JP2018193584A - Copper porous body, copper porous composite member, manufacturing method of copper porous body and manufacturing method of copper porous composite member - Google Patents

Abstract

To provide a copper porous body having high porosity and sufficient strength, a copper porous composite member in which the copper porous body binds to a member body, a manufacturing method of the copper porous body and a manufacturing method of the copper porous composite member.SOLUTION: There is provided a copper porous body consisting of a sintered body of a plurality of copper fibers, and having a skeleton part of a three-dimensional network structure, in which the copper fibers forming the skeleton part consist of copper or copper alloy, diameter R is in a range from 0.01 mm or more to 1.0 mm or less, a ratio of length L and the diameter R, L/R is in a range from 4 or more to 200 or less, circularity of a cross section orthogonal to a length direction is 0.92 or more and porosity is in a range from 50% or more to 90% or less.SELECTED DRAWING: None

Description

  The present invention relates to a copper porous body made of copper or a copper alloy, a copper porous composite member obtained by bonding the copper porous body to a member body, a method for producing a copper porous body, and a copper porous composite. The present invention relates to a method for manufacturing a member.

The above-mentioned copper porous sintered body and copper porous composite member are used as, for example, electrodes and current collectors in various batteries, heat exchanger members such as heat pipes, silencers, filters, impact absorbing members, and the like.
For example, Patent Document 1 proposes a heat transfer member in which a copper porous body forming a three-dimensional network structure is integrally attached to a conductive metal member body.

  Here, in patent document 1, as a manufacturing method of the metal sintered compact (copper porous body) which makes a three-dimensional network structure, the three-dimensional network structure (for example, urethane foam, which consists of a material burned down by heating) Polyethylene foam, synthetic resin foam with continuous cells, natural fiber cloth, man-made fiber cloth, etc.). And a method of using a sheet-like molded body in which a metal powder is formed on a material (for example, pulp or wool fiber) that can form a three-dimensional network structure.

Here, as described in Patent Document 1, when a metal sintered body (copper porous sintered body) is formed using a metal powder, since the shrinkage rate during sintering is large, the conduction There is a problem in that it is difficult to obtain a copper porous sintered body that is not secured with a path, is excellent in conductivity and thermal conductivity, and has a high porosity.
Thus, for example, as shown in Patent Documents 2 and 3, a copper porous body using copper fibers made of copper or a copper alloy as a sintering raw material has been proposed.

Patent Document 2 discloses a method for obtaining a copper porous body by conducting energization heating of copper fibers under pressure.
Patent Document 3 discloses a method of obtaining a copper porous body by heating copper fibers to 800 ° C. in an air atmosphere and then heating to 450 ° C. in a hydrogen atmosphere.

Japanese Patent Laid-Open No. 08-145592 Japanese Patent No. 3735712 JP 2000-192107 A

By the way, in the above-mentioned copper porous body, high conductivity is required when used as a conductive member in combination with having a high porosity and an open cell structure. Further, when used as a heat exchange member, high thermal conductivity is required.
Here, in patent document 2, in order to fully join copper fibers, since it is necessary to perform electric sintering under pressure, there existed a problem that a porosity fell by pressurization. Moreover, since it is necessary to pressurize uniformly, there existed a problem that the shape of the shaping | molding die used at the time of sintering will be restrict | limited.
Furthermore, in Patent Document 3, since heating is performed in an air atmosphere, voids are generated when the oxygen concentration in the copper fiber is increased and heating is performed in a hydrogen atmosphere thereafter, and the conductivity and heat of the copper porous body are increased. There was a possibility that the conductivity was lowered.

  The present invention has been made in the background as described above, and has a high porosity and a sufficient conductivity and thermal conductivity, and the copper porous body is bonded to a member body. An object of the present invention is to provide a produced copper porous composite member, a method for producing a copper porous body, and a method for producing a copper porous composite member.

  In order to solve such problems and achieve the above-mentioned object, the copper porous body of the present invention comprises a sintered body of a plurality of copper fibers and has a three-dimensional network structure skeleton portion. The copper fiber forming the skeleton is made of copper or a copper alloy, the diameter R is in the range of 0.01 mm to 1.0 mm, and the ratio L / L of the length L to the diameter R is L / R is in the range of 4 or more and 200 or less, the circularity of the cross section perpendicular to the length direction is 0.92 or more, and the porosity is in the range of 50% or more and 90% or less. It is characterized by that.

