Method for manufacturing electrically conductive components and electrically conductive components

Abstract

To provide a method for manufacturing an electrically conductive component and an electrically conductive component that can reduce the thickness of the joint when forming a joint between a metal foil material and a metal plate material using friction stir point welding. [Solution] The present invention provides a method for manufacturing an electrical component, comprising: a first step of butting together the end face of a plate-shaped metal foil material, which is formed by laminating multiple metal foils, with the end face of a metal sheet material, the thickness of which in the lamination direction of the multiple metal foils is approximately the same as that of the metal foil material; and a second step of friction stirring point bonding the metal foil material and the metal sheet material by rotating a friction stirring bonding tool and inserting it into the metal foil material and the metal sheet material so as to include a portion of the boundary between the butted end faces of the metal foil material and the end faces of the metal sheet material.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a current-carrying component and a current-carrying component.

Background Art

[0002] Conventionally, friction stir spot welding is well known as a spot welding method utilizing the friction stir phenomenon. Patent Document 1 discloses a technique in which an end portion of a metal foil material and an end portion of a metal plate material are overlapped with each other in the thickness direction and subjected to friction stir spot welding.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, for current-carrying components such as bus bars that electrically connect a plurality of battery cases mounted on an electric vehicle, a method of overlapping the end portion of a metal foil material and the end portion of a metal plate material and performing friction stir spot welding is conceivable. In this case, the thickness of the joined portion becomes larger than the thickness of the metal foil material or the thickness of the metal plate material. For example, when the thickness of the joined portion becomes larger than the thickness of the metal foil material or the thickness of the metal plate material, the deformable region of the metal foil material is limited, and the flexibility of the bus bar decreases. Therefore, when the heights of two battery cases electrically connected by the bus bar are significantly different, there is a risk that the bus bar cannot be attached to at least one of the two battery cases.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a method for manufacturing a current-carrying component and a current-carrying component that can suppress the thickness of a joined portion when forming the joined portion between a metal foil material and a metal plate material using friction stir spot welding.

Means for Solving the Problems

[0006] In order to solve the aforementioned problems and achieve the objective, [1] The present invention provides a method for manufacturing an electrical component, comprising: a first step of butting together the end face of a plate-shaped metal foil material, which is formed by laminating a plurality of metal foils, with the end face of a metal sheet material, the thickness of which in the lamination direction of the plurality of metal foils is substantially the same as that of the metal foil material; and a second step of friction stirring point bonding the metal foil material and the metal sheet material by rotating a friction stir bonding tool between them so as to include a portion of the boundary between the butted end faces of the metal foil material and the end face of the metal sheet material.

[0007] [2] The method for manufacturing an electrically conductive component according to the present invention is as described in [1] above, wherein the end faces of the butted metal plate material and the end face of the metal foil material are planes substantially parallel to the lamination direction.

[0008] [3] The method for manufacturing an electrically conductive component according to the present invention is as described in [1] above, wherein the end faces of the butted metal plate material and the end face of the metal foil material are inclined surfaces that are inclined with respect to the lamination direction.

[0009] [4] The method for manufacturing an electrically conductive component according to the present invention is as described in [2] above, wherein the friction stir welding tool is cylindrical, and in the second step, the friction stir welding tool is inserted such that the central axis of the friction stir welding tool and the boundary portion are located on the same straight line.

[0010] [5] The method for manufacturing an electrically conductive component according to the present invention is as described in [3] above, wherein the friction stir welding tool is cylindrical, and in the second step, the friction stir welding tool is inserted such that the boundary portion is located within the diameter of the friction stir welding tool from one end to the other in the lamination direction.

[0011] [6] The current-carrying component according to the present invention comprises: a first metal sheet material; a second metal sheet material having substantially the same thickness as the first metal sheet material; a plate-shaped metal foil material having substantially the same thickness as the first metal sheet material and the second metal sheet material, disposed between the first metal sheet material and the second metal sheet material, with end faces facing the first metal sheet material and the second metal sheet material respectively in contact with the respective end faces of the first metal sheet material and the second metal sheet material, and formed by laminating a plurality of metal foils in the thickness direction; a first joint portion formed by friction stir point joining the first metal sheet material and the metal foil material so as to include a part of the boundary portion between the first metal sheet material and the metal foil material; and a second joint portion formed by friction stir point joining the second metal sheet material and the metal foil material so as to include a part of the boundary portion between the second metal sheet material and the metal foil material.

[0012] [7] In the invention of the present invention, the end faces of the first metal plate material and the end face of the metal foil material facing each other are planes substantially parallel to the thickness direction, and the end faces of the second metal plate material and the end face of the metal foil material facing each other are planes substantially parallel to the thickness direction.

[0013] [8] In the invention of the present invention, the electrical component according to the present invention is such that the end faces of the first metal plate material and the end face of the metal foil material facing each other are inclined surfaces that are inclined with respect to the thickness direction, and the end faces of the second metal plate material and the end face of the metal foil material facing each other are inclined surfaces that are inclined with respect to the thickness direction. [Effects of the Invention]

[0014] The method for manufacturing an electrically conductive component and the electrically conductive component according to the present invention have the effect of reducing the thickness of the joint when forming a joint between a metal foil material and a metal plate material using friction stir point welding. [Brief explanation of the drawing]

