JP2012156302A - Liquid cooled jacket and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid cooled jacket securing strength which withstands bolt fastening.SOLUTION: A liquid cooled jacket 1 is formed by fastening a seal body 30 sealing an opening of a recessed part 11 to a jacket body 10, having the recessed part 11 where a heat transport fluid flows, with bolts. The jacket body 10 and the seal body 30 respectively include peripheral parts 16, 33 where through holes 17, 37 are formed for bolt fastening. At least one of the jacket body 10 and the seal body 30 includes a heat radiation part 31 having a contact surface 32 contacting a cooled body, and the material strength of the peripheral part 33 is higher than the material strength of the heat radiation part 31.

Description

  The present invention relates to a liquid cooling jacket and a manufacturing method thereof.

  In recent years, as the performance of electronic devices typified by personal computers has improved, the amount of heat generated by a CPU (heat generating body) mounted has increased, and cooling of the CPU has become increasingly important. Conventionally, air-cooled fan type heat sinks have been used to cool the CPU, but problems such as fan noise and cooling limit in the air-cooling system have been highlighted. A liquid cooling jacket as shown in Document 1 has attracted attention. The liquid cooling jacket is used not only for the CPU but also for cooling power devices such as IGBT (Insulated Gate Bipolar Transistor) chips and power modules.

  This liquid cooling jacket includes a jacket body having a recess through which a heat transport fluid flows, and a sealing body that seals the opening of the recess, and the jacket body and the sealing body are joined by friction stir welding. The liquid cooling jacket is manufactured. In addition, joining of a jacket main body and a sealing body is not necessarily limited to friction stir welding, and there exist some which join a jacket main body and a sealing body by bolt fastening as shown to patent document 2. As shown in FIG.

JP 2009-166079 A JP 2008-311550 A

  By the way, the method of joining the jacket body and the sealing body is appropriately selected in consideration of the shape, cost, etc., but when bolt fastening is selected as in Patent Document 2, bolt fastening is performed. The strength of the peripheral edge becomes a problem.

  That is, since the jacket body or the sealing body to which the object to be cooled such as a CPU is attached places importance on another conductivity, pure aluminum (such as JIS1050) or aluminum alloy (such as JIS6063) having high thermal conductivity is selected. . However, these alloys have a relatively low strength, and there is a problem in that plastic deformation may occur during bolt fastening.

  Therefore, the present invention has been devised to solve the above problems, and an object thereof is to provide a liquid cooling jacket capable of withstanding bolt fastening and a method for manufacturing the same.

  The present invention for solving the above-described problems is directed to a liquid cooling jacket configured by bolting a sealing body for sealing an opening of the recess to a jacket main body having a recess through which a heat transport fluid flows. The main body and the sealing body include a peripheral portion in which a through hole for fastening a bolt is formed, and at least one of the jacket main body and the sealing body includes a heat radiating portion having a contact surface with a body to be cooled. In addition, the material strength of the peripheral portion is configured to be higher than the material strength of the heat dissipation portion.

  According to such a configuration, even if the material strength of the heat radiating portion is low, the peripheral portion has a high material strength, so it can withstand bolt fastening and prevent plastic deformation.

  In the present invention, it is preferable that the heat dissipating part is composed of a member different from the peripheral part.

  According to such a configuration, a liquid cooling jacket can be easily created, and a heat radiating portion having a high thermal conductivity and a peripheral portion having a high strength can be clearly distinguished.

  Furthermore, the present invention is configured such that a jacket body having a recess through which a heat transport fluid flows is bolted to a sealing body that seals the opening of the recess, and at least one of the jacket body and the sealing body is A liquid cooling jacket manufacturing method comprising: a heat dissipating part having a contact surface with a body to be cooled; and a peripheral part provided on an outer periphery of the heat dissipating part and having a bolt fastening through hole formed therein. After the electronic component which is the object to be cooled is brazed, the peripheral portion made of a heat-treatable aluminum alloy whose material strength is higher than that of the heat radiating portion is joined to the heat radiating portion.

