Joined body manufacturing method and joined body manufacturing apparatus

Abstract

To provide a joined body manufacturing method and a joined body manufacturing apparatus which can suppress rotation wobbling of a friction-stirring joining tool to enable the friction-stirring joining tool to be moved accurately, in overlapping / superposing joining.SOLUTION: A joined body manufacturing method according to the present invention, which manufactures a joined body 1 in which two or more laminated metal members P to be joined are joined to each other by friction stirring, comprises: a step (a step S101) of laminating the members P to be joined so that at least portions thereof overlap with each other; a step (a step S102) of forming a joined guide WL at joined portions of the members P to be joined; and a step (a step S103) of moving a friction-stirring joining tool 2 along the joined guide WL while pressing the tool against the welded guide WL to join the members P to be joined to each other by friction-stirring, where the joined guide WL becomes concave or penetrates through in a laminating direction of the members P to be joined, from a surface of the joined body 1.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a joined body and a joined body manufacturing apparatus.

Background Art

[0002] As a method for joining metal members, there is a friction stir welding method (FSW). After placing the members to be joined in contact with each other, a friction stir welding tool is rotated and pressed against the portion to be joined of the members to be joined. Then, the rotating friction stir welding tool is moved while being pressed against the members to be joined. In this method, the members to be joined are softened by the frictional heat generated by rotating the friction stir welding tool and pressing it against the members to be joined, and the friction stir welding tool stirs that portion to join the members to be joined together.

[0003] There are several types of friction stir welding methods. For example, there are a superimposed joint in which the members to be joined are stacked and joined from the stacking direction, and a butted joint in which the side surfaces of the members to be joined are butted against each other and the interface is joined. In the case of the superimposed joint, during friction stir welding, meandering due to the rotational deviation of the friction stir welding tool is likely to occur on the members to be joined. Therefore, it is difficult to accurately move the friction stir welding tool on the members to be joined, and high-precision joint quality cannot be maintained. Furthermore, in the case of a robot-type friction stir welding apparatus, the meandering due to the rotational deviation of the friction stir welding tool becomes more prominent. As a method for suppressing the rotational deviation of the friction stir welding tool during progress, for example, Patent Document 1 discloses a friction stir welding method using a guide member for the friction stir welding tool adapted to a desired joint locus.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Regarding the friction stir welding method disclosed in Patent Document 1, the inventors have found the following problems. The friction stir welding method disclosed in Patent Document 1 uses a guide member that suppresses the housing of the friction stir welding tool. By continuously restricting the lateral movement range of the friction stir welding tool, the rotational deviation of the friction stir welding tool can be suppressed. However, in the friction stir welding method disclosed in Patent Document 1, a guide member that matches the desired welding trajectory is required. Therefore, it is necessary to change the guide member every time the desired welding trajectory changes, which is costly and time-consuming.

[0006] The present invention has been made to solve such problems, and in the case of lap joint, it provides a method for manufacturing a joined body and a joined body manufacturing apparatus that can suppress the rotational deviation of a friction stir welding tool and can accurately move the friction stir welding tool.

Means for Solving the Problems

[0007] The method for manufacturing a joined body according to the present invention is a method for manufacturing a joined body in which two or more stacked metal members to be joined are joined by friction stir welding, comprising a step of stacking the members to be joined so that at least a part of them overlaps each other, a step of forming a joining guide in a portion where the members to be joined are to be joined, and a step of pressing a friction stir welding tool against the joining guide and moving it along the joining guide to join the members to be joined by friction stir welding, wherein the joining guide is concave or penetrating in the stacking direction of the members to be joined from the surface of the joined body.

[0008] Here, it is preferable to form the joining guide while heating the members to be joined.

[0009] Also, it is preferable to perform the joining by friction stir welding in a state where the temperature of the joining guide is 200°C or higher.

[0010] The bonding body manufacturing apparatus according to the present invention is a bonding body manufacturing apparatus that bonds two or more stacked metal members to be joined by friction stir welding, and includes a bonding guide forming portion that forms a bonding guide at a portion of the members to be joined, and a friction stir welding tool that presses against the bonding guide and moves along the bonding guide to bond the members to be joined by friction stir welding. The bonding guide is concave or penetrating in the stacking direction of the members to be joined from the surface of the bonding body.

