JP4736048B2 - Electronic device cooling plate and method for manufacturing the electronic device cooling plate - Google Patents

Description

  The present invention relates to an electronic device cooling plate excellent in strength and stress corrosion cracking resistance (hereinafter referred to as SCC resistance) and a method for producing the same.

  In order to efficiently cool an electronic device, an electronic device cooling plate used for a large-sized cooling device for electronic devices is required to form a cooling path through which a cooling medium flows. For this reason, for example, when the cooling path is formed by mechanical drilling with a drill or the like, there is a limit to the distance that can be drilled with respect to the diameter of the hole, making it difficult to manufacture a large electronic device cooling plate. In addition, since only simple holes can be formed, it is difficult to provide high heat exchange performance.

  Therefore, in order to form a cooling path with a complicated shape in the interior, two or more aluminum alloy plates in which grooves serving as the cooling path are previously arranged are laminated and joined together by brazing. It was considered that a method of forming a cooling path having a complicated shape is suitable for manufacturing a large electronic device cooling plate. For this reason, an aluminum alloy plate for producing a laminated mold by fluxless brazing in the air has been proposed (see Patent Document 1). However, in the air brazing of the 7000 series aluminum alloy, an oxide film mainly composed of MgO is formed on the surface of the brazing material, so that the brazing property is lowered and the joining strength is lowered or the joining is not performed. A malfunction occurs. In addition, due to the influence of moisture contained in the atmosphere, the hydrogen concentration in the obtained laminated material tends to increase, which causes a problem in SCC resistance. For this reason, it is required to perform the brazing operation in a vacuum.

  Moreover, the electronic device cooling plate used for the large-sized cooling device for electronic devices is heavy, and when the electronic device is used in a transportation machine such as a railway vehicle or an aircraft, it is necessary to reduce the weight of the electronic device cooling plate itself. Become. On the other hand, high strength is required for the cooling plate in order to reduce the weight and prevent the occurrence of damage accidents.

Furthermore, when the electronic device cooling plate is used in the large cooling device for electronic devices, it is necessary to reliably prevent leakage of the cooling medium from the cooling plate. Therefore, the aluminum alloy material used for the cooling plate must also have excellent bondability. Therefore, brazing containing 3.0-4.5 wt% Zn, 0.3-0.8 wt% Mg, 0.2-0.9 wt% Mn, 0.2-0.5 wt% Cr Aluminum alloy (Patent Document 2), 3.0-4.0 wt% Zn, 0.3-0.8 wt% Mg, 0.2-0.9 wt% Mn, 0.05-0.5 wt An aluminum alloy for brazing (Patent Document 3) containing% Zr has been proposed. However, these alloys do not provide sufficient strength after brazing, and a brazing aluminum alloy with higher strength is required to further reduce the weight of the cooling plate.
JP 2005-264316 A JP 58-153754 JP 58-21146 A

  The present invention solves the above-described problems and provides an electronic device cooling plate excellent in strength and SCC resistance while reducing the weight of the electronic device cooling plate and a method for manufacturing the same.

  In order to solve the above problem, the electronic device cooling plate of the present invention has a cooling path for circulating a cooling medium therein. That is, it is composed of two or more 7000 series aluminum alloy metal plate bodies, and a continuous groove is provided on the surface of the metal plate body, followed by vacuum brazing while sandwiching the sheet-like brazing material, and thereafter At least by cooling and joining together, a cooling path through which the cooling medium circulates is formed inside the joined two or more metal plate bodies.

Specifically, as a first feature, it is composed of two laminated 7000 series aluminum alloy metal plate bodies,
In one or both of the opposing surfaces of the two metal plates to be laminated, continuous grooves are disposed alone or symmetrically,
Sandwiching a sheet-like brazing material between the two opposing metal plates,
A cooling path in which a cooling medium circulates in the inside of the two metal plates joined together by vacuum brazing the two metal plates in a vacuum furnace and then joining them together by cooling. Is formed.

As a second feature, it is composed of three laminated 7000 series aluminum alloy metal plate bodies,
In one or both of the opposing surfaces of the first and second metal plates to be laminated, continuous grooves are disposed alone or symmetrically, and
On one or both of the opposing surfaces of the second and third metal plates to be laminated, the same continuous grooves are disposed independently or symmetrically,
A sheet-like brazing material is sandwiched between the opposing first and second metal plates and between the opposing second and third metal plates;
The three metal plate bodies are vacuum brazed in a vacuum furnace, and then cooled and then integrally joined together, so that a cooling medium circulates in the inside of the joined three metal plate bodies. Is formed.

