JP2010137268A - Friction stir joining method, method of manufacturing cylindrical body and cylindrical body, and method of manufacturing hollow body and hollow body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a friction stir joining method capable of suppressing generation of joining trash, also to provide a method of manufacturing a cylindrical body and the cylindrical body, and further to provide a method of manufacturing a hollow body and the hollow body. <P>SOLUTION: When an overlap margin of a step part 5 and a thin member 2 to be joined is made to be L and a radius of a rotating body 4 is made to be D, the relation of L≤D is made to be satisfied. A protrusion 10 is formed at a corner between the tip of the step part 5 and the other face in the thickness direction of the thin member 2 to be joined during friction stir joining. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a friction stir welding method, a cylindrical body manufacturing method and a cylindrical body, a hollow body manufacturing method, and a hollow body.

Conventionally, the technique of patent document 1 is known as a friction stir welding method, the manufacturing method and cylindrical body of a cylindrical body, the manufacturing method of a hollow body, and a hollow body.
According to the present invention, the abutting portion that abuts each other is formed on one surface in the thickness direction of the thick-joined member and the thin-joined member having different thicknesses, and the abutting portion side end of the thick-joined member is formed. A stepped shape is integrally formed, and a thin member to be joined is disposed on one surface in the thickness direction of the step.
Then, after the rotating body is rotated and embedded in the contact portion, the contact portions are friction stir welded by moving both of them relative to each other along the contact portion.
JP-A-2005-324251

However, in the conventional invention, there is a problem in that joining scraps (so-called burrs) are generated on the joining surfaces of both the joined members during the friction stir welding.
The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to provide a friction stir welding method, a cylindrical body manufacturing method and a cylindrical body, a hollow body manufacturing method, and a hollow body. It is to be.

  According to the first aspect of the present invention, an abutting portion that abuts each other is formed on one surface in the thickness direction of the thick-walled member and the thin-walled member having different thicknesses, and the abutting portion side of the thick-walled member After forming a stepped stepped portion integrally at the end, placing the thin-walled member on one side in the thickness direction of the stepped portion, rotating the rotating body and embedding it in the contact portion In the method of friction stir welding the corresponding contact parts by relatively moving both of them along the contact part, L is the overlap amount of the stepped part and the thin member to be joined, and the radius of the rotating body is D. In this case, L ≦ D, and a convex portion is formed at the corner between the tip of the stepped portion and the other surface in the thickness direction of the thin-walled member at the time of the friction stir welding.

  According to a third aspect of the present invention, an abutting portion that abuts each other is formed on the outer peripheral surface of the cylindrical thick to-be-joined member and the thin to-be-joined member having different thicknesses. Stepped-shaped stepped portions are integrally formed on the side end portions, and the thin-walled members to be stacked are arranged outside the stepped portions, and the rotating body is rotated to be embedded in the contact portions. In the method of manufacturing a cylindrical body that frictionally stir welds the contact portion by moving both relative to each other along the abutting portion, the overlapping margin of the stepped portion and the thin-walled member is L, the rotating body In the case where the radius is D, L ≦ D, and at the time of the friction stir welding, a convex portion is formed at the corner between the tip of the stepped portion and the inner peripheral surface of the thin-walled member. .

  According to a fourth aspect of the present invention, a cylindrical body is manufactured by the manufacturing method according to the third aspect.

  In the invention according to claim 5, the abutting portion that abuts each other is formed on the outer peripheral surface of the bottomed cylindrical thick-walled member and the thin-walled member having different side wall thicknesses, and the thick-walled member A stepped shape step is integrally formed at the end of the contact portion side, and the thin member to be joined is placed outside the step, and the rotating body is rotated to be embedded in the contact portion. Then, in the manufacturing method of the hollow body that friction stir welds the contact portion by moving both of them relative to each other along the contact portion, the overlap margin between the stepped portion and the thin-walled member is L, When the radius of the rotating body is D, L ≦ D, and convex portions are formed at the corners between the tip of the stepped portion and the inner peripheral surface of the thin-walled member during the friction stir welding. It is said.

  The invention according to claim 6 is a hollow body manufactured by the manufacturing method according to claim 5.

