JP2001321965A - Corner joining method by friction stir welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corner joining method by friction stir welding capable of preventing generation of a joining defect at a joining part in the corner joining method by friction stir joining to join butt ends of two joining members assembled to form a corner part. SOLUTION: A joining auxiliary material 7 of a triangular shaped cross section is filled/arranged to a corner part 5. A probe 12 of a joining tool 10, while rotating, is inserted into the butting faces 3 of both joining members 1, 2 through the joining auxiliary material 7. Further, an end face 11a of a rotating piece 11 of the joining tool 10 is brought into pressure contact with an outer face 7a of the joining auxiliary material 7. At this state, by relatively moving the probe 12 along the butting part 3, both joining members 1, 2 are corner-joined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corner joining method by friction stir welding in which joints of joints having corners (for example, T joints and lap joints) are joined from the corners.

[0002]

2. Description of the Related Art The following methods have been proposed as friction stir welding methods that fall into the category of solid-state welding methods. That is, FIG.
As shown in the figure, the end face (111) of the large-diameter cylindrical rotor (111)
a) using a welding tool (110) in which a small-diameter pin-shaped probe (112) is integrally protruded on the axis of rotation of the rotor (11);
By rotating 1), the probe (112) is rotated, and the probe (112) is placed in a butt state.
Butt joint (103) of two flat joining members (101) (102)
Insert The insertion is performed until the end face (111a) of the rotor (111) comes into contact with the surfaces of the joining members (101) and (102). Then, in this state, the probe (112) is moved relative to the two joining members (101) and (102) along the butting portion (103).

[0003] Then, the frictional heat generated by the rotation of the probe (112) and the frictional heat generated by the sliding between the end face (111a) of the rotor (111) and the surfaces of the joining members (101) and (102). As a result, the two joining members (101) and (102) are softened in the vicinity of the contact portion with the probe (112), and the softened portions are stirred and mixed by receiving the rotational force of the probe (112), and are mixed. ), The stirring portion plastically flows so as to fill the passage groove of the probe (112), and then loses frictional heat and is cooled and solidified. This phenomenon is repeated sequentially with the movement of the probe (112),
Finally, both joining members (101) and (102) are butted part (103)
Are joined together (joined portion W ′).

[0004] This friction stir welding method falls into the category of the solid-state welding method, and has excellent advantages such as being not restricted by the type of metal material to be joined and having a small thermal distortion due to joining.
In recent years, it has been used at an assembly site of various structures.

[0005]

By the way, in structures such as panels for ships and vehicle floors, such as LNG tanks,
As shown in FIG. 10, a joining portion (12) of two plate-like joining members (121) and (122) joined so as to have a T-shaped cross section.
3) may need to be joined from the corners (125) and (126). In this case, there were the following difficulties.

That is, as shown in FIG. 11, the joining tool (1) is attached to a joint (123) of both joining members (121) and (122).
Place the probe (112) on the surface (12) on both sides of the corner (125).
1a) When inserted from between (122a), the end face (111a) of the rotor (111) becomes the surface (121a) (122a) on both sides of the corner (125).
In any of the above, there is a problem that frictional heat cannot be sufficiently generated since a contact state cannot be brought into contact with any of the above, and a joining defect easily occurs.

Further, as shown in FIG. 10, when there is unevenness such as a cutting mark on the mating surface of one joining member (122), the unevenness is formed on the surface of the other joining member (121). When combined, a gap (124) due to the unevenness is formed in the joint (123). When friction stir welding is performed on the mating portion (123) from the corner portion (125) in such a state, there is a problem in that an unjoined portion or a void is generated in the joined portion and a joining defect is easily generated. .

The present invention has been made to solve such a problem, and an object of the present invention is to join a joining portion of two joining members joined so that a corner is formed from the corner. A corner joining method by friction stir welding,
An object of the present invention is to provide a corner joining method by friction stir welding that can prevent a joining defect from occurring at a joining portion.

[0009]

In order to achieve the above object, the invention according to claim 1 uses a joining tool in which a small-diameter probe is protruded on a rotation axis of an end face of a large-diameter rotor. The rotating probe is inserted from the corner into or near the joining portion of the two joining members joined so that the portion is formed, and in this state, the probe is relatively moved along the joining portion. This is a corner joining method by friction stir welding for corner joining both joining members, in which a joining auxiliary material having a triangular cross section is filled and arranged in the corner, and a probe is joined at the corner through the joining auxiliary material or It is characterized in that the two joining members are completely joined by inserting the rotor into the vicinity thereof, bringing the end face of the rotor into contact with the outer surface of the joining auxiliary material, and softening and agitating the joining auxiliary material together with the two joining members. .

