation method of the self-sealing type super-hydrophobic immersion type phase-change liquid cooling strengthened heat dissipation plate.

The invention further aims to provide application of the self-sealing type super-hydrophobic immersed phase-change liquid cooling strengthened heat dissipation plate.

The immersed phase-change liquid cooling means that the heating device is completely immersed in a liquid refrigerant medium, and the characteristics of low boiling point and high latent heat of the refrigerant medium are utilized, so that the liquid-gas phase-change latent heat is absorbed to continuously transfer heat during boiling, and the cooling effect is achieved.

The reinforced heat dissipation plate is a plate type heat dissipation part suitable for an immersed phase-change liquid cooling scene, is usually arranged between a heating device and a cold medium, the bottom of the reinforced heat dissipation plate is directly contacted with the heating device or forms a package, other parts of the reinforced heat dissipation plate are completely immersed by the cold medium, and the reinforced heat dissipation plate promotes the latent heat absorption of liquid-gas phase change by guiding heat transfer and increasing the heat exchange area.

High heat density (heat flux density 100W/cm) in the prior art²Above) the immersion type phase transition liquid cooling of electronic device, the heat dissipation enhancing component that uses can't compromise contact heat conduction and phase transition heat transfer. Aiming at the technical defects, the invention provides the reinforced heat dissipation plate which is provided with a self-filling high-thermal-conductivity close connection region and a large-area super-gas-dredging reinforced boiling structure, and the invention synergistically considers the reduction of contact thermal resistance and the promotion of liquid-gas phase change, and provides a brand-new optimized solution for the immersed phase-change liquid cooling reinforced heat dissipation.

In order to achieve the purpose, the invention adopts the following technical scheme:

a self-close-connection type super-gas-dredging immersion type phase-change liquid-cooling reinforced heat dissipation plate is disclosed, wherein the surface of the reinforced heat dissipation plate comprises a first area and a second area; the surface of the enhanced radiating plate in the first area is distributed with a micrometer mastoid array, the surface of the enhanced radiating plate in the second area is distributed with a micrometer mastoid array, and liquid metal is sealed in gaps of the micrometer mastoid array; the contact area of the reinforced heat dissipation plate and the heating device comprises a second area.

The surface of the reinforced heat dissipation plate comprises a first area and a second area, wherein the contact area of the reinforced heat dissipation plate and the heating device comprises the second area. After the reinforced heat dissipation plate and the heating device are tightly assembled, the internally packaged liquid metal which is in a solid state at normal temperature is heated and melted, quickly and uniformly infiltrates and automatically and completely fills gaps (air is removed) at the interface, the contact thermal resistance is reduced, the heat conduction efficiency is improved, and the temperature equalizing rate of the solid-liquid phase change of the liquid metal in the second area is more than 1cm²(s) obtaining a material close to the main body of the enhanced heat sink (e.g. copper, thermal conductivity about 400W m^-1K^-1) The ultra-high thermal conductivity; the micron mastoid array distributed in the first area can provide a vaporization nucleation site with an ultra-large area as a reinforced boiling structure, promote liquid-gas phase change and improve liquid cooling performance.

Preferably, the micro papilla is conical or cylindrical;

preferably, the height of the micrometer mastoid is 5-500 μm, the equivalent diameter is 10-1000 μm, and the distance between adjacent micrometer mastoids is 10-1000 μm.

Preferably, the height of the single micrometer mastoid is 10-400 μm, the equivalent diameter is 30-800 μm, and the distance between adjacent micrometer mastoids is 30-800 μm.

More preferably, the height of the individual micrometer mastoids is 30 to 300 μm, the equivalent diameter is 50 to 500 μm, and the distance between adjacent micrometer mastoids is 50 to 500 μm.

Further preferably, the height of the single micrometer mastoid is 50 μm to 200 μm, the equivalent diameter is 100 μm to 200 μm, and the distance between the adjacent micrometer mastoids is 100 μm to 200 μm.

The height of the micrometer mastoid determines the thickness of the liquid metal packaged in the micrometer mastoid array gap, and the liquid metal with the thickness of 5-500 mu m can be obtained based on the process technology, which is the ultrathin thickness which can not be realized by the traditional thermal interface, so the material is economical, and the cost is lower.

