JP6090186B2 - Friction stir welding method - Google Patents

Description

  The present invention relates to a friction stir welding method.

  Patent Document 1 discloses a technique for friction stir welding by inserting an inner corner friction stir welding rotary tool into the inner corners of two metal members that are abutted at right angles. FIG. 13 is a cross-sectional view showing a conventional friction stir welding method. In the conventional friction stir welding method, friction stir welding is performed by the inner corner friction stir welding rotary tool 110 at the butted portion J formed by abutting the end surface of the metal member 101 and the side surface of the metal member 102.

  The inner corner friction stir welding rotary tool 110 includes a pressing block 111 that has a triangular prism shape, and a stirring pin 112 that can rotate with respect to the pressing block 111 while passing through the pressing block 111. When joining, the stirring pin 112 is rotated in a state where the pressing block 111 is in contact with the side surfaces of the metal members 101 and 102.

JP-A-11-320128

  In the conventional friction stir welding, since the presser block 111 is joined to the metal members 101 and 102 while being pressed, the metal members 101 and 102 may be scraped by the presser block 111. If the friction stir welding is performed in a state where the holding block 111 is omitted, the plastic fluidized metal may overflow to the outside, resulting in poor bonding.

  From such a viewpoint, it is an object of the present invention to provide a friction stir welding method capable of suppressing damage to a metal member during joining and preventing joining failure due to lack of metal.

In order to solve such a problem, the present invention is a friction stir welding method for joining two metal members using a rotary tool equipped with a stirring pin, and butting the metal members at an angle. A butt step for forming a portion, a tab material arrangement step for arranging tab members on both sides of the butt portion, and overlay welding on inner corners of the metal members formed in the butt step. The overlay welding process of covering the inner corner with a weld metal, and inserting only the rotated stirring pin into the weld metal and the inner corner, and plastically fluidizing the weld metal and the metal member to each other of the butt portion seen including a corner joining step, the inner performing friction stir welding, to prepare a corner joint for frame inner a recess composed of the first inclined surface and a second inclined surface, in the butting process, two of the metal Arranging a member along the recess, The Bed material arranging process, characterized in that arranged the triangular of the tub member along the recess on either side of the butt portion.

Further, the present invention is a friction stir welding method for joining two metal members using a rotary tool equipped with a stirring pin, and abutting step of abutting the metal members at an angle to form a butted portion; and A tab material arranging step of arranging tab materials on both sides of the butting portion, an auxiliary member arranging step of arranging an auxiliary member at an inner corner of the metal members formed in the mating step, and a rotation the inserted stirring pin only to the auxiliary member and the inside corner, seen including and a corner joining step among performing friction stir welding of the auxiliary member and the metallic member and the butted portion by plastically fluidized to each other, the An inner corner joining gantry provided with a concave portion constituted by one inclined surface and a second inclined surface is prepared, and in the abutting step, the two metal members are arranged along the concave portion, and in the tab material arranging step, , Front on both sides of the butt Characterized by each placing triangular of the tub member along the recess.

According to this joining method, since only the stirring pin is brought into contact with the metal member without using a holding block in the rotary tool as in the prior art, damage to the side surfaces of the metal member at the time of joining can be suppressed. In addition, it is possible to compensate for the metal shortage by performing welding in the inner corner between the metal members in advance and applying the weld metal, or by performing the inner corner joining step with the auxiliary member provided. Can be prevented. Moreover, when performing a build-up welding process, the opening of the metal members at the time of performing an inner corner joining process can be prevented. Furthermore, since the metal member and the tab material need only be arranged in the recess by using the inner corner joining base, the abutting step and the tab material arranging step can be easily performed. Moreover, a build-up welding process, an auxiliary member arrangement | positioning process, or an inner corner joining process etc. can be performed stably using the mount for inner corner joining.

  Moreover, it is preferable to include the outer corner joining process which performs friction stir welding with respect to the said butt | matching part from the outer corner side of the said metal members.

  According to this joining method, the joining strength of the butt portion can be increased.

  Moreover, it is preferable to overlap the plasticization area | region formed at the said outer corner joining process, and the plasticization area | region formed at the said inner corner joining process.

  According to such a joining method, since the entire depth direction of the butt portion is frictionally stirred, airtightness and watertightness can be enhanced and joint strength can be enhanced.

  Moreover, it is preferable to include the outer corner joining process of welding with respect to the said butt | matching part from the outer corner side of the said metal members.

  According to this joining method, the joining strength of the butt portion can be increased.

