CN110763057A - Ultrathin heat pipe and manufacturing method thereof - Google Patents

Abstract

The invention discloses an ultrathin heat pipe and a manufacturing method thereof.A positioning rod with a conical end is used as a guide, a wick capillary structure which is bent and attached to the surface of the positioning rod is arranged in a metal pipe shell of the heat pipe, and a plurality of wick capillary structures which are distributed in an array are formed on the inner wall of the pipe shell through sintering. The invention can form a plurality of capillary structures which are distributed, increase the heat transfer area, improve the heat transfer efficiency, has flexible operation and greatly reduced processing difficulty, and is not easy to cause copper wires to hang on the pipe orifice to cause the damage of the capillary structures, thereby not reducing the capillary capacity of the capillary structures and greatly improving the heat transfer efficiency of the heat pipe.

Description

A kind of ultra-thin heat pipe and its production method

technical field

The invention belongs to the field of heat pipe temperature equalizing plates, and particularly relates to a manufacturing process of an ultra-thin heat pipe.

Background technique

With the advancement of science and technology, today's electronic products are developing in the direction of high function, high efficiency, and thinness. Especially at present, 5G is the future development trend of the consumer electronics field. The computing power of the chip is significantly improved, and its power consumption is also reduced. Much higher than 4G chips, the demand for heat dissipation in consumer electronics products will become stronger in the future. The increase in chip power consumption has greatly increased the heat generated in the unit area. How to quickly dissipate the heat of the chip has always been a difficulty and bottleneck in the industry. Therefore, superconducting materials and heat-dissipating materials that quickly conduct heat from chips need to be continuously improved and improved to solve the problem of heat dissipation of chips, so as to promote the continuous development of science and technology.

The heat pipe has the advantages of light weight, high thermal conductivity, high reliability, maintenance-free, no noise, etc. It is a recyclable green technology. Compared with conventional copper or aluminum sheets, the thermal conductivity of heat pipes is more than 10 times higher, and the high thermal conductivity of heat pipes is very suitable for heat dissipation of concentrated heat sources. The existing heat pipe manufacturing process is complicated, and the capillary structure is often used for direct placement. However, the small diameter of the pipe leads to greater processing accuracy and difficulty, and the efficiency is low; The gap is filled with metal powder and sintered to form a capillary structure on the surface of the tube shell, but this method cannot form a capillary structure with the desired shape (such as lines, or multi-branched arrangements, etc.).

SUMMARY OF THE INVENTION

In view of the above-mentioned existing problems, the present invention proposes a multi-branched arrangement structure of an ultra-thin heat pipe liquid absorbing core and a manufacturing method thereof, and specifically proposes the following technical solutions:

An ultra-thin heat pipe, characterized in that it includes:

a metal tube shell, the metal tube shell has a length along the axial direction, and a closed cavity is formed inside;

The capillary structure of the liquid-absorbing core, the capillary structure of the liquid-absorbing core is attached to the inner wall of the metal tube shell in a multi-branch arrangement structure, and the capillary structure of the liquid-absorbing core is an even number of metal wires;

The working fluid is sealed in the closed cavity of the metal tube shell.

A method for making an ultra-thin heat pipe, comprising the following steps:

providing a metal tube shell, the metal tube shell has a first end and a second end respectively open, the first end of the heat pipe shell is contracted, and the second end remains unchanged;

A positioning rod is provided, the outer diameter of the positioning rod is smaller than the inner diameter of the metal tube shell, and one end of the positioning rod is tapered;

providing a capillary structure of the liquid-absorbent core, the capillary structure of the liquid-absorbent core is bent at the conical top of the positioning rod, and the capillary structure of the liquid-absorbent core is bent and attached to the outer surface of the positioning rod;

The positioning rod with the capillary structure of the bent liquid-absorbing wick attached to the outer surface is inserted into the metal tube shell through the opening of the second end of the unshrunk head, and the tapered end of the positioning rod is located at the shrinking head of the metal tube shell. at the first end;

sintering;

After sintering, the positioning rod is pulled out from the metal tube shell.