[0015] [Figure 1] A schematic plan view showing an electrical component according to Embodiment 1 of the present invention. [Figure 2] Side view of the powered component in Figure 1. [Figure 3] Cross-sectional view taken along line A-A in Figure 1 [Figure 4] Diagram showing the first step and the second step in the method for manufacturing the current-carrying component of Figure 1 [Figure 5] Diagram showing the first stage of the third step in the method for manufacturing the current-carrying component of Figure 1 [Figure 6] Diagram showing the second stage of the third step in the method for manufacturing the current-carrying component of Figure 1 [Figure 7] Diagram showing the state after completion of the third step in the method for manufacturing the current-carrying component of Figure 1 [Figure 8] Cross-sectional view showing a state where burrs are removed in the fourth step of the method for manufacturing the current-carrying component of Figure 1 [Figure 9] Diagram showing the positional relationship between the recess and the boundary portion in Figure 8 [Figure 10] Diagram showing a case where friction stir spot joining is performed with the central axis inclined relative to the boundary portion of Figure 9 [Figure 11] Diagram showing a case where the current-carrying component of Figure 1 is assembled to battery cases of different heights [Figure 12] Plan view schematically showing a current-carrying component according to Embodiment 2 of the present invention [Figure 13] Side view of the current-carrying component of Figure 12 [Figure 14] Cross-sectional view taken along line B-B in Figure 12 [Figure 15] Diagram showing the first step and the second step in the method for manufacturing the current-carrying component of Figure 12 [Figure 16] Diagram showing the first stage of the third step in the method for manufacturing the current-carrying component of Figure 12 [Figure 17] Diagram showing the second stage of the third step in the method for manufacturing the current-carrying component of Figure 12 [Figure 18] Diagram showing the state after completion of the third step in the method for manufacturing the current-carrying component of Figure 12 [Figure 19] Cross-sectional view showing a state where burrs are removed in the fourth step of the method for manufacturing the current-carrying component of Figure 12 [Figure 20] Diagram showing the positional relationship between the recess and the boundary portion in Figure 19 [Figure 21]Figure 20 shows a case where the central axis is tilted relative to the boundary portion and friction stir point bonding is performed. [Figure 22] This diagram shows the case where the end face of a metal plate is positioned on top of the end face of a metal foil and butted together. [Figure 23] Figure 22 shows a case where the end face of a metal plate is positioned on the end face of a metal foil and butted together, and the central axis is tilted relative to the boundary portion for friction stir point joining. [Figure 24] Cross-sectional view of the main part of the conductive component according to Embodiment 3 of the present invention, cut in a direction perpendicular to the thickness direction. [Modes for carrying out the invention]

[0016] (Embodiment 1) The method for manufacturing an electrically conductive component and Embodiment 1 of the electrically conductive component according to the present invention are described below. However, the present invention is not limited to this embodiment.

[0017] Figure 1 is a schematic plan view showing an electrical component 1 according to Embodiment 1 of the present invention. Figure 2 is a side view of the electrical component 1 in Figure 1. Figure 3 is a cross-sectional view along line AA in Figure 1. In the following description, the longitudinal direction of the electrical component 1 will be simply referred to as the longitudinal direction X, the width direction of the electrical component 1 will be simply referred to as the width direction Y, and the thickness direction of the electrical component 1 will be simply referred to as the thickness direction Z.

[0018] As shown in Figures 1 and 2, the conductive component 1 according to Embodiment 1 comprises a metal plate 3A (first metal plate) positioned at one end in the longitudinal direction X and a metal plate 3B (second metal plate) positioned at the other end in the longitudinal direction X, with a metal foil 2 positioned between them. Furthermore, as shown in Figure 1, holes 5A and 5B for fitting fastening members such as bolts are provided in the metal plate 3A and 3B located at both ends in the longitudinal direction X of the conductive component 1.

[0019] The metal foil material 2 is constructed by laminating multiple strip-shaped metal foils 20a, 20b, 20c, 20d, 20e, 20f, 20g, 20h, 20i, and 20j in the thickness direction Z, resulting in a plate-like structure with approximately the same thickness as the metal plate materials 3A and 3B. The lamination direction of the multiple metal foils 20a, 20b, 20c, 20d, 20e, 20f, 20g, 20h, 20i, and 20j in the metal foil material 2 is the same direction as the thickness direction Z. Furthermore, in the following description, when no particular distinction is made between the multiple metal foils 20a, 20b, 20c, 20d, 20e, 20f, 20g, 20h, 20i, and 20j, they will simply be referred to as metal foil 20. Examples of metal foil 20 include aluminum alloy foil and copper alloy foil. Furthermore, the thickness of the metal foil 20 is, for example, 0.2 mm or less.

[0020] The end face 21A of the metal foil material 2 on the metal plate material 3A side in the longitudinal direction X is formed as a plane substantially parallel to the thickness direction Z of the metal foil material 2. Furthermore, the end face 21B of the metal foil material 2 on the metal plate material 3B side in the longitudinal direction X is formed as a plane substantially parallel to the thickness direction Z of the metal foil material 2.

[0021] Examples of metal sheet materials 3A and 3B include aluminum alloy sheets and copper alloy sheets. The thickness of metal sheet materials 3A and 3B is, for example, 1 mm or more. The end face 30A of metal sheet material 3A on the metal foil material 2 side in the longitudinal direction X is formed as a plane substantially parallel to the thickness direction Z of metal sheet material 3A. Similarly, the end face 30B of metal sheet material 3B on the metal foil material 2 side in the longitudinal direction X is formed as a plane substantially parallel to the thickness direction Z of metal sheet material 3B.

[0022] At one end of the conductive component 1 in the longitudinal direction X, the end face 21A of the metal foil material 2 and the end face 30A of the metal plate material 3A are butted together (contacting) and in surface contact. At the two joints 40A and 42A, the metal foil material 2 and the metal plate material 3A are friction stir point-jointed, including a portion of the boundary portion 10A between the end face 21A of the metal foil material 2 and the end face 30A of the metal plate material 3A. As shown in Figures 1 and 3, the joints 40A and 42A are formed around the hole-shaped recesses 41A and 43A, which are insertion marks of the friction stir welding tool 8 (see Figure 4), described later, inserted at predetermined intervals in the width direction Y of the conductive component 1. The joints 40A and 42A are portions where the metal foil material 2 and the metal plate material 3A, which have undergone plastic flow due to friction stirring by the friction stir welding tool 8, are mixed together and solid-state bonded (integrated structurally and morphologically).