  Moreover, it is preferable to overlap the weld metal formed in the outer corner joining step and the plasticized region formed in the inner corner joining step.

  According to such a joining method, since the entire depth direction of the butt portion is frictionally stirred, airtightness and watertightness can be enhanced and joint strength can be enhanced.

  In the abutting step, the side surface of one metal member and the end surface of the other metal member are abutted, and the angle of the inner corner formed by the side surface of the one metal member and the side surface of the other metal member is In the case of α, in the inner corner joining step, a virtual center axis of rotation of the rotary tool inserted in the line of intersection of the side surfaces passes through the line of intersection and the angle formed with the side surface is α / 2. It is preferable to be located between the reference surface and the side surface of the one metal member.

  According to such a joining method, since the stirring pin can be inserted to a deep position of the abutting portion by tilting the rotary tool toward one of the metal members, it is possible to join to a deep position of the abutting portion.

  According to the friction stir welding method according to the present invention, it is possible to prevent the metal member from being damaged at the time of joining, and to prevent joint failure due to lack of metal.

(A) is the side view which showed the rotation tool for this joining of this embodiment, (b) is sectional drawing which showed the joining form of the rotation tool for this joining. (A) is the side view which showed the large sized rotary tool of this embodiment, (b) is the side view which showed the small sized rotary tool. (A) is the perspective view which showed the butt | matching process which concerns on 1st embodiment of this invention, (b) is the perspective view which showed the outer corner joining process which concerns on 1st embodiment. It is a perspective view which shows the overlay welding process which concerns on 1st embodiment. It is a figure which shows the inner corner joining process which concerns on 1st embodiment, Comprising: (a) is a perspective view, (b) is sectional drawing. (A) is a perspective view which shows the outer corner joining process which concerns on 2nd embodiment of this invention, (b) is sectional drawing which shows the inner corner joining process which concerns on 2nd embodiment. (A) is a perspective view which shows the butt | matching process and tab material arrangement | positioning process which concern on 3rd embodiment of this invention, (b) is a perspective view which shows the outer corner joining process which concerns on 3rd embodiment. It is a figure which shows the auxiliary member arrangement | positioning process which concerns on 3rd embodiment, Comprising: (a) is a perspective view, (b) is II sectional drawing of (a). It is a figure which shows the inner corner joining process which concerns on 3rd embodiment, Comprising: (a) is a perspective view, (b) is sectional drawing. (A) is a perspective view which shows the outer corner joining process which concerns on 4th embodiment of this invention, (b) is sectional drawing which shows the inner corner joining process which concerns on 4th embodiment. (A) is sectional drawing which shows the inner corner joining process which concerns on 5th embodiment of this invention, (b) is sectional drawing which shows the re-outer corner joining process which concerns on 5th embodiment. It is a perspective view which shows the mount for inner corner joining which concerns on the modification of this invention. It is sectional drawing which shows the conventional friction stir welding method.

  Embodiments of the present invention will be described in detail with reference to the drawings. First, the main rotating tool, the large rotating tool, and the small rotating tool used in this embodiment will be described.

  As shown in FIG. 1A, the main joining rotary tool F is composed of a connecting portion F1 and a stirring pin F2. The main rotating tool F for joining is formed of, for example, tool steel. The connection part F1 is a part connected to the rotating shaft D of the friction stirrer shown in FIG. The connecting portion F1 has a cylindrical shape, and is formed with screw holes B and B to which bolts are fastened.

  The stirring pin F2 hangs down from the connecting portion F1 and is coaxial with the connecting portion F1. The stirring pin F2 is tapered as it is separated from the connecting portion F1. A spiral groove F3 is formed on the outer peripheral surface of the stirring pin F2.

  As shown in FIG. 1B, when the friction stir welding is performed using the main rotating tool F, only the rotating stirring pin F2 is inserted into the metal members 1 and 2, and the metal members 1 and 2 are inserted. And the connecting portion F1 are moved while being separated from each other. In other words, the friction stir welding is performed with the base end portion of the stirring pin F2 exposed. A plasticized region W2 is formed on the movement locus of the main rotating tool F for bonding by hardening the friction-stirred metal.

  As shown in FIG. 2A, the large rotary tool G includes a shoulder part G1 and a stirring pin G2. The large rotary tool G is made of, for example, tool steel. The shoulder part G1 is a part connected to the rotating shaft of the friction stirrer and a part for pressing the plastic fluidized metal. The shoulder portion G1 has a cylindrical shape. The lower end surface of the shoulder portion G1 has a concave shape in order to prevent the fluidized metal from flowing out.

