JP2014133256A - Brazing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a brazing structure capable of ensuring the optimum thickness of a brazing filler material, when a metal member and a metal member are joined by the brazing filler material.SOLUTION: In a joining step, a part of slurries 22 enters between metallic powders of a powder lump 14, and Ni-based brazing filler materials included in the slurries 22 are immersed in the metallic powders of the power lamp 14 to eutectically join the Ni-based brazing filler material on surfaces of the metallic powders. The slurries 22 are dammed by the powder lamp 14 (a dam effect). Therefore, the optimum thickness of a joint brazing filler material 12 can be ensured.

Description

  The present invention relates to a brazing structure used for joining a metal member and a metal member.

  Patent Document 1 describes a configuration in which a release agent is disposed at a bonding interface of a substrate when the substrate and the heat sink are bonded with a brazing material. By this release agent, a non-bonded region that is not bonded to the substrate and the heat sink is formed, and by providing this non-bonded region, thermal stress at the time of bonding with the brazing material is relieved.

JP 2008-235672 A

  However, in the conventional configuration, when the metal member and the metal member are joined with the brazing material, the movement of the brazing material cannot be controlled, and the brazing material flows out to the outside of the joining interface with the metal member. There is. As a result, an appropriate thickness of the brazing material may not be ensured.

  The subject of this invention is ensuring the appropriate thickness of a brazing material, when joining a metallic member and a metallic member with a brazing material.

  The brazing structure according to claim 1 of the present invention is sandwiched between a pair of metal members facing each other and diffused and joined to each of the metal members, and sandwiched between the pair of metal members and the joint. And a composite brazing material that is disposed on the periphery of the brazing material and includes a brazing material of the same type as the brazing material constituting the joining brazing material and a metal powder.

  According to the said structure, the composite brazing material is arrange | positioned at the periphery of the joining brazing material. Thereby, when joining a metal member and a metal member with a joining brazing material, the appropriate thickness of a joining brazing material is securable.

  The brazing structure according to claim 2 of the present invention is the brazing structure according to claim 1, wherein the composite brazing material is impregnated with the brazing material of the same kind as the brazing material constituting the joining brazing material in the metal powder. It is characterized by that.

  According to the above configuration, the composite brazing material is impregnated with the same kind of brazing material as that constituting the joining brazing material in the metal powder. For this reason, when joining a metal member and a metal member with a joining brazing material, a composite brazing material becomes a support | pillar and the support | pillar effect (spacer effect) is exhibited, and the distance between metal members may be made into a predetermined value. it can.

  The brazing structure according to claim 3 of the present invention is the brazing structure according to claim 1 or 2, wherein the composite brazing material is of the same type as the brazing material constituting the joining brazing material on the surface of the metal powder. The brazing material is eutectic bonded.

  According to the above configuration, the composite brazing material is formed by eutectic bonding the same kind of brazing material as the brazing material constituting the joining brazing material on the surface of the metal powder. Thereby, the column effect is effectively exhibited by improving the liquidus temperature of the composite brazing material, and the distance between the metal members can be effectively set to a predetermined value.

  The brazing structure according to a fourth aspect of the present invention is the brazing structure according to any one of the first to third aspects, wherein the composite brazing material constitutes the joining brazing material for the metal powder. The volume ratio of the same kind of brazing material as the material is 25% or more and 50% or less.

  According to the above configuration, in the composite brazing material, the volume ratio of the brazing material to the metal powder is 25% or more and 50% or less. For this reason, precipitation of the additive resulting from compositional segregation inside the composite brazing material layer can be suppressed.

  The brazing structure according to claim 5 of the present invention is the brazing structure according to any one of claims 1 to 4, wherein the height of the composite brazing material is equal to the height of the joining brazing material. It is characterized by.

  According to the said structure, the height of a composite brazing material is made equivalent to the height of a joining brazing material. Thereby, when one metal member is pressed against the other metal member and the pair of metal members are joined with the joining brazing material, the lateral displacement amount that the one metal member is laterally displaced with respect to the other metal member is suppressed. Can do.

