JP2023107059A - Friction stir joining method and friction stir joining device - Google Patents

Abstract

To provide a friction stir joining method and a friction stir joining device that suppress deformation of a hollow material, and can obtain a friction stir joining part, in friction stir joining of overlapping a plate material composed of a metal material, and the hollow material which is composed of the same kind as or different kind of a material from the plate material and has a closed cross section having an outer surface where the plate material is overlapped and an inner surface that is a surface opposite to the outer surface.SOLUTION: A friction stir joining method includes: an overlapping step of overlapping a plate material 30, and a hollow material 20; and a friction stir joining step of forming a friction stir joining part 31 between the plate material 30 and the hollow material 20 using a rotated joining tool 40. The friction stir joining step provides a deformation suppression mechanism 50 for suppressing deformation of the hollow material 20 in at least a partial region corresponding to a region where the friction stir joining part 31 is formed out of an inner surface 23.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a friction stir welding method and a friction stir welding apparatus, and more particularly to a friction stir welding method and a friction stir welding apparatus for friction stir welding a plate material and a hollow material.

Vehicle equipment such as automobiles is required to be lighter in order to improve fuel efficiency, reduce _CO2 emissions, and improve steering performance. and other members are required. Friction Stir Welding (FSW) is known as a method for joining metals or metals and nonmetals such as resins using such hollow materials. In this joining method, a stirring pin made of a high-strength material such as steel is rotated and pushed into the joining part of a soft material such as aluminum, thereby partially plastically flowing and joining the base materials to be joined. is. Since the friction stir welding method is suitable for soft base materials, it has been widely used industrially for joining aluminum materials. can also be used. Recently, not only metals of the same kind but also metals of the same kind, for example, a friction stir welding method between dissimilar metals such as aluminum and iron shown in Patent Document 1, or a metal and a metal such as resin shown in Patent Document 2 The friction stir welding method between metals and non-metals is also attracting attention.

Here, in Patent Document 3, the peripheral surfaces of the peripheral wall portions of the hollow members are brought into contact with each other, and pressure is applied from the inside of the hollow members in the contact direction to the peripheral wall portions of the hollow members that contact each other. A friction stir welding method for butt-joining hollow members is described. Further, in Patent Document 4, an aluminum hollow shape in which a front plate and a back plate are connected by a plurality of connection plates is butted against each other and between the back plates, and the front plate is attached to the butted portion. and a connecting portion for connecting between the back plates, and a joining method in which the butted portions are friction stir welded. Furthermore, in Patent Document 5, a pair of arm portions extending from each of a pair of H-shaped members toward the other H-shaped member are butted against each other, and a workpiece is pressed while being given frictional heat by a rotating tool. A method of manufacturing a mold material by friction stir welding is described, in which a fluid encapsulating body for receiving the pressing force of a rotating tool is arranged on the back surface.

JP 2010-120056 A JP 2012-170975 A Japanese Patent No. 3844835 Japanese Patent No. 4839054 JP 2008-207255 A

However, in the techniques described in Patent Documents 3 and 4, hollow members each having a connecting member capable of receiving the pressing force of the rotating tool are arranged in abutment in the vicinity of the connecting member, and the pressing force of the rotating tool is applied to the connecting member. It relates to butt welding in which friction stir welding is performed while receiving, and lap welding in which another member is superimposed on the region corresponding to the gap of the hollow material and friction stir welded is not mentioned.
Similarly, Patent Document 5 also relates to butt welding, in which friction stir welding is performed on the butt portion while receiving the pressing force of a rotating tool from a fluid encapsulating body disposed on the back side of the butt portion. However, the fluid encapsulant must be precisely arranged in accordance with the position of the abutting portion, which poses a problem from the viewpoint of work efficiency.