  The stirring pin G2 is suspended from the shoulder portion G1, and is coaxial with the shoulder portion G1. The stirring pin G2 is tapered as it is separated from the shoulder portion G1. A spiral groove G3 is formed on the outer peripheral surface of the stirring pin G2. When friction stir welding is performed using the large rotating tool G, the rotated stirring pin G2 and the lower end surface of the shoulder portion G1 are inserted into the metal members 1 and 2 and relatively moved.

  As shown in FIG. 2B, the small rotary tool H includes a shoulder portion H1 and a stirring pin H2. The small rotary tool H is smaller than the main rotating tool F and the large rotary tool G. The small rotary tool H is made of, for example, tool steel. The shoulder portion H1 is a portion that is connected to the rotation shaft of the friction stirrer and is a portion that holds the plastic fluidized metal. The shoulder portion H1 has a cylindrical shape. The lower end surface of the shoulder portion H1 has a concave shape to prevent the fluidized metal from flowing out.

  The stirring pin H2 is suspended from the shoulder portion H1, and is coaxial with the shoulder portion H1. The stirring pin H2 is tapered as it is separated from the shoulder portion H1. A spiral groove H3 is formed on the outer peripheral surface of the stirring pin H2. When friction stir welding is performed using the small rotating tool H, the rotating stirring pin H2 and the lower end surface of the shoulder portion H1 are inserted into the metal members 1 and 2 and relatively moved.

<First embodiment>
Next, the friction stir welding method according to the first embodiment of the present invention will be described. In 1st embodiment, the butt | matching process, the tab material arrangement | positioning process, the outer corner joining process, the build-up welding process, and the inner corner joining process are included.

  As shown in FIG. 3A, the abutting step is a step of abutting the metal members 1 and 2 together. In the abutting step, the side surface 1b of the metal member 1 to be joined and the end surface 2a of the metal member 2 are abutted, and the end surface 1a of the metal member 1 and the side surface 2c of the metal member 2 are flush with each other. That is, in the abutting step, the metal members 1 and 2 are abutted vertically so as to be L-shaped when viewed from the side. A butted portion J1 is formed at a portion where the metal members 1 and 2 are butted. The metal members 1 and 2 may be any metal that can be frictionally stirred, but in the present embodiment, an aluminum alloy is used.

  As shown in FIG. 3B, the tab material arranging step is a step of arranging the tab material 3 on the metal members 1 and 2. In this embodiment, the tab material 3 has a rectangular parallelepiped shape and is formed of the same material as the metal members 1 and 2. In the tab material arranging step, the tab material 3 is arranged on one end side of the butted portion J1 of the metal members 1 and 2, and the side surface of the tab material 3 is brought into contact with the side surface 1d of the metal member 1 and the side surface 2d of the metal member 2. Then, the surface 3a of the tab member 3, the end surface 1a of the metal member 1, and the side surface 2c of the metal member 2 are temporarily joined by welding.

  When the tab material arranging step is completed, the metal members 1 and 2 and the tab material 3 are placed on a frame of a friction stirrer (not shown) and restrained so as not to move using a jig (not shown) such as a clamp.

  The outer corner joining step is a step of friction stir welding the butted portion J1 of the metal members 1 and 2 from the outer corner side of the metal members 1 and 2. In the outer corner joining process, a large rotary tool G is used. As shown in FIG. 3 (b), in the outer corner joining step, a large rotary tool G is inserted into the surface 3a of the tab member 3 and moved relative to the metal members 1 and 2 to enter the abutting portion J1 as it is. Then, the friction stir welding is performed from the outer corner side (surface side constituting the outer corner) of the metal members 1 and 2 to the butted portion J1.

  In the outer corner joining step, the large rotary tool G is relatively moved while the lower end surface of the shoulder portion G1 is pushed into the metal members 1 and 2. A plasticized region W1 is formed on the movement locus of the large-sized rotary tool G. After joining the butt J1, the tab material 3 is cut from the metal members 1 and 2.

  As shown in FIG. 4, the build-up welding process is a process of performing build-up welding on the inner corners of the metal members 1 and 2. In the build-up welding process, build-up welding is performed so as to cover the butt portion J1 at the inner corners of the metal members 1 and 2 (corners formed by the side surface 1b and the side surface 2b). The weld metal M is formed along the butt joint J by the overlay welding process. In this embodiment, the weld metal M is formed of a material equivalent to the metal members 1 and 2.