[0023] Furthermore, at the other end of the conductive component 1 in the longitudinal direction X, the end face 21B of the metal foil material 2 and the end face 30B of the metal plate material 3B are butted together (contacting) and in surface contact. At the two joints 40B and 42B, the metal foil material 2 and the metal plate material 3B are friction stir point-joined, including a portion of the boundary portion 10B between the end face 21B of the metal foil material 2 and the end face 30B of the metal plate material 3B. As shown in Figures 1 and 3, the joints 40B and 42B are formed around the hole-shaped recesses 41B and 43B, which are the insertion marks of the friction stir welding tool 8 inserted at a predetermined interval in the width direction Y of the conductive component 1. The joints 40B and 42B are portions where the metal foil material 2 and the metal plate material 3B, which have undergone plastic flow due to friction stirring by the friction stir welding tool 8, are mixed together and solid-state-joined.

[0024] In the conductive component 1 according to Embodiment 1, the end face 21A of the metal foil material 2 and the end face 30A of the metal plate material 3A are joined by butt joint, and the end face 21B of the metal foil material 2 and the end face 30B of the metal plate material 3B are joined by butt joint. As a result, in the conductive component 1 according to Embodiment 1, the thickness of the joint portion can be made thinner than when the metal foil material 2 and the metal plate material 3A are stacked in the thickness direction Z and joined, and when the metal foil material 2 and the metal plate material 3B are stacked in the thickness direction Z and joined. Furthermore, in the conductive component 1 according to Embodiment 1, when friction stir point welding is used to form joint portions 40A, 42A, 40B, and 42B between the metal foil material 2 and the metal plate materials 3A and 3B, the thickness of the joint portions 40A, 42A, 40B, and 42B can be reduced.

[0025] Next, a method for manufacturing the conductive component 1 according to Embodiment 1 will be described. In the method for manufacturing the conductive component 1 according to Embodiment 1, the joining method at the joints 40A and 42A between the metal foil material 2 and the metal plate material 3A, and the joining method at the joints 40B and 42B between the metal foil material 2 and the metal plate material 3B are the same. Therefore, here, we will explain using the case in which the metal foil material 2 and the metal plate material 3A are joined at the joint 40A by friction stir point welding as an example.

[0026] Figure 4 shows the first and second steps in the manufacturing method of the conductive component 1 shown in Figure 1.

[0027] First, in the first step, as shown in Figure 4, the end faces 21A of the metal foil material 2 and 30A of the metal plate material 3A, which are facing each other and are in planes substantially parallel to the thickness direction Z, are placed on the mounting base 6 in a butt-to-butt position. Then, the metal foil material 2 and the metal plate material 3A are fixed to the mounting base 6 by pressing them down from above with a plate-shaped pressing jig 71.

[0028] Next, in the second step, as shown in Figure 4, a friction stir welding tool 8 attached to a joining device (not shown) is inserted into a through hole provided in the pressing jig 71. The friction stir welding tool 8 is then positioned relative to the metal foil 2 and metal plate 3A such that its tip surface 80 is slightly separated from the upper surfaces of the metal foil 2 and metal plate 3A. At this time, the friction stir welding tool 8 is positioned such that, in the longitudinal direction X, the boundary portion 10A between the end face 21A of the metal foil 2 and the end face 30A of the metal plate 3A and the central axis C1 of the friction stir welding tool 8 are aligned on the same straight line. In this way, in the second step, the friction stir welding tool 8 is positioned such that, in the longitudinal direction X, the boundary portion 10A is located within the diameter D1 of the tip surface 80 of the friction stir welding tool 8 from the upper end (one end) to the lower end (the other end) in the thickness direction Z.

[0029] Figure 5 shows the first step of the third process in the manufacturing method of the conductive component 1 shown in Figure 1. Figure 6 shows the second step of the third process in the manufacturing method of the conductive component 1 shown in Figure 1. Figure 7 shows the state after the completion of the third process in the manufacturing method of the conductive component 1 shown in Figure 1.

[0030] In the first stage of the third process, as shown in Figure 5, the friction stir welding tool 8 is rotated at a predetermined speed in the direction of arrow R1 with its central axis C1 as the center of rotation, while being lowered in the direction of arrow M1, and inserted into the interior of the metal foil material 2 and the metal plate material 3A from its tip surface 80. At this time, the metal foil material 2 and the metal plate material 3A around the rapidly rotating friction stir welding tool 8 are softened by frictional heat and stirred by the rotational force of the friction stir welding tool 8, undergoing plastic flow and mixing together. The predetermined speed for rotating the friction stir welding tool 8 at high speed is, for example, 5000 [rpm] to 9000 [rpm].

[0031] Next, in the second stage of the third process, as shown in Figure 6, the rotation of the friction stir welding tool 8 is stopped after the tip surface 80 of the friction stir welding tool 8 reaches a predetermined position in the thickness direction Z where it does not penetrate the metal foil material 2 and the metal plate material 3A. Then, the friction stir welding tool 8 is raised in the direction of arrow M2 and withdrawn from inside the metal foil material 2 and the metal plate material 3A. As a result, as shown in Figure 7, a joint portion 40A is formed around the recess 41A, which is the insertion point of the friction stir welding tool 8, where the metal foil material 2 and the metal plate material 3A are friction stir-bonded (solid-phase bonded). Also, as shown in Figure 7, a burr 400A is formed on the periphery of the recess 41A. This burr 400A is formed when a portion of the metal foil material 2 and the metal plate material 3A, which have undergone plastic flow due to friction stirring, enters the gap between the friction stir welding tool 8 and the pressing jig 71.

