JP2018188711A - Metal-carbon particle composite material and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal-carbon particle composite material of which physical anisotropy in a planar direction of an entire composite material is alleviated and a production method thereof.SOLUTION: A metal-carbon particle composite material 20 is obtained by joining and integrating a metal layer B made of a metal matrix 21 and a carbon particle dispersion layer C in which carbon particles 1 are dispersed in the metal matrix 21 in a state where a plurality of these layers are alternately laminated. An orientation direction E of the carbon particle 1 of at least one carbon particle dispersion layer C of a plurality of carbon particle dispersion layers C is different from the orientation direction E of the carbon particle 1 of at least the another carbon particle dispersion layer C.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a metal-carbon particle composite material including a metal matrix and carbon particles dispersed in the metal matrix, a manufacturing method thereof, and a cooler.

  Although the vertical direction of the metal-carbon particle composite material according to the present invention is not limited, in this specification, in order to facilitate understanding of the configuration of the composite material, the thickness direction of the composite material and the laminate The thickness direction is defined as the vertical direction of the composite material and the vertical direction of the laminate, respectively.

  Metal-carbon particle composite materials generally have high thermal conductivity and low linear expansion. Documents disclosing a method for manufacturing this type of composite material include Japanese Patent No. 5150905 (Patent Document 1), Japanese Patent No. 4441768 (Patent Document 2), and Japanese Patent Application Laid-Open No. 2006-1232 (Patent Document 3). .

  Japanese Patent No. 5150905 discloses a preform in which a film containing carbon fibers as carbon particles is formed on a sheet-like or foil-like metal support, and a plurality of these are stacked to form a laminate, A method for producing a metal-based carbon fiber composite material as a metal-carbon particle composite material by integrating preforms by heat-welding the body is disclosed. In this method, in the obtained composite material, the thermal conductivity is increased only in one direction in which the carbon fibers are oriented.

  Japanese Patent No. 4441768 discloses a metal-carbon particle composite by forming a sintered precursor using a mixture of scaly graphite powder and a predetermined scaly metal powder, and sintering the sintered precursor while applying pressure. A method for producing a metal-graphite composite material as a material is disclosed. This method has problems that it is difficult to handle the metal powder at the time of manufacture and that the manufacturing cost is high.

  Japanese Patent Laid-Open No. 2006-1232 discloses a high thermal conductivity / low thermal expansion composite as a metal-carbon particle composite by hot pressing sintering a composite in which a crystalline carbon material layer and a metal layer are laminated and combined. A method of manufacturing a material is disclosed. In this method, it is difficult to sinter the composite, and therefore, it is considered that the joining is insufficient and the joining interface tends to shift.

  As other documents disclosing metal-carbon particle composite materials, there are JP-A-2015-25158 (Patent Document 4) and JP-A-2015-217655 (Patent Document 5).

  Thus, the metal-carbon particle composite material obtained by the manufacturing method disclosed in the above-mentioned Japanese Patent No. 5150905 includes a metal layer composed of a metal matrix and carbon fibers (as carbon particles) dispersed in the metal matrix. The dispersion layers (as carbon particle dispersion layers) are joined and integrated in a state where a plurality of layers are alternately laminated.

  Hereinafter, in the metal-carbon particle composite material, the stacking direction of the metal layer and the carbon particle dispersion layer is defined as the thickness direction of the composite material (that is, the vertical direction of the composite material). Further, a plane perpendicular to the thickness direction of the composite material is defined as a “plane” of the composite material, and a plane direction perpendicular to the thickness direction of the composite material is defined as the “planar direction” of the composite material.

Japanese Patent No. 5150905 Japanese Patent No. 4441768 JP 2006-1232 A Japanese Patent Laying-Open No. 2015-25158 JP2015-217655A

  In the metal-carbon particle composite material of the above-mentioned Japanese Patent No. 5150905, when the fiber axis directions of the carbon fibers of each carbon fiber dispersion layer are all aligned in one direction within the plane of the composite material, the physical properties of the composite material (example: The thermal conductivity and linear expansion coefficient) greatly differ between the orientation direction of the carbon fibers in the plane of the composite material and the direction perpendicular thereto. Therefore, there has been a problem that the composite material is easily distorted when the composite material is heated.

  The present invention has been made in view of the above-described technical background, and an object thereof is to provide a metal-carbon particle composite material in which anisotropy of physical properties in the planar direction of the entire composite material is relaxed, and a method for producing the same. And it is providing the cooler which has high reliability with respect to a temperature change.

  The present invention provides the following means.

[1] A metal layer composed of a metal matrix and a carbon particle dispersion layer in which carbon particles are dispersed in the metal matrix are joined and integrated in a state of being alternately stacked.
The metal-carbon in which the orientation direction of the carbon particles of at least one of the plurality of carbon particle dispersion layers is different from the orientation direction of the carbon particles of at least one other carbon particle dispersion layer. Particle composite material.

  [2] The metal layer and the carbon particle dispersion layer are arranged in a state where a plurality of layers are alternately laminated so that the orientation direction of the carbon particles of the carbon particle dispersion layer regularly changes in the thickness direction of the composite material. 2. The metal-carbon particle composite material according to 1 above.

  [3] The metal-carbon particle composite material according to item 1 or 2, wherein the metal matrix is an aluminum matrix.

[4] A cooler for cooling the heating element,
A plurality of cooler constituent layers joined and integrated in a laminated manner,
A cooler in which at least one of the plurality of constituent layers is made of the metal-carbon particle composite material according to any one of the preceding items 1 to 3.

[5] A step of obtaining a coating foil in which a carbon particle layer is formed on the planned coating surface of the metal foil by coating a coating liquid containing carbon particles on the planned coating surface of the metal foil;
Cutting the coating foil to obtain a material foil;
Forming a laminate by laminating a plurality of the material foils;
A step of sintering the laminate,
In the step of forming the laminate, the coating direction of the coating liquid in at least one of the material foils is the coating direction of the coating liquid in the at least one other material foil of the plurality of material foils. A method for producing a metal-carbon particle composite material that is laminated differently.

  [6] In the step of forming the laminate, the material foil is laminated in a plurality of numbers so that the coating direction of the coating liquid in the material foil regularly changes in the thickness direction of the laminate. The manufacturing method of the metal-carbon particle composite material of description.

[7] In the step of forming the laminated body, a plurality of the material foils are laminated to form a first laminated body, and then the first laminated body is cut to obtain a second laminated body,
7. The method for producing a metal-carbon particle composite material according to 5 or 6 above, wherein in the step of sintering the laminate, the second laminate as the laminate is sintered.

  [8] The method for producing a metal-carbon particle composite material according to any one of items 5 to 7, wherein the metal foil is an aluminum foil.

  The present invention has the following effects.

  According to the preceding item [1], in the metal-carbon particle composite material, the orientation direction of the carbon particles of at least one carbon particle dispersion layer among the plurality of carbon particle dispersion layers is the carbon particles of at least one other carbon particle dispersion layer. By being different from the orientation direction, the anisotropy of physical properties in the planar direction of the entire composite material can be relaxed.

  In the previous item [2], the metal layers and the carbon particle dispersion layers are arranged in a state where a plurality of layers are alternately laminated so that the orientation direction of the carbon particles of the carbon particle dispersion layer regularly changes in the thickness direction of the composite material. Accordingly, the anisotropy of the physical properties in the planar direction of the entire composite material can be surely reduced.

  In the above item [3], since the metal matrix is an aluminum matrix, the weight of the composite material can be reduced, and the workability of the composite material can be improved.

  In the preceding item [4], it is possible to provide a cooler having high reliability against temperature changes such as a cooling / heating cycle.