On the other hand, in the case of lap welding in which another member is superimposed on the outer surface of a hollow material having a void and friction stir welding is performed, a metallic hollow material having an inner void is placed on the outer surface of the hollow metal. When another member to be joined is overlapped and the joining tool is rotated and pressed against the member to be lap-welded by friction stir welding, the outer surface of the hollow member is deformed toward the inner surface side by the pressing force of the welding tool. As a result, a sufficient frictional force for softening the joint member and the hollow material cannot be obtained, and as a result, the joint strength of the joint decreases or the joint becomes impossible, so that a good friction stir weld can be obtained. I had a problem that I couldn't

The present invention has been made in view of the above-described problems, and its object is to provide a plate made of a metal material, an outer surface made of the same or different material as the plate, and an outer surface on which the plate is superimposed. Friction that can suppress deformation of the hollow material and obtain a good friction stir weld when overlapping and friction stir welding a hollow material with a closed cross section having an inner surface that is the opposite surface An object of the present invention is to provide a stir welding method and a friction stir welding apparatus.

Therefore, the above object of the present invention is achieved by the following configuration [1] relating to the friction stir welding method.

[1] A closed cross-section having a plate made of a metal material, an outer surface on which the plate is overlapped, and an inner surface opposite to the outer surface, which is made of the same or different material as the plate. A friction stir welding method for joining a hollow material,
a superposing step of superimposing the plate material and the hollow material;
a friction stir welding step of forming a friction stir weld between the plate material and the hollow material using a rotating welding tool,
In the friction stir welding step, a deformation suppression mechanism for suppressing deformation of the hollow member is provided on at least a part of the inner surface corresponding to the region where the friction stir weld is formed. Joining method.

Further, the above object of the present invention is achieved by the following configuration [2] relating to a friction stir welding apparatus.

[2] A closed cross-section having a plate made of a metal material, an outer surface on which the plate is overlapped, and an inner surface opposite to the outer surface, which is made of the same or different material as the plate. a stacking mechanism for stacking the hollow material;
a friction stir welding mechanism that forms a friction stir weld between the plate material and the hollow material using a rotating welding tool;
a deformation suppression mechanism for suppressing deformation of the hollow material in at least a partial region of the inner surface corresponding to the region where the friction stir weld is formed when the friction stir weld is formed; A friction stir welding apparatus.

According to the friction stir welding method and the friction stir welding apparatus of the present invention, the plate material is made of a metal material, and the outer surface of the plate material is made of the same or different material as the plate material, and the outer surface on which the plate material is overlapped and the side opposite to the outer surface When a hollow material with a closed cross section having an inner surface that is a plane is superimposed and friction stir welded, deformation of the hollow material is suppressed by a deformation suppression mechanism for suppressing deformation of the hollow material, and good friction stir welding is performed. It becomes possible to obtain a joint.

FIG. 1 is an explanatory view showing a friction stir welding method for joining a hollow member and a plate member according to the first embodiment of the present invention. FIG. 2 is an explanatory diagram showing a friction stir welding method for joining a hollow member and a plate member according to the second embodiment of the present invention. FIG. 3 is an explanatory diagram showing a friction stir welding method for joining a hollow member and a plate member according to a third embodiment of the present invention. FIG. 4 is an explanatory diagram showing a method for friction stir welding a hollow material and a plate material according to a fourth embodiment of the present invention. FIG. 5 is an explanatory view showing a friction stir welding method for joining a hollow material and a plate material according to a fifth embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, each embodiment of a friction stir welding method for hollow materials according to the present invention and a friction stir welding apparatus that enables lap welding by the friction stir welding method will be described in detail based on the drawings.

(First embodiment)
FIG. 1 is an explanatory view showing a friction stir welding method for hollow materials according to a first embodiment of the present invention.
The friction stir welding method according to the present embodiment includes, for example, a plate material 30 made of a metal material such as aluminum, aluminum alloy, magnesium, magnesium alloy, titanium, titanium alloy, copper, copper alloy, iron, steel, and the plate material 30 In this method, a hollow member 20 made of the same or different material and having a void portion 21 therein is joined by friction stir welding. In the present invention, the material of the hollow member 20 may be the same as or different from that of the plate as long as friction stir welding with the plate 30 made of a metal material is possible.

