JP2009136881A - Joining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining method including a step of performing the friction stir welding to a butted part of a pair of metallic members from a surface side and a back side, and capable of enhancing the airtightness and the watertightness between both side surfaces of the metallic members. <P>SOLUTION: The joining method includes a butting step of butting a first metallic member 1a to a second metallic member 1b, a welding step of performing the welding of a butted part J1 of the joined metallic member 1 from a surface A, a back side B, a first side surface C and a second side surface D, a first permanent joining step of performing the friction stir welding of the butted part J1 from the surface A of the joined metallic member 1, and a second permanent joining step of performing the friction stir welding of the joined part J1 from the back side of the joined metallic member 1. In the first permanent joining step, the weld metal formed in the welding step and the joined metallic member 1 are subjected to the friction stir welding. In the second permanent joining step, the weld metal formed in the welding step and the joined metallic member 1 are subjected to the friction stir welding. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for joining metal members using friction stirring.

  Friction stir welding (FSW = Friction Stir Welding) is known as a method for joining metal members. Friction stir welding is a process of rotating a rotating tool along the abutting portion between metal members, and plastically flowing the metal at the abutting portion by frictional heat between the rotating tool and the metal member, so that the metal members are solid-phased. It is what is joined. In general, the rotating tool is formed by projecting a stirring pin (probe) on the lower end surface of a cylindrical shoulder.

Here, FIGS. 22 and 23 are perspective views showing a conventional joining method in which friction stir welding is performed on a pair of metal members. As shown in FIG. 22, when the thickness of the metal members 101, 101 to be joined is larger than the length of the stirring pin of the rotating tool (not shown), after performing the friction stir welding from the surface 102 side of the metal member 101. In some cases, friction stir welding is also performed from the back surface 103 side.
That is, in the conventional joining method, the friction stir welding is performed from both sides of the front surface 102 and the back surface 103 along the abutting portion 104 (two-dot chain line) of the metal members 101, 101, and the plasticized region 105 formed by the friction stir welding is formed. , 106 are joined so that the central portions in the thickness direction are in contact with each other. Thereby, in the butt | matching part 104, it can join without a clearance gap.

Japanese Patent Laying-Open No. 2005-131666 (see FIG. 7)

  However, as shown in FIG. 23, when the thickness of the metal members 111 and 111 to be joined is large, even if friction stir welding is performed from the front surface 102 and the back surface 103, the center portion of the abutting portion 104 (two-dot chain line) is not yet present. Joining may occur. That is, when the thickness of the metal member 111 is very large with respect to the length of the stirring pin of the rotating tool (not shown), even if friction stirring is performed from the front surface 102 and the back surface 103 of the metal member 111, the plasticized region 105 is obtained. , 106 cannot be brought into contact with the central portion in the thickness direction, and a gap (unjoined portion) 119 is generated in the central portion of the abutting portion 114. As described above, when the gap 119 continuous from the one side surface 107 to the other side surface 108 is generated, there is a problem that watertightness and airtightness between the side surface 107 and the side surface 108 are deteriorated.

  Here, if the length of the stirring pin of the rotary tool is increased according to the thickness of the metal member 111, it is possible to join the metal members 111 without gaps by performing friction stir welding from the front surface 102 and the back surface 103. is there. However, since the rotating tool moves while the stirring pin is buried in the metal member 111 and rotates at a high speed, if the length of the stirring pin is increased, the load acting on the driving means of the friction stirrer and the stirring pin increases. However, there is a problem that the life of the apparatus is shortened.

  From such a viewpoint, the present invention is a joining method including a step of performing frictional stirring from the front surface side and the back surface side of the metal member with respect to the abutting portion between the pair of metal members, and both side surfaces of the pair of metal members It is an object of the present invention to provide a joining method capable of improving the air tightness and water tightness between them.

  The joining method according to the present invention that solves such a problem includes a butting step of butting the end surface of the first metal member and the end surface of the second metal member, and a butting portion of the metal member to be joined formed in the butting step. Welding first step for performing friction stir from the surface of the metal member to be joined to the butted portion after the welding and joining step, welding from the front surface, back surface and side surface, After the first main joining step, the second main joining step in which friction agitation is performed from the back surface of the metal member to be joined to the abutting portion, and formed in the welding joining step in the first main joining step. Friction stir of the weld metal formed and the metal member to be joined, and friction stir of the weld metal formed in the weld joint step and the metal member to be joined in the second main joining step. To do.

  According to such a joining method, welding is performed from the front, back and side surfaces of the butt portion of the metal member to be joined to seal the butt portion, and the weld metal and the metal to be joined in the first main joining step and the second main joining step. By friction-stirring the interface with the member, the watertightness and airtightness of the metal member to be joined can be further increased.

Moreover, it is preferable that the welding joining process which concerns on this invention includes the welding metal filling process filled with the said weld metal to the ditch | groove formed along the said abutting part in the side surface of the said to-be-joined metal member.
Moreover, the welding joining process which concerns on this invention includes the welding metal filling process which fills the said grooved metal in the groove formed along the said abutting part in at least one of the surface of the said to-be-joined metal member, and a back surface. Is preferred.

  According to this joining method, the workability of welding can be improved by providing the concave groove and filling the weld metal.

  Further, in the present invention, the depth of the plasticized region formed in the first main joining step and the depth of the plasticized region formed in the second main joining step are formed on the front surface and the back surface of the metal member to be joined. It is preferable that the depth is larger than the depth of the concave groove.

  According to such a joining method, since the interface where the concave groove and the weld metal are in contact with each other is frictionally stirred, airtightness and watertightness can be further improved.

  In addition, the present invention provides a butting process of abutting the side surface of the first metal member and the end surface of the second metal member, and the front surface, the back surface, and the side surface with respect to the butting portion of the metal member to be bonded formed in the butting process. A welding joint process for performing welding, a first main joining process for performing friction stir from the surface of the metal member to be joined to the butted portion after the welding joining process, and after the first main joining process, A second main joining step in which friction agitation is performed from the back surface of the metal member to be joined to the abutting portion, and in the first main joining step, the weld metal formed in the weld joining step and the metal to be joined The member is frictionally stirred, and in the second main joining step, the weld metal formed in the welding joining step and the metal member to be joined are frictionally stirred.

  According to such a joining method, welding is performed from the front, back and side surfaces of the butt portion of the metal member to be joined to seal the butt portion, and the weld metal and the metal to be joined in the first main joining step and the second main joining step. By friction-stirring the interface with the member, the watertightness and airtightness of the metal member to be joined can be further increased.

