JP2000153374A - Friction stir welding device, friction stir welding tool, and friction stir welding structure - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide a friction stir welding apparatus, a welding tool thereof, a welding structure thereof, and a use which do not cause backwash failure. The present invention includes a rotary driving device, and a joining tool 1 driven by the rotary driving device and formed of a material harder than a workpiece, and the joining tool is connected to a joining portion of the workpiece. In a friction stir welding apparatus or tool that frictionally stirs and joins two workpieces by pressing and inserting while pressing and inserting while moving the workpiece, at the tip of the welding tool, the plastic flow with respect to the workpiece is performed. Is provided with stirring means. This device provides a specific bead shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction stir welding apparatus and a friction stir welding tool used for joining, for example, aluminum alloy materials and the like, a joining structure obtained therefrom, and applications.

[0002]

2. Description of the Related Art A friction stir welding apparatus of this kind, which has been generally employed, is provided with a welding tool made of a material substantially harder than a workpiece and having a hemispherical tip. The workpiece is rotated while being pressed and inserted into the joint of two workpieces, that is, moved along the joining direction to plastically flow the joint and perform solid-phase joining.
Such friction stir welding is generally applied to joining of abutting portions and overlapping portions of an aluminum alloy workpiece. In addition, as related to this kind of friction stir welding apparatus and friction stir welding tool, for example, Japanese Patent Publication No. 7-505090 or Japanese Patent Publication No. 7-525109 is mentioned.

[0003]

According to the friction stir welding apparatus thus formed, two members (plates) are arranged on a jig in abutting manner, and a joining tool is arranged along the abutting surface. Are joined by rotating and inserting, so that there is a certain gap (gap) between the tip of the joining tool and the jig, and there is a portion that does not flow plastically with this kind of conventional joining tool There was a case. That is,
As shown in FIG. 4, the conventional joining tool includes a pin 2 at the tip and a shoulder 3 having a larger diameter than the pin 2. In this joining tool 1, the tip of the pin 2 is hemispherical. In this case, the member between the tip of the pin 2 and the jig 10 does not sufficiently flow plastically, and as a result, the butting surface on the back side of the bead remains unjoined, and a backwash defect easily occurs. was there.

[0004] It is an object of the present invention to provide a friction stir welding apparatus, a welding tool, and a welding structure obtained by the friction stir welding apparatus, which do not cause backwash failure, and applications thereof.

[0005]

According to the present invention, there is provided a rotary driving device, and a joining tool driven by the rotary driving device and formed of a material harder than a workpiece. In a friction stir welding apparatus that presses and inserts the workpiece while rotating it in a joining section and relatively moves the workpiece in a joining direction, and the workpiece is friction stir welded, the welding tool is provided with the welding tool in relation to the workpiece. Stirring means for generating a plastic flow below the tip end face is provided, and the joining tool is provided with irregularities on the tip end face so as to cause the workpiece to flow plastically below the tip end face of the joining tool. The joining tool has a stirring means for generating a plastic flow flowing downward with respect to the workpiece, and the tip surface of the joining tool is formed as a flat surface; Characterized in that a concave or convex portion on a surface.

It is preferable that the concave portion or the convex portion is one of a knurled shape, an arc-shaped groove provided radially or an arc-shaped ridge, a spiral groove, or a spiral ridge.

The present invention relates to a friction stir welding tool for friction stir welding a workpiece by pressing and inserting a welding tool made of a material harder than the workpiece into a joint of the workpiece while rotating the tool. For the workpiece, it has a stirring means for generating a plastic flow below the distal end surface of the joining tool, the joining tool plastically flows below the distal end surface of the joining tool to the workpiece. Providing irregularities on the distal end surface, forming the distal end surface of the joining tool on a flat surface, and providing a concave portion or a convex portion on this flat surface, the joining tool is positioned downward with respect to the workpiece. It is characterized in that it has a stirring means for generating a flowing plastic flow, or the joining tool has a flat portion inclined at an end with respect to the rotation axis.

