JP7331539B2 - Parts for heat diffusion - Google Patents

Description

TECHNICAL FIELD The present invention relates to a composite metal plate for heat diffusion and a component for heat diffusion, and for example, a composite metal plate for heat diffusion that can be applied to applications whose main purpose is to dissipate the heat of a heat generating element to the outside of the heat generating element. , a heat diffusion composite metal plate having a total thickness of 500 μm or less, in which copper layers and stainless steel layers are alternately bonded, and a heat diffusion component using this heat diffusion composite metal plate. In the present invention, a composite metal plate with a small overall thickness of 100 μm or less is particularly referred to as a “composite metal foil”, and a composite metal plate with a smaller overall thickness of 50 μm or less is particularly referred to as a “composite metal thin foil”. I may call

Conventionally, a composite metal plate in which a copper plate (copper layer) and a stainless steel plate (stainless steel layer) are bonded together is used in thermal diffusion applications whose main purpose is to dissipate the heat of the heating element to the outside of the heating element. there is For example, Patent Literature 1 discloses a plate heat exchanger in which a plurality of heat transfer plates each having a continuous uneven surface are laminated. This heat transfer plate is a composite metal plate for heat diffusion (clad plate material) having a three-layer structure in which copper plates are bonded to both front and back surfaces of a stainless steel plate. A component made by laminating a plurality of heat transfer plates, which is configured using this composite metal plate, is a heat diffusion component that can dissipate heat from a heat source by utilizing heat conduction to the heat transfer plate. .

Further, for example, Patent Literature 2 discloses a vapor chamber configured by a flat plate-like container (housing) integrally formed by joining a pair of opposing plate materials. A pair of plate materials that constitute the housing of this vapor chamber are composite metal plates for heat diffusion (clad plate materials) having a two-layer structure in which a copper plate and a stainless steel plate are joined together. The casing of this vapor chamber has a pressure-reduced sealing (sealed) working fluid such as water, CFC substitute, or alcohol capable of transporting heat in the form of latent heat in its internal space. The housing of the vapor chamber is a heat diffusion component that can release the heat of the heat source to the outside using heat conduction to the plate material and the working fluid. It is said that the composite metal plate for heat diffusion may be a composite metal plate (clad plate material) having a three-layer structure in which the front and back surfaces of a stainless steel plate are sandwiched between copper plates.

JP-A-2005-134073 JP 2016-188734 A

The composite metal plate for thermal diffusion disclosed in Patent Document 1 is bent to form an uneven surface and brazed in an electric furnace. In addition, a pair of heat diffusion composite metal plates that constitute the housing of the vapor chamber disclosed in Patent Document 2 are bent to form the housing, and are welded or welded together to prevent leakage of the working fluid. It is considered that they are joined by brazing or the like. Any composite metal plate for heat diffusion has appropriate heat conduction characteristics for heat diffusion, and unlike a metal plate (single plate) made of a single metal material, it consists of a copper plate (copper layer) and stainless steel. It has appropriate mechanical properties that enable plastic deformation without peeling from the steel plate (stainless steel layer), and is 700 ° C. or higher by brazing (silver brazing, etc.) or 1000 ° C. or higher (copper brazing, Nickel braze, etc.) must have suitable heat resistance properties that can be applied to high temperatures or partial melting by welding.

However, Patent Document 1 and Patent Document 2 do not disclose an appropriate composition of the copper layer (copper plate) and stainless steel layer (stainless steel plate) that constitute the composite metal plate for heat diffusion, and the total thickness of the composite metal plate thickness, the thicknesses of the copper layer and the stainless steel layer, and the thickness ratio between the copper layer and the stainless steel layer are not disclosed. Since the specific information considered necessary for such practical use was not disclosed, the composite metal plate for heat diffusion constituting the heat transfer plate disclosed in Patent Document 1 and the vapor chamber housing disclosed in Patent Document 2 Not limited to a pair of composite metal plates for heat diffusion constituting a body, the necessary properties of the composite metal plate for heat diffusion suitable for the desired application, especially the balance between the mechanical properties and the heat conduction properties of the composite metal plate for heat diffusion And the directional characteristics of the heat conduction properties could not be found appropriately and easily.

One object of the present invention is to provide a heat diffusion composite metal plate having a total thickness of 500 μm or less, in which copper layers and stainless steel layers are alternately bonded, and for example, the heat of a heat generating element is transferred to the outside of the heat generating element. On the required characteristics of composite metal plates for heat diffusion that can be applied to applications where the main purpose is to release heat, especially the balance between mechanical characteristics and heat conduction characteristics, and the directional characteristics of heat conduction characteristics (ratio of thermal conductivity) , can be found appropriately and easily, can easily provide a composite metal plate for heat diffusion suitable for various uses, and can easily provide a heat diffusion part using this composite metal plate for heat diffusion. It is to make

In the course of studying the necessary properties of conventional composite metal plates for heat diffusion (clad plate materials) that are suitable for the desired application of heat diffusion, the present inventors have found that, in particular, the combination of mechanical properties and thermal conductivity properties of composite metal plates With regard to balance and directional characteristics of thermal conductivity characteristics (ratio of thermal conductivity), the inventors have found means for solving the above-described problems, and arrived at the present invention.

A heat diffusion component according to the present invention is a housing-shaped heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer, and has a total thickness of is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the thickness of the stainless steel layer is is Ts and the thickness of the second copper layer is Tc2, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the thermal conductivity in the plane direction of the composite metal plate is The composite metal plate for heat diffusion, wherein the ratio of the thermal conductivity obtained by Kx/Kz is 4.4 or more and 6.8 or less, where Kx is the thermal conductivity in the thickness direction of the composite metal plate, and Kz is the thermal conductivity in the thickness direction of the composite metal plate. a first member configured by, a second member configured having a copper plate portion, and an internal space, a bent portion on one end side of the first member and a plane on the one end side of the second member The internal space is airtightly sealed by joining the bent portion on the other end side of the first member and the flat portion on the other end side of the second member.

A heat diffusion component according to the present invention is a housing-shaped heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer, and has a total thickness of is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the thickness of the stainless steel layer is is Ts and the thickness of the second copper layer is Tc2, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the thermal conductivity in the plane direction of the composite metal plate is The composite metal plate for heat diffusion, wherein the ratio of the thermal conductivity obtained by Kx/Kz is 4.4 or more and 6.8 or less, where Kx is the thermal conductivity in the thickness direction of the composite metal plate, and Kz is the thermal conductivity in the thickness direction of the composite metal plate. , a second member made of the composite metal plate for heat diffusion, and an internal space, a bending portion on one end side of the first member and one end side of the second member and the flat portion of the first member are joined together, and the bent portion on the other end side of the first member and the flat portion on the other end side of the second member are joined to hermetically seal the internal space. Moreover, it is preferable that the second member has a porous copper layer adjacent to the copper plate portion on the inner space side.

A heat diffusion component according to the present invention is a housing-shaped heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer, and has a total thickness of is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the thickness of the stainless steel layer is is Ts and the thickness of the second copper layer is Tc2, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the thermal conductivity in the plane direction of the composite metal plate is The composite metal plate for heat diffusion, wherein the ratio of the thermal conductivity obtained by Kx/Kz is 4.4 or more and 6.8 or less, where Kx is the thermal conductivity in the thickness direction of the composite metal plate, and Kz is the thermal conductivity in the thickness direction of the composite metal plate. a first member configured by, a second member configured having a copper plate portion, and an internal space, a bent portion on one end side of the first member and an end face on the one end side of the second member The internal space is airtightly sealed by joining the bent portion on the other end side of the first member and the end face portion on the other end side of the second member. Moreover, it is preferable to have a porous copper layer adjacent to the copper plate portion on the inner space side of the second member.

A heat diffusion component according to the present invention is a housing-shaped heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer, and has a total thickness of is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the thickness of the stainless steel layer is is Ts and the thickness of the second copper layer is Tc2, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the thermal conductivity in the plane direction of the composite metal plate is The composite metal plate for heat diffusion, wherein the ratio of the thermal conductivity obtained by Kx/Kz is 4.4 or more and 6.8 or less, where Kx is the thermal conductivity in the thickness direction of the composite metal plate, and Kz is the thermal conductivity in the thickness direction of the composite metal plate. a first member configured by, a second member configured having a copper plate portion, and an internal space, a bent portion on one end side of the first member and a plane on the one end side of the second member The internal space is airtightly sealed by joining the bent portion on the other end side of the first member and the flat portion on the other end side of the second member. Moreover, it is preferable to have a porous copper layer adjacent to the copper plate portion on the inner space side of the second member.

The Kx may be 340 W/(m·K) or less, and the Kz may be 20 W/(m·K) or more.

The first copper layer and the second copper layer are composed of pure copper containing 99% by mass or more of Cu, or composed of a copper alloy having a higher thermal conductivity than the stainless steel that constitutes the stainless steel layer. is preferred.

The stainless steel layer is, by mass%, 10.5% or more and 30% or less of Cr, 0.6% or more and 25% or less of Ni, 0.20% or less of C, and the balance of Fe and unavoidable impurities. It is preferably made of steel.

According to the present invention, a heat diffusion composite metal plate having a total thickness of 500 μm or less, in which copper layers and stainless steel layers are alternately bonded, is configured to release the heat of a heat generating element to the outside of the heat generating element, for example. Necessary properties of a composite metal plate for heat diffusion that can be applied to applications whose main purpose is to: . As a result, it becomes possible to easily provide a composite metal plate for heat diffusion suitable for various uses, and to easily provide a heat diffusion component using this composite metal plate for heat diffusion.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram schematically showing the layer structure of one embodiment of the composite metal plate for heat diffusion according to the present invention; 1 is a diagram schematically showing the configuration (first configuration example) of an embodiment of a heat diffusion component according to the first aspect of the present invention; FIG. FIG. 4 is a diagram schematically showing the configuration (second configuration example) of one embodiment of the heat diffusion component according to the second aspect of the present invention; FIG. 10 is a diagram schematically showing the configuration (modification of the second configuration example) of one embodiment of the heat diffusion component according to the second aspect of the present invention; FIG. 10 is a diagram schematically showing the configuration (third configuration example) of one embodiment of the heat diffusion component according to the third aspect of the present invention; FIG. 10 is a diagram schematically showing the configuration of one embodiment of the heat diffusion component (modification of the third configuration example) according to the third aspect of the present invention; FIG. 10 is a diagram schematically showing the configuration (fourth configuration example) of one embodiment of the heat diffusion component according to the fourth aspect of the present invention; FIG. 12 is a diagram schematically showing the configuration of one embodiment of the component for heat diffusion according to the fourth aspect of the present invention (modification of the fourth configuration example); FIG. 12 is a diagram schematically showing the configuration (fifth configuration example) of one embodiment of the heat diffusion component according to the fifth aspect of the present invention; FIG. 12 is a diagram schematically showing the configuration of one embodiment of the heat diffusion component (modification of the fifth configuration example) according to the fifth aspect of the present invention; Regarding one embodiment of the composite metal plate for heat diffusion according to the present invention, the thickness ratio (Ts / Tc) of the thickness of the copper layer (Tc = Tc1 + Tc2) and the thickness of the stainless steel layer (TS), and the planar direction (rolling 2 is a diagram (graph) showing the relationship between the direction (X direction) and the thermal conductivity (Kx). FIG. Regarding one embodiment of the composite metal plate for heat diffusion according to the present invention, the thickness ratio (Ts/Tc) of the thickness of the copper layer (Tc = Tc1 + Tc2) and the thickness of the stainless steel layer (Ts), and the cross-sectional direction (thickness FIG. 10 is a diagram (graph) showing the relationship with the thermal conductivity (Kz) in the longitudinal direction (Z direction). 1 is a diagram (graph) showing a relationship between a thickness ratio (Ts/Tc) and a thermal conductivity ratio (Kx/Kz) for one embodiment of the composite metal plate for heat diffusion according to the present invention. FIG.

