Heat transfer device and method for manufacturing the same

Abstract

The invention provides a heat transfer device and a manufacturing method thereof, and the method comprises the following steps: metal powder is provided, the metal powder is sintered once to form a plurality of sintered blocks, and each sintered block is provided with a plurality of first pores; a heat conduction shell is provided, the multiple sintering blocks are subjected to secondary sintering to form a capillary structure, the capillary structure is combined with the heat conduction shell, the sintering blocks cover at least one part of the inner wall of the heat conduction shell, multiple second holes are formed among the multiple sintering blocks, and the first holes are smaller than the second holes; the heat conduction shell is filled with working fluid; the heat conduction shell is closed, a closed cavity is formed in the heat conduction shell, and the capillary structure and the working fluid are located in the closed cavity.

Description

Technical Field

[0001] The present application provides a phase change heat transfer device with a capillary structure formed by secondary sintering and a manufacturing method thereof. Background Art

[0002] Phase change heat transfer devices such as heat pipes and temperature equalizers are generally hollow bodies made of metal, and contain easily boiling liquid working fluid. The principle of the phase change heat transfer device is that a part of the hollow body contacts the heat source and absorbs heat energy into the liquid working fluid at this part, thereby causing the liquid working fluid at this part to vaporize and diffuse throughout the hollow body. When the working fluid is away from the heat source, it condenses and flows back to the heat source. In order to accelerate the backflow of the working fluid, a capillary structure passing through the heat source is generally configured in the hollow body. The capillary structure is metal powder sintered on the inner wall of the hollow body. The sintered metal powder has pores and can absorb the liquid working fluid to make it flow back to the heat source.

[0003] The existing capillary structure formed by direct sintering of metal powder has too dense pores, resulting in low permeability and poor air permeability. Therefore, it is difficult to generate sufficient pressure difference to drive the liquid working fluid adsorbed therein to flow smoothly. Its reflux efficiency is difficult to improve, which easily causes dry burning of the working fluid at the heat source.

[0004] In view of this, the applicant has conducted intensive research on the above-mentioned prior art and applied theoretical knowledge to try its best to solve the above-mentioned problems, which has become the goal of the applicant's improvement. Summary of the invention

[0005] The present application provides a phase change heat transfer device with a capillary structure formed by secondary sintering and a manufacturing method thereof.

[0006] The present application provides a heat transfer device, which includes a heat-conducting shell capillary structure and a working fluid. The heat-conducting shell has a closed chamber. The capillary structure is disposed in the closed chamber, and includes a plurality of sintered lumps, which cover at least a portion of the inner wall of the heat-conducting shell. Each sintered lump is formed by sintering metal powder and has a plurality of first pores in each sintered lump. A plurality of second pores are formed between the plurality of sintered lumps, wherein each first pore is smaller than each second pore. The working fluid is contained in the closed chamber.

[0007] In one embodiment of the present application, each sintered agglomerate is formed by sintering copper powder or aluminum powder.

[0008] In one embodiment of the present application, the heat conductive housing is made of copper or aluminum.

[0009] In one embodiment of the present application, the heat-conducting outer shell is in a tubular shape, and the capillary structure is arranged along the longitudinal extension of the heat-conducting outer shell.

[0010] In one embodiment of the present application, the heat-conducting outer shell is in the shape of a hollow flat plate, and the capillary structure is disposed in the closed chamber corresponding to one side of the heat-conducting outer shell.

[0011] The present application also provides a method for manufacturing a heat transfer device, which includes the following steps: providing metal powder, sintering the metal powder once to form a plurality of sintered lumps, each of which has a plurality of first pores; providing a heat-conducting shell, sintering the plurality of sintered lumps twice to form a capillary structure, and combining the capillary structure with the heat-conducting shell, wherein the sintered lumps cover at least a portion of the inner wall of the heat-conducting shell, and a plurality of second pores are formed between the plurality of sintered lumps, each of which is smaller than each of the second pores; filling the heat-conducting shell with a working fluid; and sealing the heat-conducting shell to form a closed chamber in the heat-conducting shell, so that the capillary structure and the working fluid are located in the closed chamber.