According to the present invention, in a joining structure joined by friction, a bead formed by the joining has a cross section perpendicular to the joining direction and the bead and the mother at a central portion between the front surface and the back surface of the bead. The angle of inclination of the interface with the material to the back surface is 60 to 80 degrees, preferably 65 to 75 degrees, and the bead formed by the joining has a cross-sectional shape perpendicular to the joining direction. The angle of inclination of the interface between the base material and the rise from the back surface of the bead to the back surface is 25 to 50 degrees, preferably 30 to 45 degrees, and the bead formed by the joining is formed of a joining tool. Due to the vertical movement, a wavy processing line composed of arc-shaped irregularities is formed on the surface side, and the number of the wavy lines has a length of 1 with respect to the direction of joining. It is 15 to 30 pieces per mm, preferably 15 to 25 pieces, and the bead formed by the above-mentioned bonding is one or more of oxide beads dispersed in the bead, or a plurality or all of them. Characterized by having a combination of

According to the present invention, there is provided a railway vehicle comprising a body made of an aluminum alloy and having a frictionally joined joint structure, wherein the joint structure comprises the joint structure described above.

[0010] The type of aluminum material is not limited, and is pure aluminum, Al-Cu (JIS2000).
Alloy, Al-Mn (JIS3000) alloy, Al-Si (JIS4000) alloy, Al-Mg (JIS5000) alloy,
Al-Mg-Si (JIS6000) alloy, Al-Zn-
Wrought materials such as Mg-based (JIS7000-based) alloys, pure aluminum-based, Al-Si-based alloys, Al-Mg-based alloys, Al-C
u-Si alloy, Al-Cu-Mg-Si alloy, Al
-It may be appropriately selected and used from JIS standard aluminum casting materials such as an Mg-Si alloy or the like depending on the application.

The dissimilar metal material is a metal material other than aluminum, and its type is not particularly limited.
An iron-based material such as a SUS material may be used, or a copper-based, titanium-based, or Mg-based material may be used.

The above-mentioned aluminum material and dissimilar metal material may be appropriately combined and joined. The most desirable combination of the joining members is particularly when used for a structural material such as a car body for a car or a railway car or a joint. , Al-Mg
It is desirable to use a combination of an Al-Mg-Si-based aluminum material and an iron-based material, and when it is used as a bonding material for electronic components, a JIS6000-based aluminum material and a copper-based material or a titanium-based material or a magnesium-based material are used. A combination is desirable, and when used for aircraft bonding materials, Al-C
A combination of an aluminum material made of a u-based alloy material or an Al-Zn-Mg-based alloy material and a dissimilar metal material made of a titanium-based material is desirable, and any of them can realize a bonded state having high strength and excellent appearance.

In addition, the present invention can be used for structures such as ships, elevators, and pressure vessels.

For joining an aluminum alloy having a thickness of the workpiece of 4 mm or more, the joining tool should be 850 rpm or more.
It can be rotated preferably at 100 to 3000 rpm and moved along the joining line at a speed of more than 240 mm per minute, preferably 300 to 1000 mm. 3000
At higher rotation speeds above rpm, about 300mm per second
It can be moved at a higher speed, but if the moving speed is too high, pores are formed along one side. In addition, the rotation speed can be suppressed to 300 rpm, and the movement speed can be correspondingly reduced. For a certain moving speed, aluminum silicon magnesium alloy (BS
6082), there is an acceptable rotational speed such as about 240 mm per minute, and a rotational speed of 440 to 850 rpm is preferred.

[0015]

FIG. 1 shows a welding tool 1 used in a friction stir welding apparatus according to the present invention.
FIG. 3A is a front view and FIG. FIG.
As shown in the figure, the pin 2 is a joint inserted into the article to be joined, has a cut surface inclined with respect to the rotation axis, and the cut surface has an elliptical flat surface because the pin 2 is rod-shaped, Slope 1
6. The inclined surface 16 is the rotation axis 1 of the welding tool 1
Is about 38 degrees in this embodiment. In the present invention, this angle of 30 to 80 degrees is effective for preventing backwash failure. Particularly, 35 to 60 degrees is preferable. In addition, the inclined surface 16 allows the tip of the pin 2 and a JISSUS30
Stirring which positively plastically flows the material to be joined between the jig 10 and the backing made of 4 is generated. Due to this plastic flow, the abutment surface on the back side of the bead is agitated and does not remain after the joining, so that it is possible to prevent a back ripple failure.

In the friction stir welding method according to the present embodiment, the welding tool 1 rotating at a high speed is brought into contact with the welding portion of the workpiece to generate frictional heat, and at the same time, the pin 2 of the welding tool 1 is inserted into the welding portion. By moving in the joining direction, a plastic flow is generated at the joining portion in a solid state without melting and joining is performed. Pin 2 is 4.0m long
m, outer diameter 6.0 mm, shoulder diameter 13.0 mm. The rotation speed is 1600 rpm and the joining speed is 400 mm / min. The joining tool 1 has the rotation axis within 5 degrees (preferably 2 to 4 degrees) in a direction opposite to the joining direction from the vertical position to the joining direction.
Can be tilted.