In this invention, L ≦ D, where L is the overlap allowance between the stepped portion and the thin-walled member and D is the radius of the rotating body.
Thereby, at the time of friction stir welding, convex portions can be formed at the corners between the tip end portion of the stepped portion and the other side in the thickness direction of the thin-walled member, and the friction stir welding method capable of suppressing the generation of joining waste and the production of the cylindrical body A method, a cylindrical body, a hollow body manufacturing method, and a hollow body can be realized.

  Embodiments of the present invention will be described below with reference to the drawings.

Example 1 will be described below.
FIG. 1 is a perspective view for explaining the arrangement of a meat-to-be-joined member, a thin-walled to-be-joined member, a support member, and a rotating body in the friction stir welding method of Example 1, FIG. 2 is a cross-sectional side view, and FIGS. It is a figure explaining the friction stir welding method of Example 1. FIG.

First, the overall configuration will be described.
As shown in FIGS. 1 and 2, the friction stir welding method according to the first embodiment includes a thick-walled member 1 and a thin-walled member 2, a support member 3, and a rotating body 4.

  The thick-walled member 1 is made of metal and is formed in a flat plate shape that is thicker than the thin-walled member 2, and a stepped step portion 5 is formed at the end 1 a of the thick-walled member 1. 1 is formed integrally along the longitudinal direction.

The thin-walled member 2 is made of metal and formed thinner than the thick-walled member 1, and its end 2a is combined with the upper surface of the step portion 5 so as to form a lap joint.
As a result, the abutting portions 6 that abut each other on the upper surfaces of the members to be bonded 1 and 2 are formed in the longitudinal direction of the members to be bonded 1 and 2.

  Further, the support member 3 is brought into contact with the lower surface including the step portion 5 and its periphery along the longitudinal direction of the step portion 5, thereby supporting the step portion 5 from below.

The rotating body 4 includes a substantially cylindrical shoulder portion 7 and a substantially cylindrical probe portion 8 coupled to the lower end portion of the shoulder portion 7 and having a smaller diameter than the shoulder portion 7.
Further, a material leveling portion 7a composed of an inclined surface having a diameter reduced toward the lower side is formed on the outer peripheral portion of the lower end of the shoulder portion 7 as in the known Japanese Patent Application Laid-Open No. 2003-290937. ing.
On the other hand, the upper end portion of the shoulder portion 7 is connected to a rotation shaft of a rotation motor (not shown) via a spindle (not shown).
Thus, the rotating body 4 is provided so as to be rotatable in the direction around the axis by the driving operation of the rotating motor.
Further, the upper end side of the rotating body 4 (both the rotating motor and the spindle) is disposed at one end portion of an industrial robot arm (not shown) that can freely displace the orientation and position of the shoulder portion 7 (probe portion 8). Yes.
The driving operations of the rotation motor and the industrial robot arm are controlled by a control unit (not shown) that is electrically connected thereto.

  Further, when the overlap margin between the stepped portion 5 and the thin-walled member 2 is L, and the radius of the rotating body 4 (the radius of the shoulder portion 7) is D, L ≦ D is set.

Next, the operation will be described.
[About friction stir welding]
In order to join the contact portions 6 of the members 1 and 2 to be joined, first, as shown in FIGS. 1 and 2, the industrial robot arm is driven by the command signal from the control unit, and the rotating body 4 The probe portion 8 is disposed immediately above the joining start position of the contact portion 6.

  Next, the rotation motor is driven to rotate by the command signal from the control unit, and the rotating body 4 is rotated in the direction of the arrow X1 in FIG.

Next, as shown in FIG. 3, the industrial robot arm is driven by the command signal from the control unit to lower the rotating body 4 and slide the probe portion 8 to the contact portion 6.
Along with this sliding contact, frictional heat is generated, and the vicinity of the sliding contact portion of the probe portion 8 in the contact portion 6 is softened and spreads while plastic flowing.

