JP2000042762A - Friction stirring joining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction stirring joining method that causes no holes or recesses after a probe is pulled out, in joining members having parts to be welded in the peripheral direction on the circumferential surface. SOLUTION: The end faces are abutted on each other of the two joining members 1, 2 that consist of an aluminum pipe material having a circular cross section, with a rotating probe 22 inserted into this abutted part. Then, while the part in contact with the probe 22 is softened by frictional heat and stirred, the joining members 1, 2 are rotated so that the abutted part successively passes through the probe 22. When the joining members 1, 2 make one rotation, they are stopped. After that, an abutting member 10 is applied against the joining end W2 in the tangential direction of the seam in this joining end. Then, the probe 22 is moved to the abutting member 10.

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 a metal material such as an aluminum material (including an aluminum alloy material), and more particularly, to a joining method having a circular cross section or a polygonal cross section. The present invention relates to a friction stir welding method for joining peripheral surfaces of members in a circumferential direction.

[0002]

2. Description of the Related Art As shown in FIG. 8A, for example, a joining member (5) made of two metal pipes having a circular cross section is used.
1) When the end faces of (52) are butted together and these two joining members (51) and (52) are joined over the entire circumference of the butted portion (53), friction stirring which is one of the solid-phase joining methods is used. A joining method may be used.

The friction stir welding method will be described as follows. That is, as shown in the figure, a small-diameter pin-shaped probe (6) is placed on the end axis of the large-diameter cylindrical rotor (61).
2) Using a joining tool (60) provided integrally with the projecting portion, the rotor (61) is rotated and the abutting portion (53) of both joining members (51) and (52) is joined from the outer peripheral surface thereof. Insert the probe (62). Insertion is generally
A shoulder (61) consisting of a flat surface on the probe side of the rotor (61)
This is performed until a) comes into contact with both joining members (51) and (52).

[0004] Then, as shown in FIG. 8 (b), while the probe is in the inserted state, the butting portion (53) moves the probe (6).
The two joining members (51) and (52) are sequentially passed through 2).
Is rotated about its axis (Q). Or,
Although not shown, the probe (62) may be moved in the circumferential direction of the joining members (51) and (52) along the butting portion (53) in the inserted state. The probe (62) is generated by frictional heat generated by rotation of the probe (62) or frictional heat generated by sliding between the shoulder (61a) of the rotor (61) and the two joining members (51) and (52). ) Are softened and agitated by the probe (62) in the vicinity of the contact portion with the probe (62), and with the rotation of the two joining members (51), (52) or the probe (62). With the movement, the softening and stirring portion plastically flows so as to fill the passage groove of the probe (62), and then rapidly loses frictional heat and is cooled and solidified. This phenomenon is sequentially repeated with the rotation of the two joining members (51) and (52) or with the movement of the probe (62), and finally the two joining members (51) and (52) are brought into contact with each other. 53). In the same figure, (X) is a joining bead portion formed by the friction stir welding, which is formed along the butting portion (53). Also, (X
1) is a joining start end.

According to such a friction stir welding method, since it is a solid-phase welding, there are advantages such as being not limited to the kind of metal material as a joining member, and being less deformed due to thermal distortion during welding.

By the way, the joining members (51) (5)
In the case of friction stir welding of 2), the welding start end (X
When 1) returns to the insertion position of the probe (62), since there is no need to join any more, after the rotation of the joining members (51) and (52) is stopped, as shown in FIG.
2) must be withdrawn from the joining members (51), (52).

[0007]

However, when the probe (62) is pulled out from the outer peripheral surface of the joining members (51) and (52) in the axial direction, the diameter of the probe (62) must be always at the joining end portion (X2). The hole (54) corresponding to the insertion depth remains. Since the holes (54) locally reduce the bonding strength, they must be removed or filled after the bonding is completed.

As the hole processing means, a method of embedding a pin in the hole (54) and a method of filling the hole (54) with molten metal by fusion welding such as TIG and MIG have been proposed. However, in the method of embedding the pin, since the pin is merely fixed by mechanical biting, the reliability in strength is poor.
Further, the fusion welding method has problems such as a decrease in bonding strength and thermal distortion caused by welding heat generated during welding.