Moreover, it is preferable that the welding joining process which concerns on this invention includes the welding metal filling process which fills the said welding metal to the ditch | groove formed along the said abutting part in the side surface side of the end surface of said 2nd metal member. .
Moreover, the welding joining process which concerns on this invention includes the welding metal filling process which fills the said grooved metal in the groove formed along the said abutting part in at least one of the surface of the said to-be-joined metal member, and a back surface. Is preferred.

  According to this joining method, the workability of welding can be improved by providing the concave groove and filling the weld metal.

  In addition, the depth of the plasticized region formed in the first main joining step and the plasticized region formed in the second main joining step according to the present invention are formed on the front surface and the back surface of the metal member to be joined. It is preferable that the depth is larger than the depth of the concave groove.

  According to such a joining method, the interface where the bottom surface of the groove and the weld metal are in contact with each other is friction-stirred, so that airtightness and watertightness can be further improved.

  Moreover, it is preferable that this invention includes the excision process of excising the part protruded from the surface of the to-be-joined metal member, the back surface, and the side surface among the said weld metals after the said welding joining process. According to this joining method, each surface of the metal member to be joined can be formed smoothly.

  In the present invention, it is preferable that a pilot hole is formed in advance at a planned insertion position of the rotary tool used in the friction stirring. According to such a joining method, it is possible to reduce the insertion resistance that occurs when the rotary tool is pushed into the planned insertion position, and it is possible to perform the friction stir welding accurately and quickly because the rotary tool is guided to the pilot hole. it can.

  In the joining method according to the present invention, the abutting portions between a pair of metal members are subjected to friction stirring from the front side and the back side of the metal members, and the air tightness and water tightness between both side surfaces of the pair of metal members can be improved. it can.

[First embodiment]
As shown in FIG. 1, the joining method according to the present invention includes a front surface A, a back surface B, and a first surface with respect to an abutting portion J1 of a to-be-joined metal member 1 formed by abutting the first metal member 1a and the second metal member 1b. While welding is performed from the side surface C and the second side surface D, friction stirring is performed from the front surface A and the back surface B.
First, the bonded metal member 1 of the bonding method according to the present embodiment will be described in detail. The vertical and horizontal directions in the present embodiment follow the arrows in FIG.

  As shown in FIGS. 2A and 2B, the bonded metal member 1 includes a first metal member 1a and a second metal member 1b that are rectangular in cross section in the present embodiment, and each end face 11a, The abutting portion J1 is formed by abutting 11b. In the present embodiment, the first metal member 1a and the second metal member 1b are metal materials having the same composition, for example, friction such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium alloy, magnesium, and magnesium alloy. It consists of a stirrable metal material. Although there is no restriction | limiting in particular in the shape and dimension of the 1st metal member 1a and the 2nd metal member 1b, It is desirable to make the thickness dimension in the abutting part J1 the same at least.

  On the end surface 11a side of the surface 12a of the first metal member 1a, a concave groove K1a is formed which continues from one side surface 14a to the other side surface 15a. A concave groove K2a is formed on the end surface 11a side of the back surface 13a of the first metal member 1a so as to continue from one side surface 14a to the other side surface 15a. The concave groove K1a and the concave groove K2a have a rectangular shape in cross section, and are formed with a predetermined depth (vertical height in FIG. 1) and width (longitudinal length in FIG. 1).

  On the other hand, a concave groove K1b that continues from one side surface 14b to the other side surface 15b is formed on the end surface 11b side of the surface 12b of the second metal member 1b. Further, on the end surface 11b side of the back surface 13b of the second metal member 1b, a concave groove K2b that continues from one side surface 14b to the other side surface 15b is formed. The concave groove K2a and the concave groove K2b have a rectangular shape in cross section and are formed with a predetermined depth and width.

  As shown in FIG. 2B, the concave groove K1 is formed by abutting the concave groove K1a and the concave groove K1b. Also, the concave groove K2 (not shown) is formed by abutting the concave groove K2a and the concave groove K2b. The concave groove K1 and the concave groove K2 are portions that are filled with weld metal in a weld metal filling step described later.

  Next, the joining method according to this embodiment will be described. The joining method according to the present embodiment includes (1) a butt process, (2) a welding joint process, (3) a first main joining process, and (4) a second main joining process.

(1) Butting process In the butting process, the end surface 11a of the first metal member 1a and the end surface 11b of the second metal member 1b are butted together to form the metal member 1 to be joined. That is, in the abutting step, as shown in FIGS. 2A and 2B, the surface 12a of the first metal member 1a and the surface 12b of the second metal member 1b are flush with each other, and the first metal member The back surface 13a of 1a and the back surface 13b of the second metal member 1b are flush with each other. Further, the one side surface 14a of the first metal member 1a and the one side surface 14b of the second metal member 1b are flush with each other, and the other side surface 15a of the first metal member 1a and the other side surface of the second metal member 1b. 15b.

An abutting portion J1 is formed at the abutting portion of the first metal member 1a and the second metal member 1b. Moreover, the concave groove K1 is formed in the surface side of the to-be-joined metal member 1, and the concave groove K2 is formed in a back surface side by abutting the opposing concave groove of the 1st metal member 1a and the 2nd metal member 1b.
Here, the surface of the metal member 1 to be bonded is the front surface A, the back surface is the back surface B, one side surface is the first side surface C, and the other side surface is the second side surface D.

(2) Welding and joining process In the welding and joining process, welding is performed along the abutting portion J1 exposed on the front surface A, the back surface B, the first side surface C, and the second side surface D of the metal member 1 to be joined. The welding joint process in this embodiment includes a first weld metal filling process for filling the groove K1 with the weld metal T1, and a first excision for cutting out a portion of the weld metal T1 protruding from the surface A of the metal member 1 to be joined. A step, a second weld metal filling step of filling the groove K2 with the weld metal T2, a second excision step of cutting a portion of the weld metal T2 protruding from the back surface B of the metal member 1 to be joined, and a first side surface C, a third groove forming step for forming the groove K3 along the abutting portion J1, a fourth groove forming step for forming the groove K4 along the abutting portion J1 on the second side surface D, A third weld metal filling step of filling the groove K3 with the weld metal T3, a third excision step of cutting a portion of the weld metal T3 protruding from the first side C of the metal member 1 to be joined, and welding to the groove K4 A fourth weld metal filling step for filling metal T4; Including a fourth excision step of excising a portion protruding from the second side surface D of the joining metallic member 1 of the contact metal T4.

