JP4243654B2 - Liquid cooling plate for electronic device parts, method for manufacturing liquid cooling plate - Google Patents

Description

  The present invention is, for example, a liquid cooling plate for electronic device parts suitable for application to an electronic device that is required to be reduced in size and weight, such as a personal computer, particularly a portable personal computer, a method for manufacturing the liquid cooling plate, and The present invention relates to an electronic device in which the liquid cooling plate is incorporated.

  As means for cooling electronic components such as a CPU (Central Processing Unit) in an electronic device such as a personal computer, a device that is forcibly cooled by a cooling fan has been widely used. However, since it is difficult to reduce the size of the cooling fan, for example, when applied to an electronic device that is required to be smaller and lighter, such as a portable personal computer, the mounting density of electronic components in the electronic device is increased. There are inconveniences such as an obstacle to the above, and it also affects the downsizing and weight reduction of the electronic device itself. In addition, the cooling fan is also dissatisfied with generating noise, and in particular, cooling with high cooling efficiency due to recent high-speed electronic circuits and improved performance of CPUs (for example, CPUs driven at a high frequency of several gigahertz). When the fan is adopted, the problem of noise becomes even greater.

In response to the problem of the cooling fan as described above, in recent years, the adoption of a liquid cooling type cooling device is becoming widespread. This liquid cooling type cooling device is sometimes referred to as a metal plate-like liquid cooling heat sink (“cold plate”) with a built-in liquid passage for circulating a cooling medium such as water (liquid; hereinafter referred to as cooling liquid). In the following, a cold plate) may be brought into contact with an electronic component such as a CPU, and the heat generated from the electronic component by the cooling liquid that has passed through the liquid passage is transferred to the outside of the device (or the housing of the device). The electronic component is cooled by being conveyed to a heat radiation side heat sink provided in the vicinity of the housing (see, for example, Patent Documents 1 to 3).
This liquid cooling type cooling device is easy to downsize compared to a cooling fan, hinders the increase in the mounting density of electronic components in electronic devices, and makes electronic devices themselves smaller and lighter. Inconvenience that affects the In addition, the problem of noise can be solved.
JP 2003-050645 A JP 2002-261480 A JP-A-7-142886

  By the way, in the case of the above-described liquid cooling type cooling device, a cold plate is widely adopted in which a metal tube forming a liquid passage is sandwiched between a pair of metal plates and formed into a plate shape as a whole. By bringing the metal plate into contact with the electronic component, the heat of the electronic component is transmitted to the cooling liquid in the metal tube via the metal plate and the metal tube to be cooled (see Patent Document 1 described above). (Refer FIG. 2, FIG. 1 of patent document 2, FIG. 5 of patent document 3, etc.). That is, it is a structure in which the heat of the electronic component is transmitted to the cooling liquid in the liquid passage through two members (a metal plate and a metal tube), which is unsatisfactory that it hinders improvement in cooling efficiency. there were. In addition, when the above-described liquid cooling type cooling device is applied to an electronic device that requires a high mounting density of an electronic component, such as a portable personal computer, the cold plate is reduced in size (especially the thickness dimension). However, as described above, there is a limit to downsizing (especially the reduction in thickness) of a cold plate having a structure in which a metal tube is sandwiched between a pair of metal plates. There has been a case in which the reduction of the size such as the thickness dimension of the film is affected.

  The present invention has been made in view of the above problems, and can improve the cooling efficiency of electronic components, and can easily realize downsizing (especially reduction in thickness dimension) of electronic device components, It aims at providing the manufacturing method and a liquid cooling device.