According to the copper porous body having this configuration, the diameter R of the copper fiber forming the skeleton is in the range of 0.01 mm to 1.0 mm, and the ratio L / R of the length L to the diameter R is L / R. Is in the range of 4 or more and 200 or less, a sufficient gap is ensured between the copper fibers, and the porosity can be in the range of 50% or more and 90% or less.
Here, the diameter R is a value calculated on the basis of the cross-sectional area A of each fiber, and is defined by the following equation assuming a perfect circle regardless of the cross-sectional shape.
R = (A / π) ^1/2 × 2

And in this invention, the circularity of the cross section orthogonal to the length direction of the copper fiber which forms the said frame | skeleton part is prescribed | regulated. Here, the circularity C is expressed by the following equation, where A is the cross-sectional area of the copper fiber and Q is the circumferential length of the cross-section of the copper fiber.
Circularity C = (4πA) ^0.5 / Q
When the cross-sectional shape is a perfect circle, the circularity C is 1. When the cross-sectional shape is a polygon, a rectangle with a large aspect ratio, or the like, the circularity C is a smaller value in the range of 0 <C ≦ 1.

In the present invention, since the circularity of the cross section of the copper fiber forming the skeleton portion is 0.92 or more, when the copper fibers are laminated, the number of places where the copper fibers are in contact with each other is increased. A sufficient number of contact points between the copper fibers is ensured. In addition, since the cross-sectional shape approximates a circle and the cross-sectional shape variation is small, the contact area variation at each contact point is also small, so a uniform conduction path is formed inside the finally obtained copper porous body. It becomes possible to form, and it becomes possible to improve the electroconductivity of a copper porous material, and also to ensure a space | gap between copper fibers, and it becomes possible to make a porosity high.
Accordingly, it is possible to provide a copper porous body having a high porosity and sufficient conductivity. Further, it is possible to provide an excellent copper porous material in heat conduction using free electrons as carriers as well as electric conduction.

The copper porous composite member of the present invention is a copper porous composite member comprising a joined body of a member main body and a copper porous body having a three-dimensional network structure skeleton, wherein the copper porous body is the above-mentioned copper porous body. It is characterized by being a copper porous body.
According to the copper porous composite member having this configuration, since it is a joined body of a copper porous body and a member main body having high porosity and excellent conductivity and thermal conductivity, it has excellent characteristics. A porous composite member can be provided.

Here, in the copper porous composite member of the present invention, the joint surface of the member main body with the copper porous body is composed of copper or a copper alloy, and the joint portion between the copper porous body and the member main body. Is preferably a sintered layer.
In this case, since the joining portion between the copper porous body and the member main body is a sintered layer, the copper porous body and the member main body are firmly joined, and the copper porous composite Excellent conductivity and thermal conductivity can be obtained as a member.

  Moreover, the manufacturing method of the copper porous body of this invention is a manufacturing method of the copper porous body which consists of a sintered compact of a some copper fiber, and has the frame | skeleton part of a three-dimensional network structure, and the diameter R is 0.00. The ratio L / R between the length L and the diameter R is in the range of 4 to 200 and the circularity of the cross section is 0.92 or more. And a copper fiber laminating step for laminating the copper fibers, and a sintering step for sintering the plurality of laminated copper fibers.

  According to the method for producing a copper porous body having this configuration, the diameter R of the copper fiber is in the range of 0.01 mm or more and 1.0 mm or less, and the ratio L / R of the length L to the diameter R is 4 or more. Since the circularity of the cross section perpendicular to the length direction is 0.92 or more within the range of 200 or less, the number of contact points between the copper fibers will be secured, and the conductivity and thermal conductivity will be An excellent copper porous body can be obtained. Moreover, a space | gap can be ensured between copper fibers, and a copper porous body with a high porosity can be obtained.

  The method for producing a copper porous composite member of the present invention is a method for producing a copper porous composite member comprising a joined body of a member main body and a copper porous body having a three-dimensional network structure skeleton. It has the joining process which joins a copper porous body and the said member main body.