When the plate member 30 is of the same kind as the plate member 30, for example, when the plate member 30 is aluminum, the hollow member 20 may be made of aluminum or an aluminum alloy. That is, the term "of the same kind" as used herein includes not only completely the same material, but also metal materials having a common main component.

As for the material of the hollow member 20 when it is different from the plate member 30, for example, when the plate member 30 is aluminum, the hollow member 20 is made of a metal material having a different main component from aluminum, such as magnesium, magnesium alloy, titanium, Examples include titanium alloys, copper, copper alloys, iron and steel. As the hollow member 20, non-metallic materials such as polyethylene (PE), polypropylene (PP), ethylene-acrylic acid copolymer (EAA), polytetrafluoroethylene (PTFE), and fibers mixed with these resins are used. Examples include composites such as carbon fiber reinforced plastics (CFRP), glass fiber reinforced plastics (GFRP), and other resin materials.

The hollow member 20 is formed in a tubular shape and has a closed cross-sectional cavity 21 surrounded by partition walls 24 having a substantially rectangular cross section. The septum 24 has an outer surface 22 on its outside and an inner surface 23 opposite (ie, inside) the outer surface 22 . Then, the outer surface 22 of the hollow member 20 and the plate member 30 are joined by the friction stir welding portion 31 in the region corresponding to the void portion 21 of the hollow member 20 .

In the friction stir welding method of the present embodiment, the openings at both ends in the longitudinal direction of the void 21 of the hollow material 20 (that is, the front side and the back side of the paper surface in FIG. 1) are closed with a lid member (not shown). The air gap 21 is closed. The lid member may be welded at the opening, or may be sealed with a sealing member provided on the lid member.

Next, the plate material 30 is superimposed on the outer surface 22 of the hollow member 20 in the region corresponding to the gap 21, and placed on a mounting table (not shown). It is pressed by a pair of clamps 45 and fixed on the mounting table.

Then, the airtight space 21 is filled with a pressure fluid P composed of a liquid such as water or oil or a gas such as air, which is compressed from a pressure fluid supply mechanism (not shown). The partition wall 24 is pressed from the inside to the outside by the pressing force of . In addition, in this embodiment, the pressure fluid P constitutes the deformation suppressing mechanism 50 .

Subsequently, the welding tool 40, which is a friction stir welding mechanism, is brought into contact with the plate material 30 while being rotated. The joining tool 40 includes a shoulder portion 41 and a joining pin 42 protruding from the tip of the shoulder portion 41 . By pressing the plate member 30 while rotating the joining pin 42, the plate member 30 is softened by frictional heat and pushed. Subsequently, while forming the friction stir weld 31 between the plate member 30 and the outer surface 22 of the hollow member 20, the joining pin 42 and the plate member 30 are relatively moved to point the plate member 30 and the hollow member 20 together. Friction stir welding is performed in a shape or a line.

Here, during friction stir welding, a pressing force directed downward in FIG. Since it is supported by the pressure of the pressure fluid P filled inside, the outer surface 22 of the plate member 30 and the hollow member 20 does not bend due to the pressing force of the welding tool 40, and deformation of the hollow member 20 is suppressed. , the frictional force generated between the welding tool 40 and the plate material 30 can be ensured to be large enough to form the friction stir weld 31 .

As a result, even when the plate material 30 is superimposed on the outer surface 22 of the region corresponding to the gap 21 and friction stir welding is performed, the pressing force of the welding tool 40 is large enough to form the friction stir welding portion 31. It is possible to ensure sufficient joint strength at the joint portion. That is, the pressure fluid P filled in the space 21 acts as a deformation suppression mechanism 50 that suppresses deformation of the hollow member 20, and deformation of the outer surface 22 of the hollow member 20 is suppressed. In addition, since the deformation suppressing mechanism 50 is the pressure fluid P, the force of the same magnitude acts on all parts within the gap 21 . As a result, there is no need to select the bonding position between the plate member 30 and the hollow member 20, and the bonding can be performed at an arbitrary position, improving work efficiency.