  A brazing structure according to a sixth aspect of the present invention is the brazing structure according to any one of the first to fifth aspects, wherein the composite brazing material is continuously formed along the periphery of the joining brazing material. It is characterized by being.

  According to the above configuration, since the composite brazing material is continuously formed along the periphery of the joining brazing material, it effectively suppresses the joining brazing material from flowing out of the joining interface with the metal member. can do.

  The brazing structure according to a seventh aspect of the present invention is the brazing structure according to any one of the first to fifth aspects, wherein the composite brazing material is discontinuously along the periphery of the joining brazing material. It is formed.

  According to the above configuration, since the composite brazing material is formed discontinuously along the periphery of the joining brazing material, even if the composite brazing material cannot be formed continuously, the joining brazing material is a metal member. It can suppress flowing out to the outer side of the joining interface.

  The brazing structure according to an eighth aspect of the present invention is the brazing structure according to any one of the first to fifth aspects, wherein the composite brazing material is intermittently formed along the periphery of the joining brazing material. It is characterized by being.

  According to the above configuration, since the composite brazing material is intermittently formed along the periphery of the joining brazing material, compared to the case where the composite brazing material is continuously formed, the metal member and the metal member are combined. The freedom degree with respect to the setting position of the joining area | region joined using a joining brazing material can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, when joining a metal member and a metal member with a brazing material, the appropriate thickness of a brazing material is securable.

(A) (B) (C) It is process drawing which showed the joining procedure of the brazing structure which concerns on 1st Embodiment. In the brazing structure which concerns on 1st Embodiment, it is the perspective view which showed the state by which the powder lump and the slurry were apply | coated to the metal plate. (A) (B) (C) It is process drawing which showed the joining procedure of the brazing structure which concerns on the comparative example of the brazing structure which concerns on 1st Embodiment. (A) (B) It is the top view which showed the brazing structure which concerns on 2nd Embodiment.

<First Embodiment>
An example of the brazing structure according to the first embodiment of the present invention will be described with reference to FIGS. In addition, arrow UP shown in the figure shows the upper direction of the perpendicular direction.

(overall structure)
As shown in FIG. 1C, the brazing structure 10 according to the first embodiment used for joining a pair of metal plates 50 (an example of a pair of metal members) is a pair of metal plates 50 facing each other. It is sandwiched between. The brazing structure 10 includes a bonding brazing material 12 that diffuses into each metal plate 50 and forms a bonding interface with the metal plate 50. Further, the brazing structure 10 includes a composite brazing material 16 which is disposed on the periphery of the joining brazing material 12 and which comprises a brazing material of the same kind as the brazing material constituting the joining brazing material 12 and a metal powder. Yes.

  In the present embodiment, a stainless steel plate (SUS steel plate) is used as the metal plate 50.

[Bonding brazing material]
As the bonding brazing material 12, one having a melting point lower than that of the stainless steel metal plate 50 and capable of being eutectic bonded to the metal plate 50 is used. As the joining brazing material 12, a Ni-based (nickel) brazing material, an Fe-based (iron) brazing material, an Ag-based (silver) brazing material, or a Ti-based (titanium) brazing material can be used. In the embodiment, as an example, a Ni-based (nickel) brazing material is used as the joining brazing material 12. That is, the joining brazing material 12 is made of a Ni-based brazing material.

[Composite brazing material]
The composite brazing material 16 is continuously formed along the periphery of the joining brazing material 12. The composite brazing material 16 is a composite material that includes a Ni-based brazing material and metal powder that is a fine powder of stainless steel. Specifically, the composite brazing material 16 is formed by impregnating a metal powder with a Ni-based brazing material and eutectically bonding the Ni-based brazing material to the surface of the metal powder at a brazing temperature.

  Moreover, in this composite brazing material 16, the volume ratio of the Ni-based brazing material to the metal powder is 25% or more and 50% or less.