  According to the preceding item [5], in the step of forming the laminate, the application direction of the coating liquid in at least one material foil is applied to the plurality of material foils in the at least one other material foil. By laminating so as to be different from the direction, the anisotropy of the physical properties in the planar direction of the entire composite material obtained can be relaxed.

  In the preceding item [6], the anisotropy of the physical properties in the planar direction of the entire composite material to be obtained can be surely reduced.

  In the previous item [7], since the second laminate is obtained by cutting the first laminate, a laminate having a small cross-sectional area in the plane direction can be easily obtained. And the composite material with a small cross-sectional area of a plane direction can be easily obtained by sintering this 2nd laminated body.

  In the previous item [8], the obtained composite material can be reduced in weight, and the workability of the composite material can be improved.

FIG. 1 is a schematic cross-sectional view of a metal-carbon particle composite material according to an embodiment of the present invention. FIG. 2 is a flowchart showing a method for manufacturing the composite material. FIG. 3 is a schematic diagram illustrating a process of obtaining a coating foil. FIG. 4A is a plan view showing an arrangement state of lattice-type cells on the peripheral surface of the gravure roll. FIG. 4B is a perspective view showing the shape of the lattice-type cell of FIG. 4A. FIG. 5A is a plan view showing an arrangement state of pyramidal cells on the peripheral surface of the gravure roll. FIG. 5B is a perspective view showing the shape of the pyramidal cell of FIG. 5A. FIG. 6A is a plan view showing an arrangement state of turtle shell cells on the peripheral surface of the gravure roll. FIG. 6B is a perspective view showing the shape of the turtle shell cell of FIG. 6A. FIG. 7A is a plan view showing an arrangement state of circular cells on the peripheral surface of the gravure roll. FIG. 7B is a perspective view showing the shape of the circular cell of FIG. 7A. FIG. 8A is a side view of the cell when the bottom surface of the cell is flat. FIG. 8B is a side view of the cell when the bottom surface of the cell has a concave curved surface shape. FIG. 8C is a side view of the cell when the bottom surface of the cell has a concave conical shape. FIG. 9 is a perspective view of the cell when a communication port is provided on the inner peripheral side surface of the cell. FIG. 10 is a schematic diagram illustrating a process of cutting a coating foil to obtain a plurality of material foils. FIG. 11 is a schematic diagram illustrating a process of forming a laminate by laminating a plurality of material foils. FIG. 12 is a schematic view for explaining a step of sintering the laminated body. FIG. 13 is a diagram (graph) illustrating an example of a temperature rise curve when a laminated body is heated. FIG. 14 is a schematic perspective view of the composite material. FIG. 15 is a schematic side view of the cooler. FIG. 16 is a schematic diagram illustrating some examples of the arrangement of the material foils in the stacking direction in the step of forming a stacked body. FIG. 17 is a schematic plan view showing a material foil having a reference numeral attached to FIG. FIG. 18 is a schematic diagram illustrating some examples of the arrangement in the stacking direction of the carbon fiber dispersion layers of the composite material. FIG. 19 is a schematic diagram illustrating a case where a plurality of second stacked bodies are obtained by cutting the first stacked body.

  Next, several embodiments of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, a metal-carbon particle composite (metal-carbon particle composite) 20 according to an embodiment of the present invention includes a metal layer B composed of a metal matrix (shown by dot hatching) 21, and a metal matrix. The carbon fiber dispersion layer C as a carbon particle dispersion layer in which carbon fibers 1 as carbon particles are dispersed in 21 is joined and integrated into a state where a plurality of layers are alternately laminated. A large number of carbon fibers 1 are dispersed in each carbon fiber dispersion layer C.

  In the composite material 20, among the plurality of carbon fiber dispersion layers C, the orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C labeled with “C1” is the length direction of the composite material 20 (that is, in FIG. 1). The horizontal direction of the paper). The orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C to which the symbol “C2” is attached is a direction different from the orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C1, and more specifically, the composite material 20 1 in the width direction (that is, the direction perpendicular to the paper surface of FIG. 1). The thickness direction of the composite material 20, which is the stacking direction of the metal layer B and the carbon fiber dispersion layer C, coincides with the vertical direction of the composite material 20 (that is, the vertical direction of the paper surface of FIG. 1).

  In the composite material 20, the orientation direction E of the carbon fibers 1 of at least one carbon fiber dispersion layer C1 among the plurality of carbon fiber dispersion layers C is the same as the orientation direction E of the carbon fibers 1 of at least one other carbon fiber dispersion layer C2. It is different. Thereby, the anisotropy of the physical property (especially thermal characteristic) of the whole composite material is relieved. The thermal characteristics include thermal conductivity (thermal conductivity), linear expansion coefficient (linear thermal expansion), and the like.

  More specifically, in the composite material 20, the metal layer B and the carbon fiber dispersion layer C are oriented in the thickness direction of the composite material 20 (that is, the vertical direction of the composite material 20), and the orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C. Are arranged in a state of being stacked alternately so as to change regularly. More specifically, in the metal layer B and the carbon fiber dispersion layer C, the orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C is clockwise (or counterclockwise) in plan view in the thickness direction of the composite material 20. A plurality of layers are alternately stacked so as to change by 90 °. Thereby, in the composite material 20, the anisotropy of the physical property of the whole composite material in the plane direction is reliably relieved.

  Here, the orientation direction of the carbon particles in the carbon particle dispersion layer means the orientation direction of the longest axis of the carbon particles in the carbon particle dispersion layer. Therefore, when the carbon particles are carbon fibers 1 as in this embodiment, the orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C means the orientation direction of the fiber axes of the carbon fibers 1 of the carbon fiber dispersion layer C. doing.

  Next, the manufacturing method of the composite material 20 of this embodiment is demonstrated below.

  As shown in FIG. 2, the manufacturing method of the composite material 20 includes a step S1 for obtaining a coating foil, a step S2 for obtaining a material foil, a step S3 for forming a laminate, and a step S4 for sintering the laminate. These steps are performed in the order of this description.

  As shown in FIG. 3, in step S1 for obtaining a coating foil, a coating solution 5 containing carbon fibers 1 as carbon particles is coated with a long strip-shaped metal foil 10 (that is, a strip of the metal foil 10). By coating the surface 10a continuously in one direction in a layered manner, a long strip-shaped coating foil 12 (that is, coated) in which the carbon fiber layer 11 is formed (coated) on the surface 10a to be coated of the metal foil 10 is applied. This is a process for obtaining the strip material of the working foil 12. In the present embodiment, the coating direction D of the coating liquid 5 is the length direction of the metal foil 10.

  The application surface 10 a of the metal foil 10 is a surface on at least one side of both surfaces in the thickness direction of the metal foil 10. In the present embodiment, the planned coating surface 10a is a surface on one side in the thickness direction of the metal foil 10, and more specifically the upper surface of the metal foil 10.

  The coating liquid 5 contains the carbon fiber 1 as described above, and further contains a binder 2 and a solvent 2 for the binder 2 in a mixed state.

  The step S1 for obtaining the coating foil further includes a step S1a for removing the solvent 3 from the carbon fiber layer 11 formed on the surface 10a to be coated of the metal foil 10 (see FIG. 2).

  The process S2 for obtaining the material foil is a process of cutting the material foil 13 from the coating foil 12 by cutting the coating foil 12 into a predetermined shape as shown in FIG. That is, the material foil 13 is made of a cut piece obtained by cutting the coating foil 12. The shape of the material foil 13 is, for example, a circular shape.

  The step S3 of forming a laminate is a step of forming a laminate 15 by laminating a plurality of material foils 13, as shown in FIG.

