WO2019167454A1

WO2019167454A1 - Joint structural body and method for manufacturing same

Info

Publication number: WO2019167454A1
Application number: PCT/JP2019/001057
Authority: WO
Inventors: 将也中村; 白井　秀彰; 河西　文男
Original assignee: 株式会社デンソー
Priority date: 2018-02-28
Filing date: 2019-01-16
Publication date: 2019-09-06
Also published as: JP2019147184A

Abstract

A joint structural body (1) has a first metal base material (11) which is configured from first metal, a second metal base material (12) which is configured from second metal, and a weld metal section (13) which connects the first metal base material (11) and the second metal base material (12). The weld metal section (13) is configured from an alloy of the first metal, the second metal, and third metal which has a melting point lower than those of the first metal and the second metal. The first metal base material (11) and the second metal base material (12) are connected only through the weld metal section (13). A weld material (2) configured from the third metal, the melting point of which is lower than those of the first metal and the second metal, is directly locally heated to melt the weld material (2) and also to melt part of each of the first metal and the second metal, thereby forming a molten section (5) containing the third metal, the first metal, and the second metal. Then the heating is stopped to allow the molten section (5) to solidify to thereby form the weld metal section (13), which connects the first metal base material (11) and the second metal base material (12).

Description

Junction structure and manufacturing method thereof

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2018-34806 filed on February 28, 2018, the contents of which are incorporated herein by reference.

The present disclosure relates to a bonded structure and a manufacturing method thereof.

Conventionally, Patent Document 1 includes a conductor having a joining portion and a joining member having a melting point lower than that of the conductor, and a tip portion of the joining portion forms an alloy layer made of an alloy of the conductor and the joining member. A joint structure in which the base part of the joint is electrically joined by brazing of a joining member is described. Further, this document describes that the joining member and the conductor are melted by a gas arc to obtain the above joined structure.

WO2016 / 103989

The conventional technology described above is a technology for forming both an alloy layer and a brazing layer. According to this prior art, it is necessary to sandwich a brazing material for forming a brazing layer between metal base materials to be joined to each other. Therefore, the conventional joint structure has a problem that it is difficult to realize a reduction in size and weight because the brazing layer is included in addition to the alloy layer.

This disclosure is intended to provide a joint structure that can be reduced in size and weight as compared with the conventional one, and a manufacturing method thereof.

One aspect of the present disclosure includes a first metal base material made of a first metal, a second metal base material made of a second metal, the first metal base material, and the second metal base material. A welded metal part to be connected,
The weld metal part is composed of an alloy of the first metal, the second metal, the first metal, and a third metal having a melting point lower than that of the second metal,
The first metal base material and the second metal base material are in a joint structure that is connected only through the weld metal portion.

In another aspect of the present disclosure, the first metal and the second metal are disposed between a first metal base composed of a first metal and a second metal base composed of a second metal. Direct heat input locally to the welding material composed of a third metal having a lower melting point,
A melting part containing the third metal, the first metal, and the second metal by melting the welding material by heating by the heat input and further melting a part of the first metal and the second metal. Form the
In the method for manufacturing a joined structure, the heat input is stopped to solidify the molten portion, and a weld metal portion is formed to connect the first metal base material and the second metal base material.

The joint structure has the above configuration. In particular, the first metal base material and the second metal base material are connected only through the weld metal part, and the weld metal part includes the first metal, the second metal, the first metal, and the second metal. It is composed of an alloy with a third metal having a lower melting point. According to the above bonded structure, it is not necessary to sandwich a brazing material for forming a brazing layer between the first metal base material and the second metal base material during welding. In addition, the joint structure is not a structure having both an alloy layer and a brazing layer as in the conventional joint structure, but only the weld metal portion, and the first metal base material and the second metal base material are It is integrated. Therefore, according to the above-mentioned joined structure, space saving can be achieved as much as the brazing layer can be omitted, and a reduction in size and weight can be realized. Moreover, since the said joining structure is hard to receive the heat influence from a brazing part, there also exists an advantage which is easy to ensure intensity | strength.