The spacing between adjacent papillae is 10 μm to 1000 μm, which, as will be appreciated by those skilled in the art, determines the size of the gaps in the array of papillae.

Preferably, the micro mastoid surface has a nano-fold topography;

the micro mastoid with the nano-fold shape has larger specific surface area, more vaporization cores, smaller bubble movement retardation and stronger boiling strengthening effect, promotes liquid-gas phase change and improves the liquid cooling performance.

Preferably, the thickness of the nano-folds is 5nm to 500 nm. For example, the thickness of the nanopatterned layer includes, but is not limited to, 10nm to 400nm, 30nm to 300nm, or 10nm to 200nm, etc.

Preferably, the surface of the micrometer mastoid array has special wettability, wherein the surface of the micrometer mastoid in the first area is super-hydrophobic, and the adhesion force to bubbles under liquid is less than 20 μ N, so as to ensure that phase-change bubbles are quickly separated; the second area micro mastoid surface super-affinity liquid metal has a static contact angle of less than 10 degrees to liquid metal microdroplets in air or oxygen-free environment, so that the liquid metal is easy to uniformly spread into a thin layer after infiltrating the surface of the micro mastoid array, and stable packaging of the liquid metal is guaranteed.

Preferably, a separation zone is present between the first and second regions. The isolation strip can prevent the liquid metal in the second area from leaking to the first area along the gap.

Preferably, the size of the distributed micro mastoid arrays in the first and second regions is different. The size of the micrometer mastoid array in the first area mainly influences the enhanced boiling effect, the size of the micrometer mastoid array in the second area mainly determines the contact thermal resistance of the enhanced heat dissipation plate and the heating device, and in the practical application process, the sizes of the micrometer mastoid arrays distributed in the first area and the second area can be set according to requirements, and the sizes of the micrometer mastoid arrays can be the same or different.

Preferably, the array of micro mastoids within the first region may have different sizes. One possible embodiment is that the size of the micro mastoid array in different parts of the first area may be designed according to specific requirements, and the specific form is not limited in the art.

Preferably, the area of the contact area between the strengthened heat dissipation plate and the heat generating device is not less than the area of the second area, that is, the area of the contact area between the strengthened heat dissipation plate and the heat generating device is greater than or equal to the area of the second area, and the liquid metal must be located in the contact area.

Preferably, the melting point of the liquid metal is higher than room temperature but lower than the stable operating temperature of the heat generating device; therefore, the liquid metal is solid at normal temperature and is converted into liquid in a working state, gas is removed to reduce thermal resistance, phase change heat absorption is realized to realize rapid temperature equalization, and ultrahigh heat conduction efficiency is obtained.

Preferably, the liquid metal is selected from gallium, indium, tin, bismuth or alloys thereof, or doped mixtures thereof with other metals, oxides of other metals, non-metals or non-metal oxides; the other metal is selected from copper, aluminum, gold, silver, tungsten, rhodium or iridium, and the nonmetal is carbon or silicon.

Further preferably, the carbon includes, but is not limited to, diamond, graphene, or carbon nanotubes, etc.

The purpose of doping other substances in the liquid metal is to adjust the melting point of the liquid metal, so that the liquid metal can be solid at normal temperature and liquid at a working state. In order to match with heating devices with different operating temperatures, in practical application, the components and proportions of the elements in the doping mixture are arbitrary components and proportions which meet requirements.

The liquid metal is doped with other substances only for adjusting the melting point, and compared with the prior art which needs to add expensive auxiliary agents to improve the performance of the liquid metal, the liquid metal is lower in cost.

Preferably, the interstices of the second area of the array of micro mastoids are entirely filled with liquid metal. In order to furthest eliminate the air in the contact area of the reinforced heat dissipation plate and the heating device, the packaging liquid level of the liquid metal is equal to the height of the micrometer mastoid, namely, the gap is completely filled with the liquid metal, so that the flatness is ensured, and the error is not more than +/-0.5 mm.

Preferably, the material of the body of the strengthened heat dissipation plate includes, but is not limited to, copper or its alloy or its oxide, aluminum or its alloy or its oxide, iron or its alloy or its oxide, stainless steel, gold, silver, silicon or its oxide or its doped semiconductor, etc.