  In step S4 of sintering the laminate 15, as shown in FIG. 12, the laminate 15 is heated by pressing the laminate 15 in the thickness direction of the laminate 15, thereby sintering the material foil 13. Sintered and integrated. This process S4 includes process S4a which removes the binder 2 from the laminated body 15 by heating the laminated body 15 (refer FIG. 2).

  Next, each step will be described in detail below.

<Step S1 for obtaining coating foil 12>
As shown in FIG. 3, the coating liquid 5 used in this step S1 contains the carbon fiber 1, the binder 2, and the solvent 3 in a mixed state as described above. For example, the coating liquid 5 is obtained as follows. It is done.

  A large number of carbon fibers 1, a binder 2, and a solvent 3 are placed in a mixing container 7 and these are stirred and mixed by a stirrer 8. Thereby, the coating liquid 5 containing the carbon fiber 1, the binder 2, and the solvent 3 in a mixed state is obtained. If necessary, a dispersing agent, an antifoaming agent, a surface adjusting agent, a viscosity adjusting agent, and the like may be further added to the coating liquid 5 by mixing them in the mixing container 7 and stirring and mixing them.

  The stirrer 8 is not limited, and a stirrer with a stirring blade, a planetary mixer, a homodisper, a bead mill, or the like can be used.

  Specific descriptions of the carbon fiber 1, the binder 2, and the solvent 3 will be described later.

  The coating method for coating the coating liquid 5 on the coating scheduled surface 10a of the metal foil 10 is not limited. Preferably, the coating liquid 5 is applied by a roll-to-roll method using an unwinding roll 37a for unwinding the metal foil 10 and a winding roll 37b for unwinding the metal foil 10, as shown in FIG. Is called.

  Between the unwinding roll 37a and the winding roll 37b, a gravure coating device (eg, gravure coater) 30 as a coating device and a drying furnace 38 as a drying device are arranged in the feeding direction F of the metal foil 10. It is installed at.

  The gravure coating apparatus 30 is a direct gravure coating apparatus (for example, a direct gravure coater) in detail. The gravure roll 31, the backup roll 33, and the coating liquid 5 is attached to the peripheral surface 31 a of the gravure roll 31. The liquid adhesion means 35 etc. are provided.

  On the peripheral surface 31a of the gravure roll 31, a large number of cells (concave portions) 32 are arranged in an orderly manner over the entire surface (see FIGS. 4A, 5A, 6A and 7A). A partition wall 31b is formed between adjacent cells 32, and each cell 32 is partitioned by the partition wall 31b. The backup roll 33 is disposed to face the gravure roll 31.

  The rotation direction of the gravure roll 31 is normally set to the same direction as the feeding direction F of the metal foil 10. The peripheral speed of the gravure roll 31 is normally set equal to the feed speed of the metal foil 10.

  The coating liquid adhering means 35 includes a coating liquid pan (not shown) containing the coating liquid 5, and a part of the circumferential surface 31a of the gravure roll 31 in the circumferential direction is coated in the pan. The gravure roll 31 rotates around its central axis in contact with the liquid 5, so that the coating liquid 5 is attached to the peripheral surface 31 a of the gravure roll 31. The carbon fibers 1 in the coating liquid 5 in the pan are dispersed in the coating liquid 5 so that the fiber axis directions are random.

  The drying furnace 38 evaporates and removes the solvent 3 contained in the carbon fiber layer 11 from the carbon fiber layer 11 by heating and drying the carbon fiber layer 11 formed on the planned coating surface 10 a of the metal foil 10. belongs to.

  The gravure coating apparatus 30 shown in FIG. 3 is a roll-to-roll system as described above. In the gravure coating apparatus 30, the metal foil 10 unwound from the unwinding roll 37a is sequentially sequentially supplied in a substantially horizontal direction between the gravure roll 31 and the backup roll 33 and in the drying furnace 38 at a predetermined feed rate. After passing, it is taken up by the take-up roll 37b.

  The feed direction F of the metal foil 10 is set to the length direction of the metal foil 10, and the direction parallel to the feed direction F is determined by the gravure coating device 30 (specifically, the gravure roll 31 of the gravure coating device 30). This is the coating direction D of the coating liquid 5 onto the coating-scheduled surface 10 a of the metal foil 10. Further, the metal foil 10 is fed in the feeding direction F with the coating surface 10a facing upward.

  The gravure roll 31 is disposed on the upper side of the metal foil 10 (that is, on the surface 10a to be coated) so as to traverse the metal foil 10 over the entire width direction. Moreover, the backup roll 33 is arrange | positioned in the aspect which crosses the metal foil 10 over the whole width direction under the metal foil 10. As shown in FIG.

  When the metal foil 10 unwound from the unwinding roll 37 a passes between the gravure roll 31 and the backup roll 33 of the gravure coating apparatus 30, the gravure roll 31 causes the metal foil 10 to be applied on the surface 10 a to be coated. The coating liquid 5 is continuously applied in the length direction of the metal foil 10.

  That is, as the gravure roll 31 rotates, the coating liquid 5 adheres to the peripheral surface 31 a of the gravure roll 31 by the coating liquid attachment means 35 and enters each cell 32. Then, along with the rotation of the gravure roll 31, excess coating liquid 5 adhering to the peripheral surface 31 a of the gravure roll 31 is scraped off by a doctor blade (scraper) 34. Then, the coating liquid 5 in the cell 32 is transferred onto the coating application surface 10a of the metal foil 10 by the peripheral surface 31a of the gravure roll 31 coming into contact with the application application surface 10a of the metal foil 10, A carbon fiber layer 11 made of the transfer-coated coating solution 5 is formed on the planned coating surface 10a. Thereby, the elongate strip | belt-shaped coating foil 12 (namely, strip material of the coating foil 12) in which the carbon fiber layer 11 was formed on the coating expected surface 10a of the metal foil 10 is obtained.

  In the gravure roll 31 of the gravure coating apparatus 30, the shape of the cell 32 is, for example, a cup shape, and the periphery of the cell 32 is substantially closed over the entire circumference.

  Specifically, the shape of the cell 32 includes a lattice type 32A (see FIGS. 4A and AB), a pyramid type 32B (see FIGS. 5A and 5B), a turtle shell type 32C (see FIGS. 6A and 6B), and a circular type 32D (see FIG. Preferably at least one selected from the group consisting of: see FIGS. 7A and 7B.

  As shown in FIGS. 4A and 4B, the lattice type cell 32A is formed to be recessed in a quadrangular pyramid shape.

  As shown in FIGS. 5A and 5B, the pyramid type cell 32B is formed to be recessed in a quadrangular pyramid shape.

  As shown in FIGS. 6A and 6B, the turtle shell cell 32C is formed in a hexagonal truncated cone shape.

  As shown in FIGS. 7A and 7B, the circular cell 32D is formed in a truncated cone shape.

  Further, the shape of the bottom surface 32b of the cell 32 (eg, lattice type, pyramid type, turtle shell type, circular type) is not limited, and may be flat as shown in FIG. 8A, for example. As shown in FIG. 8B, it may have a concave curved surface shape (eg, concave spherical shape), or may have a concave cone surface shape (eg, concave pyramid surface shape, concave conical surface shape) as shown in FIG. 8C. Furthermore, a shape in which at least two of these shapes are combined may be used.

  Furthermore, in this embodiment, it is desirable that the cell 32 has a shape in which the periphery of the cell 32 is completely closed over the entire circumference. However, the present invention is not limited to this, and as shown in FIG. A shape in which a small communication port 32 c for allowing a part of the coating liquid 5 in the cell 32 to flow into the adjacent cell 32 may be formed in a part of the inner peripheral side surface 32 a of the 32. .