As a third feature, it is composed of three laminated 7000 series aluminum alloy metal plate bodies,
In the second metal plate to be laminated, continuous slit grooves penetrating both surfaces are provided, and in each of the other two metal plates, each surface facing the second metal plate is flat. Or on the surface provided with continuous grooves symmetrical to the slit grooves,
A sheet-like brazing material is sandwiched between the opposing first and second metal plates and between the opposing second and third metal plates;
The three metal plate bodies are vacuum brazed in a vacuum furnace, and then cooled and then integrally joined together, so that a cooling medium circulates in the inside of the joined three metal plate bodies. Is formed.

  The cooling performed in the manufacturing process of the electronic device cooling plate may be performed in a vacuum brazing furnace or outside the furnace. That is, the cooling in the present invention is performed as follows, for example. First, in the case of the furnace, when the furnace temperature reaches the target temperature, fresh air is introduced into the furnace by opening the door of the furnace, blowing air with a fan, or the like, or leaving the furnace closed. This is done by introducing an inert gas into the inside. On the other hand, in the case of outside the furnace, the product is directly carried out of the furnace, and further performed by blowing a fan or the like. As a result, the effect of the cooling is that the method of introducing air by opening the door in the furnace, the method of blowing air with a fan after opening the door in the furnace, the method of carrying out of the furnace, the outside of the furnace After carrying out, it becomes high in order of the method of blowing with a fan. The product after cooling is increased in strength by natural aging, and the required strength characteristics can be obtained.

  As a fourth feature, the cooling performed after vacuum brazing is performed at an average cooling rate of 200 ° C./h or more and 1000 ° C./h or less up to 200 ° C. in consideration of each of the first to third features. It is assumed to be rapid cooling and then cooled to room temperature.

  By the way, the cooling performed after the vacuum brazing is performed from the brazing temperature to 200 ° C. at an average cooling rate of 200 ° C./h or more and 1000 ° C./h or less, and then cooled to room temperature. This is because when the average cooling rate from the brazing temperature to 200 ° C. is less than the lower limit of the above range, coarse precipitation of Zn, Mg, and Cu elements occurs, and sufficient strength cannot be obtained. On the other hand, when the upper limit of the above range is exceeded, the SCC resistance is reduced, and a large residual stress is generated inside the cooling plate, and SCC is generated when used for a long period of time. This is because it will not be fulfilled.

  As a fifth feature, based on each of the first to fourth features, a 7000 series aluminum alloy material that is a metal plate constituting the electronic device cooling plate is made of Zn: 4.1-10. 0.0% (mass%, the same applies hereinafter), Mg: 0.9 to 2.0%, Cu: 0.05 to 0.30%, Mn: 0.05% to 0.50%, Cr : 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance is Al and inevitable impurities.

  By the way, in the 7000 series aluminum alloy material of the metal plate constituting the electronic device cooling plate, the range of the content of Zn, Mg, Cu, and Mn, Cr, Zr is specified as described above. This is for a reason.

First, since Zn acts together with Mg to improve the strength, its content must be 4.1 to 10.0%. That is, if the content is less than the lower limit of the above range, the effect of improving the strength is small. Conversely, if the content exceeds the upper limit, the melting point is lowered, so that it is easy to melt during brazing.
Therefore, the more preferable content range of Zn is 4.1 to 7.5%, and the most preferable content range is 4.5 to 5.0%.

Next, since Mg acts together with Zn to improve the strength, its content must be 0.9 to 2.0%. That is, if the content is less than the lower limit of the above range, the effect of improving the strength is small, and conversely if the content exceeds the upper limit, the melting point is lowered, so that it is easy to melt at the time of brazing and the joint strength in brazing is lowered. .
Therefore, the more preferable content range of Mg is 1.0 to 2.0%, and the most preferable content range is 1.4 to 1.9%.

And since Cu functions so that SCC resistance may be improved by adding trace amount, its content is preferably 0.05 to 0.30%. That is, if the content is less than the lower limit or exceeds the upper limit, the SCC resistance decreases. Furthermore, if Cu is contained in excess of the upper limit, the quenching sensitivity is increased, so that sufficient quenching cannot be performed by cooling performed after vacuum brazing, resulting in a decrease in strength.
Therefore, the more preferable Cu content range is 0.05 to 0.20%, and the most preferable content range is 0.10 to 0.20%.

