TWI493150B - Heat pipe and method for forming the same - Google Patents

Description

Heat pipe and processing method thereof

The invention is a heat transfer technology, in particular to a heat pipe and a processing method thereof.

With the evolution of integrated circuit packaging technology and process, the internal circuit density is increased and miniaturized, which makes the speed and frequency of electronic components operate rapidly. However, when miniaturized electronic components operate at high speed, components are derived. A significant increase in heat generation per unit area results in a problem where the heat source is more concentrated on the wafer. The statistical results show that the proportion of all electronic products damaged due to overheating is as high as 55%, and it has been pointed out that every time the temperature is lowered by about 10 °C, the efficiency of the operation chip is increased by 1-3%, so the electronic components need an effective heat dissipation during operation. Designed to solve the problem of excessive concentration of heat sources, electronic equipment can maintain its reliability, stability and service life under long-term use.

Heat pipe products (such as heat pipes or temperature equalizing plates) have the characteristics of rapidly transferring heat generated by heat sources to the heat dissipating end, and thus are widely used in high heat concentration of electronic components, light emitting diodes (LEDs), solar panels, and the like. On components that require fast heat dissipation. The inside of the heat pipe is a low-pressure sealed space with a capillary structure and a filled working fluid. The internal low-pressure state causes the gas-liquid phase change temperature of the working fluid to be greatly reduced. At the time of operation, the evaporation zone encounters a heat-producing liquid phase change zone. A large amount of heat is taken, and the working fluid after gasification flows to the condensation zone due to the high pressure, and the liquid phase changes and condenses in the condensation zone, and the capillary structure is responsible for returning the condensed working fluid to the heating end, so that heating The end continues to have a working fluid, maintaining a closed loop soaking system with one end of evaporation and one end of condensation.

There are different heat transfer restrictions on the use of heat pipes. The copper-water heat pipes used in general heat dissipation are often limited to the capillary limit when applied. As the heat transfer rate increases, the mass flow rate of the working fluid increases. The force will bring the working fluid back to the maximum amount of the evaporation zone, which will result in the phenomenon that the evaporation zone has no working fluid drying and the heat pipe operation fails, and reaches the limit of the maximum heat transfer capacity of the heat pipe.

The present disclosure proposes a heat pipe and a processing method thereof, which use a chemical reaction to change the surface characteristics of the capillary structure of the existing heat pipe or the heat equalizing plate, so that the working fluid in the heat pipe and the modified capillary structure of the inner wall of the heat pipe have Different wettability promotes the capillary pressure difference of the driving working fluid flow provided by the capillary structure in the tube, thereby greatly increasing the maximum heat transfer amount of the heat pipe.

In one embodiment, the present disclosure provides a heat pipe processing method comprising the steps of: providing a metal pipe body having an opening at both ends, the metal pipe inner wall having a capillary structure surface; and oxidizing the capillary structure surface To form an oxidized structure surface.

In another embodiment, the present disclosure provides a heat pipe comprising: a metal pipe body having a first region in a pipe wall; a working fluid filled in the metal pipe; and a first oxidation The structure is formed on the inner tube wall of the first region, and the working fluid has a first contact angle on the first oxidized structure.

In order to enable the reviewing committee to have a further understanding and understanding of the features, objects and functions of the present invention, the related detailed structure of the device of the present invention and the concept of the design are explained in the following, so that the reviewing committee can understand the present invention. The detailed description is as follows: Please refer to FIG. 1 , which is a schematic flow chart of the first embodiment of the heat pipe processing method. In this embodiment, the method 2 includes the step 20 of providing a metal tube having an opening at both ends. As shown in Fig. 2, the figure is a side cross-sectional side view of the metal pipe body of the present disclosure. The metal pipe body 80 is a tubular body having a length of a columnar hollow, and the inner wall has a capillary structure surface 81. In this embodiment, the capillary structure surface 81 is formed by forming a groove structure in the tube wall of the metal tube. In another embodiment, a mesh structure may be formed on the inner tube wall or a porous metal structure may be sintered, and the pores of the mesh or sintered metal may be utilized as the capillary structure. The manner in which the capillary structure surface 81 is formed is well known to those skilled in the art and is therefore not limited by the foregoing aspects of the capillary structure surface 81. The metal pipe body 80 can be made of a material having good thermal conductivity, such as copper or aluminum. In the present embodiment, the metal pipe body 80 is a copper pipe. It should be noted that the cross-sectional shape of the metal pipe body 80 of the present invention may be circular, but not limited thereto.