After friction stir welding the plate material 30 and the hollow material 20, the pressure fluid P is discharged from the cavity 21 to release the pressing force of the pressure fluid P, thereby completing the friction stir welding.

(Second embodiment)
FIG. 2 is an explanatory view showing a friction stir welding method for hollow materials according to a second embodiment of the present invention.
In the friction stir welding method according to the present embodiment, instead of the pressure fluid P filled in the gap 21 described in the first embodiment, the deformation suppression mechanism 50 is a metal backing having a desired strength, for example. In this method using gold 51, friction stir welding is performed in a state in which the backing metal 51 is inserted into the void 21 of the hollow member 20. FIG.
The same reference numerals or equivalent reference numerals are given to the same parts as in the first embodiment to simplify or omit the description, and the same applies to the subsequent embodiments.

The thickness of the backing metal 51 is substantially the same as the height of the cavity 21, and it is preferable that the backing metal 51 is inserted in the cavity 21 with almost no gap, especially in the vertical direction. That is, it is preferable that the backing metal 51 is inserted in contact with the inner surface 23 of the hollow member 20 with almost no gap. However, since the backing metal 51 is inserted into and removed from the cavity 21 of the hollow member 20 , the thickness of the backing metal 51 is preferably slightly thinner than the height of the cavity 21 .

As a result, the pressing force of the welding tool 40 can be reliably supported by the backing metal 51, deformation of the outer surface 22 of the hollow member 20 is prevented, and sufficient frictional heat necessary for friction stir welding is ensured. be able to. Since the deformation suppressing mechanism 50 is the backing metal 51, deformation of the outer surface 22 of the hollow member 20 can be prevented more effectively than the pressurized fluid P described in the first embodiment.

After friction stir welding the plate material 30 and the hollow material 20, the friction stir welding is completed by removing the backing metal 51 from the space 21. FIG.

Since the parts other than the contents described above are the same as those of the friction stir welding method of the first embodiment, description thereof is omitted.

(Third embodiment)
FIG. 3 is an explanatory diagram showing a friction stir welding method for hollow materials according to a third embodiment of the present invention.
The friction stir welding method according to the present embodiment includes a backing metal 51, a non-metallic tube 52, and a pressure fluid P as a deformation suppressing mechanism 50, and a backing metal 51 and a The non-metallic tube 52 is inserted into the gap 21 together.

In the friction stir welding method of this embodiment, the thickness of the backing metal 51 inserted into the gap 21 of the hollow member 20 is considerably smaller than the vertical dimension of the gap 21 . A nonmetallic tube 52 is arranged below the backing metal 51 inserted into the cavity 21 . The nonmetallic tube 52 is a nonmetallic inflatable tube made of rubber, cloth, or the like. At the time of joining, a pressure fluid P consisting of a liquid such as water or oil or a gas such as air is placed in the nonmetallic tube 52 . By inflating the non-metallic tube 52 and pushing up the backing metal 51, the non-metallic tube 52 is brought into contact with the inner surface 23 of the hollow member 20 without gaps, and the pressing force of the welding tool 40 is supported by the backing metal 51. - 特許庁As a result, deformation of the outer surface 22 of the hollow material 20 due to the pressing force of the welding tool 40 is prevented, and the frictional force between the welding tool 40 and the plate material 30 is sufficiently large to form the friction stir weld 31. ensure that it is

Note that the thickness of the backing metal 51 is sufficient as long as it has rigidity to the extent that it is not deformed by the pressing force of the welding tool 40, and the thinner the backing metal 51, the easier it is to handle, which is preferable. The backing metal 51 and the non-metallic tube 52 may be independent from each other, but the backing metal 51 may be integrally fixed to the non-metallic tube 52, which is superior in handleability.