  As shown in FIG. 5, the inner corner joining step is a step of joining the inner corners of the metal members 1 and 2 using the main joining rotary tool F. In the inner corner joining step according to the present embodiment, first, as shown in FIG. 5A, the backing material T is disposed on the surface constituting the outer corners of the metal members 1 and 2.

  The backing material T is a metal member having an L-shaped cross section, and is brought into contact with the side surface 1 c, the end surface 1 a of the metal member 1, and the side surface 2 c of the metal member 2. Then, the metal members 1 and 2 and the backing material T are placed on a frame of a friction stirrer (not shown) and restrained so as not to move using a jig (not shown) such as a clamp.

  Next, in the inner corner joining process, the rotating tool F for main joining rotated at the inner corners of the metal members 1 and 2 is inserted, and friction stir welding is performed on the butt portion J1. In the inner corner joining step, as shown in FIGS. 5A and 5B, the connecting portion F1 of the main joining rotary tool F and the metal members 1 and 2 are separated from each other, and only the stirring pin F2 is welded metal. M is inserted into the butt J1. A plasticized region W2 is formed on the movement trajectory of the main rotating tool for welding F.

  In the inner corner joining step, as shown in FIG. 5B, the friction stir welding is performed by tilting the rotation center axis Fc of the main welding rotary tool F. That is, in the inner corner joining step, the angle formed between the side surface 1b and the side surface 2b by the rotation center axis Fc of the main welding rotary tool F inserted at the intersection line C1 between the side surface 1b and the side surface 2b passes through the intersection line C1. It is set so as to be positioned between the virtual reference plane C that is α / 2 (α = 90 ° in the present embodiment) and the side surface 1b of the metal member 1. In the inner corner joining process, the plasticizing region W2 formed in the inner corner joining step and the plasticizing region W1 formed in the outer corner joining step are set so as to overlap on the butted portion J1. The position of the rotation center axis Fc does not include a position overlapping the side surface 1b and the virtual reference plane C.

  According to the friction stir welding according to the present embodiment described above, in the inner corner joining step for joining the inner corners of the metal members 1 and 2, only the stirring pin F <b> 2 is used as the metal member without using a pressing block as in the prior art. Since they are brought into contact with 1 and 2, damage to the side surface 1b of the metal member 1 and the side surface 2b of the metal member 2 during joining can be suppressed. Moreover, since the holding block is not used as in the prior art, the joint portion can be visually recognized. Thereby, since a joining condition etc. can be grasped | ascertained, workability | operativity can be improved.

  Moreover, in this embodiment, after performing build-up welding, by performing an inner corner joining process via the weld metal M formed by build-up welding, in addition to the metal members 1 and 2, the weld metal M is also plastically flowed. Therefore, the shortage of metal can be compensated. Thereby, the joining failure by metal shortage can be prevented. Further, by performing overlay welding before the inner corner joining step, it is possible to prevent the opening of the metal members 1 and 2 when the inner corner joining step is performed.

  Moreover, in this embodiment, since friction stir welding is performed with respect to the butt | matching part J1 also from the outer corner of the metal members 1 and 2, joining strength can be raised. In this embodiment, since the plasticized region W1 formed in the outer corner joining step and the plasticized region W2 formed in the inner corner joining step overlap on the butt portion J1, the depth of the butt portion J1 is increased. The entire length is frictionally stirred. Thereby, the air tightness and water tightness of the joint portion are improved, and the joint strength can be further increased.

  Moreover, in this embodiment, since the outer corner side of the metal members 1 and 2 is joined in the outer corner joining process prior to the overlay welding process, the eyes of the metal members 1 and 2 when the overlay welding process is performed. Opening can be prevented.

  Further, in the inner corner joining process, for example, the stirring pin F2 is inserted along the virtual reference plane C shown in FIG. 5B by inclining the main joining rotary tool F to the one metal member 1 side. In other words, compared to the case where the angle between the side surfaces 1b and 2b and the rotation center axis Fc is 45 ° with respect to the metal members 1 and 2 that are vertical, the agitation is performed to a deeper position of the butted portion J1. Pin F2 can be inserted. Thereby, it can join to the deep position of the butt | matching part J1.

  Although the first embodiment of the present invention has been described above, design changes can be made as appropriate. For example, in this embodiment, the inner corner joining process is performed after the outer corner joining process is performed, but the outer corner joining process may be performed after the inner corner joining process is performed.

  In addition, before performing the outer corner joining step, temporary joining may be performed by friction stir from the outer corners of the metal members 1 and 2 to the butted portion J1 using the small rotary tool H. Or before performing an outer corner joining process, you may perform temporary joining by welding with respect to the butt | matching part J1 from the outer corner of the metal members 1 and 2. FIG. Thereby, when performing an outer corner joining process, the opening of the metal members 1 and 2 can be prevented.