  According to such a method, since the peripheral portion is not affected by heat due to brazing of the electronic component, it is possible to prevent a decrease in material strength of the peripheral portion, and the peripheral portion can obtain high material strength.

  Further, the present invention is configured by fastening a sealing body that seals the opening of the recess to a jacket body having a recess through which a heat transport fluid flows, and at least one of the jacket body and the sealing body is A liquid cooling jacket manufacturing method comprising: a heat dissipating part having a contact surface with a body to be cooled; and a peripheral part provided on an outer periphery of the heat dissipating part and having a bolt fastening through hole formed therein. After the peripheral portion made of a non-heat treatment type aluminum alloy having higher material strength is joined to the heat radiating portion, an electronic component which is a body to be cooled is brazed to the heat radiating portion.

  According to such a method, since the peripheral portion is formed of a non-heat-treatable aluminum alloy, the strength of the peripheral portion does not decrease even when receiving heat from the brazing of the electronic component, and the peripheral portion is made of a high material. Strength can be obtained.

  Furthermore, the present invention is configured such that a jacket body having a recess through which a heat transport fluid flows is bolted to a sealing body that seals the opening of the recess, and at least one of the jacket body and the sealing body is A liquid cooling jacket manufacturing method comprising: a heat dissipating part having a contact surface with a body to be cooled; and a peripheral part provided on an outer periphery of the heat dissipating part and having a bolt fastening through hole formed therein. And the peripheral portion are formed of the same member, and the peripheral portion is age-hardened after the heat-radiating portion is soldered to the electronic component that is the object to be cooled.

  In addition, the thermal radiation part and a peripheral part should just be formed with the same member, and it does not ask | require whether it forms after integrally forming or after forming separately. According to the above method, even if the peripheral portion is affected by the heat of the soldering of the electronic component and the strength is reduced, the strength can be recovered by the age hardening treatment. In addition, it is possible to ensure the strength that can withstand bolt fastening at the periphery while securing the properties.

  According to the present invention, it is possible to ensure strength that can withstand bolt fastening.

It is the disassembled perspective view which looked at the liquid cooling jacket which concerns on 1st embodiment from diagonally upward. It is the disassembled perspective view which looked at the liquid cooling jacket which concerns on 1st embodiment from diagonally downward. It is the disassembled perspective view which looked at the liquid cooling jacket which concerns on 2nd embodiment from diagonally upward. (A) is an expansion perspective view of a thermal radiation part, (b) is an expansion perspective view of a peripheral part. It is the disassembled perspective view which looked at the liquid cooling jacket which concerns on 3rd embodiment from diagonally upward. It is an expansion perspective view of a sealing body.

(First embodiment)
The liquid cooling jacket according to the first embodiment is a component of a cooling system mounted on an electronic device such as a personal computer, for example, and is a component that cools a CPU (electronic component) that is an object to be cooled. The cooling system includes a liquid cooling jacket in which a CPU as a heating element is attached at a predetermined position, a radiator (heat dissipating means) that releases heat transported by the cooling water (heat transport fluid), and a micropump that circulates the cooling water. (Heat transport fluid supply means), a reserve tank that absorbs expansion / contraction of cooling water due to temperature changes, a flexible tube that connects them, and cooling water that transports heat are mainly included. For example, an ethylene glycol antifreeze is used as the cooling water. And if a micropump act | operates, cooling water will circulate through these apparatuses. In the present embodiment, the object to be cooled is described as a CPU, but the liquid cooling jacket is used not only for the CPU but also for cooling power devices such as IGBT chips and power modules.

  As shown in FIGS. 1 and 2, the liquid cooling jacket 1 is configured by fixing a sealing body 30 to a jacket main body 10 having a recess 11 (see FIG. 2) by bolt fastening. The recess 11 is partially opened while cooling water (heat transport fluid) for transporting heat generated by the CPU 2 to the outside flows. The sealing body 30 seals the opening 12 (see FIG. 2) of the recess 11. In the present embodiment, a case where the CPU 2 (an object to be cooled) is attached to the sealing body 30 is taken as an example.