Returning to Figure 1, then proceeding to step 21, oxidizing the surface of the capillary structure to form an oxidized structure surface having a first contact with a working fluid (e.g., water, but not limited thereto) angle. Please refer to FIGS. 3A to 3C, which are schematic diagrams of contact angles. The so-called contact angle is defined as the angle between the surface of the working fluid and the metal surface. In Figs. 3A to 3C, the contact angle relationship between the working fluid 91 and the different metal surfaces 90a, 90b, and 90c is shown, where θ 1 < θ 2 < θ 3 , and the smaller the contact angle, the hydrophilicity of the metal surface. The surface has a higher wettability, and the larger the contact angle, the more hydrophobic the metal surface, and the wettability is worse than the metal surface with a small contact angle.

Returning to Fig. 1, the manner of oxidation in step 21 can be carried out in a variety of ways. In one embodiment, the metal tube body having the capillary structure is unsealed at both ends, as shown in Fig. 4A. As shown, the metal pipe body 80 is immersed in the mixed reaction solution 92 of ammonium persulfate and an alkaline solution, or as shown in FIG. 4B, the mixed reaction solution is guided via the line 93 and the pump 94. 92 flows into the metal pipe body 80 to contact the capillary structure, and the mixed reaction solution 92 oxidizes the inner pipe wall of the metal pipe body 80. The alkaline solution may be sodium hydroxide or potassium hydroxide, but is not limited thereto. The ammonium persulfate can also be replaced by potassium persulfate or sodium persulfate. Taking the mixed reaction solution of ammonium persulfate and sodium hydroxide as an example, the concentration, concentration ratio, reaction time and reaction temperature of sodium hydroxide and ammonium persulfate are adjusted during the reaction with the inner wall of the metal pipe body. With the parameters, the surface of the capillary structure of the inner tube wall of the metal pipe body can be modified into an oxidized structure surface. Taking a copper tube as an example, the concentration of sodium hydroxide can be between 0.25 and 5 M, and the concentration ratio of sodium hydroxide to ammonium persulfate (NaOH/(NH ₄ ) ₂ S ₂ O ₈ = 4 to 50) and reaction time. Between 0~12 hours and a reaction temperature of 0-70 °C, the surface of the oxidized structure is a surface formed by a blue copper hydroxide microstructure, and the reaction equation is as shown in the following formula (1). It should be noted that sodium hydroxide can be replaced by potassium hydroxide.

Cu+(NH ₄ ) ₂ S ₂ O ₈ +NaOH → Cu(OH) ₂ +2Na ₂ SO ₄ +2NH ₃ +2H ₂ O...(1)

In another embodiment, the surface of the oxidized structure may further dehydrate the blue copper hydroxide microstructure into a black copper oxide microstructure, and the reaction equation is as shown in the following formula (2).

Cu+(NH ₄ ) ₂ S ₂ O ₈ +NaOH → Cu(OH) ₂ +2Na ₂ SO ₄ +2NH ₃ +2H ₂ O Cu(OH) ₂ → CuO+H ₂ O...(2)

Another embodiment of the oxidation of the step 21 is substantially similar to the methods of the above formulas (1) and (2), except that the present embodiment adjusts the composition of the mixed reaction solution to potassium persulfate and potassium hydroxide. The surface concentration, the ratio, the reaction time and the reaction temperature of the solution oxidize the surface of the copper to a microstructure having blue copper hydroxide, as shown by the following formula (3). It should be noted that potassium persulfate can be replaced by sodium persulfate, and potassium hydroxide can also be replaced by sodium hydroxide.

Cu+K ₂ S ₂ O ₈ +2 KOH → Cu(OH) ₂ +2K ₂ SO ₄ (3)

In another embodiment, the oxidized structure surface may further dehydrate the blue copper hydroxide microstructure into a black copper oxide microstructure, and the reaction equation is as shown in the following formula (4).