[0032] Figure 8 is a cross-sectional view showing the state after the burr 400A has been removed in the fourth step of the manufacturing method of the conductive component 1 shown in Figure 1. Figure 9 is a diagram showing the positional relationship between the recess 41A and the boundary portion 10A in Figure 8.

[0033] In the fourth step, the retaining jig 71 that held the metal foil material 2 and metal plate material 3A in place is removed to secure working space around the burr 400A, and the burr 400A is removed by any deburring method such as cutting, as shown in Figure 8.

[0034] In the manufacturing method of the conductive component 1 according to Embodiment 1, the joint portion 42A between the metal foil material 2 and the metal plate material 3A, and the joint portions 40B and 42B between the metal foil material 2 and the metal plate material 3B are similarly carried out from the first to the fourth steps to complete the manufacturing of the conductive component 1.

[0035] As described above, the manufacturing method for the conductive component 1 according to Embodiment 1 makes it possible to manufacture a conductive component 1 in which the thickness of the joints 40A, 42A, 40B, and 42B is reduced so that they are approximately the same thickness as the thickness of the metal foil material 2 and the metal plate materials 3A and 3B, respectively. Furthermore, in the manufacturing method for the conductive component 1 according to Embodiment 1, since the thickness of the joint 40A is reduced, interference between the joint 40A and the surrounding components becomes less likely, thus improving the degree of freedom in component design.

[0036] Furthermore, in the manufacturing method of the conductive component 1 according to Embodiment 1, as shown in Figure 9, the tip surface 80 of the friction stir welding tool 8 is inserted into the metal foil material 2 and the metal plate material 3A so that the boundary portion 10A is located within the recess 41A in the longitudinal direction X, and friction stir point welding is performed. As a result, in the manufacturing method of the conductive component 1 according to Embodiment 1, friction stir point welding can be performed while suppressing the curling of the metal foil 20 constituting the metal foil material 2.

[0037] Furthermore, the manufacturing method of the conductive component 1 according to Embodiment 1 is not limited to friction stir point joining by positioning the central axis C1 of the friction stir welding tool 8 and the boundary portion 10A on the same straight line in the longitudinal direction X. For example, as long as the boundary portion 10A is located within the recess 41A (diameter D1 of the tip surface 80 of the friction stir welding tool 8) in the longitudinal direction X, the central axis C1 and the boundary portion 10A may be parallel to each other and offset from each other.

[0038] Figure 10 shows the case where friction stir point joining is performed by tilting the central axis C1 with respect to the boundary portion 10A in Figure 9.

[0039] Furthermore, in the manufacturing method of the conductive component 1 according to Embodiment 1, for example, as shown in Figure 10, the central axis C1 may be tilted by a predetermined angle with respect to the boundary portion 10A so that the friction stir welding tool 8 moves closer to the metal foil material 2 side, and friction stir point welding may be performed. This allows the tip surface 80 of the friction stir welding tool 8 to be inserted mainly from the metal foil material 2 side, and the metal foil material 2 and the metal plate material 3A to be friction stir point welded. Therefore, it is possible to insert the tip surface 80 of the friction stir welding tool 8 with a smaller rotation speed and rotational force than when the tip surface 80 of the friction stir welding tool 8 is inserted into both the metal foil material 2 and the metal plate material 3A almost simultaneously.

[0040] Figure 11 shows the case where the powered component 1 from Figure 1 is assembled into battery cases 300A and 300B of different heights.

[0041] The power-carrying component 1 according to Embodiment 1 can be used, for example, as a busbar to electrically connect multiple battery cases mounted in an electric vehicle.

[0042] For example, in the conductive component 1 according to Embodiment 1, as shown in Figure 11, it is used as a busbar to electrically connect battery cases 300A and 300B of different heights. When the conductive component 1 is assembled to battery cases 300A and 300B of different heights in this way, the metal foil material 2 deforms flexibly according to the difference between the height h1 of battery case 300A and the height h2 of battery case 300B. In particular, in the conductive component 1 according to Embodiment 1, the end face 21A of the metal foil material 2 and the end face 30A of the metal plate material 3A, and the end face 21B of the metal foil material 2 and the end face 30B of the metal plate material 3B are joined by butt joints, so the range of motion of the metal foil material 2 can be designed to be wide. This improves the flexibility of the conductive component 1 (metal foil material 2) according to Embodiment 1. Therefore, when fastening the metal plates 3A and 3B of the conductive component 1 to the connection parts 301A and 301B of the battery cases 300A and 300B using the fastening members, bolts 302A and 302B, workability can be improved. In addition, the flexible deformation of the metal foil material 2 can prevent the contact area between the metal plates 3A and 3B fastened by the bolts 302A and 302B and the connection parts 301A and 301B from decreasing.

[0043] Furthermore, the acceptable height difference between battery cases 300A and 300B can be made larger compared to a conductive component (busbar) made solely of metal plate material. Therefore, the thickness of the conductive component 1 according to Embodiment 1 can be made large enough to accommodate high currents of, for example, 1000[A] or more.