In order to solve the above problems, the present invention provides the following configuration.
In the present invention, there is provided a metal plate laminate in which a plurality of aluminum plates are brazed without flux in the atmosphere, and the metal plate laminate includes at least one surface of the aluminum plate in the metal plate laminate. A cooling liquid flow passage meanderingly extending in the plate surface direction of the aluminum plate material is formed by a recessed groove or a through hole penetrating in the plate thickness direction, and one end and the other end of the cooling liquid flow passage Are respectively connected to an opening for cooling liquid introduction and an opening for cooling liquid discharge, which are openings on the outer surface side of the aluminum plate material of the through holes formed in the aluminum plate material on one side of the metal plate laminate , The aluminum plate material on one side of the metal plate laminate has a cooling liquid inlet and a cooling liquid outlet, which are tubes made of aluminum or a base alloy thereof, at the joints having a square cross section. The holes formed are aligned with the through-holes of the aluminum plate material, and the joints are joined by brazing by non-flux lap brazing in the atmosphere. The flux lap brazing is performed by previously inserting an aluminum thin laminated plate material at the overlapping interface of a plurality of aluminum plate members constituting the metal plate laminate, and a cooling liquid inlet and a cooling liquid discharge port. Flux brazing in the air to the aluminum plate is performed by inserting an aluminum thin laminated plate in advance between the joint of the cooling liquid inlet and the cooling liquid outlet and the aluminum plate on one side of the metal plate laminate. Aluminum brazing performed, wherein the aluminum thin laminated plate has a melting point of 600 ° C. or lower And a core material made of an aluminum alloy having a higher melting point than the core material, and Mg is contained in one or more of the core material and the skin material in an amount of 0.1 to 6% (mass%, The same shall apply hereinafter) or a three-layer structure in which Bi is added in an amount of 0.01 to 1%, or an intermediate composed of a brazing material having a melting point of 600 ° C. or lower between the core material and the skin material on both sides thereof. The core material and the both skin materials are made of an aluminum alloy having a melting point higher than that of the intermediate material, and more than 0.1 Mg is added to any one or more of the core material, the skin material, and the intermediate material. It is a five-layer structure with 6% or 0.01 to 1% of Bi added, and in the atmosphere with the cooling liquid inlet, the cooling liquid outlet, and the entire laminated plate in pressure contact. More than the liquidus temperature of the brazing material and the solidus temperature of each member other than the brazing material Providing a liquid cold plate of electronic components which are heated to a temperature range, characterized in der Rukoto made brazed lap collectively not exceeding the minimum value of the.
Further, in the present invention, a plurality of aluminum plates made of aluminum or a base alloy thereof are joined by airless fluxless brazing, so that the grooves formed in one of the aluminum plates or the aluminum plate While assembling a metal plate laminate incorporating a cooling liquid flow path formed by through holes penetrating in the plate thickness direction, a pipe made of aluminum or a base alloy thereof is applied to the aluminum plate material on one side of the metal plate laminate. A cooling liquid introduction port and a cooling liquid discharge port are formed in the through hole formed in the aluminum plate material on one side of the metal plate laminate. Match the opening for cooling liquid introduction and the opening for cooling liquid discharge, which are openings on the outer surface side, respectively, and connect the joints to the atmosphere. And joined by brazing by fluxless superposed brazing, a method for producing a liquid cold plate assembly of the liquid cooling plate, atmosphere fluxless superposed brazing of the aluminum sheet material to each other, constituting the metal plate stack Aluminum laminating by inserting an aluminum thin laminated plate in advance at the overlapping interface of a plurality of aluminum plates, and flux-free brazing in the air against the aluminum plates at the cooling liquid inlet and the cooling liquid outlet are the cooling liquid. The aluminum thin brazing is performed by inserting an aluminum thin laminated plate in advance between the introduction port and the joint of the cooling liquid outlet and the aluminum plate on one side of the metal plate laminate. A core material made of a brazing material having a melting point of 600 ° C. or lower, and aluminum having a melting point higher than that of the core material And at least one of the core material and the skin material is 0.1 to 6% Mg (mass%, the same shall apply hereinafter), or 0.01 to 1% Bi. An intermediate material composed of a brazing material having a melting point of 600 ° C. or lower is provided between the added three-layer structure or between the core material and the skin material on both sides thereof, and the core material and both skin materials Is made of an aluminum alloy having a melting point higher than that of the intermediate material, and 0.1 to 6% of Mg or 0.01 to 1% of Bi is further added to at least one of the core material, the skin material, and the intermediate material. And a brazing filler metal having a temperature higher than the liquidus temperature of the brazing filler metal in the atmosphere in a state where the cooling liquid inlet, the cooling liquid outlet, and the entire laminated plate are in pressure contact with each other. Heat to a temperature range that does not exceed the minimum value of the solidus temperature of each member other than Overlapping Te to provide a manufacturing method of liquid cooling plates, characterized in Rukoto to be brazed.
In the present specification, “brazing” is a general term indicating high-temperature brazing without flux in the atmosphere.

In the liquid cooling plate (hereinafter sometimes abbreviated as “liquid cooling plate”) of the electronic device component according to the present invention, as an aluminum plate material (hereinafter also referred to as a flow path processing plate) for forming a cooling liquid flow path, When adopting a groove having a groove on one side (hereinafter also referred to as a metal plate with a groove), a metal plate (metal) attached to the surface of the metal plate with the groove is formed. One of the metal plates constituting the plate laminate (hereinafter also referred to as a sealing metal plate) and a cooling liquid flow path is secured by the concave groove between the concave grooved metal plate. When a metal plate with a through hole penetrating in the plate thickness direction (hereinafter also referred to as a metal plate with a through hole) is adopted as the flow path processing plate, it is attached to both surfaces of the metal plate with the through hole. A cooling liquid flow path is secured by the through hole between the metal plate (one of the metal plates constituting the metal plate laminate; hereinafter also referred to as a metal plate for sealing) and the metal plate with the through hole. .
The metal plate for sealing is not limited to a flat plate. For example, a metal plate with a groove that is similar to a metal plate with a groove is formed to increase the cross-sectional area of the cooling liquid flow passage. Is possible.
The above-mentioned “concave groove” is a groove groove formed in a shape obtained by removing a part of a metal plate (flow-path processed plate). For example, the metal plate is formed by pressing or the like. It does not include those formed by bending (those having a trough in the bending process as a concave groove). Moreover, the through-hole of the metal plate with a through-hole refers here to the long hole meanderingly extended in the plate | board surface direction of the metal plate (flow-path processing board). As a method of forming the concave groove or the through hole, it may be formed at the time of forming the metal plate itself in addition to processing such as cutting of the metal plate.