[0011] Here, it is preferable that the bonding guide forming portion forms the bonding guide while heating the members to be joined.

Effect of the Invention

[0012] According to the present invention, in the lap joint, it is possible to suppress the rotational deviation of the friction stir welding tool and to move the friction stir welding tool accurately, and to provide a method for manufacturing a bonded body and a bonded body manufacturing apparatus.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0014] Embodiment 1 Hereinafter, with reference to the drawings, a method for manufacturing a joined body according to Embodiment 1 will be described. In this embodiment, friction stir welding is used as the method for manufacturing the joined body. The friction stir welding in this embodiment is a butt joint in which the members to be joined are stacked and joined from the stacking direction.

[0015] First, the configuration of a joined body manufacturing apparatus for realizing the method for manufacturing a joined body according to Embodiment 1 will be described with reference to FIG. 1. As shown in FIG. 1, the joined body manufacturing apparatus 100 includes a friction stir welding tool 2, a joining guide forming unit 3, a control device 4, and a robot arm 5. The joined body manufacturing apparatus 100 is a robot-type friction stir welding apparatus including an articulated robot arm 5. Using the joined body manufacturing apparatus 100, the members P to be joined are joined to obtain a joined body 1.

[0016] As shown in FIG. 1, the joined body manufacturing apparatus 100 according to this embodiment stacks two or more members P to be joined in the thickness direction, presses the friction stir welding tool 2 against the overlapping portion of the members P to be joined while rotating it, and moves it in a predetermined direction, thereby joining the members P to be joined to each other.

[0017] Here, the joined body 1 includes two or more stacked members P to be joined, and is obtained by joining the members P to be joined to each other by friction stir welding. Examples of the use of the joined body 1 in this embodiment include a battery case and a battery cooler. The member P to be joined is a metal, and all the members P to be joined used for the joined body 1 are not limited to the same metal material, and different metal materials may be used as the members P to be joined. The member P to be joined shown in FIG. 1 has a flat plate shape, but is not limited thereto, and may have a curved surface or an uneven shape.

[0018] The friction stir welding tool 2 is a member that abuts against the members P to be joined and performs friction stir welding. The friction stir welding tool 2 is attached to the robot arm 5. As shown in FIG. 2, the friction stir welding tool 2 includes a tool body 21 and a probe 22. The probe 22 is provided at the tip of the columnar tool body 21. The tool body 21 supports the probe 22 and is rotationally driven about the X axis shown in FIG. 2 by a built-in drive mechanism.

[0019] The length of the probe 22 and the penetration length of the probe 22 into the members P to be joined are adjusted according to the thickness and material of the members P to be joined. Further, in the present embodiment, friction stir welding is performed by moving the probe 22 along the joining guide WL on the members P to be joined. Therefore, the tip shape of the probe 22 preferably has a rounded shape in consideration of the ease of entry of the probe 22 into the joining guide WL, but may also have a flat shape or corners. As the material of the probe 22 of the friction stir welding tool 2, materials having a higher hardness than the members P to be joined, such as steel, cemented carbide, and ceramics, may be used.

[0020] Furthermore, with reference to FIG. 1, the joining guide forming portion 3 provided in the joined body manufacturing apparatus 100 will be described. The joining guide forming portion 3 forms a joining guide WL for guiding the probe 22 on the members P to be joined before performing friction stir welding in order to suppress the meandering due to the rotational deviation of the friction stir welding tool 2 during friction stir welding. The joining guide forming portion 3 preferably can form the joining guide WL with heating of the members P to be joined. For example, the joining guide forming portion 3 may form the joining guide WL using plasma, laser, or gas. In the present embodiment, the joining guide forming portion 3 is provided on the robot arm 5 provided with the friction stir welding tool 2, but the friction stir welding tool 2 and the joining guide forming portion 3 may be provided on separate robot arms 5. Further, the joining guide forming portion 3 is not limited to being integrated as the joined body manufacturing apparatus 100, and the user may manually form the joining guide WL using the joining guide forming portion 3.