  The liquid cooling jacket 1 is configured such that the CPU 2 is attached to the center of the sealing body 30 via a heat diffusion sheet (not shown). The liquid cooling jacket 1 receives the heat generated by the CPU 2 when the cooling water flows through the liquid cooling jacket 1 with the CPU 2 attached, and exchanges heat with the cooling water flowing through the inside. Thereby, the liquid cooling jacket 1 transmits the heat received from the CPU 2 to the cooling water, and as a result, the CPU 2 is efficiently cooled. The thermal diffusion sheet is a sheet for efficiently transferring the heat of the CPU 2 to the jacket body 10 and is formed of a metal having high thermal conductivity such as copper, for example.

  The jacket body 10 is a shallow box that is open on one side (lower side in the present embodiment), and has a bottom wall 13 that is a bottom surface of the recess 11 and a peripheral wall 14 that is a peripheral surface of the recess 11. is doing. Such a jacket main body 10 is produced by die casting, casting, forging or the like, for example. The jacket body 10 is made of aluminum or an aluminum alloy and is reduced in weight. The jacket body 10 is formed of a heat-treatable aluminum alloy having high strength (tensile strength) (for example, “JIS6061-T6”, “JIS6061-T651”, etc.). The jacket body 10 may be formed of a non-heat treatment type aluminum alloy having high strength (for example, “JIS 3000 series” aluminum-manganese (Al—Mn) series alloy). The strength of the aluminum alloy may be higher than the strength at which the peripheral edge portion 16 does not cause plastic deformation by bolt fastening.

  A pair of wall portions 14 a facing each other of the peripheral wall 14 of the concave portion 11 of the jacket body 10 are formed with through holes 15 for circulating cooling water through the concave portion 11. The through-hole 15 has a circular cross section and is formed in the intermediate portion in the depth direction of the recess 11. In addition, the shape and position of the through-hole 15 are not restricted to this, It can change suitably according to the kind and flow volume of cooling water.

  A frame-shaped peripheral edge 16 is formed on the outer periphery of the recess 11 of the jacket body 10. The peripheral edge portion 16 is a portion for fixing the sealing body 30 by bolting. The peripheral edge portion 16 is formed so as to surround the recess 11, and a plurality of bolt fastening through holes (hereinafter referred to as “bolt through holes”) 17 are formed. Between adjacent bolt through holes 17, 17, a notch 18 is formed in which the outer peripheral edge of the peripheral edge 16 is recessed inward. Thereby, weight reduction of the jacket main body 10 main body can be achieved.

  The sealing body 30 includes a heat dissipating part 31 having a contact surface 32 with the CPU 2 and a frame-shaped peripheral part 33 formed so as to surround the heat dissipating part 31. The sealing body 30 is formed from aluminum or an aluminum alloy. In this embodiment, the heat radiating part 31 and the peripheral part 33 are each comprised from another member. Moreover, the thermal radiation part 31 and the peripheral part 33 are formed separately, and are mutually joined.

  The heat radiating portion 31 is configured by a rectangular plate-like member that is smaller than the area of the opening 12 of the recess 11. The contact surface 32 is provided in the center part of the outer surface of the heat radiating part 31 which becomes the outer side of the liquid cooling jacket 1, and is formed flat. On the other hand, a plurality of fins 35, 35... Are formed on the surface of the heat radiating portion 31 facing the recess 11 of the jacket body 10.

  The heat dissipation part 31 and the plurality of fins 35 are integrally formed by cutting a block formed of aluminum or an aluminum alloy. Thereby, heat is favorably transmitted between the heat radiating portion 31 and the fins 35, 35. Note that the manufacturing method is not limited to this. For example, a member having a cross-sectional shape including the heat radiating portion 31 and the plurality of fins 35, 35,... It may be cut into pieces.

