JP2020025097A - Heat diffusion composite metal sheet and heat diffusion part - Google Patents

Abstract

To appropriately and easily provide a heat diffusion composite metal plate applicable to an application whose main purpose is to release heat of a heating element to the outside of a heating element, and a heat diffusion component using the same according to the required characteristics of the application.SOLUTION: In a heat diffusion composite metal plate, the total thickness is 500 μm or less, 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, and when the thermal conductivity in the plane direction is Kx, and the thermal conductivity in the thickness direction is Kz, the thermal conductivity ratio determined by Kx/Kz is 4.4 or more and 6.8 or less. A plate-like or housing-like heat diffusion component is constituted by using the composite metal plate for heat diffusion.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composite metal plate for thermal diffusion and a component for thermal diffusion, for example, a composite metal plate for thermal diffusion applicable to an application whose main purpose is to release heat of a heating element to the outside of the heating element, particularly, The present invention relates to a heat diffusion composite metal plate having a total thickness of 500 μm or less, in which a copper layer and a stainless steel layer are alternately joined, and a heat diffusion component using the heat diffusion composite metal plate. In the present invention, a composite metal plate having an overall thickness of 100 μm or less is particularly referred to as a “composite metal foil”, and a composite metal plate having an overall thickness of 50 μm or less is particularly referred to as a “composite metal thin foil”. May be called.

  2. Description of the Related Art Conventionally, a composite metal plate in which a copper plate (copper layer) and a stainless steel plate (stainless steel layer) are joined has been used in a heat diffusion application whose main purpose is to release heat of the heating element to the outside of the heating element. I have. For example, Patent Literature 1 discloses a plate heat exchanger in which a plurality of heat transfer plates having continuous uneven surfaces are stacked. This heat transfer plate is a composite metal plate for heat diffusion (cladding plate material) having a three-layer structure in which a copper plate is joined to both sides of a stainless steel plate. A component formed by using the composite metal plate and having a plurality of stacked heat transfer plates is a heat diffusion component that can release the heat of the heat source using heat conduction to the heat transfer plate. .

  Further, for example, Patent Document 2 discloses a vapor chamber formed of a flat container (housing) in which a pair of opposed plate members are joined and integrally formed. The pair of plate members constituting the casing of the vapor chamber are each a composite metal plate for heat diffusion (cladding plate member) having a two-layer structure in which a copper plate and a stainless steel plate are joined. In the casing of the vapor chamber, a working fluid such as water, CFC alternative, or alcohol capable of transporting heat in the form of latent heat is depressurized and sealed (sealed) in the internal space. The casing of the vapor chamber is a heat diffusion component capable of releasing the heat of the heat source to the outside using heat conduction to the plate material and the working fluid. It is stated that the composite metal plate for heat diffusion may be a three-layer composite metal plate (cladding plate material) in which the front and back surfaces of a stainless steel plate are sandwiched between copper plates.

JP 2005-134073 A JP-A-2006-188734

  The composite metal plate for heat diffusion disclosed in Patent Literature 1 is bent to form an uneven surface and brazed in an electric furnace. Further, a pair of composite metal plates for heat diffusion constituting a casing of a vapor chamber disclosed in Patent Document 2 are bent to form a casing, and are welded or welded to each other to prevent leakage of a working fluid. It is considered that they are joined by brazing or the like. Each of the composite metal sheets for heat diffusion has appropriate heat conduction characteristics for heat diffusion, and unlike metal sheets (single sheets) made of a single metal material, copper sheets (copper layers) and stainless steel The steel plate (stainless steel layer) has appropriate mechanical properties to enable plastic deformation without peeling, and is 700 ° C or more (silver brazing, etc.) or 1000 ° C or more (copper brazing, It is necessary to have appropriate heat-resistant properties applicable to high temperature or partial melting by welding.

  However, Patent Literature 1 and Patent Literature 2 do not disclose an appropriate composition of a copper layer (copper plate) and a stainless steel layer (stainless steel plate) constituting the composite metal plate for heat diffusion, and disclose an overall thickness of the composite metal plate. The thicknesses of the copper layer and the stainless steel layer and the thickness ratio of the copper layer and the stainless steel layer are not disclosed. Since specific information considered necessary for practical use has not been disclosed, a composite metal plate for heat diffusion constituting a heat transfer plate disclosed in Patent Document 1 and a casing of a vapor chamber disclosed in Patent Document 2 have been disclosed. It is not limited to a pair of composite metal sheets for heat diffusion that make up the body, but the necessary properties of composite metal sheets for thermal diffusion suitable for the desired application, especially the balance between the mechanical properties and the heat conduction properties of the composite metal sheets for thermal diffusion In addition, the directional characteristics of the heat conduction characteristics could not be found appropriately and simply.

  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 a copper layer and a stainless steel layer are alternately joined, for example, by transferring the heat of the heating element to the outside of the heating element. Characteristics required for the composite metal sheet for heat diffusion applicable to the application whose main purpose is to escape to the environment, in particular, the balance between mechanical properties and thermal conductivity properties, and the directional properties of thermal conductivity properties (ratio of thermal conductivity) It is possible to easily and easily find a composite metal plate for heat diffusion suitable for various uses, and easily provide a component for thermal diffusion using the composite metal plate for heat diffusion. Is to do so.

  The present inventor has studied necessary characteristics suitable for a desired application of heat diffusion in a conventional composite metal plate for heat diffusion (cladding plate material). With respect to the balance and the directional characteristics of heat conduction characteristics (ratio of heat conductivity), the inventors have found means capable of solving the above-described problems, and have arrived at the present invention.

  The 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. 1 When the thickness of the 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 not less than 0.2 and not more than 5. When the thermal conductivity in the plane direction of the composite metal plate is Kx and the thermal conductivity in the thickness direction of the composite metal plate is Kz, the ratio of the thermal conductivity determined by Kx / Kz is 4.4 or more. 8 or less.

  In the composite metal plate for thermal diffusion according to the present invention, Kx may be 340 W / (m · K) or less, and Kz may be 20 W / (m · K) or more.

  In the composite metal plate for heat diffusion according to the present invention, the first copper layer and the second copper layer are made of pure copper in which 99% by mass or more of Cu is used, or have a higher thermal conductivity than the stainless steel constituting the stainless steel layer. Is preferably made of a copper alloy having a large value.

  In the composite metal plate for heat diffusion according to the present invention, in the stainless steel layer, 1% to 30% of Cr, 0.6% to 25% of Ni, and 0.20% or less of It is preferable to be composed of stainless steel composed of C and the balance Fe and unavoidable impurities.

  A component for heat diffusion can be constituted by using any one of the composite metal plates for heat diffusion according to the present invention.

  A heat diffusion component according to the first aspect of the present invention is a flat heat diffusion component using a heat diffusion composite metal plate having any one of the above-described first copper layer, stainless steel layer, and second copper layer. A component, comprising a first member made of a composite metal plate for heat diffusion, wherein a heat source is directly or indirectly joined to a flat portion of the first member made of a first copper layer or a second copper layer. Provide a possible heat source junction area.

  A heat diffusion component according to a second aspect of the present invention is a housing-like heat diffusion component using a heat diffusion composite metal plate having any one of the above-described first copper layer, stainless steel layer, and second copper layer. A first member made of a composite metal plate for heat diffusion, a second member made of a composite metal plate for heat diffusion, and an internal space, and one end of the first member. The bent portion and the bent portion on 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 to form the internal space. Are hermetically sealed.

  A heat-diffusion component according to a third aspect of the present invention is a housing-like heat-diffusion using a heat-diffusion composite metal plate having any one of the above-described first copper layer, stainless steel layer, and second copper layer. A first member made of a composite metal plate for heat diffusion, a second member made of a composite metal plate for heat diffusion, and an internal space, and one end of the first member. The internal space is formed by joining the bent portion and the flat portion on one end side of the second member, and 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. Are hermetically sealed.

  A heat diffusion component according to a fourth aspect of the present invention is a case-like heat diffusion component using a heat diffusion composite metal plate having any one of the above-described first copper layer, stainless steel layer, and second copper layer. A first member made of a composite metal plate for heat diffusion, a second member having a copper plate portion, and an internal space, and bending at one end of the first member. The inner space is joined by joining the portion and the end face on one end of the second member, and joining the bent portion on the other end of the first member and the end face on the other end of the second member. Hermetically sealed. Further, it is preferable that a porous copper layer adjacent to the copper plate is provided on the inner space side of the second member.

  A heat-diffusion component according to a fifth aspect of the present invention is a case-shaped heat-diffusion composite metal plate having any one of the above-described first copper layer, stainless steel layer, and second copper layer. A first member made of a composite metal plate for heat diffusion, a second member having a copper plate portion, and an internal space, and bending at one end of the first member. The inner space is joined by joining the portion and the flat portion on one end side of the second member, and 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. Hermetically sealed. Further, it is preferable that a porous copper layer adjacent to the copper plate is provided on the inner space side of the second member.

  According to the present invention, for a heat diffusion composite metal plate having a total thickness of 500 μm or less, in which a copper layer and a stainless steel layer are alternately joined, for example, heat of the heating element is released to the outside of the heating element. Suitable and easy to find out the necessary characteristics of the composite metal sheet for heat diffusion applicable to the application whose main purpose is, especially the balance between mechanical characteristics and heat conduction characteristics and the directional characteristics of heat conduction characteristics . Thereby, a composite metal plate for heat diffusion suitable for various uses can be easily provided, and a component for thermal diffusion using the composite metal plate for heat diffusion can be easily provided.