The manufacturing method of the joined structure has the above configuration. Therefore, in the manufacturing method of the joined structure, the heat conduction to the first metal base material and the second metal base material is hindered by directly applying heat locally to the low melting point welding material, and the temperature rise Speed can be accelerated. When the melting point of the third metal, which is lower than the melting points of the first metal and the second metal, is reached by heating due to heat input, melting of the welding material starts. When the melting point of the first metal of the first metal base material and the second metal of the second metal base material reach the melting points of the first metal base material, the first metal and the second metal start to melt. As a result, a molten part including the third metal, the first metal, and the second metal is formed. Then, the said heat input is stopped | fastened and the molten part is solidified, and the weld metal part which connects a 1st metal base material and a 2nd metal base material is formed.

According to the method for manufacturing a bonded structure, the bonded structure can be manufactured in a relatively small amount of total heat input and in a short time.

In addition, the code | symbol in the parenthesis described in the claim shows the correspondence with the specific means as described in embodiment mentioned later, and does not limit the technical scope of this indication.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. The drawing
FIG. 1 is a plan view schematically showing a bonded structure according to Embodiment 1. 2 is a cross-sectional view schematically showing a cross section taken along line II-II in FIG. FIG. 3 is an explanatory diagram for explaining a method for measuring the content of alloy elements in the body portion at each welding depth position and the Vickers hardness, FIG. 4 is an explanatory diagram for explaining a manufacturing method of the bonded structure according to the second embodiment. FIG. 5 is an explanatory diagram for explaining a modification of the groove portion shown in FIG. FIG. 6 is an explanatory diagram for schematically explaining the operational effects of the manufacturing method of the bonded structure according to the second embodiment. FIG. 7 is an explanatory diagram for explaining a method of manufacturing the bonded structure of the sample 1 in Experimental Example 1. FIG. 8 is a photograph of the joined structure of Sample 1 in Experimental Example 1 as viewed from above. FIG. 9 is a photograph showing a longitudinal section of the bonded structure of Sample 1 in Experimental Example 1, FIG. 10 is a photograph showing a longitudinal section of the bonded structure of Sample 2 in Experimental Example 2, FIG. 11 is a Vickers hardness distribution of the bonded structure of Sample 2 in Experimental Example 2.

(Embodiment 1)
The bonded structure of Embodiment 1 will be described with reference to FIGS. 1 and 2. As illustrated in FIG. 1 and FIG. 2, the joint structure 1 of the present embodiment includes a first metal base material 11, a second metal base material 12, and a weld metal portion 13. This will be described in detail below.

The first metal base material 11 is composed of a first metal. Specific examples of the first metal include copper, aluminum, iron, and alloys thereof. Similarly, the second metal base material 12 is made of a second metal. Specific examples of the second metal include copper, aluminum, iron, and alloys thereof.

The first metal and the second metal are preferably selected so that their melting points, characteristics, and the like are similar to each other from the viewpoints of the strength and conductivity of the bonded structure 1. Specifically, in the bonded structure 1, the first metal and the second metal are preferably the same type of metal. According to this configuration, it is possible to obtain the joint structure 1 that easily secures necessary strength and conductivity while reducing the size and weight. In addition, the same kind means the case where the metal components with the highest content are the same when the chemical composition (mass%) of the first metal and the second metal is viewed. In the present embodiment, from the viewpoint of the strength and conductivity of the bonded structure, both the first metal and the second metal can be copper or a copper alloy.

The weld metal part 13 is a part that connects the first metal base material 11 and the second metal base material 12. The weld metal portion 13 is a metal portion that has been melted and solidified during welding, and does not include a heat affected zone. The first metal base material 11 and the second metal base material 12 are connected only through the weld metal part 13. That is, the 1st metal base material 11 and the 2nd metal base material 12 do not have a brazing layer like the prior art mentioned above, and are joined only by the weld metal part 13. FIG.

The weld metal portion 13 is composed of an alloy of a first metal, a second metal, and a third metal. The first metal is a metal derived from the first metal base material 11, and the second metal is a metal derived from the second metal base material 12. The third metal is a metal having a lower melting point than the first metal and the second metal.