  According to the manufacturing method of the copper porous composite member having this configuration, the copper porous body manufactured by the above-described manufacturing method of the copper porous body is provided, and the characteristics such as conductivity and thermal conductivity are excellent. A copper porous composite member can be obtained. In addition, as a member main body, a board, a rod, a pipe | tube, etc. are mentioned, for example.

Here, in the method for producing a copper porous composite member of the present invention, a joining surface to which the copper porous body is joined in the member body is made of copper or a copper alloy, and the copper porous body It is preferable to join the member main body by sintering.
In this case, the member main body and the copper porous body can be integrated by sintering, and a copper porous composite member having excellent characteristic stability can be manufactured.

  According to the present invention, a copper porous body having high porosity and sufficient conductivity and thermal conductivity, a copper porous composite member in which the copper porous body is joined to a member body, and a copper porous body The manufacturing method and the manufacturing method of a copper porous composite member can be provided.

It is an expansion schematic diagram of the copper porous body which is 1st embodiment of this invention. It is a graph which shows the circularity of a regular polygon. It is a schematic explanatory drawing of the cross-sectional shape of the copper fiber which comprises the frame | skeleton part of the copper porous body shown in FIG. It is a flowchart which shows an example of the manufacturing method of the copper porous body shown in FIG. It is explanatory drawing which shows the manufacturing process which manufactures the copper porous body shown in FIG. It is external appearance explanatory drawing of the copper porous composite member which is 2nd embodiment of this invention. It is a flowchart which shows an example of the manufacturing method of the copper porous composite member shown in FIG. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention. It is an external view of the copper porous composite member which is other embodiment of this invention.

  Hereinafter, a copper porous body, a copper porous composite member, a copper porous body manufacturing method, and a copper porous composite member manufacturing method according to embodiments of the present invention will be described with reference to the accompanying drawings. .

(First embodiment)
First, the copper porous body 10 which is 1st embodiment of this invention is demonstrated with reference to FIGS.
The copper porous body 10 which is this embodiment has the frame | skeleton part 12 in which the some copper fiber 11 was sintered as shown in FIG.

In the copper porous body 10 according to the present embodiment, the porosity P is in the range of 50% to 90%.
The porosity P was calculated by the following formula using the true density D _T (g / cm ³ ). The mass of the copper porous body was m (g), and the volume of the copper porous body was V (cm ³ ).
Porosity P (%) = (1− (m / (V × D _T ))) × 100

Furthermore, in the copper porous body 10 which is this embodiment, electric conductivity (sigma) _P (% IACS) of the copper porous body 10 measured by the 4-terminal method based on JISC2525 is used for the copper porous body 10. apparent density ratio porosity standards influencing for good conductivity, which is defined by dividing the _{D a σ N} (% IACS) is a 18% IACS or more. The porosity normalized conductivity σ _N and the apparent density ratio D _A are calculated by the following equations, respectively.
Porosity normalized conductivity σ _N (% IACS) = σ _P × (1 / D _A )
Apparent density ratio D _A = m / (V × D _T )

Here, the copper fiber 11 which comprises the frame | skeleton part 12 consists of copper or a copper alloy, the diameter R shall be in the range of 0.01 mm or more and 1.0 mm or less, and ratio L / R of length L and diameter R Is in the range of 4 to 200. In this embodiment, the copper fiber 11 is comprised by C1020 (oxygen-free copper), for example.
In the present embodiment, the copper fiber 11 is given a shape such as twisting or bending. Further, in the copper porous body 10 is this embodiment, the apparent density ratio D _A is 0.50 or less of the true density D _T of the copper fibers 11. The shape of the copper fibers 11, to the extent that the apparent density ratio D _A is 0.50 or less of the true density D _T of the copper fibers 11, straight, but optionally including curved, at least one copper fibers 11 When a part that has been subjected to a predetermined shape imparting process by twisting or bending is used for the part, the gap shape between the copper fibers 11 can be formed three-dimensionally and isotropically, and as a result, the copper This leads to an improvement in isotropy of various properties such as conductivity and thermal conductivity of the porous body 10.