In addition, Mn, Cr, and Zr are all elements that are selectively contained. By containing one or more, Mn, Cr, and Zr can refine crystal grains, improve brazing properties, and also improve SCC resistance. Therefore, the contents must be Mn: 0.05 to 0.50%, Cr: 0.05 to 0.30%, and Zr: 0.05 to 0.20%, respectively. That is, if any element is less than the lower limit of the range, the brazing property and the SCC resistance are lowered, and if it exceeds the upper limit, a coarse compound is formed at the time of casting, causing a casting crack, This is because cracks are likely to occur during rolling or hot extrusion, which hinders the production of the material.
Therefore, the more preferable content ranges of Mn, Cr and Zr are Mn: 0.15 to 0.50%, Cr: 0.05 to 0.25%, Zr: 0.10 to 0.20%, The most preferable content ranges are Mn: 0.30 to 0.50%, Cr: 0.10 to 0.20%, and Zr: 0.12 to 0.18%.

  By the way, Si, Fe, and Ti are listed as unavoidable impurities, but the content of each impurity element is preferably 0.30% or less for Si, 0.35% or less for Fe, and 0.05% or less for Ti. It is.

  As a sixth feature, based on each of the first to fifth features, the brazing material to be used in the vacuum brazing process is an Al-Si-based or Al-Si-Mg-based alloy plate. A plate, or those clad on both surfaces of an aluminum plate or an aluminum alloy plate, and brazing temperature in a vacuum furnace is set to 570 ° C. or more and 600 ° C. or less.

  As described above, brazing is performed in a vacuum furnace at a brazing temperature of 570 ° C. or higher and 600 ° C. or lower, but the time required for temperature increase (temperature increase rate) is not particularly limited. However, when the brazing temperature is less than the lower limit of the above range, the brazing material is insufficiently melted, so that the bonding strength is lowered or the bonding is not performed. On the other hand, when the brazing temperature exceeds the upper limit of the above range, melting of the metal plate body of the 7000 series aluminum alloy, which is the brazing material, is not preferable. Furthermore, since the solution treatment of the brazing material is simultaneously performed in this vacuum brazing process, in a 7000 series aluminum alloy metal plate containing Zn, Mg, Cu elements, Zn, Mg at 450 ° C. or higher. In this case, a sufficient solid solution state is obtained in the process of raising the temperature to the brazing temperature, but a more preferable brazing temperature range is 580 ° C. or more and 590 ° C. or less.

  By the way, in the vacuum brazing process, in order to set the brazing temperature to 600 ° C. or lower, the liquidus temperature of the brazing material to be used needs to be set to 600 ° C. or lower. The Si content of a single plate of Si—Mg-based alloy plates, or those clad on both surfaces of an aluminum plate or an aluminum alloy plate is 8.0% or more.

  Here, the aluminum plate used as the core material when the brazing material is the clad material is suitably an aluminum or aluminum alloy plate. When an Al-Si alloy plate is used as the skin material, an Al-Mn-Mg alloy is used. A plate can be suitably employed as the core material. Further, when an Al—Si—Mg alloy is used as a skin material, an Al—Mn alloy or an Al—Mn—Mg alloy can be suitably used as the core material.

  Furthermore, as a seventh feature, the thickness of the plurality of 7000 series aluminum alloy metal plates stacked is 10 mm or more. The reason why the thickness of the metal plate of the 7000 series aluminum alloy is 10 mm or more is to ensure the surface workability at the time of joining and the strength of the electronic device cooling plate as a product.

  In addition, the manufacturing method of the metal plate body itself of 7000 series aluminum alloy material brazed is demonstrated. First, for example, a 7000 series aluminum alloy ingot having the above composition is produced by, for example, a DC casting method, and the obtained ingot is homogenized. This homogenization treatment is generally performed at a temperature of 400 ° C. or higher and 550 ° C. or lower. Next, the homogenized ingot is processed into a required size by hot rolling or hot extrusion. After hot rolling or hot extrusion, cold rolling may be performed to increase the accuracy of the plate thickness, and the material is made larger than the required size and adjusted to the required size by cutting. May be. In this way, a metal plate of a 7000 series aluminum alloy material having a thickness of 10 mm or more is obtained.

  The present invention provides an electronic device cooling plate that can be efficiently cooled because it can form a cooling path corresponding to the heat generation location of the electronic device, and that is lightweight, excellent in strength and SCC resistance. Therefore, the cooling device provided with the electronic device cooling plate is suitably used for railway vehicles and aircraft.