  In the first weld metal filling step, as shown in FIG. 3A, build-up welding is performed on the concave groove K <b> 1 formed on the surface A of the bonded metal member 1. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K1 with the weld metal T1. The overlay welding is preferably performed so that the weld metal T1 protrudes upward from the surface A. As shown in FIG. 2B, a portion of the weld metal T1 that protrudes upward from the surface A is defined as a built-up portion T1 '.

  The first excision step is a step of excising the built-up portion T1 'protruding from the surface A using a known cutting tool. According to the first excision step, the surface A can be formed smoothly, and the large rotary tool G can be smoothly moved during the first main joining step described later. In addition, when the weld metal T1 protrudes from the first side surface C and the second side surface D, it is preferable to cut off the protruding portion.

  In the second weld metal filling step, although not specifically shown, overlay welding is performed on the concave groove K2 (see FIG. 4) formed on the back surface B of the metal member 1 to be joined. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K2 with the weld metal T2 (see FIG. 4). The overlay welding is preferably performed such that the weld metal T2 protrudes from the back surface B. The part which protrudes from the back surface B among welding metal T2 is made into a built-up part.

  The second excision step is a step of excising the built-up portion protruding from the back surface B using a known cutting tool. According to the second excision step, the back surface B can be formed smoothly, and the large rotary tool G can be smoothly moved during the second main joining step described later. In addition, when the weld metal T2 protrudes from the first side surface C and the second side surface D, it is preferable to cut off the protruding portion.

  In the third groove forming step, as shown in FIG. 5, the groove K3 is formed on the first side surface C along the abutting portion J1 using a known end mill or the like. The concave groove K3 is rectangular in a sectional view and is continuously formed from the front surface A to the back surface B. The concave groove K3 is formed with a depth and width substantially equal to the concave groove K1. Moreover, the unwelded area | region is exposed in the bottom face of the ditch | groove K3 among the butt | matching parts J1.

  In the fourth concave groove forming step, as shown in FIG. 5, the concave groove K4 is formed on the second side surface D along the abutting portion J1 using a known end mill or the like. The concave groove K4 is rectangular in a sectional view and is continuously formed from the front surface A to the back surface B. The concave groove K4 is formed with a depth and width substantially equal to the concave groove K1. Moreover, the unwelded area | region is exposed to the bottom face of the ditch | groove K4 among the butt | matching parts J1.

  In the third weld metal filling step, as shown in FIG. 6A, overlay welding is performed on the groove K3 formed in the first side surface C of the metal member 1 to be joined. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K3 with the weld metal T3. The overlay welding is preferably performed so that the weld metal T3 protrudes from the first side face C. As shown in FIG. 6B, a portion of the weld metal T3 that protrudes from the first side surface C is defined as a build-up portion T3 '.

  The third excision step is a step of excising the built-up portion T3 'protruding from the first side surface C using a known cutting tool. According to the third cutting step, the first side surface C can be formed smoothly. Thereby, in the tab material arrangement | positioning process mentioned later, a tab material can be suitably made to contact | abut to the 1st side surface C of the to-be-joined metal member 1. FIG. In addition, when the weld metal T3 protrudes outside from the front surface A and the back surface B, it is preferable to excise the protruded part.

  In the fourth weld metal filling step, although not specifically shown, overlay welding is performed on the concave groove K4 (see FIG. 5) formed on the second side face D of the metal member 1 to be joined. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K4 with the weld metal T4. The overlay welding is preferably performed so that the weld metal T4 (see FIG. 7) protrudes from the second side face D. The part which protrudes rather than the 2nd side D among welding metal T4 is made into a built-up part.

  The fourth excision step is a step of excising the built-up portion protruding from the second side surface D using a known cutting tool. According to the fourth excision step, the second side face D can be formed smoothly. Thereby, in the tab material arrangement | positioning process mentioned later, a tab material can be suitably contact | abutted to the 2nd side surface D of the to-be-joined metal member 1. FIG. In addition, when the weld metal T4 protrudes outside from the front surface A and the back surface B, it is preferable to excise the protruded part.

In addition, although the welding joining process was performed as mentioned above in this embodiment, you may change a process order and the form of welding suitably. For example, in the present embodiment, the first metal member 1a and the second metal member 1b are formed with grooves in advance. However, after the first metal member 1a and the second metal member 1b are abutted, the grooves are notched. It may be formed.
Moreover, after forming a ditch | groove previously also in the side surface of the 1st metal member 1a and the 2nd metal member 1b, after abutting the 1st metal member 1a and the 2nd metal member 1b, it fills with a weld metal. Good. Moreover, in this embodiment, although the recessed grooves K1-K4 were formed, it is not necessary to necessarily provide. Moreover, although the shape of the ditch | groove K1-the ditch | groove K4 is a cross sectional view rectangle in this embodiment, other shapes may be sufficient. Moreover, you may form the shape of the ditch | groove K1-the ditch | groove K4, for example so that it may expand to the center side of the to-be-joined metal member 1, and welding length may become long.

(3) First Main Joining Step In the first main joining step, friction stirring is performed from the surface A of the metal member 1 to be joined using the large rotary tool G. In the present embodiment, the first main joining step includes a tab material arranging step for arranging a pair of tab members on the metal member 1 to be joined, a temporary joining step for temporarily joining the metal member 1 to be joined and the tab material, and a large size. This includes a pilot hole forming step of forming a pilot hole at a position where the rotary tool G is to be inserted, and a first main bonding step of performing frictional stirring along the abutting portion J1 of the metal member 1 to be bonded.
Here, the tab material and the rotary tool used in the first main joining process will be described in detail.

  As shown in FIGS. 7A and 7B, the first tab member 2 and the second tab member 3 are arranged so as to sandwich the butted portion J1 of the metal member 1 to be joined, respectively. Attached to the metal member 1 to be joined and covers the weld metals T3 and T4 appearing on the first side C and the second side D, respectively. Although there is no restriction | limiting in particular in the material of the 1st tab material 2 and the 2nd tab material 3, In this embodiment, it forms with the metal material of the same composition as the to-be-joined metal member 1. FIG. Moreover, there is no restriction | limiting in particular also in the shape and dimension of the 1st tab material 2 and the 2nd tab material 3, In this embodiment, the thickness dimension is the same as the thickness dimension of the to-be-joined metal member 1 in the butt | matching part J1. I have to.

  Next, referring to FIG. 8, a small rotating tool F (hereinafter referred to as “small rotating tool F”) and a large rotating tool G (hereinafter referred to as “large rotating tool G”) used for friction stirring. This will be described in detail.