Note that the copper fiber 11 is adjusted to a predetermined diameter R by a drawing method, a coil cutting method, a chatter cutting method, a wire cutting method, a melt spinning method, and the like, and is further lengthened to satisfy a predetermined L / R. It is manufactured by adjusting and cutting.
Here, the diameter R is a value calculated on the basis of the cross-sectional area A of each fiber, and is defined by the following equation assuming a perfect circle regardless of the cross-sectional shape.
Diameter R = (A / π) ^1/2 × 2

And as for the copper fiber 11 which comprises the frame | skeleton part 12, the circularity C of the cross section orthogonal to a length direction is 0.92 or more and 1 or less.
Here, the circularity C is defined by the following equation, where A is the cross-sectional area of the copper fiber 11 and Q is the circumferential length of the cross-section of the copper fiber 11.
Circularity C = (4πA) ^0.5 / Q

The circularity C is 1 when it is a perfect circle, and the circularity C decreases as the circumferential length Q increases with respect to the cross-sectional area A. Therefore, when the cross section has a polygonal shape or a shape with a large aspect ratio, the circularity C decreases.
Here, the graph which shows the circularity C of a regular polygon is shown in FIG.

As shown in FIG. 2, in the case of a regular polygon, the circularity C is 0.92 or more when N is an integer of 5 or more in a regular N-gon.
And in this embodiment, as shown in FIG. 3, the cross-sectional shape of the copper fiber 11 which comprises the frame | skeleton part 12 shall be a substantially circular shape.

Here, when the diameter R of the copper fibers 11 is less than 0.01 mm, the bonding area between the copper fibers 11 is small, and there is a possibility that the electrical conductivity and the thermal conductivity are insufficient. On the other hand, when the diameter R of the copper fibers 11 exceeds 1.0 mm, the number of contact points where the copper fibers 11 are in contact with each other is insufficient, and there is a possibility that the conductivity and thermal conductivity are insufficient.
From the above, in this embodiment, the diameter R of the copper fiber 11 is set in the range of 0.01 mm or more and 1.0 mm or less. In addition, when aiming at the further improvement of electroconductivity and heat conductivity, it is preferable that the minimum of the diameter R of the copper fiber 11 shall be 0.03 mm or more, and the upper limit of the diameter R of the copper fiber 11 shall be 0.5 mm or less. It is preferable to do.

Further, when the ratio L / R of the length L and the diameter R of the copper fibers 11 is less than 4, the bulk density D _P and less than 50% of the true density D _T copper fibers 11 when stacked It is difficult to obtain a copper porous body 10 having a high porosity P. On the other hand, when the ratio L / R between the length L and the diameter R of the copper fibers 11 exceeds 200, the copper fibers 11 cannot be uniformly dispersed when stacked and disposed, and the uniform porosity P is obtained. There is a possibility that it may be difficult to obtain the copper porous body 10 having the same.
From the above, in this embodiment, the ratio L / R between the length L and the diameter R of the copper fiber 11 is set in the range of 4 or more and 200 or less. In order to further improve the porosity P, the lower limit of the ratio L / R between the length L and the diameter R of the copper fiber 11 is preferably 10 or more. In order to obtain a copper porous body 10 having a more uniform porosity P, the ratio L / R upper limit of the length L and the diameter R of the copper fibers 11 is preferably 100 or less.

Furthermore, when the cross-sectional shape of the copper fiber 11 forming the skeleton part 12 is a triangular shape, a high aspect ratio shape or the like and the circularity C is less than 0.92, the number of contact points between the copper fibers 11 during filling Is not ensured, and the contact area varies for each contact point due to the unevenness of the fiber cross section, so that it is difficult to form a uniform conductive path inside the sintered copper porous body 10, and the copper porous body 10 There is a possibility that the conductivity and thermal conductivity may be lowered.
This is because, in a three-dimensional network structure formed by bonding metal fibers, if the internal structure of the structure is non-uniform, the actual conduction path will be less than the distance between the measurement terminals of the conductivity (shortest distance). This is thought to be because it grows larger. In addition, if the internal structure is non-uniform, it also causes anisotropy. Therefore, in order to produce a metal fiber three-dimensional network structure excellent in conductivity and thermal conductivity, it is desirable that the joints between the fibers are sufficiently secured and that the area of the joints is small. .
From the above, in this embodiment, the circularity C of the cross section of the copper fiber 11 forming the skeleton part 12 is set to a range of 0.92 or more. In order to further improve the porosity P and the conductivity, it is preferable to set the lower limit of the circularity C of the cross section of the copper fiber 11 forming the skeleton part 12 to 0.95 or more.

