JP6597896B2 - Heat pipe manufacturing method - Google Patents

Description

The present invention also relates to the production how of the heat pipe.

The heat pipe is used for cooling a CPU mounted on an electronic device such as a personal computer. The heat pipe is a sealed metal body in which a non-condensable fluid is degassed and an appropriate amount of hydraulic fluid is enclosed. The hydraulic fluid enclosed in the container evaporates by being heated from the outside of the container in the evaporating unit, and is condensed by being cooled in the condensing unit when the vapor is cooled, and transports heat as latent heat. Since heat is transported as latent heat, heat can be transported even with a small temperature difference between the evaporation section and the condensation section.

In the container, it is necessary to return the working fluid condensed in the condensing part to the evaporation part. When the evaporating part is located above the condensing part, or when the evaporating part and the condensing part are located horizontally, the surface tension of the working fluid is used for the reflux of the working fluid. Therefore, a porous wick structure is required inside the container.

As the wick structure, a linear body in which a large number of fine wires are bundled, a mesh body such as a mesh, and a sintered body obtained by sintering metal powder such as copper powder are used. Among these, it is known that those using a sintered body of metal powder can obtain a high surface tension (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2015-135211

Usually, a heat pipe is bent according to the shape of an electronic device or the like. However, since the wick structure made of a sintered metal powder is hard and brittle, bending the heat pipe after forming the wick structure causes the wick structure to peel off from the inner wall of the container. Problems arise.

The present invention has been made to solve the above problems, and a method for manufacturing a heat pipe in which a wick structure is disposed on the inner wall of a bent portion of a container without peeling from the inner wall of the container during bending, and An object of the present invention is to provide a heat pipe manufactured by the method.

The manufacturing method of the heat pipe of the present invention includes a step of arranging a metal material containing Sn or Sn alloy as a first metal and a Cu alloy as a second metal so as to be in contact with an inner wall of a tubular container, and the container By heating the metal material in the metal material at a temperature lower than the melting point of the first metal, the Sn in the first metal contained in the metal material remains, and the first metal contained in the metal material remains. A step of reacting a part of the second metal with a part of the second metal to form an intermetallic compound, and fixing the metal material to the inner wall of the container by the intermetallic compound; and the container to which the metal material is fixed The step of bending the metal material and the unreacted contained in the metal material by heating the metal material in the container at a temperature equal to or higher than the melting point of the first metal after the bending process. The above first gold And the a second is reacted with metal, characterized in that it comprises a step of forming a wick structure porous consisting of intermetallic compound.

In the heat pipe manufacturing method of the present invention, an intermetallic compound of Sn or Sn alloy as the first metal and Cu alloy as the second metal having a higher melting point than the first metal is used as the wick structure. When the first metal (for example, Sn) and the second metal (for example, Cu—Ni alloy) are heated, the first metal melts when the temperature reaches the melting point of the first metal or higher. When the heating is further continued, the first metal and the second metal react to produce an intermetallic compound (for example, (Cu, Ni) ₆ Sn ₅ ). Since voids (pores) are generated when the intermetallic compound part is formed, the intermetallic compound becomes porous suitable for the wick structure.

However, since the wick structure made of the intermetallic compound is hard and brittle, if the heat pipe after forming the wick structure is subjected to bending, the wick structure cannot withstand deformation during bending. As a result, a crack or the like occurs in the wick structure, causing a problem that the wick structure peels off from the inner wall of the container.

Therefore, the heat pipe manufacturing method of the present invention is characterized in that heating for generating an intermetallic compound is performed before and after bending. First, before bending, the metal material is heated at a temperature lower than the melting point of the first metal (hereinafter also referred to as temporary heating). Since the first metal is not melted by this heating, Sn in the first metal contained in the metal material remains after the heating, but a part of the first metal and a part of the second metal contained in the metal material. React with each other by solid phase diffusion to produce an intermetallic compound. As a result, the metal material is fixed to the inner wall of the container by the intermetallic compound.

As described above, by heating the metal material at a temperature lower than the melting point of the first metal, it is possible to leave Sn having ductility in the first metal, and thus, after heating, a hard and brittle state like an intermetallic compound Can be prevented. Therefore, even if bending is performed on the container after heating, the metal material in the container is not cracked, and the shape of the metal material can be maintained without the metal material peeling off from the inner wall of the container. .