Cu+K ₂ S ₂ O ₈ +2 KOH → Cu(OH) ₂ +2K ₂ SO ₄ Cu(OH) ₂ → CuO+H ₂ O...(4)

In addition, in step 21, another embodiment of the oxidation is performed by means of temperature treatment, that is, the oxidation mode of the embodiment does not need to be oxidized by the reaction solution, but utilizes temperature and time. Control to achieve the effect of oxidation. In one embodiment, the metal pipe body having the conventional capillary structure is placed in a high-temperature oven in an oxygen-containing environment (for example, a high-oxygen environment) in an unsealed state, and the oxidation temperature and the oxidation time are performed. The capillary structure of the inner tube wall of the metal pipe body is modified into a metal oxide. Take the copper tube as an example, it can be placed in the temperature range of 250~450 °C, The surface of the inner wall of the copper tube is modified to copper oxide at a time of 0.5 to 6 hours, as shown in the following formula (5).

The surface of the oxidized structure formed by the above formulas (1) to (5) is exemplified by copper, and the contact angle between the water and the oxidized structure formed by the surface microstructure is almost zero, which increases the oxidative modification. The hydrophilicity of the capillary structure. Returning to FIG. 1 , after step 21, step 22 may be further performed to perform a second oxidation reaction or a first oxidation of a portion of the inner tube wall of the metal tube body. The surface of the structure is modified to form a second oxidized structure surface having a second contact angle. In this embodiment, the second contact angle is greater than the first contact angle. Please refer to FIG. 5A, which is a schematic cross-sectional view of the metal pipe body according to FIG. 2 after the step 21. The area shown by the plurality of dots in the figure represents the first oxidized structure 82 on the inner tube wall. Taking the copper tube as an example, in the step 22, the oxidation method is performed according to the reaction formulas of the above formulas (1) to (5), and then the second oxidation mode is performed, which is the metal tube body 80. Part of region 800, impregnated with fluoroalkyl siloxane (CF ₃ (CF ₂ ) _n (CH ₂ ) ₂ Si(OCH ₂ CH ₃ ) ₃ or CF ₃ (CF ₂ ) _n (CH ₂ ) ₂ Si (OCH ₃ ) ₃ ], fluoroalkyltrichloromethane [CF ₃ (CF ₂ ) _n (CH ₂ ) ₂ SiCl ₃ ], fluoroalkyl dimethylchlorodecane [CF ₃ (CF ₂ ) _n (CH ₂ ) ₂ SiCl(CH ₂ ) ₂ ], alkyl alkane [CH ₃ (CH ₂ ) _n Si(OCH ₂ CH ₃ ) ₃ or CH ₃ (CH ₂ ) _n Si(OCH ₃ ) ₃ ], alkyl Trichlorodecane [CH ₃ (CH ₂ ) _n SiCl ₃ ], alkyl dimethyl chlorodecane [CH ₃ (CH ₂ ) _n SiCl(CH ₂ ) ₂ ] or thiol [CH ₃ (CH ₂ ) _n SH] The diluted solution (ex: 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane concentration of 1w.t.% ethanol solution) in the reaction for 0 ~ 1hr, removed and washed and placed in an oven to dry (25 ~ 150 ° C), so that The first oxidized structure surface 82 is modified to form a second oxidized structure surface 83 having a long carbon chain structure 830 as shown in FIG. 5B. The long carbon chain structure 830 can be a long carbon chain fluoroalkyl or a long carbon chain alkyl group. In addition, the second oxidized structure surface 83 has a second contact angle with the working fluid (eg, water), the second contact angle being greater than the first contact angle.