  Moreover, although the large corner rotary tool G was used in this embodiment, you may perform an outer corner joining process using the rotary tool F for main joining. Thereby, friction stirring can be performed to the deep position of the butt | matching part J1, in the state where a big load is not applied to a friction stirring apparatus.

<Second embodiment>
Next, the friction stir welding method according to the second embodiment of the present invention will be described. In 2nd embodiment, a butt | matching process, an outer corner joining process, an overlay welding process, and an inner corner joining process are included. The second embodiment is different from the first embodiment in that the outer corner joining step is performed by welding.

  Since the matching process is substantially the same as that of the first embodiment, description thereof is omitted. As shown in FIG. 6A, the outer corner joining step is a step of welding the butt portion J1 from the outer corner side of the metal members 1 and 2. A weld metal M1 is formed in the butt joint J1 by the outer corner joining process.

  As shown in FIG. 6B, the build-up welding process and the inner corner joining process are substantially the same as those in the first embodiment, and thus the description thereof is omitted. In the friction stir welding method according to the second embodiment, substantially the same effect as that of the first embodiment can be obtained except that the gap S is formed in the butt portion J1. Moreover, since the outer corners of the metal members 1 and 2 are joined by welding before the build-up welding process, the openings of the metal members 1 and 2 during the build-up welding process can be prevented.

  In the present embodiment, the outer corner joining process is performed by welding. However, the outer corner joining process is performed by friction stir from the outer corner side of the metal members 1 and 2 to the butt portion J1 using the small rotary tool H. May be.

  As shown in FIG. 6B, in the second embodiment, a gap S is generated between the weld metal M1 and the plasticized region W2. It is preferable to overlap a plasticizing region (not shown) formed in the movement locus of the weld metal M1 or the small rotary tool H formed in the outer corner and a plasticizing region W2 formed in the inner corner joining step. Thereby, since the clearance gap S of the butt | matching part J1 can be filled, while being able to improve watertightness and airtightness, joint strength can be raised.

<Third embodiment>
Next, the friction stir welding method according to the third embodiment of the present invention will be described. In 3rd embodiment, the butt | matching process, the tab material arrangement | positioning process, the outer corner joining process, the auxiliary member arrangement | positioning process, and the inner corner joining process are included.

  As shown to (a) of FIG. 7, since the colliding process is substantially equivalent to 1st embodiment, description is abbreviate | omitted. The tab material arranging step is a step of arranging the tab material 4 on the metal members 1 and 2. In this embodiment, the tab material 4 has a triangular prism shape and is formed of the same material as the metal members 1 and 2. The cross section of the tab material 4 is a right-angled isosceles triangle.

  In the tab material arranging step, the tab material 4 is arranged on one end side of the abutting portion J1 of the metal members 1 and 2, and the side surface 4c of the tab material 4 (the surface exhibiting a triangle) is arranged between the side surface 1d of the metal member 1 and the metal member 2. It abuts on the side surface 2d. Then, the surface 4a of the tab member 4, the end surface 1a of the metal member 1 and the side surface 2c of the metal member 2 are temporarily joined by welding while being flush with each other.

  When the tab material arranging step is completed, the metal members 1 and 2 and the tab material 4 are placed on a frame of a friction stirrer (not shown) and restrained so as not to move using a jig (not shown) such as a clamp.

  As shown in FIG. 7 (b), the outer corner joining step is a step of friction stir welding the butted portion J1 of the metal members 1 and 2 from the outer corner side of the metal members 1 and 2. Since the outer corner joining process is substantially the same as that of the first embodiment except that the tab material 4 is used, detailed description thereof is omitted.

  As shown in FIG. 8, the auxiliary member arranging step is a step of arranging the auxiliary member 10 at the inner corners of the metal members 1 and 2. The auxiliary member 10 has a triangular prism shape and is formed of the same material as the metal members 1 and 2. The cross section of the auxiliary member 10 is a right-angled isosceles triangle. The auxiliary member 10 is formed with a length that covers the extending direction of the butted portion J1.