Further, after bending, the metal material is heated at a temperature equal to or higher than the melting point of the first metal (hereinafter also referred to as main heating). Since the first metal is melted by this heating, the unreacted first metal and the second metal react to generate an intermetallic compound. As a result, a wick structure made of an intermetallic compound is formed. By the above, the heat pipe by which the wick structure which consists of an intermetallic compound is arrange | positioned can be manufactured on the inner wall of the bending part of a container.

In the heat pipe manufacturing method of the present invention, the second metal is preferably a Cu-Ni alloy. The content of Ni in the Cu—Ni alloy is preferably 5% by weight or more and 15% by weight or less.
Cu-Ni alloys can react rapidly with Sn or Sn alloys to form intermetallic compounds. In particular, when the content of Ni in the Cu—Ni alloy is 5 wt% or more and 15 wt% or less, an intermetallic compound is reliably formed.

In the method for manufacturing a heat pipe of the present invention, the Cu—Ni alloy may be a Cu—Ni—M alloy (M is Co or Fe). The total content of Ni and M in the Cu-Ni-M alloy is preferably 3 wt% or more and 10 wt% or less.
Even when the Cu-Ni alloy contains Co or Fe, it can react rapidly with Sn or Sn alloy to form an intermetallic compound. When Co or Fe is M, an intermetallic compound is reliably formed when the total content of Ni and M in the Cu-Ni-M alloy is 3 wt% or more and 10 wt% or less.

In the method for manufacturing a heat pipe of the present invention, the Sn content in the first metal is preferably 90% by weight or more.
When the content of Sn in the first metal is 90% by weight or more, an intermetallic compound is reliably formed.

In the heat pipe manufacturing method of the present invention, the ratio of the weight of the first metal to the total weight of the first metal and the second metal in the metal material is preferably 20% or more and 60% or less.
When the ratio of the weight of the first metal in the metal material is 20% or more and 60% or less, Sn in the first metal can be left in the step of heating the metal material at a temperature lower than the melting point of the first metal. In the step of heating the metal material at a temperature equal to or higher than the melting point of the first metal, Sn in the first metal can be prevented from remaining.

In the method for manufacturing a heat pipe according to the present invention, in the step of heating the metal material at a temperature equal to or higher than the melting point of the first metal, a state in which a bonding material is interposed between the container to which the metal material is fixed and another component. The other parts may be joined to the outer wall of the container by heating at.
In this case, since the formation of the wick structure in the container and the joining of other parts to the container can be performed simultaneously by one heating, the working efficiency can be improved.

As described above, the heat pipe manufacturing method of the present invention manufactures a heat pipe in which a wick structure made of an intermetallic compound of a first metal and a second metal is arranged on the inner wall of a bent portion of a container. Can do. Such a heat pipe is also one aspect of the present invention.

That is, the heat pipe of the present invention is a heat pipe comprising a tubular container and a porous wick structure disposed so as to contact the inner wall of the container, wherein the wick structure is a first metal. It is made of an intermetallic compound of Sn or Sn alloy as a second metal and Cu alloy as a second metal, the container has a bent portion, and the wick structure is arranged on the inner wall of the bent portion. To do.

According to the present invention, there is provided a heat pipe manufacturing method in which a wick structure is disposed on the inner wall of a bent portion of a container without peeling from the inner wall of the container during bending, and a heat pipe manufactured by the method can do.

Drawing 1A-Drawing 1D are explanatory views showing typically an example of a manufacturing method of a heat pipe concerning a 1st embodiment of the present invention. 2A to 2E are explanatory views schematically showing an example of a heat pipe manufacturing method according to the second embodiment of the present invention. FIG. 3 is a perspective view schematically showing a filling method of the metal powder. FIG. 4 is a cross-sectional view schematically showing a bending test method. Fig.5 (a) and FIG.5 (b) are the photographs after the bending test of Example 1-1. FIG. 6A and FIG. 6B are photographs after the bending test of Comparative Example 1-1.

Hereinafter, the embodiment of the manufacturing method of the heat pipe of the present invention is described.
However, the present invention is not limited to the following configurations, and can be applied with appropriate modifications without departing from the scope of the present invention. In addition, what combined 2 or more desirable structures of each embodiment described below is also this invention.