  The size of the cell 32 is sufficient to allow the carbon fibers 1 having an average fiber length to enter the cell 32 in a state substantially parallel to the opening surface of the cell 32, and the average fiber that has entered the cell 32. It is desirable that the long carbon fiber 1 has a size capable of rotating 360 ° in the inner circumferential direction of the cell 32 in the cell 32. Specifically, the diameter W of the circle N inscribed in the mouth shape of the cell 32 (specifically, the circle N inscribed in the opening peripheral edge 32d of the cell 32) is particularly limited as long as it is larger than the average fiber length of the carbon fibers 1. Although it is not a thing, it is desirable to set 1.2 times or more with respect to the average fiber length of the carbon fiber 1.

  4A, 5A, and 6A, the circle N inscribed in the mouth shape of the cell 32 is indicated by a two-dot chain line, and in FIG. 7A, the circle N inscribed in the mouth shape of the cell 32 is the opening peripheral edge 32d of the cell 32. Match.

  Thus, the shape of the cell 32 is cup-shaped, and the diameter W of the circle N inscribed in the mouth shape of the cell 32 is set to 1.2 times or more with respect to the average fiber length of the carbon fiber 1. Thus, when the coating liquid 5 adheres to the peripheral surface 31 a of the gravure roll 31, the carbon fiber 1 in the coating liquid 5 surely enters the cell 32. Then, the coating liquid 5 in the cell 32 is transferred and applied to the planned coating surface 10 a of the metal foil 10 as the gravure roll 31 rotates. As a result, the carbon fiber layer 11 is formed on the planned coating surface 10 a of the metal foil 10.

  The upper limit of the diameter W of the circle N inscribed in the mouth shape of the cell 32 is not limited and is, for example, 2500 μm.

  When the shape of the opening peripheral edge 32d of the cell 32 is a square shape (eg, lattice type 32A, pyramid type 32B), the diameter W of the circle N inscribed in the mouth shape of the cell 32 is the turtle shell type 32C. It is desirable that the size is larger than the case of the circular shape 32D, and it is particularly desirable that it is 1.5 times or more the average fiber length of the carbon fiber 1.

  The carbon fiber 1 can be used as long as it is a fibrous carbon particle, and specifically includes, for example, a PAN-based carbon fiber, a pitch-based carbon fiber, and a carbon nanofiber (eg, vapor-grown carbon fiber, carbon nanotube). One kind of carbon fiber selected from the group or two or more kinds of mixed carbon fibers are used.

  Of the PAN-based carbon fibers and pitch-based carbon fibers, it is particularly desirable to use pitch-based carbon fibers. The reason is that the thermal conductivity in the fiber axis direction of the pitch-based carbon fiber is larger than that of the PAN-based carbon fiber, and therefore, the composite material 20 having a higher thermal conductivity can be obtained.

  The length of the carbon fiber 1 is not limited. The upper limit of the average fiber length of the carbon fiber 1 is, for example, 1 mm, and the lower limit is, for example, 10 μm.

  The fiber diameter of the carbon fiber 1 is not limited, and the average fiber diameter of the carbon fiber 1 is, for example, 0.1 nm to 20 μm. When the carbon fiber 1 is a PAN-based carbon fiber or a pitch-based carbon fiber, the carbon fiber 1 is, for example, a chopped fiber or a milled fiber, and the average fiber diameter is, for example, 5 μm to 15 μm. When the carbon fiber 1 is a vapor growth carbon nanofiber, the average fiber diameter of the carbon fiber 1 is, for example, 0.1 nm to 20 μm.

  The binder 2 gives the carbon fiber 1 adhesion to the planned coating surface 10 a of the metal foil 10, whereby the carbon fiber 1 in the carbon fiber layer 11 falls off the planned coating surface 10 a of the metal foil 10. Is usually made of resin.

  Furthermore, it is desirable to use the binder 2 that disappears by sublimation or decomposition without carbonizing at a temperature of 200 ° C. to 450 ° C. in a non-oxidizing atmosphere. As such a binder 2, an acrylic resin, a polyethylene glycol resin, a butylene rubber resin, a phenol resin, a cellulose resin, or the like is preferably used. These binders 2 are generally solid at room temperature.

  The solvent 3 is desirably one that dissolves the binder 2 at room temperature, and water, alcohol solvents, hydrocarbon solvents, ester solvents, ether solvents, and the like are preferably used.

  The coating liquid 5 preferably contains the carbon fiber 1 and the binder 2 in a mass ratio of 75:25 to 99.5: 0.5. In this case, the carbon fiber 1 can be reliably attached to the coating intended surface 10a of the metal foil 10 in the step S1 of obtaining the coating foil 12, and the binder 2 is surely attached in the step S4a of removing the binder 2. It can be eliminated. It is particularly desirable that the coating liquid 5 contains the carbon fiber 1 and the binder 2 in a mass ratio of 80:20 to 99: 1.

In step S1 of obtaining the coating foil 12, the coating liquid 5 is applied to the planned coating surface 10a of the metal foil 10 so that the coating amount of the carbon fiber 1 contained in the carbon fiber layer 11 is 40 g / m ² or less. It is desirable to work. The reason is as follows.

That is, in the case where the coating liquid 5 is applied to the planned coating surface 10a of the metal foil 10 so that the coating amount of the carbon fibers 1 contained in the carbon fiber layer 11 is 40 g / m ² or less, the laminate In step S <b> 4 of sintering 15, the metal of the metal foil 10 sufficiently permeates substantially all of the voids in the carbon fiber layer 11, and the laminate 15 is reliably sintered. Thereby, the intensity | strength (mechanical strength etc.) of the composite material 20 can be raised reliably. Furthermore, in order to shorten the manufacturing time of the composite material 20, it is particularly desirable that the coating amount of the carbon fiber 1 contained in the carbon fiber layer 11 is 30 g / m ² or less.

  In addition, the coating liquid 5 is applied to the coating surface 10 a of the metal foil 10 so that the volume of the carbon fiber 1 is less than 50% of the total volume of the composite material 20 in the obtained composite material 20. In this way, the metal of the metal foil 10 can be surely permeated into the carbon fiber layer 11 in the step S4 of sintering the laminated body 15, and the laminated body 15 can be surely sintered firmly. it can.

  The metal foil 10 is not limited to the material as long as it can withstand coating. In particular, the metal foil 10 is desirably at least one of an aluminum foil and a copper foil. The reason is that the composite material 20 having high thermal conductivity can be reliably obtained.

  When the metal foil 10 is an aluminum foil, the material of the aluminum foil is not limited, and A1000 series, A3000 series, A6000 series, and the like are used. In general, the material of the aluminum foil is appropriately selected from a plurality of types of aluminum materials so that the physical properties (thermal conductivity, linear expansion coefficient, etc.) of the obtained composite material 20 are set to desired values. When the metal foil 10 is an aluminum foil, the metal matrix 21 of the composite 20 is an aluminum matrix. Therefore, the weight of the composite material 20 can be reduced, and the workability of the composite material 20 can be improved.

  When the metal foil 10 is a copper foil, the type and material of the copper foil are not limited, and an electrolytic copper foil, a rolled copper foil, and the like are used. In general, the material of the copper foil is appropriately selected from a plurality of types of copper materials so that the physical properties (thermal conductivity, linear expansion coefficient, etc.) of the obtained composite material 20 become desired set values.

  The thickness of the metal foil 10 is not limited, and the thickness of the metal foil 10 can be selected so that the physical properties of the obtained composite material 20 become a desired set value.

  Here, since the thinnest thickness of the commercially available metal foil (aluminum foil, copper foil) 10 is 6 μm, the lower limit of the thickness of the metal foil 10 is easily 6 μm. It is particularly desirable in that it is available. The upper limit of the thickness of the metal foil 10 is usually 100 μm, and particularly preferably about 50 μm.