A composite metal plate for heat diffusion according to the present invention is a composite metal plate having an overall thickness of 500 μm or less, in which a first copper layer, a stainless steel layer, and a second copper layer are joined in this order, When the thickness of the first copper layer is Tc1, the thickness of the stainless steel layer is Ts, and the thickness of the second copper layer is Tc2, the thickness ratio obtained by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less. 6. Where Kx is the thermal conductivity in the plane direction of the composite metal plate and Kz is the thermal conductivity in the thickness direction of the composite metal plate, the ratio of the thermal conductivity obtained by Kx/Kz is 4.4 or more. 8 or less. As a result, the necessary properties of the composite metal plate for heat diffusion suitable for the desired application of heat diffusion, particularly the balance between the mechanical properties and the heat conduction properties of the composite metal plate for heat diffusion, and the directional property of the heat conduction property (heat The composite metal plate for heat diffusion has a structure that can be found appropriately and easily with respect to the conductivity ratio), that is, the anisotropy of the thermal conductivity characteristics.

Hereinafter, one embodiment of the composite metal plate for heat diffusion according to the present invention and an example of the configuration of a heat diffusion component using the composite metal plate for heat diffusion according to the present invention will be described with reference to the drawings as appropriate. .

In describing the composite metal plate for heat diffusion and the component for heat diffusion according to the present invention, the following notations are used.
・Composite metal plate for heat diffusion: Composite metal plate ・First copper layer and/or second copper layer: Copper layer (when the first copper layer and the second copper layer are not distinguished)
・Joining between layers :/
・Layer structure of composite metal plate: copper layer/stainless steel layer/copper layer ・Overall thickness of composite metal plate: T
・Thickness of first copper layer: Tc1
・Thickness of second copper layer: Tc2
・Total thickness of the first copper layer and the second copper layer: Tc (=Tc1+Tc2)
・Thickness of stainless steel layer: Ts
・Planar direction of composite metal plate (representative): X direction (corresponding to rolling direction)
・Planar direction of composite metal plate: Y direction (corresponding to rolling width direction)
・Thickness direction of composite metal sheet: Z direction (corresponding to rolled sheet thickness direction)
・Thermal conductivity of the composite metal plate in the X direction: Kx
・Thermal conductivity of the composite metal plate in the Y direction: Ky
・Thermal conductivity of the composite metal plate in the Z direction: Kz
・Ratio of thermal conductivity of composite metal plate: AIS (= Kx/Kz)

In the present invention, the "AIS" is introduced as an index representing the anisotropy of thermal conductivity in the X direction and Z direction of the composite metal plate for heat diffusion. This AIS is obtained by dividing Kx (W/(mK)) of the composite metal plate measured in a predetermined temperature range by Kz (W/(mK)) measured in the same temperature range. . In addition, when the composite metal plate has isotropy in the X direction and the Y direction, Kx and Ky have approximately the same value. For example, in the case of a metal plate made of a single material, the AIS is about 1 because it is generally isotropic. On the other hand, a metal with a low thermal conductivity (for example, about 16 W/(m K) is placed between a pair of metal layers made of a metal with a high thermal conductivity (for example, pure copper of about 370 W/(m·K)). K) of SUS304 and SUS630, about 26 W/(m K) of stainless steel such as SUS430, etc.) In the case of a composite metal plate having an intermediate layer, Kx is much larger than Kz, so the heat conduction characteristics are affected. Anisotropy occurs and the AIS becomes a very large value.

FIG. 1 is a diagram schematically showing the layer structure of one embodiment of the composite metal plate for heat diffusion according to the present invention. The composite metal plate 1 shown in FIG. 1 has T of 500 μm or less. This composite metal plate 1 is a clad plate material having a three-layer structure (copper layer/stainless steel layer/copper layer). Such a composite metal plate for heat diffusion has, for example, heat conduction properties applicable to applications whose main purpose is to dissipate the heat of the heat generating element to the outside of the heat generating element, and also has mechanical properties suitable for the use. should. From this point of view, the composite metal plate 1 preferably has T of 200 μm or less, more preferably 100 μm or less, as long as it satisfies the required properties such as thermal conductivity and mechanical properties for the application. is more preferably 50 μm or less. It should be noted that the lower limit of T of the composite metal plate 1 should be considered different depending on its application, and is not particularly limited. For example, T of the composite metal plate 1 may be 100 μm or more and 500 μm or less, 50 μm or more and 100 μm or less, or 10 μm or more and 50 μm or less.

This composite metal plate 1 can be used as a thermal diffusion member such as a heat radiating member or a heat transfer member mounted in small devices and devices such as mobile personal computers and mobile phones, or as a thermal diffusion component, as T becomes smaller. By using it, it is possible to contribute to further weight reduction and compactness of small equipment and devices. Although the composite metal plate for heat diffusion according to the present invention is suitable for heat diffusion, it can also be used for purposes other than heat diffusion, such as a conductive member, a chassis, a case, a frame, or the like. be.

In this composite metal plate 1, a first copper layer 2, a stainless steel layer 3 and a second copper layer 4 are joined in this order. That is, in this composite metal plate 1 , the copper layers (the first copper layer 2 and the second copper layer 4 ) are joined to the front and back surfaces of the stainless steel layer 3 . With this configuration, considering the material of the copper layer, the front and back surfaces of the stainless steel layer 3 with poor wettability are covered with the copper layer with good wettability. It can be easily attached. In consideration of the material of the copper layer, the copper layer having a high thermal conductivity covers the front and back surfaces of the stainless steel layer 3, which has a lower thermal conductivity than the copper layer. Compared to a plate or a composite metal plate (copper layer/stainless steel layer/copper layer) with an excessively small Tc, it can have favorable thermal conductivity properties in all of the X, Y and Z directions. , especially in the X and Y directions, it can have more favorable heat conduction properties. In addition, considering the material of the stainless steel layer 3, the stainless steel layer 3 having a large mechanical strength is used to form the central portion of the copper layer (the first copper layer 2 and the second copper layer), which has a lower mechanical strength than the stainless steel layer 3. 4) is reinforced. and Z-direction can have favorable mechanical properties.

In this composite metal plate 1, the ratio (thickness ratio) determined by Ts/(Tc1+Tc2), that is, Ts/Tc, is 0.2 or more and 5 or less. By configuring the composite metal plate 1 to have a smaller Ts/Tc, compared to a configuration having a larger Ts/Tc, the composite metal plate 1 can have preferable heat conduction characteristics in the Z direction, and the overall heat conduction characteristics are also preferable. can be leveled. Moreover, this composite metal plate 1 can have favorable mechanical properties by configuring Ts/Tc to be larger. From this point of view, the composite metal plate 1 in which Ts/Tc is 0.2 or more is a composite metal plate (copper layer/stainless steel layer/copper layer) can have favorable mechanical properties. On the other hand, the composite metal plate 1 having a Ts/Tc of 5 or less is a composite metal plate (copper layer/stainless steel layer/copper layer) having an excessively small Tc compared to a stainless steel plate made of a single stainless steel plate. can have favorable heat transfer properties compared to If Ts/Tc is less than 0.2, the mechanical properties of the composite metal plate become insufficient, and if Ts/Tc exceeds 5.0, the thermal conductivity properties of the composite metal plate become insufficient.

To give an example of Ts/(Tc1+Tc2), that is, Ts/Tc, of the composite metal plate 1, the thickness ratio (Tc1:Ts:Tc2) of each layer constituting the copper layer/stainless steel layer/copper layer is 1:3:1. Ts/Tc in the case is 3/(1+1)=1.5. When the ratio of copper layer:stainless steel layer:copper layer is 2:1:2, Ts/Tc is 1/(2+2)=0.25. When the ratio of copper layer:stainless steel layer:copper layer is 1:6:1, Ts/Tc is 6/(1+1)=3. When the ratio of copper layer:stainless steel layer:copper layer is 1:8:1, Ts/Tc is 8/(1+1)=4.

The composite metal plate 1 has a thermal conductivity ratio of 4.4 or more and 6.8 or less, which is determined by Kx/Kz in the X direction and the Z direction. As a result, the composite metal plate 1 can have heat conduction properties suitable for the desired application of heat diffusion and mechanical properties suitable for the intended use. Balance is preferred. In addition, the composite metal plate 1 with Kx/Kz, that is, AIS of 4.4 or more and 6.8 or less has directional characteristics of heat conduction characteristics, that is, anisotropy, but in general heat diffusion applications is an applicable level, and it is easy to select the anisotropy of the thermal conductivity properties suitable for the application.

As described above, the desired application of heat diffusion, for example, as a heat diffusion member such as a heat dissipation member or a heat transfer member mounted in a small device or device such as a mobile personal computer or a mobile phone, or as a heat diffusion part Composite metal plate 1 having the above-described configuration is preferable for appropriately and simply selecting a composite metal plate for heat diffusion that is suitable for use.

As one method of selecting the composite metal plate 1 using Ts/Tc, first, Ts/Tc is selected, and then, by referring to the graphs shown in FIGS. A simple method is to select the composite metal plate 1 that satisfies the properties, that is, the thermal conductivity characteristics (Kx, Kz) and the degree of anisotropy of the thermal conductivity characteristics (AIS). Alternatively, first, the required characteristics (Kx, Kz, AIS, etc.) are selected, and then the composite metal plate 1 that satisfies Ts/Tc according to the application is selected by referring to the graphs shown in FIGS. 11 to 13 described later. The selection method is simple. By the selection method of the composite metal plate 1 using such Ts/Tc, it is possible to appropriately and easily find the configuration of the composite metal plate 1 according to various uses of heat diffusion.

The composite metal plate 1 may have Kx of 340 W/(m·K) or less and Kz of 20 W/(m·K) or more. A composite metal plate having Kx exceeding 340 W/(m·K) is considered to be , Ts/Tc of less than 0.2, the effectiveness of the stainless steel layer is substantially lost and may not have suitable mechanical properties for the desired application of heat diffusion. Similarly, a composite metal plate having a Kz of less than 20 W/(m·K) has a Ts/Tc of more than 5.0 and substantially loses the effectiveness of the first copper layer and the second copper layer, It may not have suitable heat transfer properties for the desired application of heat spreading.