Preferably, the body of the reinforced heat dissipation plate comprises a completely filled mode and a partially filled mode. Wherein, the complete filling relates to conventional solid heat dissipation plates, such as fins, fin plates, heat sinks and the like; the partial filling relates to a heat dissipation plate based on the principle of a heat pipe (the residual space is filled with low-pressure refrigerant medium to form evaporation-condensation internal circulation), such as a heat pipe, a soaking plate, a cold plate and the like.

Preferably, the reinforced heat dissipation plate has a flat basic appearance and includes at least two functional surfaces, i.e., a top surface (upper surface) and a bottom surface (lower surface).

Preferably, the reinforced heat dissipation plate has additional external appearance meeting the actual requirement of the integrated circuit, including but not limited to a screw hole structure reserved for mounting a matching device, a fastening structure supplemented for improving mechanical strength, a fin structure added for improving the flow of a cooling medium, a groove or a ridge structure cut for avoiding other electronic components, and the like.

A preparation method of the self-sealing type super-gas-dredging immersion type phase change liquid cooling reinforced heat dissipation plate comprises the following steps: integral forming of the reinforced radiating plate, etching of the surface of the reinforced radiating plate to form a micrometer mastoid array, regulation and control of the infiltration property of the micrometer mastoid array and packaging of liquid metal in the second area.

Preferably, the integral forming method of the reinforced heat dissipation plate includes, but is not limited to, casting, forging, rolling, stamping, drawing, injection, welding, cutting, folding, slotting, nesting, grinding, powder metallurgy, 3D printing and the like.

Preferably, the etching method for forming the micrometer mastoid array by enhancing the surface etching of the heat dissipation plate is laser integrated etching. The laser integrated etching can simultaneously form the micrometer mastoid array and the nanometer folds on the surface of the micrometer mastoid. Specific implementation methods include laser moving path, laser filling process, laser photothermal action and laser repetitive processing, see the patent granted by the applicant (application publication No. CN 109974512 a).

One of the purposes of regulating and controlling the infiltration property of the micro mastoid array is to ensure that the surface of the first area of the reinforced heat dissipation plate obtains the property of super-open air (the adhesion force of bubbles under liquid is less than 20 mu N) aiming at a refrigerant medium so as to be beneficial to the quick separation of phase-change bubbles; another object is to obtain the properties of the second region that are superior to those of liquid metal (static contact angle less than 10 °) to facilitate stable encapsulation of the liquid metal. Preferably, the method for regulating the infiltration property of the micrometer mastoid array comprises chemical reagent modification, functional medium deposition, thermal modification, plasma treatment, ozone treatment or ultraviolet irradiation.

Further preferably, the functional medium deposition method includes, but is not limited to, chemical vapor deposition, physical vapor deposition, atomic layer deposition, or the like. The thermal modification is performed by a method such as calcination or annealing.

Preferably, the encapsulation of the liquid metal in the second region comprises the following steps: preheating the reinforced heat dissipation plate, then infiltrating and filling the molten liquid metal into the gaps of the micrometer mastoid array in the second area, and then cooling and solidifying to finish the packaging of the liquid metal.

Preferably, preheating the enhanced heat spreader plate to 20 ℃ and above the melting temperature of the liquid metal prevents the liquid metal from partially or completely solidifying and interfering with or retarding its wetting fill in the array gaps.

When the liquid metal is a metal simple substance or an alloy, the infiltration process can be directly carried out after the liquid metal is melted; if the liquid metal is a doped mixture, the metal simple substance or alloy needs to be heated and melted first, then other metal or nonmetal substances to be doped are supplemented, and meanwhile, the metal simple substance or alloy is fully and uniformly mixed by using methods such as physical grinding or mechanical stirring and the like for use.

Preferably, the liquid metal infiltration filling method includes, but is not limited to, natural infiltration filling, vacuum or pressure assisted infiltration filling, optical or electric or magnetic induced infiltration filling, and the like.

Preferably, the temperature of the reduced temperature solidification is at least 5 ℃ below the solidification temperature of the liquid metal, ensuring complete solidification of the liquid metal.