The structure of the cooling liquid introduction opening and the cooling liquid discharge opening is formed, for example, by fitting a square tube or a round tube to the opening of the cooling liquid flow passage that opens on the side surface of the metal plate laminate. In addition to the well-known joint structure that is fixedly configured, a metal plate that forms a laminate by sandwiching a tubular body having a square cross section aligned with the opening of the cooling liquid flow passage between the metal plates that constitute the metal plate laminate. Do not use what is brazed together.
The present inventors tried various connection structures and recognized that the joint having the structure shown in FIGS. 1 to 3 was easy to manufacture and had good water tightness. That is, in the figure, holes 51 and 51 drilled in an aluminum plate 5 to be brazed below the through-holes 8 in the plate thickness direction (in FIG. 3, reference numeral 12 is an aluminum thin laminated plate for brazing); Holes formed in aluminum alloy joints 6 'and 7' (joint 6 'of cooling liquid introduction port 6 and joint 7' of cooling liquid discharge port 7) having a square cross section to be brazed therebelow. 6a and 7a are matched, and the cooling liquid introduction port and the cooling liquid discharge port are communicated with the cooling liquid flow passage in the laminated body through the holes 51 and 51 and the holes 6a and 7a.

According to the present invention, a plurality of aluminum plates are joined by brazing to assemble a liquid cooling plate having a built-in cooling liquid flow passage, and an aluminum plate that forms one of the front and back surfaces of the liquid cooling plate is provided. The heat of the electronic component is brought into contact with the component of the electronic device (for example, the heat-generating component itself such as the electronic component or the component heated by the heat-generating component. Equipment components can be cooled by transferring to the cooling liquid in the cooling liquid flow passage. For this reason, for example, the heat of the equipment component is brought about via a metal plate that contacts the equipment component and a metal pipe that forms a cooling liquid flow passage (the liquid passage described in the section “Problems to be solved by the invention”). Compared with the liquid cooling plate of the conventional configuration that transmits the heat to the cooling liquid, the path for guiding the heat of the device parts to the cooling liquid can be shortened, and the cooling efficiency of the device parts can be improved. Further, the liquid cooling plate itself can be easily reduced in size and weight. In the present invention, in particular, the thickness of the liquid cooling plate can be easily reduced as compared with the prior art, thereby reducing the size of electronic equipment incorporating the liquid cooling plate and increasing the mounting density of electronic components and the like. Densification and the like can be easily realized.
Furthermore, as described above, as the brazing, the aluminum laminated brazing is performed by inserting a three-layer or five-layer aluminum thin laminated plate in advance into the overlapping interface of a plurality of aluminum plates. In a state where the pressure is in close contact with each other, it is heated in the range above the liquidus temperature of the brazing material and not exceeding the minimum value of the solidus temperature of each member other than the brazing material. If this is used, pins that cause leakage of the cooling liquid flowing in the cooling liquid flow passage without using expensive equipment such as a vacuum furnace or an airtight atmosphere furnace, and without using flux or inert gas. Excellent brazing free from defects such as holes can be easily realized at low cost. In addition, since it is flux-free brazing, it is not necessary to install ventilation equipment to prevent work environment contamination and purification equipment (equipment for purifying exhaust gas so that halogen-based gas etc. is not discharged). There are also advantages. Compared to the use of equipment such as a vacuum furnace or an atmospheric furnace, this brazing has the advantage that the process is simple and brazing can be performed in a short time, so that high productivity can be realized at low cost. is there. Further, the above-mentioned airless flux lap brazing is a high temperature brazing in the atmosphere, and a dense oxide film (thickness of several μm) is formed on the aluminum surface, so that an aluminum laminate having excellent corrosion resistance can be obtained. There are also advantages. Since the corrosion resistance of the inner surface of the cooling liquid flow passage can be improved in the brazing step, there is an advantage that it is not necessary to separately perform the corrosion resistance treatment.

  Hereinafter, a liquid cooling plate (hereinafter sometimes abbreviated as “liquid cooling plate”) of an electronic device component embodying the present invention and an electronic device in which the liquid cooling plate is incorporated will be described with reference to the drawings. explain.