[0012] In one embodiment of the present application, the metal powder is copper powder or aluminum powder.

[0013] In one embodiment of the present application, the heat conductive housing is made of copper or aluminum.

[0014] In one embodiment of the present application, the heat conductive housing is tubular, and the capillary structure is arranged along the longitudinal extension of the heat conductive housing.

[0015] In one embodiment of the present application, the heat-conducting shell is in the shape of a hollow flat plate, and the capillary structure is disposed in the closed chamber corresponding to one side of the heat-conducting shell.

[0016] The manufacturing method of the heat transfer device of the present application has a secondary sintering step. First, a certain amount of solid metal powder is sintered into a sintered mass. Then, a certain amount of the sintered mass is sintered on the inner wall of the heat conductive shell to form a capillary structure in the heat transfer device. The metal powder is densely stacked and the gaps between the sintered masses are large. In other words, the first pores between the particles of the metal powder are smaller than the second pores between the sintered masses. Therefore, the capillary structure of the heat transfer device of the present application has a higher permeability and better air permeability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Flow chart of the method for manufacturing a heat transfer device according to the first embodiment of the present application.

[0018] Figure 2 FIG. 1 is a schematic diagram of a first sintering step of the heat transfer device manufacturing method of the first embodiment of the present application.

[0019] Figure 3 FIG. 1 is a schematic diagram of a sintered mass in the heat transfer device of the first embodiment of the present application.

[0020] Figure 4Schematic diagram of the heat transfer device and its manufacturing method of the first embodiment of the present application and its secondary sintering step.

[0021] Figure 5 FIG. 1 is a schematic diagram of a capillary structure in the heat transfer device of the first embodiment of the present application.

[0022] Figure 6 to Figure 7 FIG. 1 is a schematic diagram of a heat transfer device according to the first embodiment of the present application.

[0023] Figures 8 to 10 FIG. 1 is a schematic diagram of a heat transfer device according to a second embodiment of the present application.

[0024] Description of reference numerals:

[0025] 100a: capillary structure;

[0026] 100: metal powder;

[0027] 101: first pore;

[0028] 102: second pore;

[0029] 110: sintered agglomerate;

[0030] 200: heat conductive housing;

[0031] 210: evaporation end;

[0032] 220: condensation end;

[0033] 230: evaporation surface;

[0034] 201: closed chamber;

[0035] 300: Working fluid. DETAILED DESCRIPTION

[0036] See also Figure 1 One embodiment of the present application provides a method for manufacturing a heat transfer device, which includes the following steps.

[0037] See also Figure 1 and Figure 2 First, in a primary sintering step a, metal powder 100 is provided. In this embodiment, the metal powder 100 is copper powder or aluminum powder. In this step, the metal powder 100 is sintered once to form a plurality of sintered agglomerates 110. Figure 3 In each sintered agglomerate 110 , there are gaps between particles of the agglomerated metal powder 100 , and the aforementioned gaps form a plurality of first pores 101 within the sintered agglomerate 110 .

[0038] See also Figure 1 and Figure 4, following step a, in the secondary sintering step b, a heat-conducting outer shell 200 is provided. In this embodiment, the heat-conducting outer shell 200 is made of copper or aluminum. In this embodiment, the heat transfer device is a heat pipe, so the heat-conducting outer shell 200 is in a tubular shape, but the present application is not limited thereto. In this step, the plurality of sintered masses 110 are subjected to secondary sintering to form a capillary structure 100a, and the capillary structure 100a is sintered and bonded to the heat-conducting outer shell 200. Figure 5 A plurality of second pores 102 are formed between the plurality of sintered masses 110 in the capillary structure 100a, and each first pore 101 in the capillary structure 100a is smaller than each second pore 102. Figure 6 and Figure 7 In this embodiment, the capillary structure 100a is configured to extend along the longitudinal direction of the heat-conducting housing 200 in accordance with the predetermined return path of the heat pipe. The sintered mass 110 covers at least a portion of the inner wall of the heat-conducting housing 200, that is, the capillary structure 100a covers at least a portion of the inner wall of the heat-conducting housing 200.