When the first metal and the second metal are, for example, copper or a copper alloy, specifically, examples of the third metal include a copper alloy having a melting point lower than these. In this case, as the third metal, more specifically, P or a copper alloy containing P and Ag can be exemplified. As a copper alloy containing P or P and Ag, P: 4.8 to 5.3% by mass, the balance being Cu and inevitable impurities (Pb, Sn, Fe: 0.2% or less in total) ) Copper alloy (BCuP-1 as defined in JIS Z3264), mass%, P: 6.8 to 7.5%, the balance being Cu and inevitable impurities (Pb, Sn, Fe: 0.2 in total) % Copper alloy (BCuP-2 specified in JIS Z3264), P: 5.8 to 6.7% by mass, Ag: 4.8 to 5.2%, the balance being Cu and inevitable Copper alloy (BCuP-3 as defined in JIS Z3264) composed of impurities (Pb, Sn, Fe: 0.2% or less in total), mass%, P: 6.8 to 7.7%, Ag: 5 8 to 6.2%, the balance being Cu and inevitable impurities (Pb, Sn, Fe: total 0.2% or less) copper alloy (BCuP-4 as defined in JIS Z3264), P: 4.8 to 5.3%, Ag: 14.5 to 15.5%, balance in mass% Is a copper alloy (BCuP-5 as defined in JIS Z3264) composed of Cu and inevitable impurities (Pb, Sn, Fe: 0.2% or less in total), P: 6.8 to 5.3% in mass% , Ag: 1.8 to 2.2%, the balance being Cu and copper alloy (Pb, Sn, Fe: 0.2% or less in total) (CuCu-6 defined in JIS Z3264), etc. It can be illustrated.

For example, when the first metal and the second metal are both aluminum or an aluminum alloy, specific examples of the third metal include an aluminum alloy having a melting point lower than these. In this case, as the third metal, more specifically, various types of aluminum alloy solders defined in JIS Z3263: 2002 can be exemplified.

When both the first metal and the second metal are, for example, iron or an iron alloy, specifically, as the third metal, a copper-based alloy, an iron-based alloy, a Ni-based metal, or the like having a lower melting point than these. Can be illustrated.

The joint structure 1 of the present embodiment has the above configuration. In particular, the first metal base material 11 and the second metal base material 12 are connected only through the weld metal part 13, and the weld metal part 13 includes the first metal, the second metal, and the first metal. And an alloy of a third metal having a melting point lower than that of the second metal. According to the joint structure 1 of the present embodiment, it is not necessary to sandwich a brazing material for forming a brazing layer between the first metal base material 11 and the second metal base material 12 during welding. Moreover, the joining structure 1 of this embodiment is not a structure having both an alloy layer and a brazing layer as in the conventional joining structure, but only the weld metal portion 13 and the first metal base material 11 and the first metal base material 11. The two-metal base material 12 is integrated. Therefore, according to the joint structure 1 of the present embodiment, the space can be saved as much as the brazing layer can be omitted, and a reduction in size and weight can be realized. Moreover, since the joining structure 1 of this embodiment is hard to receive the heat influence from a brazing part, there also exists an advantage which is easy to ensure intensity | strength.

In the joined structure 1, the weld metal portion 13 includes a head 131 that is raised to a height that is higher than the surface of both base metals of the first metal base material 11 and the second metal base material 12, as illustrated in FIG. 2. The body part 132 extending in the welding depth direction from the bottom surface of the head part 131 can be used. According to this configuration, the first metal base material 11 and the second metal base material 12 are integrated with each other while the strength is secured only by the weld metal portion 13 without forming a brazing layer as in the above-described prior art. Can be Therefore, according to the said structure, the joining structure 1 which is easy to obtain the effect mentioned above is obtained. Moreover, since the weld metal part 13 swells more than the surface of both base materials, since there is no undercut and the stress concentration part which acts on the weld metal part 13 decreases, it is possible to improve the durability of the joint structure 1. become.

As illustrated in FIG. 2, specifically, the weld metal portion 13 can be in a state in which the side surface of the first metal base material 11 and the side surface of the second metal base material 12 are in contact with each other. . The first metal base material 11 and the second metal base material 12 can be arranged such that the surfaces of the base materials are substantially flush. The positions of both the base metal surfaces of the first metal base material 11 and the second metal base material 12 are defined as a reference plane BP, and the head is located on the outer side of the first metal base material 11 and the second metal base material 12 from the reference plane BP. The height direction of 131 is taken. Further, the welding depth direction is taken from the reference plane BP to the inside of the first metal base material 11 and the second metal base material 12. In this case, from the viewpoint of improving the strength of the bonded structure 1 and the like, the height H of the head 131 of the weld metal part 13 is preferably 0 or more, more preferably 0, on the entire surface of the weld metal part 13. It should be super. In FIG. 2, the case where the height H of the head 131 is the highest is shown as an example.