1 to 4 are views showing a liquid cooling plate 1 according to the present invention, wherein FIG. 1 is an overall perspective view, FIG. 2 is an exploded perspective view, and FIG. 3 is a cooling liquid inlet and a cooling liquid outlet of FIG. 4 is a cross-sectional view showing the relationship between the cooling liquid flow passage and FIG. 4. FIG. 5 is a partially broken perspective view showing a portable personal computer as an example of the electronic device 2 in which the liquid cooling plate 1 is incorporated.
1 to 4, reference numeral 3 is a metal plate with through holes (flow path processing plate), 4 and 5 are metal plates for sealing, 6 is a cooling liquid inlet, and 7 is a cooling liquid outlet.
The metal plate 3 with a through hole and the metal plates 4 and 5 for sealing are aluminum plate materials which consist of aluminum or its base alloy, and between the metal plate 3 with a through hole and the metal plate 4 for sealing, and a metal with a through hole The plate 3 and the sealing metal plate 5 are attached by brazing. Here, as an alloy of the aluminum plate (aluminum base material), any alloy having a melting point higher than the melting point of the brazing filler to be combined may be used. JIS A 1070, 1050, 1100, 1200, 3003, 3203, 3004, 4003, 4004 4104, 4N04, 5005, 5N01, 6061, 6063, 6N01, and the like, and AC1A, AC1B, AC2A, AC2B, AC3A, AC4A, AC4B, AC4C, AC5A, AC8A, AC8B, AC8C, etc. can be preferably used. . However, one of the sealing metal plates 4 and 5 on the front and back sides of the liquid cooling plate 1 (here, the sealing metal plate 4) is an electronic component as a heat generating component mounted on the electronic device 2. 21 (herein referred to as a CPU; hereinafter, a heat-generating component may be referred to as a CPU) is a contact plate, and the sealing metal plate 4 has a particularly high thermal conductivity. Is preferably adopted.

A meandering through hole 31 penetrating in the thickness direction is formed in the metal plate 3 with a through hole. The meandering through hole 31 is a single meandering long hole, and is entirely formed inside the outer peripheral surface 32 of the metal plate 3 with a through hole. That is, there is no opening of the meandering through hole 31 on the outer peripheral surface 32 of the metal plate 3 with the through hole.
The metal plates 4 and 5 for sealing are flat plates. In the figure, the metal plates 4 and 5 for sealing are rectangular plates having the same size as the metal plate 3 with through-holes. However, as the outer size of the metal plates 4 and 5 for sealing, the metal plates 3 with through-holes are used. As long as the meandering through-holes 31 can be closed by overlapping, the size does not necessarily need to match the size of the metal plate 3 with through-holes.

The liquid cooling plate 1 is a metal plate laminate in which the metal plates 4 and 5 for sealing are attached to and integrated with the metal plate 3 with through holes, and the meandering penetration of the metal plate 3 with the through holes. The cooling liquid flow path 8 formed by the hole 31 is incorporated.
The sealing metal plate 5 (the other sealing metal plate) opposite to the contact plate material (sealing metal plate 4) with respect to the CPU 21 is exactly the same at the positions of both ends of the cooling liquid flow passage 8. A through-hole 51 that penetrates the sealing metal plate 5 and communicates with the cooling liquid flow passage 8 is formed. Of the openings of the two through holes 51 on the outer surface side of the sealing metal plate 5 (the opposite side to the surface joined to the metal plate 3 with the through holes), the opening of one through hole 51 is cooled. The liquid introduction opening and the opening of the other through hole 51 function as a cooling liquid discharge opening.
The cooling liquid inlet 6 and the cooling liquid outlet 7 are short pipes here. Specifically, this pipe is made of aluminum or a base alloy thereof, and is attached to the sealing metal plate 5 by brazing, and is connected to the through hole 51 so as to allow liquid to pass therethrough. It is connected.

In FIG. 5, reference numeral 9 denotes a heat radiation side heat sink unit, and 10a and 10b denote liquid circulation passages (here, pipes). The heat radiation side heat sink unit 9 has a built-in liquid flow path (not shown), and the two liquid circulation paths 10a and 10b are for sealing the liquid flow path in the heat radiation side heat sink unit 9 and the CPU 21. The cooling liquid flow path 8 in the liquid cooling plate 1 fixed so as to overlap the metal plate 4 is connected, the liquid flow path in the heat radiation side heat sink unit 9 and the cooling liquid in the liquid cooling plate 1 are connected. A liquid circulation loop circuit 11 is constituted by the flow path 8 and the two liquid circulation paths 10a and 10b. One of the two liquid circulation passages 10a and 10b (liquid circulation passage 10a) is one end of the liquid passage in the heat radiation side heat sink unit 9 and the cooling liquid in the cooling liquid flow passage 8 of the liquid cooling plate 1. The other liquid circulation passage 10b is connected between the introduction port 6 and one end of the liquid flow path in the heat radiation side heat sink unit 9 and the cooling liquid introduction port 6 of the cooling liquid flow passage 8 of the liquid cooling plate 1. Are connected.
The cooling liquid is circulated through the liquid circulation loop circuit 11 by a circulation pump (not shown) built in the heat radiation side heat sink unit 9, and the sealing metal plate 4 from the CPU 21 by the liquid cooling plate 1. After being transferred to the heat dissipation side heat sink unit 9 and cooled by heat exchange in the heat dissipation side heat sink unit 9, the heat is again sent to the cooling liquid flow passage 8 in the liquid cooling plate 1. The CPU 21 is cooled via the liquid cooling plate 1.