Next, as shown in FIG. 4, when the industrial robot arm is driven by the command signal from the control unit to further lower the rotating body 4, the probe unit 8 and the shoulder unit 7 (both the material leveling unit 7a) are driven. Is inserted into the plastic flow region of the contact portion 6 (illustrated by broken line hatching in the figure).
By inserting the probe portion 8 and the shoulder portion 7, the plastic flow region is further agitated and widened, and at the same time, the corner portion 9 between the tip portion 5 a of the step portion 5 and the lower surface of the thin-walled member 2 (FIG. 2, 3), the protruding portion 10 is formed in which the surplus portion around the corner 9 is deformed and protruded.

Next, as shown in FIG. 5, the industrial robot arm is driven by the command signal from the control unit to rotate the rotating body 4 in the arrow X1 direction, and joins in the arrow direction X2 along the contact portion 6. It is moved over a predetermined length to be used.
The contact portion 6 through which the rotating body 4 has passed is cooled and hardened by natural cooling (or forced cooling) and solid-phase bonded. As a result, the contact portion 6 can be bonded over a predetermined length.
Moreover, the convex part 10 is also formed over predetermined length.

Thereafter, as shown in FIG. 6, the industrial robot arm is driven by the command signal from the control unit to raise the rotating body 4 from the joined members 1 and 2 and then return to the initial position.
In addition, smooth movement can also be enabled by moving the rotating body 4 in a state tilted by a predetermined angle in a direction opposite to the traveling direction.
Moreover, in Example 1, although the rotary body 4 is moved to the advancing direction with respect to the contact part 6, both should just move relatively.

[About joining waste]
In the first embodiment, as described above, L ≦ D, where L is the overlap margin between the stepped portion 5 and the thin-walled member 2 and D is the radius of the rotating body 4 (the radius of the shoulder portion 7). It is set as follows.
At the time of friction stir welding, a convex portion 10 is formed at the corner portion 9 between the tip end portion of the step portion 5 and the lower surface of the thin-walled member 2 to be deformed and protruded from the surplus portion around the corner portion 9. ing.
Thereby, it can prevent that the contact | abutting part 6 which the plastic flow area flowed rose to a joining surface, and becomes joining waste (what is called a burr | flash), and can suppress generation | occurrence | production of joining waste.
When L> D, the surplus portion of the peripheral portion of the corner portion 9 cannot be escaped as desired, so that the convex portion 10 cannot be formed and joining waste is generated.

[Moldability of convex part]
In the first embodiment, since the step portion 5 is supported by the support member 3 from below, there is no possibility that the step portion 5 hangs downward and is deformed, and thus it is stable regardless of the material and thickness of the step portion 5. Thus, the convex portion 10 can be formed.

[About material leveling section]
In Example 1, since the material leveling part 7a is formed in the shoulder part 7, like the well-known Unexamined-Japanese-Patent No. 2003-290937, the material leveling part 7a and the upper surface of the thin-walled to-be-joined member 2 are approached very much. It is possible to suppress the generation of joining waste.
In addition, you may form in the shape where the inside of the material leveling part 7a of the rotary body 4 was dented similarly to the thing of well-known Unexamined-Japanese-Patent No. 2001-205454.
At this time, in the present invention, since generation of joining scraps can be suppressed, the radial width of the material leveling portion 7a may be set to a value smaller than 2 mm.
Further, the material leveling portion 7a can be omitted, and in this case, the shape of the rotating body 4 can be simplified as compared with the conventional invention.

Next, effects of the first embodiment will be described together with (1) and (2) corresponding to claims 1 and 2.
(1) A contact portion 6 that abuts each other is formed on the upper surfaces of the thick-walled member 1 and the thin-walled member 2 having different thicknesses, and a stepped shape is formed on the end 1a of the thick-walled member 1. The part 5 is integrally formed, and the thin-walled member 2 is placed on the upper surface of the stepped part 5, and the rotating body 4 is rotated and embedded in the contact part 6. In the method of friction stir welding the corresponding contact portion 6 by relative movement along L, when the overlap margin of the stepped portion 5 and the thin-walled member 2 is L and the radius of the rotating body 4 is D, L In the friction stir welding, the convex portion 10 was formed at the corner portion 9 between the tip portion of the stepped portion 5 and the lower surface of the thin-walled member 2 during friction stir welding.
Thereby, generation | occurrence | production of joining waste can be suppressed.