It is a figure which shows typically the layer structure of one Embodiment of the composite metal plate for thermal diffusion which concerns on this invention. It is a figure which shows typically the structure (1st structural example) of one Embodiment of the component for heat diffusion by the 1st aspect of this invention. It is a figure which shows typically the structure (2nd structural example) of one Embodiment of the component for heat diffusion by the 2nd aspect of this invention. It is a figure which shows typically the structure (modification of 2nd structural example) of one Embodiment of the component for heat diffusion by the 2nd aspect of this invention. It is a figure which shows typically the structure (third example of a structure) of one Embodiment of the component for heat diffusion by the 3rd aspect of this invention. It is a figure which shows typically the structure (modification of 3rd structural example) of one Embodiment of the component for heat diffusion by the 3rd aspect of this invention. It is a figure which shows typically the structure (fourth structural example) of one Embodiment of the component for heat diffusion by the 4th aspect of this invention. It is a figure which shows typically the structure (modification of 4th structural example) of one Embodiment of the component for heat diffusion by the 4th aspect of this invention. It is a figure which shows typically the structure (fifth structure example) of one Embodiment of the component for heat diffusion by the 5th aspect of this invention. It is a figure which shows typically the structure (modification of 5th structural example) of one Embodiment of the component for heat diffusion by the 5th aspect of this invention. About 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) to the thickness of the stainless steel layer (TS) and the plane direction (rolling) FIG. 3 is a diagram (graph) showing a relationship with a thermal conductivity (Kx) in a direction (X direction). About 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) to the thickness of the stainless steel layer (Ts) and the cross-sectional direction (thickness) FIG. 4 is a diagram (graph) showing a relationship with a thermal conductivity (Kz) in a vertical direction (Z direction). It is a figure (graph) which shows the relationship between thickness ratio (Ts / Tc) and heat conduction ratio (Kx / Kz) about one Embodiment of the composite metal plate for thermal diffusion which concerns on this invention.

  The 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. 1 When the thickness of the 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 not less than 0.2 and not more than 5. When the thermal conductivity in the plane direction of the composite metal plate is Kx and the thermal conductivity in the thickness direction of the composite metal plate is Kz, the ratio of the thermal conductivity determined by Kx / Kz is 4.4 or more. 8 or less. Thereby, the necessary properties of the composite metal sheet for heat diffusion suitable for the desired application of heat diffusion, in particular, the balance between the mechanical properties and the heat conduction properties of the composite metal sheet for heat diffusion, and the directional properties ( The composite metal plate for thermal diffusion has a configuration that allows an appropriate and simple finding of the anisotropy of the thermal conductivity characteristics (ie, the ratio of the conductivity).

  Hereinafter, an embodiment of a composite metal plate for heat diffusion according to the present invention and a configuration example 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. .

When describing the composite metal plate for thermal diffusion and the component for thermal diffusion according to the present invention, the following notation is 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 ・ Total thickness of composite metal plate: T
-Thickness of first copper layer: Tc1
-Thickness of second copper layer: Tc2
The total thickness of the first copper layer and the second copper layer: Tc (= Tc1 + Tc2)
・ Stainless steel layer thickness: Ts
· Plane direction (representative) of composite metal plate: X direction (corresponding to rolling direction)
-Plane direction of composite metal plate: Y direction (corresponding to rolling width direction)
・ Thickness direction of composite metal plate: Z direction (corresponding to the rolled plate thickness direction)
-Thermal conductivity in the X direction of the composite metal plate: Kx
・ The thermal conductivity in the Y direction of the composite metal plate: Ky
-Thermal conductivity in the Z direction of the composite metal plate: Kz
-Ratio of thermal conductivity of composite metal plate: AIS (= Kx / Kz)

  In the present invention, the above-mentioned "AIS" is introduced as an index indicating the anisotropy of the heat conduction characteristics in the X direction and the Z direction of the composite metal plate for thermal diffusion. The AIS is obtained by dividing Kx (W / (m · K)) of the composite metal plate measured in a predetermined temperature range by Kz (W / (m · K)) measured in the same temperature range. . When the composite metal plate has isotropic properties in the X direction and the Y direction, Kx and Ky have substantially the same value. For example, a metal plate made of a single material is generally isotropic, and therefore has an AIS of about 1. On the other hand, a metal having a low thermal conductivity (for example, about 16 W / (m · K) is provided between a pair of metal layers having a high thermal conductivity (for example, pure copper of about 370 W / (m · K)). In the case of a composite metal plate having an intermediate layer made of SUS304 and SUS630 of K), SUS430 of about 26 W / (m · K), and the like, Kx is much larger than Kz, so Anisotropy occurs and the AIS becomes a very large value.

  FIG. 1 is a diagram schematically showing a layer configuration of one embodiment of a composite metal plate for heat diffusion according to the present invention. In the composite metal plate 1 shown in FIG. 1, T is 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 thermal diffusion has, for example, heat conduction properties applicable to an application whose main purpose is to release heat of the heating element to the outside of the heating element, and has mechanical properties suitable for the application. Should. From this viewpoint, the composite metal plate 1 preferably has a T of 200 μm or less, more preferably has a T of 100 μm or less, as long as the required properties such as heat conduction characteristics and mechanical characteristics of the application are satisfied. 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 to be different depending on its use, 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, may be 50 μm or more and 100 μm or less, and may be 10 μm or more and 50 μm or less.

  As the composite metal plate 1 has a smaller T, for example, as a heat diffusion member such as a heat dissipating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone, or as a heat diffusion component The use can contribute to a further reduction in weight and size of small devices and apparatuses. The composite metal sheet for heat diffusion according to the present invention is suitable for use in heat diffusion, but may be used for applications other than heat diffusion, for example, as a conductive member, a chassis, a component such as a case or a frame. is there.

  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 the 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 such a configuration, the upper and lower surfaces of the stainless steel layer 3 having poor wettability are covered with the copper layer having good wettability in consideration of the material of the copper layer. Attachment and the like can be easily performed. Further, in consideration of the material of the copper layer, the front and back surfaces of the stainless steel layer 3 having a lower thermal conductivity than the copper layer are covered with the copper layer having a high thermal conductivity. Compared to a plate or a composite metal plate having an excessively small Tc (copper layer / stainless steel layer / copper layer), it can have favorable heat conduction characteristics in any of the X direction, the Y direction, and the Z direction. In particular, it is possible to have more favorable heat conduction characteristics in the X direction and the Y direction. Considering the material of the stainless steel layer 3, the stainless steel layer 3 having a large mechanical strength allows the central portion of the copper layer having a lower mechanical strength than the stainless steel layer 3 (the first copper layer 2 and the second copper layer). 4) is reinforced, so that the X direction and the Y direction are compared with a copper plate made of a single pure copper or a composite metal plate (copper layer / stainless steel layer / copper layer) having an excessively small Ts. And in both the Z and Z directions.

  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, it is possible to have a favorable heat conduction characteristic in the Z direction, as compared with a configuration having a larger Ts / Tc, and also to have a favorable thermal conduction characteristic as a whole. Can be on the standard. Further, the composite metal plate 1 can have preferable mechanical characteristics by configuring Ts / Tc to be larger. From this viewpoint, the composite metal plate 1 having a Ts / Tc of 0.2 or more is a composite metal plate having an excessively small Ts (copper layer / stainless steel layer / copper) as compared with a copper plate made of a single pure copper. Layer) can have favorable mechanical properties. On the other hand, the composite metal plate 1 having Ts / Tc of 5 or less is compared with a stainless steel plate made of a single stainless steel plate or a composite metal plate having an excessively small Tc (copper layer / stainless layer / copper layer). As compared with the case, the heat conduction characteristics can be improved. When Ts / Tc is less than 0.2, the mechanical properties of the composite metal plate become insufficient, and when Ts / Tc exceeds 5.0, the heat conduction characteristics of the composite metal plate become insufficient.

  As 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. In this case, Ts / Tc 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 Kx / Kz in the X direction and the Z direction of 4.4 or more and 6.8 or less. Thereby, the composite metal plate 1 can have heat conduction characteristics suitable for a desired application of heat diffusion, and can have mechanical characteristics suitable for the application. The balance is favorable. Further, the composite metal plate 1 having Kx / Kz, that is, AIS of 4.4 or more and 6.8 or less has directional properties of heat conduction properties, that is, anisotropy, but is not suitable for general heat diffusion applications. Is an applicable level, and it is easy to select anisotropy of the heat conduction characteristic suitable for the use.

  As described above, a desired application of heat diffusion, for example, as a heat diffusion member such as a heat dissipating member mounted on small devices and devices such as mobile personal computers and mobile phones, or as a heat diffusion member, or as a heat diffusion component. In order to appropriately and simply select a composite metal plate for heat diffusion suitable for use, the composite metal plate 1 having the above-described configuration is preferable.

  One method of selecting the composite metal plate 1 using Ts / Tc is to first select Ts / Tc, and then illuminate the graphs shown in FIGS. It is simple to select a composite metal plate 1 that satisfies the characteristics, that is, the heat conduction characteristics (Kx, Kz) and the degree of anisotropy of the heat conduction characteristics (AIS). Alternatively, first, necessary characteristics (Kx, Kz, AIS, etc.) are selected, and then the composite metal plate 1 satisfying Ts / Tc according to the application is obtained by illuminating graphs shown in FIGS. The selection method is simple. By the method of selecting the composite metal plate 1 using Ts / Tc, the configuration of the composite metal plate 1 suitable for various applications of heat diffusion can be appropriately and easily found.

