JPH10296462A - Method for friction stirring welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of improving joint efficiency as well as preventing generation of misalignment and further minimizing deformation due to bonding. SOLUTION: A rotating probe 12 is inserted into the butt part of two sheets of plate-phased jointing members 1, 2, and by relatively sifting the probe 12 along the butt part in a inserted state while softening and stirring the part contacting the prove 12 with frictional heat, the joining members 1, 2 are butt joined with each other. At this time, joining part pressing rollers 20, 21 are arranged which travel rolling over the butt part 3 on the joining members 1, 2 each located in front and in the rear of the probe 12 in the direction of proceeding of the probe 12, and by these pressing rollers 20, 21 in front and in the rear, both of the joining members 1, 2 are pressed on the front and rear side, and the right and left sides of the prove 12.

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 method used for joining plate-shaped joining members made of a metal material such as an aluminum material.

[0002] In this specification, the term "aluminum" is used to include its alloy.

[0003]

2. Description of the Related Art The following method has been proposed as a friction stir welding method, which is one of the solid-state welding methods. That is, FIG.
As shown in (1), a small-diameter pin-shaped probe (112) that is harder than the joining members (101) and (102) is provided integrally on the end axis of the large-diameter cylindrical rotor (111). Rotor (111) using the joining device (110)
Is rotated at a high speed, and the probe (112) is inserted into or near the butted portion (103) of the two joined plate-shaped joining members (101) and (102). Insertion is
Generally, the process is performed until the shoulder (111a) formed of the probe-side flat surface of the rotor (111) comes into contact with the joining members (101) and (102). Then, the probe (112) is moved relative to the joining members (101) and (102) along the butting portion (103) with the probe inserted. The frictional heat generated by the rotation of the probe (112) or the frictional heat generated by the sliding between the shoulder (111a) of the rotor (111) and the joining member causes the probe (1
12) Near the contact portion with the joining member (101)
The probe (102) is softened and agitated by the probe, and the probe (112) is moved so that the softened and agitated portion receives the advance pressure of the probe (112) and fills the passage groove of the probe with the movement of the probe (112). After flowing plastically in such a manner as to wrap backward in the direction of travel, the heat of friction is rapidly lost and the solidified material is cooled and solidified. This phenomenon is the probe (112)
The joining members (101) and (102) are finally joined at the butt portion (103). Further, such a friction stir welding method is used for lap welding as well as butt welding as shown in FIG.

According to such friction stir welding, since it is a solid phase welding, there is no restriction on the type of metal material used as the joining members (101) and (102). Therefore, there is an advantage that deformation due to thermal distortion at the time of joining is small.

[0005]

The joining member (1)
01) (102) In particular, a thin and long joining member may not be flat because it is warped or twisted in the thickness direction. When they are butted using such joining members (101) and (102), a step due to warping and a gap due to twisting are generated in the butted portion (103). A problem arises in that a difference is made or joint efficiency is reduced. In particular, since the friction stir welding is a solid-phase welding, the joint efficiency is significantly reduced even if the gap generated in the butt portion (103) is small. In addition, when joining thin and long joining members even in the case of friction stir welding, deformation tends to occur and it is difficult to obtain a high-quality joined product.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and can prevent the occurrence of misalignment, improve the joint efficiency, and join thin and long joining members. It is an object of the present invention to provide a friction stir welding method capable of reducing deformation even in such a case.

[0007]

In order to achieve the above object, a first aspect of the present invention is to insert a rotating probe into a butt portion or an overlap portion between two plate-like joining members or in the vicinity thereof, While softening and stirring the contact portion with the frictional heat by the frictional heat, the probe is relatively moved along the butt portion or the overlapping portion in the inserted state, so that the joining members are butt-joined or overlap-joined. In the joining method, on both joining members, before and after the moving direction of the probe, a joining member pressing roller that moves while rolling the butting portion or the overlapping portion in the direction in which the probe moves is disposed, and The friction stir welding is performed while holding both front and rear sides of the probe of the both joining members by the pressing roller.