[0044] As described above, in the conductive component 1 according to Embodiment 1, the thickness of the joints 40A, 42A, 40B, and 42B can be reduced, and the deformable area of ​​the metal foil material 2 is large, so it can be manufactured as a busbar with high flexibility. As a result, when the conductive component 1 according to Embodiment 1 is used as a busbar, the high flexibility of the busbar makes it easier to assemble the busbar to the battery cases 300A and 300B. Furthermore, if a large displacement occurs in the battery cases 300A and 300B due to vibration or the like, the high flexibility of the busbar allows it to deform in accordance with the displacement, making it less likely for the busbar to break at the bolt fastening portion.

[0045] (Embodiment 2) The method for manufacturing an electrically conductive component and Embodiment 2 of the electrically conductive component according to the present invention will be described below. In Embodiment 2, the same explanations as in Embodiment 1 will be omitted as appropriate.

[0046] Figure 12 is a schematic plan view showing the conductive component 101 according to Embodiment 2 of the present invention. Figure 13 is a side view of the conductive component 101 in Figure 12. Figure 14 is a cross-sectional view along line BB in Figure 12.

[0047] As shown in Figures 12 and 13, the conductive component 101 according to Embodiment 2 is constructed by arranging a metal foil material 102 between a metal plate material 103A (first metal plate material) and a metal plate material 103B (second metal plate material) in the longitudinal direction X. Furthermore, as shown in Figure 12, holes 105A and 105B for fitting fastening members such as bolts are provided in the metal plate materials 103A and 103B located at both ends in the longitudinal direction X of the conductive component 101. The conductive component 101 according to Embodiment 2 can be used, for example, as a busbar to electrically connect multiple battery cases mounted on an electric vehicle.

[0048] The metal foil material 102 is constructed by laminating multiple strip-shaped metal foils 120a, 120b, 120c, 120d, 120e, 120f, 120g, 120h, 120i, and 120j in the thickness direction Z, resulting in a plate-like structure with approximately the same thickness as the metal plate materials 103A and 103B. The lamination direction of the multiple metal foils 120a, 120b, 120c, 120d, 120e, 120f, 120g, 120h, 120i, and 120j in the metal foil material 102 is the same direction as the thickness direction Z. Furthermore, in the following description, when no particular distinction is made between multiple metal foils 120a, 120b, 120c, 120d, 120e, 120f, 120g, 120h, 120i, and 120j, they will simply be referred to as metal foil 120. Examples of metal foil 120 include aluminum alloy foil and copper alloy foil. The thickness of metal foil 120 is, for example, 0.2 [mm] or less.

[0049] The end face 121A of the metal foil material 102 on the metal sheet material 103A side in the longitudinal direction X is an inclined surface that slopes downward from the outside to the inside in the longitudinal direction X, from the upper end (one end) to the lower end (the other end) in the thickness direction Z. Similarly, the end face 121B of the metal foil material 102 on the metal sheet material 103B side in the longitudinal direction X is formed as an inclined surface that slopes downward from the outside to the inside in the longitudinal direction X, from the upper end (one end) to the lower end (the other end) in the thickness direction Z.

[0050] Examples of metal sheet materials 103A and 103B include aluminum alloy sheets and copper alloy sheets. The thickness of the metal sheet materials 103A and 103B is, for example, 1 mm or more. The end face 130A of the metal sheet material 103A on the metal foil material 102 side in the longitudinal direction X is an inclined surface that slopes downward from the inside to the outside in the longitudinal direction X, from the upper end (one end) to the lower end (the other end) in the thickness direction Z. Similarly, the end face 130B of the metal sheet material 103B on the metal foil material 102 side in the longitudinal direction X is an inclined surface that slopes downward from the inside to the outside in the longitudinal direction X, from the upper end (one end) to the lower end (the other end) in the thickness direction Z.

[0051] At one end of the conductive component 101 in the longitudinal direction X, the end face 121A of the metal foil material 102 and the end face 130A of the metal plate material 103A are butted together and in surface contact, such that the end face 121A of the metal foil material 102 in the thickness direction Z is positioned above the end face 130A of the metal plate material 103A. At the two joints 140A and 142A, the metal foil material 102 and the metal plate material 103A are friction stir point joined, including a portion of the boundary portion 110A between the end face 121A of the metal foil material 102 and the end face 130A of the metal plate material 103A. As shown in Figures 12 and 14, the joints 140A and 142A are formed around the hole-shaped recesses 141A and 143A, which are the insertion marks of a friction stir welding tool 108 (see Figure 15), described later, inserted at a predetermined interval in the width direction Y of the conductive component 101. The joints 140A and 142A are portions where the metal foil material 102 and the metal plate material 103A, which have undergone plastic flow due to friction stirring by the friction stir welding tool 108, are mixed together and solid-state bonded (integrated structurally and morphologically).

[0052] Furthermore, at the other end of the conductive component 101 in the longitudinal direction X, the end face 121B of the metal foil material 102 and the end face 130B of the metal plate material 103B are butted together and in surface contact, such that the end face 121B of the metal foil material 102 in the thickness direction Z is positioned above the end face 130B of the metal plate material 103B. At the two joints 140B and 142B, the metal foil material 102 and the metal plate material 103B are friction stir point joined, including a portion of the boundary portion 110B between the end face 121B of the metal foil material 102 and the end face 130B of the metal plate material 103B. As shown in Figures 12 and 14, the joints 140B and 142B are formed around the hole-shaped recesses 141B and 143B, which are the insertion marks of the friction stir welding tool 108 inserted at predetermined intervals in the width direction Y of the conductive component 101. The joints 140B and 142B are areas where the metal foil material 102 and the metal plate material 103B, which have undergone plastic flow due to friction stirring by the friction stir welding tool 108, are mixed together and solid-state bonded.