The self-sealing type super-gas-dredging immersion type phase change liquid cooling enhanced heat dissipation plate provided by the invention is synergistic with both 'contact thermal resistance reduction' and 'liquid-gas phase change promotion', and particularly supports high heating density (heat flow density 100W/cm)²Above) cooling and heat dissipation of electronic devices, including but not limited to meeting practical application requirements in fields such as data center servers, aerospace thermal control equipment, advanced power batteries, and the like.

The invention has the following beneficial effects:

the self-sealing type super-gas-dredging immersion type phase change liquid cooling strengthened cooling plate provided by the invention comprises a first area and a second area. Wherein the second region has lower thermal contact resistance with the heating device, faster heat transfer and temperature equalization, and the temperature equalization rate of liquid metal solid-liquid phase change is more than 1cm²S, and can automatically fill the gap between the contact surface of the heat sink and the heat generating device to obtain a material close to the main body of the enhanced heat sink (such as copper, with a thermal conductivity of about 400W m^-1K^-1) The ultra-high thermal conductivity. Meanwhile, the specific surface area of the micrometer mastoid array in the first area is larger, the vaporization cores are more, the adhesion retardation to phase-change bubbles is weaker, and the boiling transmission is enhancedThe thermal performance is better, and particularly, the high heat density (heat flow density of 100W/cm) is supported²The above) cooling and heat dissipation of the electronic device can reduce the initial overheating temperature of the refrigerant medium by 8-32 ℃ compared with the boiling point of the refrigerant medium, and the immersion type phase change liquid cooling performance is improved by more than 10 times compared with the surface of a conventional heat dissipation part and is improved by more than 1 time compared with the surface of commercial sintered copper particles.

In addition, compared with the existing product, the reinforced heat dissipation plate has the advantages of low cost, convenience in assembly and disassembly, stable performance, natural leakage prevention, simple, flexible and controllable preparation process, short period, high precision and easiness in batch production, and has good application prospects in the fields of data center servers, aerospace thermal control equipment, advanced power batteries and the like.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Fig. 1 is a schematic view illustrating a self-sealing type super-open-air immersion type phase-change liquid cooling strengthened heat dissipation plate in embodiment 1.

Fig. 2 shows an enlarged plan view and a sectional front view of a first region distributed on the upper surface (top surface) of the strengthened heat dissipation plate in example 1.

Fig. 3 is an enlarged bottom view and a sectional front view showing a first region and a second region distributed on the lower surface (bottom surface) of the reinforcing heat radiating plate in example 1.

Fig. 4 is a schematic product 3D view illustrating a self-sealing type super-hydrophobic immersion type phase-change liquid cooling strengthened heat dissipation plate meeting practical requirements of an integrated circuit in embodiment 1.

Wherein, 1-strengthen the cooling plate; 2-strengthening the upper surface (top surface) of the heat dissipation plate; 3-strengthening the lower surface (bottom surface) of the heat dissipation plate; 4-a first area distributed on the upper surface (top surface) of the reinforced heat dissipation plate; 5-a micro mastoid array within the first region; 6-a second area distributed on the lower surface (bottom surface) of the reinforced heat dissipation plate; 7-a first area distributed on the lower surface (bottom surface) of the reinforced heat dissipation plate; 8-isolation zones; 9-the mastoid process in the first zone; 10-nano-folds of the micro-mastoid surface in the first region; 11-micrometer mastoid array gaps in the first region; 12-liquid metal in the second region; 13-plate; 14-prismatic table (add-on appearance); 15-fastening tape (additional appearance); 16-screw holes (additional appearance); 17-the micrometer mastoid in the second zone.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. Similar parts in the figures are denoted by the same reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.