The first copper layer 2 and the second copper layer 4 forming the composite metal plate 1 are made of pure copper containing Cu (element) in an amount of 99% by mass or more, or have a higher thermal conductivity than the stainless steel forming the stainless steel layer 3. It is preferably made of a copper alloy with a high modulus. In this case, elements other than Cu contained in pure copper are unavoidable impurities. Specifically, when pure copper is used for the copper layer, a material having high thermal conductivity, such as oxygen-free copper, phosphorus-deoxidized copper, and tough-pitch copper, which belongs to the category of C1000 series (JIS standard), is preferable. When a copper alloy is used for the copper layer, it preferably belongs to the C2000 series (JIS standard), which has relatively high thermal conductivity. In addition, as other copper alloys, in order to suppress the coarsening of the crystals of the copper layer, those containing 0.05% by mass or more and 0.15% by mass or less of Zr (zirconium) of C1510 (JIS standard), mass A material containing Ti (titanium) at a ratio of 4 ppm to 55 ppm, S (sulfur) at 2 ppm to 12 ppm, and O (oxygen) at 2 ppm to 30 ppm can also be used. Since the copper alloy containing Zr has a suitable thermal conductivity and mechanical strength, it can be expected to reduce the thickness of the copper layer that constitutes the composite metal plate. The copper alloy containing a small amount of Ti and the like has a corresponding thermal conductivity property, and TiO, TiO ₂ , TiS, Ti—O—S, etc. exist in the form of compounds or aggregates, and Ti, S, etc., form a solid solution. Therefore, the mechanical properties of the copper layer can be expected to be improved.

Here, although the first copper layer 2 and the second copper layer 4 do not have to be made of the same material, they are preferably made of the same material. The same material means that the composition of the first copper layer 2 and the composition of the second copper layer 4 are substantially the same material (for example, the type symbol in the JIS standard is the same), and the property of the first copper layer 2 and the properties of the second copper layer 4 are substantially the same (for example, the elongation during rolling is the same value or within a predetermined range (variation)), and both cases. For example, when the composite metal plate 1 is produced by clad rolling, it is preferable that the first copper layer 2 and the second copper layer 4 have the same composition in consideration of rolling stability.

The stainless steel layer 3 constituting the composite metal plate 1 is composed of Cr (chromium) of 10.5% or more and 30% or less, Ni (nickel) of 0.6% or more and 25% or less, and 0.20% by mass. It is preferably made of stainless steel composed of C (carbon) and the balance Fe (iron) and unavoidable impurities. When the above stainless steel is used for the stainless steel layer 3, the stainless steel constituting the stainless steel layer 3 is austenitic stainless steel or precipitation hardening by containing 0.6% or more and 25% or less of Ni and 0.20% or less of C. It can have properties (materials) characteristic of stainless steels. The stainless steel that constitutes the stainless steel layer 3 may be a general stainless steel that conforms to the ISO standard or JIS standard, and may be austenitic, ferritic, martensitic, or precipitation hardened stainless steel. Not limited. The ISO standard (ISO-15510) defines stainless steel as steel containing 1.2% by mass or less of C and 10.5% by mass or more of Cr. The JIS standard (JIS-G0203) defines stainless steel as an alloy steel containing the same amount of C and Cr as the ISO standard and having improved corrosion resistance.

The stainless steel constituting the stainless steel layer 3 has a composition containing, by mass %, 10.5% or more and 30% or less of Cr, 0.6% or more and 25% or less of Ni, and 0.20% or less of C. For example, it can be selected from stainless steels having a composition containing 15% or more and 27% or less of Cr, 5% or more and 23% or less of Ni, and 0.20% or less of C. A SUS layer composed of such stainless steel can have various characteristics characteristic of any of austenitic stainless steels such as SUS301, SUS304, SUS305, SUS310S, SUS316 and SUS316L (these are JIS standards). For example, when the composite metal plate 1 is applied to a heat diffusion component of a device or apparatus having an electronic component such as a semiconductor element, it may not be preferable for the heat diffusion component to be magnetized. In such a case, the stainless steel constituting the stainless steel layer 3 is preferably austenitic stainless steel, more preferably SUS300 series (JIS standard) austenitic stainless steel, and still more preferably C It is SUS316L (JIS standard), which has a low content and is less likely to be magnetized. In addition, SUS316L is, in mass%, 16% or more and 18% or less of Cr, 12% or more and 15% or less of Ni, 2% or more and 3% or less of Mo, 0.03% or less of C, and the balance It is an austenitic stainless steel composed of Fe and inevitable impurities.

In addition, the stainless steel constituting the stainless steel layer 3 contains 10.5% or more and 30% or less of Cr, 0.6% or more and 25% or less of Ni, and 0.20% or less of C by mass %. Among the stainless steels having a composition, for example, a stainless steel having a composition containing 14% or more and 19% or less of Cr, 2% or more and 8.5% or less of Ni, and 0.10% or less of C is selected. be able to. The stainless layer 3 made of such stainless steel contains 2% or more and 5% or less (preferably 3% or more and 5% or less) of Cu and 0.1% or more and 0.5% or less (preferably 0.15% or more and 0.15% or more) of Cu. .45% or less) of Nb (niobium), it is possible to have characteristics (material) characteristic of SUS630 (JIS standard) of precipitation hardening stainless steel, or 0.5% or more and 2% or less By further containing Al (preferably 0.75% or more and 1.5% or less), it is possible to have characteristics (material properties) characteristic of precipitation hardened stainless steel SUS631 (JIS standard).

Such a composite metal plate 1 (first copper layer 2/stainless steel layer 3/second copper layer 4) includes, for example, a first copper plate made of pure copper or a copper alloy, a stainless steel plate made of stainless steel, and a pure copper Alternatively, an engineer involved in clad rolling, including a clad rolling step of rolling the second copper plate composed of a copper alloy in this order to join the layers, and a step of performing diffusion annealing after clad rolling. can be produced by a clad plate manufacturing method well known to In the method for manufacturing the clad plate material (composite metal plate 1) described above, the clad rolling step may include a softening step (softening annealing) of the material to be rolled (plate material). It may include a step of performing rolling (finish rolling) to form a composite metal sheet 1 having a large thickness (thickness).

Next, an embodiment of a heat diffusion component according to the present invention using the composite metal plate 1 (composite metal plate for heat diffusion) described above will be described with specific configuration examples and with appropriate reference to the drawings. do.

(First configuration example)
FIG. 2 shows a layer configuration of a flat plate-shaped heat diffusion component 10, which is an embodiment of the heat diffusion component according to the present invention, shown as a first configuration example. Note that the shape, size, ratio, magnification, etc. of each member shown in FIG. 2 are exaggerated and modeled for clarity.

A flat plate-like heat diffusion component 10 shown in FIG. 2 as a first configuration example is composed of a first member 11 . The first member 11 has a T of 500 µm or less, a Ts/Tc of 0.2 or more and 5 or less, and a Kx/Kz of 4.4 or more and 6.8 or less. /stainless steel layer 3/second copper layer 4).

The flat plate-like heat diffusion component 10 directly or indirectly joins the heat sources 5a and 5b to the upper surface of the first member 11, that is, the flat portions 2a and 2b on the exposed surface of the first copper layer 2. It has possible heat source junction areas 2A, 2B. The heat sources 5a and 5b may be one, or three or more, and may be electronic components such as semiconductor elements, for example.

When the plate-shaped heat diffusion component 10 is used, the heat generated by the heat sources 5a and 5b is conducted to the first member 11 in contact with the heat sources 5a and 5b, and spreads from the flat portions 2a and 2b to the first copper layer 2. Conduct inside. The heat conducted to the first copper layer 2 is conducted in the X, Y and Z directions inside the first copper layer 2 . The heat conducted in the X direction and the Y direction inside the first copper layer 2 is released to the outside through a heat radiation terminal (not shown) provided at the end of the first member 11 or the like, or It is released into the air (eg, into the atmosphere) from the exposed surface of layer 2 and diffuses. At the same time, the heat conducted in the Z direction inside the first copper layer 2 is conducted inside the stainless steel layer 3 . The heat conducted to the stainless steel layer 3 is directed toward the second copper layer 4 adjacent to the direction in which the level of thermal energy is low and heat is easily conducted, that is, the Z direction in which the conduction distance is relatively small. Conduct preferentially. The heat conducted to the second copper layer 4 is conducted inside the second copper layer 4 in the X, Y and Z directions. The heat conducted in the X direction and the Y direction inside the second copper layer 4 is released to the outside via a heat radiation terminal (not shown) provided at the end of the first member 11 or the like, or It is released into the air (eg, the atmosphere) from the exposed surface of layer 4 and diffuses.

The flat plate-like heat diffusion component 10 has appropriate heat conduction characteristics due to the copper layers (the first copper layer 2 and the second copper layer 4) and appropriate mechanical characteristics due to the stainless steel layer 3, which constitute the first member 11. have. As a result, such a plate-like heat diffusion component 10 can be mounted as a heat diffusion component such as a heat radiating member or a heat transfer member mounted on small devices and devices such as mobile personal computers and mobile phones. , can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to making the devices and devices thinner, more compact, and lighter.

(Second configuration example)
FIG. 3 is a cross-sectional configuration of a housing-like heat diffusion component 20, which is an embodiment of the heat diffusion component according to the present invention, shown as a second configuration example. Note that the shape, size, ratio, magnification, etc. of each member shown in FIG. 3 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

A housing-shaped heat diffusion component 20 shown in FIG. 3 as a second configuration example includes a first member 21 , a second member 22 , and an internal space 24 . That is, it has an internal space composed of the first member and the second member. Both the first member 21 and the second member 22 have a T of 500 µm or less, a Ts/Tc of 0.2 or more and 5 or less, and a Kx/Kz of 4.4 or more and 6.8 or less. 1 (first copper layer 2/stainless steel layer 3/second copper layer 4). The first member 21 has a bent portion 21a at one end (right side in the X direction) and a bent portion 21b at the other end (left side in the X direction). The second member 22 has a bent portion 22a at one end (right side in the X direction) and a bent portion 22b at the other end (left side in the X direction). The first member 21 and the second member 22 are such that the end surfaces 21c and 22c of the bent portions 21a and 22a are butted against each other so that the internal space 24 is airtightly sealed (preferably vacuum sealed). The end face portions 21d and 22d of the bent portions 21b and 22b are butted and joined.

Here, the first member 21 and the second member 22 may be joined by a method using a joining material such as solder or silver solder. A method using thermal diffusion (pressure diffusion bonding) is preferable from the viewpoint of improving reliability of sealing. Pressure diffusion bonding utilizes heat diffusion generated by heating (heating) the surfaces to be bonded under a load so that the surfaces to be bonded are pressed against each other, and bonds the surfaces to be bonded (the end surface portion 21c and the end surface portion 22c) to each other. , and a method of joining the end face portion 21d and the end face portion 22d). The heating (heat treatment) in this case is preferably performed in a non-oxidizing atmosphere using, for example, nitrogen gas, argon gas, or a mixed gas of nitrogen and argon. Furthermore, it is required to maintain the temperature at 600° C. or higher and 1000° C. or lower.

The internal space 24 of the housing-like heat diffusion component 20 is hermetically sealed (preferably vacuum sealed) by the first member 21 and the second member 22 . The members involved in hermetic sealing of the internal space 24 are not limited to the first member 21 and the second member 22, and other members such as heat dissipation terminals (not shown) may be involved. The internal space 24 that is hermetically sealed (preferably decompressed) is used as a heat flow path by sealing a working fluid (refrigerant) therein that enables heat transport by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, CFC substitute, alcohol, or organic compounds such as acetone can be used, but from the viewpoint of safety, low cost, ease of handling, etc., it is preferable to use pure water. .