  The composite metal plate 1 may have Kx of 340 W / (m · K) or less and Kz of 20 W / (m · K) or more. In the case of a composite metal plate having Kx exceeding 340 W / (m · K), the respective materials of the first copper layer 2, the stainless steel layer 3, and the second copper layer 4 constituting the composite metal plate are considered in light of practical use. , Ts / Tc becomes less than 0.2, the effectiveness of the stainless steel layer is substantially lost, and it may not be possible to have mechanical properties suitable 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 and second copper layers, It may not be possible to have heat transfer properties suitable for the desired application of heat diffusion.

The first copper layer 2 and the second copper layer 4 that constitute the composite metal plate 1 are made of pure copper containing 99% by mass or more of Cu (element), or are more thermally conductive than the stainless steel that constitutes the stainless steel layer 3. It is preferable to be made of a copper alloy having a high rate. In this case, elements other than Cu contained in the pure copper are inevitable impurities. Specifically, when pure copper is used for the copper layer, it is preferable to use a material having a high thermal conductivity, such as oxygen-free copper, phosphorous deoxidized copper, and tough pitch copper, belonging to the category of C1000 (JIS standard). When a copper alloy is used for the copper layer, it is preferable that the copper alloy belongs to the category of C2000 series (JIS standard) having a relatively high thermal conductivity. Other copper alloys containing Zr (zirconium) in an amount of 0.05% by mass or more and 0.15% by mass or less of C1510 (JIS standard) in order to suppress the coarsening of the crystal of the copper layer. It is also possible to use, for example, those containing Ti (titanium) of 4 ppm or more and 55 ppm or less, S (sulfur) of 2 ppm or more and 12 ppm or less, and O (oxygen) of 2 ppm or more and 30 ppm or less. Since the copper alloy containing Zr has appropriate thermal conductivity and mechanical strength, it can be expected that the copper layer constituting the composite metal plate is reduced in thickness. The copper alloy containing a small amount of Ti or the like has appropriate thermal conductivity characteristics, and TiO, TiO ₂ , TiS, Ti—O—S, and the like are present in the form of a compound or agglomerate, and Ti or S is a solid solution. Therefore, the mechanical properties of the copper layer can be expected to be improved.

  Here, the first copper layer 2 and the second copper layer 4 do not need to be made of the same material, but are preferably made of the same material. The same material refers to the case where the composition of the first copper layer 2 and the composition of the second copper layer 4 are substantially the same (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 at the time of rolling is the same or within a predetermined range (variation)), and both the cases. For example, when the composite metal plate 1 is manufactured 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 and the like.

  The stainless steel layer 3 constituting the composite metal plate 1 is composed of, by mass%, 10.5% to 30% of Cr (chromium), 0.6% to 25% of Ni (nickel), and 0.20% It is preferable to be composed of the following C (carbon) and stainless steel containing 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 made of austenitic stainless steel or precipitation hardened by containing 0.6% or more and 25% or less of Ni and 0.20% or less of C. It can have characteristics (materials) characteristic of stainless steel. The stainless steel constituting the stainless steel layer 3 may be a general stainless steel as defined in the ISO standard or the JIS standard, and may be a specific series such as austenitic, ferritic, martensitic or precipitation hardening. Not limited. According to the ISO standard (ISO-15510), a steel containing 1.2% by mass or less of C and 10.5% by mass or more of Cr is defined as stainless steel. According to the JIS standard (JIS-G0203), an alloy steel containing the same amount of C and Cr as the ISO standard and having improved corrosion resistance is defined as stainless steel.

  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. Stainless steel having a composition containing, for example, 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. The SUS layer made of such stainless steel can have various characteristics characteristic of any of austenitic stainless steels of SUS301, SUS304, SUS305, SUS310S, SUS316 and SUS316L (above, JIS standard). For example, when the composite metal plate 1 is applied to a heat diffusion component of a device or an apparatus including an electronic component such as a semiconductor element, it may not be preferable for the heat diffusion component to be magnetic. In such a case, the stainless steel constituting the stainless steel layer 3 is preferably an austenitic stainless steel, more preferably a SUS300 (JIS standard) austenitic stainless steel, and even more preferably a stainless steel. SUS316L (JIS standard), which has a low content and is less likely to take on magnetism. In addition, SUS316L is 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 by mass%. Austenitic stainless steel made of Fe and unavoidable impurities.

  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 steel layer 3 made of such stainless steel has a Cu content of 2% or more and 5% or less (preferably 3% or more and 5% or less) and a 0.1% or more and 0.5% or less (preferably 0.15% or more and 0% or less). .45% or less), it is possible to have a characteristic (material) characteristic of SUS630 (JIS standard) of precipitation hardening stainless steel by further containing Nb (niobium), or 0.5% or more and 2% or less. By further containing Al (preferably 0.75% or more and 1.5% or less), a characteristic (material) characteristic of SUS631 (JIS standard) of precipitation hardening stainless steel can be obtained.

  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 Or a technician related to clad rolling, comprising: a clad rolling step of rolling a second copper plate made of a copper alloy in a state of being stacked in this order and joining the layers, and a step of performing diffusion annealing after the clad rolling. Can be produced by a method of manufacturing a clad plate material, which is well known. In the method for manufacturing the clad sheet material (composite metal sheet 1) described above, the clad rolling step may include a softening step (softening annealing) of the material to be rolled (plate material), or a predetermined thickness after the step of performing diffusion annealing. Rolling (finish rolling) to form the composite metal plate 1 having a thickness (plate thickness) may be included.

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

(First configuration example)
FIG. 2 shows a layer configuration of a plate-shaped heat diffusion component 10 which is an embodiment of the heat diffusion component according to the present invention and is shown as a first configuration example. Note that the shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 2 are exaggerated and schematic for clarity.

  As a first configuration example, a plate-shaped heat diffusion component 10 shown in FIG. 2 includes a first member 11. The first member 11 is made of the composite metal plate 1 (first copper layer 2) having T of 500 μm or less, Ts / Tc of 0.2 or more and 5 or less, and Kx / Kz of 4.4 or more and 6.8 or less. / Stainless steel layer 3 / second copper layer 4).

  The heat-dissipating sources 10 a and 5 b are directly or indirectly joined to the upper surface of the first member 11, that is, the flat portions 2 a and 2 b on the exposed surface of the first copper layer 2. Possible heat source bonding regions 2A and 2B are provided. The number of heat sources 5a and 5b may be any one, or may be three or more, and may be, for example, an electronic component such as a semiconductor element.

  In the case of using the flat heat diffusion component 10, 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 the heat of the first copper layer 2 is transferred from the flat portions 2a and 2b. Conducted 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 radiated to the outside via a heat radiation terminal (not shown) provided at the end of the first member 11 or the like, The air is released from the exposed surface of the layer 2 (for example, into the air) and diffuses. At the same time, the heat conducted in the first copper layer 2 in the Z direction is conducted into the stainless steel layer 3. The heat conducted to the stainless steel layer 3 is transferred to the second copper layer 4 adjacent to the stainless steel layer 3 in a direction in which the level of heat energy is low and heat conduction is easy, that is, the conduction direction is relatively small in the Z direction. Conduct preferentially. The heat conducted to the second copper layer 4 is conducted in the X, Y and Z directions inside the second copper layer 4. The heat conducted in the X direction and the Y direction inside the second copper layer 4 is radiated to the outside via a heat radiation terminal (not shown) provided at the end of the first member 11 or the like, or Emitted from the exposed surface of layer 4 into the air (eg, into the atmosphere) and diffuses.

  The heat diffusion component 10 in the form of a flat plate has an appropriate heat conduction property by the copper layer (the first copper layer 2 and the second copper layer 4) and an appropriate mechanical property by the stainless steel layer 3 that constitute the first member 11. Have. Accordingly, such a flat 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 a small device or device such as a mobile personal computer or a mobile phone. If necessary, the conductive member, the chassis, the case, or the frame may have the function of the conductive member. As a result, it is expected that the above-described devices and apparatuses will contribute to a reduction in thickness, size, and weight.

(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 and is shown as a second configuration example. The shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 3 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a second configuration example, the case-shaped heat diffusion component 20 illustrated in FIG. 3 includes a first member 21, a second member 22, and an internal space 24. That is, it has an internal space constituted by the first member and the second member. Each of the first member 21 and the second member 22 is a composite metal plate having a T of 500 μm or less, a Ts / Tc of 0.2 to 5 and a Kx / Kz of 4.4 to 6.8. 1 (first copper layer 2 / stainless steel layer 3 / second copper layer 4). The first member 21 has a bent portion 21a formed on one end side (right side in the X direction) and a bent portion 21b formed on the other end side (left side in the X direction). The second member 22 has a bent portion 22a formed on one end side (right side in the X direction), and a bent portion 22b formed on the other end side (left side in the X direction). The first member 21 and the second member 22 are joined with each other at the end faces 21c and 22c of the bent portions 21a and 22a so that the internal space 24 is hermetically sealed (preferably, decompressed and sealed). The end surfaces 21d and 22d of the bent portions 21b and 22b are abutted and joined.

  Here, the joining between the first member 21 and the second member 22 may be performed by using a joining material such as solder or silver brazing. From the viewpoint of improving the sealing reliability, a method utilizing thermal diffusion (pressure diffusion bonding) is preferable. The pressure diffusion bonding uses heat diffusion generated by heating (heat treatment) in a state in which a load is applied so that the surfaces to be bonded are pressed against each other, and the surfaces to be bonded (the end surface portion 21c and the end surface portion 22c). And a method of joining the end face 21d and the end face 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. In addition, it is necessary to maintain the temperature at 600 ° C. or more and 1000 ° C. or less.