According to the friction stir welding method of the present embodiment, the backing metal 51 is pushed up by the expanding non-metallic tube 52 and comes into contact with the inner surface 23 of the hollow material 20 . The adhesion of is improved. Moreover, since the backing metal 51 can be made thinner and lighter than when the non-metallic tube 52 is not used, the backing metal 51 can be easily installed in the gap 21 .

Further, after the friction stir welding, the pressure fluid P is discharged from the non-metallic tube 52, so that the backing metal 51 can be easily pulled out from the space 21, thereby improving workability. Furthermore, by deforming the non-metallic tube 52, even if the shape of the cavity 21 is complicated, it can be easily dealt with.

After the plate material 30 and the hollow material 20 are joined by friction stir welding, the pressure fluid P is discharged from the nonmetallic tube 52 to release the pressing force of the pressure fluid P, and the backing metal 51 and the nonmetallic tube 52 are separated from each other. Friction stir welding is completed by withdrawing from the portion 21 .

By the way, the deformation suppressing mechanism 50 described in the third embodiment includes the backing metal 51, the non-metallic tube 52, and the pressure fluid P. However, the deformation suppressing mechanism 50 of the present invention does not necessarily include the backing metal. 51 and the non-metallic tube 52 are not required, and the backing metal 51 is not used as long as it can suppress bending of the outer surface 22 of the plate member 30 and the hollow member 20 due to the pressing force of the welding tool 40. Alternatively, the deformation suppressing mechanism 50 may be configured only with the nonmetallic tube 52 and the pressure fluid P.

Since the parts other than the contents described above are the same as those of the friction stir welding method of the first embodiment, description thereof is omitted.

(Fourth embodiment)
FIG. 4 is an explanatory view showing a friction stir welding method for hollow materials according to a fourth embodiment of the present invention.
In the friction stir welding method according to the present embodiment, the pressure fluid P, which is liquid such as water or oil, or gas such as air, is filled in the airtight gap 21 to suppress deformation of the hollow material 20. and the joining method according to the second embodiment in which deformation of the hollow member 20 is suppressed by inserting the backing metal 51 into the cavity 21 .

Specifically, a backing metal 51 having a thickness substantially equal to the height of the gap 21 and having a width narrower than the width of the gap 21 is inserted below the intended bonding position in the gap 21 . As a result, the backing metal 51 contacts the inner surface 23 of the hollow member 20 with almost no gap. However, two gaps 21 are formed on both sides of the backing metal 51 in the width direction (that is, in the lateral direction of the paper surface of FIG. 4).

Then, in the same manner as described in the first embodiment, after the openings at both ends in the longitudinal direction of the gap 21 are closed with cover members (not shown) to seal the gap 21, in the gap 21, The inner surface 23 of the portion not in contact with the backing metal 51 is pressurized by filling the pressure fluid P composed of a liquid such as water or oil or a gas such as air from a pressure fluid supply mechanism (not shown). It is supported by the pressing force of the fluid P and supported by the backing metal 51 inserted below the portion pressed by the welding tool 40 . As a result, the inner surface 23 can be supported more effectively than when the inner surface 23 of the hollow member 20 is supported only by filling the pressure fluid P. On the other hand, compared to the case where the inner surface 23 of the hollow member 20 is supported only by inserting the backing metal 51, the size of the backing metal 51 can be reduced, and the backing metal 51 can be installed in the gap 21. becomes easier.

After the plate material 30 and the hollow material 20 are joined by friction stir welding, the pressure fluid P is discharged from the space 21 to release the pressing force of the pressure fluid P, and the backing metal 51 is removed from the space 21. This completes the friction stir welding.

Since the parts other than the contents described above are the same as those of the friction stir welding method of the first embodiment, description thereof is omitted.