The housing-shaped heat diffusion component 20 has the heat sources 5a and 5b directly or indirectly attached to the upper surface of the first member 21, that is, the flat portions 2a and 2b on the exposed surface of the first copper layer 2. Bondable heat source bond regions 2A, 2B may be provided. Note that the sites where the heat source bonding regions 2A and 2B are provided may be set as necessary, and are not limited to the surface of the first member 21 . Also, the number of heat sources 5a and 5b may be one, or three or more, and may be, for example, electronic components such as semiconductor elements.

When the housing-shaped heat diffusion component 20 is used, the heat generated by the heat sources 5a and 5b is conducted to the first member 21 in contact with the heat sources 5a and 5b, and the first copper layer 2 is transferred from the flat portions 2a and 2b. conducts to the inside of the The heat conducted to the first copper layer 2 is conducted inside the first copper layer 2 in the X, Y and Z directions. The heat conducted in the X direction and the Y direction inside the first copper layer 2 is conducted from the joints 23a and 23b to the second member 22, and is connected to the end portion of the first member 21 by a heat dissipation terminal (not shown) or the like. is provided, it is released to the outside through it and diffuses, and part of it is released into the air (for example, the atmosphere) from the exposed surface of the first copper layer 2 and diffuses. At the same time, the heat conducted in the Z direction inside the first copper layer 2 is conducted inside the stainless steel layer 3 . The heat conducted to the stainless steel layer 3 is directed toward the second copper layer 4 adjacent to the direction in which the level of thermal energy is low and heat is easily conducted, that is, the Z direction in which the conduction distance is relatively small. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed toward the inner space 24 in which the working fluid (refrigerant), which has a low energy level and is easy to conduct heat, exists inside the second copper layer 4, that is, toward the Z direction. conducts to The heat conducted from the surface of the second copper layer 4 constituting the first member 21 to the working fluid (refrigerant) in the internal space 24 is transported by the working fluid (refrigerant), and the heat dissipation provided at the end of the internal space 24, etc. It is discharged to the outside through a terminal (not shown) or the like. The heat conducted from the first member 21 to the second member 22 is dissipated and diffused to the outside through a path similar to the behavior of the first member 21 .

The housing-like heat diffusion component 20 has appropriate heat conduction characteristics due to the copper layers (first copper layer 2, second copper layer 4) and the stainless steel layer 3, which constitute the first member 21 and the second member 22. It has moderate mechanical properties. As a result, the housing-like heat diffusion component 20 can be made thinner by reducing the thickness of the housing (the length in the Z direction). Such a housing-shaped heat diffusion component 20 can be said to be a flat plate-shaped heat pipe with a high heat radiation effect (thermal diffusion effect), and is suitable for use as the housing of the above-described vapor chamber. In addition, the housing-shaped heat diffusion component 20 can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member to be mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to making the devices and devices thinner, more compact, and lighter.

(Modification of Second Configuration Example)
FIG. 4 is a cross-sectional configuration of a housing-like heat diffusion component 20A, which is an embodiment of the heat diffusion component according to the present invention, shown as a modification of the second configuration example. The shape, size, ratio, magnification, etc. of each member shown in FIG. 4 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

As a modification of the second configuration example, a housing-shaped heat diffusion component 20A shown in FIG. and a support portion 25 . The support portion 25 is arranged in the internal space and joined to the second copper layer 4 forming the first member 21 and the second copper layer 4 forming the second member 22 . As a result, the mechanical strength of the housing-shaped heat diffusion component 20A is increased, so that the housing-shaped heat diffusion component 20A can be made thinner. Further, the internal space is partitioned into two internal spaces 24a and 24b by the support portion 25, and the two internal spaces 24a and 24b can be connected by providing the communication path 25a in the support portion 25. FIG. In this case, the number of connecting paths 25a provided in the support portion 25 is not limited to one, and a plurality of connecting paths can be provided as necessary. In addition, the first member 21 and the second member 22 constituting the heat diffusion component 20A, the method of joining the first member 21 and the second member 22, the heat sources 5a and 5b and the heat source joining regions 2A and 2B, and The description of the working fluid (refrigerant) hermetically sealed (preferably decompression sealed) in the internal spaces 24a and 24b will be omitted here, and the description of the heat diffusion component 20 described above will be referred to.

When the case-shaped heat diffusion component 20A is used, heat generated by the heat sources 5a and 5b is transferred to the first member 21 in contact with the heat sources 5a and 5b, as in the case of the case-shaped heat diffusion component 20 described above. from the planar portions 2a, 2b of the first copper layer 2, the stainless steel layer 3 and the second copper layer 4, most of which is from the exposed surface of the second copper layer 4 to the level of the thermal energy in the internal spaces 24a, 25b It conducts to a working fluid (refrigerant) with a low energy, is transported by the working fluid (refrigerant), and is discharged to the outside through heat radiation terminals (not shown) provided at the ends of the internal spaces 24a and 24b. At this time, even if the amount of heat conducted to the working fluid (refrigerant) in the internal space 24a differs from the amount of heat conducted to the working fluid (refrigerant) in the internal space 24b, the working fluid in the internal spaces 24a and 25n The working fluid (refrigerant) can move through the communication channel 25a of the support 25 so that the level of thermal energy of the (refrigerant) is balanced. The heat conducted from the first member 21 to the second member 22 is dissipated and diffused to the outside through a path similar to the behavior of the first member 21 .

The housing-shaped heat diffusion component 20A has moderate heat conduction characteristics due to the copper layers (the first copper layer 2 and the second copper layer 4) and the stainless steel layer 3, which constitute the first member 21 and the second member 22. It has moderate mechanical properties. Furthermore, the housing-shaped heat diffusion component 20A has a support portion 25 joined to the first member 21 and the second member 22 . As a result, the housing-like heat diffusion component 20A is reinforced, and the thickness of the housing (the length in the Z direction) can be further reduced, so that the thickness can be further reduced. Such a case-shaped heat diffusion component 20A is suitable for use as the case of the above-described vapor chamber. Further, the housing-shaped heat diffusion component 20A can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member to be mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to further thinning, compactness, and weight reduction of the devices and devices described above.

(Third configuration example)
FIG. 5 is a cross-sectional configuration of a housing-like heat diffusion component 30, which is an embodiment of the heat diffusion component according to the present invention, shown as a third configuration example. Note that the shape, size, ratio, magnification, etc. of each member shown in FIG. 5 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

A housing-shaped heat diffusion component 30 shown in FIG. 5 as a third configuration example includes a first member 31 , a second member 32 , and an internal space 34 . That is, it has an internal space composed of the first member and the second member. Both the first member 31 and the second member 32 have a T of 500 μm or less, a Ts/Tc of 0.2 or more and 5 or less, and a Kx/Kz of 4.4 or more and 6.8 or less. 1 (first copper layer 2/stainless steel layer 3/second copper layer 4). The first member 31 has a bent portion 31a at one end (right side in the X direction) and a bent portion 31b at the other end (left side in the X direction). The second member 32 is formed in a flat plate shape. The first member 31 and the second member 32 are arranged such that the end surface portion 31c of the bent portion 31a of the first member 31 is the flat surface of the second member 32 so that the internal space 34 is airtightly sealed (preferably vacuum sealed). The end surface portion 31d of the bent portion 31b of the first member 31 is abutted against the flat portion 32b of the second member 32 and joined to the portion 32a.

Here, the first member 31 and the second member 32 may be joined by a method using a joining material such as solder or silver solder. A method using thermal diffusion (pressure diffusion bonding) is preferable from the viewpoint of improving reliability of sealing. In pressure diffusion bonding, the surfaces to be bonded (the end surface portion 31c and the flat portion 32a) are bonded together by utilizing thermal diffusion generated by heating (heating) the surfaces to be bonded under a load so that they are pressed against each other. , and a method of joining the end surface portion 31d and the plane portion 32b). The heating (heat treatment) in this case is preferably performed in a non-oxidizing atmosphere using, for example, nitrogen gas, argon gas, or a mixed gas of nitrogen and argon. Furthermore, it is required to maintain the temperature at 600° C. or higher and 1000° C. or lower.

An internal space 34 of the housing-like heat diffusion component 30 is hermetically sealed (preferably vacuum sealed) by the first member 31 and the second member 32 . It should be noted that the members involved in hermetic sealing of the internal space 34 are not limited to the first member 31 and the second member 32, and other members such as heat dissipation terminals (not shown) may be involved. The internal space 34 that is hermetically sealed (preferably decompressed) is used as a heat flow path by sealing a working fluid (refrigerant) therein that enables heat transport by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, CFC alternative, alcohol, or organic compounds such as acetone can be used. From the viewpoint of safety, low cost, ease of handling, etc., it is preferable to use pure water. .

The housing-like heat diffusion component 30 has the heat sources 5a and 5b directly or indirectly attached to the upper surface of the first member 31, that is, the flat portions 2a and 2b on the exposed surface of the first copper layer 2. Bondable heat source bond regions 2A, 2B may be provided. Note that the sites where the heat source bonding regions 2A and 2B are provided may be set according to need, and are not limited to the surface of the first member 31 . Also, the number of heat sources 5a and 5b may be one, or three or more, and may be, for example, electronic components such as semiconductor elements.

When the housing-shaped heat diffusion component 30 is used, the heat generated by the heat sources 5a and 5b is conducted to the first member 31 in contact with the heat sources 5a and 5b, and spreads from the flat portions 2a and 2b to the first copper layer 2. conducts to the inside of the The heat conducted to the first copper layer 2 is conducted inside the first copper layer 2 in the X, Y and Z directions. The heat conducted in the X direction and the Y direction inside the first copper layer 2 is conducted from the joints 33a and 33b to the second member 32, and is connected to the end portion of the first member 31 by a heat dissipation terminal (not shown) or the like. is provided, it is released to the outside through it and diffuses, and part of it is released into the air (for example, the atmosphere) from the exposed surface of the first copper layer 2 and diffuses. At the same time, the heat conducted in the Z direction inside the first copper layer 2 is conducted inside the stainless steel layer 3 . The heat conducted to the stainless steel layer 3 is directed toward the second copper layer 4 adjacent to the direction in which the level of thermal energy is low and heat is easily conducted, that is, the Z direction in which the conduction distance is relatively small. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed toward the inner space 34 where the working fluid (refrigerant), which has a low energy level and is easy to conduct heat, exists inside the second copper layer 4, that is, toward the Z direction. conducts to The heat conducted from the surface of the second copper layer 4 constituting the first member 31 to the working fluid (refrigerant) in the internal space 34 is transported by the working fluid (refrigerant), and the heat dissipation provided at the end of the internal space 34, etc. It is discharged to the outside through a terminal (not shown) or the like. The heat conducted from the first member 31 to the second member 32 is dissipated and diffused to the outside through a path similar to the behavior of the first member 31 .

The housing-shaped heat diffusion component 30 has appropriate heat conduction characteristics due to the copper layers (first copper layer 2, second copper layer 4) and the stainless steel layer 3, which constitute the first member 31 and the second member 32. It has moderate mechanical properties. As a result, the housing-shaped heat diffusion component 30 can be made thinner by reducing the thickness of the housing (the length in the Z direction). Such a housing-shaped heat diffusion component 30 can be said to be a flat plate-shaped heat pipe with a high heat radiation effect (thermal diffusion effect), and is suitable for use as the housing of the above-described vapor chamber. In addition, the housing-shaped heat diffusion component 30 can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member to be mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to making the devices and devices thinner, more compact, and lighter.