As illustrated in FIG. 2, the body portion 132 of the weld metal portion 13 can be formed such that the tip is tapered in the weld depth direction in a cross-sectional view along the weld depth direction. Further, the width at the base end of the body portion 132 is W1, the depth from the base end to the tip end of the body portion 132 is D, and the body portion 132 is configured to satisfy the relationship of D / W1 ≧ 1. it can. According to this configuration, it is easy to ensure the bonding strength between the first metal base material 11 and the second metal base material 12. Moreover, the stress which acts at the time of solidification and contraction can be reduced, and there is an advantage that the reliability of the weld metal part 13 is improved. D / W1 can be preferably more than 1, more preferably 1.2 or more.

Further, when the width of the head 131 is W2, the body 132 can be configured to satisfy the relationship of W1 ≦ W2. According to this configuration, since the bottom surface of the head 131 is in contact with the outer surfaces of the first metal base material 11 and the second metal base material 12, the height H of the head 131 of the weld metal part 13 is 0 or more. This makes it easier to improve the strength of the bonded structure 1.

It is preferable that the alloy component of the weld metal portion 13 is uniformized when viewed in the weld depth direction. According to this configuration, the weld metal portion 13 is formed by uniform melting and solidification of dissimilar metals having different melting points, thereby suppressing defects (distortion, cracking, thermal influence, etc.) caused by melting. The body 1 can be obtained.

Here, as illustrated in FIG. 3, in the welding depth direction, the alloy element of the trunk portion 132 at the center position in the welding width direction at each welding depth position of the trunk portion 132 is measured. In this case, first, the measurement object can be an element that is not contained in the first metal and the second metal but is contained only in the third metal. If there is no such element, among the alloy elements constituting the weld metal part 13, an element having a higher content (mass%) than the first metal and the second metal may be measured. it can. In the measurement, the measurement area at each welding depth position is a rectangular area of 0.1 mm × 0.1 mm. Further, the measurement is performed until the first metal base material 11 and the second metal base material 12 outside the trunk portion 132 are included at a pitch of 0.2 mm from the reference surface BP and the reference surface BP. The content (%) of the element to be measured at each welding depth position from the reference plane BP side is A1 (reference plane BP), A2, A3,. However, An is the content (mass%) of the last element to be measured in the body portion 132 just before the body portion 132 that goes out of the body portion 132. When the average value from A1 to An is A _ave , the content (mass%) of the alloy element in the body portion 132 at each welding depth position is preferably 0.6 × A _ave or more and 1.4 or more. × A _ave or less, more preferably 0.7 × A _ave or more and 1.3 × A _ave or less, and further preferably 0.8 × A _ave or more and 1.2 × A _ave or less. According to this configuration, the alloy components in the weld metal portion 13 can be made uniform.

Similarly to the measurement of the alloy element of the trunk portion, the Vickers hardness of the trunk portion 132 at the center position in the welding width direction at each welding depth position of the trunk portion 132 is measured in the welding depth direction. In the measurement, the measurement area at each welding depth position is a rectangular area of 0.1 mm × 0.1 mm. Further, the measurement is performed until the first metal base material 11 and the second metal base material 12 outside the trunk portion 132 are included at a pitch of 0.2 mm from the reference surface BP and the reference surface BP. Vickers hardness (Hv) at each welding depth position from the reference surface BP side is set to B1 (reference surface BP), B2, B3,. However, Bn is the last Vickers hardness in the body part 132 just before the body part 132 that goes out of the body part 132. When the average value from B1 to Bn is B _ave , the Vickers hardness (Hv) of the body portion 132 at each welding depth position is preferably 0.6 × B _ave or more and 1.4 × B _ave Hereinafter, more preferably 0.7 × B _{ave to} 1.3 × B _ave , and still more preferably 0.8 × B _{ave to} 1.2 × B _ave . According to this configuration, the alloy components in the weld metal portion 13 can be made uniform.

In the bonded structure 1, each of the first metal base material 11 and the second metal base material 12 has an insulating coating 14 on the surface of the base material as illustrated in FIG. 1. The first metal base material 11 and the second metal base material 12 exposed by peeling off can be configured to be connected only through the weld metal portion 13. According to this configuration, it is possible to shorten the peeling length of the insulating coating 14 as compared with the conventional bonding structure having both the alloy layer and the brazing layer, and to reduce the space and size of the bonding structure 1. It is advantageous to make.

