CN110267493B - Flexible ultrathin liquid absorption core with hierarchical porous structure and manufacturing method thereof - Google Patents
Flexible ultrathin liquid absorption core with hierarchical porous structure and manufacturing method thereof Download PDFInfo
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- CN110267493B CN110267493B CN201910506732.0A CN201910506732A CN110267493B CN 110267493 B CN110267493 B CN 110267493B CN 201910506732 A CN201910506732 A CN 201910506732A CN 110267493 B CN110267493 B CN 110267493B
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- 239000007788 liquid Substances 0.000 title claims abstract description 27
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 16
- 238000010521 absorption reaction Methods 0.000 title claims abstract description 14
- 239000011148 porous material Substances 0.000 claims abstract description 38
- 239000013354 porous framework Substances 0.000 claims abstract description 25
- 238000000034 method Methods 0.000 claims abstract description 16
- 239000002086 nanomaterial Substances 0.000 claims abstract description 15
- 239000002184 metal Substances 0.000 claims description 13
- 229910052751 metal Inorganic materials 0.000 claims description 13
- 230000008569 process Effects 0.000 claims description 12
- 238000005245 sintering Methods 0.000 claims description 12
- 239000000835 fiber Substances 0.000 claims description 7
- 238000004070 electrodeposition Methods 0.000 claims description 6
- 230000009467 reduction Effects 0.000 claims description 4
- 238000005229 chemical vapour deposition Methods 0.000 claims description 2
- 238000005260 corrosion Methods 0.000 claims description 2
- 230000007797 corrosion Effects 0.000 claims description 2
- 238000003672 processing method Methods 0.000 claims description 2
- 239000007790 solid phase Substances 0.000 claims description 2
- 238000005507 spraying Methods 0.000 claims description 2
- 238000004544 sputter deposition Methods 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims description 2
- 230000002745 absorbent Effects 0.000 claims 2
- 239000002250 absorbent Substances 0.000 claims 2
- 230000017525 heat dissipation Effects 0.000 abstract description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 9
- 229910052802 copper Inorganic materials 0.000 description 5
- 239000010949 copper Substances 0.000 description 5
- 239000011159 matrix material Substances 0.000 description 4
- 238000004377 microelectronic Methods 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 239000002114 nanocomposite Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical group [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 239000005751 Copper oxide Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910000431 copper oxide Inorganic materials 0.000 description 1
- 229910000365 copper sulfate Inorganic materials 0.000 description 1
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002070 nanowire Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K7/00—Constructional details common to different types of electric apparatus
- H05K7/20—Modifications to facilitate cooling, ventilating, or heating
- H05K7/2029—Modifications to facilitate cooling, ventilating, or heating using a liquid coolant with phase change in electronic enclosures
- H05K7/20336—Heat pipes, e.g. wicks or capillary pumps
Abstract
The invention relates to a flexible ultrathin liquid absorption core with a hierarchical porous structure, which comprises a primary porous framework structure and a secondary micro-nano porous structure; the primary porous framework structure is a flexible layer, primary pores are uniformly distributed, and the thickness of the primary porous framework structure and the size of the primary pores are millimeter-sized; the secondary micro-nano porous structure is uniformly distributed with secondary pores, the thickness of the secondary micro-nano porous structure is nano-scale, the size of the secondary pores is micro-scale, or the size of part of the secondary pores is micro-scale, and the size of part of the secondary pores is nano-scale; the secondary micro-nano porous structure is attached to the surface of the primary porous framework structure; the three-stage nano-structure is attached to the surfaces of the primary porous framework structure and the secondary micro-nano porous structure. And also relates to a method for manufacturing the flexible ultrathin liquid absorption core with the hierarchical porous structure. The invention can simultaneously meet the heat dissipation requirements of ultra-thin, flexible, strong capillary performance and the like, and belongs to the technical field of ultra-thin heat pipes.
Description
Technical Field
The invention relates to the technical field of ultrathin heat pipes, in particular to a flexible ultrathin liquid suction core with a hierarchical porous structure and a manufacturing method thereof.