[0053] In the conductive component 101 according to Embodiment 2, the end face 121A of the metal foil material 102 and the end face 130A of the metal plate material 103A are joined by butt joint, and the end face 121B of the metal foil material 102 and the end face 130B of the metal plate material 103B are joined by butt joint. As a result, in the conductive component 101 according to Embodiment 2, the thickness of the joint portion can be made thinner than when the metal foil material 102 and the metal plate material 103A are stacked in the thickness direction Z and joined, and when the metal foil material 102 and the metal plate material 103B are stacked in the thickness direction Z and joined. Furthermore, in the conductive component 101 according to Embodiment 2, when friction stir point welding is used to form joint portions 140A, 142A, 140B, and 142B between the metal foil material 102 and the metal plate materials 103A and 103B, the thickness of the joint portions 140A, 142A, 140B, and 142B can be reduced.

[0054] Furthermore, in the conductive component 101 according to Embodiment 2, the end face 121A of the metal foil material 102 and the end face 130A of the metal plate material 103A are inclined surfaces that are inclined with respect to the thickness direction Z. As a result, the conductive component 101 according to Embodiment 2 can have a larger contact area with each other than when the end face 121A of the metal foil material 102 and the end face 130A of the metal plate material 103A are planes substantially parallel to the thickness direction Z, thereby improving bonding performance.

[0055] Next, a method for manufacturing the conductive component 101 according to Embodiment 2 will be described. In the method for manufacturing the conductive component 101 according to Embodiment 2, the joining method at the joints 140A and 142A between the metal foil material 102 and the metal plate material 103A, and the joining method at the joints 140B and 142B between the metal foil material 102 and the metal plate material 103B are the same. Therefore, here, we will explain using the case in which the metal foil material 102 and the metal plate material 103A are joined at the joint 140A by friction stir point welding as an example.

[0056] Figure 15 shows the first and second steps in the manufacturing method of the conductive component 101 shown in Figure 12.

[0057] First, in the first step, as shown in Figure 15, the end faces 121A of the metal foil material 102 and 130A of the metal plate material 103A, which are inclined surfaces with respect to the thickness direction Z and face each other, are placed on the mounting base 106 in a butt-to-contact state. Then, the metal foil material 102 and the metal plate material 103A are fixed on the mounting base 106 by pressing down from above with a plate-shaped pressing jig 171.

[0058] Next, in the second step, as shown in Figure 15, a friction stir welding tool 108, attached to a joining device (not shown), is inserted into a through hole provided in the pressing jig 171. The friction stir welding tool 108 is then positioned relative to the metal foil material 102 and the metal plate material 103A such that its tip surface 180 is slightly separated from the upper surfaces of the respective metal foil material 102 and metal plate material 103A. At this time, in the longitudinal direction X, the boundary portion 110A between the end surface 121A of the metal foil material 102 and the end surface 130A of the metal plate material 103A is positioned within the diameter D2 of the tip surface 180 of the friction stir welding tool 108 from the upper end (one end) to the lower end (the other end) in the thickness direction Z.

[0059] Figure 16 shows the first step of the third process in the manufacturing method of the conductive component 101 shown in Figure 12. Figure 17 shows the second step of the third process in the manufacturing method of the conductive component 101 shown in Figure 12. Figure 18 shows the state after the completion of the third process in the manufacturing method of the conductive component 101 shown in Figure 12.

[0060] In the first stage of the third process, as shown in Figure 16, the friction stir welding tool 108 is rotated at a predetermined speed in the direction of arrow R2 with its central axis C2 as the center of rotation, while being lowered in the direction of arrow M3, and inserted into the interior of the metal foil material 102 and the metal plate material 103A from its tip surface 180. At this time, the metal foil material 102 and the metal plate material 103A around the rapidly rotating friction stir welding tool 108 are softened by frictional heat and stirred by the rotational force of the friction stir welding tool 8, undergoing plastic flow and mixing together. The predetermined speed for rotating the friction stir welding tool 108 at high speed is, for example, 5000 [rpm] to 9000 [rpm].

[0061] Next, in the second stage of the third process, as shown in Figure 17, the rotation of the friction stir welding tool 108 is stopped after the tip surface 180 of the friction stir welding tool 108 reaches a predetermined position in the thickness direction Z where it does not penetrate the metal foil material 102 and the metal plate material 103A. Then, the friction stir welding tool 108 is raised in the direction of arrow M4 and withdrawn from inside the metal foil material 102 and the metal plate material 103A. As a result, as shown in Figure 18, a joint portion 140A is formed around the recess 141A, which is the insertion point of the friction stir welding tool 108, where the metal foil material 102 and the metal plate material 103A are friction stir-bonded (solid-phase bonded). Also, as shown in Figure 18, a burr 1400A is formed on the periphery of the recess 141A. This burr 1400A is formed when a portion of the metal foil material 102 and the metal plate material 103A, which have undergone plastic flow by friction stir, enters the gap between the friction stir joining tool 108 and the pressing jig 171.

[0062] Figure 19 is a cross-sectional view showing the state after the burr 1400A has been removed in the fourth step of the manufacturing method of the conductive component 101 shown in Figure 12. Figure 20 is a diagram showing the positional relationship between the recess 141A and the boundary portion 110A in Figure 19.

[0063] In the fourth step, the retaining jig 171 that held the metal foil material 102 and the metal plate material 103A in place is removed to secure working space around the burr 1400A, and the burr 1400A is removed by any deburring method such as cutting, as shown in Figure 19.

[0064] In the manufacturing method of the conductive component 101 according to Embodiment 2, the joint portion 142A between the metal foil material 102 and the metal plate material 103A, and the joint portions 140B and 142B between the metal foil material 102 and the metal plate material 103B are similarly carried out from the first to the fourth steps. This completes the manufacturing of the conductive component 101 according to Embodiment 2.