  The width | variety of the metal foil 10 is not limited, It sets according to the use of the composite material 20, etc., for example, is set to 10 mm-1200 mm.

  Step S1a for removing the solvent 3 is performed by passing the coating foil 12 through the drying furnace 38 as shown in FIG. That is, when the coating foil 12 passes through the drying furnace 38, the carbon fiber layer 11 is heated and dried by the drying furnace 38, whereby the solvent 3 contained in the carbon fiber layer 11 is evaporated and removed from the carbon fiber layer 11. The Thereafter, the coating foil 12 is wound around the winding roll 37b.

  The conditions for removing the solvent 3 by the drying furnace 38 are not limited as long as the solvent 3 contained in the carbon fiber layer 11 can be removed from the carbon fiber layer 11 by evaporation. The drying time is 1 min to 120 min at 250 ° C.

  Furthermore, after removing the solvent 3, there may be a large gap in the carbon fiber layer 11, so the carbon fiber layer 11 is pressed in the thickness direction with a pressing roll (not shown). It is also possible to increase the bulk density of 11.

<Step S2 for obtaining material foil 13>
As shown in FIG. 10, in the step S2 of obtaining the material foil 13, the cutting device 40 is provided with the cutting foil 40 unwound from the winding roll 37b and supported by a die (not shown). The blade (punching punch) 41 is cut into a predetermined shape (punching). Thereby, a plurality of material foils 13 made of the cut pieces of the coating foil 12 are cut out from the coating foil 12.

  The arrow “D” in FIG. 10 indicates the direction of application of the coating liquid 5 to the coating application surface 10a of the metal foil 10 in the step S1 of obtaining the coating foil 12 as described above, and the arrow “E”. "Indicates the orientation direction of the carbon fibers 1 of the carbon fiber layer 11 of the coating foil 12 as described above.

  The orientation direction E of the carbon fiber 1 is generally determined by the coating direction D of the coating liquid 5, and the carbon fiber 1 is oriented in a predetermined direction with respect to the coating direction D of the coating liquid 5. In the present embodiment, the orientation direction E of the carbon fiber 1 coincides with the coating direction D of the coating liquid 5.

  In the figure, in order to make the coating direction D of the coating solution 5 in the coating foil 12 and the material foil 13 easy to understand, the coating direction D of the coating solution 5 is applied to the surface of the coating foil 12 and the material foil 13. A thin line is displayed. The same applies to the other figures (FIGS. 11, 17 and 19).

<Process S3 for Forming Laminate 15>
As shown in FIG. 11, in step S <b> 3 for forming the laminate 15, the laminate 15 of the material foil 13 is formed by laminating a plurality of material foils 13. The laminate 15 is used as a preform (sintered material).

  The number of stacked material foils 13 is not limited, and is set according to the desired thickness of the composite material 20, for example, 5 to 1000 sheets.

  The stacking order of the material foils 13 will be described below.

  In the step S3 of forming the laminated body 15, the coating direction 5 of the coating liquid 5 on at least one material foil 13 is applied to the plurality of material foils 13 with the coating liquid 5 on at least one other material foil 13. The layers are stacked so as to be different from the direction D. Desirably, a plurality of material foils 13 are laminated so that the coating direction D of the coating liquid 5 on the material foil 13 regularly changes in the thickness direction of the laminate 15 (that is, the vertical direction of the laminate 15).

  In this embodiment, in order to manufacture the composite material 20 shown in FIG. 1, a plurality of material foils 13 are laminated so that the coating directions D of the coating liquid 5 on the material foils 13 are alternately perpendicular. That is, a plurality of the material foils 13 are laminated so that the coating direction D of the coating liquid 5 on the material foil 13 changes 90 degrees clockwise (or counterclockwise) in plan view in the thickness direction of the laminate 15. To do.

  Thus, by laminating | stacking two or more raw material foil 13, the orientation of the planar direction of the carbon fiber 1 of the carbon fiber layer 11 of the whole laminated body is eased so that it may become small (it lose | disappears in detail). In other words, in the laminate 15, a plurality of material foils 13 are laminated in a regular arrangement so that the orientation in the planar direction of the carbon fibers 1 of the carbon fiber layer 11 of the entire laminate is relaxed.

<Step S4 of Sintering Laminate 15>
As shown in FIG. 12, in step S <b> 4 of sintering the laminated body 15, first, the laminated body 15 is disposed in a sintering chamber 51 of a sintering apparatus (joining apparatus) 50 such as a pressure heating sintering apparatus. Then, the laminated body 15 is heated at a predetermined sintering temperature while being pressed in the thickness direction (that is, the lamination direction of the material foil 13) in a predetermined sintering atmosphere by the sintering apparatus 50. The material foil 13 is sintered and integrated by sintering. As a result, the composite material 20 shown in FIG. 14 is obtained. A schematic cross-sectional view of the composite material 20 is shown in FIG.

  In this step S4, the laminate 15 is pressurized and heated as described above, so that the carbon fiber layer 11 is compressed in the thickness direction, and a part of the metal of the metal foil 10 penetrates into the carbon fiber layer 11. Then, the fine voids (eg, the gaps between the carbon fibers 1 in the carbon fiber layer 11) existing in the carbon fiber layer 11 are filled, and the voids substantially disappear. Thereby, the density of the obtained composite material 20 can be 95% or more of the theoretical density of the composite material 20.

  The theoretical density of the composite material 20 is the density of the composite material 20 when the composite material 20 is formed only of the metal of the metal foil 10 and the carbon fiber 1 and no voids are present inside the composite material 20. Means.

  Further, as described above, when a part of the metal of the metal foil 10 penetrates into the carbon fiber layer 11, the carbon fibers 1 in each carbon fiber layer 11 are dispersed in the metal matrix 21 of the composite material 20. That is, each carbon fiber layer 11 of the laminate 15 becomes each carbon fiber dispersion layer C of the composite material 20. Further, each metal foil 10 of the laminate 15 becomes each metal layer B of the composite material 20.

  As the sintering apparatus 50, a hot press apparatus (eg, vacuum hot press apparatus), a discharge plasma sintering apparatus, or the like is preferably used.

  The pressurization to the laminated body 15 is performed by, for example, pressing the laminated body 15 from both sides in the thickness direction with a pair of press punches 52 and 52 provided in the sintering apparatus 50.

  The sintering atmosphere is preferably a non-oxidizing atmosphere. The non-oxidizing atmosphere includes an inert gas atmosphere (eg, nitrogen gas atmosphere, argon gas atmosphere), a vacuum atmosphere, and the like.

  The sintering temperature means a temperature at which the laminate 15 is sintered. Specifically, the sintering temperature is set to a temperature equal to or lower than the melting point of the metal of the metal foil 10, and in particular, set to a temperature between the melting point of the metal of the metal foil 10 and a temperature about 50 ° C. lower than the melting point. It is desirable that the laminate 15 can be reliably sintered satisfactorily. When the metal foil 10 is, for example, an aluminum foil, the sintering temperature is desirably set in the range of 550 ° C to 620 ° C.

  The pressure applied to the stacked body 15 is not limited, and may be a pressure that lightly presses the stacked body 15. Furthermore, since the fluidity of the metal of the metal foil 10 may be improved when the laminate 15 is pressurized when heated to the laminate 15, the metal of the metal foil 10 is removed from the laminate 15 by the pressurization to the laminate 15. It is particularly desirable to pressurize with a pressing force that does not flow out, or pressurize the laminated body 15 in a mold (not shown) so that the metal of the metal foil 10 does not flow out of the laminated body 15.