Specific examples of the use of the bonded structure 1 include a bonded portion that requires conduction in a generator or the like, and a bonded portion of a structural member that requires strength and airtightness. More specifically, the junction structure 1 can be used, for example, in a stator winding of a rotating electrical machine to form a junction between adjacent conductors. In this case, it is advantageous for reducing the size and weight of the rotating electrical machine by reducing the size and weight of the joint structure 1.

(Embodiment 2)
A method for manufacturing the bonded structure according to the second embodiment will be described with reference to FIGS. Of the reference numerals used in the second and subsequent embodiments, the same reference numerals as those used in the above-described embodiments represent the same components as those in the above-described embodiments unless otherwise indicated. The description of the bonded structure of Embodiment 1 can be referred to as appropriate.

In the method for manufacturing a bonded structure according to the present embodiment, as illustrated in FIG. 4A, a first metal base material 11 made of a first metal and a second metal base material made of a second metal. The direct heat input is performed locally on the welding material 2 disposed between the two.

The welding material 2 is composed of a third metal having a melting point lower than that of the first metal and the second metal. For example, the welding material 2 may be supplied in the form of a wire or the like, or may be supplied in the form of a powder or the like.

Specifically, the welding material 2 can be disposed in a groove portion 3 formed of a groove provided between the first metal base material 11 and the second metal base material 12. According to this structure, it becomes possible to supply the welding material 2 to the groove part 3, and it becomes easy to implement uniform melting in the welding depth direction. In FIG. 4, specifically, the first metal base material 11 and the second metal base material 12 in a state where the side surface of the first metal base material 11 and the side surface of the second metal base material 12 are in contact with each other. An example in which the groove portion 3 is provided between them is shown. In FIG. 4A, a V-shaped groove portion 31 is illustrated as the groove portion 3. In addition to this, the groove portion includes a re-shaped groove portion 32 illustrated in FIG. 5A, a J-shaped groove portion illustrated in FIG. 5B, and H illustrated in FIG. It may be a groove portion or the like. The cross-sectional shape of the groove portion 3 can be appropriately selected from those defined in JIS Z3001-1: 2013.

It is preferable to use laser light 4 for heat input to the welding material 2. According to this configuration, it is easier to selectively heat the welding material 2 than in the case of using plasma or the like. Therefore, heat conduction to the first metal base material 11 and the second metal base material 12 is likely to be hindered, and the temperature increase rate is easily accelerated. Furthermore, since the absorption efficiency of the laser beam 4 is improved as the welding material 2 is melted, it becomes easier to accelerate the heating rate. Therefore, according to this configuration, it becomes easier to shorten the manufacturing time of the bonded structure 1. Moreover, according to this structure, since it becomes easy to input heat directly into the welding material 2, it becomes easy to obtain the joining structure 1 with few welding defects, such as a thermal influence and a crack. 5A to 5C show an example in which the laser beam 4 is used for heat input to the welding material 2.

In the manufacturing method of the bonded structure according to the present embodiment, as illustrated in FIGS. 4B and 4C, the welding material 2 is melted by the heating by the heat input, and the first metal and the first metal By melting a part of the two metals, the melting part 5 including the third metal, the first metal, and the second metal is formed.

Here, when the first metal and the second metal are melted, it is preferable to cause a reducing action to act on the surfaces of the first metal base material 11 and the second metal base material 12. According to this configuration, the surfaces of the first metal base material 11 and the second metal base material 12 (specifically, in the present embodiment, the first metal base material 11 and the second metal base material 12 in the groove portion 3). It is possible to melt the first metal and the second metal while removing the oxide layer that can be formed on the surface of the first metal. Therefore, according to this structure, it becomes easy to obtain the joining structure 1 with few welding defects, such as a thermal influence and a crack.

Specifically, for example, the method of making the reducing action acts is a method in which the welding material 2 is composed of a third metal containing an element that reduces the first metal surface and the second metal surface, the first metal surface, and the first metal surface. And a method of supplying a flux capable of reducing the surface of the two metals from the outside. According to the former method, compared with the latter method, there exists an advantage which can manufacture a joining structure body by simple equipment structure. When the first metal and the second metal are both copper or a copper alloy and the third metal is P or a copper alloy containing P and Ag, Cu can be reduced by P.