Further, the manufacturing method of the ultra-thin heat pipe further includes: after the capillary structures of the plurality of liquid absorbing cores are bent and attached to the surface of the positioning rod, the positioning rod is placed in the metal tube shell. Therefore, multiple groups of capillary structures of the liquid-absorbing wick that are uniformly or non-uniformly distributed in the circumferential direction without overlapping can be formed on the inner wall of the metal tube shell by sintering.

Further, the manufacturing method of the ultra-thin heat pipe further includes, after the sintering step, the steps of shrinking the second end and welding the shrinking, refrigerant injection, degassing and packaging; The first end of the heat pipe shell is injected into the shell cavity in which the capillary structure of the liquid absorbing core is inserted; the degassing is vacuum degassing; and the packaging adopts welding packaging.

Further, the metal tube shell is one of copper, aluminum, stainless steel, titanium or its alloy; the cross-section of the metal tube shell is circular, oval or rectangular.

Further, the material of the metal wire of the capillary structure of the liquid-absorbing core is copper, nickel, zinc, and silver; the capillary structure of the liquid-absorbing core can be processed by techniques such as etching, laser, machining, wire drawing, sintering, printing, 3D printing, etc. form.

Further, the working fluid is a cooling medium, and the cooling medium is fluorinated liquid, alcohol, acetone, water, 7100, and refrigerants R22 and 1233.

The beneficial effects of the present invention are:

Because the tail end of the tube is not narrowed and the diameter of the process of the invention is larger, the diameter of the tube opening after the tube is reduced by several times, the capillary structure can be easily placed, and the efficiency can be greatly improved; The required liquid-absorbing core structure is placed in the tube shell according to the needs, which can form a multi-branched capillary structure, increase the heat transfer area, improve the heat transfer efficiency, the operation is flexible, the processing difficulty is greatly reduced, and it is not easy to cause the copper wire to hang. At the nozzle, the capillary structure is damaged, so that the capillary capacity of the capillary structure will not be reduced, and the heat transfer efficiency of the heat pipe will be greatly improved.

Description of drawings

1 is a schematic diagram of the materials required for the method for making an ultra-thin heat pipe of the present invention;

FIG. 2 is a schematic diagram of steps of a method for manufacturing an ultra-thin heat pipe of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are a part of the embodiments of the present invention, not all of the embodiments, and are only used to explain the present invention, but not to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Fig. 1 schematically shows the materials required for a method of manufacturing an ultra-thin heat pipe of the present invention, providing a metal tube shell 1, the metal tube shell has a first end 11 and a second end 12 respectively opened, and the heat pipe The first end 11 of the shell 1 is retracted, and the second end 12 remains unchanged. The metal tube shell 1 has a cavity inside for forming the wick capillary structure 3 and encapsulating the working fluid required for heat transfer; a positioning rod is provided 2. The outer diameter of the positioning rod 2 is smaller than the inner diameter of the metal tube shell 1, and one end of the positioning rod 2 is tapered.

FIG. 2 schematically shows the operation steps of an ultra-thin heat pipe manufacturing method of the present invention, and provides a liquid-absorbent wick capillary structure 3 , and the liquid-absorbent wick capillary structure 3 is formed on the conical top of the positioning rod 2 . Bending, the liquid-absorbent core capillary structure 3 is bent and attached to the outer surface of the positioning rod 2; The second end 12 of the head is opened into the metal tube shell 1, and the tapered end of the positioning rod is located at the first end 11 of the shrinking head of the metal tube shell 1; sintering; after sintering, the positioning rod 2 is removed from the metal tube. The capillary structure 3 of the liquid-absorbing wick is combined with the inner wall of the metal tube shell 1 by sintering, and is left on the inner wall surface to form the desired multi-branched capillary structure. After the sintering step, it also includes the steps of shrinking the second end 12 and performing welding sealing, refrigerant injection, degassing and encapsulation; into the tube-shell cavity with the capillary structure of the liquid absorbing core; the degassing is vacuum degassing; the packaging adopts welding packaging.