In addition, although not shown in the drawings, when a joining member such as a plate member having a straight joining portion on its surface is joined by friction stir welding, the joining end portion does not return to the starting end portion. Attach end tabs to the joint terminations at the end faces of the members in the direction of the joint, and probe (6).
After moving 2) to the end tab, it is effective to pull out the probe from the end tab and then remove the end tab.

However, when this method is applied to a circumferential joining performed along a peripheral surface of a joining member having a circular cross section or a polygonal cross section, such as the above-described circumferential joining, the end tab is attached to the joining member. This cannot be applied because the place does not exist.

In the case of joining the joining members (51) and (52), the inserted probe (62) may be pulled out from the other end surface of the joining members (51) and (52). The joining members (51) and (52)
Concave portion (not shown) on the other end face of probe
Is formed, which causes a problem that the appearance of the obtained joint product is deteriorated.

The present invention has been made in order to solve such a problem. In a friction stir welding method for joining a joining member having a joining portion in a circumferential direction on a peripheral surface, a hole or a concave portion after pulling out a probe is removed. It is an object of the present invention to provide a friction stir welding method that does not cause the friction stir welding.

[0013]

In order to achieve the above object, the present invention provides a joining member having a circumferential joining portion on a peripheral surface, wherein a rotating probe is inserted into the joining portion.
In a friction stir welding method of joining the joining members by relatively moving the probe along the joining portion in an inserted state while softening and stirring the contact portion with the frictional heat with the frictional heat, the joining member And applying a contact member in a direction tangential to or close to the joining line at the joint end portion, and moving the inserted probe through the joint end portion to the contact member. .

[0014] According to this, at the joining end portion of the joining member,
By applying the contact member in a direction tangential to or near the joining line at the joint end portion, the probe in the inserted state can be moved to the contact member in the inserted state. Then, when the probe enters the contact member, the softened portion of the contact member that contacts the probe plastically flows rearward, and fills the groove formed after the passage of the probe. Next, the probe in the inserted state moved to the contact member is pulled out from the contact member. By doing so, holes and recesses after the probe is pulled out are not left in the joint, so that a decrease in the joint strength of the joint can be prevented, and the strength reliability of the joint is improved. After that,
By removing the abutment member, holes and recesses after the probe is pulled out of the joining member no longer remain, and therefore, it is possible to prevent a decrease in the appearance of the joined product caused by the holes and the recessed portion after the probe is pulled out, and therefore, to reduce the appearance of the joined product. Will be able to maintain.

[0015]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIGS. 1 to 6 show an embodiment of the present invention. In FIG. 1, (1) and (2) are two joining members made of a rod-shaped aluminum extruded pipe having a circular cross-section and a predetermined length. These joining members (1)
(2) have the same shape and the same size. And these joining members (1) and (2) are arrange | positioned in the aspect which abuts end surfaces. In this abutting state, the axes (P) and (P) of these joining members (1) and (2) are coincident,
Therefore, the outer peripheral surface of one joining member (1) and the outer peripheral surface of the other joining member (2) are flush.

This embodiment is similar to the prior art described above.
The two joining members (1) and (2) arranged in a butted state are
This shows a case where friction stir welding is performed over the entire circumference of the butt portion (3). Therefore, the butting portion (3) becomes a joining portion of the joining members (1) and (2), and the joining members (1) and (2)
The circumferential direction at the butting portion (3) is the joining line direction.
And the joined product joined by this friction stir welding,
It is used as a member for a suspension arm, a member for an engine mount, a member for a space frame, and the like.

A joining tool (20) is provided with a small-diameter pin-shaped probe (22) protruding and provided integrally with the end axis of a large-diameter cylindrical rotor (21). The probe (2) is rotated by rotating the rotor (21) at a high speed.
2) also rotates at high speed. The probe (22) and the rotor (21) are connected to the joining member (1).
It is made of a heat-resistant material that is harder than (2) and can withstand frictional heat generated at the time of joining.