(2) The step portion 5 was supported by the support member 3 from the other side in the thickness direction.
Thereby, there is no possibility that the step part 5 may hang down and deform | transform, and it can form the convex part 10 stably irrespective of the raw material and thickness of the step part 5, and the moldability of the convex part 10 is good.

Example 2 will be described below.
In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, the description thereof will be omitted, and only the differences will be described in detail.

  7-9 is a figure explaining the manufacturing method of the cylindrical body of Example 2. FIG.

  As shown in FIGS. 7 and 8, in the second embodiment, the thick-walled member 1 and the thin-walled member 2 described in the first embodiment are replaced with the cylindrical thick-walled member 20 and the thin-walled member having different thicknesses. 21, contact portions 22 are formed on the outer peripheries of the joined members 1 and 2.

  As shown in FIG. 9, the cylindrical body 23 is formed by performing friction stir welding while moving the rotating body 4 over the entire circumference of the contact portion 22 in the embodiment. Different from 1.

In the second embodiment, the support member 3 can be omitted by forming the stepped portion 5 (thick member 1) thicker than the first embodiment.
Alternatively, the support member 3 may be omitted by making the material of the stepped portion 5 (thick welded member 1) super hard.
In the second embodiment, both the members to be joined 1 and 2 are formed in a cylindrical shape, but may be formed in a cylindrical shape having a polygonal cross section or an elliptical cross section.
Further, in the second embodiment, the rotating body 4 is moved with respect to the contact portion 22, but both of them may be moved relative to each other.

Next, the effect of the second embodiment will be described together with (3) corresponding to claims 3 and 4.
(3) A contact portion 22 that abuts each other is formed on the outer peripheral surfaces of the thick-walled member 20 and the thin-walled member 21 having different thicknesses, and the abutting portion 22 side end of the thick-walled member 21 is formed. The stepped portion 5 is integrally formed, and the thin-walled member 21 is placed on the outside of the stepped portion 5, and the rotating body 4 is rotated and embedded in the contact portion 22. In the manufacturing method of the cylindrical body 23 in which the contact portion 22 is friction stir welded by relatively rotating and moving along the contact portion 22, the overlap margin of the stepped portion 5 and the thin-walled member 21 is rotated by L. When the radius of the body 4 is D, L ≦ D, and the convex portion 10 is formed at the corner portion 9 between the tip portion of the stepped portion 5 and the other surface in the thickness direction of the thin-walled member 21 during friction stir welding.
Thereby, in addition to the effect | action and effect of (1), the cylindrical body 23 can be obtained by carrying out friction stir welding of both the cylindrical to-be-joined members 20 and 21, respectively, suppressing generation | occurrence | production of joining waste.

Example 3 will be described below.
In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, the description thereof will be omitted, and only differences will be described in detail.

10 to 12 are diagrams for explaining a method for producing a hollow body of Example 3, FIG. 13 is an enlarged sectional view for explaining a method for producing a conventional hollow body, and FIG. 14 is a diagram for explaining a method for producing a hollow body of Example 3. It is an expanded sectional view explaining.
It is.

  As shown in FIGS. 10 and 11, in the second embodiment, the thick-walled member 1 and the thin-walled member 2 described in the first embodiment are different from the thick-walled member 30 in the shape of a bottomed cylinder having different side wall thicknesses. A thin-walled member 31 is formed, and a contact portion 32 is formed on the outer periphery of both the members to be bonded 1 and 2.

  And as shown in FIG. 12, the point which forms the hollow body 33 by carrying out friction stir welding, moving the rotary body 4 over the perimeter of the contact part 22 differs from Example 1. FIG.

In Example 3, the support member 3 can be omitted by forming the step portion 5 (thick member 1) to be somewhat thick.
Alternatively, the support member 3 may be omitted by making the material of the stepped portion 5 (thick welded member 1) super hard.
In the third embodiment, both the joined members 1 and 2 have a bottomed cylindrical shape, but may be formed in a bottomed polygonal cylindrical shape or an elliptical cylindrical shape, but are not limited thereto.
Furthermore, in the third embodiment, the rotating body 4 is moved with respect to the abutting portion 32. However, it is sufficient that both of them rotate relative to each other.