As shown in Fig. 5C, the hatched area inside the tube wall of the region 800 represents the second oxidized structure 83 formed on the inner tube wall. After the step 21, the oxidized structure formed by the region 801 can be regarded as a hydrophilic oxidized structure, and after the step 22, the oxidized structure formed by the region 800 can be regarded as a hydrophobic oxidized structure with respect to the oxidized structure of the region 801. Returning to Figure 1, the metal tube is finally subjected to a processing procedure in step 23 to form a heat pipe. In this step 23, the processing program can be divided into several stages. The first stage first closes one end of the metal pipe body, then in the second stage, the metal pipe body is evacuated, and then the third stage is to work the fluid. For example, water is filled into the metal pipe body closed at one end, and then the other end of the metal pipe body is closed in the fourth stage to form a structure in which both ends are closed. Finally, the heat pipe is surface-cleaned to form a heat pipe. After step 23, in another embodiment, the heat pipe can be shaped to form heat pipes of various shapes, such as U-shaped tubes, L-shaped tubes or annular tubes.

Please refer to FIG. 6A, which is a schematic flow chart of another embodiment of the present disclosure. In this embodiment, the capillary structure of the inner wall of the metal tube is modified to an oxidized structure mainly by heating. The method 3 also provides, in step 30, a metal tube body which is not closed at both ends, and the characteristic of the metal tube body As described in the metal pipe body of the foregoing step 20, no further details are provided herein. Then, in step 31, the metal tube body is placed in an oxygen-containing environment having a first oxidation temperature, and the surface of the first oxidized structure is obtained after a oxidizing time. Taking a copper tube as an example, the first oxidation temperature is 80 ° C to 150 ° C, and the first oxidation time is 0 to 10 hours. The first oxidized structure formed through step 31 has a first contact angle with the working fluid. In this embodiment, the metal pipe body is a copper pipe, and thus the first oxidation structure is cuprous oxide. Then, in step 32, a portion of the metal tube body having the surface of the first oxidized structure is subjected to another oxidation treatment to form a second oxidized structure surface. As shown in FIG. 6B, in the present embodiment, the oxidation treatment is performed by placing the surface having the first oxidized structure in the region 802 of the metal pipe body 80 in an oxygen-containing environment having a second oxidation temperature. The second oxidized structure is obtained after a second oxidation time. In this embodiment, the second oxidation temperature is from 250 ° C to 450 ° C, and the second oxidation time is from 0.5 to 6 hours. The second oxidized structure surface 85 obtained in step 32 has a second contact angle which is smaller than the first oxidized structure surface 84 in the other region 803 (as in the region having a plurality of points in FIG. 6B) The first contact angle. It is to be noted that if the second oxidized structure 85 is formed by heating (as in the oblique line region in the tube wall in FIG. 6B), in order to prevent the heat conduction effect from affecting the region 803 having the first oxidized structure, it is possible to When the 802 is subjected to the heat treatment, the region 803 is simultaneously cooled, for example, an ice bath or cooled by a liquid gas to prevent the heat generated when the region 802 is heated from affecting the region 803 via the heat conduction effect. Further, in addition to the use of heat, the oxidation method of the step 32 can also be carried out by using the above formulas (1) to (4), that is, by mixing the reaction solution and the metal by means of impregnation. The first oxidized structure surface contact is formed in the region 802 of the tube body 80, and the metal tube body having the first oxidized structure is modified by the mixed reaction solution to form the second oxidized structure surface 85. The second oxidized structure surface 85 can be a metal oxide or a metal hydroxide such as copper oxide or copper hydroxide. Returning to Figure 6A, after step 32, the metal tube is also subjected to a processing procedure in step 33 to form a heat pipe. The processing program is divided into several stages. The first stage first closes one end of the metal pipe body, then in the second stage, the metal pipe body is evacuated, and then the third stage is to fill the working fluid, for example, water to the one end. In the closed metal pipe body, the other end of the metal pipe body is then closed in a fourth stage to form a structure in which both ends are closed. Finally, the heat pipe is surface-treated to form a heat pipe. After step 33, in another embodiment, the heat pipe can be shaped to form heat pipes of various shapes, such as U-shaped tubes, L-shaped tubes or annular tubes.

