JP2002263863A - Friction/agitation joining tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction/agitation joining tool capable of easily forming a joining part in which burrs and internal defects or the like hardly occur. SOLUTION: The friction/agitation tool 1 is provided with a columnar tool body 2, an agitating pin 10 hanging down from the vicinity of the center of the bottom surface 3 of the tool body 2, and a backing part 14 arranged at the tip end 12 of the agitating pin 10. Spiral type projected lines 8 and 16 are arranged between the peripheral edge and the agitating pin 10 in the bottom surface 3 of the tool body 2 and the upper surface 15 of the backing part 14 facing the bottom surface 3 of the tool body 2 in the backing part 14, also a ring-shaped projected part 4 is arranged in a position nearer to the tool body 2 than the spiral type projected line 8 closer to the peripheral edge of the bottom surface 3 of the tool body 2, and moreover a recessed groove 6 which is recessed toward the tool body 2 is formed between the ring shaped projected part 4 and the spiral type projected line 8.

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 tool which is suitably used when a pair of metal members such as extruded profiles to be joined are in a cantilevered state.

[0002]

2. Description of the Related Art As shown in FIG. 7A, in order to butt-join metal plates 64 and 65 whose edges to be joined are in an unconstrained state, a friction welding tool 60 is moved along these butt surfaces 66. Used. In the joining tool 60, a stirring pin 62 and a backing plate 63 are protruded from the bottom surface of a cylindrical tool main body 61 coaxially. Friction welding tool 6
0 is a metal plate 6 which is a front-rear direction of FIG. 7 (A) while receiving a downward pushing force along the axis and rotating at a high speed.
4 and 65 move along the butting surface 66. As a result, the metal that is the material of the metal plates 64 and 65 near the butting surface 66 is stirred by the stirring pin 62 and plasticized and fluidized, so that the metal plates 64 and 65 are friction stir welded along the butting surface 66. You. During this time, backing board 6
Numeral 3 supports the fluidized metal accompanying the pushing force from below.

As shown in FIG. 7 (B), the metal plates 67 and 68 whose edges to be joined are in an unconstrained state are overlapped and joined. A similar friction welding tool 60 is used. The joining tool 60 is also applied with a downward pushing force along the axis and moves in the front-rear direction of FIG. As a result, the metal near the overlapping surface 69 is stirred by the stirring pin 62 and plasticized and fluidized, and the metal plates 67 and 68 are friction stir welded along the overlapping surface 69. During this time, the backing board 63
The metal having the pushing force and fluidized is pressed into a metal plate 68.
Is supported from below.

Further, a friction welding tool 70 as shown in FIG. 7 (C) has been proposed to simultaneously perform butt welding at two places (Japanese Patent Application Laid-Open No. H11-347775). As shown in FIG. 7 (C), the joining tool 70 includes a first stirring pin 72, a first backing plate 73, a connecting portion 74, a second backing plate 75, a bottom surface of a cylindrical tool body 71, The second stirring pin 76 and the tip presser 77 are provided coaxially.
FIG. 7 (D) shows hollow extrusions 78 and 79 made of an aluminum alloy using the friction welding tool 70 described above.
Shows the state of joining. As shown, the extruded profile 78,
Upper and lower end pieces 78a, 79a, 78b, 79 at 79
b is set in a butted state in advance.

As shown in FIG. 7D, the first and second stirring pins 72 and 76 are positioned near a pair of upper and lower abutting surfaces, and the friction welding tool 70 is rotated at a high speed. To move along the back and forth direction. As a result, the aluminum alloy (metal), which is the material of the extruded profiles 78, 79 of the butted surfaces, is agitated by the stirring pins 72, 76 and plasticized and fluidized. Friction stir welding is performed along the surface. During this time,
The first and second backing plates 73 and 75 support the fluidized aluminum alloy with the above-mentioned indenting force.

Further, a friction welding tool 80 as shown in FIG. 7E has been proposed to simultaneously perform butt welding at two places (Japanese Patent Laid-Open No. 2000-202647). As shown in FIG. 7E, the joining tool 80 includes a cylindrical tool body 81, an upwardly concave bottom surface 82 of the body 81,
It has a first stirring pin 83, a backing body 84, an upwardly concave bottom surface 85 of the backing body 84, and a second stirring pin 86 coaxially. FIG. 7 (F) shows a state in which hollow extrusion members 87 and 88 made of an aluminum alloy are butt-joined using the friction welding tool 80 as described above. As shown, the upper and lower end pieces 87 of the extruded profiles 87, 88
a, 88a, 87b, and 88b are in a state of being abutted in advance.

As shown in FIG. 7 (F), the first and second stirring pins 83, 86 are located near the pair of upper and lower butting surfaces, and the friction welding tool 80 is rotated at a high speed. To move along the back and forth direction. As a result, the metal which is the material of the extruded profiles 87 and 88 of the butted surfaces is mixed with the stirring pin 8.
The extruded members 87 and 88 are friction-stir-welded along a pair of upper and lower butted surfaces in order to be stirred and plasticized and fluidized. In the meantime, the backing body 84 supports the fluidized metal with the pushing force.

[0008]

If the amount of pushing of the friction welding tools 60, 70, 80 becomes excessive, the plasticized fluidized metal is pushed out from the bottom surface of the tool body 61 or the like, so that the abutting surfaces 66 are formed. A burr is formed along both sides of the surface of the joint formed along, or the like, and a depression on the surface of the joint becomes large. For this reason, there has been a problem that the cross-sectional area of the joining portion is smaller than the initial one, and the joining strength is reduced. On the other hand, if the pushing amount of the friction stir tool 60 or the like becomes too small,
In a joint formed along the like, the burrs and dents are reduced, but internal defects (voids) are generated due to insufficient pressing. For this reason, there is a problem that the joining strength of the joining portion is also lowered. An object of the present invention is to provide a friction stir welding tool that solves the above-described problems in the conventional technology and that can easily form a joint that is less likely to cause burrs and internal defects.