  The plurality of fins 35, 35... Are arranged parallel to each other and orthogonal to the heat radiating portion 31. The fins 35, 35... Are arranged so as to extend in a direction orthogonal to the wall portion 14 a in which the through hole 15 is formed. The fin 35 has a height (depth) dimension (length in the Z-axis direction in FIG. 1) equivalent to the depth dimension of the recess 11, and the tip of the fin 35 contacts the bottom wall 13 of the recess 11. It is like that. Thus, in a state where the sealing body 30 is attached to the jacket body 10, a cylindrical space is partitioned by the heat radiating portion 31 of the sealing body 30, the adjacent fins 35 and 35, and the bottom wall 13 of the recess 11. The space functions as a flow path through which the cooling water flows. Further, the fins 35, 35... Have a length dimension (length in the X-axis direction in FIG. 1) that is shorter than the length dimension of one side of the recess 11, and both ends of the fins 35, 35. Each of the wall portions 14a, 14a is configured to be spaced from the inner wall surface by a predetermined distance. As a result, in a state where the sealing body 30 is attached to the jacket main body 10, the space between the outer ends of the fins 35, 35... And the wall portion 14 a of the peripheral wall 14 of the recess 11 extends from the through hole 15 to the fin. The flow path header portion that extends in the direction orthogonal to the extending direction of 35 (the Y-axis direction in FIG. 1) is configured.

  The peripheral portion 33 is made of a frame-like member joined to the outer peripheral portion of the heat radiating portion 31. A plurality of equivalent bolt through holes (bolt fastening through holes) 37 are formed in the peripheral portion 33 at positions corresponding to the bolt through holes 17 in the peripheral portion 16. The peripheral portion 33 has the same outer peripheral shape as the peripheral portion 16 of the jacket main body 10, and a notch portion 38 in which the outer peripheral edge of the peripheral portion 33 is recessed inward between the adjacent bolt through holes 37, 37. Is formed. Thereby, weight reduction of the sealing body 30 main body can be achieved. Furthermore, when the jacket main body 10 and the sealing body 30 are joined, other parts can be inserted into the notches 18 and 38, so that it is easy to engage with the parts around the liquid cooling jacket 1, The layout can be improved.

  The peripheral edge 33 has a wider width than the peripheral edge 16 of the jacket body 10, and the inner peripheral edge of the peripheral edge 33 protrudes inward from the inner peripheral edge of the peripheral edge 16 (periphery of the opening 12). . As a result, a gap is formed between the fin 35 and the peripheral wall 14 of the recess 11, and the gap between the wall portions 14 a, 14 a and the fin 35 becomes a flow path header portion. The inner peripheral edge of the peripheral portion 33 has the same shape as the outer peripheral edge of the heat radiating portion 31, and the heat radiating portion 31 is mounted inside the peripheral portion 33.

  By the way, as the material of the peripheral portion 33, a plurality of types of aluminum alloys having high strength can be selected, but the process of attaching the CPU 2 as the object to be cooled to the heat radiating portion 31 according to the material of the aluminum alloy is a manufacturing process. It may be limited at which point in time. Moreover, the material of the peripheral part 33 and the joining method of the thermal radiation part 31 and the peripheral part 33 may be limited by a manufacturing process. Below, the relationship between the kind of selected aluminum alloy and a manufacturing method is demonstrated.

  As a first case, the peripheral edge portion 33 is made of a heat-treatable aluminum alloy having high strength (tensile strength) (for example, aluminum-magnesium-silicon (Al-Mg) such as “JIS6061-T6” and “JIS6061-T651”). The case of forming with (Si) alloy) will be described. This is a case where the manufacturing method is limited by the material of the peripheral portion 33. In addition, the intensity | strength of an aluminum alloy should just be more than the intensity | strength of the grade which the peripheral part 33 does not raise | generate a plastic deformation by bolt fastening.