[0065] As described above, the manufacturing method for the conductive component 101 according to Embodiment 2 makes it possible to manufacture a conductive component 101 in which the thickness of the joints 140A, 142A, 140B, and 142B is reduced so that they are approximately the same thickness as the thickness of the metal foil material 102 and the metal plate materials 103A and 103B, respectively. As a result, in the manufacturing method for the conductive component 101 according to Embodiment 2, interference between the joints 140A, 142A, 140B, and 142B and the surrounding components is reduced, thereby improving the degree of freedom in component design.

[0066] Furthermore, in the conductive component 101 according to Embodiment 2, the thickness of the joints 140A, 142A, 140B, and 142B can be reduced, and the deformable area of ​​the metal foil material 102 is large, so it can be manufactured as a busbar with high flexibility.

[0067] Furthermore, in the manufacturing method of the conductive component 101 according to Embodiment 2, as shown in Figure 20, the tip surface 180 of the friction stir welding tool 108 is inserted into the metal foil material 102 and the metal plate material 103A so that the boundary portion 110A is located within the recess 141A in the longitudinal direction X, and friction stir point welding is performed. As a result, in the manufacturing method of the conductive component 101 according to Embodiment 2, friction stir point welding can be performed while suppressing the curling of the metal foil 120 constituting the metal foil material 102.

[0068] Figure 21 shows the case where the central axis C2 is tilted with respect to the boundary portion 110A in Figure 20 for friction stir point joining.

[0069] In the manufacturing method of the conductive component 101 according to Embodiment 2, for example, as shown in Figure 21, the central axis C2 may be tilted by 90° with respect to the boundary portion 110A so that the friction stir welding tool 108 moves closer to the metal foil material 102 side, and friction stir point welding may be performed. This allows the tip surface 180 of the friction stir welding tool 108 to be inserted mainly from the metal foil material 102 side, thereby friction stir point welding of the metal foil material 102 and the metal plate material 103A. Therefore, it is possible to insert the tip surface 180 of the friction stir welding tool 108 with a smaller rotational speed and rotational force than when the tip surface 180 of the friction stir welding tool 108 is inserted into both the metal foil material 102 and the metal plate material 103A almost simultaneously.

[0070] Figure 22 shows the case where the end face 130A of a metal plate material 103A is positioned on the end face 121A of a metal foil material 102 and butted together. Figure 23 shows the case where the end face 130A of a metal plate material 103A is positioned on the end face 121A of a metal foil material 102 as in Figure 22 and butted together, and the central axis C2 is tilted with respect to the boundary portion 110A for friction stir point joining.

[0071] In the manufacturing method of the conductive component 101 according to Embodiment 2, for example, as shown in Figure 22, the end face 121A of the metal foil material 102 may be an inclined surface that slopes downward from the top end to the bottom end in the thickness direction Z and from the inside to the outside in the longitudinal direction X. Alternatively, the end face 130A of the metal plate material 103A may be an inclined surface that slopes downward from the top end to the bottom end in the thickness direction Z and from the outside to the inside in the longitudinal direction X. In the manufacturing method of the conductive component 101 according to Embodiment 2, the end face 130A of the metal plate material 103A may be butted together so that the end face 130A of the metal plate material 103A is positioned on the end face 121A of the metal foil material 102 in the thickness direction Z, and the first to fourth steps described above may be carried out to perform friction stir point welding. In this case, for example, as shown in Figure 23, the central axis C2 may be tilted by 90° with respect to the boundary portion 110A so that the friction stir welding tool 108 is closer to the metal plate material 103A side, and friction stir point welding may be performed.

[0072] (Embodiment 3) The following describes a method for manufacturing an electrically conductive component and Embodiment 3 of the electrically conductive component according to the present invention. In Embodiment 3, explanations similar to those in Embodiment 1 will be omitted as appropriate. The method for manufacturing an electrically conductive component according to Embodiment 3 is basically the same as the method for manufacturing an electrically conductive component according to Embodiment 1, except for the time during which a high-speed rotating friction stir welding tool is inserted to frictionally stir the metal foil and metal plate materials. Furthermore, in the electrically conductive component according to Embodiment 3, the condition of the joint between the metal foil and metal plate materials is basically the same as that of the electrically conductive component according to Embodiment 1, except for the state of the joint.

[0073] Figure 24 is a cross-sectional view of the main part of the conductive component 901 according to Embodiment 3 of the present invention, cut in a direction perpendicular to the thickness direction Z.

[0074] In the conductive component 901 according to Embodiment 3, at one end of the conductive component 901 in the longitudinal direction X, as shown in Figure 24, the end face 921A of the metal foil material 902, which is made up of multiple laminated metal foils, and the end face 930A of the metal plate material 903A are brought into surface contact by butting (contacting). The end faces 921A of the metal foil material 902 and 930A of the metal plate material 903A that are butting against each other are planes that are substantially parallel to the thickness direction Z. The metal foil material 902 and the metal plate material 903A are friction stir point-bonded by a friction stir welding tool (not shown) so as to include a part of the boundary portion 910A between the end face 921A of the metal foil material 902 and the end face 930A of the metal plate material 903A.

[0075] In the manufacturing method of the conductive component 901 according to Embodiment 3, the friction stir welding tool is inserted into the interior of the metal foil material 902 and the metal plate material 903A from the tip surface of the friction stir welding tool while rotating at a predetermined speed in the direction of arrow R3 with the central axis C3 as the center of rotation. At this time, the time from when the tip surface of the friction stir welding tool comes into contact with the metal foil material 902 and the metal plate material 903A until it reaches a predetermined position in the thickness direction Z and the withdrawal of the friction stir welding tool begins is set to be shorter than in the manufacturing method of the conductive component 1 according to Embodiment 1. In other words, in the manufacturing method of the conductive component 901 according to Embodiment 3, the time spent inserting the high-speed rotating friction stir welding tool and frictionally stirring the metal foil material 902 and the metal plate material 903A is shorter than in the manufacturing method of the conductive component 1 according to Embodiment 1.