Although the flow shown in Fig. 1 and Fig. 6A is a method of producing an oxidized structure having different contact angles in the same metal pipe body, in practice, it is not necessary to simultaneously employ a two-stage oxidation process. In one embodiment, as shown in FIG. 7A, a metal tube having a capillary structure, such as a copper tube, which is not closed at both ends, may be provided in step 40. Next, the specific region of the metal pipe body is oxidized in step 41 to the capillary structure on the inner wall of the metal pipe of the region to form a hydrophilic region. The manner of the step 41 is as described in the foregoing step 21, and details are not described herein. Then, one end of the metal pipe body is closed, and then the metal pipe body is vacuumed, and then a working fluid such as water is filled into the metal pipe body closed at one end, and then the other end of the metal pipe body is closed to form Structure closed at both ends, and finally surface treatment and cleaning to shape Heated into a tube. In another embodiment, as shown in FIG. 7B, step 50 may also be provided to provide a metal tube having a capillary structure that is not closed at both ends, such as a copper tube. Next, in step 51, the capillary structure of the metal tube having a specific region is oxidized to form a hydrophobic region. The manner of the step 51 is as described in the foregoing step 31 or the foregoing steps 21 to 22, and details are not described herein. Wherein, if the method of heating the metal pipe body in the foregoing step 31 is carried out, the region oxidized not to be heated may be cooled by means of cooling, for example, an ice bath or a liquid gas to avoid heating the specific region. When an oxidized structure is formed, the heat transfer effect affects other regions. Then, one end of the metal pipe body is closed, and then the metal pipe body is vacuumed, and then a working fluid such as water is filled into the metal pipe body closed at one end, and then the other end of the metal pipe body is closed to form The structure is closed at both ends, and finally surface treatment and cleaning are performed to form a heat pipe. Generally speaking, in the case of a copper material, if the heat pipe is simply a capillary structure, the contact angle with a working fluid such as water is between 70 and 80 degrees, but the oxidation formed by the oxidizing method of the present disclosure. The structure can make the contact angle between the oxidized structure and the water in the hydrophilic region less than 70 degrees, so the hydrophilic region can serve as the evaporation region of the heat pipe; and the contact angle of the oxidized structure with water in the hydrophobic region is greater than 80 degrees. Therefore, the hydrophobic region can serve as a condensation zone for the heat pipe.

Please refer to FIG. 8 , which is a schematic flow chart of another embodiment of the heat pipe processing method of the present disclosure. In this embodiment, the method 6 includes the step 60 of providing a metal tube body that is not closed at both ends. As shown in Fig. 9A, the figure is a schematic cross-sectional view of a metal pipe body. The inner wall of the metal pipe body 70 has a capillary structure 71 (such as a region having a plurality of points in FIG. 9A), the metal pipe body The inner wall of 70 can be divided into an evaporation zone 700, a condensation zone 701, and a thermal insulation zone 702. Next, in step 61, the capillary structure 71 in the evaporation zone 700 is oxidized to modify the capillary structure 71 to form a first oxidation structure having a first contact angle. In step 61, the manner of oxidizing may be performed by the three methods disclosed in the foregoing step 21 to form a highly hydrophilic oxidized structure. In one embodiment, the first contact angle is less than 70 degrees. Next, in step 62, the capillary structure 71 in the condensation zone 701 is oxidized to modify the capillary structure 71 to form a second oxidation structure having a second contact angle. In step 62, the oxidation may be performed by the manner disclosed in the foregoing step 31 or by the steps 21 and 22 to form a hydrophobic oxidized structure. In one embodiment, the second contact angle of the hydrophobic oxidized structure More than 80 degrees. Then, in step 63, the metal pipe body is subjected to a processing procedure to form a heat pipe. The processing program is divided into several stages. The first stage first closes one end of the metal pipe body, then in the second stage, the metal pipe body is evacuated, and then the third stage is to fill the working fluid, for example, water to the one end. In the closed metal pipe body, the other end of the metal pipe body is then closed in a fourth stage to form a structure in which both ends are closed. Finally, the heat pipe is surface-treated to form a heat pipe. Please refer to FIG. 9B, which is a schematic cross-sectional view of the heat pipe formed in step 63. The oxidized structure surface 72 (e.g., the hatched region within the tube wall in the evaporation zone 700 in Figure 9B) having an oxidized structure surface therein is a hydrophilic oxidized structure that can produce a contact angle of less than 70 degrees. The oxidized structure surface 73 (e.g., the hatched area in the tube wall in the condensing zone 701 in Fig. 9B) in the condensing zone 701 is a hydrophobic oxidizing structure which can produce a contact angle of more than 80 degrees.