[0010] According to this, both the joining members are pressed by the front and rear pressing rollers on both front and rear sides of the probe, and the warp and twist are corrected to be flat between the front and rear pressing rollers, so that the contact area of the both joining members increases. As a result, joint efficiency is improved. In addition, since the two joining members are joined in a flat state between the front and rear pressing rollers, misalignment can be prevented. In addition, since the two joining members are joined under the restrained state in which the front and rear sides of the probe are pressed by the front and rear pressing rollers, distortion due to joining is suppressed, and deformation of the joining member is reduced.

According to a second aspect of the present invention, in the friction stir welding method according to the first aspect, the moving speed of the front and rear pressing rollers is relatively higher in the front pressing roller than in the rear pressing roller. By performing such control, friction stir welding is performed while applying tension in the tensile direction to the butting portion or the overlapping portion between the front and rear pressing rollers.

According to this, the two joining members are further flattened by the tension in the tensile direction, the contact area between the two joining members is increased, and the joint efficiency is further improved. In addition, the strain caused by the joining is absorbed by the tension in the tensile direction, and the deformation of the joining member is significantly reduced. Thus, when absorbing the joining strain, even when adopting a configuration in which tension is applied in the tensile direction from both ends of both joining members,
Bonding distortion can be absorbed. However, in this case, when both joining members are long, a large-sized device is required to generate the tensile tension, and there is a practical difficulty. On the other hand, according to the second aspect, since the pressing rollers before and after generating the tension move on both the joining members, the length of the joining member is not limited, and the length of the joining member is long. Even in this case, the joining strain can be easily absorbed.

[0011]

1 and 2 relate to one embodiment of the present invention. In these figures, (1)
(2) are two thin and long aluminum plate-like joining members having the same thickness and arranged in the same plane with one end surfaces in the width direction abutting each other. These joining members (1)
(2) is mounted on a joining member mounting table (not shown). Then, as shown in FIG. 2, since undulation-like warpage and small twist are generated in the thickness direction, the butt portion (3)
In this state, a step (4) due to warpage and a small gap (not shown) due to torsion are generated.

Reference numeral (10) denotes a joining device, in which a small-diameter pin-shaped probe (12) is provided integrally on the end axis of a large-diameter cylindrical rotor (11). By rotating the probe (11), the probe (12) can also be rotated. The probe (1
2) and the rotor (11) are formed of a heat-resistant material that is harder than the joining members (1) and (2) and that can withstand frictional heat generated during joining.

(20) and (21) are rotatable joining member pressing rollers having a moving mechanism and a pressing mechanism (not shown) having the same diameter and rotatable. Probes are provided on both joining members (1) and (2). It is arranged at a position near the front side and the rear side in the moving direction of (12) in a manner orthogonal to the butting portion (3). The probe (12) is pressed by the probe (12) under the condition that the peripheral surface thereof is pressed against the surfaces of the two joining members (1) and (2) by the moving mechanism and the pressing mechanism. It moves while rolling the butting portion (3) in the moving direction.

The front and rear pressing rollers (20) (2)
By using 1), at the time of joining, both front and rear sides of the probe (12) of both joining members (1) and (2) are pressed,
As a result, the warpage and twist of the joining members (1) and (2) are corrected, and the joining members (1) and (2) can be made flat between the front and rear pressing rollers (20) and (21).
The contact area between the two joining members (1) and (2) can be increased. Further, the pressing rollers (20) (2)
1) presses both the front and rear sides of the probe (12) of both the joining members (1) and (2), and thus has an action of locally restraining both the joining members (1) and (2).

The front and rear pressing rollers (20)
In (21), the moving speed of the rear pressing roller (21) is equal to the moving speed of the probe (12), and the moving speed of the front pressing roller (20) is lower than the moving speed of the rear pressing roller (21). Can be controlled so that the speed is slightly higher. By controlling the moving speeds of the front and rear pressing rollers (20) and (21) to be different in this manner, the front and rear pressing rollers (20) and (21) are controlled.
The tension in the tensile direction can be applied to the abutting portion (3) between them.

That is, both front and rear pressing rollers (20) that move while rolling in the direction in which the probe (12) moves.
In (21), the peripheral surface thereof is pressed against the surfaces of the joining members (1) and (2), and the front pressing roller (20) moves more than the rear pressing roller (21). By controlling the speed to be high, the two joining members (1) and (2) are pulled forward from the contact portion of the front pressing roller (20).
This is because tension in the pulling direction occurs between the front and rear pressing rollers (20) and (21) in (2).