Each embodiment shown below is an illustration, and it cannot be overemphasized that a partial substitution or combination of composition shown in a different embodiment is possible. In the second and subsequent embodiments, description of matters common to the first embodiment will be omitted, and only different points will be described. In particular, the same operational effects by the same configuration will not be sequentially described for each embodiment.

Hereinafter, the manufacturing method of the heat pipe which concerns on 1st Embodiment of this invention is demonstrated.
Drawing 1A-Drawing 1D are explanatory views showing typically an example of a manufacturing method of a heat pipe concerning a 1st embodiment of the present invention. 1A to 1D, a perspective view is shown on the left side, and a cross-sectional view of a portion indicated by a double arrow in the perspective view is shown on the right side.

First, as shown in FIG. 1A, the metal material 10 including the first metal 11 and the second metal 12 is disposed so as to contact the inner wall of the tubular container 20. In FIG. 1A, a mixed powder of a powder of the first metal 11 and a powder of the second metal 12 is arranged in the container 20 as the metal material 10.

The container is preferably made of a material having high thermal conductivity because heat needs to be transferred inside and outside. As a material for the container, for example, a metal such as copper or aluminum can be used. In addition, since heat pipes need to have heat resistance and mechanical strength that can withstand internal vapor pressure and external force, for example, stainless steel, copper alloy, carbon steel, etc. may be used as the container material. it can. The shape of the container is not particularly limited, and may be a cylinder other than a cylinder. Further, the shape of the inner wall of the container is not particularly limited, and a capillary structure such as a groove may be provided on the inner wall.

The first metal is Sn or Sn alloy, for example, Sn alone, Cu, Ni, Ag, Au, Sb, Zn, Bi, In, Ge, Al, Co, Mn, Fe, Cr, Mg, Mn An alloy containing Sn and at least one selected from the group consisting of Pd, Si, Sr, Te, and P is given. For example, Sn, Sn-3Ag-0.5Cu, Sn-3.5Ag, Sn-5Ag, Sn-0.7Cu, Sn-0.75Cu, Sn-58Bi, Sn-0.7Cu-0.05Ni, Sn- 5Sb, Sn-2Ag-0.5Cu-2Bi, Sn-57Bi-1Ag, Sn-3.5Ag-0.5Bi-8In, Sn-9Zn, or Sn-8Zn-3Bi.
In the above notation, for example, “Sn-3Ag-0.5Cu” indicates an alloy containing 3% by weight of Ag, 0.5% by weight of Cu, and the balance being Sn.

The content of Sn in the first metal is preferably 90% by weight or more, more preferably 91% by weight or more, and further preferably 95% by weight or more. When the content of Sn in the first metal is in the above range, an intermetallic compound is reliably formed.

A 2nd metal is Cu alloy, for example, Cu-Ni alloy, Cu-Mn alloy, Cu-Al alloy, or Cu-Cr alloy is mentioned. The second metal may contain Mn and Ni at the same time, such as Cu—Mn—Ni, and may contain a third component such as P.

The second metal is preferably a Cu—Ni alloy. Cu-Ni alloys can react rapidly with Sn or Sn alloys to form intermetallic compounds.
When the second metal is a Cu—Ni alloy, the content of Ni in the Cu—Ni alloy is preferably 5% by weight to 15% by weight, and more preferably 8% by weight to 12% by weight. preferable. When the content of Ni in the Cu-Ni alloy is in the above range, an intermetallic compound is reliably formed. Examples of the Cu—Ni alloy include Cu-5Ni, Cu-10Ni, and Cu-15Ni.
In the above notation, for example, “Cu-5Ni” indicates an alloy containing 5% by weight of Ni and the balance being Cu.

The Cu—Ni alloy may include a third component such as a Cu—Ni—Co alloy, a Cu—Ni—Fe alloy, or the like. When the Cu-Ni alloy is a Cu-Ni-M alloy (M is Co or Fe), the total content of Ni and M in the Cu-Ni-M alloy is 3 wt% or more and 10 wt% or less. Is preferable, and it is more preferable that it is 5 to 10 weight%. In particular, when the Cu—Ni alloy is a Cu—Ni—Co alloy, the total content of Ni and Co in the Cu—Ni—Co alloy is preferably 5 wt% or more and 10 wt% or less.