  Furthermore, the height of the composite brazing material 16 (dimension D shown in FIG. 1C) is equivalent to the height of the joining brazing material 12 (dimension E shown in FIG. 1C) (same in this embodiment). (For example, 80 to 100 [μm]).

(Joining procedure)
The joining procedure for joining the pair of metal plates 50 includes an application step of applying a member to be the joining brazing material 12 and the composite brazing material 16 to one metal plate 50, and one metal plate 50 and the other metal plate 50. And a joining step for joining.

[Coating process]
In the application step, as shown in FIG. 2, the liquid slurry 22 that becomes the bonding brazing material 12 is applied to one metal plate 50 so as to extend in one direction. The slurry 22 is a liquid member in which a Ni-based brazing material and a binder are mixed at a volume ratio of 50%.

  Further, a powder lump 14, which is a lump of stainless steel metal powder, is continuously applied along the periphery of the slurry 22 (applied so as to surround the slurry 22).

  Here, the volume of the Ni-based brazing material contained in the slurry 22 is determined in consideration of the volume constituting the joining brazing material 12 and the volume constituting the composite brazing material 16. As shown in FIG. 1 (A), the height of the slurry 22 (dimension F shown in FIG. 1 (A)) is higher than the height of the powder mass 14 (dimension G shown in FIG. 1 (A)). Has been.

  Further, the maximum particle diameter of the metal powder constituting the powder lump 14 is such that the height of the powder lump 14 is half or less of the width of the powder lump 14 (dimension M shown in FIG. 1A).

[Jointing process]
In the joining step, one metal plate 50 coated with the slurry 22 and the powder lump 14 and the other metal plate 50 are placed in a heating furnace (not shown), and the Ni-based brazing material contained in the slurry 22 is melted. Let The temperature in the heating furnace is set so that the Ni-based brazing material melts but the metal plate 50 does not melt (for example, 180 [° C.]).

  Then, as shown in FIGS. 1B and 1C, the slurry 22 is pressed between the pair of metal plates 50 to join the pair of metal plates 50.

  Specifically, by pressing the slurry 22 with a pair of metal plates 50, a part of the slurry 22 enters between the metal powders constituting the powder lump 14, and further included in the slurry 22 due to heat in the heating furnace. The binder is evaporated. Then, the Ni-type brazing material contained in the slurry 22 is impregnated into the metal powder of the powder lump 14 and the Ni-type brazing material is eutectic bonded to the surface of the metal powder, whereby the composite brazing material 16 is formed ( (See FIG. 1C).

  Further, as the binder evaporates from the slurry 22, the slurry 22 in the region surrounded by the powder mass 14 (composite brazing material 16) becomes the bonding brazing material 12, and the bonding brazing material 12 is bonded to the metal plate 50. It diffuses and eutectic bonds with the metal plate 50. Thus, the pair of metal plates 50 are joined (brazed) by the joining brazing material 12.

  In the state where the pair of metal plates 50 are joined, the height of the composite brazing material 16 (dimension D shown in FIG. 1C) is the height of the joining brazing material 12 (dimension E shown in FIG. 1C). (Same in this embodiment). Further, the height of the composite brazing material 16 is equal to the height of the powder lump 14 (the dimension G shown in FIG. 1A) (same in this embodiment).

  On the other hand, as a comparative form with respect to the present embodiment, FIGS. 3A, 3B, and 3C describe a configuration in which a powder lump is not applied in the application step. In this comparative form, when the slurry is pressed against the pair of metal plates 50, the slurry is crushed and spreads from the bonding interface (designed bonding interface).

  However, in the present embodiment, the powder mass 14 is continuously applied along the periphery of the slurry 22 in the application step, so that the slurry 22 does not spread outside the bonding interface with the metal plate 50. Yes.