  In the auxiliary member arranging step, the side surface 10 a of the auxiliary member 10 is brought into contact with the side surface 1 b of the metal member 1, and the side surface 10 b is brought into contact with the side surface 2 b of the metal member 2. Moreover, it arrange | positions so that the inclined surface 10c of the auxiliary member 10 and the inclined surface 4b of the tab material 4 may become flush | level. What is necessary is just to set suitably the cross-sectional shape of the auxiliary member 10 so that the side surfaces 1b and 2b and the side surfaces 10a and 10b may be in surface contact according to the butting angle (inner angle) of the metal members 1 and 2, respectively. Further, the size of the auxiliary member 10 may be set as appropriate so that the metal does not become deficient in the inner corner joining step described later and the metal overflowing by friction stirring is minimized.

  As shown in FIG. 9, the inner corner joining step is a step of joining the inner corners of the metal members 1 and 2 using the main joining rotary tool F. In the inner corner joining step according to the present embodiment, first, as shown in FIG. 9A, the backing material T is disposed on the surface constituting the outer corners of the metal members 1 and 2.

  The backing material T is a metal member having an L-shaped cross section, and is brought into contact with the side surface 1 c, the end surface 1 a of the metal member 1, and the side surface 2 c of the metal member 2. Then, the metal members 1 and 2 and the backing material T are placed on a frame of a friction stirrer (not shown) and restrained so as not to move using a jig (not shown) such as a clamp.

  Next, in the inner corner joining step, the rotated main joining rotary tool F is inserted into the inclined surface 4 b of the tab member 4, and the main joining rotational tool F is relatively moved toward the metal members 1 and 2. And if it reaches the auxiliary member 10, friction stir welding will be performed with respect to the auxiliary member 10 and the butt | matching part J1 as it is. In the inner corner joining step, as shown in FIGS. 9A and 9B, the connecting portion F1 of the main joining rotary tool F and the metal members 1 and 2 are separated from each other, and only the stirring pin F2 is used as an auxiliary member. 10 and inserted into the butt J1. A plasticized region W2 is formed on the movement trajectory of the main rotating tool for welding F. Since the insertion angle of the main rotating tool F for welding is the same as that of the first embodiment, description thereof is omitted.

  According to the friction stir welding according to the present embodiment described above, in the inner corner joining step of joining the inner corners of the metal members 1 and 2, only the stirring pin F2 is brought into contact with the metal members 1 and 2 when joining. Damage to the side surface 1b of the metal member 1 and the side surface 2b of the metal member 2 can be suppressed.

  Further, in the present embodiment, the auxiliary member 10 is disposed at the inner corners of the metal members 1 and 2, and the auxiliary member 10 is added to the metal members 1 and 2 by performing friction stirring on the auxiliary member 10 and the metal members 1 and 2. Can be compensated for metal shortage. Thereby, the joining failure by a metal member can be prevented.

  In this embodiment, since friction stir welding is performed with respect to the butt | matching part J1 also from the outer corner side of the metal members 1 and 2, joining strength can be raised. In the present embodiment, since the plasticized region W1 formed in the outer corner joining step and the plasticized region W2 formed in the inner corner joining step are overlapped on the butted portion J1, The entire depth direction is frictionally stirred. Thereby, the air tightness and water tightness of the joint portion are improved, and the joint strength can be further increased.

  Further, since the outer corner joining step is performed prior to the inner corner joining step, the opening of the metal members 1 and 2 in the auxiliary member arranging step and the inner corner joining step can be prevented.

  Further, in the inner corner joining process, for example, the stirring pin F2 is inserted along the virtual reference plane C shown in FIG. 9B by inclining the main joining rotary tool F toward the one metal member 1 side. In other words, compared to the case where the angle between the side surfaces 1b and 2b and the rotation center axis Fc is 45 ° with respect to the metal members 1 and 2 that are vertical, the agitation is performed to a deeper position of the butted portion J1. Pin F2 can be inserted. Thereby, it can join to the deep position of the butt | matching part J1.

  Moreover, since the inclined surface 4b of the tab member 4 and the inclined surface 10c of the auxiliary member 10 are flush with each other, the inner corner joining process can be easily performed. Further, by cutting off the tab material 4 after the inner corner joining step, the side surface 1d of the metal member 1 and the side surface 2d of the metal member 2 can be finished finely while reliably joining the end portions of the butted portion J1.

  Although the third embodiment has been described above, design changes can be made as appropriate. For example, in this embodiment, the inner corner joining process is performed after the outer corner joining process is performed, but the outer corner joining process may be performed after the inner corner joining process is performed.

  In addition, before performing the outer corner joining step, temporary joining may be performed by friction stir from the outer corners of the metal members 1 and 2 to the butted portion J1 using the small rotary tool H. Or before performing an outer corner joining process, you may perform temporary joining by welding with respect to the butt | matching part J1 from the outer corner of the metal members 1 and 2. FIG. Thereby, when performing an outer corner joining process, the opening of the metal members 1 and 2 can be prevented.