Next, a case where friction stir welding is performed using the welding device (10) and the front and rear pressing rollers (20) and (21) will be described.

The front and rear pressing rollers (20) and (21) are placed on the two joining members (1) and (2), and the two joining members (1) are mounted.
While pressing (2), the rotor (11) of the joining device is rotated to bring the probe (12), which rotates integrally with it, into contact with the butting portion (3) or its vicinity. The two joining members (1) and (2) are corrected for warp and twist by the front and rear pressing rollers (20) and (21), become flat between the front and rear pressing rollers (20) and (21), and become abutting portions ( 3) Adhesion state where no gap exists.

The contact portion between the two joining members (1) and (2) is softened and plasticized by frictional heat generated by the contact with the rotating probe (12), and the probe (12) is further pressed to push the probe (12). Is inserted into the thickness direction of the joining members (1) and (2). With the probe (12) inserted, the shoulder (11a) of the rotor (11) is brought into contact with the surfaces of the joining members (1) and (2). The contact of the shoulders (11a) can prevent the material of the softened portion from being scattered at the start of the joining or during the joining, so that a uniform joining state can be realized, and the joining members (1) (2) and the shoulder ( By generating frictional heat due to sliding with 11a), softening of the contact portion with probe (12) or the vicinity thereof is promoted, and furthermore, formation of unevenness on the surfaces of joining members (1) and (2) is prevented.

After the insertion of the probe (12), the probe (12) and the front and rear pressing rollers (20) and (21) are moved along the butting portion (3).

Then, the probe (12) and the rotor (1)
By the rotation of 1), the joining members (1) and (2) are softened and agitated by frictional heat around the contact portion with the probe (12). Then, by the movement of the probe (12), the softening and agitating portion receives the advancing pressure of the probe (12) and wraps backward in the traveling direction of the probe (12) so as to fill the passage groove of the probe (12). After that, it rapidly loses frictional heat and is quenched and solidified. At this time, the joining members (1) and (2) are subjected to joining distortion due to frictional heat, but the joining members (1) and (2) are distorted by the tension in the tensile direction applied to the butting portion (3) between the front and rear pressing rollers (20) and (21). The distortion is absorbed and the joint is made flat. Also, since both joining members (1) and (2) are flat by the front and rear pressing rollers (20) and (21),
The joints (3) are joined in a state where there is no gap.

In this manner, in a state where there is no gap in the butted portion (3) while being flat, rapid softening, stirring and cooling and solidification of the butted portion (3) are sequentially repeated with the movement of the probe (12). Then, the joining members (1) and (2) are integrated with each other at the butt portion (3) and sequentially joined to obtain a joined product in a good joined state.

In the above embodiment, the joining member (1)
Although (2) is integrated by butt joining, in the present invention, other than that, it may be integrated by lap joining.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Two thin and long joining members (1) and (2) each made of extruded A6N01-T5 aluminum and having a width of 200 mm, a length of 1000 mm and a thickness of 3 mm were used. End faces in the width direction were compared.

Then, using the joining device (10) and the pressing rollers (20) and (21) shown in FIG.
By rotating the rotor (11) and the probe (12) of
The probe (12) was inserted into the butt portion (3) until the rotor shoulder (11a) came into contact with the surfaces of the joining members (1) and (2), and friction stir welding was performed as follows.

Here, the outer diameter of the rotor (11) is 3 mm,
The outer diameter of the probe (12) is 9 mm, the insertion depth of the probe (12) is 3 mm, and the moving speed of the probe (12) is 60.
0 mm / min. The front and rear pressing rollers (2
0) and (21) are both 60 mm in outer diameter, and the distance between the probe (12) and the front pressing roller (20) is 90 mm.
mm, and the distance between the probe (12) and the pressing roller (21) on the rear side was set to 100 mm.

Embodiment 1 The moving speed of the rear pressing roller (21) was measured by the probe (1).
In addition to controlling the moving speed to be the same as 2), the moving speed of the front pressing roller (20) is also controlled by the probe (12).
The friction stir welding was performed while controlling the moving speed to be the same as the moving speed.