(Modification of the third configuration example)
FIG. 6 is a cross-sectional configuration of a housing-like heat diffusion component 30A, which is an embodiment of the heat diffusion component according to the present invention, shown as a modification of the third configuration example. The shape, size, ratio, magnification, etc. of each member shown in FIG. 6 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

As a modification of the third configuration example, a housing-shaped heat diffusion component 30A shown in FIG. and further includes a support portion 35 . The support portion 35 is arranged in the internal space and joined to the second copper layer 4 forming the first member 31 and the second copper layer 4 forming the second member 32 . As a result, the mechanical strength of the housing-shaped heat diffusion component 30A is increased, so that the housing-shaped heat diffusion component 30A can be made thinner. Moreover, although the internal space is divided into two internal spaces 34a and 34b by the support portion 35, the two internal spaces 34a and 34b can be connected by providing the communication path 35a in the support portion 35. FIG. In this case, the number of connecting passages 35a provided in the support portion 35 is not limited to one, and a plurality of connecting passages 35a may be provided as necessary. In addition, the first member 31 and the second member 32 constituting the heat diffusion component 30A, the method of joining the first member 31 and the second member 32, the heat sources 5a and 5b and the heat source joining regions 2A and 2B, and The description of the working fluid (refrigerant) hermetically sealed (preferably decompression sealed) in the two internal spaces 34a and 34b is omitted here, and the description of the heat diffusion component 30 described above is referred to.

When the housing-shaped heat diffusion component 30A is used, as with the housing-shaped heat diffusion component 30 described above, the heat generated by the heat sources 5a and 5b is transferred to the first member 31 in contact with the heat sources 5a and 5b. from the flat portions 2a, 2b of the first copper layer 2, the stainless steel layer 3 and the second copper layer 4, most of which is from the exposed surface of the second copper layer 4 to the level of the thermal energy in the internal spaces 34a, 35b It conducts to a working fluid (refrigerant) with a low energy, is transported by the working fluid (refrigerant), and is discharged to the outside through heat radiation terminals (not shown) provided at the ends of the internal spaces 34a and 34b. At this time, even if the amount of heat conducted to the working fluid (refrigerant) in the internal space 34a differs from the amount of heat conducted to the working fluid (refrigerant) in the internal space 34b, the working fluid in the internal spaces 34a and 35n The working fluid (refrigerant) can move through the communication path 35a of the support 35 so that the thermal energy levels of the (refrigerant) are balanced. The heat conducted from the first member 31 to the second member 32 is dissipated and diffused to the outside through a path similar to the behavior of the first member 31 .

The housing-shaped heat diffusion component 30A has appropriate heat conduction characteristics due to the copper layers (the first copper layer 2 and the second copper layer 4) and the stainless steel layer 3, which constitute the first member 31 and the second member 32. It has moderate mechanical properties. Further, the housing-shaped heat diffusion component 30A has a support portion 35 joined to the first member 31 and the second member 32 . As a result, the housing-shaped heat diffusion component 30A is reinforced, and the thickness of the housing (the length in the Z direction) can be further reduced, so that the thickness can be further reduced. Such a housing-like heat diffusion component 30A is suitable for use as the housing of the above-described vapor chamber. Further, the case-shaped heat diffusion component 30A can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to further thinning, compactness, and weight reduction of the devices and devices described above.

(Fourth configuration example)
FIG. 7 is a cross-sectional configuration of a housing-like heat diffusion component 40, which is an embodiment of the heat diffusion component according to the present invention, shown as a fourth configuration example. The shape, size, ratio, magnification, etc. of each member shown in FIG. 7 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

A housing-shaped heat diffusion component 40 shown in FIG. 7 as a fourth configuration example includes a first member 41 , a second member 42 , and an internal space 44 . That is, it has an internal space composed of the first member and the second member. The first member 41 has a T of 500 µm or less, a Ts/Tc of 0.2 or more and 5 or less, and a Kx/Kz of 4.4 or more and 6.8 or less. /stainless steel layer 3/second copper layer 4). The first member 41 has a bent portion 41a at one end (right side in the X direction) and a bent portion 41b at the other end (left side in the X direction). The second member 42 is formed by combining a copper plate portion 42a made of copper or a copper alloy and a porous copper portion 42b made of copper or a copper alloy. Note that the copper plate portion 42a that constitutes the second member 42 can also be configured using a stainless plate made of stainless steel. By arranging such a porous copper portion 42b facing the internal space 44, the surface area of the second member 42 in contact with the internal space 44 is increased, and the working fluid (refrigerant) present in the internal space 44 from the second member 42 side heat can be easily conducted to the working fluid (refrigerant), and the efficiency of heat transport by the working fluid (refrigerant) can be improved.

The form of the copper plate portion 42a and the porous copper portion 42b that constitute the second member 42 is a form in which the porous copper portion 42b having a three-dimensionally porous form made of a sintered member or the like is joined to the copper plate portion 42a. Alternatively, one surface of the copper plate is subjected to etching treatment or anodizing treatment to form a porous copper portion 42b having a planar porous shape in which irregularities are dispersedly arranged, and the copper plate is A configuration in which the remainder is the copper plate portion 42a may be used.

The first member 41 and the second member 42 are arranged such that the end face portion 42c of the second member 42 is aligned with the flat surface of the bent portion 41a of the first member 41 so that the internal space 44 is airtightly sealed (preferably vacuum sealed). The end surface portion 42d of the second member 42 is abutted against the flat portion 41d of the bent portion 41b of the first member 41 and joined to the portion 41c. The first member 41 and the second member 42 may be joined by a method using a joining material such as solder or silver solder. A method using thermal diffusion (pressure diffusion bonding) is preferable from the viewpoint of improving the reliability of the bonding. In pressurized diffusion bonding, the surfaces to be bonded (the flat portion 41c and the end surface portion 42c) are bonded together by utilizing thermal diffusion generated by heating (heating) the surfaces to be bonded under a load so that they press each other. , and a method of joining the plane portion 41d and the end surface portion 42d). The heating (heat treatment) in this case is preferably performed in a non-oxidizing atmosphere using, for example, nitrogen gas, argon gas, or a mixed gas of nitrogen and argon. Furthermore, it is required to maintain the temperature at 600° C. or higher and 1000° C. or lower.

An internal space 44 of the housing-like heat diffusion component 40 is hermetically sealed (preferably vacuum sealed) by the first member 41 and the second member 42 . Note that the members involved in hermetic sealing of the internal space 44 are not limited to the first member 41 and the second member 42, and other members such as heat dissipation terminals (not shown) may be involved. The internal space 44 that is hermetically sealed (preferably decompressed) is used as a heat flow path by sealing a working fluid (refrigerant) therein that enables heat transport by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, CFC substitute, alcohol, or organic compounds such as acetone can be used, but from the viewpoint of safety, low cost, ease of handling, etc., it is preferable to use pure water. .

The housing-shaped heat diffusion component 40 has the heat sources 5a and 5b directly or indirectly attached to the upper surface of the first member 41, that is, the flat portions 2a and 2b on the exposed surface of the first copper layer 2. Bondable heat source bond regions 2A, 2B may be provided. Note that the sites where the heat source bonding regions 2A and 2B are provided may be set as necessary, and are not limited to the surface of the first member 41 . Also, the number of heat sources 5a and 5b may be one, or three or more, and may be, for example, electronic components such as semiconductor elements.

When the housing-shaped heat diffusion component 40 is used, the heat generated by the heat sources 5a and 5b is conducted to the first member 41 in contact with the heat sources 5a and 5b, and spreads from the flat portions 2a and 2b to the first copper layer 2. conducts to the inside of the The heat conducted to the first copper layer 2 is conducted inside the first copper layer 2 in the X, Y and Z directions. The heat conducted in the X direction and the Y direction inside the first copper layer 2 is conducted from the joints 43a and 43b to the second member 42, and is connected to the end portion of the first member 41 by a heat dissipation terminal (not shown) or the like. is provided, it is released to the outside through it and diffuses, and part of it is released into the air (for example, the atmosphere) from the exposed surface of the first copper layer 2 and diffuses. At the same time, the heat conducted in the Z direction inside the first copper layer 2 is conducted inside the stainless steel layer 3 . The heat conducted to the stainless steel layer 3 is directed toward the second copper layer 4 adjacent to the direction in which the level of thermal energy is low and heat is easily conducted, that is, the Z direction in which the conduction distance is relatively small. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed toward the inner space 44 where the working fluid (refrigerant), which has a low energy level and is easy to conduct heat, exists inside the second copper layer 4, that is, toward the Z direction. conducts to The heat conducted from the surface of the second copper layer 4 constituting the first member 41 to the working fluid (refrigerant) in the internal space 44 is transported by the working fluid (refrigerant), and the heat dissipation provided at the end of the internal space 44, etc. It is discharged to the outside through a terminal (not shown) or the like. The heat conducted from the first member 41 to the second member 42 is conducted to the working fluid (refrigerant) in the internal space 44 via the porous copper portion 42b and is radiated to the outside and diffused. It is released into the air (eg, into the atmosphere) from the exposed surface of portion 42a and diffuses.

The housing-like heat diffusion component 40 has appropriate heat conduction properties due to the copper layers (the first copper layer 2 and the second copper layer 4) and the appropriate mechanical properties due to the stainless steel layer 3, which constitute the first member 41. have As a result, the housing-shaped heat diffusion component 40 can be made thinner by reducing the thickness of the housing (the length in the Z direction). Such a housing-shaped heat diffusion component 40 can be said to be a flat plate-shaped heat pipe with a high heat radiation effect (thermal diffusion effect), and is suitable for use as the housing of the above-described vapor chamber. In addition, the housing-shaped heat diffusion component 40 can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member to be mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to making the devices and devices thinner, more compact, and lighter.

(Modification of the fourth configuration example)
FIG. 8 is a cross-sectional configuration of a housing-like heat diffusion component 40A, which is an embodiment of the heat diffusion component according to the present invention, shown as a modification of the fourth configuration example. The shape, size, ratio, magnification, etc. of each member shown in FIG. 8 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

As a modification of the fourth configuration example, a housing-shaped heat diffusion component 40A shown in FIG. and further includes a support portion 45 . The support portion 45 is arranged in the internal space and joined to the second copper layer 4 forming the first member 41 and the copper plate portion 42 a forming the second member 42 . As a result, the mechanical strength of the housing-shaped heat diffusion component 40A is increased, so that the housing-shaped heat diffusion component 40A can be made thinner. Further, the internal space is partitioned into two internal spaces 44a and 44b by the support portion 45, and the two internal spaces 44a and 44b can be connected by providing the communication path 45a in the support portion 45. FIG. In this case, the number of connecting passages 45a provided in the support portion 45 is not limited to one, and a plurality of connecting passages 45a may be provided as necessary. In addition, the first member 41 and the second member 42 constituting the heat diffusion component 40A, the method of joining the first member 41 and the second member 42, the heat sources 5a and 5b and the heat source joining regions 2A and 2B, and The description of the working fluid (refrigerant) hermetically sealed (preferably vacuum sealed) in the two internal spaces 44a and 44b will be omitted here, and the description of the heat diffusion component 40 described above will be referred to.