In the method for manufacturing a bonded structure according to the present embodiment, as illustrated in FIG. 4D, the first metal base material 11 and the second metal base material are solidified by stopping the heat input and solidifying the melting portion 5. A weld metal part 13 connecting the material 12 is formed. Solidification of the melting part 5 may be either natural cooling or forced cooling.

Next, the operation and effect of the method for manufacturing the bonded structure according to this embodiment will be described with reference to FIG.

In FIG. 6 (a), the line CL represents the time for the manufacturing method in which the first metal base material and the second metal base material are directly heated and welded without using the welding material composed of the third metal. The relationship with the junction temperature is schematically shown. On the other hand, the line of the symbol L schematically shows the relationship between time and the junction temperature in the method for manufacturing the junction structure according to this embodiment. Here, for simplification of the description, the first metal and the second metal are composed of the same material, the first metal and second metal melting is assumed to be the same T _m. In the present embodiment, the laser beam 4 is used as the heat source.

As shown in FIG. 6A, in the manufacturing method of the joint structure according to the present embodiment, the first metal base material 11 and the first metal base material 11 and the first Heat conduction to the two-metal base material 12 is hindered, and the rate of temperature rise can be accelerated (symbol L1). When the melting point _Tm3 of the third metal, which is lower than the melting points of the first metal and the second metal, is reached by heating due to heat input, the welding material 2 starts to melt. As the welding material 2 is melted, the absorption efficiency of the laser beam 4 is improved, and the heating rate can be further accelerated (reference L2). The heating by the heat input, and reaches the first metal and the melting point T _m of a second metal of the second metal base member 12 of the first base metal 11, further melting of the first metal and the second metal begins. As a result, the molten portion 5 including the third metal, the first metal, and the second metal is formed. Then, the said heat input is stopped (code | symbol L3) and the weld metal part 13 which connects the 1st metal base material 11 and the 2nd metal base material 12 is formed by solidifying the fusion | melting part 5 (code | symbol L4).

According to the manufacturing method of the joined structure of the present embodiment, as shown in FIG. 6B, the first metal base material 11 and the second metal base material are used without using the welding material 2 made of the third metal. Compared to the manufacturing method in which heat is directly applied to the material 12 and welding is performed, the joined structure 1 can be manufactured in a relatively short total heat input (total heat input E1 <total heat input E2) and in a short time.

(Experimental example)
<Experimental example 1>
Two rectangular conductor wires 10 covered with the insulating coating 14 were prepared. The base material constituting the conductor wire 10 is oxygen-free copper (C1020). Next, the insulating coatings 14 at the end portions of the two conductor wires 10 were peeled off. Next, when the side surfaces of the conductor wires 10 are brought into contact with each other as shown in FIG. 7A, each conductor is formed such that the V-shaped groove portion 31 shown in FIG. Line 10 was grooved. The width w of the V-shaped groove 31 was 0.8 mm, and the depth d of the V-shaped groove 31 was 0.8 mm. Next, as shown in FIG. 7A and FIG. 7B, the welding material 2 was disposed on the V-shaped groove portion 31 provided between the two conductor wires 10. As the welding material 2, a BCuP-2 material formed in a substantially cylindrical shape having a diameter of 1.2 mm and a length of 2.5 mm was used. Next, as shown in FIG. 7A and FIG. 7B, the welding material 2 was irradiated with the laser beam 4 and heat was input. At this time, the scanning trajectory 40 of the laser beam 4 was as indicated by the arrow shown in FIG. The scanning trajectory 40 of the laser beam 4 is not limited to that shown in FIG. 7A, and can be changed to a scanning trajectory such as a straight line, an arc, or a rectangle. The irradiation conditions of the laser beam 4 were as follows: frequency: 100 Hz, wobbling diameter: 0.5 mm, irradiation length s: 3 mm, scanning feed rate: 40 mm / s, and laser output P: 2 kW (peak). The laser output P was specifically as shown in FIG. And while melting the welding material 2 by the heating by the said heat input, after melt | dissolving a part of base material of both the conductor wires 10 and forming the fusion | melting part 5, heat input is stopped and the fusion | melting part 5 is solidified. It was. As a result, the joined structure 1 of the sample 1 was obtained in which the base materials of the two conductor wires 10 were integrally connected only through the weld metal portion 13 made of an alloy of oxygen-free copper and BCuP-2.