  A small rotary tool F shown in FIG. 8A is made of a metal material harder than the metal member 1 to be joined, such as tool steel, and protrudes from a shoulder F1 having a columnar shape and a lower end surface F11 of the shoulder F1. And a stirring pin (probe) F2. The size and shape of the small rotary tool F may be set in accordance with the material and thickness of the metal member 1 to be joined, but at least the large rotary tool G used in the first main joining step described later (( b) smaller than reference). In this way, since it is possible to perform the joining with a small load, it is possible to reduce the load applied to the friction stirrer during joining, and the friction stir can be smoothly performed even in a relatively complicated path. it can. Furthermore, since the moving speed (feeding speed) of the small rotating tool F can be made higher than the moving speed of the large rotating tool G, it is possible to reduce the work time and cost required for joining.

The lower end surface F11 of the shoulder F1 is a portion that plays a role of pressing the plastic fluidized metal and preventing scattering to the surroundings, and is formed in a concave shape in this embodiment. There is no particular limitation on the size of the outer diameter X ₁ of the shoulder F1, in this embodiment, is smaller than the outer diameter Y ₁ of the shoulder G1 of large rotating tools G.

The stirring pin F2 hangs down from the center of the lower end surface F11 of the shoulder F1, and is formed in a tapered truncated cone shape in this embodiment. In addition, a stirring blade engraved in a spiral shape is formed on the peripheral surface of the stirring pin F2. There is no particular limitation on the size of the outer diameter of the stirring pin F2, in the present embodiment, than the maximum outer diameter of the maximum outer diameter of the stirring pin G2 of (upper diameter) X ₂ is large rotating tool G (upper end diameter) Y ₂ It is small, and the minimum outer diameter (bottom diameter) X ₃ is smaller than the minimum outer diameter (bottom diameter) Y ₃ of the stirring pin G2. The length L _A of the stirring pin F2 is desirably smaller than the length L _B of the stirring pin G2 of the large rotary tool G (see FIG. 8B).

  A large rotary tool G shown in FIG. 8B is made of a metal material harder than the metal member 1 to be joined, such as tool steel, and protrudes from a shoulder G1 having a cylindrical shape and a lower end surface G11 of the shoulder G1. And a stirring pin (probe) G2.

  The lower end surface G11 of the shoulder G1 is formed in a concave shape like the small rotary tool F. The stirring pin G2 hangs down from the center of the lower end surface G11 of the shoulder G1, and in the present embodiment, is formed in a tapered truncated cone shape. In addition, a stirring blade engraved in a spiral shape is formed on the peripheral surface of the stirring pin G2.

  In the tab material arranging step, as shown in FIGS. 7A and 7B, a pair of tab materials are arranged on the first side surface C and the second side surface D of the bonded metal member 1. That is, the first tab member 2 is disposed in contact along the abutting portion J1 (welded metal T3) of the first side surface C. On the other hand, the 2nd tab material 3 is contact | abutted and arrange | positioned along the abutting part J1 (welded metal T4) of the 2nd side surface D. As shown in FIG. The first tab member 2 and the joining corners 2a and 2b of the metal member 1 to be joined are welded to temporarily join the first tab material 2 and the metal member 1 to be joined. Thereby, the opening at the time of the temporary joining process mentioned later can be prevented. Similarly, the second tab member 3 and the metal member 1 to be joined are temporarily joined by welding.

  In the temporary joining step, as shown in FIG. 9, the metal member to be joined 1, the first tab material 2, and the second tab material 3 are temporarily joined by friction stirring using a small rotary tool F. The temporary joining step includes a first temporary joining step in which friction stirring is performed along the abutting portion J3 between the metal member 1 to be joined and the second tab material 3, and a butt portion between the metal member 1 to be joined and the second tab material 3. This includes a second temporary joining step in which frictional stirring is performed along J2.

In the first temporary joining step, the small rotary tool F is rotated clockwise to the start position _SP1 set at an arbitrary point of the second tab member 3 and pressed (pressed), and the small rotation toward the start point s3 on the abutting portion J3. The tool F is moved relatively. When the starting point s3 is reached, the small rotating tool F is moved along the abutting portion J3 without detaching the small rotating tool F. When small rotary tool F reaches the end point e3 on the butting portion J3, a small rotating tool F intruded into the second tab member 3 side, thereby leaving a small rotary tool F at the end position E _P1. Thus, temporary joining can be efficiently performed by moving the small rotary tool F in the manner of one-stroke writing.

  In addition, when the small rotary tool F is rotated to the right, there is a possibility that a fine cavity defect may occur on the left side in the traveling direction of the small rotating tool F. It is desirable to set the positions of the start point s3 and the end point e3 so that the member 1 is positioned. If it does in this way, since it becomes difficult to generate | occur | produce a cavity defect in the to-be-joined metal member 1 side, it becomes possible to obtain a high quality joined body.

  Incidentally, when the small rotary tool F is rotated counterclockwise, there is a possibility that a fine cavity defect may occur on the right side in the traveling direction of the small rotating tool F. It is desirable to set the positions of the start point and end point of the second tab material joining step so that the member 1 is positioned. Specifically, although not shown, a starting point is provided at the position of the end point e3 when the small rotating tool F is rotated to the right, and an end point is provided at the position of the starting point s3 when the small rotating tool F is rotated to the right. Just do it.

  In addition, when the stirring pin F2 of the small rotary tool F enters the abutting portion J3, a force for separating the metal member 1 to be bonded and the second tab material 3 acts, but the metal member 1 to be bonded and the second tab material 3 are applied. Since the corners 3 a and 3 b formed by the above are temporarily joined by welding, no opening is generated between the metal member 1 to be joined and the second tab member 3.

  In the second temporary joining step, as shown in FIG. 9, the abutting portion J2 between the first tab member 2 and the metal member 1 to be joined is temporarily joined using the small rotary tool F. Since the second temporary bonding step is substantially the same as the first temporary bonding step, detailed description is omitted.

Under the hole forming step, as shown in FIG. 8 (b) is a step of forming a prepared hole P1 at the start position S _M1 of the friction stir in the single bonding step. In the prepared hole forming step to form a prepared hole P1 to S _M1 that is set on the first tab member second surface.

  The pilot hole P1 is provided for the purpose of reducing the insertion resistance (press-fit resistance) of the stirring pin G2 of the large rotary tool G, and is formed by expanding the diameter with a drill (not shown) in the present embodiment. . Although there is no restriction | limiting in particular in the form of the pilot hole P1, In this embodiment, it is cylindrical. In addition, in this embodiment, although the pilot hole P1 is formed in the 1st tab material 2, there is no restriction | limiting in particular in the position of the pilot hole P1, You may form in the 2nd tab material 3, and the butt | matching part J2 , J3 may be preferably formed on the extended line of the joint (boundary line) of the metal member 1 to be bonded that appears on the surface A side of the metal member 1 to be bonded as in the present embodiment. .