According to the first aspect of the present invention, the joining auxiliary material having a triangular cross section is filled and arranged in the corner, so that the end face of the rotor of the welding tool can be brought into contact with the outer surface of the welding auxiliary material at the time of welding. become. As a result, a sufficient amount of frictional heat can be generated, thereby preventing the occurrence of joining defects due to insufficient frictional heat.

Further, in this corner joining method, at the time of joining, a part of the base material of the softened portion of the joining auxiliary material softened by the frictional heat receives the pressure from the end face of the rotor and enters into the gap formed in the joining portion. In this state, the softened portions of the two joining members and the softened portion of the joining auxiliary material are stirred and mixed by receiving the rotational force of the probe, and the stirred portions lose frictional heat and are cooled and solidified. Therefore, even when a gap is formed in the joining portion, it is possible to prevent the occurrence of a joining defect such as an unjoined portion or a void.

According to a second aspect of the present invention, in the corner joining method by friction stir welding according to the first aspect, the corner portion is
It is formed on both sides of one of the joining members of both joining members, and the joining in each corner is simultaneously performed by using a joining tool for each corner.

According to the second aspect of the present invention, by simultaneously performing the joining at the corners, the time required for the joining is reduced, and the efficiency of the joining operation is improved.

According to a third aspect of the present invention, in the corner joining method by friction stir welding according to the first or second aspect, the joining auxiliary material is provided integrally with one of the two joining members. Adopted that.

According to the third aspect of the invention, by joining the two joining members, the joining auxiliary material is filled and arranged in the corner. As a result, it is not necessary to separately perform the filling operation of the joining auxiliary material, and the joining operation efficiency is remarkably improved.

[0016]

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

FIG. 1 to FIG. 4 show a first embodiment of the present invention.

In FIG. 1, (1) is a plate-like first joining member, and (2) is a plate-like second joining member. These joining members (1) and (2) are made of extruded aluminum or aluminum alloy (for example, A6061 and A5083). Then, one end face (matching surface) in the width direction of the second joining member (2) is fitted to the surface of the first joining member (1). Therefore, as shown in FIG. 4, the second joining member ( One corner portion (5) (6) is formed on each side of the thickness direction 2). Each corner (5)
In (6), as will be described later, a joining auxiliary material (7) (8)
Are arranged.

Further, fine irregularities (not shown) are formed on the mating surface of the second joining member (2), and therefore, the joining portion (3) of the two joining members (1) and (2) is formed. In addition, a gap (not shown) due to the fine unevenness is formed. On the other hand, at the other end in the width direction of the second joining member (2),
The flange portion (2c) has a T-shaped cross section and is integrally formed.

As shown in FIG. 4, at the two corners (5) and (6), one of the two surfaces (2a) and (2b) in the thickness direction of the second joining member (2) (FIG. 4). 4, the corner angle (θ1) of the first corner (5) formed between the surface (2a) of the first joining member (1) and the surface (2a) of the first joining member (1).
Is a right angle, and a second corner formed between the surface (2b) of the other (left side in FIG. 4) of the second bonding member (2) and the surface (1b) of the first bonding member (1). The corner angle (θ2) of the portion (6) is also a right angle.

In the first corner portion (5), a first joining auxiliary member (7) having a triangular cross section is provided with the first corner portion (5).
A second joining auxiliary material (8) having a triangular cross section is also filled and arranged along the second corner (6) in the second corner (6). . The first joining auxiliary material (7) and the second joining auxiliary material (8) have the same shape and the same size, and are made of the same material as the two joining members (1) and (2).

The first joining auxiliary material (7) has a top angle having an angle α1 equal to the corner angle (θ1) of the first corner portion (5) and two bottoms having angles β1 and γ1 smaller than 90 °. The first joining auxiliary material (7) is filled in the first corner portion (5), and the outer surface (7a) serving as the bottom surface of the first joining auxiliary material (7) is filled in the first corner portion (5). The first corner portion (5) forms an inclined surface with respect to the surfaces (1a) and (2a) on both sides. Similarly, the second joining auxiliary material (8) includes a vertex angle having an angle α2 equal to the corner angle (θ2) of the second corner portion (6), and an angle β2 smaller than 90 °.
It has a triangular cross-section with two base angles having γ2, so that the second joining auxiliary material (8) is filled in the second corner (6), The outer surface (8a) forms an inclined surface with respect to the surfaces (1b) and (2b) on both sides of the second corner portion (6). Furthermore, the width dimension of the outer surface (7a) (7b) of each joining auxiliary material (7) (8) is determined by the cylindrical rotors (11) (2) of the welding tools (10) (20) described later.
The diameter is set to be the same or slightly larger than the diameter of the end faces (11a) and (21a) of 1).