Hereinafter, an electronic device cooling plate according to an embodiment of the present invention will be described with reference to FIGS.
In addition, these Examples are for demonstrating one preferable embodiment of this invention, Comprising: This invention is not restrict | limited by this.

  FIG. 1 is a cross-sectional view showing before and after vacuum brazing joining of an electronic device cooling plate 1 composed of two metal plate bodies according to the first embodiment of the present invention. That is, 2 is a metal plate body of a 7000 series aluminum alloy material, 3 is a flat surface, 4 is a continuous groove, 5 is a sheet-like brazing material, 6 is a joining layer, and 7 is formed by joining the metal plate bodies 2 and 2. A cooling path through which a cooling medium such as a propylene glycol aqueous solution circulates.

Here, the first embodiment is manufactured as follows. That is, the continuous groove | channel 4 is arrange | positioned in one surface of one metal plate body 2 among the two metal plates 2 and 2 of 7000 series aluminum alloy with a thickness of 10 mm or more laminated | stacked. One surface of the other metal plate 2 is a flat surface 3.
Then, the brazing material 5 in the form of an Al—Si sheet is sandwiched between the two metal plate bodies 2, 2 while the surface on which the continuous grooves 4 are disposed and the plane 3 are opposed to each other. [See FIG. 1 (a)].
Further, the two metal plates 2 and 2 are joined by vacuum brazing in a vacuum furnace at a brazing temperature of 580 ° C. and then rapidly cooling to at least 200 ° C. at an average cooling rate of 500 ° C./h. The layer 6 is formed and joined together.
As a result, a cooling path 7 is formed inside the two metal plates 2 and 2 joined together (see FIG. 1B), and both ends of the cooling path 7 are connected to the metal plates 2 and 2 respectively. A cooling medium circulates in the cooling path 7 in communication with a suction hole and a discharge hole (not shown) provided in the cooling path.

  Then, when the cooling medium circulates in the cooling path 7 formed inside the electronic device cooling plate 1, the metal plate bodies 2 and 2 constituting the electronic device cooling plate 1 are cooled. Therefore, the electronic device to which the metal plate bodies 2 and 2 are attached is cooled by taking the generated heat by the metal plate bodies 2 and 2.

  FIG. 2 is a cross-sectional view of the electronic device cooling plate 1 ', which is a modification of the first embodiment of the present invention, before and after vacuum brazing. That is, continuous grooves 4 similar to those of the first embodiment are symmetrically disposed on both opposing surfaces of the two metal plates 2 and 2 to be laminated. Then, the sheet-like brazing material 5 is sandwiched while the respective surfaces of the two metal plates 2 and 2 in which the grooves 4 are symmetrically arranged are opposed to each other [see FIG. The bonding layer 6 is formed by vacuum brazing and rapid cooling under the same conditions as in the first embodiment, and bonded together. As a result, a cooling path 7 'having a larger cross-sectional area is formed inside the electronic device cooling plate 1' [see FIG. 2 (b)].

  FIG. 3 shows a second embodiment of the present invention and is a cross-sectional view showing before and after vacuum brazing joining of an electronic device cooling plate 1a composed of three laminated metal plate bodies 2, 2, 2. That is, 2 is a metal plate of a 7000 series aluminum alloy material, 3 is a flat surface, 4a is a continuous groove, 5 is a brazing material in the same sheet form as in the first embodiment, 6 is a bonding layer, 7a is the metal plate 2 This is a cooling path through which a cooling medium formed by joining 2 and 2 circulates.

Here, the electronic device cooling plate 1a according to the second embodiment is manufactured as follows. That is, the electronic device cooling plate 1a of the second embodiment is composed of three 7000 series aluminum alloy metal plate bodies 2, 2, and 2 to be laminated. Among them, in one metal plate 2 that is the second sheet in the stacking order, continuous grooves 4a are provided on both surfaces thereof. One surface of the other two metal plate bodies 2 and 2 is a flat surface 3. It should be noted that a continuous groove symmetrical to the continuous groove 4a may be provided on one surface of the other two first and third metal plate bodies 2, 2 as the flat surface 3. Good.
Then, the sheet-like brazing material 5 is sandwiched between the two metal plate bodies 2 facing each other from both sides of the metal plate body 2 in which the groove 4a is disposed. [See FIG. 3 (A)].
Further, the three metal plates 2, 2, 2 are vacuum brazed in a vacuum furnace under the same conditions as in the first embodiment of the present invention, and then rapidly cooled to thereby form the bonding layer 6. Are formed and joined together.
As a result, a cooling path 7a in which the cooling medium circulates is formed inside the three metal plate bodies 2, 2 and 2 that are integrally joined (see FIG. 3B). At that time, cooling paths 7a and 7a are formed on both sides of the metal plate 2 with the grooves 4a provided on both sides. The cooling paths 7a are independent from each other, and suction holes and discharges are separately provided at both ends. Even if each of the cooling paths 7a and 7a is communicated with each other through holes (not shown) or through the holes passing through the metal plate 2, the cooling paths 7a and 7a are communicated with each other. The remaining ends of 7a and 7a may be communicated with a suction hole and a discharge hole (not shown), respectively.
And this electronic device cooling plate 1a was attached to the electronic device cooling plate 1a by circulating a cooling medium inside, similarly to the electronic device cooling plate 1, 1 'which is the first embodiment of the present invention. Heat is taken from the electronic device and cooling is performed, and cooling can be performed on both sides.