Example 1

A self-close-connection type super-gas-dredging immersion type phase-change liquid cooling enhanced cooling plate comprises a first area and a second area, wherein the surface of the enhanced cooling plate is provided with a first surface and a second surface; the surface of the enhanced radiating plate in the first area is distributed with a micrometer mastoid array, the surface of the enhanced radiating plate in the second area is distributed with a micrometer mastoid array, and liquid metal is sealed in gaps of the micrometer mastoid array; the contact area of the reinforced heat dissipation plate and the heating device comprises a second area. The large-area micro-nano composite super-gas-dredging enhanced boiling structure in the first area can fill a gap between a heating device and liquid metal in the second area, and has high heat conduction efficiency. As shown in fig. 1 to 3, the specific scheme is as follows:

the reinforced heat sink 1 is formed by casting and made of copper (thermal conductivity about 400W m)^-1K^-1) The material is completely filled, the basic appearance is a standard flat plate with the size of 100mm multiplied by 60mm multiplied by 3mm, and no additional appearance exists. After primary surface grinding and polishing, integrally etching the upper surface (top surface) 2 by using laser to form a first area 4, and forming a first area 7 and a second area 6 on the lower surface (bottom surface) 3; the second region 6 encapsulating the liquid metal has an area of 38mm × 38mm, and is in contact with a chip having an area of 40mm × 40mm, and an isolation strip 8 is present between the second region 6 and the first region 7. The surface of the micro-mastoid 9 of the first region 4 and 7 has nano-folds 10, the height of the micro-mastoid 9 in the first region is 60 μm, the equivalent diameter is about 50 μm, the thickness of the nano-folds 10 of the surface is about 500nm, and the width of the micro-mastoid array gap 11 in the first region is about 50 μm. The size of the micro-mastoid 17 in the second region 6 coincides with the size of the micro-mastoid 9 in the first region.

By 1.0mol L^-1Sodium hydroxide and 0.5mol L^-1The sodium persulfate solution chemically modifies the first area 4 distributed on the upper surface (top surface) of the reinforced heat dissipation plate and the first area 7 distributed on the lower surface (bottom surface) of the reinforced heat dissipation plate to obtain super-hydrophobic property, and the adhesion force of bubbles under liquid is less than 10 mu N. By 1.0mol L^-1And (3) modifying the 6-micron mastoid array in the second area by hydrochloric acid to obtain the property of the super-hydrophilic liquid metal, heating at the constant temperature of 60 ℃ to naturally infiltrate and fill the liquid metal 12 gallium simple substance (the melting point is about 30 ℃), completing the uniform packaging of the 3-micron mastoid array gap on the bottom surface, and then refrigerating at 0 ℃ for cooling and curing for 2h to obtain the liquid metal 12 in the second area 6.

In the embodiment, the enhanced heat dissipation plate has low contact thermal resistance and high heat transfer temperature uniformity, the temperature of the area of 100mm multiplied by 60mm on the upper surface can be uniformly distributed within 50s at 60 ℃, and the measured total thermal conductivity is up to 395.4W m^-1K^-1。

The reinforced heat dissipation plate in the embodiment has the advantages of large specific surface area, more vaporization cores, weak adhesion retardation to phase change bubbles and excellent reinforced boiling effect, and can reduce the initial overheating temperature of bulk water boiling by 32 ℃, reduce the initial overheating temperature of electronic fluoridizing liquid boiling by 8 ℃ and improve the reinforced boiling heat transfer performance by 10 times compared with the conventional copper heat dissipation surface.

In the embodiment, the main body of the reinforced heat dissipation plate is made of the most common red copper, the liquid metal is the simplest elemental gallium, and only an ultrathin layer with the thickness of 20 mu m needs to be formed, so that the advantages of economical materials, low cost and the like are fully embodied; meanwhile, the preparation processes of casting molding, surface grinding and polishing, laser etching, chemical modification and the like are simple and controllable, and large-scale production is easy to realize.

Example 2

The utility model provides a satisfy integrated circuit actual need from close type of connecing surpass gas-dredging submergence formula phase transition liquid cooling strengthening heating panel product, the concrete scheme is as follows:

a solid red copper reinforced heat dissipation plate formed by cutting, pressing, grinding and polishing is shown in FIG. 4, and has a basic appearance of a flat plate 13 with dimensions of 120mm × 78mm × 2mm, additional appearances including a prism 14 with a bottom surface centered at 40mm × 40mm × 8mm, a fastening band 15 with a side wing centered at 55mm × 9mm × 8mm, and specific positionsA screw hole 16 with the diameter of 7mm is reserved. Integrally etching the micrometer mastoid arrays by using laser, wherein the micrometer mastoid arrays are distributed on the upper surface and the lower surface of the flat plate 13, the periphery and the bottom surface of the frustum pyramid 14 and the upper surface, the lower surface and the side surfaces of the fastening belt 15; wherein the area of the second region of the bottom surface of the frustum ridge 14 is 38mm × 38mm, and the chip with the area of 40mm × 40mm is in contact with the second region of the bottom surface of the frustum ridge 14, the height of the micrometer mastoid in the second region of the bottom surface of the frustum ridge 14 is 20 μm, and the height of the micrometer mastoid in the first region of the surface of the frustum ridge 14 is 40 μm. The height of the micrometer mastoid in the first region on the other surface of the reinforced heat dissipation plate is 60 μm. In addition, other structural parameters of the micro-mastoid are consistent, including the equivalent diameter of the cone-shaped micro-mastoid being about 30 μm, the thickness of the nano-folds on the surface of the micro-mastoid being about 50nm, and the distance between adjacent micro-mastoids being 30 μm. The super-hydrophobic property is obtained by 200W plasma treatment with 1.0mol L^-1The method comprises the steps of chemically modifying the bottom surface of a 38mm X38 mm prismatic table by a sodium hydroxide solution to obtain the ultra-hydrophilic liquid metal property, heating at a constant temperature of 80 ℃ to enable liquid metal indium tin bismuth alloy (50% of indium, 20% of tin, 30% of bismuth and about 60 ℃ of melting point) to be induced and soaked and filled into a micrometer mastoid array on the bottom surface of the prismatic table, uniformly packaging, and naturally cooling and curing for 12 hours.

The reinforced heat dissipation plate product in the embodiment can be butted with a real data center server, the prismatic table can effectively avoid other electronic elements on the mainboard, and the fastening belt and the screw hole are convenient for tightly loading the reinforced heat dissipation plate contacted with the chip; the super-large area (almost covering all functional surfaces) enhanced boiling structure can remarkably promote the liquid-gas phase change behavior of the refrigerant medium and improve the liquid cooling performance of the immersed phase change. The micro immersion type phase-change liquid cooling test shows that the reinforced heat dissipation plate of the embodiment enables 300-420W/cm²The working temperature of the high-heating-density electronic device is 68-74 ℃, and the immersion type phase change liquid cooling performance is improved by more than 1 time compared with the surface of commercial sintered copper particles.

Example 3

The basic appearance, the size parameters and the subsequent preparation method of the self-close connection type super-hydrophobic immersed phase-change liquid cooling strengthened heat dissipation plate product are consistent with those of the embodiment 2 except that the heat pipe type red copper vapor chamber is formed by using the processes of 3D printing, injection, welding and the like in the forming stage.

Comparative example 1

The reinforced heat dissipation plate in the comparative example 1 is completely the same as the example 3, except that the liquid metal is encapsulated in the gaps of the micro mastoid array in the second region in the example 3, while the liquid metal is not encapsulated in the reinforced heat dissipation plate in the comparative example, and a commercial indium metal heat sink is used to fill the contact surface.

In the embodiment 3, the heat dissipation plate product is repeatedly assembled and disassembled in the micro immersion type phase change liquid cooling device and tested for 60 times, no liquid metal side leakage is found, and the micro immersion type phase change liquid cooling test shows that the liquid metal side leakage is 180-320W/cm²The working temperature of the high-heating-density electronic device is 58-62 ℃, and 300W/cm²The fluctuation error of the working temperature of the heat-generating density electronic device is +/-2.6 ℃, and the comparative example 1 of filling the contact surface with the commercial metal indium radiating fin is complex in loading and unloading process, namely 180-320W/cm²The working temperature of the high-heating-density electronic device is 58-72 ℃, and 300W/cm²The fluctuation error of the working temperature of the electronic device reaches up to +/-12.4 ℃, which fully embodies the advantages of convenient assembly and disassembly, stable performance, natural leakage prevention and the like.

It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations or modifications may be made on the basis of the above description, and all embodiments may not be exhaustive, and all obvious variations or modifications belonging to the technical solutions of the present invention are within the scope of the present invention.