Next, the manufacturing method of the copper porous body 10 which is this embodiment is demonstrated with reference to the flowchart of FIG. 4, the process drawing of FIG.
First, as shown in FIG. 5, the copper fiber 11 described above is sprayed from the spreader 31 into the graphite container 32 to be bulk-filled, and the copper fiber 11 is stacked (copper fiber stacking step S01).
Here, in the copper fibers laminating step S01, a bulk density D _P after filling is stacked a plurality of copper fibers 11 to be equal to or less than 40% of the true density D _T of the copper fibers 11. In addition, in this embodiment, since shape provision processing, such as a twist process and a bending process, is given to the copper fiber 11, a three-dimensional and isotropic space | gap is ensured between the copper fibers 11 at the time of lamination | stacking. become.

Next, the copper fiber 11 bulk-filled in the graphite container 32 is charged into the atmosphere heating furnace 33 and heated and sintered in a reducing atmosphere, an inert gas atmosphere or a vacuum atmosphere (sintering step S02). .
The heating conditions of the sintering step S02 in the present embodiment are set such that the holding temperature is 500 ° C. or higher and 1050 ° C. or lower, and the holding time is 5 minutes or longer and 600 minutes or shorter.

Here, when the holding temperature in sintering process S02 is less than 500 degreeC, there exists a possibility that sintering rate may be slow and sintering may not fully advance. On the other hand, when the holding temperature in sintering process S02 exceeds 1050 degreeC, it will heat to the melting | fusing point vicinity of copper, and there exists a possibility that the electroconductivity and the porosity P may fall.
From the above, in this embodiment, the holding temperature in the sintering step S02 is set to 500 ° C. or higher and 1050 ° C. or lower. In order to reliably sinter the copper fiber 11, it is preferable that the lower limit of the holding temperature in the sintering step S02 is 600 ° C. or higher and the upper limit of the holding temperature is 1000 ° C. or lower.

In addition, when the holding time in the sintering step S02 is less than 5 minutes, the sintering speed is slow and the sintering may not proceed sufficiently. On the other hand, if the holding time in the sintering step S02 exceeds 600 minutes, the thermal shrinkage due to the sintering may increase and the porosity P may decrease.
From the above, in this embodiment, the holding time in the sintering step S02 is set in the range of 5 minutes or more and 600 minutes or less. In order to reliably sinter the copper fiber 11, it is preferable that the lower limit of the holding time in the sintering step S02 is 10 minutes or more and the upper limit of the holding time is 180 minutes or less.

  Further, the atmosphere in the sintering step S02 may be a reducing gas such as hydrogen gas, RX gas, ammonia decomposition gas, nitrogen-hydrogen mixed gas, argon-hydrogen mixed gas, or nitrogen gas, argon gas, etc. An inert gas may be used. Furthermore, it is good also as a vacuum atmosphere of 100 Pa or less.

By this sintering step S02, the sintering proceeds at the contact portion between the copper fibers 11, and the copper fibers 11 are joined together to form the skeleton portion 12.
Here, in this embodiment, since the sintering step S02 is performed in a reducing atmosphere, an inert atmosphere, and a vacuum atmosphere without applying pressure as described above, the bulk shape and the surface shape of the copper fiber 11 are greatly changed. The circularity C of the cross section hardly changes before and after sintering.

  According to the copper porous body 10 of the present embodiment configured as described above, the diameter R is in the range of 0.01 mm or more and 1.0 mm or less, and the ratio L between the length L and the diameter R is L. Since the skeleton part 12 is formed by sintering the copper fiber 11 having a / R in the range of 4 or more and 200 or less, a sufficient gap is secured between the copper fibers 11, The shrinkage rate during sintering can be suppressed, the porosity P is high, and the dimensional accuracy is excellent.

And in this embodiment, since the circularity C of the cross section of the copper fiber 11 forming the skeleton part 12 is 0.92 or more, the number of contact points between the copper fibers 11 is sufficiently secured, and after sintering It becomes possible to improve electroconductivity and heat conductivity, and to ensure a space | gap between the copper fibers 11, and to make the porosity P high.
Therefore, according to this embodiment, it is possible to provide the copper porous body 10 having a porosity P as high as 50% or more and 90% or less and having excellent conductivity and thermal conductivity. .