  If the laminated body 15 is sintered in a state where a gap remains between the material foils 13 and 13 that overlap each other, the gap portion becomes an internal defect of the composite material 20. Therefore, in order to suppress the occurrence of this defect, it is desirable to pressurize the laminate 15 as a sintering atmosphere in a vacuum atmosphere and / or pressurize the laminate 15 in the mold.

  In the present embodiment, the step S4a for removing the binder 2 is performed by the sintering apparatus 50 in the course of heating the laminate 15 in the step S4 for sintering the laminate 15 from about room temperature as the initial temperature to the sintering temperature. . The binder removal step S4a in this case will be described below.

  FIG. 13 is a diagram (graph) illustrating an example of a temperature curve when the laminated body 15 is heated in the step S4 of sintering the laminated body 15.

  The temperature range of T1 to T2 (where T1 <T2) in the figure is a range in which the binder 2 contained in the carbon fiber layer 11 of the material foil 13 of the laminate 15 disappears due to sublimation or decomposition, Usually, it is 200 ° C to 450 ° C. T3 is a sintering temperature and is higher than T2 (that is, T3> T2).

  In the step S4 of sintering the laminated body 15, the temperature of the laminated body 15 during the heating of the laminated body 15 by the sintering apparatus 50 so that the temperature of the laminated body 15 rises from about room temperature to the sintering temperature T3 is T1. When within the range of T2, the binder 2 disappears by sublimation or decomposition and is removed from the laminate 15 (more specifically, the carbon fiber layer 11 of the material foil 13 of the laminate 15).

  The time Δt during which the temperature of the laminate 15 is within the temperature range of T1 to T2 is not limited as long as the binder 2 can be removed from the laminate 15, and the temperature of the laminate 15 is increased by the sintering device 50. It is set according to the temperature rate, the total amount of the binder 2 contained in the laminate 15, the thickness of the laminate 15 (eg, the number of laminated material foils 13), the sintering atmosphere, etc., usually 10 min or more Set to

  Further, when the temperature of the laminated body 15 is within the temperature range of T1 to T2, the time Δt is lengthened by temporarily stopping the temperature increase or slowing the temperature increase rate, thereby reliably removing the binder 2. It is also possible to do so.

  Thus, the number of manufacturing steps of the composite material 20 is reduced by performing the step S4a for removing the binder 2 in the course of heating the laminate 15 in the step S4 for sintering the laminate 15 to the sintering temperature T3. Therefore, the composite material 20 can be easily manufactured.

  In addition, this invention does not exclude that process S4a which removes the binder 2 is performed independently from process S4 which sinters the laminated body 15 with the sintering apparatus 50. FIG.

  In this case, the step S4a for removing the binder 2 is desirably performed after the step S3 for forming the laminated body 15 and before the step S4 for sintering the laminated body 15. The reason is that it is possible to reliably suppress the carbon fibers 1 in the carbon fiber layer 11 from dropping from the planned coating surface 10 a of the metal foil 10 when the laminate 15 is formed. Furthermore, in this case, after performing the step S4a for removing the binder 2 and before performing the step S4 for sintering the laminated body 15, the laminated body 15 is placed in a non-oxidizing atmosphere or / And it is desirable to set the temperature of the laminated body 15 to 300 degrees C or less. The reason is that the oxidation consumption of the carbon fiber 1 can be reliably suppressed, and the oxidation of the aluminum foil can be reliably suppressed when the metal foil 10 is an aluminum foil.

  The composite material 20 and its manufacturing method of the present embodiment have the following advantages.

  In the step S3 of forming the laminated body 15, the coating direction 5 of the coating liquid 5 on at least one material foil 13 is applied to the plurality of material foils 13 with the coating liquid 5 on at least one other material foil 13. The layers are stacked so as to be different from the direction D. Thereby, the orientation of the carbon fiber 1 in the planar direction of the carbon fiber layer 11 of the entire laminate is relaxed. And the anisotropy of the physical property (Example: thermal conductivity, linear expansion coefficient) of the planar direction of the whole composite material can be relieved by sintering this laminated body 15. FIG.

  If this process S is explained in full detail, since the material foil 13 is laminated | stacked so that the coating direction D of the coating liquid 5 in the material foil 13 may change regularly in the thickness direction of the laminated body 15, it is laminated. The orientation in the plane direction of the carbon fibers 1 of the carbon fiber layer 11 of the whole body is reliably relaxed. And by sintering this laminated body 15, the anisotropy of the physical property of the whole composite material of the planar direction can be relieve | moderated reliably.

  In addition, in the present embodiment, as described above, the coating apparatus for applying the coating liquid 5 to the planned coating surface 10 a of the metal foil 10 is the gravure coating apparatus 30, and the gravure of the gravure coating apparatus 30 The shape of the cell 32 of the roll 31 is cup-shaped, and the diameter W of the circle N inscribed in the mouth shape of the cell 22 is set to 1.2 times or more with respect to the average fiber length of the carbon fiber 1. Thereby, the carbon fiber layer 11 can be formed on the application surface 10a of the metal foil 10 so that the orientation direction of the carbon fibers 1 in the application surface 10a of the metal foil 10 becomes relatively random. Therefore, the orientation in the plane direction of the carbon fibers 1 of the carbon fiber layer 11 of the material foil 13 is greatly relaxed.

  By laminating a plurality of such material foils 13 so that the coating direction D of the coating liquid 5 on the material foils 13 regularly changes in the thickness direction of the laminate 15 as described above, the entire laminate is obtained. The orientation of the carbon fibers 1 of the carbon fiber layer 11 in the planar direction is greatly relaxed. And by sintering this laminated body 15, the anisotropy of the physical property of the whole composite material of the plane direction can be remarkably eased.

  Here, although it is desirable for the reason described above that the coating apparatus is the gravure coating apparatus 30, in the present invention, the coating apparatus is not limited to being the gravure coating apparatus 30, in addition, A roll coater, a three roll coater (for example, offset type), a die coater, a knife coater, a curtain coater, a bar coater, a doctor blade coater, a spray coater, etc. may be used. That is, in the present invention, in the step S1 of obtaining the coating foil 12, it is desirable to apply the coating liquid 5 to the planned coating surface 10a of the metal foil 10 by the gravure coating method. Coating may be performed by a coating method such as a three-roll coating method (for example, an offset type), a die coating method, a knife coating method, a curtain coating method, a bar coating method, a doctor blade coating method, or a spray coating method.

  As described above, the composite material 20 of the present embodiment has high reliability against temperature changes such as a cooling cycle because the anisotropy of the physical properties in the planar direction of the entire composite material is relaxed. Therefore, the composite material 20 can be suitably used as a material of at least one constituent layer among the plurality of cooler constituent layers constituting the cooler 60 shown in FIG.

  The cooler 60 cools a heating element 66 (indicated by a two-dot chain line) as an object to be cooled, and includes a wiring layer 61, an insulating layer 62, a buffer layer 63, and a cooling layer 64 as a plurality of cooler constituent layers. It has. Then, in order from top to bottom, these layers 61 to 64 are joined and integrated by a predetermined joining means such as brazing in a state where the wiring layer 61, the insulating layer 62, the buffer layer 63, and the cooling layer 64 are laminated. Thus, the cooler 60 is formed.

  Examples of the heating element 66 include electronic elements such as power module elements. When the heating element 66 is a power module element, the cooler 60 is a power module cooler. The power module is used for vehicles such as a hybrid car (HEV), an electric vehicle (EV), and a train, or used in an energy field such as wind power generation and solar power generation.

  A heating element 66 is bonded to the mounting surface 61a formed from the upper surface of the wiring layer 61 by a predetermined bonding means such as soldering.