  In this case, after the CPU 2 is brazed (soldered or brazed) to the heat radiating portion 31, a manufacturing method is adopted in which the heat radiating portion 31 and the peripheral edge portion 33 are joined to each other. According to such a manufacturing method, when the CPU 2 is brazed to the heat dissipating part 31, the peripheral part 33 is not joined to the heat dissipating part 31, so that the peripheral part 33 is not affected by the heat of brazing. Therefore, even if it is heat processing type aluminum alloy, since the material intensity | strength does not fall, the sealing body 30 can be formed, maintaining the high intensity | strength of the peripheral part 33. FIG. In addition, since the heat radiating portion 31 is not required to have a strength against the bolt fastening, aluminum-magnesium--such as pure aluminum (for example, “JIS1050”) or an aluminum alloy having a high thermal conductivity (for example, “JIS6063”). Silicon (Al-Mg-Si) -based alloy) may be employed. In addition, since the heat radiating part 31 is formed integrally with the fin 35, an aluminum alloy having high machinability (for example, JIS6000 series (aluminum-magnesium-silicon (Al-Mg-Si) series such as “JIS6063-T5”)). ) Alloy) is even more preferred.

  In addition, since it is not necessary to consider the thermal effect of brazing for the joining of the heat radiating part 31 and the peripheral part 33, it may be bonded using an adhesive or the like that provides the necessary bonding strength.

  As a second case, a case will be described in which the heat sink 31 and the peripheral edge 33 are joined to each other, and then the CPU 2 that is the object to be cooled is brazed to the heat sink 31. This is a case where the material of the peripheral portion 33 is limited due to the manufacturing method.

  In this case, when the CPU 2 is brazed to the heat radiating portion 31, since the peripheral edge portion 33 is already joined to the heat radiating portion 31, the peripheral edge portion 33 receives the heat of brazing. Therefore, the peripheral portion 33 is made of a material that can resist the heat of brazing. That is, the peripheral portion 33 is made of a non-heat-treatable aluminum alloy having high strength (tensile strength) (for example, “JIS 3000 series” aluminum-manganese (Al—Mn) alloy or “JIS 5000 series” aluminum-magnesium ( Al—Mg) alloy). The strength of this aluminum alloy should just be more than the intensity | strength of the grade which the peripheral part 33 does not raise | generate a plastic deformation by bolt fastening. By adopting such a material, since the material strength of the peripheral edge portion 33 does not decrease even when subjected to the heat of brazing, the sealing body 30 is formed while maintaining the high strength of the peripheral edge portion 33. can do. In this case as well, as in the first case, the heat dissipating part 31 is not required to have a strength against bolt fastening, so pure aluminum (for example, “JIS1050” or the like) or simply an aluminum alloy with high thermal conductivity ( For example, an aluminum-magnesium-silicon (Al—Mg—Si) -based alloy such as “JIS6063” may be employed. In addition, since the heat radiating part 31 is formed integrally with the fin 35, an aluminum alloy having high machinability (for example, JIS6000 series (aluminum-magnesium-silicon (Al-Mg-Si) series such as “JIS6063-T5”)). ) Alloy) is even more preferred.

  Furthermore, since the joining part of the heat radiating part 31 and the peripheral part 33 receives the heat of brazing in a subsequent process, joining of metals such as friction stir welding, brazing, and laser welding is performed. According to this, even if the joining portion receives the heat of brazing, the joining strength does not decrease.

  The sealing body 30 formed as described above is arranged so that the peripheral edge portion 33 abuts on the peripheral edge portion 16 of the jacket body 10, and a bolt (not shown) is inserted through each of the bolt through holes 17 and 37. Tighten with a nut (not shown). At this time, since each of the peripheral portions 16 and 33 has a material strength capable of resisting bolt fastening, it is possible to perform tightening with an appropriate strength and to prevent plastic deformation of the peripheral portions 16 and 33. Can do. Therefore, the sealing performance of the joint portion between the jacket main body 10 and the sealing body 30 can be improved, and the liquid cooling jacket 1 with high water tightness can be obtained.