FIG. 4 is a cross-sectional view of the electronic device cooling plate 1a ′, which is a modification of the second embodiment of the present invention, before and after vacuum brazing. That is, among the three metal plates 2, 2, 2, which are stacked, the first and third metal plates 2, 2 which are the first and the third in the stacking order are continuously symmetrical to each other. A groove 4a is provided.
Then, the sheet-like brazing material 5 is formed with the other one metal plate 2 as the center and the surfaces of the first and third metal plates 2 and 2 on which the grooves 4a are disposed are opposed to each other. [See FIG. 4 (a)].
Further, vacuum brazing and rapid cooling are performed under the same conditions as in the first embodiment.
As a result, two-stage cooling paths 7a and 7a are formed inside the electronic device cooling plate 1a 'of the present invention [see FIG. 4 (b)]. In that case, the independence or communication of the two-stage cooling paths 7a, 7a and the relationship between the suction holes and the discharge holes are the same as in the case of FIG. Then, heat is taken from the electronic device to which the electronic device cooling plate 1a ′ is attached to perform cooling, and the electronic device can be cooled on both sides thereof.

FIG. 5 shows a third embodiment of the present invention, and is a cross-sectional view showing before and after vacuum brazing joining of an electronic device cooling plate 1a ″ composed of three laminated metal plate bodies 2, 2, 2. That is, 2 is a metal plate body made of a 7000 series aluminum alloy material, 3 is a flat surface, 8 is a single metal plate body 2, and is a slit groove continuous through both surfaces, and 5 is the same sheet shape as in the first embodiment. A brazing material, 6 is a joining layer, and 7b is a cooling path through which a cooling medium formed by joining the metal plate bodies 2, 2, 2 circulates.
Then, with the metal plate body 2 in which the continuous slit grooves 8 are disposed as the center, the plane sheet 3 of the other two metal plate bodies 2 and 2 is opposed to each other, and an Al—Si-based sheet-like brazing material 5 is provided. [See FIG. 5 (a)].
Further, the three metal plates 2, 2, 2 are subjected to vacuum brazing and rapid cooling under the same conditions as in the first embodiment.
As a result, a cooling path 7b having a large cross-sectional area is formed inside the electronic device cooling plate 1a ″ of the present invention (see FIG. 5B), and both ends of the cooling path 7 are metal plate bodies on both sides. The cooling medium circulates through the cooling passage 7 in communication with suction holes and discharge holes (not shown) provided in the second and second holes 2. Therefore, the electronic device cooling plate 1a ″ is also used in the second embodiment of the present invention. As with certain electronic device cooling plates 1a, 1a ', a cooling medium is circulated inside the cooling path 7 so that heat is taken from the electronic device to which the electronic device cooling plate 1a "is attached to perform cooling. In addition, the electronic device can be cooled on both sides of the electronic device cooling plate 1a ″.
Although one surface of the two metal plate bodies 2 and 2 on both sides is a flat surface, a cooling path 7b having a larger cross-sectional area can be formed by similarly arranging continuous grooves symmetrical to the slit grooves 8. It can also be formed inside the electronic device cooling plate 1a ″.

  Therefore, the 7000 series aluminum alloy of the metal plate constituting the electronic device cooling plate 1 according to the present invention contains Zn, Mg, Cu and at least one of Mn, Cr, and Zr within a predetermined content range. In addition, the effect was confirmed by tensile strength and SCC resistance.