In the first embodiment, both the first and second joining auxiliary members (7) and (8) have vertical angles α1, α2 of right angles and two base angles β1, γ1, β2. , Γ2 is 45 °
And formed integrally with the corresponding surfaces (2a) and (2b) of the second joining member (2) during the extrusion process of the second joining member (2). The first and second joining assistants (7) and (8) are provided with the first joining member (2) in a state where the mating surface of the second joining member (2) is matched with the surface of the first joining member (1). The surface of the joining member (1) is exactly abutted, whereby the rising posture of the second joining member (2) is stably held, and the tilting of the second joining member (2) during the joining operation is prevented. I have.

In FIG. 4, (10) is a first friction stir welding tool for joining the joining portion (3) of both joining members (1) and (2) from the first corner (5). Similarly,
(20) is a second friction stir welding tool for joining the joining part (3) from the second corner part (6). These first and second welding tools (10) and (20) have the same configuration. When this configuration is described mainly with respect to the first welding tool (10), the first welding tool (10) has a large diameter circle. It includes a columnar rotor (11) and a small-diameter pin-shaped probe (12) protruding from a rotation line on an end face (11a) of the rotor (11). The rotor (11) and the probe (12) are both joined members (1)
It is made of a heat-resistant material that is harder than (2) and can withstand frictional heat generated during joining. Further, a projection (not shown) for agitating the softening portion is provided on the outer peripheral surface of the probe (12). The end face (11) of the rotor (11)
a) consists of a flat surface. Further, a corner (11c) between the outer peripheral surface (11b) and the end surface (11a) of the rotor (11) is chamfered with a radius r, whereby the corner (11
c) is rounded. By doing so, even if this corner (11c) comes into contact with one of the surfaces (1a) and (2a) on both sides of the corner (5) at the time of joining, the surface of Damage can be prevented.

Next, a procedure for joining the two joining members (1) and (2) will be described.

First, the probe (12) is rotated by rotating the rotors (11) and (21) of the two joining tools (10) and (20).
Rotate (22). Then, as shown in FIGS. 2 and 4, the probe (12) of the first joining tool (10) arranged between the surfaces (1a) and (22) on both sides of the first corner portion (5) is joined to both joints. It is inserted into the mating portion (3) of the members (1) and (2) from the outer surface side of the first joining auxiliary material (7) via the first joining auxiliary material (7), and the end face ( 11a) is pressed against the outer surface (7a) of the first joining auxiliary material (7). Similarly, the second
The probe (22) of the second welding tool (20) arranged between the corners (6) on both sides of the surface (1b) (2b)
And inserted from the outer surface side of the second joining auxiliary material (8) through the second joining auxiliary material (8) and the end face (21a) of the rotor (21) to the outer surface of the second joining auxiliary material (8). (8a). In the present invention, the probes (12) and (22) may be inserted into the mating portion (3) from the longitudinal end surfaces of the two joining members (1) and (2). Thus, in the first embodiment, the probe (12) of the first joining tool (10) is inserted so as to penetrate the first joining auxiliary material (7). The probe (22) is inserted while penetrating the second joining auxiliary material (8). Further FIG.
As shown in (2), the joining portion (3) of the two joining members (1) and (2)
The insertion positions of both probes with respect to the joining line (P) direction are the same. Then, in this state, both probes (12) and (22) are moved along the matching portion (3) at the same speed.

Then, the frictional heat generated by the rotation of the probe (12) of the first welding tool (10), the end surface (11a) of the rotor (11) and the outer surface (7a) of the first welding auxiliary material (7). Probe (12) due to frictional heat generated by sliding with the probe (12)
The two joining members (1) and (2) are softened in the vicinity of the contact portion with the first member, and the first joining auxiliary material (7) is also softened. Then, a part of the softened portion of the first joining auxiliary material (7) receives a pressing force from the end face (11a) of the rotor (11) and enters a gap formed in the joining portion (3). While being filled
The softened portions of the two joining members (1) and (2) and the softened portion of the first joining auxiliary material (7) are stirred and mixed by receiving the rotational force of the probe (22). Then, with the movement of the probe (12), the agitating portion receives the advancing pressure of the probe (12) and plastically flows so as to fill the passage groove of the probe (12).
It rapidly loses frictional heat and is cooled and solidified. On the other hand, the same phenomenon occurs in the movement of the probe (22) of the second welding tool (20) for the second welding auxiliary material (8) and the joint (3) of the two welding members (1) and (2). Accompany it. This phenomenon is caused by the probe (12) of both welding tools (10) and (20).
It is sequentially repeated with the movement of (22), and finally both joining members (1) and (2) are joined and integrated at the joining portion (3). In FIG. 1, (W) indicates a joint.