[0039] See also Figure 1 and Figure 7 , following step b, in step c, the heat-conducting housing 200 is filled with a working fluid 300, which is a fluid with a low boiling point and is in liquid state at room temperature. The working fluid 300 can be water, alcohol, or a refrigerant, etc., but the present application is not limited thereto. Following step c, in step d, the heat-conducting housing 200 is sealed to form a closed chamber 201 in the heat-conducting housing 200, so that the capillary structure 100a and the working fluid 300 are both located in the closed chamber 201.

[0040] See also Figure 8 and Fig. 9 The heat transfer device may be a temperature equalizer. The heat conductive housing 200 is a hollow flat plate. In the secondary sintering step b, the capillary structure 100a is arranged in the closed chamber 201 corresponding to one side of the heat conductive housing 200 in accordance with the predetermined return path of the heat pipe.

[0041] See also Figures 5 to 7 In the first embodiment of the present application, a heat transfer device is provided, which is manufactured by the above manufacturing method. In this embodiment, the heat transfer device is a heat pipe, which includes a heat conductive shell 200, a capillary structure 100a and a working fluid 300.

[0042] The heat-conducting housing 200 has a closed chamber 201 . In this embodiment, the heat-conducting housing 200 is made of copper or aluminum and is in a tubular shape.

[0043] The capillary structure 100a is disposed in the closed chamber 201. In this embodiment, each sintered mass 110 is formed by sintering copper powder or aluminum powder, and the capillary structure 100a is disposed along the longitudinal extension of the heat-conducting housing 200. The capillary structure 100a includes a plurality of sintered masses 110, and the plurality of sintered masses 110 cover at least a portion of the inner wall of the heat-conducting housing 200. Each sintered mass 110 is formed by sintering metal powder 100 and each sintered mass 110 has a plurality of first pores 101 therein, and a plurality of second pores 102 are formed between the plurality of sintered masses 110, wherein each first pore 101 is smaller than each second pore 102. The working fluid 300 is accommodated in the closed chamber 201, and the working fluid 300 is a fluid with a low boiling point and is in liquid state at room temperature. The working fluid 300 may be water, alcohol, or a refrigerant, etc., but the present application is not limited thereto.

[0044] The working fluid 300 can be adsorbed in the capillary structure 100a. When the evaporation end 210 of the heat-conducting housing 200 is heated, the working fluid 300 at the evaporation end 210 is vaporized, and the gaseous working fluid 300 flows along the longitudinal direction of the heat-conducting housing 200 in the closed chamber 201 to the condensation end 220 of the heat-conducting housing 200. After the gaseous working fluid 300 is condensed at the condensation end 220 of the heat-conducting housing 200, it is adsorbed by the capillary structure 100a and flows back to the evaporation end 210 along the capillary structure 100a.

[0045] The manufacturing method of the heat transfer device of the present application has a secondary sintering step. First, a certain amount of solid metal powder 100 is sintered into a sintered mass 110. Then, a certain amount of sintered mass 110 is sintered on the inner wall of the heat conductive shell 200 to form a capillary structure 100a in the heat transfer device. The metal powder 100 is densely stacked and the gaps between the sintered mass 110 are relatively large. In other words, the first pores 101 between the particles of the metal powder 100 are smaller than the second pores 102 between the sintered mass 110. Therefore, the capillary structure 100a of the heat transfer device of the present application has a higher permeability and better air permeability.

[0046] See also Figures 8 to 10 In the second embodiment of the present application, another heat transfer device is provided, which is manufactured by the above manufacturing method. In this embodiment, the heat transfer device is a vapor chamber, which includes a heat conductive housing 200, a capillary structure 100a and a working fluid 300.