  The insulating layer 62 has electrical insulation and is usually made of ceramic.

  The buffer layer 63 is a layer for relaxing stress such as thermal stress generated in the cooler 60.

  The cooling layer 64 is a layer for dissipating the heat of the heat generating element 66 to cool the heat generating element 66, and is made of, for example, a cooling member (including a heat radiating member) and has a plurality of heat radiating fins 64a.

  In detail, in the cooler 60 described above, at least one selected from the group consisting of constituent layers (that is, the wiring layer 61, the buffer layer 63, and the cooling layer 64) excluding the insulating layer 62 among the plurality of constituent layers described above. One is made of the composite material of this embodiment. Therefore, the cooler 60 has high reliability (eg, high bonding reliability) with respect to temperature changes such as a cooling / heating cycle.

  In this invention, the arrangement | sequence of the lamination direction of the raw material foil 13 in process S3 which forms the laminated body 15 is not limited to what was shown to the said embodiment. Some examples of the arrangement of the material foils 13 are shown in FIG. FIG. 17 shows the types of material foils 13 denoted by reference numerals “A1” to “A4” in FIG. The present invention is not limited to the arrangement of the material foils 13 shown in FIG.

  An arrow D in FIGS. 17A to 17D indicates the coating direction of the coating liquid 5 in each material foil 13. The orientation direction E of the carbon fibers 1 of the carbon fiber layer 11 of each material foil 13 is determined by the coating direction D of the coating liquid 5, for example, coincides with the coating direction D of the coating liquid 5. .

  The coating direction D of the coating solution 5 on the material foil 13 of the type “A1” shown in FIG. 17A and the coating of the coating solution 5 on the material foil 13 of the type “A2” shown in FIG. The angle formed with the process direction D is 90 °. The coating direction D of the coating solution 5 on the material foil 13 of the type “A1” shown in FIG. 17A and the application of the coating solution 5 on the material foil 13 of the type “A3” shown in FIG. The angle formed with the process direction D is 45 °. The coating direction D of the coating liquid 5 on the material foil 13 of the type “A3” shown in FIG. 17C and the application of the coating liquid 5 on the material foil 13 of the type “A4” shown in FIG. The angle formed with the process direction D is 90 °.

  The unit of arrangement in the stacking direction of the material foils 13 of the laminate 15 shown in FIG. 16A is basically the same as that of the laminate 15 shown in FIG. 1 of the above embodiment. That is, the unit of arrangement of the material foils 13 of the laminate 15 in FIG. 16A is a unit of A1 / A2. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber layer 11 of the entire array unit is relaxed. And in this laminated body 15, the raw material foil 13 is laminated | stacked in accordance with the lamination rule that this arrangement unit is repeated over the whole thickness direction of the laminated body 15. FIG.

  The unit of arrangement in the stacking direction of the material foil 13 of the laminate 15 shown in FIG. 16B is a unit of A1 / A1 / A2 / A2. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber layer 11 of the entire array unit is relaxed. And in this laminated body 15, the raw material foil 13 is laminated | stacked in accordance with the lamination rule that this arrangement unit is repeated over the whole thickness direction of the laminated body 15. FIG.

  The unit of arrangement in the stacking direction of the material foil 13 of the laminate 15 shown in FIG. 16C is a unit of A1 / A2 / A3 / A4. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber layer 11 of the entire array unit is relaxed. And in this laminated body 15, the raw material foil 13 is laminated | stacked in accordance with the lamination rule that this arrangement unit is repeated over the whole thickness direction of the laminated body 15. FIG.

  The unit of arrangement in the stacking direction of the material foils 13 of the laminate 15 shown in FIG. 16D is a unit of A1 / A3 / A2 / A4. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber layer 11 of the entire array unit is relaxed. And in this laminated body 15, the raw material foil 13 is laminated | stacked in accordance with the lamination rule that this arrangement unit is repeated over the whole thickness direction of the laminated body 15. FIG.

  The unit of arrangement in the stacking direction of the material foil 13 of the laminate 15 shown in FIG. 16E is a unit of A1 / A3 / A2 / A4 / A4 / A2 / A3 / A1. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber layer 11 of the entire array unit is relaxed. And in this laminated body 15, the raw material foil 13 is laminated | stacked in accordance with the lamination rule that this arrangement unit is repeated over the whole thickness direction of the laminated body 15. FIG.

  Therefore, in any of the laminates 15 of FIGS. 16A to 16E, the material foil 13 has a coating direction D of the coating liquid 5 in the material foil 13 in the thickness direction of the laminate 15. A plurality of layers are stacked so as to change in accordance with a predetermined stacking rule over the entire thickness direction. Thereby, the orientation of the carbon fiber 1 in the planar direction of the carbon fiber layer 11 of the entire laminate is relaxed.

  FIG. 18 is a schematic diagram illustrating some examples of the arrangement of the carbon fiber dispersion layers C of the composite material 20. The present invention is not limited to the arrangement of the carbon fiber dispersion layers C shown in FIG.

  Reference numerals “C 1”, “C 2”, “C 3”, “C 4”, “C 5”, and “C 6” in the figure indicate the types of the carbon fiber dispersion layers C in the composite material 20. The orientation directions of the carbon fibers 1 of the carbon fiber dispersion layers C of the types “C1” to “C6” are different from each other. In the figure, in order to facilitate understanding of the arrangement of the carbon fiber dispersion layers C of the composite material 20, a metal layer (see FIG. 1) disposed between the carbon fiber dispersion layers C and C adjacent in the thickness direction of the composite material 20. Reference (reference “B”) is omitted.

  The unit of arrangement in the stacking direction of the carbon fiber dispersion layer C of the composite material 20 shown in FIG. 18A is basically the same as that of the composite material 20 shown in FIG. That is, the unit of arrangement of the carbon fiber dispersion layer C of the composite material 20 in FIG. 18A is a unit of C1 / C2. The orientation in the plane direction of the carbon fibers 1 of the carbon fiber dispersion layer C of the entire array unit is relaxed. In the composite material 20, the carbon fiber dispersion layers C are arranged in accordance with a lamination rule that the arrangement unit is repeated over the entire thickness direction of the composite material 20.

  The unit of arrangement in the stacking direction of the carbon fiber dispersion layer C of the composite material 20 shown in FIG. 18B is a unit of C1 / C1 / C2 / C2. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber dispersion layer C of the entire array unit is relaxed. In the composite material 20, the carbon fiber dispersion layers C are arranged in accordance with a lamination rule that the arrangement unit is repeated over the entire thickness direction of the composite material 20.

  The unit of the arrangement in the stacking direction of the carbon fiber dispersion layer C of the composite material 20 shown in FIG. 18C is a unit of C1 / C2 / C3. The orientation in the plane direction of the carbon fibers 1 of the carbon fiber dispersion layer C of the entire array unit is relaxed. In the composite material 20, the carbon fiber dispersion layers C are arranged in accordance with a lamination rule that the arrangement unit is repeated over the entire thickness direction of the composite material 20.

  The unit of the arrangement in the stacking direction of the carbon fiber dispersion layer C of the composite material 20 shown in FIG. 18D is a unit of C1 / C2 / C3 / C3 / C2 / C1. The orientation in the planar direction of the carbon fibers 1 of the carbon fiber dispersion layer C of the entire array unit is relaxed. In the composite material 20, the carbon fiber dispersion layers C are arranged in accordance with a lamination rule that the arrangement unit is repeated over the entire thickness direction of the composite material 20.