In the first main joining step, as shown in FIG. 10, friction stirring is performed from the surface A side of the metal member 1 to be joined along the abutting portion J1 (welded metal T1) using a large rotating tool G. In the first main joining step, the large rotary tool G is pushed into the start position _SM1 set on the first tab member 2, and the large rotary tool G is relatively moved without being detached, and the end position set on the second tab member 3 is reached. E Friction stir until _M1 . By the first main joining step, the surface side plasticized region W1 is formed along the abutting portion J1 of the metal member 1 to be joined.

Here, the relationship between the surface side plasticizing region W1 (large rotating tool G) and the groove K1 will be described with reference to FIG. 11 is a cross-sectional view taken along line III-III in FIG. The width Wa of the surface plasticized region W1 (outer diameter Y ₁ substantially equal to the shoulder G1) is larger than the width K _L of the groove K1. The depth W1b surface side plasticized region W1 is larger than the depth K _D of the groove K1. That is, since the interface between the bottom surface and both side surfaces of the groove K1 and the weld metal T1 is friction-stirred, the watertightness and airtightness of the metal member 1 to be bonded can be improved.

Here, if at least the tip of the surface side plasticizing region W1 and the bottom surface of the groove K1 are in contact with each other, the airtightness and watertightness can be improved. However, as in the present embodiment, the bottom surface of the groove K1 and It is preferable to frictionally stir the entire interface between both side surfaces and the weld metal T1. In the present embodiment, the distance G2b from the surface A to the lower end of the stirring pin G2 is larger than the depth K _D of the groove K1. Thereby, the friction stir of the interface of the ditch K1 and weld metal T1 can be carried out more certainly.

(4) Second Main Joining Step In the second main joining step, friction agitation is performed along the abutting portion J1 using the large rotary tool G on the back surface B of the metal member 1 to be joined. Since the second main joining step is substantially the same as the first main joining step, detailed description thereof is omitted. When the second main joining process is completed, the pair of tab members are cut from the metal member 1 to be joined.

  As described above, according to the joining method according to the present embodiment, welding is performed from the front surface A, the back surface B, the first side surface C, and the second side surface D of the butted portion J1 of the metal member 1 to be joined. The watertightness and airtightness of the bonded metal member 1 can be improved. Moreover, the joining strength of the to-be-joined metal member 1 can be raised by performing frictional stirring with respect to the abutting part J1.

  Moreover, after filling the groove K1 with the weld metal T1, the interface between the groove K1 and the weld metal T1 can be reliably sealed by performing frictional stirring.

[Second Embodiment]
The joining method according to the second embodiment is different from the first embodiment in that the first metal member and the second metal member are joined at a substantially right angle (L-shape in plan view).
In the joining method according to the present embodiment, the front surface A, the back surface B, and the first side surface with respect to the abutting portion J11 of the joined metal member 10 formed by abutting the side surface of the first metal member 10a and the end surface of the second metal member 10b While welding is performed from C and the second side surface D, friction stirring is performed from the front surface A and the back surface B.

  As shown in FIGS. 12 and 13, the bonded metal member 10 is formed by abutting a side surface 44 a of the first metal member 10 a having a rectangular cross-sectional view and an end surface 11 b of the second metal member 10 b having a rectangular cross-sectional view. . A butting portion J11 (see FIG. 12) is formed on the butting surface of the metal member 10 to be joined. In the present embodiment, the first metal member 10a and the second metal member 10b are metal materials having the same composition, for example, friction such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium alloy, magnesium, and magnesium alloy. It consists of a stirrable metal material. Although there is no restriction | limiting in particular in the shape and dimension of the 1st metal member 10a and the 2nd metal member 10b, It is desirable to make the thickness dimension in the butt | matching part J11 the same at least.

  On the end surface 11b side of the surface 12b of the second metal member 10b, a concave groove K11b is formed which continues from one side surface 14b to the other side surface 15b. Further, a concave groove K12b is formed on the end surface 11b side of the back surface 13b of the second metal member 1b so as to continue from one side surface 14b to the other side surface 15b. The concave groove K11b and the concave groove K12b have a rectangular shape in cross section and are formed with a predetermined depth and width.

  Next, the joining method according to this embodiment will be described. The joining method according to the present embodiment includes (1) a butting process, (2) a welding joining process, (3) a first regular joining process, and (4) a second regular joining process.

(1) Butting process In a butting process, the side surface 44a of the first metal member 10a and the end surface 11b of the second metal member 10b are butted together to form the metal member 1 to be joined. That is, in the abutting process, as shown in FIGS. 12 and 13, the surface 42a of the first metal member 10a and the surface 12b of the second metal member 10b are flush with each other, and the back surface 43a of the first metal member 10a The back surface 13b of the second metal member 10b is flush. Further, the end surface 45a of the first metal member 10a and the other side surface 15b of the second metal member 10b are flush with each other.

As shown in FIG. 14, one side surface 44a of the first metal member 10a and the groove K11b of the second metal member 10b are abutted to form a groove K11 having a bottom surface and a pair of side surfaces. Further, as shown in FIGS. 13 and 15, one side surface 44a of the first metal member 10a and the concave groove K12b of the second metal member 10b are brought into contact with each other, so that a concave groove K12 having a bottom surface and a pair of side surfaces is formed. Is formed. In addition, one side surface 44a of the first metal member 10a and one side surface 14b of the second metal member 10b are substantially perpendicular, and the corner I is formed.
In addition, let the surface of the to-be-joined metal member 10 be the surface A, a back surface is the back surface B, one side is the 1st side C, and the other side is the 2nd side D.

(2) Welding and joining step In the welding and joining step, welding is performed along the abutting portions exposed on the front surface A, the back surface B, the first side surface C, and the second side surface D of the metal member 1 to be joined. The welding joint process in this embodiment includes a first weld metal filling process for filling the groove K11 with the weld metal T11, and a first excision for cutting out a portion of the weld metal T11 that protrudes from the surface A of the metal member 10 to be joined. A step, a second weld metal filling step of filling the groove K12 with the weld metal T12, a second excision step of cutting a portion of the weld metal T12 that protrudes from the back surface B of the bonded metal member 10, and a first side surface C, a third groove forming step for forming the groove K13 along the abutting portion J11, a fourth groove forming step for forming the groove K14 along the abutting portion J11 on the second side surface D, A third weld metal filling step of filling the groove K13 with the weld metal T13, a third excision step of cutting a portion of the weld metal T13 protruding from the first side C of the metal member 10 to be joined, and welding to the groove K14. Metal T1 The includes a fourth weld metal filling step of filling, a fourth excision step of excising a portion protruding from the second side surface D of the joining metallic member 10 of the weld metal T14, the.