When the case-shaped heat diffusion component 40A is used, heat generated by the heat sources 5a and 5b is transferred to the first member 41 in contact with the heat sources 5a and 5b, as in the case of the case-shaped heat diffusion component 40 described above. From the planar portions 2a, 2b of the first copper layer 2, the stainless steel layer 3, and the second copper layer 4, most of which is from the exposed surface of the second copper layer 4 to the level of the thermal energy in the internal spaces 44a, 45b It conducts to a working fluid (refrigerant) with a low energy, is transported by the working fluid (refrigerant), and is discharged to the outside through heat radiation terminals (not shown) provided at the ends of the internal spaces 34a and 34b. At this time, even if the amount of heat conducted to the working fluid (refrigerant) in the internal space 44a differs from the amount of heat conducted to the working fluid (refrigerant) in the internal space 44b, the working fluid in the internal spaces 44a and 45n The working fluid (refrigerant) can move through the communication path 45a of the support 45 so that the level of thermal energy of the (refrigerant) is balanced. The heat conducted from the first member 41 to the second member 42 is conducted to the working fluid (refrigerant) in the internal space 44 via the porous copper portion 42b and is radiated to the outside and diffused. It is released into the air (eg, into the atmosphere) from the exposed surface of portion 42a and diffuses.

The housing-shaped heat diffusion component 40A has appropriate heat conduction characteristics due to the copper layers (the first copper layer 2 and the second copper layer 4) and appropriate mechanical characteristics due to the stainless steel layer 3, which constitute the first member 41. have Furthermore, the housing-shaped heat diffusion component 40A has a support portion 45 joined to the first member 41 and the second member 42 . As a result, the housing-shaped heat diffusion component 40A is reinforced, and the thickness of the housing (the length in the Z direction) can be further reduced, so that the thickness can be further reduced. Such a housing-like heat diffusion component 40A is suitable for use as the housing of the above-described vapor chamber. In addition, the housing-shaped heat diffusion component 40A can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to further thinning, compactness, and weight reduction of the devices and devices described above.

(Fifth configuration example)
FIG. 9 is a cross-sectional configuration of a housing-like heat diffusion component 50, which is an embodiment of the heat diffusion component according to the present invention, shown as a fifth configuration example. The shape, size, ratio, magnification, etc. of each member shown in FIG. 9 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

A housing-shaped heat diffusion component 50 shown in FIG. 8 as a fifth configuration example includes a first member 51 , a second member 52 , and an internal space 54 . That is, it has an internal space composed of the first member and the second member. The first member 51 has a T of 500 µm or less, a Ts/Tc of 0.2 or more and 5 or less, and a Kx/Kz of 4.4 or more and 6.8 or less. /stainless steel layer 3/second copper layer 4). The first member 51 has a bent portion 51a at one end (right side in the X direction) and a bent portion 51b at the other end (left side in the X direction). The second member 52 is formed by combining a copper plate portion 52a made of copper or a copper alloy and a porous copper portion 52b made of copper or a copper alloy. The copper plate portion 52a forming the second member 52 can also be formed using a stainless steel plate. By arranging such a porous copper portion 52b facing the internal space 54, the surface area of the second member 52 in contact with the internal space 54 is increased, and the working fluid (refrigerant) present in the internal space 54 from the second member 52 side heat can be easily conducted to the working fluid (refrigerant), and the efficiency of heat transport by the working fluid (refrigerant) can be improved.

The form of the copper plate portion 52a and the porous copper portion 52b that constitute the second member 52 is a form in which the porous copper portion 52b having a three-dimensionally porous form made of a sintered member or the like is joined to the copper plate portion 52a. Alternatively, one surface of the copper plate is etched or anodized to form a porous copper portion 52b having a planar porous shape in which unevenness is dispersed and arranged, and the copper plate is A configuration in which the remainder is the copper plate portion 52a may be used.

The first member 51 and the second member 52 are arranged such that the end surface portion 51c of the bent portion 51a of the first member 51 is the flat surface of the second member 52 so that the internal space 54 is airtightly sealed (preferably vacuum sealed). The end surface portion 51d of the bent portion 51b of the first member 51 is abutted against the flat portion 52d of the second member 52 and joined to the portion 52c. The first member 51 and the second member 52 may be joined by a method using a joining material such as solder or silver solder. A method using thermal diffusion (pressure diffusion bonding) is preferable from the viewpoint of improving the reliability of the bonding. In pressure diffusion bonding, the surfaces to be bonded (the end surface portion 51c and the flat portion 52c) are bonded together by utilizing thermal diffusion generated by heating (heating) the surfaces to be bonded under a load so that they are pressed against each other. , and a method of joining the end face portion 51d and the flat portion 52d). The heating (heat treatment) in this case is preferably performed in a non-oxidizing atmosphere using, for example, nitrogen gas, argon gas, or a mixed gas of nitrogen and argon. Furthermore, it is required to maintain the temperature at 600° C. or higher and 1000° C. or lower.

The internal space 54 of the housing-shaped heat diffusion component 50 is hermetically sealed (preferably vacuum sealed) by the first member 51 and the second member 52 . It should be noted that the members involved in hermetic sealing of the internal space 54 are not limited to the first member 51 and the second member 52, and other members such as heat dissipation terminals (not shown) may be involved. The internal space 54 that is hermetically sealed (preferably decompressed) is used as a heat flow path by sealing a working fluid (refrigerant) therein that enables heat transport by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, CFC alternative, alcohol, or organic compounds such as acetone can be used. From the viewpoint of safety, low cost, ease of handling, etc., it is preferable to use pure water. .

The housing-shaped heat diffusion component 50 has the heat sources 5a and 5b directly or indirectly attached to the upper surface of the first member 51, that is, the flat portions 2a and 2b on the exposed surface of the first copper layer 2. Bondable heat source bond regions 2A, 2B may be provided. Note that the sites where the heat source bonding regions 2A and 2B are provided may be set as required, and are not limited to the surface of the first member 51 . Also, the number of heat sources 5a and 5b may be one, or three or more, and may be, for example, electronic components such as semiconductor elements.

When the housing-shaped heat diffusion component 50 is used, the heat generated by the heat sources 5a and 5b is conducted to the first member 51 in contact with the heat sources 5a and 5b, and the first copper layer 2 from the flat portions 2a and 2b. conducts to the inside of the The heat conducted to the first copper layer 2 is conducted inside the first copper layer 2 in the X, Y and Z directions. The heat conducted in the X direction and the Y direction inside the first copper layer 2 is conducted from the joints 53a and 53b to the second member 52, and is connected to the end of the first member 51 by a heat dissipation terminal (not shown) or the like. is provided, it is released to the outside through it and diffuses, and part of it is released into the air (for example, the atmosphere) from the exposed surface of the first copper layer 2 and diffuses. At the same time, the heat conducted in the Z direction inside the first copper layer 2 is conducted inside the stainless steel layer 3 . The heat conducted to the stainless steel layer 3 is directed toward the second copper layer 4 adjacent to the direction in which the level of thermal energy is low and heat is easily conducted, that is, the Z direction in which the conduction distance is relatively small. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed toward the inner space 54 in which the working fluid (refrigerant), which has a low energy level and is easy to conduct heat, exists inside the second copper layer 4, that is, toward the Z direction. conducts to The heat conducted from the surface of the second copper layer 4 constituting the first member 51 to the working fluid (refrigerant) in the internal space 54 is transported by the working fluid (refrigerant), and the heat dissipation provided at the end of the internal space 54, etc. It is discharged to the outside through a terminal (not shown) or the like. The heat conducted from the first member 51 to the second member 52 is conducted to the working fluid (refrigerant) in the internal space 54 via the porous copper portion 52b and is radiated to the outside and diffused. It is released into the air (eg, into the atmosphere) from the exposed surface of portion 52a and diffuses.

The housing-shaped heat diffusion component 50 has appropriate heat conduction properties due to the copper layers (the first copper layer 2 and the second copper layer 4) and the appropriate mechanical properties due to the stainless steel layer 3, which constitute the first member 51. have As a result, the housing-shaped heat diffusion component 50 can be made thinner by reducing the thickness of the housing (the length in the Z direction). Such a housing-shaped heat diffusion component 50 can be said to be a flat plate-shaped heat pipe with a high heat radiation effect (thermal diffusion effect), and is suitable for use as the housing of the above-described vapor chamber. In addition, the housing-shaped heat diffusion component 50 can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member to be mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to making the devices and devices thinner, more compact, and lighter.

(Modification of the fifth configuration example)
FIG. 10 is a cross-sectional configuration of a housing-like heat diffusion component 50A, which is an embodiment of the heat diffusion component according to the present invention, shown as a modification of the fifth configuration example. The shape, size, ratio, magnification, etc. of each member shown in FIG. 10 are exaggerated and schematic for clarity, and oblique lines representing cross sections are omitted for simplification.

As a modification of the fifth configuration example, a housing-shaped heat diffusion component 50A shown in FIG. and further includes a support portion 55 . The support portion 55 is arranged in the internal space and joined to the second copper layer 4 forming the first member 51 and the copper plate portion 52 a forming the second member 52 . As a result, the mechanical strength of the housing-shaped heat diffusion component 50A is increased, so that the housing-shaped heat diffusion component 50A can be made thinner. In addition, the internal space is divided into two internal spaces 54a and 54b by the support portion 55, and the two internal spaces 54a and 54b can be connected by providing the communication path 55a in the support portion 55. FIG. In this case, the number of connecting passages 55a provided in the support portion 55 is not limited to one, and a plurality of connecting passages 55a may be provided as necessary. In addition, the first member 51 and the second member 52 constituting the heat diffusion component 50A, the method of joining the first member 51 and the second member 52, the heat sources 5a and 5b and the heat source joining regions 2A and 2B, and The description of the working fluid (refrigerant) hermetically sealed (preferably decompressed) in the two internal spaces 54a and 54b is omitted here, and the description of the heat diffusion component 50 described above is referred to.

When the case-shaped heat diffusion component 50A is used, heat generated by the heat sources 5a and 5b is transferred to the first member 51 in contact with the heat sources 5a and 5b, as in the case of the case-shaped heat diffusion component 50 described above. from the planar portions 2a, 2b of the first copper layer 2, the stainless steel layer 3, and the second copper layer 4, most of which is from the exposed surface of the second copper layer 4 to the level of thermal energy in the internal spaces 54a, 55b It conducts to a working fluid (refrigerant) with a low energy, is transported by the working fluid (refrigerant), and is discharged to the outside through heat radiation terminals (not shown) provided at the ends of the internal spaces 54a and 54b. At this time, even if the amount of heat conducted to the working fluid (refrigerant) in the internal space 54a differs from the amount of heat conducted to the working fluid (refrigerant) in the internal space 54b, the working fluid in the internal spaces 54a and 55n The working fluid (refrigerant) can move through the communication path 55a of the support 55 so that the level of thermal energy of the (refrigerant) is balanced. The heat conducted from the first member 51 to the second member 52 is conducted to the working fluid (refrigerant) in the internal spaces 54a and 54b through the porous copper portion 52b, is radiated to the outside, and diffuses. is released from the exposed surface of the copper plate portion 52a into the air (for example, into the atmosphere) and diffuses.