Please refer to the following formula (6), which is the calculation equation for the capillary pressure difference in the heat pipe.

Where ΔP is the capillary pressure difference, σ is the surface tension, θ _e is the contact angle of the working fluid with the capillary structure in the evaporation zone, θ _c is the contact angle of the working fluid with the capillary structure in the condensation zone, and r is the capillary radius. Evap represents the evaporation zone and cond represents the condensation zone. The filling capacity of the traditional heat pipe working fluid will be as high as that of the capillary structure. When the evaporation zone is heated to volatilize the working fluid, the contact angle of the working fluid in the evaporation zone is lower than the contact angle of the condensation zone, causing the capillary pressure difference to operate. . Different capillary structures have different capillary radii. In order to improve the capillary pressure difference during operation, it can be achieved by changing the design of the capillary structure. In addition, the capillary structure in the general heat pipe is a uniform material, so the contact angle between the working fluid and the capillary structure is Fixed value.

In contrast, according to the method of the present disclosure, if the same capillary structure radius is used, and the surface tension of the working fluid is not changed, the chemical fluid is modified to make the working fluid have different wettability in the evaporation zone and the condensation zone, that is, to change evaporation. The contact angle between the zone and the condensing zone, brought into the formula (6), can also be found to achieve the effect of increasing the capillary pressure difference and the maximum heat transfer amount. Taking the embodiment of FIG. 9B of the present disclosure as an example, in this embodiment, after the foregoing oxidation process, the oxidized structure surface 72 of the evaporation zone 700 can reach a contact angle of about 57 degrees, and the oxidized structure of the condensing zone 701 The surface 73 can reach a contact angle of about 137 degrees, so that the working fluid (for example, water) in the heat pipe 7 can be evaporated by chemical surface modification without changing the surface tension of the working fluid in the heat pipe. The zone 700 has a different wettability from the condensing zone 701, thereby increasing the capillary pressure differential to produce the maximum heat transfer.

For example, in one embodiment, the working fluid is water, and the pipe body is made of copper heat pipe, and the heat pipe has a groove capillary structure as an example, the total pipe length is 25 cm, the pipe diameter is 6 cm, and the groove height is 0.34 cm. The width is 0.21 cm and the total number of grooves is 55. By chemical surface modification, the contact angle of water and copper can be raised to a contact angle of 137 degrees in the condensation zone, if the evaporation zone is fixed to the contact angle of water and copper. 78 degrees, and nested into the formula to estimate the maximum heat transfer, the maximum heat transfer of this heat pipe is 128.3W. Compared with the traditional unmodified heat pipe, the maximum heat transfer capacity that can be achieved is only 28.4W, which can distinguish the more heat transfer from the chemical structure of the chemically modified foam.

The above description is only intended to describe the preferred embodiments or embodiments of the present invention, which are not intended to limit the scope of the invention. That is, the equivalent changes and modifications made in accordance with the scope of the patent application of the present invention or the scope of the invention are covered by the scope of the invention.

2‧‧‧ Heat pipe processing method

20~23‧‧‧Steps

3‧‧‧ Heat pipe processing method

30~33‧‧‧Steps

40~41‧‧‧Steps

50~51‧‧‧Steps

6‧‧‧ Heat pipe processing method

60~63‧‧‧Steps

7‧‧‧heat pipe

70‧‧‧Metal pipe body

700‧‧‧Evaporation zone

701‧‧‧Condensation zone

702‧‧‧Insulation zone

71‧‧‧Capillary structure

72, 73‧‧‧ oxidized structure surface

80‧‧‧Metal pipe body

800, 801, 802, 803‧‧‧ areas

81‧‧‧Capillary structure

82, 84‧‧‧ First oxidized structure surface

83, 85‧‧‧Second oxidized structure surface

830‧‧‧Long carbon chain structure

90a~90c‧‧‧Metal surface

91‧‧‧Working fluid

92‧‧‧ mixed reaction solution

93‧‧‧pipe

94‧‧‧ pump

FIG. 1 is a schematic flow chart of a first embodiment of a heat pipe processing method according to the present disclosure.