Background
In recent years, with the rapid development of smart phones, smart watches and other microelectronic devices, the heating power of the smart phones, the effective heat dissipation volume of the smart phones, the smart watches and other microelectronic devices is gradually increased, and the heat dissipation problem of electronic chips is gradually increased. The ultrathin heat pipe has extremely high heat conductivity and extremely thin thickness, and is an ideal scheme for solving the difficult heat dissipation problem of the microelectronic device. The wick, which is the core component of the ultra-thin heat pipe, determines the heat transfer performance of the ultra-thin heat pipe. Most of the wicks of the existing ultrathin heat pipes adopt a micro-groove structure or a silk screen structure, so that the capillary performance is poor, and the ever-increasing heat dissipation requirement is difficult to meet. In addition, the development of microelectronic devices in flexibility requires that the heat sink device also have better flexibility.
No liquid absorbing core with good flexibility and good capillary property exists in the prior art.
Disclosure of Invention
Aiming at the technical problems existing in the prior art, the invention aims at: the flexible ultrathin liquid suction core with the hierarchical porous structure has good flexibility and good capillary performance, and the manufacturing method of the flexible ultrathin liquid suction core with the hierarchical porous structure is provided.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a flexible ultrathin liquid absorption core with a hierarchical porous structure comprises a primary porous framework structure and a secondary micro-nano porous structure; the primary porous framework structure is a flexible layer, primary pores are uniformly distributed, and the thickness of the primary porous framework structure and the size of the primary pores are millimeter-sized; the secondary micro-nano porous structure is uniformly distributed with secondary pores, the thickness of the secondary micro-nano porous structure is nano-scale, the size of the secondary pores is micro-scale, or the size of part of the secondary pores is micro-scale, and the size of part of the secondary pores is nano-scale; the secondary micro-nano porous structure is attached to the surface of the primary porous framework structure. The surface as referred to herein includes surfaces within the primary pores and surfaces outside the primary pores of the primary porous skeleton structure.
As a preference, a flexible ultrathin wick with a hierarchical porous structure, further comprising a tertiary nanostructure; three-level pores are uniformly distributed in the three-level nano structure, and the size of the three-level pores is nano-level; the three-level nano structure is attached to the surfaces of the first-level porous framework structure and the second-level micro-nano porous structure. The surface as referred to herein includes a surface inside primary pores and a surface outside primary pores of the primary porous skeleton structure, and a surface inside secondary pores and a surface outside secondary pores of the secondary micro-nano porous structure.
Preferably, the primary porous framework structure is a net and is a wire mesh or a metal fiber sintered felt.
Preferably, the secondary micro-nano porous structure is attached only to the inner surface of the primary pores.
Preferably, the primary porous skeleton structure is a crisscross network structure.
Preferably, the flexible ultrathin wick has a hierarchical porous structure, and further comprises grooves extending longitudinally or transversely through the wick.
Preferably, the diameter of the metal wires or metal fibers is 0.2-0.5mm, and the distance between two adjacent parallel metal wires or metal fibers is 1-3mm; the distance between two ends of the groove and the edge of the primary porous framework structure is 5-10mm; the thickness of the primary porous skeleton structure is 0.05-0.15mm.
A method of making a flexible ultrathin wick having a hierarchical porous structure, comprising: the method comprises the following steps: a. manufacturing a net-shaped primary porous framework structure; b. the secondary micro-nano porous structure is attached to the inner surface of a primary pore of the primary porous skeleton structure through electrochemical deposition, solid-phase sintering or physical sputtering process, and the primary porous skeleton structure and the secondary micro-nano porous structure are fixed together through the sintering process; c. after adopting physical spraying, chemical corrosion or chemical vapor deposition process, the three-level nano structure is manufactured by a sintering process, and the three-level nano structure is attached to the surfaces of the first-level porous skeleton structure and the second-level micro-nano porous structure during manufacturing.
Preferably, after step c, the grooves are formed by removing the wick structure by laser machining.
Preferably, the sintering process of the step b and the step c is finished in steps or is finished by combining in the step c once; and c, performing reduction treatment.