In the metal material, the ratio of the weight of the first metal to the total weight of the first metal and the second metal is preferably 20% or more and 60% or less, and more preferably 20% or more and 40% or less.
Since Sn in the first metal has ductility, the more the Sn, the easier the metal material bends. However, if Sn remains in the wick structure after heating, the heat transport property is said to deteriorate. When the ratio of the weight of the first metal in the metal material is within the above range, Sn in the first metal can be left in the step of heating the metal material at a temperature lower than the melting point of the first metal. In the step of heating the metal material at a temperature equal to or higher than the melting point of the metal, Sn in the first metal can be prevented from remaining.

When arranging the metal material in the container, the metal material is arranged so that a gap is formed in the container after the main heating (see FIG. 1D).
As shown in FIG. 1A, when using a mixed powder of a first metal powder and a second metal powder as a metal material, as a method of arranging the metal material in the container, for example, a core rod is inserted into the container. And a method of filling the mixed powder in the space between the inner wall of the container and the core rod. As will be described later, since the metal material is fixed to the inner wall of the container after the step of heating the metal material at a temperature lower than the melting point of the first metal, the core rod is pulled out from the container before the bending process. And voids can be formed in the container.

As a material for the core rod, for example, stainless steel, alumina or the like can be used. Moreover, the core rod which consists of a heat generating body may be sufficient like the ceramic tube (For example, the alumina tube which incorporated the nichrome wire) which incorporated the heat ray.

The shape of the core rod is not particularly limited, but is preferably a cylindrical shape. The core rod may have a cutout portion along the long axis direction, or may have a shape that can be divided. Further, the shape of the core rod may be a truncated cone shape. The length of the core rod is not particularly limited, but is preferably the same as the container length or longer than the container.

In FIG. 1A, a mixed powder of the first metal powder and the second metal powder is used as the metal material, but the form of the metal material is not particularly limited, and powder, foil, mesh sheet, wire, paste, etc. And a combination thereof may be used. When arrange | positioning these metal materials in a container, the above-mentioned core rod may be used and it is not necessary to use it.

Next, the metal material in the container is heated at a temperature lower than the melting point of the first metal (temporary heating). Since the first metal is not melted by this heating, Sn in the first metal contained in the metal material remains after the heating, but as shown in FIG. 1B, the first metal 11 contained in the metal material 10 A part of the second metal 12 reacts with the solid phase diffusion to generate an intermetallic compound 13. As a result, the metal material 10 is fixed to the inner wall of the container 20 by the intermetallic compound 13.

The heating temperature is not particularly limited as long as it is a temperature lower than the melting point of the first metal, but is preferably 150 ° C. or higher and 230 ° C. or lower, and more preferably 200 ° C. or higher and 230 ° C. or lower. Further, when the first metal is an Sn alloy, it is preferable to heat at a temperature lower than the solidus temperature of the first metal. The heating time is preferably 5 minutes or more and 35 minutes or less, and more preferably 10 minutes or more and 30 minutes or less.

Subsequently, as shown in FIG. 1C, the container 20 to which the metal material 10 is fixed is bent. Thereby, the bent part 21 is formed in the container 20.
Since Sn having ductility remains in the first metal, even if the container to which the metal material is fixed is bent, the metal material in the container is not cracked, and the metal material from the inner wall of the container. The shape of the metal material can be maintained without peeling off.

In this specification, the bending process includes a twisting process. The shape, direction, etc. of the bent part formed by bending are not particularly limited. Moreover, you may perform a bending process with respect to two or more places of a container.

The container to which the metal material is fixed may be flattened after being bent or before being bent.

After bending, the metal material in the container is heated at a temperature equal to or higher than the melting point of the first metal (main heating). Since the first metal is melted by this heating, the unreacted first metal and the second metal contained in the metal material react to generate an intermetallic compound. As the intermetallic compound is generated, voids (pores) are formed in the intermetallic compound, so that the intermetallic compound is porous. As a result, as shown in FIG. 1D, a porous wick structure 14 made of an intermetallic compound is formed. The wick structure 14 is fixed in the container 20 as the molten intermetallic compound hardens.

As described above, since the intermetallic compound constituting the wick structure is porous, the working fluid can be moved by capillary action. On the other hand, the void in the container functions as a steam flow path.