(Fifth embodiment)
FIG. 5 is an explanatory view showing a friction stir welding method for hollow materials according to a fifth embodiment of the present invention.
The friction stir welding method according to the present embodiment is different from the welding method according to the third embodiment in which the backing metal 51, the non-metallic tube 52, and the pressure fluid P are used as the deformation suppressing mechanism 50, and furthermore, This is a bonding method that uses the bonding method according to the first embodiment in which the pressure fluid P is filled.

According to the friction stir welding method of the present embodiment, it is possible to effectively support the inner surface 23 of the gap 21 while taking advantage of the merits described in the above embodiments, and the friction stir welding method of the present embodiment has excellent welding quality. A stir junction 31 can be formed.

After the plate material 30 and the hollow material 20 are friction stir welded, the pressure fluid P is discharged from the cavity 21 to release the pressing force of the pressure fluid P, and the pressure fluid P is discharged from the non-metallic tube 52. Then, the pressing force of the pressure fluid P is released, and the backing metal 51 and the non-metallic tube 52 are removed from the space 21, thereby completing the friction stir welding.

Since the parts other than the contents described above are the same as those of the friction stir welding method of the first embodiment, description thereof is omitted.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified, improved, etc. as appropriate. For example, the deformation suppressing mechanism 50 may support the inner surface 23 against the pressing force of the welding tool 40, and may be a pressure fluid P, a backing metal 51, a non-metallic tube 52, or a combination thereof. It is not limited to these, and other members or mechanisms that function as the deformation suppressing mechanism 50 may be used.

As described above, this specification discloses the following matters.

(1) A closed cross-section having a plate made of a metal material, an outer surface on which the plate is overlapped, and an inner surface opposite to the outer surface, which is made of the same or different material as the plate. A friction stir welding method for joining a hollow material,
a superposing step of superimposing the plate material and the hollow material;
a friction stir welding step of forming a friction stir weld between the plate material and the hollow material using a rotating welding tool,
In the friction stir welding step, a deformation suppression mechanism for suppressing deformation of the hollow member is provided on at least a part of the inner surface corresponding to the region where the friction stir weld is formed. Joining method.
According to this configuration, a plate made of a metal material, and a closed cross-section having an outer surface on which the plate is overlapped and an inner surface opposite to the outer surface, which is made of the same or different material as the plate. When the hollow material is overlapped and friction stir welded, the deformation of the hollow material is suppressed by the deformation suppression mechanism for suppressing the deformation of the hollow material, and a good friction stir weld can be obtained.

(2) The deformation suppressing mechanism seals a gap surrounded by the inner surface of the hollow material, fills the gap with a pressure fluid, and presses the inner surface by a pressing force of the pressure fluid. The friction stir welding method according to (1), which is a pressing mechanism.
According to this configuration, since the deformation suppressing mechanism is pressurized fluid, the force of the same magnitude acts on all portions within the gap. As a result, there is no need to select the bonding position between the plate material and the hollow material, and the bonding can be performed at any desired position, improving work efficiency.

(3) The friction stir welding method according to (2), wherein the pressure fluid is water or air.
According to this configuration, inexpensive water or air can be used as the pressure fluid.

(4) The friction stir welding method according to (2) or (3), wherein the pressing force of the pressure fluid is released after the friction stir welding step.
According to this configuration, while suppressing deformation of the hollow member during friction stir welding, the pressurized fluid filled in the gap can be discharged after the friction stir welding step.

(5) The deformation suppressing mechanism is a mechanism that is inserted into a gap surrounded by the inner surface of the hollow member and provided with a backing metal for suppressing deformation of the hollow member. The friction stir welding method according to .
According to this configuration, deformation of the hollow material can be suppressed by the backing metal inserted into the gap, and a good friction stir weld can be formed.

(6) The friction stir welding method according to (5), wherein the backing metal is removed after the friction stir welding step.
According to this configuration, it is possible to remove the backing metal inserted into the gap after the friction stir welding process while suppressing deformation of the hollow material during the friction stir welding process.