  Moreover, although the large corner rotary tool G was used in this embodiment, you may perform an outer corner joining process using the rotary tool F for main joining. Thereby, friction stirring can be performed to the deep position of the butt | matching part J1, in the state where a big load is not applied to a friction stirring apparatus.

<Fourth embodiment>
Next, a friction stir welding method according to a fourth embodiment of the present invention will be described. In 4th embodiment, a butt | matching process, a tab material arrangement | positioning process, an outer corner joining process, an auxiliary member arrangement | positioning process, and an inner corner joining process are included. The outer corner joining process of the fourth embodiment is different from the third embodiment in that a small rotary tool H is used.

  Since the abutting step and the tab material arranging step are substantially the same as those in the third embodiment, description thereof is omitted. The outer corner joining step is a step of performing friction stir welding from the outer corner side of the metal members 1 and 2 to the butted portion J1 as shown in FIG.

  In the outer corner joining process, the small rotary tool H is inserted into the surface 4a of the tab member 4 and relatively moved toward the metal members 1 and 2, while the small rotary tool H is relatively moved along the abutting portion J1. A plasticized region W3 is formed on the movement locus of the small rotary tool H.

  As shown in FIG. 10B, the auxiliary member arranging step and the inner corner joining step are substantially the same as those in the third embodiment, and thus the description thereof is omitted. In the friction stir welding method according to the fourth embodiment, substantially the same effect as that of the third embodiment can be achieved except that the gap S is formed in the butt portion J1. Moreover, since the outer corners of the metal members 1 and 2 are joined by friction stirring before the auxiliary member arranging step, the opening of the metal members 1 and 2 can be prevented during the auxiliary member arranging step.

  In this embodiment, the outer corner joining process is performed by friction stir welding using the small rotary tool H. However, the outer corner joining process is performed by welding from the outer corner side of the metal members 1 and 2 to the butt portion J1. May be.

  In addition, as shown in FIG. 10B, in the fourth embodiment, a gap S is generated between the plasticized region W2 and the plasticized region W3. It is preferable to overlap the plasticized region W3 or weld metal (not shown) formed on the outer corner side and the plasticized region W2 formed in the inner corner joining step. Thereby, since the clearance gap S of the butt | matching part J1 can be filled, while being able to improve watertightness and airtightness, joint strength can be raised.

<Fifth embodiment>
Next, friction stir welding according to the fifth embodiment of the present invention will be described. The fifth embodiment is different from the above-described embodiment in that a re-outer corner joining process is performed. In the fifth embodiment, a description will be given centering on parts different from the above-described embodiment.

  FIG. 11A is a cross-sectional view showing an inner corner joining step according to the fifth embodiment. In the fifth embodiment, the outer corner joining step is performed prior to the inner corner joining step, and the plasticized region W1 is formed on the outer corner side of the butted portion J1. As shown in FIG. 11A, for example, when joining metal members 1 and 2 having a large plate thickness, the entire butt joint J1 cannot be friction stir welded even if the outer corner joining step and the inner corner joining step are performed. There is a case.

  That is, the plasticized region W1 formed in the outer corner joining process and the plasticized region W2 formed in the inner corner joining process cannot be overlapped on the butted portion J1, and a gap S may be generated. is there. In the case of FIG. 6 and FIG. 10 as well, a gap S is generated in the butt portion J1.

  When the gap S is generated on the abutting portion J1 in this way, as shown in FIG. 11 (b), the main rotating tool F is joined to the abutting portion J1 from the outer corner side of the metal members 1 and 2. It is preferable to perform a re-outer corner joining process. In the outer outer corner joining process, friction stirring is performed in a state where only the stirring pin F2 of the rotating tool F for main joining is in contact with the metal members 1 and 2. A plasticized region W4 is formed on the movement trajectory of the main welding rotary tool F in the re-outer corner welding process.

  In the re-outer corner joining process, since the main joining rotary tool F is used, it is possible to friction stir the deep position of the butt portion J1 without applying a large load to the friction stirrer. Thereby, since the gap S generated in the butt portion J1 is frictionally stirred, the water tightness and the air tightness of the butt portion J1 can be improved, and the bonding strength can be further improved.

<Modification>
Next, a modification of the friction stir welding of the present invention will be described. In the above-described embodiment, the backing material T is used on the back side of the metal members 1 and 2 when performing the inner corner joining step, but an inner corner joining base U may be used as shown in FIG.