The shoulder 3 and the pin 2 of the joining tool 1 used in this embodiment are made of an integrated tool steel. As tool steel, carbon tool steel SK1 described in JIS standard
~ 7, high speed tool steel SKH2 ~ 57, alloy tool steel S
KS 1 to 95, SKD 1 to 6 and the like can be used. In particular, in this embodiment, SKD61 of alloy tool steel is used.

FIG. 2 is a perspective view of a friction stir welding apparatus during welding using the welding tool of the present embodiment. This figure shows a state in which the extruded sections 5 are being joined together by friction stir welding. The extruded profile 5 is composed of a plate 9 having a thickness of 4 mm and a T-shaped rib 8. The plurality of ribs 8 are arranged in the joining direction of the plate 9. The material of the extruded profile 5 is aluminum alloy containing 0.7% of Mg and 0.7% of Si according to JIS standard A.
6N01.

In the joining of the extruded members 5, the ends of the extruded members 5 are joined to each other as shown in the figure. Further, the joining surface 6 is fixed by a temporary attachment 20. This temporary attachment is performed by TIG welding. The extruded member 5 is arranged on a jig 10 and fixed by a clamp 19.

By fixing the extruded section 5 in this way, moving the welding tool 1 rotating at a high speed as described above along the joining surface 6 and generating frictional heat, and plastically flowing at the joint. Join. At this time, the welding tool 1 is connected to a rotation motor 22 having a variable rotation speed, and the gantry 18 is automatically moved at a constant speed. The joining tool 1 can be moved left and right by driving means, and the gantry 18 is
The top is moved by an automatic controller.

FIG. 3 is a perspective view of the friction stir welding method.
In the friction stir welding method, welding is performed by moving along a welding surface 6 while rotating a welding tool.

FIG. 4 is a cross-sectional view of the joint before joining. As for the shape of the joint, a trapezoidal thick plate portion 11 is provided near the joint surface 6 to increase the thickness of the joint portion. This is A6N0
1 is an age hardened alloy, and the strength after joining decreases.
A predetermined bonding strength is secured by increasing the thickness of the bonding portion.

FIG. 5 is a sectional view of the joint during the joining. The high-speed rotation of the welding tool 1 inserted into the welding surface 6 causes the plastic flow region 12 of the workpiece itself near the welding tool 1.
Is formed.

FIG. 6 shows a conventional joining tool shape. The joining tool 1 is constituted by a small-diameter pin 2 at the tip and a large-diameter shoulder 3. In the conventional joining tool 1, since the tip of the pin 2 has a hemispherical shape, the aluminum member between the tip of the pin 2 and the jig 10 does not sufficiently flow plastically. For this reason,
However, there is a problem that the abutment surface on the back side of the bead remains without being joined, so that an improper backwash is likely to occur.

FIG. 7 shows a six-fold microscope photograph of the cross section of the bead after joining by the conventional joining tool. In this photo, the back is the welding direction with respect to the paper surface, and the rotation of the welding tool is performed clockwise. The welding tool is tilted about 3 degrees so that a gap is created in the traveling direction with respect to the surface of the workpiece. They are joined. The upper part of the photograph is the front side where the joining tool is inserted, and the lower part is the back side.

Although not clear in the figure, a linear defect occurred on the back side of the bead.

As shown in the figure, the rising angle of the bead from the back surface was about 11 degrees with respect to the back surface, and the angle of the straight portion at the center of the bead thereafter was about 57 degrees. Further, white zigzag lines were observed in the bead, and the oxide film present on the surface of the material to be joined and the groove surface was caught in a continuous manner.

FIG. 8 is a 6 × microscopic photograph of a cross section of the bead after joining by the joining tool of the present invention shown in FIG. The joining conditions, materials, and plate thicknesses are the same as in FIG. In the present invention, the joining surface is agitated to the back side of the bead, and there is no defect on the back side of the bead.

When friction stir welding is applied to a large structure such as a railway vehicle structure, the accuracy shown in FIG. 7 may occur due to poor accuracy of the jig and the accuracy of copying the tool to the joining surface. . This defect causes a reduction in strength. By joining with the joining tool of the present invention, it is possible to perform good joining without generating defects on a large structure.