Embodiment 2 The moving speed of the rear pressing roller (21) is measured by the probe (1).
While controlling so as to be the same as the moving speed of 2), the moving speed of the front pressing roller (20) is controlled to be 10% faster than that of the rear pressing roller (21).
Friction stir welding was performed.

Comparative Example 1 Friction stir welding was performed without using the front and rear pressing rollers (20) and (21).

The joints obtained in Examples 1, 2 and Comparative Example 1 were inspected and measured for misalignment, joint efficiency, and maximum deflection. The results shown in Table 1 were obtained.

[0031]

[Table 1]

As shown in Table 1, in Examples 1 and 2,
There is no misalignment, the joint efficiency is improved as compared with the comparative example, and the maximum deflection amount is also small, indicating that a high-quality joined product can be obtained. Also, of these two embodiments, the front and rear pressing rollers (20) and (21)
In the second embodiment, in which the moving speed is varied and tension is applied to the butt portion (3) in the tensile direction, the joint efficiency is improved as compared with the first embodiment, and the maximum deflection amount is further reduced. I understand.

[0033]

As described above, according to the first aspect of the present invention, the abutting portion or the overlapping portion is formed on the two joining members before and after the moving direction of the probe in the moving direction of the probe. The joining member press roller that moves while rolling the part is arranged, and by these front and rear press rollers,
Friction stir welding is performed while holding both the front and rear sides of the probe of both joining members, so both joining members are flat between the front and rear holding rollers, increasing the contact area of both joining members and improving joint efficiency Can be done. Further, since the two joining members are joined in a flat state between the front and rear pressing rollers, occurrence of misalignment can be prevented. In addition, since both the joining members are joined in a restrained state in which the front and rear sides of the probe are pressed by the front and rear pressing rollers, distortion due to joining is suppressed, and deformation of the joining member can be reduced. . Therefore,
There is provided a joining method capable of preventing misalignment and obtaining a high-quality joined product having high joint efficiency and small deformation.

Further, the invention of claim 2 controls the moving speed of the front and rear pressing rollers so that the front pressing roller is relatively faster than the rear pressing roller. Since friction stir welding is performed while applying tension in the tensile direction to the abutting portion or the overlapping portion between the pressing rollers, the two joining members are further flattened by the tension in the tensile direction, and the contact area between the two joining members is reduced. The joint efficiency can be further improved. Further, the strain generated by the joining can be absorbed by the tension in the tensile direction, and the deformation of the joining member can be remarkably reduced. In addition, since the pressing roller before and after generating the tension moves on both joining members, the length of the joining member is not limited, and even if the joining roller is long, Bonding distortion can be absorbed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view of a state in which joining members used for friction stir welding in FIG. 1 are butted.

FIG. 3 is a perspective view for explaining a friction stir welding method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 2 ... Joining member 3 ... Butt part 4 ... Step 10 ... Joining device 11 ... Rotor 12 ... Probe 20, 21 ... Joining member pressing roller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ichiro Iwai 6,224 Kaiyamacho, Sakai City Showa Aluminum Co., Ltd. (72) Inventor Takenori Hashimoto 6,224 Kaiyamacho Sakai City, Showa Aluminum Co., Ltd.

Claims (2)

[Claims] 1. A rotating probe (12) is inserted into the butting portion (3) of two plate-shaped joining members (1) and (2) or a superposed portion or in the vicinity thereof to frictionally contact the probe. While softening and stirring with heat, the probe (12) is relatively moved along the butt portion (3) or the overlapping portion in the inserted state, so that the joining members (1) and (2) are butt-joined or In the friction stir welding method in which lap welding is performed, a butting portion (3) or an overlapping portion is formed on the both joining members (1) and (2) before and after the moving direction of the probe (12) in the direction in which the probe moves. The joining member pressing rollers (20) and (21) that move while rolling are arranged, and the joining members (1) are moved by the front and rear pressing rollers (20) and (21).
(2) A friction stir welding method in which friction stir welding is performed while holding both the front and rear probes (12). 2. The moving speed of the front and rear pressing rollers (20) and (21) is controlled such that the front pressing roller (20) is relatively faster than the rear pressing roller (21). The friction stir welding method according to claim 1, wherein the friction stir welding is performed while applying tension in a tensile direction to the abutting portion (3) or the overlapping portion between the front and rear pressing rollers (20) (21).