[0009]

According to the present invention, in order to solve the above-mentioned problems, an inner metal reservoir is formed around a stirring pin and an outer metal reservoir near an outer periphery thereof on a bottom surface of a tool body or the like. It was made with inspiration. That is, a first friction stir welding tool (Claim 1) of the present invention includes a column-shaped tool body, a stirring pin hanging from a bottom surface of the tool body, and a backing portion disposed at a tip of the stirring pin. A spiral ridge is disposed between a peripheral edge thereof and the stirring pin on a bottom surface of the tool body and an upper surface of the backing portion facing the bottom surface of the tool body, and On the bottom surface of the main body, a ring-shaped convex portion is disposed closer to the periphery of the tool than the spiral-shaped convex line, and the tool is located between the ring-shaped convex portion and the spiral-shaped convex line. A groove recessed toward the body is formed.

[0010] According to this, the spiral ridge of the tool body and the backing portion is inserted together with the stirring pin between the members to be joined and a pushing force is applied near the stirring pin, so that the joining between the members to be joined is performed. Internal defects can be prevented from occurring in the part. Further, the metal (material) of the member to be joined plastically fluidized and extruded by the stirring pin is provided in an inner metal pool portion located between each spiral ridge and the stirring pin on the bottom surface of the tool body or the upper surface of the backing portion. Once, a part of the metal is further pushed out and enters the outer metal pool portion which is a concave groove on the bottom surface of the tool body. In addition, the fluidized metal is pushed out to the surface level of the member to be joined by the ring-shaped convex portion on the bottom surface of the tool main body, and is hardly pushed out from the bottom surface of the tool main body to the outside, so that no burr is generated. As a result, the metal that has entered the inner / outer metal reservoir passes through the side of the stirring pin with the movement of the friction stir welding tool, and shifts to the site where the stirring pin was located immediately before. Solidifies to form a sound joint without internal defects such as voids and surface defects such as dents and burrs. Therefore, it is possible to reliably obtain a sound joint having a required joint strength.

Note that the columnar tool body includes a cylindrical shape, a regular polygonal prism (such as a quadrangular prism, a hexagonal prism, an octagonal prism), or a deformed polygonal prism. Therefore, the bottom surface of the tool body includes a circular shape, a regular polygon (such as a hexagon or an octagon), or a deformed polygon. In addition, the ring-shaped convex portion includes a shape that presents a circular shape, a polygonal shape, or a spiral shape of about one turn in a bottom view. Furthermore, the spiral ridge is spirally connected from the vicinity of the root of the stirring pin toward the concave groove of the tool main body or toward the periphery of the upper surface of the backing portion, so that one ridge is formed in one or more rounds in plan view. Or two to four ridges that are substantially less than one round in plan view and symmetrically positioned about the stirring pin. In addition, on the peripheral surface of the stirring pin, a screw portion, a plurality of narrow grooves along the axial direction, and a plurality of grooves along the direction orthogonal to the axial direction are provided in order to promote the stirring of the metal of the member to be joined. Numerous grooves, a large number of scattered projections,
Alternatively, a large number of small ridges projecting in a scattered manner and substantially parallel to the axial direction are formed.

Also, on the upper surface of the backing portion, a ring-shaped protrusion is disposed closer to the periphery than the spiral-shaped ridge, closer to the backing portion. The present invention also includes a friction stir welding tool in which a concave groove that is recessed toward the backing portion is formed between the convex ridge and the convex ridge. According to this, the metal fluidized by the stirring pin once enters the inner metal reservoir located between the spiral ridge on the upper surface of the backing portion and the stirring pin, and a part of the metal is further pushed out and backed. Into the outer metal pool portion, which is a concave groove on the upper surface of the portion. In addition, the fluidized metal is pushed and spread to the back surface level of the member to be joined and the like by the ring-shaped convex portion on the upper surface of the backing portion, and is less likely to be pushed out from the bottom surface of the tool body and the upper surface of the backing portion. For this reason, burrs are not generated, and the wall thickness in the vicinity of the joint can be maintained at about the initial thickness.

On the other hand, the second friction stir welding tool of the present invention (claim 3) has a column-shaped tool main body and a tool hanging down from the bottom surface of the tool main body or positioned substantially on an extension of the axis of the tool main body. A plurality of agitating pins, one or more backing portions having upper and lower surfaces located between the plurality of agitating pins and substantially parallel to the bottom surface of the tool body, and a lowermost end (most advanced)
A tip portion located at the tip of the stirring pin and having an upper surface substantially parallel to the bottom surface of the tool main body.The lower surface of the tool body, the upper and lower surfaces of the backing portion, and the upper surface of the tip portion have A spiral ridge is disposed between the peripheral edge of the tool and the stirring pin, and at least one of the bottom surface of the tool main body and the upper surface of the tip portion, a ring-shaped convex portion closer to the peripheral edge than the spiral ridge is provided. And a groove recessed toward the tool body or the tip portion is formed between the ring-shaped protrusion and the spiral-shaped ridge, respectively. .

According to this, each of the spiral ridges on the bottom surface of the tool body, the upper and lower surfaces of the backing portion, and the upper surface of the tip portion,
The stirrer is inserted together with the stirring pin between two or more butting surfaces of the members to be joined, and a pushing force is applied in the vicinity of each of the stirring pins. Internal defects can be prevented from occurring. Further, the metal plasticized and extruded by the plurality of stirring pins once enters the inner metal pool portion located between each spiral ridge and each stirring pin,
A part thereof is further extruded and enters each outer metal pool portion which is a concave groove on at least one of the bottom surface of the tool main body and the upper surface of the tip portion.

In addition, the fluidized metal is pushed to the front or back surface level of the member to be joined by the ring-shaped convex portions on the bottom surface and the top surface of the tip portion of the tool body, and the metal is spread from the bottom surface and the top surface of the tip portion of the tool body. Since it is difficult to be pushed out to the outside, burrs can be prevented from being generated on the front and back surfaces. As a result, the metal that entered each of the inner and outer metal reservoirs passed by one of the stirring pins along with the movement of the friction stir welding tool, and these stirring pins were located immediately before. After shifting to the site, it solidifies to form a sound joint without internal defects such as voids and surface defects such as burrs. A plurality of straight blades or the like protruding along the axial direction may be provided on the peripheral surface of the backing portion. The “upper surface” indicates a surface of the second friction stir welding tool closer to the tool body, and the “lower surface” indicates a surface closer to the front end.

