JP2003136258A - Friction stir welding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction stir welding method which suppresses the occurrence of defects. SOLUTION: The end of a face plate and the end of an edge material 520 are butted to each other. A piece 525 overlapping the back surface of the face plate 21 protrudes from the edge material 520. The edge material 520 has a projecting part 523 which protrudes outward. A rotary tool 50 is inserted from the projecting part 523 side and friction stir welding is performed. The rotative direction of the rotary tool 50 is rightward as seen from a large diameter part 51 side. The moving direction of the rotary tool 50 is directed to the back side as seen from the front side of a paper, and in the right side from the axial center of the rotary tool 50, fluidized metal has higher pressure. The overlapped surface between the face plate 21 and the projecting piece 525 exists on the fluidized metal having higher pressure. The projection part 523 is positioned on the left side of the axial center of the rotary tool 50. In such a manner, the production of a continuing oxidized film is suppressed and notch on the overlapped surface is suppressed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a friction stir welding method.

[0002]

2. Description of the Related Art In the friction stir welding method, a round bar (referred to as a rotary tool) inserted into a joint is rotated and moved along a joint line to heat the joint, soften it, and cause it to plastically flow.
This is a method of solid phase bonding. The rotary tool has a large diameter part and a small diameter part. The small diameter portion is inserted into the member to be joined, and the end surface of the large diameter portion is brought into contact with the member. Screws are provided on the small diameter part.

Further, a convex portion is provided on the rotary tool insertion side of the two members to be joined, the small diameter portion of the rotary tool is inserted into the abutting portion, and the large diameter portion of the rotary tool is inserted into the convex portion. Friction stir welding is performed. The metal of the convex portion is used as a raw material to fill the gap between the two members. The convex portion may be provided on only one member. This is used when a member is made of an extruded shape and friction stir welding is performed on a portion where the extruding directions are orthogonal to each other. These are shown in Patent Document 1.

[0004]

[Patent Document 1] Japanese Patent Application Laid-Open No. 11-90655 (USP
6050474)

[0005]

FIG. 8 is a vertical cross-sectional view of a friction stir welded portion of a butting portion of a member M1 having a convex portion P1 and a member M2 having no convex portion. Figure 8
(A) is a state in which the rotary tool 50 is inserted into the abutting portion of the two members M1 and M2. FIG. 8B is a vertical cross-sectional view after joining, and hatching indicates a stirring region. The stirring area is schematically shown. The rotary tool 50 for friction stir welding is
It is composed of a large diameter portion 51 and a small diameter portion 52 at its tip. At the time of friction stir welding, insert the small-diameter portion 52 into the abutting portion,
A part of the large diameter portion 51 is inserted into the convex portion P1. Small diameter part 5
The tip of 2 is inserted in the protruding piece P2 that overlaps the back surface of the member M2. The lower end of the large diameter portion 51 is positioned so as to contact the upper surface of the member M2. When bonded by this, as shown in FIG. 8B, a continuous oxide film A is generated near the surface of the bonded portion on the side of the member M2 having no convex portion. It is considered that this continuous oxide film A was not diffused because the oxide film on the surface of the member was caught. In addition, the protruding piece P2 and the member M2
The surface where and are overlapped is the upper surface side (the large diameter portion T1 side of the rotary tool T)
The raised notch B is likely to occur. It is considered that the continuous oxide film A and notch B reduce the strength.

An object of the present invention is to provide a friction stir welding method capable of suppressing the occurrence of defects.

[0007]

According to various studies, the pressure of the metal fluidized by the rotation of the rotary tool is not the same in all within the projection range in the axial direction of the rotary tool,
It is considered that the pressure varies depending on the position. It is considered that the position where the pressure is high is determined by the rotation direction and the movement direction of the rotary tool. As a result, continuous oxide film A and notch B
It is thought to lead to the occurrence of.

In the present invention, since the position where the pressure of the fluidized metal becomes high is determined from the rotation direction and the moving direction of the rotary tool, the member having no convex portion should be positioned at the position where this high pressure is generated. Is characterized by.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of the present invention is shown in FIGS.
Explained by. A vehicle body 500 of a railway vehicle includes a side structure 501 forming a side surface, a roof structure 502 forming a roof,
It is composed of an underframe 503 that constitutes the floor, and a gable structure 504 that constitutes the end portion in the longitudinal direction. Side structure 501, roof structure 502,
The underframe 504 includes a plurality of extruded frame members 10 and 20, respectively.
It is configured by joining. The longitudinal direction (extrusion direction) of the extruded frame members 10 and 20 is oriented in the longitudinal direction of the vehicle body 500. The extruded frame members 10 and 20 are hollow frame members made of aluminum alloy.