As shown in FIG. 8 and FIG. 9, in the joint structure 1 of the sample 1, the weld metal portion 13 includes a head 131 that is raised to a height higher than the surface of the base material constituting the conductor wire 10, and a head 131. It can be seen that the body portion 132 extends in the welding depth direction from the bottom surface. Further, as shown in FIG. 9, in a cross-sectional view along the welding depth direction, the width at the proximal end of the trunk portion 132 is W1, and the depth from the proximal end to the distal end of the trunk portion 132 is D. It can be seen that the part 132 satisfies the relationship of D / W1 ≧ 1. Further, when the width of the head 131 is set to W2, it can also be seen that the head 131 and the trunk 132 satisfy the relationship of W1 ≦ W2.

<Experimental example 2>
In the method for manufacturing the bonded structure of sample 1 in Experimental Example 1, the bonded structure of sample 2 is the same as the method for manufacturing the bonded structure of sample 1 except that the laser output P is 1.8 kW (peak). The body was made.

With respect to the weld metal portion 13 of the joint structure 1 of the sample 2 shown in FIG. 10, the surface of the base material that is flush with the adjacent conductor wires 10 is defined as a reference plane BP (welding depth 0), and the body of the weld metal portion 13 is shown. The Vickers hardness in the welding depth direction of the part 132 was measured. The result is shown in FIG. According to FIG. 11, since the Vickers hardness (Hv) of the trunk portion at each welding depth position satisfies 0.8 × B _ave or more and 1.2 × B _ave or less, the alloy components are made uniform. Can be determined.

The present disclosure is not limited to the above embodiments and experimental examples, and various modifications can be made without departing from the scope of the disclosure. Moreover, each structure shown by each embodiment and each experiment example can be combined arbitrarily, respectively. That is, although the present disclosure has been described based on the embodiment, it is understood that the present disclosure is not limited to the embodiment, the structure, and the like. The present disclosure includes various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including only one element, more or less, are within the scope and spirit of the present disclosure.

Claims

The first metal base material (11) composed of the first metal, the second metal base material (12) composed of the second metal, and the first metal base material and the second metal base material are connected. A weld metal part (13),
The weld metal part is composed of an alloy of the first metal, the second metal, the first metal, and a third metal having a melting point lower than that of the second metal,
The said 1st metal base material and the said 2nd metal base material are the joining structures (1) connected only through the said weld metal part.
The weld metal part extends in a welding depth direction from a head (131) raised to a height equal to or higher than the surfaces of both the first metal base and the second metal base, and from the bottom of the head. The joint structure according to claim 1, further comprising a trunk portion (132).
In a cross-sectional view along the weld depth direction, the width at the base end of the body portion is W1, and the depth from the base end to the tip end of the body portion is D, where the body portion is D / W1 ≧ 1. The joined structure according to claim 2, satisfying the relationship:
The joint structure according to claim 3, wherein the width of the head is W2, and the head and the body satisfy a relationship of W1 ≦ W2.
The bonded structure according to any one of claims 1 to 4, wherein the first metal and the second metal are the same kind of metal.
The bonded structure according to any one of claims 1 to 5, wherein the weld metal portion has a uniform alloy composition when viewed in the weld depth direction.
Each of the first metal base material and the second metal base material has an insulating coating (14) on the surface of the base material.
The first metal base material and the second metal base material exposed by peeling off each of the insulating coatings are connected only through the weld metal portion. Bonding structure.
Melting | fusing point from the said 1st metal and said 2nd metal arrange | positioned between the 1st metal base material (11) comprised from a 1st metal, and the 2nd metal base material (12) comprised from a 2nd metal Direct heat input to the welding material (2) composed of the third metal having a low
A melting part containing the third metal, the first metal, and the second metal by melting the welding material by heating by the heat input and further melting a part of the first metal and the second metal. Forming (5),
The method for manufacturing a joined structure, wherein the heat input is stopped to solidify the melted portion, and a weld metal portion (13) that connects the first metal base material and the second metal base material is formed.
The said welding material manufactures the junction structure of Claim 8 arrange | positioned at the groove part (3) which consists of a groove | channel provided between the said 1st metal base material and the said 2nd metal base material. Method.
The joint structure manufacturing method according to claim 8 or 9, wherein when the first metal and the second metal are melted, a reducing action is applied to the surfaces of the first metal base material and the second metal base material. Method.