  The inner corner joining base U includes a recess U1 on the surface of a metal member having a rectangular parallelepiped shape. The recess U1 is composed of a first inclined surface U1a and a second inclined surface U1b. The internal angle between the first inclined surface U1a and the second inclined surface U1b is, for example, 90 degrees.

  In the butting process in the modification, the metal members 1 and 2 are disposed along the recess U1. Further, in the tab material arranging step, the tab materials 4 and 4 are arranged on both sides of the butted portion J1 of the metal members 1 and 2. The tab member 4 is arranged so that the inclined surface 4b faces upward. When the tab members 4 and 4 are arranged, the metal members 1 and 2 and the tab members 4 and 4 are clamped and fixed so as not to move by the fixing jigs U2 and U2 (only one of them is drawn).

  By using the inner corner joining base U of the modified example, the metal members 1 and 2 and the tab material 4 need only be arranged in the recess U1, so that the abutting step and the tab material arranging step can be easily performed. Moreover, the build-up welding process, the auxiliary member arrangement process, the inner corner joining process, and the like can be stably performed using the inner corner joining base U.

  Moreover, in this embodiment, although the internal angle of the metal members 1 and 2 was set to 90 degrees, you may set to another angle. In such a case, the metal members 1 and 2 can be faced | matched by various angles by changing suitably the internal angle of 1st inclined surface U1a and 2nd inclined surface U1b.

DESCRIPTION OF SYMBOLS 1 Metal member 1a End surface 1b Side surface 1c Side surface 1d Side surface 2 Metal member 2a End surface 2b Side surface 2c Side surface 2d Side surface 3 Tab material 4 Tab material C Virtual reference plane C1 Intersection line F Main rotation tool F1 Connecting part F2 Stirring pin G Large rotation Tool H Small rotating tool J1 Butting part W1-W4 Plasticization region

Claims (7)

A friction stir welding method for joining two metal members using a rotary tool equipped with a stirring pin,
A butting step of butting the metal members at an angle to form a butting portion;
A tab material arranging step of arranging tab materials on both sides of the abutting portion;
Overlay welding step of performing overlay welding on the inner corners of the metal members formed in the abutting step and covering the inner corner with weld metal,
Only the stirring pin rotated and inserted into the weld metal and the inner corner, seen including and a corner joining step among performing friction stir welding of the weld metal and the metal member and the butted portion by plastically fluidized to each other ,
Prepare an inner corner joining gantry comprising a recess composed of a first inclined surface and a second inclined surface,
In the abutting step, the two metal members are arranged along the recess,
In the tab material arranging step, the tabular triangular tab material is arranged along the concave portion on both sides of the butting portion, respectively . A friction stir welding method for joining two metal members using a rotary tool equipped with a stirring pin,
A butting step of butting the metal members at an angle to form a butting portion;
A tab material arranging step of arranging tab materials on both sides of the abutting portion;
An auxiliary member arranging step of arranging an auxiliary member at an inner corner between the metal members formed in the abutting step;
Only the stirring pin rotated and inserted into the auxiliary member and the inside corner, seen including and a corner joining step among performing friction stir welding of the auxiliary member and the metallic member and the butted portion by plastically fluidized to each other ,
Prepare an inner corner joining gantry comprising a recess composed of a first inclined surface and a second inclined surface,
In the abutting step, the two metal members are arranged along the recess,
In the tab material arranging step, the tabular triangular tab material is arranged along the concave portion on both sides of the butting portion, respectively .   3. The friction stir welding method according to claim 1, further comprising an outer corner joining step in which friction stir welding is performed from the outer corner side of the metal members to the butting portion.   4. The friction stir welding method according to claim 3, wherein the plasticized region formed in the outer corner joining step and the plasticized region formed in the inner corner joining step are overlapped.   3. The friction stir welding method according to claim 1, further comprising an outer corner joining step of welding the butt portion from the outer corner side of the metal members.   The friction stir welding method according to claim 5, wherein the weld metal formed in the outer corner joining step and the plasticized region formed in the inner corner joining step are overlapped. In the abutting step, the side surface of one metal member and the end surface of the other metal member are abutted, and the angle of the inner corner formed by the side surface of the one metal member and the side surface of the other metal member is α. If there is
In the inner corner joining step, the rotation center axis of the rotary tool inserted at the intersection line of the side surfaces passes through the intersection line and the virtual reference plane having an angle of α / 2 with the one side and the one side The friction stir welding method according to any one of claims 1 to 6, wherein the friction stir welding method is located between the metal member and a side surface of the metal member.

Images