In another embodiment, after the first group of capillary structures 3 for liquid-absorbent wicks are bent, multiple groups of capillary structures for liquid-absorbent wicks can be bent in the same manner as required, so that the multiple groups of capillary structures for liquid-absorbent wicks are bent The positioning rods 2 are uniformly or non-uniformly arranged without overlapping in the circumferential direction of the outer surface of the positioning rods 2 . Then, the positioning rods 2 that are bent and arranged with multiple groups of capillary structures of the liquid-absorbing core are inserted into the metal tube shell 1 through the opening of the second end 12 of the unshrunk head of the metal tube shell 1. After sintering, the positioning rods 2 are removed from the metal tube. When the shell 1 is pulled out, the inner wall of the metal tube shell 1 forms a plurality of groups of capillary structures of liquid-absorbent wicks that are uniformly or non-uniformly distributed along the circumferential direction without overlapping.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", The orientation or positional relationship indicated by "two ends", "both sides", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated elements must have The particular orientation, or construction and operation in the particular orientation, is therefore not to be construed as a limitation of the invention.

The foregoing are merely some of the embodiments of the present invention. For those of ordinary skill in the art, without departing from the inventive concept of the present invention, several modifications and improvements can be made, which all belong to the protection scope of the present invention.

Claims (10)

1. An ultra-thin heat pipe, comprising:

the metal tube shell is provided with a length along the axial direction, and a closed cavity is formed inside the metal tube shell;

the liquid absorption core capillary structure is of a plurality of arrangement structures and is attached to the inner wall of the metal pipe shell, and the liquid absorption core capillary structure is an even number of metal wires;

a working fluid sealed within the enclosed cavity of the metal envelope.

2. An ultra-thin heat pipe as claimed in claim 1, wherein the metal pipe case is made of one of copper material, aluminum material, stainless steel, titanium material or alloy thereof; the cross section of the metal pipe shell is circular, elliptical or rectangular.

3. The ultra-thin heat pipe of any of claims 1 or 2 wherein the wire of the wick capillary structure is copper, nickel, zinc, silver; the wick capillary structure can be formed by etching, laser, machining, wire drawing, sintering, printing, 3D printing and other technologies.

4. The ultra-thin heat pipe of any one of claims 1 or 2, wherein the working fluid is a refrigerant medium, and the refrigerant medium is fluorinated liquid, alcohol, acetone, water, 7100, R22, 1233.

5. A method for manufacturing an ultra-thin heat pipe as claimed in claims 1-4, comprising the steps of:

providing a metal pipe shell, wherein the metal pipe shell is provided with a first end and a second end which are respectively provided with openings, the first end of the heat pipe shell is contracted, and the second end of the heat pipe shell is kept unchanged;

providing a positioning rod, wherein the outer diameter of the positioning rod is smaller than the inner diameter of the metal pipe shell, and one end of the positioning rod is conical;

providing a wick capillary structure, wherein the wick capillary structure forms a bend at the conical top of the positioning rod, and the wick capillary structure is attached to the outer surface of the positioning rod after being bent;

placing a positioning rod with a bent wick capillary structure attached to the outer surface into the metal tube shell through a second end opening of the non-shrinking head, wherein the conical end of the positioning rod is positioned at the first end of the shrinking head of the metal tube shell;

sintering;

and after sintering, the positioning rod is extracted from the metal tube shell.

6. The method of claim 5, wherein the wick capillary structures are at least one group, and after the first group of wick capillary structures are bent and attached to the outer surface of the positioning rod, the remaining groups of wick capillary structures are bent and attached to the outer surface of the positioning rod in the same manner.

7. The method of claim 5 or 6, further comprising, after the sintering step, the steps of necking the second end and welding, injecting a cooling medium, degassing, and encapsulating the necked portion; the refrigerant is injected into the tube shell cavity with the wick capillary structure through the first end of the heat pipe shell; the degassing is vacuum degassing; the packaging adopts welding packaging.

8. A method for making an ultra-thin heat pipe as claimed in claim 7, wherein the metal casing is made of one of copper, aluminum, stainless steel, titanium or their alloys; the cross section of the metal pipe shell is circular, elliptical or rectangular.

9. A method for fabricating an ultra-thin heat pipe as claimed in claim 7, wherein the wick is a capillary structure of copper, nickel, zinc, or silver; the wick capillary structure can be formed by etching, laser, machining, wire drawing, sintering, printing, 3D printing and other technologies.

10. A method for fabricating an ultra-thin heat pipe as claimed in claim 7, wherein the working fluid is a refrigerant medium, and the refrigerant medium is fluorinated liquid, alcohol, acetone, water, 7100, and refrigerant R22, 1233.

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