The housing-shaped heat diffusion component 50A has appropriate heat conduction characteristics due to the copper layers (the first copper layer 2 and the second copper layer 4) and appropriate mechanical characteristics due to the stainless steel layer 3, which constitute the first member 51. have Further, the housing-shaped heat diffusion component 50A has a support portion 55 joined to the first member 51 and the second member 52 . As a result, the housing-shaped heat diffusion component 50A is reinforced, and the thickness of the housing (the length in the Z direction) can be further reduced, so that the thickness can be further reduced. Such a case-shaped heat diffusion component 50A is suitable for use as a case of the above-described vapor chamber. In addition, the housing-shaped heat diffusion component 50A can be mounted as a heat diffusion component such as a heat dissipation member or a heat transfer member mounted on small devices and devices such as mobile personal computers and mobile phones. It can also function as a conductive member, chassis, case or frame as required. This can be expected to contribute to further thinning, compactness, and weight reduction of the devices and devices described above.

Next, a composite metal plate for heat diffusion according to the present invention (represented by the composite metal plate 1 shown in FIG. 1) was actually produced and evaluated. Specifically, as shown in Table 1, by changing the thickness ratio (Ts/Tc) of the composite metal plate 1, the mechanical properties of the composite metal plate 1, the heat conduction properties in the X direction and the Z direction (Kx, Kz ), and the anisotropy of thermal conductivity properties (AIS). The thickness ratio is obtained using an optical microscope photograph of a cross section, the mechanical strength (tensile strength, 0.2% yield strength, elongation) is measured in accordance with JIS-Z2241: 2011, and the hardness is JIS- Obtained in accordance with Z2245:2016. Also, the thermal conductivity was obtained by the method described later. The specimens used for various evaluations were cut from the composite metal plate 1 produced by the clad plate material manufacturing method described above using the materials shown in Table 1 into predetermined sizes suitable for various evaluations. The results are shown in Tables 1 and 2, Figures 11, 12 and 13. For comparison with the composite metal plate 1, Tables 1 and 2 also show a single stainless plate (stainless steel layer) and a single copper plate (copper layer).

(Mechanical properties of composite metal plate)
As the mechanical properties of the composite metal plate 1, tensile strength, proof stress (0.2% proof stress, 0.01% proof stress), elongation, and hardness of the stainless steel layer and the copper layer were evaluated.

As shown in Table 2, the tensile strength is 489 MPa to 578 MPa when Ts / Tc is 0.5 (No. 6, 7, 11), and when Ts / Tc is 1.5 (No. 1 to 5) is 558 MPa to 1171 MPa, when Ts / Tc is 2.0 (No. 8, 9, 12), 665 MPa to 856 MPa, and when Ts / Tc is 3.0 (No. 10), 758 MPa Met. As a result, considering that the tensile strength of the composite metal plate 1 can be increased by increasing Ts/Tc from 0.5 to 1.5 or 2.0, for example, and considering Ts/Tc, the stainless steel layer By adjusting the composition (material) of the stainless steel that constitutes 3, the finishing rolling rate to obtain the final thickness (product thickness) of the composite metal plate 1, the presence or absence of heat treatment, and the conditions of heat treatment, etc. It turned out to be selectable.

Further, as shown in Table 2, the yield strength (0.2% yield strength) of the composite metal plate 1 is 453 MPa to 551 MPa when Ts/Tc is 0.5 (Nos. 6, 7, and 11), and Ts/ When Tc is 1.5 (No. 5), it is 222 MPa, when Ts / Tc is 2.0 (No. 8, 9, 12), it is 570 MPa to 675 MPa, and when Ts / Tc is 3.0 In case (No. 10), it was 634 MPa. For reference, the 0.01% yield strength when Ts/Tc of the composite metal plate 1 was 1.5 was from 147 MPa to 1044 MPa. As a result, the proof stress of the composite metal plate 1 is obtained by considering Ts/Tc, the composition (material) of the stainless steel constituting the stainless steel layer 3, and the final thickness (product thickness) of the composite metal plate 1. It was found that a relatively wide range of selection is possible by adjusting the rolling reduction, the presence or absence of heat treatment, and the conditions of heat treatment.

Further, as shown in Table 2, the elongation of the composite metal plate 1 is from 9.0% to 23.3% when Ts/Tc is 0.5 (Nos. 6, 7, and 11). When is 1.5 (No. 1 to 5), it is 0.8% to 1.8%, and when Ts/Tc is 2.0 (No. 8, 9, 12), it is 24.6% to 34 .7% and 39.5% when Ts/Tc is 3.0 (No. 10). As a result, the elongation of the composite metal plate 1 is determined by considering Ts/Tc, the composition (material) of the stainless steel forming the stainless steel layer 3, and the final thickness (product thickness) of the composite metal plate 1. It was found that a relatively wide range of selection is possible by adjusting the rolling reduction, the presence or absence of heat treatment, and the conditions of heat treatment.

Further, as shown in Table 2, the hardness of the stainless steel layer of the composite metal plate 1 is 301 HV to 353 HV when Ts/Tc is 0.5 (Nos. 6, 7, and 11), and Ts/Tc is 2. .0 (Nos. 8, 9 and 12) were 281 HV to 381 HV, and when Ts/Tc was 3.0 (No. 10) it was 274 HV. As a result, the hardness of the stainless copper of the composite metal plate 1 is determined by considering Ts/Tc, the composition (material) of the stainless steel forming the stainless steel layer 3, the final thickness of the composite metal plate 1 (product thickness ), the presence or absence of heat treatment, and the conditions of heat treatment.

Further, as shown in Table 2, the hardness of the copper layer of the composite metal plate 1 is 88 HV to 103 HV when Ts/Tc is 0.5 (Nos. 6, 7, and 11), and Ts/Tc is 2. .0 (Nos. 8, 9 and 12) were 86 HV to 102 HV, and when Ts/Tc was 3.0 (No. 10) it was 89 HV. As a result, the hardness of the stainless copper of the composite metal plate 1 is relatively wide by considering Ts/Tc and adjusting the finish rolling rate to obtain the final thickness (product thickness) of the composite metal plate 1. It turned out to be selectable in the range.

Next, the thermal conductivity Kx in the X direction (plane direction, rolling direction) of the composite metal plate 1 was evaluated. The thermal conductivity Kx in the X direction of the composite metal plate 1 shown in Table 2 and FIG. Based on the thermal conductivity Kc of copper (C1020) forming the copper layer 4, the thickness (Ts) of the stainless steel layer, and the total thickness of the copper layer (Tc=Tc1+Tc2), Kx=Ts×Ks+Tc×Kc asked. Based on the thermal conductivity Kx obtained in this manner, the relationship between Ts/Tc of the composite metal plate 1 and the thermal conductivity Kx in the X direction is summarized in the diagram (graph) shown in FIG.

As shown in FIG. 11, the thermal conductivity Kx of the composite metal plate 1 in the X direction is 340 W/(m K) or less in the range of Ts/Tc of the composite metal plate 1 from 0.2 to 5. It was found that Ts/Tc tends to decrease as Ts/Tc increases (see ◯ and ● in FIG. 11). In addition, the thermal conductivity Kx in the X direction has a large Ts/Tc in the range of 0.2 to 4 (especially 0.2 to 3, particularly 0.2 to 2). It was found that there is a tendency for the degree of decrease with increasing. For example, for a variation of Ts/Tc between 0.2 and 4 (3.8), the thermal conductivity Kx in the X direction varies from about 340 W/(mK) to about 120-100 W/(mK). K) (the amount of change is about 220 to 240 W/(m·K)), and the change gradient is about 58 to 63 (220 to 240/3.8). For example, for a variation of Ts/Tc between 0.2 and 3 (2.8), the thermal conductivity Kx in the X direction is from about 340 W/(mK) to about 120 W/(mK). (the amount of change is about 220 W/(m·K)), and the change gradient is about 80 (220/2.8). For example, for a variation of Ts/Tc between 0.2 and 2 (1.8), the thermal conductivity Kx in the X direction is from about 340 W/(mK) to about 150 W/(mK). (the amount of change is about 190 W/(m·K)), and the change gradient is about 106 (190/1.8).

The change tendency of the thermal conductivity Kx in the X direction with respect to Ts/Tc of the composite metal plate 1 can be expressed by the approximation formula (exponential approximation) indicated by the dashed line in FIG. logarithmic approximation), the relationship between Ts/Tc of the composite metal plate 1 and the thermal conductivity Kx in the X direction can be found appropriately and easily.

Also, the thermal conductivity Kz in the Z direction (thickness direction, plate thickness direction) of the composite metal plate 1 was evaluated. Here, in a metal material (metal layer) having the same configuration, the thermal conductivity in the Z direction with respect to the thermal conductivity in the X direction (assumed to be K) of the metal layer is represented by the reciprocal (1/K). can. Specifically, the thermal conductivity Kz in the Z direction of the composite metal plate 1 shown in Table 2 and FIG. And based on the thermal conductivity Kc of copper (C1020) constituting the second copper layer 4, the thickness (Ts) of the stainless steel layer, and the total thickness of the copper layer (Tc = Tc1 + Tc2), Kz = Ts / Ks + Tc /Kc. Based on the thermal conductivity Kz obtained in this manner, the relationship between Ts/Tc of the composite metal plate 1 and the thermal conductivity Kz in the Z direction is summarized in the diagram (graph) shown in FIG.

As shown in FIG. 12, the Z-direction thermal conductivity Kz of the composite metal plate 1 is 20 W/(m K) or more in the range of Ts/Tc of the composite metal plate 1 from 0.2 to 5. It was found that Ts/Tc tends to decrease as Ts/Tc increases (see ◯ and ● in FIG. 11). In addition, the thermal conductivity Kz in the Z direction becomes large in a range where Ts/Tc is 0.2 or more and 4 or less (especially 0.2 or more and 3 or less, significantly 0.2 or more and 2 or less). It was found that there is a tendency for the degree of decrease with increasing. For example, for a variation of Ts/Tc between 0.2 and 4 (3.8), the thermal conductivity Kz in the Z direction varies from about 50 W/(mK) to about 25-20 W/(mK). K) (the amount of change is about 25 to 30 W/(m·K)), and the change gradient is about 7 to 8 (25 to 30/3.8). For example, for a variation of Ts/Tc between 0.2 and 3 (2.8), the thermal conductivity Kz in the Z direction is about 50 W/(mK) to about 20 W/(mK). (the amount of change is about 30 W/(m·K)), and the change gradient is about 11 (30/2.8). For example, for a variation of Ts/Tc between 0.2 and 2 (1.8), the thermal conductivity Kz in the Z direction is about 50 W/(mK) to about 25 W/(mK). (the amount of change is about 25 W/(m·K)), and the change gradient is about 14 (25/1.8). From this point of view, it was found that the change gradient of the thermal conductivity Kz in the Z direction is about 1/6 that of the thermal conductivity Kx in the X direction.

The trend of change in thermal conductivity Kz in the Z direction with respect to Ts/Tc of the composite metal plate 1 can be determined by the approximation formula (exponential approximation) indicated by the dashed line in FIG. logarithmic approximation), the relationship between Ts/Tc of the composite metal plate 1 and the thermal conductivity Kz in the Z direction can be found appropriately and easily.

