Search

CN-121986001-A - Method for manufacturing porous capillary structure

CN121986001ACN 121986001 ACN121986001 ACN 121986001ACN-121986001-A

Abstract

The present invention relates to a method (100) of manufacturing a porous capillary structure (310) having one or more micro-channels (312) using a mold core (202). The method (100) includes inserting (102) the mold core (202) into a mold (204) and filling (104) the mold (204) with a metal powder (206). The method (100) further includes sintering (106) the metal powder (206) in the mold (204) to form a porous capillary structure (310) including the mold core (202), and dissolving (108) the mold core (202) to form one or more micro-channels (312) within the porous capillary structure (310). Furthermore, the invention relates to a loop heat pipe (300) comprising a porous capillary structure (310) manufactured according to the method (310).

Inventors

  • NIU JUNCHAO
  • FREDERICK OLSEN
  • Dimit Kush
  • Pavel Mahnachi
  • TIAN DENGFENG
  • HUANG YIYUAN

Assignees

  • 华为技术有限公司

Dates

Publication Date
20260505
Application Date
20231017

Claims (20)

  1. 1. A method (100) for manufacturing a porous capillary structure (310), the method (100) comprising: inserting (102) a mold core (202) into a mold (204); filling (104) the mold (204) with a metal powder (206); Sintering (106) the metal powder (206) in the mold (204) to form a porous capillary structure (310) comprising the mold core (202); -dissolving (108) the mould core (202) to form one or more micro-channels (312) within the porous capillary structure (310).
  2. 2. The method (100) of claim 1, wherein the shape of the one or more microchannels (312) corresponds to the shape of the mold core (202).
  3. 3. The method (100) according to claim 1 or 2, wherein the one or more micro-channels (312) are vias and/or through holes within the porous capillary structure (310).
  4. 4. The method (100) of any of the preceding claims, wherein the one or more microchannels (312) are interconnected to one another.
  5. 5. The method (100) of any of the preceding claims, wherein the one or more micro-channels (312) extend parallel to each other within the porous capillary structure (310).
  6. 6. The method (100) according to any one of the preceding claims, wherein the one or more micro-channels (312) are arranged equidistant from each other within the porous capillary structure (310).
  7. 7. The method (100) of any one of claims 1 to 6, wherein the one or more micro-channels (312) extend along a straight line within the porous capillary structure (310).
  8. 8. The method (100) of any one of claims 1 to 6, wherein the one or more microchannels (312) extend in a meandering manner within the porous capillary structure (310).
  9. 9. The method (100) of any of the preceding claims, wherein the one or more microchannels (312) have the same diameter.
  10. 10. The method (100) of any one of claims 1 to 9, wherein the one or more microchannels (312) have a constant diameter.
  11. 11. The method (100) of any one of claims 1 to 9, wherein the one or more microchannels (312) have varying diameters.
  12. 12. The method (100) of claim 11, wherein the diameter is at least partially tapered.
  13. 13. The method (100) of any of the preceding claims, wherein the porous capillary structure (310) comprises an input port (314) and an output port (316) connected to the one or more microchannels (312).
  14. 14. The method (100) according to any one of the preceding claims, wherein the mould core (202) is dissolved using a solvent.
  15. 15. The method (100) of claim 14, wherein the solvent is any one of water, ethanol, ethylene glycol, and acetone.
  16. 16. The method (100) according to any one of the preceding claims, wherein the mould core (202) is a preformed mould core.
  17. 17. The method (100) of any of the preceding claims, wherein the mold core (202) has a melting temperature above 700 ℃.
  18. 18. The method (100) of claim 17, wherein the mold core (202) is made of a soluble inorganic salt.
  19. 19. The method (100) of claim 18, wherein the soluble inorganic salt is sodium chloride crystals or sodium fluoride crystals.
  20. 20. The method (100) of any of the preceding claims, wherein the metal powder (206) is a single metal or alloy metal powder.

Description

Method for manufacturing porous capillary structure Technical Field Embodiments of the present invention relate to a method of manufacturing a porous wick structure and a loop heat pipe including the porous wick structure manufactured according to the method. Background With the continuous improvement of the integration level of electronic chips and power devices, the heat flux density is continuously increased. Especially in the field of telecommunications, the power consumption of digital processing units has become one of the important factors affecting the evolution of base stations. The traditional passive natural air cooling mode can not meet the challenges faced in the heat dissipation field of the communication industry, so that the two-phase heat dissipation technology is widely applied. The two-phase heat dissipation technology can realize high heat transfer efficiency without active devices such as fans. Loop Heat Pipe (LHP) is a two-phase heat dissipation technology that has been the focus of research due to its unique antigravity heat transfer advantage. LHP technology utilizes a refrigerant to exchange heat in a liquid-phase and vapor-phase conversion process, which refrigerant achieves mass transfer in the antigravity direction by means of a porous capillary structure, thereby completing the cycle of evaporation and condensation. Disclosure of Invention It is an aim of embodiments of the present invention to provide a solution that alleviates or solves the disadvantages and problems of the conventional solutions. It is a further object of embodiments of the invention to provide a simple method of manufacturing porous capillary structures with different microchannel geometries. The above and other objects are achieved by the subject matter of the independent claims. Further embodiments of the invention are provided in the dependent claims. According to a first aspect of the present invention, the above and other objects are achieved by a method for manufacturing a porous capillary structure, the method comprising: inserting a mold core into a mold; Filling the mold with a metal powder; Sintering the metal powder in the mold to form a porous capillary structure comprising the mold core; The mold core is dissolved to form one or more micro-channels within the porous capillary structure. An advantage of the method according to the first aspect is that a porous capillary structure with internal micro-channels can be manufactured in a simple manner. The method enables small-sized and complex-shaped internal micro-channels that cannot be fabricated by conventional processes to be formed in the porous capillary structure. The mould core can be removed by a simple dissolution process and the porous capillary structure is free from the risk of stress and deformation. Thus, the accuracy of the microchannel dimensions is high. In addition, the open porous structure and capillary properties of the inner surface of the microchannel may be maintained. In an implementation of the method according to the first aspect, the shape of the one or more micro-channels corresponds to the shape of the mould core. The advantage of this implementation is that the microchannels can be flexibly designed in a simple manner. Since the shape of the mold core can be diversified, the geometry of the corresponding micro-channel can be also diversified, and thus, a novel internal micro-channel and heat dissipation design can be provided. In one implementation of the method according to the first aspect, the one or more micro-channels are vias and/or through holes within the porous capillary structure. The advantage of this implementation is that the vapor escape channel and the liquid return channel can be integrated directly into a single porous capillary structure by a single sintering process, thus improving the fluid flow rate and/or reducing the pressure drop in the porous capillary structure. The integrated microchannels of the present invention may provide improved heat transfer efficiency and/or evaporation efficiency compared to the absence of microchannels or conventional microchannel shapes/forms. In one implementation of the method according to the first aspect, the one or more micro-channels are interconnected with each other. The advantage of this implementation is that heat leak losses can be minimized and mass transfer efficiency can be maximized, thereby greatly improving heat dissipation cycle efficiency. In one implementation of the method according to the first aspect, the one or more micro-channels extend parallel to each other within the porous capillary structure. An advantage of this implementation is that parallel microchannels may be positioned close to the heat source substrate, thereby reducing the mass transfer resistance of the refrigerant return liquid passing through the microchannels, increasing the contact surface with the porous capillary structure. In one implementation of the method according