  The internal space 24 of the housing-shaped heat diffusion component 20 is hermetically sealed (preferably reduced pressure sealing) by the first member 21 and the second member 22. The member for hermetic sealing of the internal space 24 is not limited to the first member 21 and the second member 22, and other members such as a heat radiation terminal (not shown) may be involved. The hermetically sealed (preferably reduced pressure sealed) internal space 24 is used as a heat flow path by sealing a working fluid (refrigerant) capable of transporting heat by evaporation and condensation therein. can do. As the working fluid (refrigerant), for example, water, an alternative chlorofluorocarbon, alcohol, or an organic compound such as acetone can be used. From the viewpoint of safety, low cost, and easy handling, pure water is preferably used. .

  The housing-like heat diffusion component 20 directly or indirectly applies the heat sources 5a and 5b 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. Heatable source joining regions 2A and 2B that can be joined can be provided. The portions where the heat source joining regions 2A and 2B are provided may be set as needed, and are not limited to the surface of the first member 21. Further, the number of heat sources 5a and 5b may be any one, or may be three or more, and may be, for example, an electronic component such as a semiconductor element.

  In the case of using the housing-like heat diffusion component 20, the heat generated by the heat sources 5a, 5b is conducted to the first member 21 in contact with the heat sources 5a, 5b, and the first copper layer 2 is transferred from the flat portions 2a, 2b. Conducted 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 conducted from the joints 23a and 23b to the second member 22, and a heat radiation terminal (not shown) is provided at an end of the first member 21 or the like. Is provided, it is emitted to the outside and diffused, and a part is released from the exposed surface of the first copper layer 2 into the air (for example, in the air) and diffused. At the same time, the heat conducted in the first copper layer 2 in the Z direction is conducted into the stainless steel layer 3. The heat conducted to the stainless steel layer 3 is transferred to the second copper layer 4 adjacent to the stainless steel layer 3 in a direction in which the level of heat energy is low and heat conduction is easy, that is, the conduction direction is relatively small in the Z direction. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed in the direction of the internal space 24 where the working fluid (refrigerant) having a low energy level and easily conducting heat exists inside the second copper layer 4, that is, in the Z direction. To conduct. 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 radiated at the end of the internal space 24 and the like. It is released to the outside via a terminal (not shown). In addition, the heat conducted from the first member 21 to the second member 22 is radiated to the outside and diffused through a path similar to the behavior of the first member 21.

  The heat diffusion component 20 in the form of a housing is formed of the first member 21 and the second member 22, and has an appropriate heat conduction property by the copper layers (the first copper layer 2 and the second copper layer 4) and the stainless steel layer 3. Has moderate mechanical properties. Thereby, the case-shaped heat diffusion component 20 can be reduced in thickness by reducing the thickness (length in the Z direction) of the case. Such a housing-like heat diffusion component 20 can be said to be a flat heat pipe having a high heat dissipation effect (heat 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 dissipating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, it can also have the function of a conductive member, a chassis, a case or a frame. As a result, it is expected that the above-described devices and apparatuses will contribute to a reduction in thickness, size, and weight.

(Modification of Second Configuration Example)
FIG. 4 is a cross-sectional configuration of a housing-like heat diffusion component 20A, which is one embodiment of the heat diffusion component according to the present invention, which is shown as a modification of the second configuration example. The shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 4 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a modification of the second configuration example, a housing-like heat diffusion component 20A shown in FIG. 4 includes a first member 21, a second member 22, and an internal space, like the heat diffusion component 20 described above. And a support portion 25. The support portion 25 is arranged in the internal space and is joined to the second copper layer 4 forming the first member 21 and the second copper layer 4 forming the second member 22. This increases the mechanical strength of the housing-like heat diffusion component 20A, so that the housing-like heat diffusion component 20A can be made thinner. Further, the internal space is divided into two internal spaces 24a and 24b by the support portion 25. By providing the support portion 25 with the communication path 25a, the two internal spaces 24a and 24b can be connected. In this case, the number of the communication paths 25a provided in the support portion 25 is not limited to one, and a plurality of communication paths can be provided as necessary. The first member 21 and the second member 22 that constitute 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 A description of a working fluid (refrigerant) or the like that is hermetically sealed (preferably, decompressed and sealed) in the internal spaces 24a and 24b is omitted here, and the description of the above-described heat diffusion component 20 is referred to.

  When the housing-like heat diffusion component 20A is used, the heat generated by the heat sources 5a and 5b is generated by the first member 21 in contact with the heat sources 5a and 5b, as in the case of the above-described housing heat diffusion component 20. Through the first copper layer 2, the stainless steel layer 3, and the second copper layer 4 from the plane portions 2a and 2b, and most of the heat energy levels of the internal spaces 24a and 25b from the exposed surface of the second copper layer 4. Is transmitted to the lower working fluid (refrigerant), is transported by the working fluid (refrigerant), and is discharged to the outside via 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 inner space 24a and the amount of heat conducted to the working fluid (refrigerant) in the inner space 24b are different, the working fluid in the inner spaces 24a and 25n is different. The working fluid (refrigerant) can move through the communication path 25a of the support 25 so that the level of thermal energy of the (refrigerant) is balanced. In addition, the heat conducted from the first member 21 to the second member 22 is radiated to the outside and diffused through a path similar to the behavior of the first member 21.

  The housing-like heat diffusion component 20 </ b> A includes a first member 21 and a second member 22, each having an appropriate heat conduction characteristic by a copper layer (the first copper layer 2 and the second copper layer 4) and a stainless steel layer 3. Has moderate mechanical properties. Further, the housing-like heat diffusion component 20A has a support portion 25 joined to the first member 21 and the second member 22. Thereby, the housing-shaped heat diffusion component 20A is reinforced, and the thickness (length in the Z direction) of the housing can be further reduced, so that the thickness can be further reduced. Such a housing-like heat diffusion component 20A is suitable for use as a housing of the above-described vapor chamber. Further, the housing-like heat diffusion component 20A can be mounted as a heat diffusion component such as a heat radiating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, it can have the function of a conductive member, a chassis, a case or a frame. As a result, it is expected that the above-described devices and apparatuses will contribute to further reduction in thickness, size, and weight.

(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, which is shown as a third configuration example. The shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 5 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a third configuration example, the case-shaped heat diffusion component 30 illustrated in FIG. 5 includes a first member 31, a second member 32, and an internal space. That is, it has an internal space constituted by the first member and the second member. The first metal member 31 and the second metal member 32 both 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 formed at one end (the right side in the X direction) and a bent portion 31b formed at the other end (the 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 formed such that the end surface 31c of the bent portion 31a of the first member 31 is flat on the second member 32 so that the internal space 34 is hermetically sealed (preferably, depressurized sealing). The end face 31d of the bent portion 31b of the first member 31 is joined to the flat portion 32b of the second member 32 while being abutted against the portion 32a.

  Here, the joining of the first member 31 and the second member 32 may be performed by using a joining material such as solder or silver braze. From the viewpoint of improving the sealing reliability, a method utilizing thermal diffusion (pressure diffusion bonding) is preferable. The pressure diffusion bonding uses heat diffusion generated by heating (heat treatment) in a state where a load is applied so that the surfaces to be bonded are pressed against each other, and the surfaces to be bonded (the end surface portion 31c and the flat surface portion 32a). And a method of joining the end face 31d and the flat face 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. In addition, it is necessary to maintain the temperature at 600 ° C. or more and 1000 ° C. or less.

  The internal space 34 of the housing-like heat diffusion component 30 is hermetically sealed (preferably reduced pressure sealing) by the first member 31 and the second member 32. The member for hermetic sealing of the internal space 34 is not limited to the first member 31 and the second member 32, and other members such as a heat radiation terminal (not shown) may be involved. The hermetically sealed (preferably reduced pressure sealed) internal space 34 is used as a heat flow path by sealing a working fluid (refrigerant) that enables heat transport by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, an alternative chlorofluorocarbon, alcohol, or an organic compound such as acetone can be used. From the viewpoint of safety, low cost, and easy handling, pure water is preferably used. .

  The housing-like heat diffusion component 30 directly or indirectly applies the heat sources 5a and 5b 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. Heatable source joining regions 2A and 2B that can be joined can be provided. The portions where the heat source joining regions 2A and 2B are provided may be set as needed, and are not limited to the surface of the first member 31. Further, the number of heat sources 5a and 5b may be any one, or may be three or more, and may be, for example, an electronic component such as a semiconductor element.

  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 the first copper layer 2 is transferred from the flat portions 2a and 2b. Conducted 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 conducted from the joints 33a and 33b to the second member 32, and a heat dissipation terminal (not shown) is provided at an end of the first member 31 or the like. Is provided, it is emitted to the outside and diffused, and a part is released from the exposed surface of the first copper layer 2 into the air (for example, in the air) and diffused. At the same time, the heat conducted in the first copper layer 2 in the Z direction is conducted into the stainless steel layer 3. The heat conducted to the stainless steel layer 3 is transferred to the second copper layer 4 adjacent to the stainless steel layer 3 in a direction in which the level of heat energy is low and heat conduction is easy, that is, the conduction direction is relatively small in the Z direction. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed in the direction of the internal space 34 where the working fluid (refrigerant) having a low energy level and easily conducting heat exists inside the second copper layer 4, that is, in the Z direction. To conduct. 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 radiated at the end of the internal space 34 and the like. It is emitted to the outside via a terminal (not shown). The heat conducted from the first member 31 to the second member 32 is radiated to the outside and diffused through a path similar to the behavior of the first member 31.