Also, using the thermal conductivities Kx and Kz in the X and Z directions of the composite metal plate 1 described above, the ratio of the thermal conductivity in the Z direction to the X direction of the composite metal plate 1 (Kx/Kz), that is, the composite metal plate The anisotropy of thermal conductivity (AIS) of No. 1 was evaluated. The relationship between Ts/Tc of the composite metal plate 1 and AIS representing the anisotropy of thermal conductivity properties is summarized in the diagram (graph) shown in FIG.

As shown in FIG. 13, the anisotropy (AIS) of the thermal conductivity characteristics of the composite metal plate 1 is determined by AIS, that is, Kx/Kz, in the range of Ts/Tc of the composite metal plate 1 from 0.2 to 5. The upper limit of the thermal conductivity ratio is 4.4 and the lower limit is 8.8, that is, the AIS is 4.4 or more and 6.8 or less, and Ts/Tc tends to decrease as it increases. was made. Then, the change tendency of the anisotropy of thermal conductivity (AIS) with respect to Ts/Tc of the composite metal plate 1 can be expressed with high reliability by the approximation formula (linear approximation) indicated by the dotted line in FIG. 13, and the change The slope could be found to be on the order of -0.49. From this, the anisotropy (AIS) of the thermal conductivity characteristics of the composite metal plate 1 is such that when the Ts/Tc of the composite metal plate 1 is in the range of 0.2 to 5, the thickness (Ts) of the stainless steel layer 3 is large. Then, in other words, when the thickness (Tc) of the copper layer is reduced, it has been found that the anisotropy is weakened. This is because by increasing the Ts/Tc of the composite metal plate 1 to weaken the anisotropy of the heat conduction characteristics (reduce the AIS), the heat diffusivity in the X direction of the composite metal plate 1 is relatively weakened. This means that it is possible to perform an operation that enhances thermal diffusivity in the Z direction. Alternatively, by decreasing the Ts/Tc of the composite metal plate 1 to strengthen the anisotropy of the thermal conductivity characteristics (increasing the AIS), the heat diffusivity in the X direction of the composite metal plate 1 is relatively strengthened. , means that an operation that weakens thermal diffusivity in the Z direction is possible.

By utilizing the anisotropy (AIS) of the heat conduction characteristics of the composite metal plate 1, for example, the heat dissipation part that releases the heat released from the heat source to the outside is the X of the heat diffusion component using the composite metal plate 1. In the case of being arranged at the side end of the direction, the composite metal plate 1 used for the heat diffusion part is operated so as to decrease Ts/Tc (increase AIS), so that the heat in the X direction It is preferable to configure the composite metal plate 1 with enhanced diffusivity. Further, for example, in the case where a heat radiating part that radiates heat released from a heat source to the outside is arranged at the side edge in the Z direction of the heat diffusion component using the composite metal plate 1, the heat diffusion component It is preferable to configure the composite metal plate 1 with enhanced thermal diffusivity in the X direction by operating the composite metal plate 1 to be used so that Ts/Tc is increased (AIS is decreased).

As described above, the relationship between the Ts/Tc of the composite metal plate 1 and the mechanical properties, the relationship between the Ts/Tc of the composite metal plate 1 and the thermal conductivity Kx in the X direction, and the Ts/Tc of the composite metal plate 1 and the thermal conductivity Kz in the Z direction, the ratio of the thermal conductivity in the X direction and the Z direction to Ts / Tc of the composite metal plate 1 (Kx / Kz), that is, the anisotropic (AIS) in the thermal conductivity characteristics We were able to clarify the relationships and the gradient of change in each relationship. As a result, considering the relationship between the above-described mechanical properties and thermal conductivities Kx and Kz with respect to Ts/Tc of the composite metal plate 1, a composite metal plate having an anisotropic thermal conductivity (AIS) suitable for the application 1 can now be found appropriately and easily.

As a result, in various heat diffusion applications, the required properties (for example, mechanical properties) other than heat conduction properties are generally different depending on the application, but the first copper layer, the stainless steel layer, and the second copper layer The thickness ratio (Ts/ Considering the relationship between Tc) and the ratio of thermal conductivity in the X direction and the Z direction (Kx/Kz) of the composite metal plate for heat diffusion, that is, the anisotropy of thermal conductivity (AIS), various thermal diffusion It has become possible to appropriately and easily find a configuration suitable for the application.

TECHNICAL FIELD The present invention relates to a composite metal plate having a total thickness of 500 μm or less, in which stainless steel layers and copper layers are alternately bonded, and which is used, for example, as a conductive member, a heat radiating member, a chassis, a case and a frame. It has industrial applicability in that it makes it possible to find a sheet appropriately and simply according to the required properties of the application, and that it is possible to easily provide a composite metal sheet suitable for various uses.

1. Composite metal plate2. First copper layer, 2a. flat portion, 2b. plane, 2A. heat source junction area, 2B. 2. heat source junction area; stainless steel layer4. Second copper layer 5a. heat source, 5b. Heat source X: planar direction (rolling direction, longitudinal direction)
Y: planar direction (rolling width direction, width direction)
Z: thickness direction (thickness direction)
<Figure 2>
10. Heat spreading parts 11 . First member <Figs. 3 and 4>
20. heat spreader, 20A. Heat spreading parts 21 . First member 21a. bend 21b. bend 21c. end face 21d. end surface 22 . Second member 22a. bend 22b. bend 22c. end face 22d. End surface 23a. junction, 23b. junction 24 . Internal space (heat flow path), 24a. Internal space (heat flow path), 24b. Internal space (heat flow path)
25. support, 25a. Connecting path <Fig. 5, Fig. 6>
30. heat spreading components, 30A. Heat spreading parts 31 . First member 31a. bend 31b. bend 31c. end face, 31d. end surface 32 . Second member 32a. flat portion, 32b. Flat portion 33a . junction, 33b. junction 34 . Internal space (heat flow path), 34a. Internal space (heat flow path), 34b. Internal space (heat flow path)
35. support, 35a. Connecting path <Fig. 7, Fig. 8>
40. heat spreading components, 40A. Heat spreading parts 41 . First member 41a. bend, 41b. bend 41c. flat portion, 41d. Flat portion 42 . Second member 42a. copper plate portion, 42b. Porous copper portion, 42c. end face 42d. End face portion 43a. junction, 43b. junction 44 . Internal space (heat flow path), 44a. Internal space (heat flow path), 44b. Internal space (heat flow path)
45. support, 45a. Connecting path <Figs. 9 and 10>
50. heat spreader, 50A. Heat spreading parts 51 . First member 51a. bend, 51b. bend, 51c. end face, 51d. end face portion 52 . Second member 52a. copper plate portion, 52b. Porous copper portion, 52c. flat portion, 52d. Planar portion 53a . junction, 53b. junction 54 . Internal space (heat flow path), 54a. Internal space (heat flow path), 54b. Internal space (heat flow path)
55. support, 55a. connecting road

Claims (9)

A housing-like heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer,
The total thickness is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the stainless steel layer where Ts is the thickness of the second copper layer and Tc2 is the thickness of the second copper layer, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the heat in the plane direction of the composite metal plate Where Kx is the conductivity and Kz is the thermal conductivity in the thickness direction of the composite metal plate, the thermal conductivity ratio determined by Kx/Kz is 4.4 or more and 6.8 or less. A first member made of a composite metal plate, a second member made of the composite metal plate for heat diffusion, and an internal space,
The bent portion on the one end side of the first member and the bent portion on the one end side of the second member are joined, and the bent portion on the other end side of the first member and the bent portion on the other end side of the second member are joined. and the internal space is airtightly sealed by joining the parts. A housing-like heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer,
The total thickness is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the stainless steel layer where Ts is the thickness of the second copper layer and Tc2 is the thickness of the second copper layer, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the heat in the plane direction of the composite metal plate Where Kx is the conductivity and Kz is the thermal conductivity in the thickness direction of the composite metal plate, the thermal conductivity ratio determined by Kx/Kz is 4.4 or more and 6.8 or less. A first member made of a composite metal plate, a second member made of the composite metal plate for heat diffusion, and an internal space,
The bent portion on the one end side of the first member and the flat portion on the one end side of the second member are joined together, and the bent portion on the other end side of the first member and the flat surface on the other end side of the second member are joined. and the internal space is airtightly sealed by joining the parts. A housing-like heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer,
The total thickness is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the stainless steel layer where Ts is the thickness of the second copper layer and Tc2 is the thickness of the second copper layer, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the heat in the plane direction of the composite metal plate Where Kx is the conductivity and Kz is the thermal conductivity in the thickness direction of the composite metal plate, the thermal conductivity ratio determined by Kx/Kz is 4.4 or more and 6.8 or less. A first member made of a composite metal plate, a second member made of a copper plate portion, and an internal space,
The bent portion on the one end side of the first member and the end face portion on the one end side of the second member are joined together, and the bent portion on the other end side of the first member and the end face on the other end side of the second member are joined. and the internal space is airtightly sealed by joining the parts. 4. The heat diffusion component according to claim 3 , further comprising a porous copper layer adjacent to said copper plate portion on said inner space side of said second member. A housing-like heat diffusion component using a heat diffusion composite metal plate having a first copper layer, a stainless steel layer, and a second copper layer,
The total thickness is 500 μm or less, the first copper layer, the stainless steel layer, and the second copper layer are bonded in this order, the thickness of the first copper layer is Tc1, and the stainless steel layer where Ts is the thickness of the second copper layer and Tc2 is the thickness of the second copper layer, the thickness ratio determined by Ts/(Tc1+Tc2) is 0.2 or more and 5 or less, and the heat in the plane direction of the composite metal plate Where Kx is the conductivity and Kz is the thermal conductivity in the thickness direction of the composite metal plate, the thermal conductivity ratio determined by Kx/Kz is 4.4 or more and 6.8 or less. A first member made of a composite metal plate, a second member made of a copper plate portion, and an internal space,
The bent portion on the one end side of the first member and the flat portion on the one end side of the second member are joined together, and the bent portion on the other end side of the first member and the flat surface on the other end side of the second member are joined. and the internal space is airtightly sealed by joining the parts. 6. The heat diffusion component according to claim 5 , further comprising a porous copper layer adjacent to said copper plate portion on said inner space side of said second member. Any one of claims 1, 2, 3 and 5, wherein said composite metal plate for heat diffusion is used, wherein said Kx is 340 W/(m·K) or less and said Kz is 20 W/(m·K) or more. 1. The heat diffusion component according to claim 1. The first copper layer and the second copper layer are composed of pure copper containing 99% by mass or more of Cu, or composed of a copper alloy having a higher thermal conductivity than the stainless steel that constitutes the stainless steel layer. 6. The heat diffusion part according to any one of claims 1, 2, 3 and 5, wherein said composite metal plate for heat diffusion is used. The stainless steel layer is, in mass%, 10.5% or more and 30% or less of Cr, 0.6% or more and 25% or less of Ni, 0.20% or less of C, and the balance of Fe and unavoidable impurities. 6. The heat diffusion part according to any one of claims 1, 2, 3 and 5, wherein said heat diffusion composite metal plate made of steel is used.

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