As shown in FIG. 10, the heat-sink-side heat sink unit 9 also has a plurality of aluminum members 91 and 92 formed by flux-free brazing in the atmosphere in the same manner as the liquid cooling plate 1 and the manufacturing method thereof according to the present invention. It can be joined to form a unit having a cooling liquid flow passage 93 inside.
In FIG. 10, reference numeral 91 denotes a heat sink, which has a structure in which a large number of fins 91b project from a base plate 91a. At least the base plate 91a of the heat sink 91 is made of aluminum. The heat sink unit 9 shown in FIG. 10 includes a base plate 91 a of the heat sink 91 and an aluminum plate 92 (aluminum base material), and an aluminum thin laminated plate 13 is inserted between the base plate 91 a and the aluminum plate 92. The cooling liquid flow passage 93 is secured between the base plate 91a and the aluminum plate 92 by the thickness of the aluminum thin laminated plate 13 (described later, see FIG. 7). The distance between the base plate 91a and the aluminum plate member 92 can be adjusted by the thickness of the core member 13a of the aluminum thin laminated plate member 13 or the like. The cooling liquid flow passage 93 is formed in a meandering shape by the aluminum thin laminated plate material 13 disposed between the base plate 91 a and the aluminum plate material 92. According to the heat sink side heat sink unit 9, in addition to the effects of the liquid cooling plate 1, such as ensuring water tightness, cost reduction, easy manufacturing, etc., by flux-free brazing in the air using the aluminum thin laminated plate material 13, Since the cooling liquid flow passage 93 is formed directly on the member constituting the heat sink, there is an advantage that the heat radiation efficiency can be improved and the size can be reduced.
10 illustrates the configuration in which the aluminum plate 92 is brazed directly to the base plate 91a of the heat sink 91, the present invention is not limited to this. For example, a plurality of aluminum plates similar to the liquid cooling plate 1 may be used. Needless to say, it is possible to employ a configuration in which the liquid flow path unit assembled by brazing is joined to the base plate 91a of the heat sink 91.

  As brazing between the metal plate 3 with a through-hole and the metal plate 4 for sealing, and between the metal plate 3 with a through-hole and the metal plate 5 for sealing, Shinji Takeno, one of the inventors, As disclosed in Japanese Patent Laid-Open No. 2002-18570 “Flux brazing method without flux of aluminum alloy in the atmosphere” already proposed, aluminum brazing is preferably performed by inserting an aluminum thin laminated plate material. Can be used. With this brazing method, it is easy to ensure high water tightness between the metal plate 3 with through holes and the metal plates 4 and 5 for sealing, and brazing is non-fluxed and inexpensive. And it can be realized easily.

As schematically shown in FIG. 6, this brazing is performed between the metal plate 3 with a through hole and the metal plate 4 for sealing, and between the metal plate 3 with a through hole and the metal plate 5 for sealing. The aluminum thin laminated plate material 12 is inserted and heated in a state where the whole overlapped member is pressed and adhered to be integrated (in FIG. 6, the metal plate 3 with a through hole and the metal plate for sealing 4 However, the brazing between the metal plate 3 with a through hole and the metal plate 5 for sealing is the same). 6 has a three-layer structure, and a skin material 12b, 12c made of an aluminum alloy having a melting point higher than that of the core material 12a is formed on both surfaces of a core material 12a made of a brazing material having a melting point of 600 ° C. or lower. Is provided. Further, at least one of the skin material and the core material contains 0.1 to 6% Mg (mass%, the same applies hereinafter) or 0.01 to 1% Bi.
In addition, the pressure of 0.001 MPa or more is usually required for the degree of pressure-contacting the entire overlapping member.

The aluminum laminated plate material is not limited to a three-layer structure, and for example, as shown in FIG. 7, a five-layer structure (aluminum thin laminated plate material 13) can also be employed.
The thin laminated plate 13 having a five-layer structure has a structure in which intermediate members 13d and 13e are provided between a core member 13a and skin members 13b and 13c on both sides thereof. The intermediate materials 13d and 13e are made of a brazing material having a melting point of 600 ° C. or less, and the core material 13a and the both skin materials 13b and 13c are made of an aluminum alloy having a melting point higher than those of the intermediate materials 13d and 13e. Further, Mg is added in an amount of 0.1 to 6% or Bi is further added in an amount of 0.01 to 1% to any one or more of the skin materials 13b and 13c and the intermediate materials 13d and 13e.

  As described above, as the brazing material of the aluminum thin laminated plates 12 and 13 (the core material 12a of the aluminum thin laminated plate 12 and the intermediate materials 13d and 13e of the aluminum thin laminated plate 13), those having a melting point of 600 ° C. or less are used. However, as the brazing material satisfying this condition, metals such as Zn, Sn, and Bi, and Al—Si, Al—Cu, Al—Cu—Si, Zn—Al, and Al—Ge alloys can be preferably used. The addition of Mg is effective for improving the wettability at the time of melting the brazing material, and effectively contributes to ensuring water tightness between the metal plates 3 and 4 with through holes. If this addition amount is less than 0.1%, the effect is insufficient, and if it exceeds 6%, the addition effect is saturated and meaningless, or there is a problem that workability is lowered, which is not preferable.