[0021] The control device 4 is provided in the joined body manufacturing device 100, and controls the movement of the robot arm 5, the rotation speed of the friction stir welding tool 2, the penetration length into the workpiece P, and the like. The control device 4 can input setting data for realizing these operations and the like in advance. The setting data is stored in a storage unit (not shown) in the control device 4. The control device 4 mainly controls the movement of the robot arm 5 to control the probe 22 of the friction stir welding tool 2 and the joining guide forming portion 3 to move along the joining locus on the workpiece P. In particular, the control device 4 in the present embodiment moves both of them in the stacking direction of the workpiece P so that either one of the probe 22 of the friction stir welding tool 2 and the joining guide forming portion 3 selectively contacts the surface of the workpiece P. Also, the control device 4 adjusts the width and depth of the joining locus WA by controlling the movement of the robot arm 5, the rotation speed of the friction stir welding tool 2, the penetration length into the workpiece P, and the like. Further, the control device 4 also controls the driving conditions of the joining guide forming portion 3 to adjust the width and depth of the joining guide WL.

[0022] The tip of the robot arm 5 is provided with a friction stir welding tool 2 and a joining guide forming portion 3. As shown in FIG. 1, in the present embodiment, one robot arm 5 is provided with a friction stir welding tool 2 and a joining guide forming portion 3, but the friction stir welding tool 2 and the joining guide forming portion 3 may be separately provided on separate robot arms 5. The robot arm 5 moves the friction stir welding tool 2 and the joining guide forming portion 3 in response to a command from the control device 4.

[0023] Subsequently, the manufacturing method of the joined body according to the first embodiment will be described. FIG. 3 is a flowchart of the manufacturing method of the joined body according to the first embodiment.

[0024] First, a step of laminating two or more joined members P so that at least a part of each member overlaps with the others is performed (step S101). Since a joining locus WA is formed in the overlapping portion of the joined members P, it is preferable that the overlapping width of the joined members P is larger than the width of the assumed joining locus WA.

[0025] Next, a step of driving the joining guide forming unit 3 of the joined body manufacturing apparatus 100 to form a joining guide WL in the overlapping portion of the joined members P is performed (step S102). The joining guide WL is formed on the same locus as the joining locus WA in the joined members P. The joining guide WL is concave or penetrating in the stacking direction of the joined members P from the surface of the joined body 1. In other words, the joining guide WL has a continuous groove-like or slit-like shape. The depth and width of the joining guide WL can be changed according to the type of the joining guide forming unit 3 used and the driving conditions.

[0026] Also, as shown in FIG. 4, in the present embodiment, the joining guide WL is in a solid line shape in the joining direction of the joined members P, but it may be, for example, in a broken line shape or a dotted line shape. Further, as shown in FIG. 5, it is preferable that the width of the joining guide WL is smaller than the outer diameter of the probe 22. At this time, even if the width of the joining guide WL is smaller than the outer diameter of the probe 22, since the outer diameter of the probe 22 has an inclined surface that inclines rearward from the tip portion near the center, the tip portion can enter the inside of the joining guide WL. Then, since a part of the inclined surface of the probe 22 contacts the upper portion of the inner wall of the joining guide WL, the probe 22 is guided by the joining guide WL. Even if the probe 22 rotates and frictional stirring occurs between the probe 22 and the joined member P, and a rotational vibration occurs in the friction stir joining tool 2, the probe 22 can be guided along the joining locus WA by such a guiding effect. In this way, since the width of the joining guide WL is smaller than the diameter of the probe 22, the meandering due to the rotational vibration of the friction stir joining tool 2 on the joined member P can be further suppressed.

[0027] Finally, as shown in FIG. 4, a step of joining the members to be joined P by friction stir welding is performed (step S103). The joining apparatus 100 moves the robot arm 5 and presses the rotating friction stir welding tool 2 against the joining guide WL on the members to be joined P formed in step S102. Then, the probe 22 penetrates into the members to be joined P by a predetermined length. Then, the joining apparatus 100 moves the robot arm 5 to move the friction stir welding tool 2 along the joining guide WL. At this time, the contact portion of the members to be joined P with the probe 22 plastically flows due to the rotation of the probe 22 and the frictional heat generated by the rotation. Then, the probe 22 stirs the plastically flowed portion of the members to be joined P to form a joining locus WA. The members to be joined P are joined to each other as the metal of this joining locus WA cools and hardens. When the friction stir welding is completed, the friction stir welding tool 2 is separated from the members to be joined P.