The side structure 501 has a plurality of windows 530,
Also, there is a doorway 510 for people. An edge member 520 is joined to the edge of the opening of the doorway 510. The edge member 520 is a high-strength member having a large wall thickness. The edge member 520 is an extruded shape member made of an aluminum alloy, and is bent in a U shape along the left and right sides and the upper side of the entrance 510.

Extruded frame member 1 constituting the side structure 501
The extrusion direction of 0 and 20 is the longitudinal direction of the vehicle body, that is, the side structure 501. Since the edge member 520 is also an extruded shape member,
At the left and right sides of the entrance 510, the extruding direction of the edge member 520 and the extruding direction of the shape members 10 and 20 are orthogonal to each other. The extruded frame members 10 and 20 are hollow frame members.

The hollow profile 10 (20) includes two face plates 11 (21) and 12 (22) that are substantially parallel to each other, and a plurality of connecting plates 13 (23) and 14 that connect the two face plates. (2
4) and

It is orthogonal to the connecting plate 14 (24) and the face plates 11, 12 (21, 22) at the widthwise ends of the hollow frame 10 (20). On the outer surface side of the connecting portion between the connecting plate 14 and the face plate 11 (12), there is a recess where the face plate 21 (22) of the hollow frame member 20 overlaps. At the end of the hollow frame 10, the hollow frame 2 is attached.
It overlaps with the face plates 21 and 22 of 0. At the ends of the face plates 11 and 22, there are protruding pieces 15 that support the face plates 21 and 22. Protruding piece 1
Reference numeral 5 projects from the connecting plate 14. The protruding piece 15 is connected to the recess.

At the ends of the face plates 11, 12 (21, 22), there are convex portions 17 (27) projecting to the outer surface side (outside in the thickness direction) of the hollow frame members 10, 20. The end faces of the face plates 11 and 21 and the convex portion 17 (that is, the concave face plates 11 and 12 side) are near the center of the thickness of the connecting plate 14. The end faces of the face plate 11 (12) and the convex portion 17 of the hollow frame member 10 and the end faces of the face plate 21 (22) and the convex portion 27 of the hollow frame member 20 are butted against each other.

The face plate 11 (12) and the face plate 21 (22) are on the same surface, and the protrusion margins of the convex portions 17 and 27 are the same. Two
The widths of the two convex portions 17 and 27 are the same. The width of the two convex portions is larger than the diameter of the large diameter portion 51 of the rotary tool 50. Convex part 1
The metals 7 and 27 serve as metal resources for filling the gap between the abutted portions.

As shown in FIG. 5, first, the shape members 10 and 20 will be described. Upon joining, the two hollow profiles 10, 2
0 is mounted on the pedestal 100 and fixed. The rotary tool 50 is provided with a small diameter portion 52 at the tip of the large diameter portion 51. The small diameter portion 52 is provided with a screw. At the time of joining, the rotary tool 50 is inserted into the butted portion. The lower end of the large diameter portion 51 is the convex portion 1
Located within 7, 27. The small-diameter portion 52 has face plates 11 and 21.
Put it in the butt part of. The lower end of the small diameter portion 52 has a protruding piece 1
Inserted a little in 5. While rotating the rotary tool 50, the rotary tool 50 is moved along the joining line of the butted portion. Convex part 1
7 and 27 are the resources for filling the gap between the butted parts. After the friction stir welding on the upper surface side of FIG.
Flip 0 and 20 upside down and perform friction stir welding in the same manner.

In this way, when all the hollow frame members 10 and 20 constituting the side structure 501 are joined, the interior of the vehicle is turned up and unnecessary portions around the openings of the window 530 and the doorway 510 can be cut. Remove. Outer face plate 21 (1
The end of 1) is the face plate 22 (12) and the connection plate 23 on the inside of the vehicle.
It projects toward the opening side from the end of (24, 13, 14). Next, the side structure 510 processed as described above is placed on the edge member 520 that is bent in a U shape.