According to the corner joining method, the joining surfaces of the end faces (11a) and (21a) of the rotors (11) and (21) of the joining tools (10) and (20) are joined at the time of joining. Outer surface of (8) (7a)
(8a) can be brought into contact, so the mating part (3)
In this case, it is possible to sufficiently generate frictional heat, and it is possible to prevent the occurrence of joining defects due to insufficient frictional heat. further,
Since the joining is performed while a part of the softened portion of the base material of the joining auxiliary materials (7) and (8) is filled in the gap formed in the joining portion (8), occurrence of joining defects such as unjoined portions and voids is generated. Can be prevented. Therefore, in the joined product obtained as described above, a joining defect due to lack of frictional heat does not occur in the joining portion (W), and a joining defect such as an unjoined portion or a void due to a gap also occurs. There is no high-grade source.

Further, in this corner joining method, the outer peripheral surface (11) of the rotor (11) (21) is used as each joining tool (10) (20).
b) Corner (11c) (21) between (21b) and end face (11a) (21a)
Since the rounded chamfered c) is used, if these corners (11c) and (21c) are formed during the joining operation, the corners (5) and (6) will have the surfaces (1a, 2a) (1b, Even if it comes into contact with either one of the surfaces of 2b), the surface is not damaged due to the contact, so that it is possible to obtain a joined product with good surface condition on both corners (5) and (6). it can.

In addition, in this corner joining method, the joining at each corner (5) (6) is performed by using a joining tool (10) (20) for each corner (5) (6). Since they are performed simultaneously, the joining operation can be performed efficiently. In addition, both the first joining auxiliary material (7) and the second joining auxiliary material (8) are formed integrally with the second joining member (2), and the second joining member (2) is connected to the first joining member (1). ), Each joining auxiliary material (7)
Since (8) can be filled and arranged in the corners (5) and (6), there is no need to separately perform a filling operation for each of the joining auxiliary materials (7) and (8), and therefore, the joining work efficiency is remarkably improved. are doing.

FIGS. 5 to 7 show a second embodiment of the present invention. In these drawings, the same or similar elements as those in the first embodiment are denoted by the same reference numerals, and the second embodiment will be described below focusing on differences from the first embodiment.

In the second embodiment, as shown in FIGS. 5 and 6, both the first joining auxiliary material (7) and the second joining auxiliary material (8) are separate from the second joining member (2). It has become. Further, as shown in FIG. 5, undulating irregularities are formed on one end surface (matching surface) in the width direction of the second joining member (2), and therefore, both joining members (1) (2) are formed. 6), a gap (4) is formed due to the unevenness as shown in FIG. In FIGS. 5 and 6, the irregularities and the gap (4) are exaggerated for convenience of explanation.

Next, the procedure for joining the two joining members (1) and (2) will be described. In the second embodiment, first, a first joining auxiliary material (7) is filled and arranged along the first corner (5) in the first corner (5) of both joining members (1) and (2). At the same time, the second joining auxiliary material (8) is filled and arranged in the second corner portion (6) along the second corner portion (6). Next, the positions of the joining auxiliary members (7) and (8) are fixed, and as shown in FIG. 7, the first joining tool (10) and the second joining tool (20).
And each corner (5) in the same procedure as in the first embodiment.
The bonding in (6) is performed simultaneously. By doing so, a high-quality bonded product can be obtained with high work efficiency, as in the case of the first embodiment.

FIG. 8 shows a modification of the second embodiment. In this modified example, as shown in FIG. 2A, both end faces of the two flat joining members (1) and (2) are inclined with respect to the surfaces (1a) and (2a). . Then, by combining these end surfaces, a corner portion (5) is formed between the surfaces (1a) and (2a) of the two joining members (1) and (2). The corner angle of the corner portion (5) is a right angle as in the second embodiment.

In this modification, as shown in FIG. 2B, a joining auxiliary material (7) having a triangular cross section is provided in the corner (5).
And a receiving member having an L-shaped cross section (9)
Is attached to the outer corners of both joining members (1) and (2). Next, the joining portion (3) is joined from the corner portion (5) by the same joining operation as in the second embodiment using a joining tool (10). By doing so, a high-quality bonded product can be obtained as in the case of the second embodiment.