Figure 2 is a side elevational cross-sectional view of the metal pipe body of the present disclosure.

Figures 3A to 3C are schematic views of contact angles.

4A and 4B are schematic views showing the inner wall of a metal tube oxidized by a mixed reaction solution according to the present disclosure.

Figure 5A is a metal tube section after the oxidation process of step 21. Schematic diagram.

Figure 5B is a schematic diagram of an oxidized structure having a long carbon chain formed after the oxidation process of Step 22.

Fig. 5C is a schematic cross-sectional view showing the structure of the heat pipe formed by the first embodiment of the heat pipe processing method.

Figure 6A is a schematic flow chart of the second embodiment of the heat pipe processing method.

Figure 6B is a schematic cross-sectional view showing the structure of the heat pipe formed by the second embodiment of the heat pipe processing method.

7A and 7B are schematic views showing the flow of other embodiments of the heat pipe processing method.

Figure 8 is a schematic flow chart of another embodiment of the heat pipe processing method of the present disclosure.

Figure 9A is a schematic cross-sectional view of a metal pipe body.

Section 9B is a schematic cross-sectional view of the heat pipe formed by the heat pipe processing method of Fig. 8.

2‧‧‧ Heat pipe processing method

20~23‧‧‧Steps

Claims (3)

A heat pipe processing method comprising the steps of: providing a metal pipe body having an opening at both ends, the inner wall of the metal pipe having a capillary structure surface, the material of the metal pipe body being copper, the metal pipe body The inner wall can be divided into an evaporation zone, a condensation zone and a heat insulation zone; the capillary structure of the inner wall of the metal pipe is modified by a mixed reaction solution to form a surface of the first oxidation structure, so that the evaporation of the inner wall of the metal pipe a capillary structure having the first oxidized structure, the surface of the first oxidized structure being a surface formed by a metal hydroxide or a metal oxide; wherein the surface of the first oxidized structure and a working fluid have a first Contact angle; modifying the capillary structure of the inner wall of the metal tube with the mixed reaction solution to form the surface of the first oxidation structure comprises the steps of: providing the mixed reaction solution, wherein the mixed reaction solution is selected as ammonium persulfate and a mixed solution of an alkaline solution, one of a mixed solution of potassium persulfate and the alkaline solution, the alkaline solution being sodium hydroxide or potassium hydroxide, The concentration of the solution is between 0.25 and 5 M, and the ratio of the concentration of the alkaline solution to ammonium persulfate or potassium hydroxide is 4 to 50; and the metal tube system is immersed in the mixed reaction solution, and the mixed reaction solution is The surface of the inner wall of the metal pipe is oxidized to form the surface of the first oxidized structure, the reaction time is between 0.01 and 12 hours, and the reaction temperature is 10 to 70 ° C; and the inner wall of the metal pipe is treated by an alkyl group-containing solution. Condensation zone The capillary structure of the first oxidized structure is modified to form a second oxidized structure surface having a long carbon chain alkyl structure, the second oxidized structure having a second contact angle with the working fluid, the second The contact angle is greater than the first contact angle, wherein the reaction time for oxidizing the capillary structure in the condensation zone is 0.01 to 1 hour, and after being taken out, it is washed and placed in an oven to be dried at a temperature of 25 to 150 ° C, and the alkyl group is contained. The solution is a fluoroalkyl siloxane, a fluoroalkyl trichloro decane, a fluoroalkyl dimethyl chloro decane, an alkyl oxa oxane, an alkyl trichloro decane, an alkyl dimethyl chloro decane or an alkane. Diluted solution of thiol. The heat pipe processing method of claim 1, wherein the first contact angle of the surface of the first oxidized structure of the evaporation zone is between 1 and 70 degrees, and the surface of the second oxidized structure of the condensation zone The second contact angle is between 80 and 150 degrees. The heat pipe processing method according to claim 1, wherein the long carbon chain-containing alkyl structure is a microstructure of a long carbon chain fluoroalkyl group or a long carbon chain alkyl group.