(10) is a plate-shaped aluminum contact member. This contact member (10), as described later,
Probe (22) at the joint end of joining members (1) and (2)
And is applied to the joining end portion in the tangential direction of the joining line at the joining end portion, and one surface in the thickness direction is defined as a probe passage surface (11), One end surface in the length direction is used as a contact surface (12) with the joining member. The probe passage surface (1
1) is a flat surface, while the contact surface (12) is a curved surface curved in an arc shape corresponding to the outer peripheral surface of the joining members (1) and (2). And this contact member (10)
When this is applied to the joining end portion (W2) in the tangential direction of the joining line at the joining end portion (see FIG. 4A), the contact surface (12) has the joining member (1) ( The outer peripheral surface of (2) is brought into contact with the outer peripheral surface in a surface contact state, and the probe passage surface (11) is flush with the outer peripheral surfaces of the joining members (1) and (2) at the joining end portion (W2). .

The contact member (10) is stably supported by the block-shaped metal support member (13). The support member (13) is
At the same time, the contact member (1) is applied to the outer peripheral surface of the joining member (2), and the contact surface (14) of the joining member (1)
The curved surface is curved in an arc shape so as to correspond to the outer peripheral surface of (2). Then, when the support member (13) abuts the contact member (10) on the joint end portion (W2),
The contact surface (14) contacts the outer peripheral surfaces of the joining members (1) and (2) in a surface contact state. The friction stir welding according to the present invention is performed as follows. That is, the probe (22) in the rotating state of the welding tool (20) is moved to the position shown in FIG.
And, as shown in FIG. 2A, it is inserted into the butting portion (3) from its surface. Then, as shown in FIG. 2B, in the probe inserted state, the flat shoulder (21a) at the tip of the rotor (21) is brought into contact with the outer peripheral surfaces of the joining members (1) and (2). However, it is possible to prevent the material from being scattered in the softened portion at the start of the welding or during the welding, to realize a uniform joining state, and to cause frictional heat by sliding between the joining members (1) and (2) and the shoulder (21a). To promote softening of the contact portion with the probe or in the vicinity thereof, and furthermore, the joining member (1)
It is preferable from the viewpoint of preventing the formation of unevenness on the outer peripheral surface of (2).

Then, with the probe inserted, the joining members (1) and (2) are rotated about their axis (P) as a rotation axis so that the butting portion (3) sequentially passes through the probe (22).

The frictional heat generated by the rotation of the probe (22), or the frictional heat generated by the sliding between the shoulder (21a) of the rotor (21) and the outer peripheral surfaces of the joining members (1) and (2). As a result, the joining members (1) and (2) are softened and agitated in the vicinity of the contact portion with the probe (22), and the softened and agitated portion is moved by the rotation of the joining members (1) and (2). After the plastic flow to fill the passage groove of (1), the frictional heat is rapidly lost and the solidified material is cooled and solidified. This phenomenon is sequentially repeated with the rotation of the joining members (1) and (2). As shown in FIG. 3A, the joining members (1) and (2) are integrated at the butting portion (3). And are joined sequentially. In FIG. 3A, (W)
Is a joining bead portion formed by the friction stir welding, and is formed along the butt portion (3). Also,
(W1) is a joining start end.

When the joining start end (W1) returns to the insertion position of the probe (22), or when the joining start end (W1) further passes through the insertion position of the probe (22), that is, when the joining member ( 1) (2) is more than one rotation,
When rotated, as shown in FIG. 3 (b), the two joining members (1) and (2) are joined over the entire circumference of the butted portion (3), and the joining is completed. When the probe (22) is pulled out from the outer peripheral surfaces of the joining members (1) and (2) at the probe insertion position, as described in the related art,
A withdrawal hole of the probe is generated at the joint end portion (W2).