Although the embodiment of the present invention has been described above, the present invention is not limited to the first and second embodiments, and various settings can be changed.

For example, each of the first and second embodiments shows a case where the two joining members are completely joined by moving the probe of the joining tool along the joint of the two joining members. In this invention, the position of the probe of the joining tool may be fixed, and both joining members may be moved so that the two joining members are completely joined.

Of course, the corner joining method according to the present invention may be applied when joining the mating portion of the lap joint from the corner.

[0039]

As described above, in the corner joining method by friction stir welding according to the present invention, a joining auxiliary material having a triangular cross section is filled and arranged in the corner, and a probe is joined at the corner with the joining auxiliary material interposed therebetween. In addition, the end face of the rotor is brought into contact with the outer surface of the joining auxiliary material, and this joining auxiliary material is softened and stirred together with both joining members, so that both joining members are fully joined, so that frictional heat during joining is reduced. Sufficiently, it is possible to prevent the occurrence of joining defects due to insufficient frictional heat. In addition, even when a gap is formed in the mating portion, a part of the base material of the softened portion of the joining auxiliary material softened by the frictional heat is filled in the gap at the time of joining, so that the gap due to the gap is not formed. The occurrence of joint defects such as joints and voids can be prevented.

Further, the corners are formed on both sides of one of the joining members, and by using a joining tool for each of the corners, the joining at the corners can be performed simultaneously. In this case, the time required for joining can be reduced, and the efficiency of joining work can be improved.

Further, when the joining auxiliary material is provided integrally with one of the two joining members, it is not necessary to separately perform the filling operation of the joining auxiliary material, so that the efficiency of the joining operation is reduced. It can be further improved.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of the present invention, and is a perspective view of a state in the middle of joining.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a side view of both joining members of the first embodiment.

FIG. 5 is a view showing a second embodiment of the present invention, and is a perspective view of a state in which a joining auxiliary material is being filled and arranged.

FIG. 6 is a sectional view taken along line VI-VI in FIG.

FIG. 7 is a cross-sectional view corresponding to FIG. 2, showing a state in the middle of joining in the second embodiment.

FIGS. 8A and 8B are views showing a modification of the second embodiment, in which FIG. 8A is a cross-sectional view of a state in which a joining auxiliary material is being filled and arranged, and FIG.

FIG. 9 is a perspective view for explaining a conventional friction stir welding method.

FIG. 10 is a perspective view in a case where a gap is formed in a joining portion of both joining members.

FIG. 11 is a cross-sectional view showing a drawback of the conventional corner welding method using friction stir welding.

[Explanation of symbols]

 1, 2 ... joining member 3 ... joining part 4 ... gap 5 ... first corner part 6 ... second corner part 7 ... first joining auxiliary material 8 ... second joining auxiliary material 10, 20 ... joining tool 11, 21 ... rotation Element 11a, 21a: End face of rotor 11b, 21b: Outer peripheral face of rotor 11c, 21c: Corner 12, 22, Probe W: Joint

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masatoshi Enomoto 224 Kaiyamacho, Sakai City Showa Aluminum Co., Ltd. F-term (reference) 4E067 BG00 DA13 EC00 EC03

Claims (3)

[Claims] 1. A corner portion (5) is formed by using a welding tool (10) having a small-diameter probe (12) projecting on the rotation axis of an end face (11a) of a large-diameter rotor (11). The rotating probe (12) is inserted from the corner (5) into or near the mating portion (3) of the two joining members (1) and (2) that have been mated, and in this state, By moving the probe (12) relatively along the joining part (3), the two joining members (1)
This is a corner joining method based on friction stir welding for corner joining of (2), in which a joining auxiliary material (7) having a triangular cross section is filled and arranged in a corner (5), and a probe (12) is provided in the corner (5). Is inserted into or near the mating portion (3) via the joining auxiliary material (7), and the end face (11a) of the rotor (11) is brought into contact with the outer surface (7a) of the joining auxiliary material (7), This joining auxiliary material (7)
By softening and stirring together with the two joining members (1) and (2), thereby corner joining the two joining members. 2. The corner portion includes two joining members (1) and (2).
The friction stir welding according to claim 1, wherein the welding is performed on both sides of one of the joining members (2), and the joining in each corner is performed simultaneously by using a joining tool for each corner. Corner bonding method. 3. The corner joining method by friction stir welding according to claim 1, wherein the joining auxiliary material (7) is provided integrally with one of the joining members (2).