[0047] The heat-conducting housing 200 has a closed chamber 201. The heat-conducting housing 200 in this embodiment is made of copper or aluminum. The heat-conducting housing 200 is a hollow flat plate, and one side of the heat-conducting housing 200 is an evaporation surface 230. The capillary structure 100a is arranged in the closed chamber 201 corresponding to the evaporation surface 230 of the heat-conducting housing 200. The capillary structure 100a includes a plurality of sintered agglomerates 110, and the plurality of sintered agglomerates 110 cover at least a portion of the inner wall of the heat-conducting housing 200. Each sintered agglomerate 110 is formed by sintering metal powder 100 and each sintered agglomerate 110 has a plurality of first pores 101 therein, and a plurality of second pores 102 are formed between the plurality of sintered agglomerates 110, wherein each first pore 101 is smaller than each second pore 102. The working fluid 300 is accommodated in the closed chamber 201, and the working fluid 300 is a low-boiling-point fluid and is in liquid state at room temperature. The working fluid 300 may be water, alcohol, or a refrigerant, etc., but the present application is not limited thereto.

[0048] In this embodiment, when the heat transfer device is in use, the working fluid 300 can be adsorbed in the capillary structure 100a. When the evaporation surface 230 of the heat-conducting housing 200 is heated, the working fluid 300 in the capillary structure 100a is vaporized, and the gaseous working fluid 300 diffuses in the closed chamber 201. The gaseous working fluid 300 leaves the evaporation surface 230, condenses, and is then adsorbed by the capillary structure 100a and flows back to the evaporation surface 230 along the capillary structure 100a.

[0049] The above description is only a preferred embodiment of the present application and is not intended to limit the patent scope of the present application. Other equivalent changes that apply the patent spirit of the present application should all fall within the patent scope of the present application.

Claims

1. A heat transfer device, characterized in that: Include: a thermally conductive housing having an enclosed chamber; A capillary structure is disposed in the closed chamber, the capillary structure comprises a plurality of sintered agglomerates, the plurality of sintered agglomerates cover at least a portion of the inner wall of the heat-conductive housing, each of the sintered agglomerates is formed by sintering metal powder and each of the sintered agglomerates has a plurality of first pores therein, a plurality of second pores are formed between the plurality of sintered agglomerates, wherein each of the first pores is smaller than each of the second pores; and The working fluid is contained in the closed chamber.

2. The heat transfer device as claimed in claim 1, wherein: Each of the sintered agglomerates is formed by sintering copper powder or aluminum powder.

3. The heat transfer device as claimed in claim 1, wherein: The heat-conducting shell is made of copper or aluminum.

4. The heat transfer device as claimed in claim 1, wherein: The heat-conducting housing is in a tubular shape.

5. The heat transfer device as claimed in claim 4, wherein: The capillary structure is configured along the longitudinal extension of the heat-conducting housing.

6. The heat transfer device as claimed in claim 1, wherein: The heat-conducting shell is in the shape of a hollow flat plate.

7. The heat transfer device as claimed in claim 6, wherein: The capillary structure is disposed in the closed chamber corresponding to one side of the heat-conducting housing.

8. A method for manufacturing a heat transfer device, characterized in that: Include: a) providing metal powder, and sintering the metal powder once to form a plurality of sintered agglomerates, wherein each of the sintered agglomerates has a plurality of first pores; b) providing a heat-conducting outer shell, performing secondary sintering on the plurality of sintered lumps to form a capillary structure and combining the capillary structure with the heat-conducting outer shell, wherein the plurality of sintered lumps cover at least a portion of an inner wall of the heat-conducting outer shell, a plurality of second pores are formed between the plurality of sintered lumps, and each of the first pores is smaller than each of the second pores; c) filling the heat-conducting housing with a working fluid; and d) sealing the heat-conducting housing to form a closed chamber in the heat-conducting housing, so that the capillary structure and the working fluid are located in the closed chamber.

9. The method for manufacturing a heat transfer device as claimed in claim 8, wherein: The metal powder is copper powder or aluminum powder.

10. The method for manufacturing a heat transfer device as claimed in claim 8, wherein: The heat-conducting shell is made of copper or aluminum.

11. The method for manufacturing a heat transfer device as claimed in claim 8, wherein: The heat-conducting outer shell is tubular, and in step b, the capillary structure is arranged along the longitudinal extension of the heat-conducting outer shell.

12. The method for manufacturing a heat transfer device as claimed in claim 8, wherein: The heat-conducting shell is in the shape of a hollow flat plate, and in step b, the capillary structure is arranged in the closed chamber corresponding to one side of the heat-conducting shell.

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