  The unit of the arrangement in the stacking direction of the carbon fiber dispersion layer C of the composite material 20 shown in FIG. 18E is a unit of C1 / C2 / C3 / C4 / C5 / C6. The orientation in the plane direction of the carbon fibers 1 of the carbon fiber dispersion layer C of the entire array unit is relaxed. In the composite material 20, the carbon fiber dispersion layers C are arranged in accordance with a lamination rule that the arrangement unit is repeated over the entire thickness direction of the composite material 20.

  Therefore, in any of the composite materials 20 in FIGS. 18A to 18E, the carbon fiber dispersion layer C is combined with the orientation direction E of the carbon fibers 1 of the carbon fiber dispersion layer C in the thickness direction of the composite material 20. It arrange | positions so that it may change according to a predetermined | prescribed lamination rule over the whole thickness direction of the material 20. As shown in FIG. Thereby, the orientation in the plane direction of the carbon fibers 1 of the carbon fiber dispersion layer C of the entire composite material is relaxed.

  Moreover, in the manufacturing method of the composite material which concerns on this invention, process S3 which forms a laminated body, and process S4 which sinters a laminated body may be performed as follows.

  That is, as shown in FIG. 19, in the step S3 of forming a laminated body, a plurality of material foils 13 are laminated to form a first laminated body 15a, and then the first laminated body 15a is left in a laminated state with its thickness. At least one second laminated body 15b may be obtained by cutting in a predetermined shape by a cutting device (not shown) in the vertical direction. And in process S4 which sinters a laminated body, it heats and sinters, pressing the 2nd laminated body 15b as a laminated body in the thickness direction, Thereby, material foil 13 which comprises the 2nd laminated body 15b Sintered and integrated. In the present embodiment, the number of the second stacked bodies 15b obtained by cutting the first stacked body 15a is plural, and for example, four in detail.

  In the first laminate 15a, the plurality of material foils 13 are coated with the coating liquid in at least one material foil 13 whose coating direction (D, see FIG. 11) is at least one material foil 13. It is laminated so as to be different from the working direction (D). Desirably, the 1st laminated body 15a is laminated | stacked so that the coating direction (D) of the coating liquid in the raw material foil 13 may change regularly in the thickness direction of the 1st laminated body 15a. The stacking rule of the first stacked body 15a is, for example, the same as the stacking rule shown in the above embodiment.

  More specifically, the second laminated body 15b is obtained by punching the first laminated body 15a into a predetermined shape in the thickness direction with a punching device (not shown) as a cutting device in the thickness direction. It is. As the punching device, a punching press device provided with a punching punch or the like is used. The second laminated body 15b is formed in a substantially columnar shape (in detail, a substantially cylindrical shape). The cross-sectional area in the planar direction of the second stacked body 15b is smaller than that of the first stacked body 15a.

  The diameter of the 2nd laminated body 15b (namely, the diameter of the raw material foil 13 which comprises the 2nd laminated body 15b) is not limited, For example, it is 20-200 mm.

  Thus, by cutting (punching) the first stacked body 15a in the thickness direction to obtain the second stacked body 15b, a stacked body having a small cross-sectional area in the plane direction can be easily formed. And the composite material with a small cross-sectional area of a plane direction can be easily obtained by sintering this 2nd laminated body 15b.

  Although several embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  In this invention, in process S3 which forms the laminated body 15, as the raw material foil, the carbon fiber layer 11 is formed on the coating scheduled surface 10a of the metal foil 10, and the raw material foil 13 and the carbon particle layer other than the carbon fiber layer are provided. The laminated body 15 may be formed using the material foil formed on the surface 10a to be coated of the metal foil 10.

  As the carbon particles in the carbon particle layer other than the carbon fiber layer, for example, at least one carbon particle selected from the group consisting of natural graphite particles, artificial graphite particles, and pyrolytic graphite particles is used. The average length in the longest axial direction of these carbon particles is not limited, and the upper limit is, for example, 1 mm, and the lower limit is, for example, 10 μm.

  In the present invention, it is not excluded that the carbon fiber layer 11 also contains at least one carbon particle selected from the group consisting of natural graphite particles, artificial graphite particles, and pyrolytic graphite particles.

  In the present invention, the metal foil 10 has a surface on one side in the thickness direction and a surface on the other side as the surfaces to be coated, and the coating foil 12 (material foil 13) is In addition, a carbon fiber particle layer may be formed on one application planned surface of the metal foil 10 and a carbon particle layer other than the carbon fiber layer may be formed on the other application planned surface of the metal foil 10. .

  Further, in the present invention, the gravure coating apparatus 30 is particularly preferably a direct gravure coating apparatus as shown in the above embodiment, but in addition, for example, an offset gravure coating apparatus (eg, offset gravure coater). May be.

  In addition, the composite material according to the present invention is not limited to being used as a material of the constituent layer of the power module cooler 60 as shown in the above embodiment, but in addition to the constituent members of the lighting equipment. It can also be used as a material, a component material of a portable / mobile terminal, a material of a heat spreader, a material of a heat pipe, a material of a battery module, and the like.

  INDUSTRIAL APPLICABILITY The present invention can be used for a metal-carbon particle composite material including a metal matrix and carbon particles dispersed in the metal matrix, a manufacturing method thereof, and a cooler.

1: Carbon fiber (carbon particles)
5: Coating liquid 10: Metal foil 10a: Planned coating surface 11: Carbon fiber layer (carbon particle layer)
12: coating foil 13: material foil 15: laminate 15a: first laminate 15b: second laminate 20: metal-carbon particle composite material 21: metal matrix B: metal layer C: carbon fiber dispersion layer (carbon particles Dispersion layer)
30: Coating apparatus D: Coating direction of coating liquid E: Orientation direction of carbon fiber

Claims (8)

A metal layer composed of a metal matrix and a carbon particle dispersion layer in which carbon particles are dispersed in the metal matrix are joined and integrated in a state where a plurality of layers are alternately laminated,
The metal-carbon in which the orientation direction of the carbon particles of at least one of the plurality of carbon particle dispersion layers is different from the orientation direction of the carbon particles of at least one other carbon particle dispersion layer. Particle composite material.   The metal layer and the carbon particle dispersion layer are arranged in a state where a plurality of layers are alternately laminated so that the orientation direction of the carbon particles of the carbon particle dispersion layer regularly changes in the thickness direction of the composite material. Item 4. The metal-carbon particle composite material according to Item 1.   The metal-carbon particle composite material according to claim 1 or 2, wherein the metal matrix is an aluminum matrix. A cooler for cooling the heating element,
A plurality of cooler constituent layers joined and integrated in a laminated manner,
A cooler in which at least one of the plurality of constituent layers is made of the metal-carbon particle composite material according to claim 1. A step of obtaining a coating foil in which a carbon particle layer is formed on the planned coating surface of the metal foil by coating a coating liquid containing carbon particles on the planned coating surface of the metal foil;
Cutting the coating foil to obtain a material foil;
Forming a laminate by laminating a plurality of the material foils;
A step of sintering the laminate,
In the step of forming the laminate, the coating direction of the coating liquid in at least one of the material foils is the coating direction of the coating liquid in the at least one other material foil of the plurality of material foils. A method for producing a metal-carbon particle composite material that is laminated differently.   6. The step of forming the laminate, wherein a plurality of the material foils are laminated so that a coating direction of the coating liquid in the material foils regularly changes in a thickness direction of the laminate. A method for producing a metal-carbon particle composite material. In the step of forming the laminated body, a plurality of the material foils are laminated to form a first laminated body, and then the first laminated body is cut to obtain a second laminated body,
The method for producing a metal-carbon particle composite material according to claim 5 or 6, wherein, in the step of sintering the laminate, the second laminate as the laminate is sintered.   The said metal foil is aluminum foil, The manufacturing method of the metal-carbon particle composite material in any one of Claims 5-7.

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