[0076] As a result, in the conductive component 901 according to Embodiment 3, a joint portion 940A is formed along the rotational direction of the friction stir welding tool, around the entire circumference of the recess 941A, which is the insertion mark of the friction stir welding tool. The joint portion 940A is a solid-phase joint where a portion of the metal foil material 902 plastically flows toward the metal plate material 903A due to the rotational force of the friction stir welding tool, and the metal foil material 902 and the metal plate material 903A are softened by frictional heat and stirred and mixed by the rotational force.

[0077] Furthermore, in the electrically conductive component 901 according to Embodiment 3, a portion of the metal plate material 903A is pulled by the rotational force of the friction stir welding tool, and the plastically flowed portion 9031A of the plate material towards the metal foil material 902 is formed in a part of the periphery of the recess 941A via the joint portion 940A.

[0078] The sheet material flow section 9031A is formed, for example, around the central axis C3 of the friction stir welding tool, extending from the boundary portion 910A toward the metal foil material 902, along the perimeter of the recess 941A in an angular range of approximately 90°. However, the angular range for forming the sheet material flow section 9031A is not limited to an angular range of approximately 90°.

[0079] In the conductive component 901 according to Embodiment 3, a portion of the metal plate material 903A, which is stronger than the metal foil material 902, undergoes plastic flow toward the metal foil material 902, thereby increasing the fracture strength of the metal foil material 902 and improving the fracture strength of the entire component.

[0080] In addition, for the conductive component 901 according to Embodiment 3, the end faces 921A of the metal foil material 902 and 930A of the metal plate material 903A that abut each other may be inclined surfaces with respect to the thickness direction Z. In this case, the manufacturing method for the conductive component 901 according to Embodiment 3 is basically the same as the manufacturing method for the conductive component 101 according to Embodiment 2, except for the time during which a high-speed rotating friction stir welding tool is inserted to frictionally stir the metal foil material and the metal plate material. [Explanation of Symbols]

[0081] 1,101,901 Conductive components 2,102,902 Metal foil material 3A,103A,903A Metal plate material 3B,103B Metal plate material 5A,5B,105A,105B hole 6,106 installation stand 8,108 Friction stir welding tools 10A,110A,910A boundary part 10B,110B boundary part 20,120 metal foils 21A,30A,121A,130A,921A,930A End face 21B, 30B, 121B, 130B end face 40A,42A,140A,142A,940A joint 40B,42B,140B,142B joint 41A, 43A, 141A, 143A recess 41B, 43B, 141B, 143B recess 71,171 Pressing jigs 80,180 Tip surface 300A, 300B Battery Case 301A, 301B connection section 302A, 302B bolts 400A, 1400A burrs 9031A Plate flow section

Claims

1. A first step involves butting the end face of a plate-shaped metal foil material, which is formed by laminating multiple metal foils, with the end face of a metal sheet material, the thickness of which in the lamination direction of the multiple metal foils is approximately the same as that of the metal foil material. A second step involves frictionally stirring and spot bonding the metal foil and the metal sheet by rotating a friction stir welding tool between them, so as to include a portion of the boundary between the butted end faces of the metal foil and the metal sheet. Having, A method for manufacturing electrically conductive components, characterized by the following:

2. The end faces of the metal plate material and the end face of the metal foil material that are joined together are planes substantially parallel to the lamination direction. A method for manufacturing an electrical component according to claim 1.

3. The end faces of the metal plate material and the end face of the metal foil material that are joined together are inclined surfaces that are inclined with respect to the lamination direction. A method for manufacturing an electrical component according to claim 1.

4. The friction stir welding tool is cylindrical, In the second step, the friction stir welding tool is inserted such that the central axis of the friction stir welding tool and the boundary portion are aligned on the same straight line. The method for manufacturing an electrical component according to claim 2.

5. The friction stir welding tool is cylindrical, In the second step, the friction stir welding tool is inserted such that the boundary portion is located within the diameter of the friction stir welding tool from one end to the other in the stacking direction. The method for manufacturing an electrical component according to claim 3.

6. The first metal sheet material, A second metal sheet having approximately the same thickness as the first metal sheet, A plate-shaped metal foil material having substantially the same thickness as the first metal plate material and the second metal plate material, positioned between the first metal plate material and the second metal plate material, with end faces facing the first metal plate material and the second metal plate material respectively in contact with the respective end faces of the first metal plate material and the second metal plate material, and formed by laminating multiple metal foils in the thickness direction, A first joint is formed by friction stir point bonding the first metal plate and the metal foil, including a portion of the boundary between the first metal plate and the metal foil, A second joint is formed by friction stirring point bonding the second metal plate and the metal foil, including a portion of the boundary between the second metal plate and the metal foil, Equipped with, A conductive component characterized by the following features.

7. The end faces of the first metal plate and the end face of the metal foil, which face each other, are planes substantially parallel to the thickness direction. The end faces of the second metal plate and the end face of the metal foil, which are opposite each other, are planes substantially parallel to the thickness direction. The electrically conductive component according to feature 6.

8. The end faces of the first metal plate and the end face of the metal foil, which face each other, are inclined surfaces that are inclined with respect to the thickness direction. The end faces of the second metal plate and the end face of the metal foil, which face each other, are inclined surfaces that are inclined with respect to the thickness direction. The electrically conductive component according to feature 6.

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