(Second embodiment)
Next, the copper porous composite member 100 which is 2nd embodiment of this invention is demonstrated with reference to attached drawing.
In FIG. 6, the copper porous composite member 100 which is this embodiment is shown. The copper porous composite member 100 includes a copper plate 120 (member main body) made of copper or a copper alloy, and a copper porous body 110 bonded to the surface of the copper plate 120.

  Here, the copper porous body 110 according to the present embodiment is obtained by sintering a plurality of copper fibers to form a skeleton, as in the first embodiment. And in the copper porous body 110 which concerns on this embodiment, the porosity P is made into the range of 50% or more and 90% or less.

Here, the copper fiber forming the skeleton is made of copper or a copper alloy, the diameter R is in the range of 0.01 mm to 1.0 mm, and the ratio L / R of the length L to the diameter R is L / R. The range is 4 or more and 200 or less. In the present embodiment, the copper fiber is made of, for example, C1020 (oxygen-free copper).
And the copper fiber which forms a frame | skeleton part is made into the range whose circularity C of the cross section orthogonal to a length direction is 0.92 or more.
In the present embodiment, the copper fiber is given a shape such as twisting or bending. Further, in the copper porous body 110 is a present embodiment, the apparent density ratio D _A is 50% or less of the true density D _T of copper fibers.

Next, a method for manufacturing the copper porous composite member 100 according to the present embodiment will be described with reference to the flowchart of FIG.
First, the copper plate 120 which is a member main body is prepared (copper plate arrangement | positioning process S100). Next, copper fibers are dispersed and arranged on the surface of the copper plate 120 (copper fiber lamination step S101). Here, in the copper fibers lamination step S101, bulk density D _P is stacked a plurality of copper fibers to be equal to or less than 40% of the true density D _T of copper fibers.

Next, the copper fibers stacked and arranged on the surface of the copper plate 120 are sintered to form the copper porous body 110, and the copper porous body 110 and the copper plate 120 are bonded (sintering and joining step S102).
The heating conditions of the sintering and joining step S102 in the present embodiment are set such that the holding temperature is 500 ° C. or higher and 1050 ° C. or lower, and the holding time is 5 minutes or longer and 600 minutes or shorter.
Furthermore, the atmosphere in the sintering and joining step S102 is a reducing atmosphere, an inert gas atmosphere, or a vacuum atmosphere, and specifically, hydrogen gas, RX gas, ammonia decomposition gas, nitrogen-hydrogen mixed gas, argon -A reducing gas such as a hydrogen mixed gas may be used, or an inert gas such as nitrogen gas or argon gas may be used. Furthermore, it is good also as a vacuum atmosphere of 100 Pa or less.

  By this sintering and joining step S102, the copper fibers are sintered to form the copper porous body 110, and the copper fibers and the copper plate 120 are sintered, so that the copper porous body 110 and the copper plate 120 are joined. Then, the copper porous composite member 100 according to this embodiment is manufactured.

According to the copper porous composite member 100 of the present embodiment configured as described above, the circularity C of the cross section of the copper fiber constituting the copper porous body 110 is set to a range of 0.92 or more. Therefore, the number of contact points between the copper fibers is sufficiently ensured, it is possible to improve the conductivity and thermal conductivity, and it is possible to secure a gap between the copper fibers, and the copper porous body 110 It becomes possible to increase the porosity P.
As a result, it is possible to greatly improve various characteristics such as heat exchange efficiency, water retention and evaporation efficiency when the copper porous composite member 100 is used as a heat exchange member such as an evaporator.

  Moreover, according to the manufacturing method of the copper porous composite member 100 which is this embodiment, a copper fiber is laminated | stacked on the surface of the copper plate 120 which consists of copper and a copper alloy, and sintering and joining are carried out by sintering and joining process S102. Since it is carried out at the same time, the manufacturing process can be simplified.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, although it demonstrated as what manufactures a copper porous body using the manufacturing equipment shown in FIG. 5, it is not limited to this, Even if it manufactures a copper porous body using another manufacturing equipment Good.