  The housing-like heat diffusion component 30 is composed of the first member 31 and the second member 32, and has an appropriate heat conduction characteristic by a copper layer (the first copper layer 2 and the second copper layer 4) and a stainless steel layer 3. Has moderate mechanical properties. Thus, the housing-shaped heat diffusion component 30 can be made thinner by reducing the thickness (length in the Z direction) of the housing. Such a housing-like heat diffusion component 30 can be said to be a flat heat pipe having a high heat dissipation effect (heat diffusion effect), and is suitable for use as the housing of the above-described vapor chamber. In addition, the heat diffusion component 30 in the form of a housing can be mounted as a heat diffusion component such as a heat radiation member or a heat transfer member to be mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, the conductive member, the chassis, the case, or the frame can also have the function. As a result, it is expected that the above-described devices and apparatuses will contribute to a reduction in thickness, size, and weight.

(Modification of 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, which is shown as a modification of the third configuration example. The shapes, dimensions, ratios, magnifications, and the like of the members shown in FIG. 6 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a modification of the third configuration example, a housing-like heat diffusion component 30A shown in FIG. 6 includes a first member 31, a second member 32, and an internal space, like the heat diffusion component 30 described above. And a support portion 35. The support portion 35 is arranged in the internal space, and is joined to the second copper layer 4 forming the first member 31 and the second copper layer 4 forming the second member 32. This increases the mechanical strength of the housing-like heat diffusion component 30A, so that the housing-like heat diffusion component 30A can be made thinner. Further, the internal space is divided into two internal spaces 34a and 34b by the support portion 35. By providing the support portion 35 with the communication path 35a, the two internal spaces 34a and 34b can be connected. In this case, the number of communication paths 35a provided in the support portion 35 is not limited to one, and a plurality of communication paths 35a can be provided as needed. The first member 31 and the second member 32 that constitute 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 A description of a working fluid (refrigerant) or the like that is hermetically sealed (preferably reduced-pressure sealed) in the two internal spaces 34a and 34b will be omitted here, and the description of the above-described heat diffusion component 30 will be referred to.

  When the housing-shaped heat diffusion component 30A is used, the heat generated by the heat sources 5a and 5b is generated by the first member 31 in contact with the heat sources 5a and 5b, as in the case of the housing-shaped heat diffusion component 30 described above. Through the first copper layer 2, the stainless steel layer 3, and the second copper layer 4 from the plane portions 2a and 2b, and most of the heat energy level of the internal spaces 34a and 35b from the exposed surface of the second copper layer 4 Is transmitted to the lower working fluid (refrigerant), is transported by the working fluid (refrigerant), and is discharged to the outside via 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 inner space 34a and the amount of heat conducted to the working fluid (refrigerant) in the inner space 34b are different, the working fluid in the inner spaces 34a and 35n is different. The working fluid (refrigerant) can move through the communication path 35a of the support portion 35 so that the level of the thermal energy of the (refrigerant) is balanced. The heat conducted from the first member 31 to the second member 32 is radiated to the outside and diffused through a path similar to the behavior of the first member 31.

  The housing-like heat diffusion component 30 </ b> A has an appropriate heat conduction characteristic by 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. Has moderate mechanical properties. Further, the housing-like heat diffusion component 30A has a support portion 35 joined to the first member 31 and the second member 32. Thereby, the case-shaped heat diffusion component 30A is reinforced, and the thickness (length in the Z direction) of the case can be further reduced, so that the thickness can be further reduced. Such a case-shaped heat diffusion component 30A is suitable for use as a case of the above-described vapor chamber. Further, the housing-like heat diffusion component 30A can be mounted as a heat diffusion component such as a heat dissipating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, the conductive member, the chassis, the case, or the frame can also have the function. As a result, it is expected that the above-described devices and apparatuses will contribute to further reduction in thickness, size, and weight.

(Fourth configuration example)
FIG. 7 is a cross-sectional configuration of a housing-like heat diffusion component 40, which is one embodiment of the heat diffusion component according to the present invention, and is shown as a fourth configuration example. The shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 7 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a fourth configuration example, the case-shaped heat diffusion component 40 illustrated in FIG. 7 includes a first member 41, a second member 42, and an internal space 44. That is, it has an internal space constituted by the first member and the second member. The first member 41 is formed of the composite metal plate 1 (first copper layer 2) having T of 500 μm or less, Ts / Tc of 0.2 or more and 5 or less, and 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 formed on one end side (right side in the X direction) and a bent portion 41b formed on the other end side (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. In addition, the copper plate part 42a which comprises the 2nd member 42 can also be comprised using the stainless steel plate comprised by 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 increases, and a working fluid (refrigerant) existing in the internal space 44 from the second member 42 side. Heat is easily transmitted to the working fluid, and the heat transfer efficiency of the working fluid (refrigerant) can be improved.

  The form of the copper plate part 42a and the porous copper part 42b constituting the second member 42 is a form in which a porous copper part 42b having a three-dimensionally porous form such as a sintered member is joined to the copper plate part 42a. Alternatively, an etching process or an anodic oxidation process may be performed on one surface of the copper plate to form a porous copper portion 42b having a planar porous shape in which irregularities are dispersed and arranged, and the copper plate The remaining portion may be a copper plate portion 42a.

  The first member 41 and the second member 42 are formed such that the end surface 42c of the second member 42 is a flat surface of the bent portion 41a of the first member 41 so that the internal space 44 is hermetically sealed (preferably, decompressed and sealed). While being abutted against the portion 41c, the end face 42d of the second member 42 is abutted against and joined to the flat portion 41d of the bent portion 41b of the first member 41. The joining between the first member 41 and the second member 42 may be performed by using a joining material such as solder or silver braze. However, the joining material prevents contamination of the inside of the housing, improves the joining strength, and seals the internal space 44. From the viewpoint of improving the reliability of the device, a method utilizing thermal diffusion (pressure diffusion bonding) is preferable. The pressure diffusion bonding uses heat diffusion generated by heating (heat treatment) in a state in which a load is applied so that the surfaces to be pressed are pressed against each other, and the surfaces to be bonded (the flat surface portion 41c and the end surface portion 42c). And a method of joining the flat portion 41d and the end face 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. In addition, it is necessary to maintain the temperature at 600 ° C. or more and 1000 ° C. or less.

  The internal space 44 of the housing-like heat diffusion component 40 is hermetically sealed (preferably reduced pressure sealing) by the first member 41 and the second member 42. In addition, a member related to the hermetic sealing of the internal space 44 is not limited to the first member 41 and the second member 42, and other members such as a heat radiation terminal (not shown) may be involved. The inner space 44 thus hermetically sealed (preferably depressurized) is used as a heat flow path by sealing a working fluid (refrigerant) capable of transporting heat by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, an alternative chlorofluorocarbon, alcohol, or an organic compound such as acetone can be used. From the viewpoint of safety, low cost, and easy handling, pure water is preferably used. .

  The housing-shaped heat diffusion component 40 directly or indirectly applies the heat sources 5a and 5b to the upper surface of the first member 41, that is, the plane portions 2a and 2b on the exposed surface of the first copper layer 2. Heatable source joining regions 2A and 2B that can be joined can be provided. The portions where the heat source joining regions 2A and 2B are provided may be set as needed, and are not limited to the surface of the first member 41. Further, the number of heat sources 5a and 5b may be any one, or may be three or more, and may be, for example, an electronic component such as a semiconductor element.

  In the case of using the housing-like heat diffusion component 40, the heat generated by the heat sources 5a, 5b is conducted to the first member 41 in contact with the heat sources 5a, 5b, and the first copper layer 2 is transferred from the flat portions 2a, 2b. Conducted 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 conducted from the joints 43a and 43b to the second member 42, and a heat radiation terminal (not shown) is provided at an end of the first member 41 or the like. Is provided, it is emitted to the outside and diffused, and a part is released from the exposed surface of the first copper layer 2 into the air (for example, in the air) and diffused. At the same time, the heat conducted in the first copper layer 2 in the Z direction is conducted into the stainless steel layer 3. The heat conducted to the stainless steel layer 3 is transferred to the second copper layer 4 adjacent to the stainless steel layer 3 in a direction in which the level of heat energy is low and heat conduction is easy, that is, the conduction direction is relatively small in the Z direction. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed in the direction of the internal space 44 where the working fluid (refrigerant) having a low energy level and easily conducting heat exists inside the second copper layer 4, that is, in the Z direction. To conduct. 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 is provided at the end of the internal space 44 and the like. It is released to the outside via a terminal (not shown). 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, and a part of the copper plate is used. The air is emitted from the exposed surface of the portion 42a (for example, into the air) and diffuses.

  The housing-like heat diffusion component 40 has an appropriate heat conduction characteristic by the copper layer (the first copper layer 2 and the second copper layer 4) and an appropriate mechanical characteristic by the stainless steel layer 3 which constitute the first member 41. Having. Thereby, the case-shaped heat diffusion component 40 can be made thinner by reducing the thickness (length in the Z direction) of the case. Such a housing-like heat diffusion component 40 can be said to be a flat heat pipe having a high heat radiation effect (heat diffusion effect), and is suitable for use as a 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 radiation member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, the conductive member, the chassis, the case, or the frame can also have the function. As a result, it is expected that the above-described devices and apparatuses will contribute to a reduction in thickness, size, and weight.

(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, which is shown as a modification of the fourth configuration example. The shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 8 are exaggerated and schematically illustrated for clarity, and hatched 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 a support portion 45. The support portion 45 is arranged in the internal space, and is joined to the second copper layer 4 forming the first member 41 and the copper plate portion 42a forming the second member 42. This increases the mechanical strength of the housing-like heat diffusion component 40A, so that the housing-like heat diffusion component 40A can be made thinner. Further, the internal space is divided into two internal spaces 44a and 44b by the support portion 45, but by providing the communication path 45a in the support portion 45, the two internal spaces 44a and 44b can be connected. In this case, the number of the communication paths 45a provided in the support portion 45 is not limited to one, and a plurality of communication paths can be provided as necessary. The first member 41 and the second member 42 that constitute 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 A description of a working fluid (refrigerant) or the like that is hermetically sealed (preferably, decompressed and sealed) in the two internal spaces 44a and 44b is omitted here, and the description of the above-described heat diffusion component 40 is referred to.