  Furthermore, it is preferable to add Bi to any of the constituent members of the aluminum thin laminated plates 12 and 13. In particular, when the aluminum plate material (aluminum base material, metal plate 3 with through hole, metal plate 4 for sealing, metal plate 5 for sealing) to be joined is an alloy containing Mg (in the above example, 3004, 4003, 4004, 4104, 4N04, 5052, etc.), the wettability of the molten brazing material usually deteriorates. However, since Bi functions to prevent this deterioration, it is preferable to add 0.01 to 1.0% of Bi. If the addition amount is 0.01%, the effect is not sufficient, and if it exceeds 1.0%, the effect is saturated, and addition beyond that is meaningless, so 0.01 to 1.0% is desirable.

The total thickness of the aluminum thin laminated plates 12 and 13 to be inserted is usually 0.1 to 1.0 mm.
The clad rate of the brazing material of the aluminum thin laminated plates 12 and 13 (the core material 12a of the aluminum thin laminated plate 12 and the intermediate materials 13d and 13e of the aluminum thin laminated plate 13) is preferably 10 to 80% of the total thickness. If the total plate thickness and the cladding ratio are less than the lower limit, it becomes difficult to manufacture, or brazing is insufficient and the brazing performance is lowered. If the total plate thickness and the upper limit of the cladding ratio are exceeded, it is not preferable because it is not economical due to an unnecessary thickness, or because different types of low melting point metals are inserted, the adverse effect of different alloys increases.

  The two-layer thin laminated plate material 12 has both the skins 12b and 12c, and the core 13a and both the skin materials 13b and 13c in the five-layer thin laminated plate material 13 have a melting point higher than that of the aluminum thin laminated plate materials 12 and 13. There is no particular limitation other than using a high aluminum alloy, for example, JIS A 1070, 1050, 1100, 1200, 3003, 3203, 3004, 4003, 4004, 4104, 4N045005, 5N01, 5052, 5454, 5086, 5083, 6061, 6063, 6N01 and the like can be preferably used.

The reason for heating the brazing joint to be equal to or higher than the liquidus temperature of the brazing material is because it is brazing, and it is necessary to melt the soldering material or brazing material. The reason why the lower limit of the solidus temperature is not exceeded is to prevent deformation and deterioration of members other than the brazing material.
The liquidus temperature of the brazing material is usually 380 to 590 ° C. Solidification of the brazed member may be performed by lowering the temperature, or may be performed by liquid phase diffusion solidification by holding the brazing member for a long time at the brazing temperature. At this time, the holding time is not particularly limited, but is usually preferably about 1 to 10 hours. If it is less than 1 hour, the diffusion is not sufficient, and if it is 10 hours or more, the diffusion is sufficient, and further heating is meaningless.

In this liquid cooling plate 1, the cooling liquid introduction port 6 and the cooling liquid discharge port 7 are made of the same material as the flow path processing plate 3 and the sealing metal plates 4 and 5, and sealed. The metal plate 4 is brazed by the same method as the brazing between the flow path processing plate 3 and the sealing metal plates 4 and 5, and excellent water tightness is secured at the joint. ing. In this case, brazing of the cooling liquid inlet 6 and the cooling liquid outlet 7 to the sealing metal plate 4 and brazing between the flow path processing plate 3 and the sealing metal plates 4 and 5 are performed. There is an advantage that the assembly efficiency of the liquid cooling plate 1 can be improved at the same time.
However, the joining of the cooling liquid inlet 6 and the cooling liquid outlet 7 to the sealing metal plate 4 is not limited to the brazing described above, and for example, welding or the like can be employed.

  In the present invention, the brazing between the aluminum plate members constituting the liquid cooling plate 1 is not limited to the one performed by inserting the thin laminated plate member 12 (or the five-layer thin laminated plate member 13) between the aluminum plate members. At least one of the two aluminum plates to be attached is a three-layer laminated plate base material in which a skin material and an intermediate material are provided on one side of the core material, and the intermediate material of the laminated plate base material has a melting point. A brazing material of 600 ° C. or lower is used, and a skin material and a core material are made of an aluminum alloy whose melting point is higher than that of the intermediate material, and a fluxless brazing method in the atmosphere is realized without using a thin laminated plate material. It is also possible. In this case, 0.1 to 6% of Mg or 0.01 to 1% of Bi is added to at least one of the core material, the skin material, and the intermediate material. Then, the skin surface of the laminated plate base material is placed on the interface side and the aluminum plate base materials are pressed and adhered to each other, and the temperature of the brazing material is higher than the liquidus temperature of each member other than the brazing material. By heating to a range that does not exceed the minimum value of the solidus temperature, flux-free brazing of the aluminum alloy in the atmosphere (high flux brazing in the atmosphere without flux) can be realized.