[0028] When the joining apparatus 100 moves while pressing the rotating friction stir welding tool 2 against the joining guide WL of the members to be joined P, the probe 22 is guided by the joining guide WL formed in step S102, so that meandering due to the rotational deviation of the friction stir welding tool 2 can be suppressed. Therefore, the joining apparatus 100 can advance the joining tool accurately.

[0029] In the friction stir welding in step S103, in order to improve the working efficiency, it is necessary to increase the moving speed of the friction stir welding tool 2 on the workpiece P. However, when the moving speed of the friction stir welding tool 2 is increased, the rotational deviation of the friction stir welding tool 2 becomes large. Therefore, in step S103, it is preferable to perform friction stir welding in a state where the temperature around the joining guide WL of the workpiece P is 200°C or higher. When the temperature of the workpiece P is 200°C or higher, the metallic workpiece P becomes soft. Therefore, the deformation resistance of the workpiece P becomes small, and even if the moving speed of the friction stir welding tool 2 is increased on the workpiece P, the rotational deviation of the friction stir welding tool 2 can be suppressed. Therefore, by performing friction stir welding in step S103 in a state where the temperature of the workpiece P is 200°C or higher, friction stir welding can be accurately and efficiently performed.

[0030] As a method of performing friction stir welding in step S103 in a state where the temperature of the workpiece P is 200°C or higher, for example, in step S102, there is a method of forming the joining guide WL while heating the workpiece P by a method involving heating the workpiece to be processed, such as plasma cutting, laser cutting, or gas cutting. In this method, after forming the joining guide WL while heating the workpiece P, step S103 is executed before the temperature around the joining guide WL of the workpiece P reaches 200°C. On the other hand, when the joining guide WL is formed in step S102 by a method that does not involve heating the workpiece to be processed, in step S103, the workpiece P may be heated using a heating device such as a heater, and friction stir welding may be performed in a state where the temperature of the workpiece P is 200°C or higher. less than As described above, according to the method for manufacturing a joined body according to the present embodiment, since the joining guide WL is formed on the joining locus WA of the workpiece P before joining and then friction stirring is executed, rotational wobbling of the friction stir welding tool 2 can be prevented. For this reason, without increasing the cost, rotational deviation of the friction stir welding tool can be suppressed, and the friction stir welding tool can be accurately moved.

[0031] As described above, according to the method for manufacturing a joined body according to the present embodiment, since the joining guide WL is formed on the joining locus WA of the workpiece P before joining and then friction stirring is executed, rotational wobbling of the friction stir welding tool 2 can be prevented. For this reason, without increasing the cost, rotational deviation of the friction stir welding tool can be suppressed, and the friction stir welding tool can be accurately moved.

[0032] Note that the present invention is not limited to the above-described embodiments, and can be appropriately modified without departing from the gist thereof.

Explanation of Reference Numerals

[0033] 1 Joint body 2 Friction stir welding tool 3 Joint guide forming part 4 Control device 5 Robot arm 21 Tool body 22 Probe 100 Joint body manufacturing apparatus P Workpiece to be joined WA Welding locus WL Welding guide

Claims

1. A method for manufacturing a joined body in which joined members of metal laminated in two or more layers are joined by friction stir welding, comprising: a step of laminating the joined members so that at least a part of each of the joined members overlaps with each other; a step of forming a joining guide in a portion of the joined members to be joined; a step of pressing a friction stir welding tool against the joining guide and moving the tool along the joining guide to join the joined members by friction stir welding; and wherein the joining guide is concave or penetrating in the stacking direction of the joined members from the surface of the joined body, A method for manufacturing a joined body.

2. The step of forming the joining guide includes forming the joining guide while heating the joined members, The method for manufacturing a joined body according to Claim 1.

3. Friction stir welding is performed in a state where the temperature of the joining guide is 200°C or higher, The method for manufacturing a joined body according to Claim 1 or 2.

4. A joined body manufacturing apparatus for joining joined members of metal laminated in two or more layers by friction stir welding, comprising: a joining guide forming unit that forms a joining guide in a portion of the joined members to be joined; and a friction stir welding tool that presses against the joining guide and moves along the joining guide to join the joined members by friction stir welding, wherein the joining guide is concave or penetrating in the stacking direction of the joined members from the surface of the joined body, A joined body manufacturing apparatus.

5. The joining guide forming unit forms the joining guide while heating the joined members, The joined body manufacturing apparatus according to Claim 4.

Images