The principle of the invention is as follows: the primary porous skeleton structure is adopted as a matrix, so that the composite material has good flexibility and mechanical properties; the capillary performance and the mechanical performance of the matrix are enhanced by adopting a secondary micro-nano porous structure and a tertiary nano structure. Through compound wire mesh skeleton and micro-nano porous structure, can reach heat dissipation demands such as ultra-thin, flexibility and capillary performance are strong simultaneously.
The invention has the following advantages:
(1) By growing the micro-nano porous structure in the primary porous skeleton structure matrix, the capillary performance of the metal wire mesh and the metal fiber sintered felt is enhanced, the flexibility and the thickness of the porous matrix can be kept unchanged basically, and the micro-nano porous structure is a good choice of the liquid absorption core of the flexible ultrathin heat dissipation device.
(2) The core of the invention is that a micro-nano composite structure with smaller scale grows on a primary porous skeleton structure substrate, and different micro-nano composite structures and liquid absorption core stages can be selected according to different substrate materials and actual application requirements, so that the invention has good applicability.
(3) The invention has simple manufacturing process and low cost, has better flexibility and capillary property, and can meet the use requirements of ultrathin and flexible heat dissipation devices.
(4) The secondary micro-nano porous structure is only attached to the inner surface of the primary pore, and the thickness of the primary porous skeleton structure can not be increased.
(5) By adopting the groove structure, the permeability of liquid working medium reflux can be increased, and the performance of the liquid suction core is improved.
Drawings
Fig. 1 is a schematic structural view of a flexible ultrathin wick with a hierarchical porous structure according to the first embodiment.
Fig. 2 is a schematic structural view of a flexible ultrathin wick with a hierarchical porous structure according to the second embodiment.
Fig. 3 is a schematic structural view of a flexible ultrathin wick with a hierarchical porous structure according to embodiment three.
Wherein 1 is a primary porous skeleton structure, 2 is a secondary micro-nano porous structure, 3 is a tertiary nano structure, 4 is a groove, 11 is a primary pore, and 21 is a secondary pore.
Detailed Description
The present invention will be described in further detail with reference to the following embodiments.
Example 1
A flexible ultrathin liquid absorption core with a hierarchical porous structure comprises a primary porous framework structure, a secondary micro-nano porous structure and a tertiary nano structure.
The primary porous skeleton structure is a 300-mesh copper wire mesh structure and comprises copper wires and primary pores formed between the copper wires. The diameter of the copper wire is 0.05mm, and the overall thickness of the copper wire mesh is about 0.08mm.
The secondary micro-nano porous structure is attached to the inner surface of the primary pore by a constant current electrodeposition method and comprises micro-nano scale copper particles and irregular secondary pores formed by adjacent copper particles. The constant current electrodeposition method of the embodiment adopts a two-electrode system, a copper wire mesh is used as a cathode, another copper sheet is used as an anode, the distance between the two electrodes is 10mm, the electrolyte adopts 0.4M copper sulfate and 1.5M sulfuric acid, and the current density is 1A/cm 2 The electrodeposition time was 40s.
After the electro-deposition is finished, cleaning a sample, then placing the sample into a muffle furnace for sintering process treatment, wherein the sintering temperature is 350 ℃, and preserving the heat in an air environment for 1 hour; the sintering process not only can form firm sintering diameter between the primary porous framework structure and the secondary micro-nano porous structure, but also can form a tertiary nano structure (tertiary copper oxide nanowire structure) on the surfaces of the primary porous framework structure and the secondary micro-nano porous structure; and finally, carrying out reduction treatment on the liquid suction core, adopting hydrogen atmosphere for reduction, heating the liquid suction core to 300 ℃ in the hydrogen atmosphere, preserving heat for 1 hour, and cooling along with a furnace to obtain the final flexible ultrathin liquid suction core with the three-level porous structure.
Example two
The present embodiment adds a trench structure on the basis of the first embodiment.
Removing the wick structure with the width of 0.3mm on the surface of the wick by a laser processing method to form mutually parallel transverse grooves, wherein the distance between the mutually parallel grooves is 1.5mm; the grooves can increase the permeability of liquid working medium backflow and improve the performance of the liquid suction core.
This embodiment is not mentioned in part as embodiment one.