(7) The backing metal is inserted into the cavity surrounded by the inner surface together with the backing metal, and pressed by an expandable non-metallic tube containing pressure fluid inside, (5 ) or the friction stir welding method according to (6).
According to this configuration, the deformation of the hollow member can be suppressed by pressing the backing metal against the hollow member due to the expansion of the non-metallic tube. In addition, the backing metal can be made thin and light, and handling is facilitated.

(8) The friction stir welding method according to (7), wherein expansion of the nonmetallic tube is released and the backing metal is removed after the friction stir welding step.
According to this configuration, by canceling the expansion of the non-metallic tube, the backing metal can be easily removed from the gap, improving work efficiency.

(9) The friction stir welding method according to (7) or (8), wherein the nonmetallic tube is made of a flame-retardant material.
According to this configuration, deterioration of the nonmetallic tube due to frictional heat generated between the rotating welding tool and the plate can be suppressed.

(10) The deformation suppressing mechanism seals a gap surrounded by the inner surface of the hollow material, fills the gap with a pressure fluid, and presses the inner surface by a pressing force of the pressure fluid. (1 ) friction stir welding method described in.
According to this configuration, the deformation suppressing mechanism formed by the pressurized fluid and the backing metal can effectively prevent the deformation of the gap.

(11) The friction stir welding method according to (10), wherein after the friction stir welding step, the pressing force of the pressure fluid is released and the backing metal is removed.
According to this configuration, it is possible to remove the backing metal inserted into the gap after the friction stir welding process while suppressing deformation of the hollow material during the friction stir welding process.

(12) The backing metal is inserted into the cavity surrounded by the inner surface together with the backing metal, and pressed by an inflatable non-metallic tube containing the pressure fluid inside ( 10) or the friction stir welding method according to (11).
According to this configuration, the deformation suppressing mechanism can be configured by the non-metallic tube inserted into the gap together with the backing metal. Also, by expanding the nonmetallic tube, the backing metal can be brought into close contact with the inner surface of the cavity.

(13) The friction stir welding method according to (12), wherein expansion of the nonmetallic tube is released and the backing metal is removed after the friction stir welding step.
According to this configuration, the backing metal can be easily removed by discharging the pressure fluid from the non-metallic tube.

(14) The friction stir welding method according to (12) or (13), wherein the nonmetallic tube is made of a flame-retardant material.
According to this configuration, deterioration of the nonmetallic tube due to frictional heat generated between the rotating welding tool and the plate can be suppressed.

(15) A closed cross-section having a plate made of a metal material, an outer surface on which the plate is overlapped, and an inner surface opposite to the outer surface, which is made of the same or different material as the plate. a stacking mechanism for stacking the hollow material;
a friction stir welding mechanism that forms a friction stir weld between the plate material and the hollow material using a rotating welding tool;
a deformation suppression mechanism for suppressing deformation of the hollow material in at least a partial region of the inner surface corresponding to the region where the friction stir weld is formed when the friction stir weld is formed; A friction stir welding apparatus.
According to this configuration, a plate made of a metal material, and a closed cross-section having an outer surface on which the plate is overlapped and an inner surface opposite to the outer surface, which is made of the same or different material as the plate. When the hollow material is overlapped and friction stir welded, the deformation of the hollow material is suppressed by the deformation suppression mechanism for suppressing the deformation of the hollow material, and a good friction stir weld can be obtained.

(16) The deformation suppressing mechanism seals a gap surrounded by the inner surface of the hollow material, fills the gap with pressure fluid, and compresses the inner surface by a pressing force of the pressure fluid. At least one of a pressing mechanism and a mechanism that is inserted into the void surrounded by the inner surface of the hollow member and provided with a backing metal for suppressing deformation of the hollow member, The friction stir welding apparatus according to (15).
According to this configuration, the deformation suppressing mechanism for preventing deformation of the hollow member is composed of the pressure fluid filled in the void or the backing metal inserted into the void, thereby effectively suppressing the deformation of the hollow member. can be suppressed.