As shown in the figure, the rising angle of the bead from the back surface was about 38 degrees with respect to the back surface, and the angle of the straight portion at the center of the bead thereafter was about 68 degrees with respect to the back surface. Further, no continuous oxide film as shown in FIG. 7 was found in the bead, and the oxide film was dispersed in the bead in a granular form. Therefore, as is apparent from the present embodiment, the plastic flow at the welded portion at the tip end of the welding tool was actively generated, so that good welding was obtained also on the back side of the bead. The plastic flow width on the back side of the bead was about 3.5, which was larger than that of the conventional welding tool shown in FIG.

Further, the bead surface on the front side according to the present invention exhibited corrugated irregularities according to the diameter of the shoulder 3 of the joining tool, and the number of corrugations was 19 per 10 mm of joining length. The number of the waveforms is controlled by the rotation speed and the welding speed of the welding tool, and it is necessary to make the number of the waveforms appropriate.

Further, since the weld bead obtained in this embodiment is subjected to large plastic flow or agitation in the solid phase, finer crystal grains are formed than the base material, and a higher tensile strength than the base material is obtained. Can be

The joining tool 1 used in this embodiment has a shape in which the tip of the rod-shaped pin 2 is cut so as to have an elliptical flat surface at an angle intersecting with the spiral groove 13. Has an effect of causing a plastic flow in which the workpiece at the cut portion flows downward. As a result, the plastic flow reaches the joint on the back side of the workpiece, and the occurrence of joining defects on the back side bead can be eliminated. The plastic flow flowing downward plays a large role in forming a good back bead, and can obtain the above-described bead shape. The plastic flow in the downward flow can be changed by the angle formed by the cutting surface with respect to the rotation axis, and the plastic flow in the direction intersecting the circumferential surface of the pin 2 is compared with the conventional joining tool which is straight. As a result, a large plastic flow can be generated, so that better joining can be obtained.

Further, in the present embodiment, since the shoulder 3 is joined with the front side bead entering the joint surface at the above-mentioned angle at the front side bead width in this embodiment, the above-mentioned line is formed according to the diameter thereof. Its bead width is about 13.
5 mm, and burrs were slightly formed on both sides of the bead width. The amount of burr was less than about 0.5 mm in depth. The height of the burr varies depending on the inclination and the amount of pushing of the welding tool, but it is preferable to perform welding so that no burr is formed.

The bead width on the back side in this embodiment was approximately 9 mm in appearance, including the heat affected zone. From the cross section shown in FIG. 8 described above, the width in the plastic flow zone was about 4 mm and that in FIG. 7 was about 2 mm. Therefore, it is considered that 3 mm or more is necessary to obtain a defect-free joint as a back bead as described above. However, if it is too large, the width of the heat influence becomes large, and the strength is reduced. In addition, at the time of joining, a backing metal is required as reinforcement for the joining portion, but stainless steel is used. By using copper or a copper alloy in combination, the width of the HAZ can be reduced.

Embodiment 2 FIG. 9 shows the shape of a welding tool according to the present invention. The difference from FIG. 1 is that there is no bottom surface 23,
It has an inclined surface 16. The inclined surface 16 actively causes the aluminum member between the tip of the pin 2 and the jig 10 to generate the same plastic flow as in the first embodiment. Due to this plastic flow, the shape of the entire bead and the butted surface on the back side of the bead are formed in the same manner as described above. In particular, the abutment surface on the back surface is stirred and does not remain after joining, so that it is possible to prevent improper backwash.

Embodiment 3 FIG. 10 shows the shape of a welding tool according to the present invention. In this joining tool, the inclined surface 16 is inclined to the shoulder 3.
The inclined surface 16 allows the aluminum member between the tip of the pin 2 and the jig 10 to positively plastically flow as described above. Due to this plastic flow, the shape of the bead is the same as that described above, and the butting surface on the back side of the bead is agitated and does not remain after joining, so that it is possible to prevent a backwash defect.

Embodiment 4 FIGS. 11, 12 and 13 show the shape of a welding tool according to the present invention. These joining tools have a structure in which unevenness 17 is provided at the tip of the pin 2. The unevenness 17 allows the aluminum member between the tip of the pin 2 and the jig 10 to positively plastically flow. The plastic flow agitates the butted surface on the back side of the bead and does not remain after the joining, so that it is possible to prevent the imprint failure.