Example III
The embodiment provides a flexible ultrathin liquid absorption core with a hierarchical porous structure, which comprises a primary porous framework structure and a secondary micro-nano porous structure.
The first-stage porous skeleton structure and the second-stage micro-nano porous structure are the same as in the first embodiment.
The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principle of the present invention should be made in the equivalent manner, and the embodiments are included in the protection scope of the present invention.
Claims (3)
1. A method of making a flexible ultrathin wick having a hierarchical porous structure, comprising: the flexible ultrathin liquid absorption core comprises a primary porous framework structure and a secondary micro-nano porous structure; the primary porous framework structure is a flexible layer, primary pores are uniformly distributed, and the thickness of the primary porous framework structure and the size of the primary pores are millimeter-sized; the secondary micro-nano porous structure is uniformly distributed with secondary pores, the thickness of the secondary micro-nano porous structure is nano-scale, the size of the secondary pores is micro-scale, or the size of part of the secondary pores is micro-scale, and the size of part of the secondary pores is nano-scale; the secondary micro-nano porous structure is attached to the surface of the primary porous framework structure;
the flexible ultrathin liquid absorption core also comprises a three-level nano structure; three-level pores are uniformly distributed in the three-level nano structure, and the size of the three-level pores is nano-level; the three-level nano structure is attached to the surfaces of the first-level porous framework structure and the second-level micro-nano porous structure;
the primary porous framework structure is a crisscross net structure and is a metal wire mesh or a metal fiber sintered felt;
the secondary micro-nano porous structure is only attached to the inner surface of the primary pore;
the flexible ultrathin liquid absorption core further comprises a groove which extends longitudinally or transversely and penetrates through the liquid absorption core;
a method of making a flexible ultrathin wick comprising the steps of:
a. manufacturing a net-shaped primary porous framework structure;
b. the secondary micro-nano porous structure is attached to the inner surface of a primary pore of the primary porous skeleton structure through electrochemical deposition, solid-phase sintering or physical sputtering process, and the primary porous skeleton structure and the secondary micro-nano porous structure are fixed together through the sintering process;
c. after adopting physical spraying, chemical corrosion or chemical vapor deposition process, manufacturing a three-level nano structure through a sintering process, attaching the three-level nano structure to the surfaces of the first-level porous skeleton structure and the second-level micro-nano porous structure during manufacturing, and removing the liquid absorption core structure through a laser processing method to form a groove after the step c.
2. A method of making a flexible ultrathin liquid absorbent core having a hierarchical porous structure according to claim 1 wherein: the diameter of the metal wires or the metal fibers is 0.2-0.5mm, and the distance between two adjacent parallel metal wires or metal fibers is 1-3mm; the distance between two ends of the groove and the edge of the primary porous framework structure is 5-10mm; the thickness of the primary porous skeleton structure is 0.05-0.15mm.
3. A method of making a flexible ultrathin liquid absorbent core having a hierarchical porous structure according to claim 1 wherein: the sintering process of the step b and the step c is finished in steps or is finished by combining in the step c once; and c, performing reduction treatment.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110769645B (en) * | 2019-10-11 | 2020-08-21 | 大连理工大学 | Ultrathin flat plate heat pipe liquid absorption core and manufacturing method thereof |
| CN111933592B (en) * | 2020-08-14 | 2022-07-19 | 西安交通大学深圳研究院 | Electronic device heat dissipation structure with three-dimensional net structure and manufacturing method |
| CN115625484B (en) * | 2022-10-14 | 2023-09-01 | 广东畅能达科技发展有限公司 | Bending special-shaped ultrathin soaking plate and manufacturing process and application thereof |
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| WO2004099068A2 (en) * | 2003-05-05 | 2004-11-18 | Nanosys, Inc. | Nanofiber surfaces for use in enhanced surface area applications |
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|---|---|---|---|---|
| WO2004099068A2 (en) * | 2003-05-05 | 2004-11-18 | Nanosys, Inc. | Nanofiber surfaces for use in enhanced surface area applications |
| CN101410685A (en) * | 2006-03-03 | 2009-04-15 | 伊路米耐克斯公司 | Heat pipe with nanotstructured wicking material |
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