Although heating temperature will not be specifically limited if it is the temperature more than melting | fusing point of a 1st metal, 250 to 350 degreeC is preferable. The heating time is preferably 5 minutes or more and 60 minutes or less.

The intermetallic compound in the metal material or the wick structure can be easily confirmed by cross-sectional observation using a metal microscope. Specifically, intermetallic compounds such as (Cu, Ni) ₆ Sn ₅ are confirmed by performing composition analysis by energy dispersive X-ray analysis (EDX) and the like and crystal structure analysis by microscopic X-ray diffraction and the like. can do.

Thereafter, if necessary, non-condensable gas such as air existing inside the container is degassed, and the working liquid is sealed in the container. As the hydraulic fluid, water, ethanol, methanol, naphthalene, benzene, alternative chlorofluorocarbon, ammonia or the like can be used. In addition, for degassing non-condensable gas, a vacuum degassing method or a method of injecting an excess amount of hydraulic fluid in advance and driving out the non-condensable gas by boiling the hydraulic fluid by heating the container Etc. are used.

By the above, the heat pipe by which the wick structure which consists of an intermetallic compound is arrange | positioned can be manufactured on the inner wall of the bending part of a container.

In the manufactured heat pipe, it is sufficient that the wick structure is disposed at least on the inner wall of the bent portion of the container, but it is preferable that the wick structure is also disposed on the inner wall other than the bent portion.

Hereinafter, the manufacturing method of the heat pipe which concerns on 2nd Embodiment of this invention is demonstrated.
2A to 2E are explanatory views schematically showing an example of a heat pipe manufacturing method according to the second embodiment of the present invention. 2A to 2C, as in FIGS. 1A to 1C, a perspective view is shown on the left side, and a cross-sectional view of a portion indicated by a double-headed arrow in the perspective view is shown on the right side. 2D and 2E, a perspective view is shown on the left side, a cross-sectional view of the bent portion of the container is shown on the right side, and a cross-sectional view of the tip of the container is shown in the center.

First, as illustrated in FIG. 2A, the metal material 10 including the first metal 11 and the second metal 12 is disposed so as to contact the inner wall of the tubular container 20. Next, by heating the metal material in the container at a temperature lower than the melting point of the first metal (preliminary heating), as shown in FIG. 2B, the Sn in the first metal 11 remains, and the metal material 10 A part of the first metal 11 and a part of the second metal 12 included are reacted to form an intermetallic compound 13, and the metal material 10 is fixed to the inner wall of the container 20 by the intermetallic compound 13. Subsequently, as shown in FIG. 2C, a bending portion 21 is formed in the container 20 by bending the container 20 to which the metal material 10 is fixed.

2A to 2C are the same as the steps of FIGS. 1A to 1C, and detailed description of each step is omitted.

After bending, as shown in FIG. 2D, another component 30 such as a heat sink is placed on the tip of the container 20 with a bonding material 40 such as a solder paste interposed therebetween.

The bonding material preferably contains Sn or Sn alloy as the first metal. The first metal contained in the bonding material may be the same as or different from the first metal contained in the metal material, but it must have a melting point equal to or lower than the melting point of the first metal contained in the metal material. There is. The bonding material may further include a Cu alloy that is the second metal. The second metal contained in the bonding material may be the same as or different from the second metal contained in the metal material. The bonding material may further contain a flux in addition to the metal material such as the first metal.

The metal material is heated at a temperature equal to or higher than the melting point of the first metal with the bonding material interposed between the container and another component (main heating). Thereby, since the 1st metal in a metal material fuses, the unreacted 1st metal and 2nd metal which are contained in a metal material react like 1st Embodiment, and an intermetallic compound produces | generates. As a result, as shown in FIG. 2E, a porous wick structure 14 made of an intermetallic compound is formed in the container 20. The wick structure 14 is fixed in the container 20 as the molten intermetallic compound hardens. Further, since the first metal in the bonding material is also melted, when the molten first metal is solidified, the other component 30 is bonded to the outer wall of the container 20 by the bonding member 41.

The heating temperature and heating time are the same as in the first embodiment. In 2nd Embodiment, it is preferable to join another component to the outer wall of a container by a reflow system, and specifically, it is preferable to heat using a reflow furnace or a belt furnace.

As another part joined to the outer wall of a container, a heat sink etc. are mentioned, for example. The position of the container to which other parts are joined is not limited to the tip, and may be joined to any position. Two or more parts may be joined to the outer wall of the container.