That is, in this embodiment, unevenness 17 for increasing the rotational frictional resistance between the workpiece and the welding tool is provided on the tip end surface of the welding tool. In this figure, irregularities 17
Is an example in which a projection is provided. That is, in this case, the tip of the small-diameter pin 2 of the joining tool is a flat surface, and the projection 15a is provided on the flat surface. The projection 15a is provided on a portion other than the axis of the pin 2, and a portion as close to the peripheral portion as possible is more effective for plastic flow.

With the joining tool formed in this way, the member between the tip of the pin 2 and the jig 10 is made efficient and the wide area is in a state of plastic flow due to the unevenness 17.
By this sufficient plastic flow, the bead shape is also the same, and the abutting surface on the back side of the bead is agitated, so that a non-plastic flow area does not remain after the joining, so that it is possible to prevent the backwash failure.

Embodiment 5 FIG. 14 shows the shape of a welding tool according to the present invention. This joining tool has a structure in which an arc-shaped convex portion 4 is provided on a pin 2. The convex portion 4 positively plastically flows the member between the tip of the pin 2 and the jig 10 as in the above-described embodiment. The plastic flow agitates the butted surface on the back side of the bead and does not remain after the joining, so that it is possible to prevent the imprint failure.

Embodiment 6 FIG. 15 shows another example. Also in this case, the tip of the small-diameter pin 2 is flat, and the spiral groove 1
3 are provided. The spiral groove 13 allows the pin 2
The member between the tip of the tool and the jig 10 is in an effective plastic flow state as in the above-described embodiment. Due to this plastic flow, the butting surface on the back side of the bead is agitated and does not remain after joining,
Uranami defects can be prevented.

Embodiment 7 FIG. 16 shows another example. Also in this case, the tip of the small-diameter pin 2 is formed on a flat surface, and an arc-shaped groove 14 is provided on the flat surface. Due to the arc-shaped groove 14, the member between the tip of the pin 2 and the jig 10 is positively plastically flown, and the same effect as in the above-described embodiment is obtained.

Embodiment 8 FIG. 17 shows another example. Also in this case, the tip of the small-diameter pin 2 is formed on a flat surface, and an arc-shaped convex portion 4 provided radially on the flat surface is provided. The arc-shaped projection 4 allows the tip of the pin 2 and the jig 1
The members between 0 and 0 are positively plastically flowed, and have the same effect as in the previous embodiment. Note that, in this case, the same effect can be obtained by using an arc-shaped groove instead of the arc-shaped convex portion 4.

Embodiment 9 FIG. 18 shows another example. Small diameter pin 2
Is flat, and knurled irregularities 17 are provided on the flat surface. The unevenness 17 causes the member between the tip of the pin 2 and the jig 10 to positively plastically flow. The plastic flow agitates the butted surface on the back side of the bead and does not remain after the joining, so that it is possible to prevent the imprint failure.

Embodiment 10 This embodiment is different from the joining tool 1 shown in Embodiment 1 in FIG.
It is a top view which shows the cylindrical shoulder for cutting shown in FIG. This plan view is a view of FIG. 20 as viewed from below, is ring-shaped, and is provided with three cutting blades 47. The cylindrical shoulder for cutting is inserted into the tip of the shoulder 3 of FIG. 1 and is fixed to a desired position of the shoulder 3 by a bolt through the screw hole 41.

FIG. 20 is a sectional view of a portion shown by a dashed line in FIG. 19, and the other portion is a front view as viewed from the side. The cutting blade 47 is inclined toward the center of the ring as shown in the figure, and the joining tool 1 rotates while being inclined with respect to the traveling direction as shown in the first embodiment. It has an angle corresponding to the inclination angle of the welding tool 1 so as to be flat on the welding surface, and further has a concave portion formed on the inner peripheral side.

In this embodiment, as in the first embodiment, Al
Alternatively, an Al alloy can be joined.

According to the present embodiment, the discharge member can be removed at the same time as the joining by inclining by the joining tool provided with the cylindrical shoulder for cutting or pressing, so that the cutting step after the joining can be omitted. .

Embodiment 11 FIG. 21 shows a 25 m-long, 0.5 m-wide aluminum alloy.
FIG. 3 is a perspective view of a butt welding of a workpiece 32 for a railway vehicle having a thickness of 4 mm, in which a fixing jig for a pin 2 is arranged on the side where the joining tool 1 is arranged and on the opposite side (on the back side of the welding surface) and welded. The fixing jig is arranged not only in front of the welding tool 1 on the back side of the welding but also behind it.