  When the case-shaped heat diffusion component 40A is used, the heat generated by the heat sources 5a and 5b is generated by the first member 41 that is in contact with the heat sources 5a and 5b, as in the case of the case-shaped heat diffusion component 40 described above. Through the first copper layer 2, the stainless steel layer 3, and the second copper layer 4 from the plane portions 2a and 2b, and most of the heat energy level of the internal spaces 44a and 45b from the exposed surface of the second copper layer 4. Is transmitted to the lower working fluid (refrigerant), is transported by the working fluid (refrigerant), and is discharged to the outside via 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 inner space 44a is different from the amount of heat conducted to the working fluid (refrigerant) in the inner space 44b, the working fluid in the inner spaces 44a and 45n is different. The working fluid (refrigerant) can move through the communication path 45a of the support portion 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, and a part of the copper plate is used. The air is emitted from the exposed surface of the portion 42a (for example, into the air) and diffuses.

  The housing-like heat diffusion component 40 </ b> A has a first member 41, a moderate heat conduction property of the copper layer (the first copper layer 2 and the second copper layer 4) and a moderate mechanical property of the stainless steel layer 3. Having. Further, the housing-like heat diffusion component 40A has a support portion 45 joined to the first member 41 and the second member 42. Thereby, the case-shaped heat diffusion component 40A is reinforced, and the thickness (length in the Z direction) of the case can be further reduced, so that the thickness can be further reduced. Such a case-shaped heat diffusion component 40A is suitable for use as a case of the above-described vapor chamber. In addition, the housing-like heat diffusion component 40A can be mounted as a heat diffusion component such as a heat radiating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, the conductive member, the chassis, the case, or the frame can also have the function. As a result, it is expected that the above-described devices and apparatuses will contribute to further reduction in thickness, size, and weight.

(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 and is shown as a fifth configuration example. Note that the shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 9 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a fifth configuration example, the case-shaped heat diffusion component 50 illustrated in FIG. 8 includes a first member 51, a second member 52, and an internal space 54. That is, it has an internal space constituted by the first member and the second member. The first member 51 is a composite metal plate 1 (the first copper layer 2) having T of 500 μm or less, Ts / Tc of 0.2 or more and 5 or less, and 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 formed on one end side (right side in the X direction) and a bent portion 51b formed on the other end side (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. In addition, the copper plate part 52a which comprises the 2nd member 52 can also be comprised using the stainless steel plate comprised by stainless steel. 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) existing in the internal space 54 from the second member 52 side. Heat is easily transmitted to the working fluid, and the heat transfer efficiency of the working fluid (refrigerant) can be improved.

  The form of the copper plate part 52a and the porous copper part 52b that constitute the second member 52 is a form in which a porous copper part 52b having a three-dimensionally porous form such as a sintered member is joined to the copper plate part 52a. Alternatively, an etching process or an anodic oxidation process may be performed on one surface of the copper plate to form a porous copper portion 52b having a planar porous shape in which irregularities are dispersed and arranged, and the copper plate The remaining portion may be a copper plate portion 52a.

  The first member 51 and the second member 52 are formed such that the end surface 51c of the bent portion 51a of the first member 51 is flat on the second member 52 so that the internal space 54 is hermetically sealed (preferably, decompressed and sealed). The end portion 51d of the bent portion 51b of the first member 51 is joined to the flat portion 52d of the second member 52, while being joined to the portion 52c. The joining between the first member 51 and the second member 52 may be performed by using a joining material such as solder or silver braze. From the viewpoint of improving the reliability of the device, a method utilizing thermal diffusion (pressure diffusion bonding) is preferable. The pressure diffusion bonding uses heat diffusion generated by heating (heat treatment) in a state in which a load is applied so that the surfaces to be bonded 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. In addition, it is necessary to maintain the temperature at 600 ° C. or more and 1000 ° C. or less.

  The internal space 54 of the housing-like heat diffusion component 50 is hermetically sealed (preferably reduced pressure sealing) by the first member 51 and the second member 52. In addition, the member related to the hermetic sealing of the internal space 54 is not limited to the first member 51 and the second member 52, and other members such as a heat radiation terminal (not shown) may be involved. The hermetically sealed (preferably reduced pressure sealed) internal space 54 is used as a heat flow path by sealing a working fluid (refrigerant) that enables heat transport by evaporation and condensation. can do. As the working fluid (refrigerant), for example, water, an alternative chlorofluorocarbon, alcohol, or an organic compound such as acetone can be used. From the viewpoint of safety, low cost, and easy handling, pure water is preferably used. .

  The housing-like heat diffusion component 50 directly or indirectly applies the heat sources 5a and 5b to the upper surface of the first member 51, that is, the plane portions 2a and 2b on the exposed surface of the first copper layer 2. Heatable source joining regions 2A and 2B that can be joined can be provided. The portions where the heat source joining regions 2A and 2B are provided may be set as needed, and are not limited to the surface of the first member 51. Further, the number of heat sources 5a and 5b may be any one, or may be three or more, and may be, for example, an electronic component such as a semiconductor element.

  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 is transferred from the flat portions 2a and 2b. Conducted 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 conducted from the joints 53a and 53b to the second member 52, and a heat dissipation terminal (not shown) is provided at an end of the first member 51 or the like. Is provided, it is emitted to the outside and diffused, and a part is released from the exposed surface of the first copper layer 2 into the air (for example, in the air) and diffused. At the same time, the heat conducted in the first copper layer 2 in the Z direction is conducted into the stainless steel layer 3. The heat conducted to the stainless steel layer 3 is transferred to the second copper layer 4 adjacent to the stainless steel layer 3 in a direction in which the level of heat energy is low and heat conduction is easy, that is, the conduction direction is relatively small in the Z direction. Conduct preferentially. The heat conducted to the second copper layer 4 is preferentially directed in the direction of the internal space 54 where the working fluid (coolant) having a low energy level and easily conducting heat exists inside the second copper layer 4, that is, in the Z direction. To conduct. 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 is provided at the end of the internal space 54 and the like. It is released to the outside via a terminal (not shown). Note that 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. The air is released from the exposed surface of the portion 52a (for example, into the air) and diffuses.

  The housing-like heat diffusion component 50 has a moderate heat conduction property by the copper layer (the first copper layer 2 and the second copper layer 4) and a moderate mechanical property by the stainless steel layer 3 that constitute the first member 51. Having. Thus, the housing-shaped heat diffusion component 50 can be made thinner by reducing the thickness (length in the Z direction) of the housing. Such a housing-like heat diffusion component 50 can be said to be a flat heat pipe having a high heat dissipation effect (heat diffusion effect), and is suitable for use as a housing of the above-described vapor chamber. In addition, the housing-like heat diffusion component 50 can be mounted, for example, as a heat diffusion component such as a heat radiating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, it can also have the function of a conductive member, a chassis, a case or a frame. As a result, it is expected that the above-described devices and apparatuses will contribute to a reduction in thickness, size, and weight.

(Modification of 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, which is shown as a modification of the fifth configuration example. The shapes, dimensions, ratios, magnifications, and the like of each member shown in FIG. 10 are exaggerated and schematically illustrated for clarity, and hatched lines representing cross sections are omitted for simplification.

  As a modification of the fifth configuration example, a housing-like heat diffusion component 50A shown in FIG. And a support portion 55. The support portion 55 is disposed in the internal space, and is joined to the second copper layer 4 forming the first member 51 and the copper plate portion 52a forming the second member 52. This increases the mechanical strength of the housing-like heat diffusion component 50A, so that the housing-like heat diffusion component 50A can be made thinner. Further, 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 a communication path 55a in the support portion 55. In this case, the number of communication paths 55a provided in the support portion 55 is not limited to one, and a plurality of communication paths may be provided as necessary. The first member 51 and the second member 52 that constitute 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 A description of a working fluid (refrigerant) or the like that is hermetically sealed (preferably depressurized sealed) in the two internal spaces 54a and 54b is omitted here, and the description of the above-described heat diffusion component 50 is referred to.

  When the housing-like heat diffusion component 50A is used, the heat generated by the heat sources 5a and 5b is generated by the first member 51 in contact with the heat sources 5a and 5b, as in the case of the above-described housing heat diffusion component 50. Through the first copper layer 2, the stainless steel layer 3 and the second copper layer 4 from the flat portions 2a and 2b, most of which are from the exposed surface of the second copper layer 4 to the heat energy levels of the internal spaces 54a and 55b. Is transmitted to the lower working fluid (refrigerant), is transported by the working fluid (refrigerant), and is discharged to the outside via a heat radiation terminal (not shown) provided at the end of the internal space 54a, 54b. At this time, even if the amount of heat conducted to the working fluid (refrigerant) in the inner space 54a is different from the amount of heat conducted to the working fluid (refrigerant) in the inner space 54b, the working fluid of the inner spaces 54a and 55n is different. The working fluid (refrigerant) can move through the communication path 55a of the support portion 55 so that the level of the thermal energy of the (refrigerant) is balanced. Note that 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 via the porous copper portion 52b, and is radiated to the outside and diffused. Is released from the exposed surface of the copper plate portion 52a into the air (for example, in the air) and diffuses.