Further, a column-shaped tool main body, a plurality of stirring pins which are suspended from a bottom surface of the tool main body or are located substantially on an extension of the axis of the tool main body, and a tool main body which is located between the plurality of stirring pins and which is located between the plurality of stirring pins. One or more backing portions having upper and lower surfaces substantially parallel to the bottom surface of the stirrer, and a tip portion located at the tip of the lowermost (most advanced) stirring pin and having an upper surface substantially parallel to the bottom surface of the tool body, Spiral-shaped ridges are respectively arranged between the peripheral edge and the stirring pin on the bottom surface of the tool main body, the upper and lower surfaces of the backing portion, and the upper surface of the tip portion, and the peripheral edges thereof are arranged closer to the peripheral edge. The ring-shaped protrusion is closer to the tool body than the spiral-shaped protrusion,
A tool body disposed closer to the backing portion or closer to the tip, and between the ring-shaped protrusion and the spiral-shaped ridge;
A second friction stir welding tool (Claim 4) in which a concave groove recessed toward the backing portion or the tip portion is formed is also included in the present invention.

According to this, in addition to the above-described configuration, ring-shaped convex portions and concave grooves are further formed on the upper and lower surfaces of the backing portion. Since it is spread out to the back surface or the surface level between the individual abutting surfaces, and hardly pushed out from the upper and lower surfaces of the backing portion, burrs and dents do not occur. Thus, for example, when a pair of hollow extruded sections are butt-joined at a plurality of locations, no burrs or dents are formed in the joints located inside each joint, and there is no protrusion between the extruded sections. A new hollow is obtained. Accordingly, a sound joint having a cross-sectional area and a joint strength that maintains the original thickness can be reliably and simultaneously formed in parallel at a plurality of opposed butting surfaces or overlapping surfaces. Note that the plurality of backing portions and the upper surface, the stirring pin, and the lower surface located therebetween are arranged at equal intervals or irregular intervals along the axial direction of the backing portions. Is also possible.

Further, the present invention includes a friction stir welding tool in which an inclined surface is located on the inner peripheral side of the ring-shaped convex portion or on the outer peripheral side of the concave groove adjacent thereto. According to this, the metal that has been fluidized and extruded from the inner metal reservoir portion located between each spiral ridge and the stirring pin is easily guided into each concave groove that is the outer metal reservoir portion by the inclined surface. Therefore, it is difficult for the tool body to be pushed out from the bottom surface of the tool body or the upper surface of the tip portion. Therefore, burrs on the front and back surfaces of the plurality of joints can be more reliably prevented. In addition, since the metal entering each groove is expanded stepwise with the movement of the tool, it is possible to prevent surface defects such as dents on the front / back surfaces of a plurality of joints due to poor metal expansion. Also becomes easier.

The axis of the stirring pin may be a tool for friction stir welding, wherein the axis of the stirring pin is coaxial with the tool body, the backing portion, and the tip, or deviates from any one of these axes. It is possible. In the case where the shaft center is deviated, the stirring pin itself rotates and revolves with the rotation of the tool body and the like, so that the friction stirring and flow of the metal of the member to be welded located around the stirring pin are performed. Can be further improved.

[0020]

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 relates to a first friction stir welding tool 1 according to the present invention. As shown in FIGS. 1A and 1B, the tool 1 for friction stir welding is
1, a tool body 2 having a cylindrical shape, and a tool body 2 extending from the center of a circular bottom surface 3 thereof.
Cylindrical stirring pin 10 hanging coaxially with the disk, and a disk-shaped backing portion 1 disposed at the tip (lower end) of the stirring pin 10
4 is provided. On the bottom surface 3 of the tool body 2,
A ring-shaped convex portion 4 having a circular bottom view at its peripheral edge, a concave groove 6 having a substantially triangular cross-section adjacent to the inner peripheral side and concave toward the tool body 2, and between the concave groove 6 and the stirring pin 10. And a spiral ridge 8 disposed below the cylindrical base surface 7.

As shown in FIGS. 1 (A) and 1 (B), the spiral ridge 8 is provided at the base 1 of the stirring pin 10 below the base surface 7.
It has a spiral shape in which the space between the base 1 and the peripheral edge of the base surface 7 is wound substantially one round in a bottom view, and a spiral inner metal reservoir 9 is formed between the stirring pin 10 and the spiral. On the inner peripheral side of the ring-shaped convex portion 4 and on the outer peripheral side of the concave groove 6, an inclined surface 5a that becomes higher toward the root 11 side of the stirring pin 10 is located. Further, the concave groove 6 constitutes an outer metal pool portion, and is disposed together with the ring-shaped convex portion 4 at a position higher than the spiral convex line 8 closer to the tool main body 2. On the other hand, the stirring pin 10 has a threaded portion 13 for promoting stirring between the root 11 and the tip 12. In addition, the backing portion 14 spirals around the upper surface 15 of the disc-shaped main body 18 facing the bottom surface 3 substantially one turn in a plan view between a portion near the periphery and the tip 12 of the stirring pin 10 and spirals. A spiral ridge 16 having a shape is arranged, and a metal reservoir 17 is formed between the ridge 16 and the stirring pin 10.

The spiral ridges 8, 1 facing each other vertically
6 are formed in the same direction in plan view, but the positions of the base end near the stirring pin 10 and the front end near the peripheral edge are desirably shifted to substantially opposite positions in plan view.
That is, the inner metal reservoir 9 and the metal reservoir 17 have substantially opposite phases. The bottom surface 5 of the ring-shaped convex portion 4
The distance between the base material and the upper surface 15 of the backing part 14 is set in advance so as to be substantially the same as the thickness of the material or the piece to be bonded. Further, the diameter of the stirring pin 10 is set to be substantially the same as the thickness of the material to be joined and the like.