(Action / Effect)
Thus, in the application process, the powder lump 14 is continuously applied along the periphery of the slurry 22, so that a part of the slurry 22 infiltrates between the metal powders of the powder lump 14 in the joining process. The Ni-type brazing material contained in the slurry 22 is impregnated into the metal powder of the lump 14, and the Ni-type brazing material is eutectic bonded to the surface of the metal powder. And the slurry 22 is dammed by the powder lump 14 (damming effect). For this reason, compared with the case where the composite brazing material 16 (powder lump 14) is not provided, when joining the metal plate 50 and the metal plate 50 with the joining brazing material 12, the joining brazing material 12 (slurry 22) is formed. It is possible to suppress the flow out of the joint interface with the metal plate 50.

  Further, since the composite brazing material 16 (powder lump 14) is continuously formed along the peripheral edge of the bonding brazing material 12 (slurry 22), it is compared with the case where it is not continuously formed. It is possible to effectively suppress the material 12 (slurry 22) from flowing out of the joint interface with the metal plate 50.

  Further, by suppressing the joining brazing material 12 from flowing out to the outside of the joining interface with the metal plate 50, the slurry 22 becomes a brazing filler metal layer of the joining brazing material 12 within an arbitrary set area (joining interface area). Formed as.

  Further, since the powder lump 14 continuously applied along the periphery of the slurry 22 serves as a support when the pair of metal plates 50 are joined, and exhibits a support effect (spacer effect), the composite brazing material 16 Compared with the case where the powder lump 14 is not provided, the distance between the pair of metal plates 50 can be set to a predetermined distance (a strut effect).

  Moreover, since the space | interval of a pair of metal plate 50 can be made into a predetermined distance, the appropriate thickness of the joining brazing material 12 is securable.

  Further, by optimizing the thickness of the bonding brazing material 12, the composition diffusion of the bonding brazing material 12 at the bonding interface can be sufficiently performed.

  In addition, since the structure diffusion of the brazing filler metal 12 is sufficiently performed, the brazing filler metal strength is reduced due to precipitation of additives (Si, B, Ni, P, etc.) due to compositional segregation inside the bonding brazing filler metal 12 layer. Can be suppressed. This effect is more remarkable in a brazing material having high wettability with respect to the metal plate 50.

  In addition, since the brazing filler metal 12 and the metal plate 50 form a eutectic composition at the bonding interface with the metal plate 50, the anti-segregation force (force to prevent precipitation) with respect to the additive can be improved.

  The height of the composite brazing material 16 is equal to the height of the joining brazing material 12. For this reason, when the slurry 22 is pressed by the pair of metal plates 50 to join the pair of metal plates 50, the eccentricity of the slurry 22 due to the load on the slurry 22 in the pressing direction (vertical direction in the present embodiment), and The amount of lateral deviation of the slurry 22 can be suppressed. That is, the lateral shift amount (shift amount in the direction orthogonal to the pressing direction) of the other metal plate 50 with respect to one metal plate 50 can be suppressed.

  Further, the Ni-type brazing material contained in the slurry 22 is impregnated between the metal powders of the powder lump 14 and the Ni-type brazing material is eutectic bonded to the surface of the metal powder, whereby the composite brazing material 16 is formed. Therefore, the impact value (for example, Izod impact value) of the composite brazing material 16 can be improved.

  Further, since the Ni-type brazing material contained in the slurry 22 is impregnated into the metal powder of the powder lump 14 and the Ni-type brazing material is eutectic bonded to the surface of the metal powder, the composite brazing material 16 is formed. The liquidus temperature of the composite brazing material 16 is improved. Thereby, a healthy and strong bonding interface can be formed.

  In the composite brazing material 16, the volume ratio of the Ni-based brazing material to the metal powder is set to 25% or more and 50% or less. For this reason, it is possible to suppress a decrease in brazing material strength due to precipitation of additives (Si, B, Ni, P, etc.) due to compositional segregation inside the 16 layers of the composite brazing material. Specifically, when it is less than 25%, the eutectic bond between the metal powder and the Ni-based brazing material is insufficient, and when it is more than 50%, additives (Si, B, Ni, P, etc.) ) Will precipitate.