  In the first weld metal filling step, as shown in FIG. 14A, build-up welding is performed on the groove K11 formed on the surface A of the metal member 1 to be joined. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K11 with the weld metal T11. The overlay welding is preferably performed so that the weld metal T11 protrudes upward from the surface A. As shown in FIG. 14B, a portion of the weld metal T11 that protrudes upward from the surface A is defined as a built-up portion T11 '.

  In the first excision step, as shown in FIG. 14B, the build-up portion T11 'protruding from the surface A is excised using a known cutting tool. According to the first excision step, the surface A can be formed smoothly, and the large rotary tool G can be smoothly moved during the first main joining step described later. In addition, when the weld metal T11 protrudes from the first side surface C and the second side surface D, it is preferable to cut off the protruding portion.

  In the second weld metal filling step, although not specifically shown, overlay welding is performed on the groove K12 (see FIG. 15) formed on the back surface B of the metal member 1 to be joined. In overlay welding, for example, MIG welding or TIG welding is performed, and the groove K12 is filled with the weld metal T12 (see FIG. 15). The overlay welding is preferably performed such that the weld metal T2 protrudes from the back surface B. The part which protrudes from the back surface B among welding metal T12 is made into a built-up part.

  The second excision step is a step of excising the built-up portion protruding from the back surface B using a known cutting tool. According to the second excision step, the back surface B can be formed smoothly, and the large rotary tool G can be smoothly moved during the second main joining step described later. In addition, when the weld metal T12 protrudes from the first side surface C and the second side surface D, it is preferable to cut off the protruding portion.

  In the third concave groove forming step, as shown in FIG. 15, the concave groove K13 is formed on the end surface side of one side surface 14b of the second metal member 10b using a known end mill or the like along the abutting portion J1. The concave groove K13 has a rectangular shape in cross section and is continuously formed from the front surface A to the back surface B. The concave groove K13 is formed with a depth and a width substantially the same as the concave groove K11. Moreover, the unwelded area | region is exposed to the bottom face of the ditch | groove K13 among the butt | matching parts J1.

  In the fourth concave groove forming step, as shown in FIG. 15, the concave groove K14 is formed along the abutting portion J11 on the end surface side of the other side surface 15b of the second metal member 10b using a known end mill or the like. The concave groove K14 is rectangular in a sectional view, and is continuously formed from the front surface A to the back surface B. The concave groove K14 is formed with a depth and width substantially equal to the concave groove K11. Moreover, the unwelded area | region is exposed to the bottom face of the ditch | groove K14 among the butt | matching parts J11.

  In the third weld metal filling step, as shown in FIG. 16 (a), the groove K13 formed on one side surface 14b of the second metal member 10b (the first side surface C of the metal member 1 to be joined) has a thickness. Perform prime welding. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K13 with the weld metal T13. The overlay welding is preferably performed so that the weld metal T13 protrudes from the first side surface C. As shown in FIG. 16B, a portion of the weld metal T13 that protrudes from the first side surface C is referred to as a built-up portion T13 '.

  The third excision step is a step of excising the built-up portion T13 'protruding from the first side surface C using a known cutting tool. According to the third cutting step, the first side surface C can be formed smoothly. Thereby, in the tab material arrangement | positioning process mentioned later, a tab material can be suitably contact | abutted to the 1st side surface C of the to-be-joined metal member 10. FIG. In addition, when the weld metal T13 protrudes outside from the front surface A and the back surface B, it is preferable to cut off the protruding portion.

  In the fourth weld metal filling step, although not specifically shown, overlay welding is performed on the concave groove K14 (see FIG. 16) formed on the second side face D of the metal member 1 to be joined. In overlay welding, for example, MIG welding or TIG welding is performed to fill the groove K14 with the weld metal T14 (see FIG. 17). The overlay welding is preferably performed such that the weld metal T14 protrudes from the second side face D. The part which protrudes rather than the 2nd side D among welding metal T14 is made into a built-up part.

The fourth excision step is a step of excising the built-up portion protruding from the second side surface D using a known cutting tool. According to the fourth excision step, the second side face D can be formed smoothly. Thereby, in the tab material arrangement | positioning process mentioned later, a tab material can be suitably made to contact | abut to the 2nd side surface D of the to-be-joined metal member 10. FIG. In addition, when the weld metal T14 protrudes outside from the front surface A and the back surface B, it is preferable to cut off the protruding portion.
(3) First Main Joining Step In the first main joining step, friction stirring is performed from the surface A of the metal member 1 to be joined using the large rotary tool G. In the present embodiment, the first main joining step includes a tab material arranging step for arranging a pair of tab members on the metal member 10 to be joined, a temporary joining step for temporarily joining the metal member 10 to be joined and the tab material, and a large size. This includes a pilot hole forming step of forming a pilot hole at a planned insertion position of the rotary tool G, and a first main joining step of performing frictional stirring from the surface A along the abutting portion J1 of the metal member 10 to be joined.
Here, the tab material used in the first main joining step will be described in detail.

  As shown in FIG. 17, the first tab member 4 and the second tab member 5 are arranged so as to sandwich the abutting portion J11 of the bonded metal member 10, and are attached to the bonded metal member 10, respectively. Then, the weld metals T13 and T14 appearing on the first side C and the second side D are covered. Although there is no restriction | limiting in particular in the material of the 1st tab material 4 and the 2nd tab material 5, In this embodiment, it forms with the metal material of the same composition as the to-be-joined metal member 10. FIG. Further, the shape and dimensions of the first tab material 4 and the second tab material 5 are not particularly limited, but in this embodiment, the thickness dimension is the same as the thickness dimension of the metal member 10 to be joined at the abutting portion J11. I have to.

  In the tab material arranging step, a pair of tab materials are arranged on the first side surface C and the second side surface D of the metal member 10 to be joined, as shown in FIG. That is, the first tab member 4 is disposed in contact with the abutting portion J11 (welded metal T14) of the second side surface D. On the other hand, the second tab member 5 is disposed in contact with the first metal member 10a and the second metal member 10b (welded metal T13) in the corner I. The first tab member 4 and the joining corners 4a and 4b of the metal member 10 to be joined are welded to temporarily join the first tab material 4 and the metal member 10 to be joined. Thereby, the opening at the time of the temporary joining process mentioned later can be prevented. Similarly, the second tab member 5 and the metal member 10 to be joined are temporarily joined by welding.