Then, after the rotation of the joining members (1) and (2) is stopped, the contact member (10) supported by the supporting member (13) is moved to the joining end portion (FIG. 4A). W
2) is applied in the tangential direction of the joining line at the joining end portion (W2). In the state where the contact member (10) is thus applied to the joint end portion (W2), the contact member (10)
The probe passing surface (11) is flush with the outer peripheral surfaces of the joining members (1) and (2) at the joining end portion (W2). Although not shown, the contact member (10) may be applied in advance before the joining members (1) and (2) make one rotation.

Next, as shown in FIG. 4B, the inserted probe (22) is moved to the contact member (10). When the probe is moved, the probe passage surface (11) of the contact member (10) is flush with the outer peripheral surfaces of the joining members (1) and (2) at the joining end portion (W2). ) Can be smoothly moved to the contact member (10) in the inserted state.

When the probe (22) enters the contact member (10) in this manner, the contact softening portion of the contact member (10) with the probe (22) plastically flows backward, and the probe (22) The grooves formed after the passage are filled, so that no holes or recesses remain at the joining end portions (W2) of the joining members (1) and (2).

Next, the probe (22) moved to the contact member (10) is moved to the contact member (10) as shown in FIG.
From the probe passage surface (11). Then, a withdrawal hole (4) for the probe is formed in the contact member (10). As shown in FIG.
0) is cut and removed along the outer peripheral surfaces of the joining members (1) and (2). By doing so, holes and recesses do not remain at the probe passage marks on the joining members (1) and (2), so that a joined product having a good joining state can be obtained.

Although not shown, the contact member (1
The probe (22) moved to the position (0) may be pulled out from the end face of the contact member (10), and then the contact member (10) may be removed.

Further, the step of joining the butting portions (3) of the joining members (1) and (2) and the step of moving the probe (22) to the contact member (10) may be separately performed. That is, for example, after joining the butting portions (3) of the joining members (1) and (2), the probe (22) is pulled out from the joining members (1) and (2), whereby the probe is pulled out to the joining end portion (W2). A plurality of joined articles having the hole (4) formed therein are manufactured in advance, and then the contact member (10) is applied to the joint end portion (W2) of the joined article, and the probe is drawn into the probe extraction hole (4). The probe may be inserted again to move the probe to the contact member (10).

As described above, the contact member (10)
Part of the material is filled in the probe passage at the end of the joint of the joining members (1) and (2) to form a part of the joining member. Therefore, the contact member (10) is used as the joining member (1). It is desirable to be made of the same material as (2).

FIG. 7 shows a modification of the above embodiment.

This modification shows a case where butt joining of a plurality of joining members is continuously performed. The friction stir welding method will be described below.

That is, as shown in FIG. 2 (i), the probe (22) of the welding tool (20) is inserted into the butting portion (3) of the welding members (1) and (2) as in the above embodiment. I do. Then, when the joining members (1) and (2) rotate one or more turns, and the joining members (1) and (2) are joined over the entire circumference of the butt portion (3), the joining members (1) and (2) After the rotation of 2) is stopped, one end of the abutment member (10) is applied to the joint end portion (W2), and the other end of the abutment member (10) is joined to the abutting portion (3) of the unjoined joint members (1 ') and (2'). '). Next, as shown in FIG.
2) is moved to the contact member (10). The probe (22) is further moved to join the probe (22) to the unjoined joining member (1 ') as shown in FIG.
(2 ') into the butting portion (3'). Next, the joining member (1 ′) in an unjoined state with the contact member (10)
After cutting (cutting portion 10a) along the outer peripheral surface of (2 '), the butted portion (3') of the joining member (1 ') (2') in the unjoined state is shown in FIG. Thus, friction stir welding is performed in the same manner as in the above embodiment.

This makes it possible to continuously perform the butt joining of a plurality of joining members, so that no holes or recesses remain after the probe is pulled out, that is, a good joining state is obtained. Goods can be obtained efficiently.

Further, the present invention is not limited to the above embodiment.

For example, instead of rotating the joining members (1) and (2), the joining members (1) and (2) are fixed,
The probe (22) may be moved along the butting portion (3) of the joining members (1) and (2).