  The housing-like heat diffusion component 50 </ b> A has a suitable heat conduction property by the copper layer (the first copper layer 2 and the second copper layer 4) and a suitable mechanical property by the stainless steel layer 3 that constitute the first member 51. Having. Further, the housing-like heat diffusion component 50A has a support portion 55 joined to the first member 51 and the second member 52. Thereby, the housing-like heat diffusion component 50A is reinforced, and the thickness (length in the Z direction) of the housing can be further reduced, so that the thickness can be further reduced. Such a housing-like heat diffusion component 50A is suitable for use as a housing of the above-described vapor chamber. Further, the housing-like heat diffusion component 50A can be mounted as a heat diffusion component such as a heat radiating member or a heat transfer member mounted on a small device or device such as a mobile personal computer or a mobile phone. If necessary, it can have the function of a conductive member, a chassis, a case or a frame. As a result, it is expected that the above-described devices and apparatuses will contribute to further reduction in thickness, size, and weight.

  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 manufactured and evaluated. Specifically, as shown in Table 1, the thickness ratio (Ts / Tc) of the composite metal plate 1 was changed to change the mechanical characteristics of the composite metal plate 1 and the heat conduction characteristics (Kx, Kz) in the X and Z directions. ) And the anisotropy (AIS) of the heat conduction characteristics were confirmed. The thickness ratio was determined using an optical microscope photograph of the cross section, and the mechanical strength (tensile strength, 0.2% proof stress, elongation) was measured according to JIS-Z2241: 2011, and the hardness was measured according to JIS- It was determined based on Z2245: 2016. The thermal conductivity was determined by a method described later. In addition, the test specimens used for the various evaluations were cut out from the composite metal sheet 1 produced by using the materials shown in Table 1 by the above-described method for producing a clad sheet material, to a predetermined size suitable for various evaluations. The results are shown in Tables 1 and 2, FIGS. 11, 12 and 13. In Tables 1 and 2, a single stainless steel plate (stainless steel layer) and a single copper plate (copper layer) are similarly described for comparison with the composite metal plate 1.

(Mechanical properties of composite metal plate)
As 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, when Ts / Tc is 0.5 (Nos. 6, 7, and 11), the tensile strength is from 489 MPa to 578 MPa, and when Ts / Tc is 1.5 (No. 1 to No. 1). 5) is from 558 MPa to 1171 MPa, when Ts / Tc is 2.0 (No. 8, 9, 12), it is from 665 MPa to 856 MPa, and when Ts / Tc is 3.0 (No. 10), it is 758 MPa. Met. As a result, the tensile strength of the composite metal plate 1 can be increased by increasing Ts / Tc from, for example, 0.5 to 1.5 or 2.0. 3 in a relatively wide range by adjusting the composition (material) of stainless steel, the finish rolling ratio for obtaining the final thickness (product thickness) of the composite metal plate 1, the presence or absence of heat treatment, and the conditions of heat treatment. It turned out to be selectable.

  Further, as shown in Table 2, the proof stress (0.2% proof stress) of the composite metal plate 1 is from 453 MPa to 551 MPa when Ts / Tc is 0.5 (Nos. 6, 7, and 11), and Ts / Tc When Tc is 1.5 (No. 5), it is 222 MPa, and when Ts / Tc is 2.0 (Nos. 8, 9, 12), it is 570 MPa to 675 MPa, and when Ts / Tc is 3.0. In the case (No. 10), it was 634 MPa. For reference, the 0.01% proof stress when the 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 in consideration of Ts / Tc to obtain 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 has been found that a relatively wide range can be selected by adjusting the rolling ratio, 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 (No. 6, 7, 11), and Ts / Tc Is 1.5% (Nos. 1 to 5) from 0.8% to 1.8%, and Ts / Tc is 2.0 (Nos. 8, 9, 12) from 24.6% to 34%. 0.7% and 39.5% when Ts / Tc was 3.0 (No. 10). As a result, taking into account Ts / Tc, the elongation of the composite metal plate 1 is obtained by obtaining 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 has been found that a relatively wide range can be selected by adjusting the rolling ratio, 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 from 301 HV to 353 HV when Ts / Tc is 0.5 (No. 6, 7, 11), and Ts / Tc is 2 In the case of 0.0 (Nos. 8, 9, 12), it was 281 HV to 381 HV, and when Ts / Tc was 3.0 (No. 10), it was 274 HV. As a result, in consideration of Ts / Tc, the hardness of the stainless steel of the composite metal plate 1 is determined by considering the composition (material) of the stainless steel constituting the stainless steel layer 3 and the final thickness of the composite metal plate 1 (product thickness). ) Can be selected in a relatively wide range by adjusting the finish rolling ratio, 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 from 88 HV to 103 HV when Ts / Tc is 0.5 (Nos. 6, 7, 11), and Ts / Tc is 2 In the case of 0.0 (No. 8, 9, 12), it was 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 adjusting the finish rolling ratio to obtain the final thickness (product thickness) of the composite metal plate 1 in consideration of Ts / Tc. It turned out that the range was selectable.

  Next, the thermal conductivity Kx of the composite metal plate 1 in the X direction (plane direction, rolling direction) was evaluated. Note that the thermal conductivity Kx in the X direction of the composite metal plate 1 shown in Table 2 and FIG. 11 is the thermal conductivity Ks (SUS631, SUS304) of the stainless steel constituting the stainless steel layer 3, the first copper layer 2 and the second Based on the thermal conductivity Kc of copper (C1020) constituting 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. I asked. Based on the thermal conductivity Kx thus determined, the relationship between Ts / Tc of the composite metal plate 1 and the thermal conductivity Kx in the X direction was arranged in a diagram (graph) shown in FIG.

  As shown in FIG. 11, the thermal conductivity Kx in the X direction of the composite metal plate 1 is 340 W / (m · K) or less when Ts / Tc of the composite metal plate 1 is in the range of 0.2 or more and 5 or less. It was found that Ts / Tc had a tendency to become smaller as it became larger (see a mark Δ and a mark ● in FIG. 11). As for the thermal conductivity Kx in the X direction, Ts / Tc increases when Ts / Tc is in the range of 0.2 or more and 4 or less (especially 0.2 or more and 3 or less, particularly 0.2 or more and 2 or less). It has been found that the degree of the decrease is large. For example, for a variation of Ts / Tc between 0.2 and 4 (3.8), the thermal conductivity Kx in the X direction is from about 340 W / (m · K) to about 120 to 100 W / (m · K). 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 change in Ts / Tc between 0.2 and 3 (2.8), the thermal conductivity Kx in the X direction is about 340 W / (m · K) to about 120 W / (m · K). (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 about 340 W / (m · K) to about 150 W / (m · K). (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 is represented by an approximate expression (exponential approximation) indicated by a broken line in FIG. (Logarithmic approximation), the relationship between Ts / Tc of composite metal plate 1 and thermal conductivity Kx in the X direction can be found appropriately and easily.

  The thermal conductivity Kz of the composite metal plate 1 in the Z direction (thickness direction, plate thickness direction) was evaluated. Here, in a metal material (metal layer) having the same configuration, the thermal conductivity in the Z direction of the metal layer is represented by the reciprocal (1 / K) of the thermal conductivity in the X direction (K). it can. Specifically, the thermal conductivity Kz in the Z direction of the composite metal plate 1 shown in Table 2 and FIG. 12 is the thermal conductivity Ks of the stainless steel constituting the stainless steel layer 3 (SUS631, SUS304), the first copper layer 2 Kz = Ts / Ks + Tc, 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). / Kc. Based on the thermal conductivity Kz thus obtained, the relationship between Ts / Tc of the composite metal plate 1 and the thermal conductivity Kz in the Z direction is arranged in a diagram (graph) shown in FIG.

  As shown in FIG. 12, the thermal conductivity Kz of the composite metal plate 1 in the Z direction is 20 W / (m · K) or more when Ts / Tc of the composite metal plate 1 is in the range of 0.2 or more and 5 or less. It was found that Ts / Tc had a tendency to become smaller as it became larger (see a mark Δ and a mark ● in FIG. 11). As for the thermal conductivity Kz in the Z direction, Ts / Tc increases when Ts / Tc is in the range of 0.2 or more and 4 or less (especially 0.2 or more and 3 or less, particularly 0.2 or more and 2 or less). It has been found that the degree of decrease with the increase has a tendency. For example, for a change in Ts / Tc between 0.2 and 4 (3.8), the thermal conductivity Kz in the Z direction is about 50 W / (m · K) to about 25 to 20 W / (m · K). 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 change in Ts / Tc between 0.2 and 3 (2.8), the thermal conductivity Kz in the Z direction is about 50 W / (m · K) to about 20 W / (m · K). (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 / (m · K) to about 25 W / (m · K). (The amount of change is about 25 W / (m · K)), and the change gradient is about 14 (25 / 1.8). From this viewpoint, it was found that the change gradient of the thermal conductivity Kz in the Z direction was about 1/6 times that of the thermal conductivity Kx in the X direction.

  The change tendency of the thermal conductivity Kz in the Z direction with respect to Ts / Tc of the composite metal plate 1 is represented by an approximate expression (exponential approximation) indicated by a broken line in FIG. Since logarithmic approximation) was able to be expressed with high reliability, 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.

  Further, using the thermal conductivity Kx and Kz of the composite metal plate 1 in the X and Z directions, 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 (AIS) of the thermal conductivity characteristic of No. 1 was evaluated. The relationship between Ts / Tc of the composite metal plate 1 and AIS indicating the anisotropy of the heat conduction characteristics was arranged in a diagram (graph) shown in FIG.