A joining method using the friction stir welding tool 1 will be described with reference to FIGS. FIG. 2A shows, for example, JI
S: A pair of extruded members E1 and E2 made of an aluminum alloy such as A6061-T5 and having a hollow portion h therein,
A state in which the both edges e1, e2 and the edges e3, e4 are butted and restrained via the butting surfaces F, F between the edges e3, e4 is shown. As shown in FIG. 2 (B), the friction stir welding tool 1 and the axis of the tool main body 2 are formed in the vicinity of one end on the abutting surface F between the edges e1 and e2 of the extruded profiles E1 and E2. The members are placed in a vertical posture with respect to the surfaces of the members E1 and E2. At this time, the tool 1 for friction stir welding includes the tool body 2, the stirring pin 10, and the backing portion 14 at 100 to 15.
It rotates at a high speed of 00 rpm and moves at a moving speed of 0.05 to 2 m / min in the direction of the arrow in FIG. Moreover,
The tool main body 2 and the stirring pin 10 have a pressing force (pushing force) of several kN to 30 kN in the axial direction.

As shown in FIG. 2 (C), the tool 1 for friction stir welding includes a ring-shaped convex portion 4 on the bottom surface 3 of the tool body 2 on the surfaces of the edges e1 and e2 of the extruded profiles E1 and E2. With the bottom surface 5 substantially in contact with the upper surface 15 of the backing portion 14 substantially in contact with the back surfaces of the edges e1 and e2, it moves in the depth direction in the drawing while rotating. That is, the distance between the bottom surface 5 of the ring-shaped convex portion 4 and the upper surface 15 of the backing portion 14 is
It is set in advance so as to substantially match the thickness of the edges e1 and e2. As shown in FIG. 2 (C), an agitating pin 10 having a screw portion 13 and rotating at a high speed enters with a pushing force, thereby forming edges e1 and e2 near the abutting surface F. (Hereinafter referred to as metal)
It is agitated by frictional heat and becomes plastic fluidized. Further, the metal extruded to the side by the stirring pin 10 receives a downward pressing force by the spiral ridge 8 and the base surface 7. For this reason, internal defects such as voids can be reliably prevented in the joint S formed following the butting surface F.

Further, a part of the extruded metal is:
While receiving the pushing force, as shown by an arrow in FIG. 2 (C), it enters the inside metal reservoir 9 or metal reservoir 17. Further, a part of the metal extruded by the stirring pin 10 and the metal that has entered the inner metal reservoir 9 and the metal reservoir 17 are further outwardly from the abutting surface F as indicated by arrows in FIG. It is pushed and easily enters into the concave groove 6 which is the outer metal pool by the inclined surface 5a. After the metal entering the concave groove 6 passes along the rotation direction of the stirring pin 10 and the side of the stirring pin 10, the metal shifts to a portion where the stirring pin 10 was located immediately before,
It is spread and solidified stepwise by the inclined surface 5a. While performing such an operation, the joining tool 1 is configured as shown in FIG.
As shown in (B), a joint S is formed along the abutting surface F.

During this time, the metal that has come out of the concave groove (outside metal reservoir) 6 does not scatter outside the bottom surface 3 of the tool body 2. As a result, as shown in FIG. 3B, burrs along both sides of the surface s1 of the joint S can be reliably prevented, and the surface s1 of the joint S can be prevented.
No surface defects such as dents are formed in the sample No. 1. In the above joining step, since the backing portion 14 supports the back surfaces of the edges e1 and e2 from below by the upper surface 15, the metal softened and fluidized near the edges e1 and e2 due to the pushing force. The situation where e2 is pushed down is prevented.

According to the above-described tool 1 for friction stir welding, the stirring pin 10 or the like which enters the vicinity of the butt surface F between the edges e1 and e2 of the extruded profiles E1 and E2 with a required pushing force is used. The fluidized and extruded metal is
While being pressed by the spiral ridges 8 and 16, it is shifted to the rear of the stirring pin 10 through the inner / metal reservoirs 9 and 17 and the concave groove (outer metal reservoir) 6 to be solidified. Therefore, at the joint S formed along the abutting surface F, internal defects such as voids, surface defects such as dents, and burrs are not generated on both sides of the surface. The same joining is also performed between the edges e3 and e4 of the extruded profiles E1 and E2 by using the friction stir welding tool 1 upside down in FIGS. 2 (B) and 3 (A). It can be joined via the part S.

Accordingly, the extruded section E is formed through the joint S having a required cross-sectional area and having a sound and constant joint strength.
1, E2 can be securely butted and joined.
Incidentally, as shown in FIG. 3C, the upper surface 15 of the backing portion 14a is formed.
In addition, a similar ring-shaped convex portion 19 is arranged closer to the back edge portion 14a than the spiral-shaped convex portion 16 near the periphery thereof, and the ring-shaped convex portion 19 is arranged between the ring-shaped convex portion 19 and the spiral-shaped convex portion 16. Groove 15a recessed toward backing portion 14a and inclined surface 19
a may be formed. This facilitates prevention of burrs and dents on both the front and back surfaces of the joint S shown in FIG. 3B. In addition, the tool 1 for friction stir welding as described above
Is the distance between the edges e1 and e2 of the extruded profiles E1 and E2 and the edge e.
The present invention can be applied not only to the overlap joining between 3 and e4 but also to the overlap joining between flat metal members.

FIG. 4 relates to a second friction stir welding tool 20 according to the present invention. Friction stir welding tool 20
As shown in FIGS. 4 (A) and 4 (B), is an integrally formed product made of tool steel such as SKD61, and is coaxial with the main body 22 from the center of the cylindrical tool main body 22 and the circular bottom surface 23 thereof. A cylindrical first stirring pin 30a hanging down at the heart, a cylindrical backing portion 34 arranged at the tip (lower end) of the stirring pin 30a, and a second backing portion 34 hanging coaxially from the center of the backing portion 34. A stirring pin 30b and a disk-shaped tip 44 disposed at the tip of the stirring pin 30b. On the bottom surface 23 of the tool main body 22, a ring-shaped convex portion 24 having a circular bottom view at the peripheral edge thereof, a concave groove 26 having a substantially triangular cross-section adjacent to the inner peripheral side thereof and concave toward the tool main body 22 are formed. The spiral ridge 2 located between the groove 26 and the first stirring pin 30a and disposed below the cylindrical base surface 27.
8 are formed.