(Other aspects)
The liquid cooling plate 14 shown in FIGS. 8 and 9 is an example in which a grooved metal plate having a groove 15 a formed on one surface is adopted as the flow path processing plate 15. The liquid cooling plate 14 is an integrated unit of the flow path processing plate 15, the sealing metal plate 16, the cooling liquid introduction port 6, and the cooling liquid discharge port 7. The cooling liquid introduction port 6 and the cooling liquid discharge port 7 are integrated with the metal plate laminate including the stop metal plate 16. Here, as described above, the “concave groove” is a groove formed in a shape in which a part of the metal plate (flow-path processed plate) is deleted.
The sealing metal plate 16 is attached to the surface 15b of the flow path processing plate 15 on which the concave groove 15a is formed, and the concave groove 15a forms a cooling liquid flow path. The material of the flow path processing plate 15 and the sealing metal plate 16 is the same as the flow path processing plate 3 and the sealing metal plates 3 and 4 of the liquid cooling plate 1 described above. The sealing metal plate 16 is joined by brazing similar to that between the flow path processing plate 3 and the sealing metal plates 3 and 4. As shown in FIG. 9, the aluminum thin laminated plate 12 is placed between the flow path processed plate 15 and the sealing metal plate 16 at the brazed portion between the flow path processed plate 15 and the sealing metal plate 16. It is arranged so as to be sandwiched between them.

  Since the liquid cooling plate 14 has a structure in which two aluminum plates (the flow path processing plate 15 and the sealing metal plate 16) are overlapped, the above-described liquid cooling having a structure in which three aluminum plates are stacked. Compared with the plate 1, there is an advantage that the thickness dimension can be reduced.

In addition, this invention is not limited to the above-mentioned embodiment, A various change is possible.
For example, the shape of the aluminum plate constituting the liquid cooling plate is not limited to a rectangular plate shape, and various shapes can be adopted. Moreover, as the aluminum plate material, one having an increased surface area due to the unevenness on the outer surface side and improved heat dissipation can be employed.
FIGS. 2 and 8 show examples in which the meandering through hole and the concave groove are both formed in a U-shape. However, the shape of the meandering through hole and the concave groove is not limited to this, and can be changed as appropriate. Needless to say . Overall pre-SL groove and said meandering through holes, if the channel processing plate configuration which is formed inside the outer peripheral surface of, around the groove or serpentine through holes, constituting the liquid cooling plate The aluminum plate members are brazed and sealed, which is advantageous in that the water tightness of the coolant channel can be easily and reliably ensured.

  The present invention can be widely applied not only to heat dissipation of electronic components such as CPUs, but also to cooling various components of electronic devices such as hard disk drives and display devices such as LEDs.

It is a whole perspective view which shows the liquid cooling plate of embodiment which concerns on this invention. It is a disassembled perspective view which shows the liquid cooling plate of FIG. It is sectional drawing which shows the relationship between the cooling liquid inlet and the cooling liquid discharge port of the liquid cooling plate of FIG. FIG. 2 is a cross-sectional view across a cooling liquid flow path of the liquid cooling plate of FIG. 1. FIG. 2 is a partially cutaway perspective view showing a portable personal computer as an example of an electronic apparatus incorporating the liquid cooling plate of FIG. 1. It is a figure explaining the manufacturing method of the liquid cooling plate of this invention, Comprising: The relationship between the some aluminum plate material (flow-path processed plate, metal plate for sealing) which comprises a liquid cooling plate, and an aluminum thin laminated plate material is modeled. FIG. It is a figure which shows the aluminum thin laminated board material of a 5 layer structure. It is a disassembled perspective view which shows the structure of the liquid cooling plate of the other embodiment which concerns on this invention. It is sectional drawing which shows the structure of the liquid cooling plate of FIG. It is sectional drawing which shows an example of the thermal radiation side heat sink unit.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid cooling plate, 2 ... Electronic device (portable personal computer), 21 ... Heat-emitting component (CPU), 3 ... Channel processing plate (metal plate with a through-hole), 31 ... Serpentine through-hole, 32 ... Channel processing plate 4, 5 ... sealing metal plate, 51 ... through hole (cooling liquid introduction opening, cooling liquid discharge opening), 6 ... cooling liquid introduction port, 7 ... cooling liquid discharge port, 8 ... Cooling liquid flow path, 12 ... Aluminum thin laminated plate material, 12a ... Core material, 12b, 12c ... Skin material, 13 ... Aluminum thin laminated plate material, 13a ... Core material, 13b, 13c ... Skin material, 13d, 13e ... Intermediate material, DESCRIPTION OF SYMBOLS 14 ... Liquid cooling plate, 15 ... Channel processing plate (metal plate with a groove), 15a ... Groove, 16 ... Metal plate for sealing.