In FIGS. 2A to 2E, other parts are placed on the container after bending, but other parts may be placed on the container before bending.

Thereafter, if necessary, non-condensable gas such as air existing inside the container is degassed, and the working liquid is sealed in the container.

As described above, it is possible to manufacture a heat pipe in which the wick structure is disposed on the inner wall of the bent portion of the container and other components are joined to the outer wall of the container.

Hereinafter, the Example which disclosed the manufacturing method of the heat pipe of the present invention more concretely is shown. In addition, this invention is not limited only to these Examples.

(Example 1-1 to Example 1-4, Comparative Example 1-1, and Comparative Example 1-2)
(1-1) Filling of Metal Powder FIG. 3 is a perspective view schematically showing a filling method of the metal powder.
First, a silicone rubber plate 51 (50 mm × 25 mm × 0.5 mmt, opening 40 mm × 20 mm) having an opening was placed on a copper plate 50 (copper-free copper, 50 mm × 25 mm × 0.2 mmt).
Sn powder 61 (first metal) having an average particle diameter of 50 μm and Cu alloy powder 62 (second metal) having an average particle diameter of 60 μm were mixed at a predetermined weight ratio and filled in the opening of the silicone rubber plate 51. Table 1 shows the components of the Cu alloy powder and the ratio of the weight of Sn to the total weight of Sn and Cu alloy.

(1-2) Heating of metal powder About the metal powder with which the opening part on the copper plate was filled, it heated on the heating conditions shown in Table 1 in nitrogen atmosphere using oven. The heating conditions of Example 1-1 to Example 1-4 and Comparative Example 1-2 correspond to temporary heating, and the heating condition of Comparative Example 1-1 corresponds to main heating. By this heating, a metal film was formed on the copper plate. After heating, the silicone rubber plate was removed from the copper plate.

The cross section of the metal film was observed using a metal microscope, and the main components of the metal film after heating were identified. Table 1 shows main components of the metal film after heating. In Table 1, IMC means an intermetallic compound.

(1-3) Bending Test FIG. 4 is a cross-sectional view schematically showing a bending test method.
The copper plate 50 on which the metal film 63 was formed was wound around a round bar 52 (SUS304). As shown in FIG. 4, the metal film 63 was wound outward.
The diameter of the round bar 52 was changed in the order of 60 mmφ, 50 mmφ, and 40 mmφ, and the case where the metal film was not peeled at the time of winding was judged as ◯ (passed), and the case where the metal film was peeled was judged as x (failed). In addition, the presence or absence of peeling was confirmed visually.

Table 1 shows the results of the bending test. Table 1 shows the minimum diameter of a round bar that could be bent without peeling off the metal film. When the diameter of the round bar was 60 mmφ, it was indicated as x.
5 (a) and 5 (b) are photographs after the bending test of Example 1-1, and FIGS. 6 (a) and 6 (b) are after the bending test of Comparative Example 1-1. Each photo is shown. 5 (a) and 5 (b), the diameter of the round bar is 60 mmφ.

In the "judgment" column of Table 1, in a bending test, a round bar having a diameter of up to 40 mmφ was accepted, ◯, 50 mmφ or 60 mmφ passed, a round bar having a diameter of 60 mmφ, and an unacceptable x. .

From Table 1, in Examples 1-1 to 1-4, by heating at a temperature lower than 232 ° C., which is the melting point of Sn, Sn remains and an intermetallic compound is formed. The film did not peel. In particular, in Example 1-1 and Example 1-2 in which the heating temperature was 200 ° C. or higher, the metal film did not peel even when the diameter of the round bar was 40 mmφ.

On the other hand, in Comparative Example 1-1 heated at a temperature equal to or higher than the melting point of Sn, an intermetallic compound was formed after heating, but Sn did not remain, and the metal film peeled in the bending test. Further, in Comparative Example 1-2 in which the heating temperature was 120 ° C., no intermetallic compound was formed after heating, and the metal film was not fixed to the copper plate, so that the metal film was peeled off in the bending test.