As shown in FIGS. 4 (A) and 4 (B), the spiral ridge 28 forms a bottom surface between the root 31 of the first stirring pin 30a and the periphery of the base surface 27 on the base surface 27. It has a spiral shape wound substantially one round, and forms an inner metal pool portion 29 between itself and the first stirring pin 30a. Further, on the inner peripheral side of the ring-shaped convex portion 24 and the outer peripheral side of the concave groove 26, a first
The inclined surface 24a which becomes higher toward the stirring pin 30a is located. Further, the concave groove 26 forms an inner metal pool portion and both the ring-shaped convex portions 24 are arranged at a position closer to the tool main body 22 than the spiral-shaped convex line 28.
The first stirring pin 30a has a screw portion 33 between the root 31 and the tip 32 for promoting stirring.

Further, the backing portion 34 has a cylindrical main body 35.
The upper surface 36 facing the bottom surface 23 of the tool body 22 at
In addition, a spiral-shaped ridge 38 that is wound substantially one turn in a plan view and has a spiral shape is disposed between the vicinity of the periphery and the base 31 of the first stirring pin 30a, and the ridge 38 and the stirring pin 30a are arranged.
To form a metal reservoir 39. Further, on the bottom surface 40 of the main body 35, a spiral-shaped ridge 42 that is wound substantially one turn and has a spiral shape is disposed between the vicinity of the periphery and the root 31 of the second stirring pin 30b, as viewed from the bottom. A metal reservoir 4 is provided between the ridge 42 and the stirring pin 30b.
3 are formed.

In addition, the tip portion 44 has a disc-shaped main body 45.
Upper surface 46 facing the bottom surface 40 of the backing portion 34
In addition, a ring-shaped convex portion 47 having a circular shape in its peripheral edge in a plan view.
A concave groove 48 having a substantially triangular cross-section adjacent to the inner peripheral side thereof and concave toward the tip end portion 44; and a cylindrical base upper surface 51 located between the concave groove 48 and the second stirring pin 30a. And a spiral-shaped ridge 50 disposed thereon. An inner metal pool 52 is formed between the spiral ridge 50 and the second stirring pin 30b. The concave groove 48 forms an outer metal reservoir, and on the inner peripheral side of the ring-shaped convex portion 47 adjacent thereto, an inclined surface 47a descending toward the distal end 32 of the second stirring pin 30b is located. ing. Further, a ring-shaped convex portion 47 and a concave groove 48 are provided.
Are located closer to the tip 44 than the spiral ridge 50. The spiral ridges 28, 3 facing up and down
8. Although the ridges 42 and 50 are formed in the same direction in plan view, the positions of the base end near the stirring pins 30a and 30b and the front end near the peripheral edge are substantially opposite positions in plan view. It is desirable that they are shifted.

A joining method using the friction stir welding tool 20 will be described with reference to FIG. FIG. 5 (A) shows a pair of extruded members E1 and E2 made of the same aluminum alloy as described above and having a hollow portion h inside, butted between the edges e1 and e2 and between the edges e3 and e4. A state where the parts are butted and restrained via F and F is shown. As shown, the butting surfaces F, between the edges e1, e2 and between e3, e4.
The tool 20 for friction stir welding is arranged near one end of F. As shown in FIG. 5A, the axes of the tool body 22 and the backing portion 34 are arranged in a vertical posture with respect to the surfaces of the profiles E1 and E2, and the edges e1 and e2 and the edges The tool 20 is arranged so that the backing portion 34 is located between e3 and e4.

At this time, as shown in FIG.
The bottom surface 25 of the ring-shaped convex portion 24 on the bottom surface 23 of the tool body 22 substantially contacts the surface (upper surface) of the tool body 22, and the upper surface 36 of the backing portion 34 on the back surface (inner surface) of the edges e1 and e2.
Are almost in contact with each other, and on the surfaces (inner surfaces) of the edges e3 and e4,
The lower surface 40 of the backing portion 34 is almost in contact with the edge e3, e
The upper surface 49 of the ring-shaped convex portion 47 on the upper surface 46 of the distal end portion 44 is almost in contact with the back surface (lower surface) of the front end 4. That is, the distance between the bottom surface 25 of the ring-shaped protrusion 24 and the upper surface 36 of the backing portion 34 and the distance between the bottom surface 40 of the backing portion 34 and the upper surface 49 of the ring-shaped protrusion 47 are determined by the edge e1. , E2 and the thickness of the edges e3, e4.

As a result, as shown in FIG.
A first stirring pin 30 is provided near the abutting surface F between the first and e2.
a is located, and the second stirring pin 30b is located near the abutting surface F between the edges e3 and e4. As shown in FIGS. 5A and 5B, the friction stir tool 20 is rotated between the edges e1 and e2 and between the edges e3 and e while being rotated at the same rotational speed as described above.
It moves in the depth direction as shown along each butting surface F between the four. At this time, a pressing force along the axial direction is applied to the tool body 22 and the backing portion 34 in the same manner as described above.

As shown in FIG. 5B, first and second stirring pins 30a and 30b having a screw portion 33 and rotating at a high speed.
However, the metal (material) forming the edges e1, e2, e3, and e4 in the vicinity of each abutting surface F is agitated by frictional heat and plastically fluidized by entering with a pushing force. The metal extruded laterally by the first and second stirring pins 30a, 30b receives a downward pushing force by the spiral ridges 28, 42, or by the spiral ridges 38, 50. Receives upward pushing force.
Therefore, internal defects such as voids can be reliably prevented in the joints S formed adjacent to the butting surfaces F.

A part of the extruded metal is
While receiving the pushing force, as shown by arrows in FIG. 5B, the inner metal pools 29 and 52 or the metal pool 39 and
43. Further, a part of the metal extruded by the first stirring pin 30a and the inner metal pool 2
The metal that has entered the metal pool 9 and the metal pool 39 is further pushed outward from the abutting surface F, as shown by the upper arrow in FIG. 5B, and is the outer metal pool of the tool body 22 by the inclined surface 24a. It easily enters the concave groove 26. The metal that has entered the concave groove 26 passes along the side of the stirring pin 30a along the rotation direction of the first stirring pin 30a, and then shifts to a portion where the stirring pin 30a was located immediately before. , Are gradually spread and solidified by the inclined surface 24a.