  In particular, in the first case, the manufacturing procedure is determined according to the material of the peripheral portion 33 of the sealing body 30, so that the peripheral portion 33 is not subjected to the heat of brazing of the CPU 2 and the material strength thereof is increased. Can be maintained. In the second case, since the material of the peripheral portion 33 and the joining method of the heat radiating portion 31 and the peripheral portion 33 are determined according to the manufacturing procedure, the peripheral portion 33 receives the heat of brazing of the CPU 2. However, the material strength can be maintained, and the bonding strength between the heat dissipating portion 31 and the peripheral portion 33 can be maintained.

  Further, since the heat radiating portion 31 is formed of pure aluminum or aluminum alloy having high thermal conductivity, which is a separate member from the peripheral portion 33, the cooling performance of the CPU 2 is improved. Furthermore, since a large number of fins 35 are formed of the same material, the cooling performance is further enhanced.

(Second embodiment)
Next, the configuration of the liquid cooling jacket according to the second embodiment will be described. As shown in FIGS. 3 and 4, the liquid cooling jacket 1 ′ is configured by fixing a sealing body 30 ′ to the jacket body 10 by bolt fastening, as in the first embodiment. In the present embodiment, the step portions 40 and 41 are formed at the joint portion between the heat radiation portion 31 ′ and the peripheral portion 33 ′ of the sealing body 30 ′. Below, the structure of the level | step-difference parts 40 and 41 is demonstrated. In addition, since the structure of another part is the same as that of 1st embodiment, it attaches | subjects the same code | symbol and abbreviate | omits description.

  The step portion 40 of the heat radiating portion 31 ′ is formed over the entire outer periphery. The step portion 40 is configured such that a step is formed at the middle portion in the thickness direction of the plate material. The heat dissipating part 31 ′ is configured such that the width dimension and the length dimension on the fin 35 side are small, and when the fin 35 is placed on the upper side, the stepped part 40 becomes stepped.

  The step portion 41 of the peripheral edge portion 33 ′ is formed over the entire inner peripheral edge. As shown in FIG. 4A, the step portion 41 is configured such that a step appears at an intermediate portion in the thickness direction of the plate material. The inner peripheral edge of the peripheral edge portion 33 ′ protrudes inward with a thickness of the upper half when arranged in the state of FIG. 3, and is configured to mesh with the stepped portion 40 of the heat radiating portion 31 ′.

  As described above, the stepped portion 40 is formed on the outer peripheral edge of the heat radiating portion 31 ′, and the stepped portion 41 is formed on the inner peripheral edge of the peripheral portion 33 ′. It becomes a positioning guide when joining the peripheral portion 33 ′ and the joining work becomes easy. Further, since the stepped portions 40 and 41 are engaged with each other and fixed to each other, the stepped portions 40 and 41 serve as a holding jig for the rotary tool in the friction stir welding, and the jig can be reduced and the friction stir welding can be performed. It can be done easily.

  In the present embodiment, the heat radiating portion 31 ′ is configured such that the width dimension and the length dimension on the fin 35 side are small. However, the present invention is not limited to this, and the width dimension on the fin 35 side and You may comprise so that a length dimension may become large. In this case, the peripheral portion 33 ′ may be joined with the front and back reversed.

(Third embodiment)
Next, the configuration of the liquid cooling jacket according to the third embodiment will be described. As shown in FIGS. 5 and 6, the liquid cooling jacket 1 ″ is configured by fixing a sealing body 30 ″ to the jacket main body 10 by bolt fastening as in the first embodiment. In the present embodiment, the thin plate portion 45 is formed inside the peripheral portion 33 ″ of the sealing body 30 ″, and the thin plate portion 45 constitutes the bottom portion of the housing recess 46. The housing recess 46 is a portion that houses the heat radiating portion 31 ". Hereinafter, the configuration of the heat radiating portion 31" and the peripheral edge portion 33 "of the sealing body 30" will be described. In addition, since the structure of another part is the same as that of 1st embodiment, it attaches | subjects the same code | symbol and abbreviate | omits description.