Here, when the hollow body 33 is formed with L> D as in the prior art, as shown in FIG. 13, bonding is performed from the vicinity of the end of the shoulder portion 7 of the rotating body 4 in the thin member 31 to be contacted. As the scrap is discharged and scraped off, a large step 34 is formed.
Since the thickness H1 of the thin-walled member 31 in the vicinity of the stepped portion 34 becomes small, there is a problem in that the stress concentrates on the position 35 and the durability of the hollow body 33 is lowered.
In addition, this problem becomes remarkable especially when a pressure is applied to the inside of the hollow body 33, and the pressure resistance of the hollow body 33 is lowered.

On the other hand, in Example 3, as shown in FIG. 14, the vicinity of the portion 36 together with the convex portion 10 gently protrudes downward to prevent the above-described large step 34 from being formed. The smoothed connecting portion 37 can be formed by the leveling portion 7a.
Thereby, the thickness of the thin-walled member 31 is not reduced, stress concentration on a specific part can be avoided, and durability and pressure resistance can be improved.
Note that the effect of avoiding stress concentration in the vicinity of the portion 35 can be similarly obtained in the first and second embodiments.

Next, the effect of Example 3 will be described together with (4) corresponding to claims 5 and 6.
(4) Abutting portions 32 that abut each other are formed on the outer peripheral surfaces of the bottomed cylindrical thick-walled member 30 and the thin-walled member 31 having different side wall thicknesses. A stepped shape step portion 5 is integrally formed at the end portion of the contact portion 32, and a thin-walled member 31 is disposed on the outside of the step portion 5, and the rotating body 4 is rotated to contact portion 6. In the method of manufacturing the hollow body 33 in which the contact portion 32 is friction stir welded by relatively rotating the two along the contact portion 32 after being embedded, the step portion 5 and the thin-walled member 31 are connected to each other. When the overlap margin is L and the radius of the rotating body 4 is D, L ≦ D, and at the time of friction stir welding, the protrusion 9 protrudes at the corner 9 between the tip of the stepped portion 5 and the other surface in the thickness direction of the thin-walled member 31. Part 10 was formed.
Thereby, while suppressing generation | occurrence | production of joining waste, both the bottomed cylindrical to-be-joined members 30 and 31 can be friction-stir-joined, and the hollow body 33 can be obtained.

Although the embodiments have been described above, the present invention is not limited to the above-described embodiments, and design changes and the like within the scope not departing from the gist of the present invention are included in the present invention.
For example, in Example 1, the traveling side in which the moving direction along the contact portion 6 of the rotating body 4 (in the direction of arrow X2 in FIG. 1) coincides with the forward direction of rotation of the rotating body 4 (in the direction of arrow X1 in FIG. 1). However, this is not necessarily the case.
That is, the generation position and shape of the joining scrap are the inclination direction, the inclination angle, the rotation operation (forward rotation, reverse rotation, or alternate rotation of normal rotation and reverse rotation), the movement direction (linear, curved), and Since it varies depending on various conditions such as the movement operation (reciprocating motion) and the state of the contact portion (flat, curved surface), the arrangement direction of the thin-walled member 2 and the operation of the rotating body are optimal in order to suppress the generation of joining debris. Any combination that is simply specified falls within the scope of this invention.

In the second and third embodiments, the outer peripheral surface of the stepped portion 5 and the inner peripheral surface of the thin-walled member 21 (31) are screwed together, and the contact portion 22 (32) is similarly friction stir welded. good.
In this case, both the members to be joined 20, 21 (30, 31) can be positioned by screwing them together, so that a jig for positioning and temporarily fixing both of them can be omitted, and stable friction stir welding and firmness can be achieved. Can be fixed.
In addition, in the case of the hollow body 33, the internal sealing degree (pressure resistance) can be improved by screwing the members to be joined 20, 21 (30, 31).