Further, a part of the metal extruded by the second stirring pin 30b and the metal that has entered the inner metal reservoir 52 and the metal reservoir 43 are abutted as shown by the lower arrow in FIG. 5B. It is further pushed outward from the surface F, and enters the concave groove 48 which is the outer metal pool at the tip end portion 44 by the inclined surface 47a. Such concave groove 48
After entering the metal along the rotation direction of the second stirring pin 30b, it passes through the side of the second stirring pin 30b, and then shifts to the position where the stirring pin 30b was located immediately before, while the inclined surface 47a
Spreads gradually and solidifies. While performing the above operations, the friction stir welding tool 20 forms the joints S, S along the butting surfaces F, F in FIG. 5A, as shown in FIG. 5B. .

During this time, the metal that has come out of the concave grooves (outer metal reservoirs) 26 and 48 does not scatter outside to the outside than the bottom surface 23 of the tool body 22 and the upper surface 46 of the tip end portion 44. As a result, as shown in FIG. 5B, burrs along both sides of the upper and lower joints S can be reliably prevented on the front and back surfaces of the pair of upper and lower joints S to be formed. No surface defect such as a dent is formed on the front surface of S or the back surface of the lower joint portion S. In the above joining process, the backing portion 34 is
6 supports the back surfaces (inner surfaces) of the edges e1 and e2 from below, and the lower surface 40 supports the surfaces (upper surfaces) of the edges e3 and e4 from above. For this reason, the softened and fluidized metal in the vicinity of the edges e1, e
2 and the situation where the edges e3 and e4 are deformed are suppressed.

According to the tool 20 for friction stir welding as described above, a required indenting force accompanies each of the contact surfaces F between the edges e1 and e2 and between the edges e3 and e4 of the extruded profiles E1 and E2. The metal fluidized and extruded by the first and second stirring pins 30a and 30b entering by pressing is pressed by the spiral ridges 28, 38, 42 and 50. For this reason, the metal which has received the pushing force passes through the inner metal pools 29 and 52 and the metal pools 39 and 43, and a part of the metal is a concave groove (outer metal pool) 26,
After passing through 48, it is shifted to the rear of the first and second stirring pins 30a and 30b and solidified. As a result, each butt surface F
No internal defects such as voids, surface defects such as dents, and burrs do not occur in the joints S, S formed along.

Accordingly, the extruded section E is formed via the joint S having a required cross-sectional area and having a sound and constant joint strength.
1, E2 can be securely and butt-joined at once. Incidentally, at least one of the upper surface 36 and the lower surface 40 of the backing portion 34, a ring-shaped convex portion and a concave groove similar to the above may be further formed on the peripheral edge thereof. This makes it easier to prevent surface defects such as burrs and dents on all the front and back surfaces of the plurality of joints S to be formed. Further, the tool 20 for friction stir welding is provided with the edge e in the extruded profiles E1 and E2.
The present invention can be applied not only to the overlap joining between the members 1 and e2 and between the edges e3 and e4, but also to the overlapping joining of the flat plate members to be joined.

FIG. 6A shows a pair of sandwich panels (members to be joined) P1,
The state which joins P2 along a planar direction is shown. As shown in FIG. 6 (A), the panels P1 and P2 are made of aluminum alloy metal plates m1 and m2 or metal plates m3 and m4 located on the front and back surfaces, for example, paper or metal sandwiched therebetween. It is made of a core material k such as a honeycomb core made of foil. As shown in FIG. 6 (A), the friction stir welding tool 20 is previously positioned with the first stirring pin 30a near the butting surface F between the metal plates m1 and m3 on the front side of the sandwich panels P1 and P2. The second stirring pin 30b is arranged near the abutting surface F between the metal plates m2 and m4 on the back side.

Then, as shown in FIG. 6 (A), the friction stir welding tool 20 is moved in the depth direction as shown in FIG. I do. At this time, the tool body 22 and the backing portion 3
4, a pressing force along the axial direction similar to the above is applied. As a result, the panels P1 and P2 are arranged between the metal plates m1 and m3 on the front and back surfaces and between the metal plates m2 and m2.
By the similar joints S, S formed along the abutting surfaces F, F between the m4, the members are firmly joined in the plane direction. Moreover, since there are almost no burrs or dents on the front / back surfaces of the joints S, S, the appearance is also preferable.
6A, a plurality of cutting blades extending in the axial direction are protruded on the peripheral surface of the cylindrical body 35 of the backing portion 34 of the friction stir welding tool 20. Of the cores k, k between m1 and m2 and between the metal plates m3 and m4, portions near the abutting surfaces F and F can be cut off in parallel with the joining. Thereby, it is possible to secure a space in which the backing portion 34 itself moves.

FIG. 6B is a side view showing a friction stir welding tool 20a in an application form of the tool 20. As described above, the friction stir welding tool 20a is connected to the tool body 2
2. A cylindrical first stirring pin 30a hanging from the bottom surface 23, cylindrical backing portions 34a and 34b disposed at the tip of the stirring pin 30a, and the center of the bottom surface 40 of the lower backing portion 34b. Second stirring pin 3 coaxially hanging from the part
0b, and a disk-shaped tip 44 disposed at the tip of the second stirring pin 30b. Tool body 22
On the bottom surface 23 and the upper surface 46 of the distal end portion 44, spiral ridges 28 and 50, ring-shaped convex portions 24 and 47, and not-shown grooves 26 and 48 are arranged in the same manner as described above. Also,
Spiral ridges 38 and 42 are also arranged on the upper and lower surfaces 36 and 40 of the backing portions 34a and 34b as described above.

As shown in FIG. 6B, the backing portions 34a,
A third stirring pin 3 is provided between the main bodies 35a and 35b of the second stirring pin 34b.
0c, and a lower surface 36a and an upper surface 40b sandwiching this Oc. On the lower surface 36a and the upper surface 40b, between the periphery thereof and the root or the tip of the third stirring pin 30c,
Spiral ridges 38a and 42b similar to the above are protruded. Further, a thread portion 33 similar to the above is formed on the peripheral surface of the third stirring pin 30c. The spiral ridges 38a and 42b opposed to each other in the upper and lower directions are also arranged in the same direction in plan view and substantially in opposite phases. A plurality of third stirring pins (including fourth and fifth stirring pins) 30c are provided at equal intervals or at irregular intervals along the axial direction of the main bodies 35a, 35b of the backing portions 34a, 34b. Lower surface 3
6a and the upper surface 40b can also be formed.