In this welding method, the workpiece 32 is fixed to the support base 36, and further, a support jig for supporting the workpiece on the side where the welding tool 1 is arranged and on the opposite side so as not to be deformed by the load of the welding tool 1. The tools 37 and 38 are arranged. In this case, the support jigs 37 and 38 are provided with a rotation mechanism. Further, the support jigs 37 and 38
It also has a structure that can automatically move up and down in conjunction with the vertical movement of the workpiece. The welding is performed by moving the rotating tool in the direction 5 while rotating in the 4 directions.

In the present embodiment, welding was performed while monitoring the welding conditions on the front and back sides of the welding by an electronic monitoring device using a CCD camera.

As described above, the frictional resistance between the workpiece and the support jig is reduced by the workpiece support jig provided with the rotation mechanism and the vertical movement mechanism. Therefore, even when the workpiece is long, it can be easily and stably fixed. Therefore, welding can be stabilized. Butt welding of aluminum alloy was performed. The shape of the joining tool and the welding conditions are the same as in Example 1, and the shape of the weld bead is also substantially the same. By this welding, a high-speed railway vehicle can be manufactured.

Embodiment 12 FIG. 22 shows a welding method in which a joining tool 1 is arranged on both front and back surfaces of a workpiece 32 and welded from both front and back surfaces in a butt welding of a work made of the above-described aluminum alloy as an aluminum alloy for a vehicle. FIG. In the present embodiment, the joining tool 1 is arranged on the opposite side (the back side of the weld) of the workpiece, and further,
It is characterized in that the fixing jig is also arranged on the rear side of the rotary tool with respect to the welding direction.

The joining tool 1b is also arranged on the back surface of the welded portion, and has a structure in which the load of the joining tool 1a arranged on the front side is received by the joining tool 1b. In this welding method, first, the workpiece 32 is supported by the support base 36. With only this support, the workpiece 32 is deformed by the load of the joining tool and cannot be stably welded. For this reason, a total of four fixing jigs 37 and 38 for fixing the workpiece are arranged on the side where the joining tool 1 is arranged and on the opposite side so as not to be deformed by the load of the joining tool 1. In this case, the fixing jig 37
And 38 are provided with a rotation mechanism. Further, as shown in FIG.
And a structure capable of automatically moving up and down in conjunction with the vertical movement of the workpiece 32. In addition, the fixing jigs 37 and 38 provided with the rotating mechanism are used for the joining tool 1.
It moves in conjunction with the movement in the welding direction.

The joining tool 1 is attached to the motor 40,
Weld while moving at high speed.

As shown in the figure, the feature of the present embodiment is that the thickness of the welded portion of the workpiece is locally increased by 0.8 mm. Accordingly, even when a dent is formed on the surface of the welded portion due to friction between the rotating tool and the processed portion, the welded portion is thickened, so that a decrease in mechanical strength can be prevented.

As described above, the frictional resistance between the workpiece and the fixing jig is reduced by the workpiece fixing jig provided with the rotation mechanism and the vertical movement mechanism. For this reason, even if the workpiece is long and large like a railway vehicle, it can be easily and stably fixed. Therefore, a long workpiece such as a vehicle can be stably welded. The shape of the joining tool and the welding conditions are the same as in the first embodiment. By this welding, a vehicle for a high-speed railway was manufactured.

Embodiment 13 FIG. 23 is a sectional view showing a method of welding a honeycomb panel (hollow mold member) of a railway vehicle made of an aluminum alloy shown in Embodiment 1 manufactured by extrusion. This honeycomb panel has a length of 25 m and a width of 0.1 mm.
4 m, 50 mm thick. This honeycomb panel includes a face plate 42, a core material 43, and a rim material 44.
The honeycomb panel is arranged on a support base 36 and further fixed by fixing jigs 37 and 38 from above and below. In welding, the joining tool 1 is inserted into the joining portion of the rim member 44, and the workpieces are solid-phase joined from both surfaces. That is, since the present welding method does not melt, the molten metal does not drip downward due to the gravity of the molten metal. For this reason, welding was performed by inserting the joining tool 1 from above and below into the joining surface 6 of the honeycomb panel. The joining tool 1 is attached to the screw hole 41, moves in the direction of the welding line while rotating by the driving force of the motor 40, and performs solid-phase joining of the workpieces. The movement of the joining tool 1 can be automatically controlled in the vertical direction according to the deformation of the workpiece surface. Further, the joining tool 1 can be automatically controlled to move in the left-right direction along the welding line. This embodiment is characterized in that the height of the face plate at the joint is locally higher than the other portions by about 0.8 mm. Accordingly, even when a dent is generated on the surface of the welded portion due to friction between the joining tool and the processed portion, the welded portion is thickened, so that a decrease in mechanical strength can be prevented.