  Therefore, the test materials of the examples of the present invention were produced as follows. That is, for the aluminum alloys A to F having the chemical components shown in Table 1, an ingot having a thickness of 300 mm, a width of 500 mm, and a length of 1000 mm is produced by a DC casting method, and homogenized at 450 ° C. for 10 hours. Two pieces of brazing samples each having a thickness of 25 mm, a width of 400 mm, and a length of 600 mm were produced by hot rolling, and two pieces were used as a set for brazing test. Then, the surface to be brazed is mechanically chamfered to a depth of 1 mm, and a groove having a width of 2 mm and a depth of 2 mm is provided over the entire length of one of the two sheets. Five were mechanically arranged at 10 mm intervals. Then, a brazing material having a thickness of 0.25 mm of 4045 alloy is sandwiched between two samples of the same alloy each paired, and two blocks made of stainless steel having a thickness of 50 mm, a width of 600 mm, and a length of 800 mm The sample was sandwiched by placing it vertically and inserted into a vacuum brazing furnace. In brazing, the temperature was raised to 585 ° C. in 3 hours, and when the temperature reached 585 ° C., cooling to room temperature was started in the furnace. At this time, the average cooling rate from 585 ° C. to 200 ° C. was performed at 600 to 700 ° C./h, and then cooled to room temperature and then kept at room temperature for 30 days.

  On the other hand, the test material of the comparative example was manufactured for the 7000 series aluminum alloys G to M having the chemical components shown in Table 2 by the same manufacturing method as in the present invention.

And about the test material of each Example of the said invention of this application, and the test material of a comparative example, tensile property and SCC resistance were evaluated on the conditions shown below.
First, the tensile properties are such that a No. 10 test piece defined in JIS Z 2201 is prepared so that the sheet width direction matches the tensile test direction, and a tensile test is performed at room temperature to determine the tensile strength, yield strength, and elongation. taking measurement. When collecting the test piece, the surface is sampled within a depth range of 20 mm so as not to include the brazed portion.
Next, the SCC resistance was obtained by preparing a C-ring test piece shown in FIG. 2 of Annex 5 of JIS H 8711 so that the direction in which the tensile stress was generated coincided with the thickness direction. 90% is loaded under the conditions described in Annex 5 of FIG. The test solution used is a 3.5% NaCl aqueous solution in accordance with JIS H8711, and the SCC test is conducted for a maximum of 30 days by repeating the cycle of immersion for 10 minutes and drying for 50 minutes at 25 ° C. Then, the surface of the test piece is visually observed once a day, and when a crack having a length of 3 mm or more can be confirmed, it is determined that the crack has occurred, and the number of days on which the crack has occurred is measured.

  As a result, as shown in Table 3, the test materials 1 to 6 according to the test materials of the examples of the present invention all show high strength characteristics, and cracks are also observed in the 30-day SCC test. There wasn't. On the other hand, the test materials 11-17 by the test material of a comparative example came to show in Table 4. That is, the strength of the test material 11 was low because Zn and Mg were less than the lower limits. Since the test material 12 contained Zn and Mg in excess of the upper limit, the material melted during brazing and could not be brazed. Since the test material 13 had Cu less than the lower limit, the SCC resistance was lowered. Since all of Mn, Cr and Zr were less than the lower limit of the test material 14, the SCC resistance was lowered. Since the test material 15 contained Mn exceeding the upper limit, a coarse compound was formed at the time of casting, and a casting crack was generated. Since the test material 16 contained Cr exceeding the upper limit, a coarse compound was formed at the time of casting, a crack was generated by hot rolling, and a sample could not be prepared. Since the test material 17 contained Zr exceeding the upper limit, a coarse compound was formed at the time of casting, a crack was generated by hot rolling, and a sample could not be produced.

  From the above, the composition of the 7000 series aluminum alloy used for the metal plate 2 constituting the electronic device cooling plate in the present invention contains Zn, Mg, Cu within each predetermined range according to claim 5 and Mn Further, the effect of containing one or more of Cr, Zr, and the balance Al and inevitable impurities was clearly confirmed.

  Next, the effect of the vacuum brazing process and the subsequent rapid cooling conditions in manufacturing the electronic device cooling plate 1 according to the present invention was confirmed by the tensile strength and the SCC resistance.