The tool 20a for friction stir welding as described above
6 (C) to 6 (E) show a bonding method using the method. FIG.
(C) shows a pair of extruded members E3 and E4 made of the same aluminum alloy as described above and having a hollow portion h inside, and a pair of extruded members E3 and E4 between the edges ea and ed, between edges eb and ef, and an edge ec ,
A state in which the butt is restrained via the butt surfaces F, F, F between eh is shown. As shown in FIG. 6 (D), the friction stir welding tool 20a is arranged near one end of the abutting surface F at three places between the edges ea and ed, between the edges eb and ef, and between the edges ec and eh. As shown in the drawing, the axes of the tool body 22 and the backing portions 34a and 34b are arranged in a vertical posture with respect to the surfaces of the profiles E3 and E4.
Backing portion 34 between edges ea, ed and edges eb, ef
a is located, and edges eb, ef and edges ec,
It is arranged so that the backing portion 34b is located between eh.

At this time, as shown in FIG.
The bottom surface 23 of the tool body 22 substantially contacts the surfaces (upper surfaces) of a and ed, the upper surface 36 of the backing portion 34a substantially contacts the back surfaces (inner surfaces) of the edges ea and ed, and the edges eb and ef.
The lower surface 36a of the backing portion 34a is almost in contact with the front surface (inner surface), and the backing portion 34b is on the back surface (lower surface) of the edges eb and ef.
So that the upper surface 40b of the upper surface is substantially in contact with the upper surface. Further, the edge e
The lower surface 40 of the backing portion 34b is almost in contact with the surfaces (inner surfaces) of c and eh, and the upper surface 46 of the tip portion 44 is almost in contact with the rear surfaces (lower surfaces) of the edges ec and eh. That is, the bottom surface 2
The distance between the upper surface 3 and the upper surface 36 and the distance between the lower surface 40 and the upper surface 46 substantially match the thickness of the edges ea and ed and the edges ec and eh, and the distance between the lower surface 36a and the upper surface 40b is e
It is set in advance so that the thicknesses are b and ef.

For this reason, as shown in FIG. 6D, the first to third stirring pins 30a, 30a
30b and 30c are individually located. As shown in the figure, the friction stir tool 20a is moved in the depth direction in the figure along three abutting surfaces F while rotating at the same rotational speed as described above. At this time, the tool body 22 and the backing portion 3
A pushing force along the axial direction similar to the above is applied to 4a and 34b. As a result, as shown in FIG. 6 (E), the same joints S as described above are formed individually and parallel at the same time along three butt surfaces F of the profiles E3 and E4. Accordingly, the extruded members E3 and E4 are formed between the edges ea and ed, between the edges eb and ef, and between the edges e and ef.
They are firmly joined to each other via three joining portions S along each abutting surface F between c and eh. Note that the edge ea,
Surface (exposed surface) outside of each joint S of ed and edge ec, eh
The ring-shaped convex portions 24 and 47 and the concave grooves 26 and 4
Since no burrs or depressions are formed by the action of 8, the appearance is also favorable. The lower surface 36a of the backing portion 34
On at least one of the upper surface 40b and the upper surface 40b, a ring-shaped convex portion and a concave groove similar to the above may be further formed on the peripheral edge thereof. This makes it easier to prevent surface defects such as burrs and dents on all the front and back surfaces of the three joints S to be formed.

The present invention is not limited to the embodiments described above. For example, the stirring pin 10 or the first
The second stirring pins 30a, 30b and the like are not limited to the form of hanging down coaxially from the center of the tool body 2 or the like, such as the bottom surface 3, but the form of hanging down from a position slightly eccentric from the center of the bottom surface 3 or the like. You can also. In addition, stirring pin 1
The shape such as 0 is not limited to the cylindrical shape, and may be a regular polygonal prism having four or more square poles or a deformed polygonal prism. And a stirring pin 10
In place of the screw portion 13 on the peripheral surface, a plurality of continuous narrow grooves parallel or perpendicular to the axis thereof were provided on the peripheral surface of the stirring pin 10 or the like, or a large number of scattered projections were provided. It is good also as a form. Further, the material of the metal member which is the object of the friction stir welding tool of the present invention is not limited to the aluminum alloy, but also includes copper and copper alloy, various steel materials, stainless steel, titanium alloy and the like. Alternatively, a sandwich panel having a metal plate of the above material on both sides and in the middle of the thickness direction, and sandwiching a core material such as a honeycomb core made of foamed resin or paper or metal foil between these metal plates. It is also applicable to join together structural members that sandwich aggregates such as extruded members.

[0050]

According to the first friction stir welding tool of the present invention described above, the spiral ridges of the tool body and the backing portion are inserted together with the stirring pin between the members to be welded. As a result, a pressing force is applied in the vicinity of the stirring pin, so that it is possible to prevent internal defects at the joint between the members to be joined. Further, the metal (material) of the member to be joined plastically fluidized and extruded by the stirring pin is an inner metal pool located between each of the spiral ridges and the stirring pin on the bottom surface of the tool body or the upper surface of the backing portion. Once the metal enters the part, a part of the metal is further pushed out and enters the concave groove (outside metal reservoir) on the bottom surface of the tool body. Moreover, due to the ring-shaped projection on the bottom of the tool body,
The fluidized metal is pushed and spread to the surface level of the member to be joined, and is hardly pushed out from the bottom surface of the tool body to the outside, so that no burr is generated. Therefore, the metal that has entered the inner and outer metal reservoirs is solidified sequentially to form internal joints such as voids, surface defects such as dents, and sound joints without burrs. A sound joint can be reliably obtained with strength. Further, according to the friction stir welding tool of the second aspect, the initial thickness can be reliably maintained by preventing burrs and dents on the surface on the back surface side of the joined portion where the upper surface of the backing portion is in contact.