Further, the contact member (10) is connected to the joint end portion (W
The direction corresponding to 2) may be a direction close to the tangential direction of the joining line at the joining end portion (W2).

Of course, the joining members (1) and (2) may be made of a metal material other than aluminum,
It does not need to be a pipe material, and may be a solid material.

[0039]

As described above, according to the present invention, a rotating probe is inserted into the joining portion of the joining member having the joining portion in the circumferential direction on the peripheral surface, and the contact portion with the probe is softened by frictional heat. In the friction stir welding method of joining the joining members by relatively moving the probe along the joining portion in the inserted state while stirring and stirring, the joining terminus of the joining member is Since the contact member is applied in the tangential direction of the joining line or in a direction close to the joining line, and the probe in the inserted state is moved through the joining end portion to the applying member, friction stirring according to the present invention is performed. According to the joining method, the groove formed after the passage of the probe can be filled by the softened portion of the contact member that comes into contact with the probe. Therefore, even when the joining member having the joining portion in the circumferential direction on the peripheral surface is joined by friction stir welding, no hole or recess remains after the probe is pulled out at the joining end portion, that is, the joining strength of the joining portion is high. In addition, a joined product having high strength reliability can be obtained. Furthermore, by removing the probe after pulling out the probe from the contact member, it is possible to obtain a joined product in which no holes or concave portions remain after the probe is pulled out of the joint member, that is, the appearance is good.

[Brief description of the drawings]

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

FIGS. 2A and 2B show the same embodiment, and FIG. 2A shows II- in FIG.
FIG. 2B is a cross-sectional view taken along the line II, and FIG.

FIGS. 3A and 3B are views showing the same embodiment, in which FIG. 3A is a cross-sectional view showing a state in which the joining member is rotating, and FIG.

FIGS. 4A and 4B are diagrams showing the same embodiment, in which FIG. 4A is a cross-sectional view in which a contact member is applied to a joining end portion, and FIG. 4B is a cross-sectional view in a state in which a probe is moved to the contact member.

5A and 5B are diagrams showing the same embodiment, wherein FIG. 5A is a perspective view showing a state where a probe is moved to a contact member, and FIG. 5B is a perspective view showing a state where the probe is pulled out from the contact member.

FIG. 6 is a view showing the same embodiment, and is a perspective view of a state in which a contact member is separated from a joining member.

FIGS. 7A and 7B are views showing a modification of the embodiment, in which FIG. 7I is a cross-sectional view showing a state where the joining member is rotating, FIG. 7B is a cross-sectional view showing a state where the probe is moved to the contact member, and FIG. () Is a cross-sectional view of a state where the contact member is separated from the unjoined joining member.

FIGS. 8A and 8B are views showing a conventional friction stir welding, in which FIG. 8A is a perspective view of a joining member before joining, and FIG.

FIG. 9 is a view showing a defect of the conventional friction stir welding, and is a perspective view of a state after the joining members are joined.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 2 ... Joining member 3 ... Butt part (joining part) 4 ... Probe extraction hole 10 ... Contact member 13 ... Support member 20 ... Joining tool 22 ... Probe W ... Joining bead part W1 ... Joining start end part W2 ... Joining end part

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takenori Hashimoto 6,224, Kaiyamacho, Sakai City Showa Aluminum Co., Ltd. F term (reference) 4E067 AA05 BG02 CA01 DA17 EC06

Claims (1)

[Claims] 1. A rotating probe (22) is inserted into a joint (3) of a joining member (1) (2) having a joint (3) in a circumferential direction on a peripheral surface, and a contact portion with the probe is provided. The probe (22) is relatively moved along the joint (3) in the inserted state while softening and stirring with frictional heat, thereby frictionally stirring the joining members (1) and (2). In the joining method, the contact member (10) is applied to the joining end portion (W2) of the joining member in a direction tangential to or close to the joining line at the joining end portion, and the probe (22) in the inserted state is A friction stir welding method characterized by passing through a welding end portion (W2) and moving to a contact member (10).