(Example 2-1 to Example 2-10, Comparative Example 2-1 and Comparative Example 2-2)
(2-1) Filling of metal powder As shown in Table 2, the ratio of the weight of Sn to the total weight of the components of the Cu alloy powder and Sn and the Cu alloy was changed.
As in (1-1) above, Sn powder (first metal) having an average particle diameter of 50 μm and Cu alloy powder (second metal) having an average particle diameter of 60 μm are mixed at a predetermined weight ratio, and the opening of the silicone rubber plate The part was filled. However, in Comparative Example 2-1, Cu powder was used instead of Cu alloy powder. Table 2 shows the components of the Cu alloy powder and the ratio of the weight of Sn to the total weight of Sn and Cu alloy.

(2-2) About the metal powder with which the opening part on a temporary heating copper plate was filled, it heated on 210 degreeC and the conditions for 10 minutes in nitrogen atmosphere using oven. By this heating, a metal film was formed on the copper plate. After heating, the silicone rubber plate was removed from the copper plate.

The cross section of the metal film was observed using a metal microscope, and the main components of the metal film after temporary heating were identified. Table 2 shows main components of the metal film after temporary heating. In Table 2, IMC means an intermetallic compound.

(2-3) Bending test The bending test was done with respect to the copper plate in which the metal film was formed by the method similar to said (1-3). Table 2 shows the results of the bending test.

(2-4) The sample after the main heating bending test was flattened with a roller, and then heated in a reflow oven under a nitrogen atmosphere at 260 ° C. for 5 minutes.

The cross section of the metal film was observed using a metal microscope, and the main components of the metal film after the main heating were identified. Table 2 shows main components of the metal film after the main heating.

(2-5) Evaluation of Residual Sn Rate About 10 mg of the metal film after the main heating was cut out, and the measurement was performed under the conditions of a measurement temperature of 30 ° C. to 350 ° C., a temperature increase rate of 5 ° C./min, an N ₂ atmosphere, and a reference Al ₂ O _3. Scanning calorimetry (DSC measurement) was performed. The amount of the remaining Sn component was quantified from the endothermic amount of the melting endothermic peak at the melting temperature of the Sn component of the obtained DSC chart, and the ratio of the Sn component to the entire metal component was evaluated as the remaining Sn rate. A case where the residual Sn ratio was 0% by volume was evaluated as ◎ (excellent), a case where it exceeded 0% by volume and less than 1% by volume was evaluated as ◯ (possible), and a case where it was 1% by volume or more was evaluated as × (not possible).
Table 2 shows the remaining Sn rate and determination results.

In the “determination” column of Table 2, in the bending test, the diameter of the round bar passed up to 40 mmφ, the remaining Sn ratio was ◎, the bending test was passed, and the remaining Sn ratio was ◎ or The ones with ◯ were ◯, the bending test was acceptable, the one with a residual Sn ratio of x was Δ, and the one with an unacceptable bending test regardless of the result of the residual Sn ratio was x. The same applies to the “determination” column in Table 3.

From Table 2, in Comparative Example 2-1, in which Cu powder was used as the second metal, no intermetallic compound was formed after temporary heating, and the metal film was peeled off in a bending test. Further, in Comparative Example 2-2 in which the ratio of the Sn weight to the total weight of Sn and the Cu alloy was 10%, Sn did not remain after temporary heating, and the metal film peeled in the bending test.

On the other hand, in Example 2-1 to Example 2-10 using Cu alloy powder, Sn remained after provisional heating and an intermetallic compound was formed, and the metal film did not peel in the bending test.

When a Cu-Ni alloy was used as the Cu alloy, the content of Ni in the Cu-Ni alloy was 10 wt% from the results of Example 2-2, Example 2-5, and Example 2-6. As a result, it was confirmed that the metal film did not peel even when the diameter of the round bar was 40 mmφ.

In addition, from the results of Example 2-1 to Example 2-4, the ratio of the Sn weight to the total weight of Sn and the Cu alloy is 20% or more and 60% or less. confirmed.

Further, from the results of Example 2-7 to Example 2-10, even when a Cu—Ni—Co alloy or a Cu—Ni—Fe alloy is used as the Cu alloy, as in the case of using the Cu—Ni alloy, In the bending test, it was confirmed that the metal film did not peel off. In particular, when a Cu—Ni—Co alloy is used as the Cu alloy, the diameter of the round bar is reduced by setting the total content of Ni and Co in the Cu—Ni—Co alloy to 5 wt% or more and 10 wt% or less. It was confirmed that even when the diameter was 40 mmφ, the metal film was not peeled off and the residual Sn ratio was lowered.