On the other hand, according to the second friction stir welding tool of the present invention (Claim 3), each of the spiral ridges on the bottom surface of the tool body, the upper and lower surfaces of the backing portion, and the upper surface of the tip portion, A stirrer pin is inserted between a plurality of butted surfaces of the members to be joined together with the stirrer pin, and a pushing force is applied near each of the stirrer pins. For this reason, it is possible to prevent an internal defect in a joint formed between a plurality of abutting surfaces. In addition, the fluidized metal is pushed out to the level of the front or back surface of the member to be joined by the ring-shaped convex portions on the bottom surface and the top surface of the tool body, and is pushed out from the bottom surface and the top surface of the tool body to the outside. Because it is difficult to
No burr occurs. Therefore, a sound joint having a required cross-sectional area and joint strength can be obtained at a plurality of places at the same time.

Further, according to the friction stir welding tool of the fourth aspect, it is possible to simultaneously form a plurality of joints at the above-mentioned joints and without any burrs or depressions inside. Furthermore, according to the friction stir welding tool of claim 5,
The metal that has been fluidized and extruded from the inner metal reservoir located between the spiral ridge and the stirring pin is easily guided into the concave groove (outer metal reservoir) by the inclined surface. It is less likely to be pushed out from the bottom or the top of the tip. Therefore, burrs on the front surface and the back surface of the joint can be more reliably prevented. In addition, the metal entering each groove is spread stepwise by the movement of the tool by the adjacent inclined surface, so that the surface like a dent on the front and back of the joint due to poor metal spreading. Defects can be easily prevented.

[Brief description of the drawings]

FIGS. 1A and 1B are perspective views or vertical sectional views showing a first friction stir welding tool.

2 (A) to 2 (C) are schematic diagrams showing a use state of the tool of FIG. 1;

FIG. 3 (A) is a schematic diagram showing a use state following FIG. 2 (C),
(B) is a cross-sectional view at a viewing angle along the line BB in (A),
FIG. 2C is a cross-sectional view showing a modification of the backing portion of the tool in FIG.

FIGS. 4A and 4B are side views or vertical cross-sectional views showing a second friction stir welding tool.

FIGS. 5A and 5B are schematic diagrams showing a use state of the tool of FIG. 4;

6A is a schematic view showing a different use state of the tool of FIG. 4; FIG. 6B is a side view showing an application form of the tool of FIG. 4;
(C)-(E) is a schematic diagram showing the use state of the tool of (B).

7A to 7F are schematic views showing a conventional friction welding tool and a method of using the same.

[Explanation of symbols]

1,20,20a ………………………………………………………………………………………………………………………………………………… Tool body 3,23 ……… ………………………………………………………………………………………………………………………………………………………………………………………………………………………………. 48 ... groove ... 28, 38, 42, 38a, 42b, 50 ... spiral ridge 10, 30a, 30b, 30c ... stirring pin 14, 14a, 34, 34a , 34b Backing part 15, 36, 40b, 46 ... Upper surface 36a, 40 ... Lower surface 44 ... ………………… Tip

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shinya Makita 1-34-1 Kambara, Kambara-cho, Anbara-gun, Shizuoka Prefecture Nippon Light Metal Co., Ltd. Group Technology Center F-term (reference)

Claims (5)

[Claims] 1. A tool body comprising: a column-shaped tool body; a stirring pin hanging down from a bottom surface of the tool body; and a backing portion disposed at a tip of the stirring pin. On the upper surface opposed to the bottom surface of the tool main body, spiral-shaped ridges are respectively arranged between the peripheral edge and the stirring pin. On the bottom surface of the tool main body, a ring-shaped convex portion is provided near the peripheral edge. A groove that is disposed closer to the tool body than the spiral-shaped ridge and that is recessed toward the tool body between the ring-shaped convex portion and the spiral-shaped ridge. And a tool for friction stir welding. 2. The upper surface of the backing portion is also provided with a ring-shaped convex portion near the periphery thereof, closer to the backing portion than the spiral-shaped ridge, and the ring-shaped convex portion and the spiral The friction stir welding tool according to claim 1, wherein a concave groove that is recessed toward the backing portion is formed between the tool and the ridge. 3. A tool body having a columnar shape, a plurality of stirring pins hanging down from a bottom surface of the tool body, or positioned substantially on an extension of an axis of the tool body, and a tool body located between the plurality of stirring pins. One or more backing portions having upper and lower surfaces substantially parallel to the bottom surface of the tool body, and a tip portion located at the tip of the lowermost stirring pin and having an upper surface substantially parallel to the bottom surface of the tool body, On the bottom surface of the tool body, the upper and lower surfaces of the backing portion, and the upper surface of the tip portion, a spiral ridge is arranged between the peripheral edge thereof and the stirring pin. On at least one of the upper surfaces, a ring-shaped convex portion is disposed closer to the periphery of the tool than the spiral-shaped convex line closer to the tool body or to the tip portion, and between the ring-shaped convex portion and the spiral-shaped convex line. Tool book Or groove recessed in the tip direction are formed, the tool for friction stir welding, characterized in that. 4. A column-shaped tool main body, a plurality of stirring pins which are suspended from a bottom surface of the tool main body or located substantially on an extension of an axis of the tool main body, and are located between the plurality of stirring pins and the tool main body. One or more backing portions having upper and lower surfaces substantially parallel to the bottom surface of the tool body, and a tip portion located at the tip of the lowermost stirring pin and having an upper surface substantially parallel to the bottom surface of the tool body, On the bottom surface of the tool body, on the upper and lower surfaces of the backing portion, and on the upper surface of the tip portion, spiral ridges are respectively arranged between the peripheral edge and the stirring pin, and ring-shaped convex portions are provided near the peripheral edge. The part is disposed closer to the tool body than the spiral ridge, closer to the backing part, or closer to the tip, and between the ring-shaped convex part and the spiral ridge, the tool body, the backing part, or Concave toward tip A friction stir welding tool, wherein a concave groove is formed in each of the grooves. 5. An inclined surface is located on an inner peripheral side of the ring-shaped convex portion or an outer peripheral side of a concave groove adjacent to the ring-shaped convex portion. Tool for friction stir welding.