It is a perspective view explaining arrangement | positioning of the to-be-joined member and thin-walled to-be-joined member of the friction stir welding method of Example 1, a supporting member, and a rotary body. It is a sectional side view explaining arrangement | positioning of the to-be-joined member of the friction stir welding method of Example 1, a thin to-be-joined member, a supporting member, and a rotary body. It is a figure explaining the friction stir welding method of Example 1. FIG. It is a figure explaining the friction stir welding method of Example 1. FIG. It is a figure explaining the friction stir welding method of Example 1. FIG. It is a figure explaining the friction stir welding method of Example 1. FIG. It is a figure explaining the manufacturing method of the cylindrical body of Example 2. FIG. It is a figure explaining the manufacturing method of the cylindrical body of Example 2. FIG. It is a figure explaining the manufacturing method of the cylindrical body of Example 2. FIG. It is a figure explaining the manufacturing method of the hollow body of Example 3. FIG. It is a figure explaining the manufacturing method of the hollow body of Example 3. FIG. It is a figure explaining the manufacturing method of the hollow body of Example 3. FIG. It is an expanded sectional view explaining the manufacturing method of the conventional hollow body. 6 is an enlarged cross-sectional view illustrating a method for manufacturing a hollow body of Example 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 20, 30 Thick to-be-joined member 1a, 2a End part 2, 21, 31 Thin-wall to-be-joined member 3 Support member 4 Rotating body 5 Step part 6, 22, 32 Contact part 7 Shoulder part 7a Material leveling part 8 Probe part 9 Corner part 10 Convex part 23 Cylindrical body 33 Hollow body 34 Step part 35 Part 36 Part 37 Connection part

Claims (6)

On the one side in the thickness direction of the thick-walled member and the thin-walled member having different thicknesses, a contact portion that abuts each other is formed,
A stepped shape step portion is integrally formed at the abutting portion side end of the thick-walled member, and the thin-walled member is placed on one side in the thickness direction of the step portion,
In a method of rotating the rotating body and embedding it in the abutting portion, and then relatively moving these both along the abutting portion, the friction stir welding of the corresponding abutting portion,
When the overlap margin between the stepped portion and the thin-walled member is L, and the radius of the rotating body is D, L ≦ D,
The friction stir welding method, wherein a convex portion is formed at a corner between the tip end portion of the stepped portion and the other surface in the thickness direction of the thin-walled member during the friction stir welding. In the friction stir welding method according to claim 1,
A friction stir welding method, wherein the step is supported by a support member from the other side in the thickness direction. On the outer peripheral surface of the cylindrical thick-walled member and the thin-walled member having different thicknesses, a contact portion that abuts each other is formed,
A stepped shape step is integrally formed on the abutting portion side end of the thick-walled member, and the thin-walled member is placed on the outside of the stepped portion,
In the manufacturing method of the cylindrical body for friction stir welding the corresponding contact portion by rotating the rotating body and embedding in the contact portion, and by relatively rotating these both along the contact portion,
When the overlap margin between the stepped portion and the thin-walled member is L, and the radius of the rotating body is D, L ≦ D,
A method for producing a cylindrical body, wherein a convex portion is formed at a corner between the tip end portion of the stepped portion and the inner peripheral surface of the thin-walled member at the time of the friction stir welding.   A cylindrical body manufactured by the manufacturing method according to claim 3. On the outer peripheral surface of the bottomed cylindrical thick to-be-joined member and the thin-walled to-be-joined member having different side wall thicknesses, a contact portion that abuts each other is formed
A stepped shape step is integrally formed on the abutting portion side end of the thick-walled member, and the thin-walled member is placed on the outside of the stepped portion,
In the method for manufacturing a hollow body for rotating the rotating body and embedding it in the abutting portion, and then relatively moving these both along the abutting portion, the friction stir welding of the corresponding abutting portion,
When the overlap margin between the stepped portion and the thin-walled member is L, and the radius of the rotating body is D, L ≦ D,
A method of manufacturing a hollow body, wherein a convex portion is formed at a corner portion between the tip end portion of the stepped portion and the inner peripheral surface of the thin-walled member at the time of the friction stir welding.   A hollow body produced by the production method according to claim 5.

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