  As shown in FIG. 13, the anisotropy (AIS) of the heat conduction characteristic of the composite metal plate 1 is determined by AIS, that is, Kx / Kz, when Ts / Tc of the composite metal plate 1 is in the range of 0.2 or more and 5 or less. To find that 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 with increasing. Was completed. The tendency of change in the anisotropy (AIS) of the heat conduction characteristic with respect to Ts / Tc of the composite metal plate 1 can be reliably expressed by the approximate expression (linear approximation) indicated by the dotted line in FIG. The slope could be found to be around -0.49. Thus, the anisotropy (AIS) of the heat conduction characteristic of the composite metal plate 1 is such that the thickness (Ts) of the stainless steel layer 3 is large when Ts / Tc of the composite metal plate 1 is in the range of 0.2 or more and 5 or less. In other words, it was found that the anisotropy was weakened when the thickness (Tc) of the copper layer was reduced. This is because Ts / Tc of the composite metal plate 1 is increased to weaken the anisotropy of the heat conduction characteristic (reduce the AIS), thereby relatively weakening the heat diffusion in the composite metal plate 1X direction, This means that an operation for increasing the thermal diffusivity in the Z direction is possible. Alternatively, by reducing Ts / Tc of the composite metal plate 1 to increase the anisotropy of the heat conduction characteristics (increase AIS), the heat diffusion in the X direction of the composite metal plate 1 is relatively increased. , Z means that the operation of weakening the thermal diffusivity is possible.

  Utilizing the anisotropy (AIS) of the heat conduction characteristic of the composite metal plate 1, for example, a heat dissipating portion that radiates the heat released from the heat source to the outside is formed of a heat diffusion component X using the composite metal plate 1. In the case where it is arranged at the side end in the direction, the Ts / Tc of the composite metal plate 1 used for the heat diffusion component is operated to be small (AIS is large), so that the heat in the X direction is increased. It is preferable to configure the composite metal plate 1 with enhanced diffusivity. Further, for example, in the case where a heat radiating portion that radiates heat released from the heat source to the outside is disposed at a side end in the Z direction of the heat diffusion component using the composite metal plate 1, the heat diffusion component is It is preferable to configure the composite metal plate 1 in which the heat diffusion in the X direction is enhanced by operating the composite metal plate 1 to be used so that Ts / Tc is increased (AIS is reduced).

  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, 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 and Z directions to the Ts / Tc of the composite metal plate 1 (Kx / Kz), that is, the anisotropy (AIS) in the thermal conductivity characteristics. The relationship and the change gradient in each relationship could be clarified. As a result, the composite metal plate having anisotropy (AIS) of the heat conduction characteristic suitable for the application in consideration of the relationship between the mechanical properties and the thermal conductivity Kx and Kz with respect to Ts / Tc of the composite metal plate 1 is considered. 1 can be found appropriately and easily.

  As a result, in various heat diffusion applications, necessary characteristics (eg, mechanical characteristics) other than heat conduction characteristics are generally different depending on the application, but the first copper layer, the stainless steel layer, and the second copper Of the composite metal plate for heat diffusion according to the present invention and the heat diffusion component using the composite metal plate, the thickness ratio of the stainless steel layer to the copper layer of the composite metal plate for heat diffusion (Ts / Tc) and the thermal conductivity ratio (Kx / Kz) of the composite metal plate for thermal diffusion in the X and Z directions (Kx / Kz), that is, the anisotropy of thermal conductivity (AIS), and various types of thermal diffusion are considered. It is now possible to appropriately and easily find a configuration suitable for the application.

  The present invention relates to a composite metal plate in which a stainless steel layer and a copper layer are alternately joined and has a total thickness of 500 μm or less, for example, a composite metal plate for use in a conductive member, a heat radiation member, a chassis, a case, a frame, and the like. The present invention has industrial applicability in that a plate can be appropriately and easily found according to the required characteristics of its use, and a composite metal plate suitable for various uses can be easily provided.

1. 1. Composite metal plate First copper layer, 2a. Plane part, 2b. Plane part, 2A. Heat source joining region, 2B. 2. Heat source bonding area Stainless steel layer 4. Second copper layer 5a. Heat source, 5b. Heat source X: Plane direction (rolling direction, longitudinal direction)
Y: Plane direction (rolling width direction, width direction)
Z: Thickness direction (plate thickness direction)
<Figure 2>
10. Heat diffusion component 11. First member <FIGS. 3 and 4>
20. Thermal diffusion components, 20A. Heat diffusion component 21. First member, 21a. Bent portion, 21b. Bent portion, 21c. End face, 21d. End face 22. The second member, 22a. Bend, 22b. Bent portion, 22c. End face, 22d. End faces 23a. Joint, 23b. Joint 24. Internal space (heat flow path), 24a. Internal space (heat flow path), 24b. Internal space (heat path)
25. Support, 25a. Connection <Figs. 5 and 6>
30. Parts for heat diffusion, 30A. Heat diffusion component 31. The first member, 31a. Bent portion, 31b. Bent portion, 31c. End face, 31d. End face 32. A second member, 32a. Flat part, 32b. The plane portions 33a. Joint, 33b. Joint 34. Internal space (thermal flow path), 34a. Internal space (heat flow path), 34b. Internal space (heat path)
35. Support, 35a. Connection <Figs. 7 and 8>
40. Parts for heat diffusion, 40A. Components for heat diffusion 41. First member, 41a. Bent portion, 41b. Bent portion, 41c. Flat part, 41d. Plane part 42. The second member, 42a. Copper plate part, 42b. Porous copper part, 42c. End face, 42d. End face 43a. Joint, 43b. Joint 44. Internal space (thermal flow path), 44a. Internal space (heat flow path), 44b. Internal space (heat path)
45. Support, 45a. Connection <Figs. 9 and 10>
50. Parts for heat diffusion, 50A. Parts for heat diffusion 51. The first member, 51a. Bent portion, 51b. Bent portion, 51c. End face, 51d. End face 52. The second member, 52a. Copper plate part, 52b. Porous copper part, 52c. Flat part, 52d. The plane portions 53a. Joint, 53b. Joint 54. Internal space (heat flow path), 54a. Internal space (heat flow path), 54b. Internal space (heat path)
55. Support, 55a. Connection

Claims (11)

A composite metal plate having a total thickness of 500 μm or less,
The first copper layer, the stainless steel layer, and the 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. Not less than 5 and
Assuming that the thermal conductivity in the plane direction of the composite metal plate is Kx and the thermal conductivity in the thickness direction of the composite metal plate is Kz, the ratio of the thermal conductivity determined by Kx / Kz is 4.4 or more. 8 or less, a composite metal plate for heat diffusion.   2. The composite metal plate for heat diffusion according to claim 1, wherein the Kx is 340 W / (m · K) or less, and the Kz is 20 W / (m · K) or more.   The first copper layer and the second copper layer are each made of pure copper having 99% by mass or more of Cu or a copper alloy having a higher thermal conductivity than the stainless steel forming the stainless steel layer. The composite metal plate for heat diffusion according to claim 1.   The stainless steel layer is composed of 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. The composite metal plate for heat diffusion according to any one of claims 1 to 3, wherein the composite metal plate is made of steel. A flat heat diffusion component using a heat diffusion composite metal plate having the first copper layer, the stainless steel layer, and the second copper layer according to any one of claims 1 to 4,
A first member made of the composite metal plate for heat diffusion,
A heat diffusion component, comprising: a heat source joining region to which a heat source can be directly or indirectly joined to a flat portion of the first member, the first copper layer or the second copper layer. A housing-like heat diffusion component using the heat diffusion composite metal plate having the first copper layer, the stainless steel layer, and the second copper layer according to any one of claims 1 to 4,
A first member configured by the composite metal plate for heat diffusion, a second member configured by the composite metal plate for thermal diffusion, and an internal space;
A bent portion at one end of the first member and a bent portion at one end of the second member are joined, and a bent portion at the other end of the first member and a bent portion at the other end of the second member. A heat diffusion component in which the internal space is hermetically sealed by joining the first and second parts. A housing-like heat diffusion component using the heat diffusion composite metal plate having the first copper layer, the stainless steel layer, and the second copper layer according to any one of claims 1 to 4,
A first member configured by the composite metal plate for heat diffusion, a second member configured by the composite metal plate for thermal diffusion, and an internal space;
A bent portion at one end of the first member is joined to a flat portion at one end of the second member, and a bent portion at the other end of the first member and a flat surface at the other end of the second member. A heat diffusion component in which the internal space is hermetically sealed by joining the first and second parts. A housing-like heat diffusion component using the heat diffusion composite metal plate having the first copper layer, the stainless steel layer, and the second copper layer according to any one of claims 1 to 4,
A first member configured by the composite metal plate for heat diffusion, a second member configured by including a copper plate portion, and an internal space,
A bent portion at one end of the first member is joined to an end surface at one end of the second member, and a bent portion at the other end of the first member and an end surface at the other end of the second member. A heat diffusion component in which the internal space is hermetically sealed by joining the first and second parts.   The heat diffusion component according to claim 8, further comprising a porous copper layer adjacent to the copper plate portion on the inner space side of the second member. A housing-like heat diffusion component using the heat diffusion composite metal plate having the first copper layer, the stainless steel layer, and the second copper layer according to any one of claims 1 to 4,
A first member configured by the composite metal plate for heat diffusion, a second member configured by including a copper plate portion, and an internal space,
A bent portion at one end of the first member is joined to a flat portion at one end of the second member, and a bent portion at the other end of the first member and a flat surface at the other end of the second member. A heat diffusion component in which the internal space is hermetically sealed by joining the first and second parts.   The heat diffusion component according to claim 10, further comprising a porous copper layer adjacent to the copper plate portion on the inner space side of the second member.