FIG. 24 is a perspective view of a railway vehicle structure manufactured by the above method. Part of the joint length is 12.
5 m 2, but a maximum length of 25 m is formed from the front and back surfaces. The shape of the welding tool and the welding conditions differed depending on the thickness of the welded portion, but the formation of the beads was the same as in Example 1.

[0061]

According to the present invention, a friction stir welding apparatus, a welding tool, a joining structure obtained by the friction stir welding apparatus, and various uses using the same can be achieved. An excellent effect of being obtained is obtained.

[Brief description of the drawings]

FIG. 1 shows the shape of a welding tool according to the present invention.

FIG. 2 shows a perspective view of a friction stir welding apparatus during welding.

FIG. 3 shows a perspective view of a friction stir welding method.

FIG. 4 shows a cross-sectional view of a joint before joining.

FIG. 5 shows a cross-sectional view of a joint during joining.

FIG. 6 shows the shape of a conventional welding tool.

FIG. 7 shows a micrograph of a cross section of a bead after joining by a conventional joining tool.

FIG. 8 shows a micrograph of a cross section of a bead after joining by the joining tool of the present invention.

FIG. 9 shows the shape of the welding tool of the present invention.

FIG. 10 shows the shape of the joining tool of the present invention.

FIG. 11 shows the shape of the joining tool of the present invention.

FIG. 12 shows the shape of the welding tool of the present invention.

FIG. 13 shows the shape of the welding tool of the present invention.

FIG. 14 shows the shape of the welding tool of the present invention.

FIG. 15 is a side view, a plan view, and a sectional view showing a welding tool according to the present invention.

FIG. 16 is a side view, a plan view, and a sectional view showing a welding tool according to the present invention.

FIG. 17 is a side view, a plan view, and a sectional view showing a welding tool according to the present invention.

FIG. 18 is a side view and a plan view showing a welding tool of the present invention.

FIG. 19 is a plan view of a cylindrical shoulder for cutting.

FIG. 20 is a sectional view of FIG. 19;

FIG. 21 is a perspective view of a friction welding device for a railway vehicle structure.

FIG. 22 is a cross-sectional view of a friction welding device for joining a railway vehicle structure from both sides.

FIG. 23 is a perspective view of a friction joining device for joining a railway vehicle structure from both sides.

FIG. 24 is a perspective view of a railway vehicle friction-joined.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Joining tool, 2 ... Pin, 3 ... Shoulder, 4 ... Convex part, 5 ... Extruded profile, 6 ... Joining surface, 7 ... Bead, 8 ... Rib, 9 ... Board, 10 ... Jig, 11 ... Thick board Part, 12: plastic flow region, 13: spiral groove, 14: arc-shaped groove, 15: friction coefficient increasing means, 15a: projection, 16: inclined surface, 17: unevenness, 18: gantry, 19: clamp, 20: temporary Attachment, 21: guide rail, 22: rotary motor, 23: bottom surface, 41: screw hole, 47: cutting blade.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masao Funao 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd. Hitachi Research Laboratory, Ltd. No. 1 F term in Hitachi Research Laboratory, Hitachi, Ltd. (Reference) 4E067 AA05 BG02 CA01 CA04 EA00 EA08

Claims (16)