The test material of each example of the present invention is 25 mm in thickness, 400 mm in width by performing casting, homogenization treatment, and hot rolling on the basis of the above manufacturing method for the alloy A having the chemical components shown in Table 1. Eight pieces of brazing samples having a length of 600 mm were produced, and two pieces were used as one set of brazing test samples. Then, the surface to be brazed is mechanically chamfered to a depth of 1 mm, and a groove having a width of 2 mm and a depth of 2 mm is provided over the entire length of one of the two sheets. Five were mechanically arranged at intervals of 10 mm. Then, a brazing material of 4045 alloy thickness 0.2mm is sandwiched between the two samples in each pair, and two stainless steel blocks 50mm thick, 600mm wide and 800mm long are placed up and down Thus, the sample was sandwiched and inserted into a vacuum brazing furnace. Then, with the temperature rising time set to 3 hours, one set of each was brazed under the conditions shown in Table 5 and rapidly cooled to room temperature outside the furnace, and then kept at room temperature for 30 days. Then, test materials 7 to 10 were prepared from the test materials, and the tensile properties and the SCC resistance were evaluated under the same conditions.

  On the other hand, the test material of the comparative example was manufactured by the same manufacturing method as the test material of each example of the present invention except that only the brazing conditions and the cooling conditions were changed as shown in Table 6. Thereafter, test materials 18 to 21 were prepared from the test materials, and the tensile properties and the SCC resistance were evaluated under the same conditions.

  As a result, as shown in Table 7, all of the test materials 7 to 10 of the examples of the present invention showed high strength characteristics, and no cracks were observed in the 30-day SCC test. On the other hand, the test materials 18 to 21 of the comparative examples are as shown in Table 8. That is, the test material 18 could not be brazed because the brazing temperature was lower than the lower limit. Since the brazing temperature of the test material 19 exceeded the upper limit, the material melted during the brazing process and could not be brazed. The test material 20 had low strength because the cooling temperature after brazing was less than the lower limit. Since the cooling rate after brazing of the test material 21 exceeded the upper limit, the SCC resistance was lowered.

  From the above, in the present invention, the effect of defining the vacuum brazing condition and the rapid cooling condition was clearly confirmed.

  The electronic device cooling plate of the present invention is capable of appropriate cooling according to the heat generation location of the electronic device, is light and strong, and has excellent SCC resistance. Can be applied to cooling any electronic equipment placed.

It is sectional drawing before and behind joining of 1st Example of the electronic device cooling plate of this invention. It is sectional drawing before and behind joining of the modification of 1st Example of the electronic device cooling plate of this invention. It is sectional drawing before and behind joining of 2nd Example of the electronic device cooling plate of this invention. It is sectional drawing before and behind joining of the modification of 2nd Example of the electronic device cooling plate of this invention. It is sectional drawing before and behind joining of 3rd Example of the electronic device cooling plate of this invention.

Explanation of symbols

1, 1 ', 1a, 1a', 1a "Electronic equipment cooling plate 2 Metal plate body 3 Plane 4 Groove 5 Sheet-like brazing material 3 Joining layer 7, 7 ', 7a, 7b Cooling path 8 Slit groove

Claims (9)

Two layers , Zn: 4.1-10.0% (mass%, the same applies hereinafter), Mg: 0.9-2.0%, Cu: 0.05-0.30%, Further, 7000 containing at least one of Mn: 0.05% to 0.50%, Cr: 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance being Al and inevitable impurities. Composed of a metal plate of an aluminum alloy,

In one or both of the opposing surfaces of the two metal plates to be laminated, continuous grooves are disposed alone or symmetrically,

Sandwiching a sheet-like brazing material between the two opposing metal plates,

A cooling path in which a cooling medium circulates in the inside of the two metal plates joined together by vacuum brazing the two metal plates in a vacuum furnace and then joining them together by cooling. An electronic device cooling plate characterized by comprising:

Three layers , Zn: 4.1-10.0% (mass%, the same applies hereinafter), Mg: 0.9-2.0%, Cu: 0.05-0.30%, Further, 7000 containing at least one of Mn: 0.05% to 0.50%, Cr: 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance being Al and inevitable impurities. Composed of a metal plate of an aluminum alloy,

In one or both of the opposing surfaces of the first and second metal plates to be laminated, continuous grooves are disposed alone or symmetrically, and

On one or both of the opposing surfaces of the second and third metal plates to be laminated, the same continuous grooves are disposed independently or symmetrically,

A sheet-like brazing material is sandwiched between the opposing first and second metal plates and between the opposing second and third metal plates;

The three metal plate bodies are vacuum brazed in a vacuum furnace, and then cooled and then integrally joined together, so that a cooling medium circulates in the inside of the joined three metal plate bodies. An electronic device cooling plate characterized by comprising:

Three layers , Zn: 4.1-10.0% (mass%, the same applies hereinafter), Mg: 0.9-2.0%, Cu: 0.05-0.30%, Further, 7000 containing at least one of Mn: 0.05% to 0.50%, Cr: 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance being Al and inevitable impurities. Composed of a metal plate of an aluminum alloy,