  In the temporary joining step, as shown in FIG. 18, the metal member 10 to be joined, the first tab material 4 and the second tab material 5 are temporarily joined by friction stirring using a small rotary tool F. The temporary joining step includes a first temporary joining step in which friction stirring is performed along the abutting portion J14 between the metal member to be joined 10 and the first tab member 4, and a butt portion between the metal member to be joined 10 and the second tab member 5. This includes a second temporary joining step in which frictional stirring is performed along J15 and J15.

In the first temporary joining step, the small rotary tool F is rotated to the right at the start position _SP3 set at an arbitrary point of the first tab member 4 and pressed (pressed), and the small rotation toward the start point s4 on the abutting portion J14. The tool F is moved relatively. When the starting point s4 is reached, the small rotating tool F is moved along the abutting portion J14 without detaching the small rotating tool F. When small rotary tool F reaches the end point e4 on butting portion J14, a small rotating tool F intruded into the first tab member 4 side, thereby leaving a small rotary tool F at the end position E _P3. Thus, temporary joining can be efficiently performed by moving the small rotary tool F in the manner of one-stroke writing.

  In addition, when the small rotary tool F is rotated to the right, there is a possibility that a fine cavity defect may occur on the left side in the traveling direction of the small rotating tool F. It is desirable to set the positions of the start point s4 and the end point e4 so that the member 10 is positioned. If it does in this way, since it becomes difficult to generate | occur | produce a cavity defect in the to-be-joined metal member 10 side, it becomes possible to obtain a high quality bonded body.

  Incidentally, when the small rotary tool F is rotated counterclockwise, there is a possibility that a fine cavity defect may occur on the right side in the traveling direction of the small rotating tool F. It is desirable to set the positions of the start point and end point of the second tab material joining step so that the member 10 is positioned. Specifically, although not shown, a starting point is provided at the position of the end point e4 when the small rotating tool F is rotated to the right, and an end point is provided at the position of the starting point s4 when the small rotating tool F is rotated to the right. Just do it.

  In addition, when the stirring pin F2 of the small rotary tool F enters the abutting portion J14, a force for separating the bonded metal member 10 and the first tab material 4 acts, but the bonded metal member 10 and the first tab material 4 Since the corners 4a and 4b formed by the above are temporarily joined by welding, no openings are generated between the metal member to be joined 10 and the first tab member 4.

In the second temporary joining step, as shown in FIG. 18, the abutting portions J15 and J15 between the first tab member 4 and the metal member 10 to be joined are temporarily joined using a small rotary tool F. The small rotary tool F is rotated to the right at the start position _SP4 arbitrarily set on the second tab member 5 and pushed (pressed), and the small rotary tool F is relatively moved toward the start point s5 on the abutting portion J15. When the starting point s5 is reached, the small rotating tool F is moved along the abutting portion J15 without detaching the small rotating tool F. When the small rotating tool F reaches the change point h5 (entrance corner I) on the abutting portion J15, the small rotating tool F is moved toward the end point e5 of the abutting portion J15. When the small rotary tool F reaches the end point e5, the small rotary tool F enters the second tab member 5 as it is, and the small rotary tool F is detached from the second tab member 5 at the end position _EP4 . Thus, temporary joining can be efficiently performed by moving the small rotary tool F in the manner of one-stroke writing.

Although not specifically illustrated in the pilot hole forming step, the pilot hole P1 is formed at the friction stirring start position in the first main joining step. In the prepared hole forming step to form a prepared hole P1 to S _M2 set in the surface of the first tab member 4.

  The pilot hole P1 is provided for the purpose of reducing the insertion resistance (press-fit resistance) of the stirring pin G2 of the large rotary tool G, and is formed by expanding the diameter with a drill (not shown) in the present embodiment. Although there is no restriction | limiting in particular in the form of the pilot hole P1, In this embodiment, it is cylindrical. In the present embodiment, the pilot hole P1 is formed in the first tab member 4, but the position of the pilot hole P1 is not particularly limited, and may be formed in the second tab member 5, or the abutting portion J14. , J15 may be preferably formed on the extended line of the joint (boundary line) of the metal member 10 to be bonded that appears on the surface A side of the metal member 10 to be bonded as in the present embodiment. .

In the first main joining step, as shown in FIG. 19, friction stirring is performed from the surface A side of the metal member 10 to be joined along the abutting portion J11 using a large rotating tool G. In the first main joining step, the large rotary tool G is pushed into the start position _SM2 set on the first tab member 4, and the large rotary tool G is rubbed to the end position E _M2 set on the second tab member 5 without being detached. Stir.
That, push the large rotating tool G to the starting position S _M2, relatively moving large rotating tool G toward the start point s6. When the large rotary tool G reaches the start point s6, the large rotary tool G is moved along the abutting portion J11 toward the end point e6 without being detached. When the large rotary tool G reaches e6, the large rotary tool G is moved to the end position E _M2 set on the second tab member 5 and separated. By the first main joining step, the surface side plasticized region W11 is formed along the abutting portion J11 of the metal member 10 to be joined.

Here, the relationship between the surface side plasticizing region W11 (large rotating tool G) and the groove K11 will be described with reference to FIG. 20 is a sectional view taken along line VI-VI in FIG. The width Wa / 2 (substantially equivalent to the outer diameter Y _{1/2 of the} shoulder G1) of the surface side plasticizing region W11 is formed to be larger than the width K _{H of the} concave groove K11. The depth W11b surface side plasticized region W11 is larger than the depth _{K N} of the groove K11. That is, the watertightness and airtightness of the metal member 10 to be bonded can be improved by friction stirring the interface between the bottom surface and both side surfaces of the groove K11 and the weld metal T1. Here, if at least the end of the surface side plasticizing region W11 and the bottom surface of the groove K11 are in contact with each other, the airtightness and watertightness can be improved. However, as in the present embodiment, the bottom surface of the groove K11 and It is preferable to frictionally stir the entire interface between both side surfaces and the weld metal T11. In the present embodiment, the distance G2b from the surface A to the lower end of the stirring pin G2 is larger than the depth K _N of the groove K11. Thereby, the friction stir of the interface of the ditch K11 and weld metal T11 can be carried out more reliably.

(4) Second Main Joining Step In the second main joining step, as shown in FIG. 21, friction stirring is performed using the large rotary tool G on the back surface B of the metal member 10 to be joined. That is, friction stirring is performed along the abutting portion J11 without detaching the large rotary tool G from the start position S _M3 set to the first tab member 4 to the end position E _M3 . Since the second main joining step is substantially the same as the first main joining step, detailed description thereof is omitted. When the second main joining process is completed, the pair of tab members are cut from the metal member 10 to be joined.