[Claims] 1. A rotary driving device, comprising: a joining tool driven by the rotating driving device and formed of a material harder than a workpiece; and rotating the joining tool to a joining portion of the workpiece. In a friction stir welding apparatus for performing friction stir welding of the workpiece while pressing and inserting to relatively move the workpiece in the welding direction, the welding tool is configured to plastically flow below the tip end surface of the welding tool with respect to the workpiece. A friction stir welding apparatus, which is provided with a stirring means for causing the friction stir welding. 2. A rotary driving device, and a joining tool driven by the rotary driving device and formed of a material harder than the workpiece, the joining tool being rotated to a joining portion of the workpiece. In a friction stir welding apparatus that frictionally stirs and welds the workpiece while pressing and inserting while relatively moving in the welding direction, the welding tool causes the workpiece to flow plastically below the distal end surface of the welding tool. A friction stir welding apparatus characterized in that irregularities are provided on the front end surface. 3. A rotary drive device, and a joining tool driven by the rotary drive device and formed of a material harder than the workpiece, the joining tool being rotated to a joining portion of the workpiece. In the friction stir welding apparatus for friction stir welding the workpiece while pressing and inserting while relatively moving in the welding direction, the tip surface of the welding tool is formed on a flat surface, and a concave or convex portion is formed on the flat surface. A friction stir welding apparatus characterized in that a portion is provided. 4. A knurled shape, a radially provided arcuate groove or an arcuate ridge, a spiral groove, a spiral ridge, or a spiral ridge. Friction stir welding equipment. 5. A rotary drive device, and a joining tool driven by the rotary drive device and formed of a material harder than the workpiece, wherein the joining tool is rotated to a processing portion of the workpiece. In a friction stir welding apparatus configured to press-insert and relatively move in the welding direction and friction stir weld the workpiece, the welding tool has a flat part inclined at an end thereof with respect to a rotation axis of the tool. A friction stir welding apparatus comprising: 6. A rotary drive device, and a joining tool driven by the rotary drive device and formed of a material harder than the workpiece, and rotating the joining tool to a joining portion of the workpiece. In a friction stir welding apparatus for performing friction stir welding of the workpiece while pressing and inserting while relatively moving in the welding direction, the welding tool includes a stirrer for generating a plastic flow flowing downward to the workpiece. A friction stir welding apparatus comprising: 7. A friction stir welding tool that frictionally stirs a workpiece by pressing and inserting a welding tool made of a material harder than the workpiece into a joint portion of the workpiece while rotating the tool. A friction stir welding tool, comprising: a stirring means for causing a plastic flow to occur on a workpiece below a tip surface of the welding tool. 8. A welding tool formed of a material harder than the workpiece is pressed and inserted into the joining portion of the workpiece while being rotated and relatively moved in a welding direction, and the workpiece is friction stir welded. A friction stir welding tool, characterized in that the welding tool is provided with irregularities on the front end surface thereof so as to cause the workpiece to flow plastically below the front end surface of the welding tool. 9. A friction for stir-welding the workpiece while rotating and pressing the welding tool formed of a material harder than the workpiece into the joint of the workpiece and relatively moving the workpiece in the welding direction. A friction stir welding tool, characterized in that, in the stirring and welding tool, the distal end surface of the welding tool is formed as a flat surface, and the flat surface is provided with a concave portion or a convex portion. 10. A welding tool formed of a material harder than the workpiece is pressed and inserted into the processing portion of the workpiece while being rotated and relatively moved in the welding direction, and the workpiece is friction stir welded. In the friction stir welding tool thus constructed, the welding tool has a flat portion inclined with respect to a rotation axis at a tip end thereof. 11. A welding tool formed of a material harder than the workpiece is pressed and inserted into the joining portion of the workpiece while being rotated and relatively moved in the welding direction, and the workpiece is friction stir welded. Friction stir welding tool
A friction stir welding tool, characterized in that the welding tool has a stirring means for generating a plastic flow flowing downward to the workpiece. 12. In a friction-welded joining structure, a bead formed by the joining has a cross section perpendicular to the joining direction, and the bead and the base material at a central portion between the front surface and the back surface of the bead. Wherein the angle of inclination of the interface between them is 60 to 80 degrees. 13. A joint structure formed by friction joining, wherein a bead formed by the joining has a rising slope from a back surface of the bead at an interface between the bead and the base material in a cross section perpendicular to the joining direction. A joint structure having an angle of 25 to 50 degrees. 14. In a joining structure joined by friction, a bead formed by the joining is formed with a wave shape composed of arc-shaped irregularities on a surface side thereof, and the number of the wave shape is different from the traveling direction of the welding. A joint structure having 15 to 30 pieces per 10 mm in length. 15. A joint structure formed by friction joining, wherein a bead formed by the joining has oxide particles dispersed in the bead. 16. A railway vehicle having a vehicle body made of an aluminum alloy and made of a frictionally joined joint structure, wherein the joint structure comprises the joint structure according to any one of claims 12 to 15. And the railway car.