  Further, a stainless steel plate is used as the metal plate 50, and particles obtained by pulverizing stainless steel are used as the metal powder of the powder lump 14. Thus, the metal powder of the powder lump 14 is made of the same metal material as that of the metal plate 50 or a metal material containing at least one composition of the main components of the metal plate 50, so that the metal plate 50 and the joining brazing material 12 A good bonding layer can be formed at the interface between the metal powder surface of the powder lump 14 and the Ni-based brazing material.

  In addition, the maximum particle diameter of the metal powder of the powder lump 14 is not more than half the height of the powder lump 14 and the width of the powder lump 14. For this reason, the height of the powder lump 14 applied to the metal plate 50 and the width of the powder lump 14 can be within a predetermined range.

<Second Embodiment>
Next, an example of the brazing structure according to the second embodiment of the present invention will be described with reference to FIGS. In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. Moreover, only a different part from 1st Embodiment is demonstrated and description of another part is abbreviate | omitted.

  As shown in FIG. 4B, in the brazing structure 30 according to the second embodiment, a plurality of composite brazing materials 32 are intermittently formed along the periphery of the joining brazing material 12. 4B, the brazing structure 30 is shown in plan view, but the other metal plate 50 (the metal plate mounted from above) is shown so that the configuration of the brazing structure 30 can be easily understood. 50) is omitted.

  The composite brazing material 32 is applied in the form of dots, and the distance between adjacent composite brazing materials 32 (dimension H shown in FIG. 4B) is the height of the composite brazing material 32 (dimensions shown in FIG. 1C). D) is 100 times or less. For example, when the height of the composite brazing material 32 is 100 [μm], the distance between the adjacent composite brazing materials 32 (dimension H shown in FIG. 4B) is 10 [mm] or less, preferably Is 5 mm or less (50 times the height or less).

[Coating process]
In the application step, as shown in FIG. 4A, the slurry 22 is applied to the metal plate 50 so as to extend in one direction. Further, a plurality of powder masses 34 are intermittently applied along the periphery of the slurry 22. In this case, the distance between adjacent powder masses 34 (dimension J shown in FIG. 4A) is 100 times or less the height of the powder mass 34 (dimension G shown in FIG. 1A). ing. The distance (dimension J) between adjacent powder masses 34 is equivalent to the distance (dimension H) between the adjacent composite brazing materials 32 described above.

[Jointing process]
In the joining step, one metal plate 50 coated with the slurry 22 and the powder lump 34 and the other metal plate (not shown) are placed in a heating furnace (not shown), and the Ni brazing material contained in the slurry 22 is placed. Melt. The temperature in the heating furnace is set so that the Ni-based brazing material melts but the metal plate 50 does not melt. The slurry 22 is pressed by the pair of metal plates 50 to join the pair of metal plates 50.

  Specifically, by pressing the slurry 22 with a pair of metal plates 50, a part of the slurry 22 enters between the metal powders of the powder lump 34, and the binder contained in the slurry 22 by the heat in the heating furnace. Evaporates.

  Here, the brazing material that flows out from between the adjacent powder masses 34 to the outside of the joining interface with the metal plate 50 (the brazing material generated by the evaporation of the binder from the slurry 22 that has entered the powder mass 34) has a powder on both sides. A force is drawn into the mass 34 by capillary action. Thereby, the component of the brazing material in this portion (range K shown in FIG. 4B) is denatured, and the brazing material in this portion is thickened and hardened quickly. In this way, the flow resistance between the adjacent powder masses 34 (composite brazing material 32) increases due to the capillary force and the increase in the viscosity of the brazing material. It is suppressed that it tries to flow out of the outside.

  Thus, in the application process, the powder mass 34 is intermittently applied along the periphery of the slurry 22, so that the slurry 22 flows out from between the adjacent powder masses 34 to the outside of the bonding interface with the metal plate 50. Can be suppressed.