20 Hollow material 21 Cavity 22 Outer surface 23 Inner surface 24 Partition wall 30 Plate material 31 Friction stir welding part 40 Welding tool (friction stir welding mechanism)
41 shoulder portion 42 joining pin 45 clamp (superposition mechanism)
50 deformation suppression mechanism 51 backing metal 52 non-metallic tube P pressure fluid

Claims (16)

A plate material made of a metal material, and a closed-section hollow material made of the same or different material as the plate material and having an outer surface on which the plate material is superimposed and an inner surface opposite to the outer surface. A friction stir welding method for joining,
a superposing step of superimposing the plate material and the hollow material;
a friction stir welding step of forming a friction stir weld between the plate material and the hollow material using a rotating welding tool,
In the friction stir welding step, a deformation suppression mechanism for suppressing deformation of the hollow member is provided on at least a part of the inner surface corresponding to the region where the friction stir weld is formed. Joining method. The deformation suppressing mechanism seals a gap surrounded by the inner surface of the hollow member, fills the gap with a pressurized fluid, and presses the inner surface with a pressing force of the pressurized fluid. The friction stir welding method according to claim 1, wherein The friction stir welding method according to claim 2, wherein the pressure fluid is water or air. 4. The friction stir welding method according to claim 2, wherein the pressing force of said pressure fluid is released after said friction stir welding step. 2. The deformation suppressing mechanism according to claim 1, wherein the deformation suppressing mechanism is a mechanism that is inserted into a gap surrounded by the inner surface of the hollow member and provided with a backing metal for suppressing deformation of the hollow member. Friction stir welding method. The friction stir welding method according to claim 5, wherein the backing metal is removed after the friction stir welding step. 7. The backing metal is inserted into the cavity surrounded by the inner surface together with the backing metal, and pressed by an expandable non-metallic tube containing pressure fluid therein. The friction stir welding method according to . 8. The friction stir welding method according to claim 7, wherein expansion of said nonmetallic tube is released and said backing metal is removed after said friction stir welding step. The friction stir welding method according to claim 7 or 8, wherein the nonmetallic tube is made of a flame-retardant material. The deformation suppressing mechanism seals a gap surrounded by the inner surface of the hollow member, fills the gap with a pressurized fluid, and presses the inner surface with a pressing force of the pressurized fluid. , and a mechanism provided with a backing metal that is inserted into the void surrounded by the inner surface of the hollow member and suppresses deformation of the hollow member. friction stir welding method. 11. The friction stir welding method according to claim 10, wherein after the friction stir welding step, the pressing force of the pressure fluid is released and the backing metal is removed. 11. The backing metal is inserted into the cavity surrounded by the inner surface together with the backing metal, and pressed by an expandable non-metallic tube containing the pressure fluid therein. 12. The friction stir welding method according to 11. 13. The friction stir welding method according to claim 12, wherein expansion of the non-metallic tube is released and the backing metal is removed after the friction stir welding step. The friction stir welding method according to claim 12 or 13, wherein the non-metallic tube is made of a flame-retardant material. A plate material made of a metal material, and a closed-section hollow material made of the same or different material as the plate material and having an outer surface on which the plate material is superimposed and an inner surface opposite to the outer surface. a superposition mechanism for superimposing
a friction stir welding mechanism that forms a friction stir weld between the plate material and the hollow material using a rotating welding tool;
a deformation suppression mechanism for suppressing deformation of the hollow material in at least a partial region of the inner surface corresponding to the region where the friction stir weld is formed when the friction stir weld is formed; A friction stir welding apparatus. The deformation suppressing mechanism seals a gap surrounded by the inner surface of the hollow member, fills the gap with a pressurized fluid, and presses the inner surface with a pressing force of the pressurized fluid. and a mechanism provided with a backing metal that is inserted into the void surrounded by the inner surface of the hollow member and suppresses deformation of the hollow member. The friction stir welding apparatus according to 1.

Images