Next, the edge member 520 of the entrance 510 is friction stir welded to the hollow members 10, 20. In FIG. 1, U
A curled edging 520 is placed in the opening for the doorway 510. The edge member 520 includes a piece 521 that closes the ends of the hollow frame members 10 and 20, a convex portion 523 that projects outward from the outer surface of the face plate 21 (11) outside the vehicle, and a face plate 21 (11).
And the outer surface 2 of the face plate on the inside of the vehicle.
2 (12) and a protruding piece 527 that overlaps. Convex portion 52
The end surface on the vehicle outer side of the piece 521 except for 3 is substantially flush with the outer surface of the face plate 21 (11). The protruding piece 525 on the outer side of the vehicle is located at a position recessed from the outer side of the vehicle. The end of the face plate 21 (11) is butted against the edge member 520.

This butt portion is friction stir welded from above. The edge member 520 is fixed to the pedestal 100. Since the end portions of the face plates 21 and 11 that are abutted with the edge member 520 are the end portions in the extrusion direction, the face plate 11 and 21 have convex portions 1
There is no 7 or 27. Since the hollow shape member 10 in contact with the central piece 520C of the U-shaped edge member 520 has the end in the width direction cut, there is no protrusion.

Next, the abutting portion of the face plate 21 (11) and the edge member 520 is friction stir welded from above. Rotating tool 5
The small diameter portion 52 of 0 is inserted into the abutting portion. Small diameter part 52
The tip of the is inserted into the protruding piece 525. A part of the large diameter portion 51 enters the convex portion 523. Lower end of large diameter portion 51 and face plate 21
Insert so that there is a slight gap between it and the upper surface of (11). Since the rotary tool 50 is inserted with the large diameter portion 51 side inclined rearward with respect to the moving direction, there is a gap between the lowermost end of the large diameter portion 51 and the upper surface of the face plate 21 (11).

After inserting the rotary tool 50 into the portion to be joined as described above, the rotary tool 50 is rotated and moved along the joining line. In FIG. 1, it is moved from the front side of the paper surface toward the back side of the paper surface. In FIG. 2, which is a plan view of FIG. 1, Y is the moving direction of the rotary tool 50, and R is the rotating direction of the rotary tool 50. The screw of the small diameter portion 52 is a left screw. From the large diameter portion 51 side of the rotary tool 50 to the small diameter portion 5
When viewing the 2 side, the rotation direction of the rotary tool 50 is right (clockwise). When looking forward from the rotary tool 50 in the moving direction, as shown in FIG. 1, the convex portion 527 is on the left side of the axis of the rotary tool 50, and the protruding piece 523 is on the right side. The rotation center of the rotary tool 50 is inclined. The axial center of the large diameter portion 51 is located rearward of the axial center of the small diameter portion 52 in the moving direction.

In FIG. 4, the rotary tool 50 first has a U
The right edge 520R of the strip-shaped edge member 520 is inserted into the abutting portion of the lower end of the right edge 520R, and the movement is started from here. The rotary tool 50 moves from the right piece 520R toward the central piece 520C,
The central piece 520C moves to the left piece 520L. Finally, the lower end of the left piece 520L is reached and the joining is completed.

In the friction stir welding, the metal of the convex portion 523 is moved to the upper surface side of the face plate 21 (11) and also serves as a resource for filling the gap between the face plate 21 (11) and the edge member 520.

After the friction stir welding, the convex portion 523 and the joint portion above the outer surface of the face plate 21 (11) are cut with a grinder. After or before the friction stir welding, the protruding piece 527 and the face plate 22 (12) are fillet welded.

According to this, as shown in FIG. 3, the continuous oxide film A which has conventionally been generated in the vicinity of the upper surface of the bonding portion is reduced or eliminated. Further, the notch B generated in the overlapping surface of the protruding piece 525 and the face plate 21 (12) becomes smaller or disappears. The hatching in FIG. 3 indicates the stirring area. The stirring area is schematically shown.

It is considered that the pressure of the metal in the joint fluidized by the rotary tool 50 is greater on the right side than the axial center of the rotary tool 50 than on the left side in the moving direction of the rotary tool 50. This is because the rotary tool 50 is rotating to the right,
It is considered that unbonded metal in front of the rotary tool 50 is moved to the right side. As a result, it is considered that the continuous oxide film A decreases or disappears even if there is a joint portion with the face plate 21 (11) on the right side. Also,
Even if there is a lap surface on the right side, it is considered that the notch B is reduced or eliminated in the lap surface.