In the second metal plate to be laminated, continuous slit grooves penetrating both surfaces are provided, and in each of the other two metal plates, each surface facing the second metal plate is flat. Or on the surface provided with continuous grooves symmetrical to the slit grooves,

A sheet-like brazing material is sandwiched between the opposing first and second metal plates and between the opposing second and third metal plates;

The three metal plate bodies are vacuum brazed in a vacuum furnace, and then cooled and then integrally joined together, so that a cooling medium circulates in the inside of the joined three metal plate bodies. An electronic device cooling plate characterized by comprising:
Two layers, Zn: 4.1-10.0% (mass%, the same applies hereinafter), Mg: 0.9-2.0%, Cu: 0.05-0.30%, Further, 7000 containing at least one of Mn: 0.05% to 0.50%, Cr: 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance being Al and inevitable impurities. Made of a metal plate of an aluminum alloy,

In one or both of the opposing surfaces of the two metal plates to be laminated, continuous grooves are disposed singly or symmetrically,

Sandwiching a sheet-like brazing material between the two opposing metal plates,

The two metal plates are vacuum brazed in a vacuum furnace,

After that, it is cooled to an average cooling rate of 200 ° C./h or more and 1000 ° C./h or less to 200 ° C., and then integrally joined by cooling to room temperature,

A cooling path through which a cooling medium circulates is formed inside the joined two metal plates.

The manufacturing method of the electronic device cooling plate characterized by the above-mentioned.

Three layers, Zn: 4.1-10.0% (mass%, the same applies hereinafter), Mg: 0.9-2.0%, Cu: 0.05-0.30%, Further, 7000 containing at least one of Mn: 0.05% to 0.50%, Cr: 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance being Al and inevitable impurities. Made of a metal plate of an aluminum alloy,

In one or both of the opposing surfaces of the first and second metal plates to be laminated, continuous grooves are disposed singly or symmetrically,

In one or both of the opposing surfaces of the second and third metal plates to be laminated, the same continuous grooves are disposed alone or symmetrically,

A sheet-like brazing material is sandwiched between the opposing first and second metal plates and between the opposing second and third metal plates;

The three metal plates are vacuum brazed in a vacuum furnace,

After that, it is cooled to an average cooling rate of 200 ° C./h or more and 1000 ° C./h or less to 200 ° C., and then integrally joined by cooling to room temperature,

A cooling path through which a cooling medium circulates is formed inside the joined three metal plates.

The manufacturing method of the electronic device cooling plate characterized by the above-mentioned.

Three layers, Zn: 4.1-10.0% (mass%, the same applies hereinafter), Mg: 0.9-2.0%, Cu: 0.05-0.30%, Further, 7000 containing at least one of Mn: 0.05% to 0.50%, Cr: 0.05 to 0.30%, Zr: 0.05 to 0.20%, and the balance being Al and inevitable impurities. Made of a metal plate of an aluminum alloy,

In the second metal plate to be laminated, a continuous slit groove penetrating both sides is disposed, In the other two metal plate bodies, each surface facing the second metal plate body is provided with a flat surface or a continuous groove symmetrical to the slit groove,

A sheet-like brazing material is sandwiched between the opposing first and second metal plates and between the opposing second and third metal plates;

The three metal plates are vacuum brazed in a vacuum furnace,

After that, it is cooled to an average cooling rate of 200 ° C./h or more and 1000 ° C./h or less to 200 ° C., and then integrally joined by cooling to room temperature,

A cooling path through which a cooling medium circulates is formed inside the joined three metal plates.

The manufacturing method of the electronic device cooling plate characterized by the above-mentioned.

In the vacuum brazing process, the sheet-like brazing material to be used is a single plate of an Al-Si-based or Al-Si-Mg-based alloy plate, or clad on both sides of an aluminum plate or an aluminum alloy plate. The method for manufacturing an electronic device cooling plate according to any one of claims 4 to 6, wherein a brazing temperature in a vacuum furnace is set to 570 ° C or higher and 600 ° C or lower.

4. The electronic device cooling plate according to claim 1, wherein the plurality of stacked 7000 series aluminum alloy metal plate bodies have a thickness of 10 mm or more. 5.

The method for manufacturing an electronic device cooling plate according to any one of claims 4 to 7, wherein the plurality of laminated 7000 series aluminum alloy metal plate bodies have a thickness of 10 mm or more.

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