  As described above, according to the joining method according to the present embodiment, welding is performed from the front surface A, the back surface B, the first side surface C, and the second side surface D of the abutting portion J11 of the metal member 10 to be joined. It is possible to improve the water tightness and air tightness of the metal member 10 to be joined. Moreover, the joining strength of the to-be-joined metal member 10 can be raised by performing frictional stirring with respect to the abutting part J1.

  In addition, after filling the groove K11 with the weld metal T11, the interface between the groove K11 and the weld metal T11 can be reliably sealed by performing frictional stirring in the first main joining step and the second main joining step. it can.

The embodiment of the present invention has been described above, but the present invention is not limited to this, and can be appropriately changed without departing from the spirit of the present invention. For example, after performing the welding joining process, friction stirring may be performed on the first side surface C and the second side surface D using the large rotary tool G. Further, as shown in FIG. 2, the concave grooves K1a, K1b and the like of the first metal member 1a and the second metal member 1b are formed on the front and back surfaces of each member. May be. Moreover, the process order in this embodiment is an illustration to the last, and another order may be sufficient as it.
Moreover, when a tunnel-like cavity defect occurs in the front surface side plasticized region and the back surface side plasticized region, it is preferable to seal the cavity defect by welding.

It is the perspective view which showed the joining method which concerns on 1st embodiment. It is the figure which showed the to-be-joined metal member which concerns on 1st embodiment, Comprising: (a) is a disassembled perspective view, (b) is a top view. (A) is the top view which showed the 1st weld metal filling process which concerns on 1st embodiment, Comprising: (b) is the II sectional view taken on the line of (a). It is the perspective view which showed the 2nd excision process after 1st embodiment. It is the perspective view which showed the 3rd ditch formation process and 4th ditch formation process which concern on 1st embodiment. (A) is the top view which showed the 3rd weld metal filling process which concerns on 1st embodiment, Comprising: (b) is the II-II sectional view taken on the line of (a). It is the figure which showed the tab material arrangement | positioning process which concerns on 1st embodiment, (a) is a perspective view, (b) is a top view. (A) is the side view which showed the small rotation tool, (b) is the side view which showed the large rotation tool. It is the top view which showed the temporary joining process which concerns on 1st embodiment. It is the top view which showed the 1st main joining process which concerns on 1st embodiment. It is the III-III sectional view taken on the line of FIG. It is the perspective view which showed the joining method which concerns on 2nd embodiment. It is a disassembled perspective view of the to-be-joined metal member which concerns on 2nd embodiment. (A) is the top view which showed the 1st weld metal filling process which concerns on 2nd embodiment, Comprising: (b) is the IV-IV sectional view taken on the line of (a). It is the perspective view which showed the 3rd ditch formation process which concerns on 2nd embodiment. (A) is the perspective view which showed the 3rd weld metal filling process which concerns on 2nd embodiment, (b) is the VV sectional view taken on the line of (a). It is the perspective view which showed the tab material arrangement | positioning process which concerns on 2nd embodiment. It is the top view which showed the temporary joining process which concerns on 2nd embodiment. It is the top view which showed the 1st main joining process which concerns on 2nd embodiment. It is the VI-VI sectional view taken on the line of FIG. It is the top view which showed the 2nd main joining process which concerns on 2nd embodiment. It is the perspective view which showed the conventional joining method. It is the perspective view which showed the conventional joining method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal member to be joined 1a 1st metal member 1b 2nd metal member 2 1st tab material 3 2nd tab material A surface B back surface C 1st side surface D 2nd side surface F small rotation tool G large rotation tool J butt part K concave Groove P1 Pilot hole T Weld metal W Plasticization region

Claims (10)

A butting step of matching the end face of the first metal member and the end face of the second metal member;
A welding joining step of performing welding from the front surface, the back surface and the side surface to the abutting portion of the metal member to be joined formed in the abutting step;
After the welding and joining step, a first main joining step in which friction stir is performed from the surface of the metal member to be joined to the butt portion;
After the first main joining step, the second main joining step of performing friction stirring from the back surface of the metal member to be joined to the abutting portion,
In the first main joining process, while friction stir the weld metal formed in the welding joining process and the metal member to be joined,
In the second main joining step, the welding metal formed in the welding joining step and the metal member to be joined are frictionally stirred.   2. The weld metal filling step according to claim 1, wherein the weld metal filling step includes a weld metal filling step of filling a concave groove formed along the abutting portion with the weld metal on a side surface of the metal member to be joined. Joining method.   The weld welding step includes a weld metal filling step of filling the weld metal into a concave groove formed along the abutting portion on at least one of the front surface and the back surface of the metal member to be joined. Claim | item 1 or the joining method of Claim 2.   The depth of the plasticized region formed in the first main joining step and the depth of the plasticized region formed in the second main joining step are the depths of the concave grooves formed on the front surface and the back surface of the metal member to be joined. The bonding method according to claim 3, wherein the bonding method is larger than the height. A butting step of abutting the side surface of the first metal member and the end surface of the second metal member;
A welding joining step of performing welding from the front surface, the back surface and the side surface to the abutting portion of the metal member to be joined formed in the abutting step;
After the welding and joining step, a first main joining step in which friction stir is performed from the surface of the metal member to be joined to the butt portion;
After the first main joining step, the second main joining step of performing friction stirring from the back surface of the metal member to be joined to the abutting portion,
In the first main joining process, while friction stir the weld metal formed in the welding joining process and the metal member to be joined,
In the second main joining step, the welding metal formed in the welding joining step and the metal member to be joined are frictionally stirred.   The weld welding step includes a weld metal filling step of filling the weld metal into a groove formed along the abutting portion on the side surface of the end surface of the second metal member. The joining method described in 1.   The weld welding step includes a weld metal filling step of filling the weld metal into a concave groove formed along the abutting portion on at least one of the front surface and the back surface of the metal member to be joined. Claim | item 5 or the joining method of Claim 6.   The depth of the plasticized region formed in the first main joining step and the depth of the plasticized region formed in the second main joining step are the depths of the concave grooves formed on the front surface and the back surface of the metal member to be joined. The bonding method according to claim 7, wherein the bonding method is larger than the height.   The joining method according to any one of claims 1 to 8, further comprising a cutting step of cutting out portions protruding from a front surface, a back surface, and a side surface of the metal member to be joined in the weld metal after the welding joining step. . The joining method according to any one of claims 1 to 9, wherein a pilot hole is formed in advance at a planned insertion position of the rotary tool used in the friction stirring.

Images