On the other hand, the pressure on the left side of the rotary tool 50 is lower than that on the right side. This is presumably because there is no unbonded metal behind the rotary tool 50, and no new metal is supplied to the left side. Therefore, it is considered that the continuous oxide film A is reduced or eliminated on the left side. Also, there is no overlapping surface on the left side.

When the screw of the small diameter portion 52 is a right screw, the rotation direction is left (counterclockwise). In this case, the high pressure portion is generated on the left side of the axis when the moving direction is seen from the rotary tool 50. Therefore, the left side has the overlapping surface and the right side has the convex portion 527. That is, the left piece 5 of the edge member 520
The rotary tool 50 is moved from 20L to the right piece 520R through the central piece 520C.

The embodiment shown in FIG. 7 will be described. A convex portion 123 is projected on the surface side of the end portion of the plate 111. A projecting piece 125 projects from the tip of the convex portion 123 in parallel with the plate 121. A projecting piece 127 projects parallel to the projecting piece 125 on the back side of the plate 121. The plate 131 has two protruding pieces 12
It enters between 5,127 and is abutted against the plate 121. The end of the face plate 121 and the end of the face plate 111 are butted against each other. The lower end of the large diameter portion 51 of the rotary tool 50 is located inside the convex portion 123 and the protruding piece 125. In the embodiment of FIG. 7, the protruding pieces 125 and 127 may be omitted. Protruding piece 1
Excluding 27 only suppresses the generation of a continuous oxide film.

The technical scope of the present invention is not limited to the wording described in each claim of the claims or the wording described in the section of means for solving the problem, and can be easily replaced by those skilled in the art. It extends to a range.

[0031]

According to the present invention, friction stir welding capable of suppressing the generation of defects can be performed.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view during joining of a rim member and a hollow member according to an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a vertical cross-sectional view after joining in FIG.

FIG. 4 is a front view of a side structure according to an embodiment of the present invention.

5 is a sectional view taken along line VV of FIG.

FIG. 6 is a perspective view of a vehicle body of a railway vehicle.

FIG. 7 is a vertical cross-sectional view of a joint portion according to another embodiment of the present invention.

FIG. 8 is a vertical cross-sectional view of a conventional joint portion.

[Explanation of symbols]

10, 20: Hollow profile, 11, 12, 21, 22: Face plate, 50: Rotating tool, 51: Small diameter part, 52: Large diameter part, 5
10: Doorway, 520: Edge material, 523: Convex portion, 12
1, 131: plate, 123: grain, 125, 127 protruding piece, 525, 527, protruding piece, Y: moving direction of rotating tool 50, R: rotating direction of rotating tool 50

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazunari Fukuyori             Hitachi-Kasa, 794 Higashi-Toyoi, Kudamatsu City, Yamaguchi Prefecture             Inside Toki Kogyo Co., Ltd. F term (reference) 4E067 AA05 BG00 DA13 DA17 DC07                       EA08 EC03

Claims (10)