  In the present embodiment, the copper fiber made of oxygen-free copper (JIS C1020) has been described. However, the present invention is not limited to this. Phosphorus deoxidized copper (JIS C1201, C1220) or tough pitch copper ( Highly conductive copper alloys such as pure copper such as JIS C1100), Cr copper (C18200) and Cr—Zr copper (C18150) may be used.

Furthermore, in 2nd embodiment, although the joining method in which the sintered layer was formed in the junction part of a copper porous body and a member main body was illustrated as a desirable method, it is not limited to this, Various welding methods The copper porous body and the member main body may be joined by a joining method using a laser welding method or a resistance welding method or a brazing method using a brazing material that melts at a low temperature.
In the second embodiment, the copper porous composite member having the structure shown in FIG. 6 has been described as an example. However, the present invention is not limited to this, and the copper having the structure shown in FIGS. It may be a porous composite member.

For example, as shown in FIG. 8, a copper porous composite member 200 having a structure in which a plurality of copper tubes 220 are inserted into a copper porous body 210 as a member main body may be used.
Alternatively, as shown in FIG. 9, a copper porous composite member 300 having a structure in which a copper tube 320 curved in a U shape as a member main body is inserted into a copper porous body 310 may be used.

Furthermore, as shown in FIG. 10, the copper porous composite member 400 of the structure which joined the copper porous body 410 to the internal peripheral surface of the copper pipe 420 which is a member main body may be sufficient.
Moreover, as shown in FIG. 11, the copper porous composite member 500 of the structure which joined the copper porous body 510 to the outer peripheral surface of the copper pipe 520 which is a member main body may be sufficient.

Furthermore, as shown in FIG. 12, a copper porous composite member 600 having a structure in which a copper porous body 610 is bonded to the inner peripheral surface and the outer peripheral surface of a copper tube 620 that is a member main body may be used.
Moreover, as shown in FIG. 13, the copper porous composite member 700 of the structure which joined the copper porous body 710 to both surfaces of the copper plate 720 which is a member main body may be sufficient.

Furthermore, as shown in FIG. 14, a copper porous composite member 800 having a structure in which a copper porous body 810 is joined inside a copper tube 820 that is a member main body may be used.
Moreover, as shown in FIG. 15, the copper porous composite member 900 of the structure which joined the copper porous body 910 to the inner surface of the flat copper tube 920 which is a member main body may be sufficient.

Below, the result of the confirmation experiment performed in order to confirm the effect of this invention is demonstrated.
A copper porous sintered body having a width of 30 mm, a length of 200 mm, and a thickness of 5 mm was manufactured using the sintering raw material (copper fiber) shown in Table 1 by the manufacturing method described in the above embodiment. In addition, the diameter R of the copper fiber used as a raw material, the ratio L / R of the length L to the diameter R, and the circularity C were measured as follows.
In addition, for the obtained copper porous sintered body, the diameter R of the cross section of the copper fiber forming the skeleton part, the ratio L / R of the length L to the diameter R, the circularity C, the porosity, the porosity standard The electrical conductivity was evaluated as follows. The evaluation results are shown in Table 2.

(Copper fiber diameter R)
A circle calculated by image processing using a photographed image by observing a cross section orthogonal to the length direction of the copper fiber taken out of the sintered raw material and the copper fiber taken from the copper porous sintered body with an optical microscope A simple average value of converted diameter (Heywood diameter) R = (A / π) ^0.5 × 2 was calculated. This was designated as the diameter R of the copper fiber.

(L / R ratio between length L and diameter R)
The length L of the copper fiber is calculated by performing image analysis on the copper fiber used as a sintering raw material and the copper fiber taken out of the copper porous sintered body using a particle analyzer “Morphology G3” manufactured by Malvern. A simple average value was used. Using this, the ratio L / R between the length L and the diameter R was calculated.