  The thin plate portion 45 inside the peripheral edge portion 33 ″ is formed to have a thickness approximately half the thickness of the peripheral edge portion 33 ″. One surface (lower surface in FIG. 5) of the thin plate portion 45 is configured to be flush with one surface (lower surface in FIG. 5) of the peripheral portion 33 ″. Is formed at a right angle to the surface of the thin plate portion 45. Note that the angle of the side wall surface of the housing recess 46 with respect to the surface of the thin plate portion 45 is not limited to a right angle. In this case, the outer peripheral surface of the heat radiating portion 31 ″ may also be inclined according to the inclination angle of the side wall surface of the housing recess. Form.

  The thickness of the heat dissipating part 31 ″ is the same as the depth of the accommodating recess 46, and when the heat dissipating part 31 ″ is accommodated in the accommodating recess 46, the surface of the heat dissipating part 31 ″ (in FIGS. 5 and 6). The upper surface) and the surface of the peripheral portion 33 ″ (the upper surface in FIGS. 5 and 6) are configured to be flush with each other (see FIG. 6).

  According to such a configuration, since the heat radiation portion 31 ″ is accommodated in the accommodation recess 46 inside the peripheral edge portion 33 ″ and the joining operation is performed, the heat radiation portion 31 ″ can be easily positioned and the heat radiation portion The joining operation can be performed with 31 ″ fixed. Further, the thin plate portion 45 serves as a pressing tool for the rotary tool in the friction stir welding, and the friction stir welding can be easily performed.

(Other embodiment of a manufacturing method)
In said 1st thru | or 3rd embodiment, the thermal radiation part 31 and the peripheral part 33 are each formed in the different body which consists of a separate member, and the material strength of the peripheral part 33 becomes higher than the material strength of the thermal radiation part 31. In the present embodiment, the heat radiating portion and the peripheral portion are formed of the same member, and after soldering the electronic component that is the object to be cooled to the heat radiating portion, the peripheral portion is age-hardened, The material strength of the peripheral portion 33 is made higher than the material strength of the heat radiating portion 31.

  In addition, as long as the thermal radiation part and the peripheral part are formed with the same member, they may be integrally formed, or may be joined and integrated after being formed separately. When the heat dissipating part and the peripheral part are formed separately, the electronic parts are connected and integrated before brazing. In the present embodiment, a case where the heat radiating portion and the peripheral portion are integrally formed will be described as an example.

  In the present embodiment, the heat radiating portion and the peripheral portion are made of a heat-treatable aluminum alloy (for example, “JIS6000 series” aluminum-magnesium-silicon (Al—Mg—Si) having high strength (tensile strength) and high thermal conductivity. ) Series alloy) etc. to form a sealing body. Then, an electronic component such as an IC chip is brazed to the sealing body (the heat radiating portion and the peripheral portion). For example, the soldering is performed by attaching an electronic component to the contact surface of the heat radiating portion and inserting the electronic component into a reflow furnace. At this time, the peripheral edge portion is also inserted into the reflow furnace, so that denaturation occurs and the material strength decreases. Therefore, age hardening is performed by locally heating the peripheral edge. The age-hardening treatment is artificially performed by, for example, locally heating by high-frequency electromagnetic induction heating or laser irradiation heating and then cooling.

  Thus, the material strength of a peripheral part is recovered by performing the age hardening process of a peripheral part. At this time, the material strength may be recovered to such a level that the peripheral portion 33 does not cause plastic deformation by bolt fastening. According to this manufacturing method, since the material strength of the peripheral portion that has been lowered by brazing is recovered by age hardening, the material strength of the peripheral portion is higher than the material strength of the heat dissipation portion. And a peripheral part will have the material intensity | strength which can oppose a bolt fastening, and can prevent the plastic deformation. Therefore, the sealing performance of the joint portion between the jacket body and the sealing body can be improved, and a liquid-cooled jacket with high water tightness can be obtained.

  Further, since the age hardening treatment is locally performed, the processing time can be greatly shortened compared with the case of performing the entire age hardening treatment, and the processing efficiency is improved. Furthermore, since the heat radiation part and the peripheral part are formed of the same member, the formation can be performed efficiently. In particular, when the heat dissipating part and the peripheral part are integrally formed, the joining work is omitted.