[Claims] 1. An end portion of a first plate and an end portion of a second plate are abutted with each other, and the abutted end portion of the first plate is a protrusion protruding from one surface in a thickness direction of the plate. And the convex portion is the second
Of the plate of the large diameter portion, using a rotary tool having a small diameter portion at the tip of the large diameter portion, when inserting the small diameter portion into the butted portion and performing friction stir welding, When a part is inserted into the convex portion and viewed from the large-diameter portion side, while rotating the rotary tool rightward, the rotary tool is relatively moved along the abutted portion, and when viewed in the moving direction. Friction stir welding, wherein the second plate is positioned on the right side of the axis of the rotary tool, and the convex portion is positioned on the left side of the axis of the rotary tool. Method. 2. The friction stir welding method according to claim 1, wherein the second plate is projected from the other surface of the end portion of the first plate substantially in parallel with the second plate. When having a protruding piece, when viewed from the large diameter portion side, the protruding piece overlaps the back surface of the end portion of the second plate, and inserts a part of the tip of the small diameter portion into the protruding piece. Friction stir welding in the state described above. 3. The friction stir welding method according to claim 1,
Each of the first plate and the second plate is an extruded frame member, and the extrusion direction of the second extruded frame member is substantially orthogonal to the extrusion direction of the first extruded frame member. And the friction stir welding is performed in such a state. 4. An end portion of a first plate and an end portion of a second plate are abutted against each other, and the abutted end portion of the first plate is a protrusion protruding from one surface in a thickness direction of the plate. And the convex portion is the second
Of the plate of the large diameter portion, using a rotary tool having a small diameter portion at the tip of the large diameter portion, when inserting the small diameter portion into the butted portion and performing friction stir welding, When a part is inserted into the convex portion and viewed from the large diameter portion side, the rotary tool is relatively rotated along the abutted portion while rotating the rotary tool counterclockwise, and viewed from the direction of the movement. The second plate is positioned on the left side of the axis of the rotary tool, and the protrusion is positioned on the right side of the axis of the rotary tool. . 5. The friction stir welding method according to claim 4, wherein the second plate is projected substantially parallel to the second plate from the other surface of the end portion of the first plate. When having a protruding piece, when viewed from the large diameter portion side, the protruding piece overlaps the back surface of the end portion of the second plate, and inserts a part of the tip of the small diameter portion into the protruding piece. Friction stir welding in the state described above. 6. The friction stir welding method according to claim 4,
Each of the first plate and the second plate is an extruded frame member, and the extrusion direction of the second extruded frame member is substantially orthogonal to the extrusion direction of the first extruded frame member. And the friction stir welding is performed in such a state. 7. An end portion of the first extruded frame member and an end portion of the second extruded frame member are butted against each other, and the first extruded frame member and the second extruded frame member form a side structure of a railway vehicle. The first extruded frame member is a member that constitutes the edge of the opening, and the first extruded frame member has a convex portion protruding outward from one surface of the first extruded frame member and the other surface thereof. A projecting piece that projects substantially parallel to the second extruded profile, and the end of the second extruded profile is superposed on the projecting piece, and the tip of the large-diameter section is formed. In using a rotary tool having a small diameter portion to insert the small diameter portion into the butted portion and perform friction stir welding, insert a portion of the large diameter portion into the convex portion, and see from the large diameter portion side. When the rotating tool is rotated clockwise, And the second extruded profile member and the protruding piece are located on the right side of the axis of the rotary tool and on the left side of the axis of the rotary tool when viewed in the moving direction. A method of manufacturing a railway vehicle, wherein the convex portion is located, and a part of a tip of the small diameter portion is inserted into the protruding piece. 8. The method of manufacturing a railway vehicle according to claim 7, wherein the edge member is formed of at least three of the first extruded frame members.
A method for manufacturing a railway vehicle, which is bent so as to have a side, and when viewed from the outside of the car, the rotary tool is sequentially moved from the right side to the center side and the left side of the edge material. . 9. An end portion of the first extruded frame member and an end portion of the second extruded frame member are butted against each other, and the first extruded frame member and the second extruded frame member are side structures of a railway vehicle. The first extruded frame member is a member that constitutes the edge of the opening, and the first extruded frame member has a convex portion protruding outward from one surface of the first extruded frame member and the other surface thereof. A projecting piece that projects substantially parallel to the second extruded profile, and a plate of the second extruded profile is superposed on the projecting piece, and a small diameter is provided at the tip of the large diameter part. Using a rotary tool having a portion, when inserting the small diameter portion into the butted portion and performing friction stir welding, part of the large diameter portion is inserted into the convex portion, when viewed from the large diameter portion side. , Rotate the rotary tool counterclockwise and move relatively along the abutted part With it, when viewed in the moving direction, the second extruded shape member and the protruding piece are positioned on the left side of the axis of the rotary tool, and on the right side of the axis of the rotary tool, A method for manufacturing a railway vehicle, wherein a convex portion is located, and a part of the tip of the small diameter portion is inserted into the protruding piece. 10. The method for manufacturing a railway vehicle according to claim 9, wherein the edge member is formed of at least three of the first extruded frame members.
A method for manufacturing a railway vehicle, characterized in that the rolling tool is bent so as to have a side, and when viewed from the outside of the car, the rotary tool is sequentially moved from the left side of the edge material toward the center side and the right side .