  In addition, since the plurality of powder lumps 34 are applied intermittently, the amount of the slurry 22 sucked into the powder lump 34 is reduced as compared with the case where the powder lump is continuously applied along the periphery of the slurry. Therefore, for example, even when the application width of the slurry 22 is narrow (particularly 1 [mm] or less), the pair of metal plates 50 can be satisfactorily bonded.

  In addition, since the plurality of powder lumps 34 are intermittently applied, the metal plate 50 and the metal plate 50 are joined to the brazing filler metal 12 as compared with the case where the powder lump is continuously applied along the periphery of the slurry. The degree of freedom with respect to the set position of the joining region to be joined can be improved.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments can be taken within the scope of the present invention. This will be apparent to those skilled in the art. For example, in the above embodiment, in the joining step, the Ni-based brazing material contained in the slurry is melted using a heating furnace, but the Ni-based brazing material may be melted using high-frequency induction heating or the like.

  Moreover, in the said embodiment, although the height of the composite brazing materials 16 and 32 and the height of the joining brazing material 12 were made equivalent, you may make the height of a joining brazing material higher than the height of a composite brazing material, What is necessary is just to be able to suppress the slurry 22 from flowing outside the bonding interface with the metal plate 50.

  In the first embodiment, the composite brazing material 16 is continuously formed along the peripheral edge of the joining brazing material 12. However, the composite brazing material is discontinuously formed so as to be partially cut, for example. It suffices if the slurry 22 can be prevented from flowing out of the joining interface with the metal plate 50.

  Further, although not specifically described in the above embodiment, the application of the slurry and the powder lump to the metal plate in the application process may be performed using screen printing or the like.

  Moreover, although not specifically described in the above embodiment, the order of the application of the slurry to the metal plate and the application of the powder lump to the metal plate in the application step may be either first or simultaneously. Good.

  Although not specifically described in the second embodiment, the dot-shaped composite brazing material 32 may be circular, rectangular, or the like.

  Moreover, in the said embodiment, although the stainless steel plate was used as a metal plate and Ni-type brazing material was used as a brazing material, stainless steel was used as a metal plate, Fe-type brazing material, Ag-type brazing material, Ti-type brazing material Etc. may be used.

  In the above embodiment, stainless steel is used as the metal plate and Ni-based brazing material is used as the brazing material. However, a copper plate is used as the metal plate, a Cu-based brazing material is used as the brazing material, and aluminum is used as the metal plate. A plate may be used, and an Al-based brazing material may be used as the brazing material.

DESCRIPTION OF SYMBOLS 10 Brazing structure 12 Joining brazing material 14 Powder lump 16 Composite brazing material 22 Slurry 30 Brazing structure 32 Composite brazing material 34 Powder lump 50 Metal plate

Claims (8)

A brazing filler metal sandwiched between a pair of opposing metal members and diffused and joined to each of the metal members;
A composite brazing material sandwiched between a pair of the metal members, disposed on the periphery of the joining brazing material, and comprising a brazing material of the same type as the brazing material constituting the joining brazing material and a metal powder;
Brazing structure with.   The brazing structure according to claim 1, wherein the composite brazing material is impregnated with a brazing material of the same type as the brazing material constituting the joining brazing material.   The brazing structure according to claim 1, wherein the composite brazing material has a brazing material of the same type as the brazing material constituting the joining brazing material eutectic bonded to the surface of the metal powder.   The volume ratio of the brazing material of the same kind as the brazing material constituting the joining brazing material to the metal powder in the composite brazing material is 25% or more and 50% or less. The brazed structure described.   The brazing structure according to any one of claims 1 to 4, wherein a height of the composite brazing material is equal to a height of the joining brazing material.   The brazing structure according to any one of claims 1 to 5, wherein the composite brazing material is continuously formed along a peripheral edge of the joining brazing material.   The brazing structure according to any one of claims 1 to 5, wherein the composite brazing material is formed discontinuously along a peripheral edge of the joining brazing material.   The brazing structure according to any one of claims 1 to 5, wherein the composite brazing material is intermittently formed along a periphery of the joining brazing material.

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