(Example 3-1 to Example 3-4)
(3-1) Filling of metal powder As shown in Table 3, Sn alloy powder was used as the first metal.
Similar to (1-1) above, Sn alloy powder (first metal) with an average particle diameter of 50 μm and Cu alloy powder (second metal) with an average particle diameter of 60 μm are mixed at a predetermined weight ratio, and the silicone rubber plate The opening was filled. Table 3 shows the composition of the Sn alloy powder and the solidus temperature, the composition of the Cu alloy powder, and the ratio of the Sn alloy weight to the total weight of the Sn alloy and the Cu alloy.

(3-2) About the metal powder with which the opening part on a temporary heating copper plate was filled, it heated in nitrogen atmosphere using oven. The heating conditions were 210 ° C. and 10 minutes in Example 3-1 to Example 3-3, and 190 ° C. and 10 minutes in Example 3-4. By this heating, a metal film was formed on the copper plate. After heating, the silicone rubber plate was removed from the copper plate.

The cross section of the metal film was observed using a metal microscope, and the main components of the metal film after temporary heating were identified. Table 3 shows main components of the metal film after temporary heating. In Table 3, IMC means an intermetallic compound.

(3-3) Bending test The bending test was done with respect to the copper plate in which the metal film was formed by the method similar to said (1-3). Table 3 shows the results of the bending test.

(3-4) The sample after the main heating bending test was flattened with a roller, and then heated in a reflow furnace at 260 ° C. for 5 minutes in a nitrogen atmosphere.

The cross section of the metal film was observed using a metal microscope, and the main components of the metal film after the main heating were identified. Table 3 shows main components of the metal film after the main heating.

(3-5) Evaluation of residual Sn ratio The residual Sn ratio was evaluated by the same method as in (2-5) above. Table 3 shows the remaining Sn rate and determination results.

From Table 3, when Sn alloy powder was used instead of Sn powder, the same result as that obtained when Sn powder was used was obtained.

DESCRIPTION OF SYMBOLS 10 Metal material 11 1st metal 12 2nd metal 13 Intermetallic compound 14 Wick structure 20 Container 21 Bending part 30 Other components 40 Joining material 41 Joining member 50 Copper plate 51 Silicone rubber plate 52 Round bar 61 Sn powder 62 Cu alloy powder 63 Metal film

Claims (8)

Disposing a metal material containing Sn or Sn alloy as the first metal and Cu alloy as the second metal so as to contact the inner wall of the tubular container;
The metal material in the container is heated at a temperature lower than the melting point of the first metal to leave Sn in the first metal contained in the metal material, and the first material contained in the metal material. Reacting a part of the metal with a part of the second metal to form an intermetallic compound, and fixing the metal material to the inner wall of the container by the intermetallic compound;
A step of bending the container to which the metal material is fixed;
After the bending process, the unreacted first metal and the second metal contained in the metal material are heated by heating the metal material in the container at a temperature equal to or higher than the melting point of the first metal. To form a porous wick structure made of an intermetallic compound,
A method of manufacturing a heat pipe, comprising: The method for manufacturing a heat pipe according to claim 1, wherein the second metal is a Cu—Ni alloy. The method for producing a heat pipe according to claim 2, wherein the content of Ni in the Cu-Ni alloy is 5 wt% or more and 15 wt% or less. The method for manufacturing a heat pipe according to claim 2, wherein the Cu-Ni alloy is a Cu-Ni-M alloy (M is Co or Fe). The method for manufacturing a heat pipe according to claim 4, wherein the total content of Ni and M in the Cu-Ni-M alloy is 3 wt% or more and 10 wt% or less. The method for producing a heat pipe according to any one of claims 1 to 5, wherein a content of Sn in the first metal is 90 wt% or more. The heat according to any one of claims 1 to 6, wherein a ratio of a weight of the first metal to a total weight of the first metal and the second metal in the metal material is 20% or more and 60% or less. Pipe manufacturing method. In the step of heating the metal material at a temperature equal to or higher than the melting point of the first metal, the other component is heated by heating the container to which the metal material is fixed and the other component with a bonding material interposed therebetween. The manufacturing method of the heat pipe of any one of Claims 1-7 which joins to the outer wall of the said container.

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