  As mentioned above, although embodiment of this invention was described, embodiment of this invention is not limited to this, In the range which does not deviate from the meaning of this invention, it can change suitably, For example, said 2nd embodiment. Then, the step portions 40 and 41 are respectively formed on the outer peripheral portion of the heat radiating portion 31 ′ and the inner peripheral portion of the peripheral portion 33 ′, and the heat radiating portion 31 ′ and the peripheral portion 33 ′ are engaged with each other. Is not to be done. For example, you may make it form the taper part which mutually meshes with the outer peripheral part of a thermal radiation part, and the inner peripheral part of a peripheral part.

  Moreover, in the said embodiment, although CPU2 is fixed to the sealing body 30, it is not limited to this, You may fix CPU to a jacket main body, a jacket main body and a sealing body You may make it fix CPU to both. In this case, the jacket main body (and the sealing body) is provided with a heat radiating portion, and the material strength of the peripheral portion of the jacket main body is preferably higher than the material strength of the heat radiating portion.

1 Liquid cooling jacket 2 CPU (cooled object)
DESCRIPTION OF SYMBOLS 10 Jacket body 11 Recessed part 30 Sealing body 31 Heat radiation part 32 Contact surface 33 Peripheral part 1 'Liquid cooling jacket 30' Sealing body 31 'Heat radiation part 33' Peripheral part 1 "Liquid cooling jacket 30" Sealing body 31 "Heat radiation part 33 "periphery

Claims (5)

In a liquid cooling jacket configured by bolting a sealing body that seals an opening of the recess to a jacket body having a recess through which a heat transport fluid flows,
The jacket main body and the sealing body each include a peripheral portion in which a through hole for fastening a bolt is formed,
At least one of the jacket main body and the sealing body includes a heat radiating portion having a contact surface with the body to be cooled,
A liquid cooling jacket characterized in that the material strength of the peripheral edge portion is higher than the material strength of the heat dissipation portion. The liquid cooling jacket according to claim 1, wherein the heat dissipating part is formed of a member different from the peripheral part. The jacket body having a recess through which the heat transport fluid flows is configured by bolting a sealing body that seals the opening of the recess,
At least one of the jacket main body and the sealing body includes a heat radiating portion having a contact surface with a cooled body, and a peripheral portion provided on the outer peripheral portion thereof and having a through hole for fastening bolts. A method of manufacturing a cold jacket,
After soldering the electronic component that is the object to be cooled to the heat radiating part,
The manufacturing method of the liquid cooling jacket characterized by joining the said peripheral part which consists of heat processing type aluminum alloy whose material strength is higher than the said thermal radiation part to the said thermal radiation part. The jacket body having a recess through which the heat transport fluid flows is configured by bolting a sealing body that seals the opening of the recess,
At least one of the jacket main body and the sealing body includes a heat radiating portion having a contact surface with a cooled body, and a peripheral portion provided on the outer peripheral portion thereof and having a through hole for fastening bolts. A method of manufacturing a cold jacket,
After joining the peripheral portion made of a non-heat-treatable aluminum alloy having a material strength higher than that of the heat dissipation portion, to the heat dissipation portion,
A method for manufacturing a liquid cooling jacket, comprising: soldering an electronic component that is a body to be cooled to the heat radiating portion. The jacket body having a recess through which the heat transport fluid flows is configured by bolting a sealing body that seals the opening of the recess,
At least one of the jacket main body and the sealing body includes a heat radiating portion having a contact surface with a cooled body, and a peripheral portion provided on the outer peripheral portion thereof and having a through hole for fastening bolts. A method of manufacturing a cold jacket,
The heat radiating part and the peripheral part are formed of the same member,
After soldering the electronic component that is the object to be cooled to the heat radiating part,
The manufacturing method of the liquid cooling jacket characterized by carrying out the age hardening process of the said peripheral part.

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