Claims (2)

A metal plate laminate in which a plurality of aluminum plates are brazed without flux in the atmosphere, and the metal plate laminate is formed on at least one surface of the aluminum plate in the metal plate laminate. A cooling liquid flow passage extending in a meandering manner in the plate surface direction of the aluminum plate material is formed by a concave groove or a through hole penetrating in the plate thickness direction,
One end and the other end of the cooling liquid flow passage are respectively cooling portions that are openings on the outer surface side of the aluminum plate material of the through holes (51) formed in the aluminum plate material (5) on one side of the metal plate laminate. Connected to the liquid introduction opening and the cooling liquid discharge opening ,
The aluminum plate material (5) on one side of the metal plate laminate has a cooling liquid inlet (6) and a cooling liquid outlet (7), which are tubes made of aluminum or a base alloy thereof, and a joint having a square cross section ( 6 ', 7') are aligned with the through holes (51, 51) of the aluminum plate (5), and the joints are respectively made fluxless in the atmosphere. It is joined by brazing by overlapping brazing,
The aluminum flux brazing in the air between the aluminum plates is performed by previously inserting an aluminum thin laminated plate into the overlapping interface of a plurality of aluminum plates constituting the metal plate laminate, and a cooling liquid Flux brazing in the air to the aluminum plate material of the inlet (6) and the cooling liquid outlet (7) is performed in the atmosphere, and the joint of the cooling liquid inlet (6) and the cooling liquid outlet (7) and the metal plate laminate Aluminum brazing performed by inserting an aluminum thin laminated plate in advance between the aluminum plate (5) on one side of
The aluminum thin laminated plate material is constituted by a core material made of a brazing material having a melting point of 600 ° C. or less and a skin material made of an aluminum alloy having a melting point higher than that of the core material, and any one of the core material and the skin material A three-layer structure in which Mg is added in an amount of 0.1 to 6% (mass%, the same shall apply hereinafter) or Bi is further added in an amount of 0.01 to 1%, or a core material and skin materials on both sides thereof An intermediate material made of a brazing material having a melting point of 600 ° C. or lower is provided between the core material and the both skin materials, which are made of an aluminum alloy having a melting point higher than that of the intermediate material. It has a five-layer structure in which Mg is added to any one or more of 0.1 to 6% or Bi to 0.01 to 1%,
The cooling liquid inlet (6), the cooling liquid outlet (7), and the entire laminated plate are in pressure contact with each other, in the atmosphere, at a temperature higher than the liquidus temperature of the brazing material and for each member other than the brazing material. A liquid cooling plate for electronic device parts, wherein the liquid cooling plate is formed by heating to a temperature range that does not exceed the minimum value of the solidus temperature and then collectively brazing. By joining a plurality of aluminum plate materials made of aluminum or its base alloy by flux-free brazing in the atmosphere, the aluminum plate material is penetrated in the thickness direction of the groove formed in one of the aluminum plate materials or the aluminum plate material. Assembling the metal plate laminate that incorporates the cooling liquid flow path constituted by the through-holes ,
A cooling liquid inlet (6) and a cooling liquid outlet (7), which are pipes made of aluminum or a base alloy thereof, are connected to an aluminum plate (5) on one side of the metal plate laminate, and a joint (6 The holes (6a, 7a) drilled in ', 7') are formed on the outer surface side of the aluminum plate of the through hole (51) drilled in the aluminum plate (5) on one side of the metal plate laminate. The liquid cooling plate is assembled by brazing and joining the joints by means of non-flux lap brazing in the atmosphere so as to match the cooling liquid introduction opening and the cooling liquid discharge opening, which are openings in FIG. A method for manufacturing a liquid cooling plate ,
The aluminum sheet material atmosphere fluxless superposed brazing each other, the interface superposition of a plurality of aluminum sheet material constituting the metal plate laminate superimposed brazing aluminum performed previously inserting the aluminum foil laminated sheet, cooling liquid Flux brazing in the air to the aluminum plate material of the inlet (6) and the cooling liquid outlet (7) is performed in the atmosphere, and the joint of the cooling liquid inlet (6) and the cooling liquid outlet (7) and the metal plate laminate Aluminum brazing performed by inserting an aluminum thin laminated plate in advance between the aluminum plate (5) on one side of
The aluminum thin laminated plate material is constituted by a core material made of a brazing material having a melting point of 600 ° C. or less and a skin material made of an aluminum alloy having a melting point higher than that of the core material, and any one of the core material and the skin material A three-layer structure in which Mg is added in an amount of 0.1 to 6% (mass%, the same shall apply hereinafter) or Bi is further added in an amount of 0.01 to 1%, or a core material and skin materials on both sides thereof An intermediate material made of a brazing material having a melting point of 600 ° C. or lower is provided between the core material and the both skin materials, which are made of an aluminum alloy having a melting point higher than that of the intermediate material. It has a five-layer structure in which Mg is added to any one or more of 0.1 to 6% or Bi to 0.01 to 1%,
The cooling liquid inlet (6), the cooling liquid outlet (7), and the entire laminated plate are in pressure contact with each other, in the atmosphere, at a temperature higher than the liquidus temperature of the brazing material and for each member other than the brazing material. A method for producing a liquid cooling plate, comprising heating to a temperature range that does not exceed a minimum value of the solidus temperature, and collectively brazing.

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