(Circularity C of cross section)
Sections perpendicular to the length direction of the copper fibers taken out of the sintered raw material and the copper porous sintered body were observed with an optical microscope, and were calculated by image processing using the photographed images. It calculated with the following formula | equation using the area A (mm < ² >) and the simple average value of perimeter length Q (mm).
Circularity C = (4πA) ^0.5 / Q

(Porosity P)
The true density D _T (g / cm ³ ) was measured by an underwater method using a precision balance, and the porosity P was calculated by the following equation. The mass of the copper porous sintered body was m (g), and the volume of the copper porous sintered body was V (cm ³ ).
Porosity P (%) = (1− (m / (V × D _T ))) × 100

(Porosity normalized conductivity)
Using a sample cut into a plate shape having a width of 30 mm, a length of 200 mm, and a thickness of 5 mm, a voltage ohmic tester 3227 manufactured by Hioki Electric Co., Ltd. was used in accordance with JIS C 2525. The conductivity σ _P (% IACS) was measured by the four-terminal method under the condition of 5A. And the porosity normalized electrical conductivity (sigma) _N was computed with the following formula | equation.
Porosity normalized conductivity σ _N (% IACS) = σ _P × (1 / D _A )

  In any of Invention Example 1-12 and Comparative Example 1-6, the copper fiber as the sintering raw material and the copper fiber taken out from the copper porous sintered body had a diameter R, a length L and a diameter R. It was confirmed that the ratio L / R and the circularity C of the cross section did not change greatly.

Here, in Comparative Example 1 in which the diameter R of the copper fiber was 0.005 mm and in Comparative Example 2 in which the diameter R of the copper fiber was 1.20 mm, the porosity normalized conductivity of the copper porous sintered body Is confirmed to be low.
Further, in Comparative Example 3 in which the ratio L / R between the length L and the diameter R of the copper fiber was 3, the porosity P was as low as 47%.
Furthermore, in Comparative Example 4 in which the ratio L / R between the length L and the diameter R of the copper fiber is 250, the porosity normalized conductivity is low. This is presumed to be due to the presence of a portion having a large gap in part, and the uniformity of the internal conduction path was greatly reduced.

  In Comparative Example 5 in which the circularity C of the cross section of the copper fiber was 0.80 and in Comparative Example 6 in which the circularity C was 0.53, the porosity normalized conductivity was low. This is presumably because the number of contact points between the copper fibers has decreased.

On the other hand, in the copper porous sintered body of the present invention example, the porosity was as high as 50% or more, and the porosity normalized conductivity was sufficiently ensured. In addition, in the copper porous sintered body of the example of this invention, it is excellent also in the heat conductivity which uses a free electron as a carrier similarly to electrical conduction.
From the above, according to the present invention, it was confirmed that a high-quality copper porous sintered body having a high porosity and sufficient conductivity and thermal conductivity can be provided.

10, 110 Copper porous body 11 Copper fiber 12 Skeletal part 100 Copper porous composite member 120 Copper plate (member main body)

Claims (6)

A copper porous body comprising a sintered body of a plurality of copper fibers and having a three-dimensional network structure skeleton,
The copper fiber forming the skeleton is made of copper or a copper alloy, the diameter R is in the range of 0.01 mm or more and 1.0 mm or less, and the ratio L / R of the length L to the diameter R is 4 or more. The circularity of the cross section orthogonal to the length direction is 0.92 or more while being within a range of 200 or less,
A porous copper body having a porosity of 50% or more and 90% or less. A copper porous composite member comprising a joined body of a member main body and a copper porous body having a three-dimensional network structure skeleton,
The said copper porous body is a copper porous body of Claim 1, The copper porous composite member characterized by the above-mentioned.   The joint surface of the member main body with the copper porous body is made of copper or a copper alloy, and the joint portion between the copper porous body and the member main body is a sintered layer. Item 3. A copper porous composite member according to Item 2. A method for producing a porous copper body comprising a sintered body of a plurality of copper fibers and having a three-dimensional network structure skeleton,
The diameter R is in the range of 0.01 mm or more and 1.0 mm or less, the ratio L / R of the length L to the diameter R is in the range of 4 or more and 200 or less, and the circularity of the cross section is 0. A copper fiber laminating step of laminating the copper fibers of 92 or more;
And a sintering step of sintering a plurality of the laminated copper fibers. A method for producing a copper porous body, comprising: A method for producing a copper porous composite member comprising a joined body of a member main body and a copper porous body having a three-dimensional network structure skeleton,
The manufacturing method of the copper porous composite member characterized by including the joining process which joins the copper porous body of Claim 1, and the said member main body.   The joining surface to which the copper porous body is joined among the member bodies is made of copper or a copper alloy, and the joining step joins the copper porous body and the member body by sintering. The method for producing a copper porous composite member according to claim 5.

Images