JP2009039780A - Joining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining method in which friction stirring is performed in a butted part between metallic members from their surface side and rear side and in which airtightness and watertightness can be improved between both sides of the metallic members. <P>SOLUTION: This is a joining method in which friction stirring is performed for a metallic members 1 to be joined. The method is characterized in that it includes: a first normal welding stage in which friction stirring is performed on the surface A of the metallic members 1 to be joined, at the butted part J1 between the first and the second metallic member 1a, 1b; a second normal welding stage in which friction stirring is performed on the rear side B; a recessed groove forming stage in which a recessed groove K is formed in the butted part J1 relating to the first and the second side face C, D of the metallic members 1 to be joined; and a joint member welding stage in which friction stirring is performed in a butted part between the recessed groove K and a joint member U. <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. It is what is joined. In general, the rotating tool is formed by protruding a stirring pin (probe) on the lower end surface of a shoulder portion having a cylindrical shape.

20 and 21 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. 20, 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, the conventional joining method 100 performs friction stir welding 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 is a plasticized region formed by friction stir welding. It joins so that the center part of the thickness direction of 105,106 may contact. 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, in the conventional example shown in FIG. 20, in the plasticized regions 105 and 106, there is a possibility that a cavity defect 109 continuous from one side surface 107 to the other side surface 108 occurs. Furthermore, when the front surface 102 and the back surface 103 are friction-stirred, there is a possibility that an oxide film formed on the side surface 107 and the side surface 108 is caught inside the metal member 111. The tunnel-like cavity defect 109 and the oxide film contribute to a decrease in watertightness and airtightness between the side surface 107 and the side surface 108 of the metal members 101 and 111.

  On the other hand, as shown in FIG. 21, 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 formed. There is a possibility that a plasticized region will 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 plasticizing region 105 is obtained. , 106 cannot be brought into contact with the central portion in the thickness direction, and a gap (unplasticized region 119) is generated in the central portion of the abutting portion 104. Thus, when the unplasticized area | region 119 which continues from the one side surface 107 to the other side surface 108 arises, there existed a problem that the watertightness and airtightness between the side surface 107 and the side surface 108 fell further.

  Here, if the length of the stirring pin of the rotary tool is increased according to the thickness of the metal member 111, the metal members 111 can be joined together 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 this point of view, the present invention can perform the friction stir welding of the abutting portions between the metal members from the front side and the back side of the metal member and improve the air tightness and water tightness between the both side surfaces of the metal member. It is an object to provide a simple joining method.

  A joining method according to the present invention that solves such a problem is a joining method in which a rotating tool is moved with respect to a metal member to be joined formed by abutting a first metal member and a second metal member to perform friction stirring. A first main joining step in which friction stir is performed on the surface of the metal member to be joined to the abutting portion between the first metal member and the second metal member, and the metal to be joined to the abutting portion. A second main joining step in which frictional stirring is performed on the back surface of the member; a concave groove forming step in which a concave groove is formed along the abutting portion of the side surface of the metal member to be joined; and a joint member is disposed in the concave groove And a joint member joining step of performing friction stirring on the abutting portion between the concave groove and the joint member.

  According to such a joining method, by forming the concave groove on the side surface of the metal member to be joined, it is possible to remove an oxide film that may be caught on the side surface of the metal member to be joined. Further, by performing frictional stirring on the abutting portion between the concave groove and the joint member disposed in the concave groove, a tunnel-like cavity defect that may be exposed on the side surface of the metal member to be bonded, or the metal to be bonded It is possible to cover and seal the oxide film which may be wound on the side surface of the member. Thereby, the airtightness and watertightness between the both sides | surfaces of a to-be-joined metal member can be improved. Moreover, the joint strength of the said part can be raised by performing friction stirring with respect to the butt | matching part of the said ditch | groove and a coupling member.

  Moreover, this invention is exposed between the surface side plasticization area | region formed by said 1st main joining process in the said ditch | groove, and the back surface side plasticization area | region formed by said 2nd main joining process. It is preferable to seal the unplasticized region.

  According to this joining method, the joint member is disposed in the unplasticized region exposed in the recessed groove formed on the side surface, and the unplasticized region is obtained by friction stirring the abutting portion between the joint member and the recessed groove. Can be sealed. Thereby, the airtightness and watertightness between the both side surfaces of a to-be-joined metal member can be improved more.

  Moreover, it is preferable to form the both end surfaces of the joint member according to the present invention flush with the front surface and the back surface of the metal member to be joined. According to such a joining method, the tunnel-like cavity defect, the oxide film, and the unplasticized region can be reliably sealed, and the front surface and the back surface can be formed flat.

  Moreover, it is preferable to form so that the depth of the side surface plasticization area | region formed at the said joint member joining process based on this invention may become larger than the thickness of the said joint member. According to such a joining method, since friction stir is performed over the entire length in the thickness direction at the abutting portion between the concave groove and the joint member, the air tightness and water tightness between both side surfaces of the metal member to be joined are further improved. Can be made.

  Moreover, it is preferable that this invention includes the 1st welding repair process of sealing at least one of the cavity defect exposed to the bottom face of the said ditch | groove, and the said unplasticized area | region with a weld metal after the said ditch | groove formation process. According to such a joining method, since the cavity defect and the unplasticized region can be sealed with the weld metal before covering the concave groove with the joint member, the airtightness and watertightness between the both side surfaces of the metal member to be joined are improved. This can be further improved.

  Moreover, this invention seals at least one of the cavity defect exposed to the said surface and the said back surface by the said joint member joining process, and the oxide film wound by the said joint member joining process with the weld metal after the said joint member joining process. It is preferable to include a second welding repair step. According to such a joining method, since the cavity defect and oxide film in the plasticized region formed by the joint member joining process can be sealed with the weld metal, the airtightness and watertightness of the front and back surfaces of the metal member to be joined can be reduced. Can be increased.

  Moreover, it is preferable to make the width | variety of the said ditch | groove which concerns on this invention smaller than the width | variety of the said surface side plasticization area | region and the said back surface plasticization area | region. According to such a joining method, it is possible to reduce the labor for forming the concave groove, and it is possible to reduce the joint member, thereby reducing the member cost.

  In the present invention, it is preferable that a pilot hole is formed in advance at a planned insertion position of the rotary tool. According to such a joining method, it is possible to reduce press-fit resistance when the rotary tool is pushed in. Thereby, while improving the precision of friction stir welding, a joining operation can be performed rapidly.

  According to the joining method according to the present invention, the abutting portions between the metal members can be frictionally stirred from the front surface side and the back surface side of the metal members, and the air tightness and water tightness between both side surfaces of the metal members can be improved.

In the joining method according to the present embodiment, as shown in FIG. 1A, the front surface A and the back surface B of the metal member 1 to be joined formed by abutting the first metal member 1a and the second metal member 1b are friction-stirred. As shown in FIG. 1B, the joint member U is disposed in the concave groove K and the concave grooves are formed on both side surfaces of the metal member 1 to be joined. The abutting portion between K and the joint member U is joined by friction stirring.
First, the metal member 1 to be bonded of the bonding method according to the present embodiment will be described in detail, and the first tab material 2 and the second tab material 3 used when bonding the metal member 1 to be bonded will be described in detail. To do.

As shown in FIGS. 2A and 2B, the metal member 1 to be joined includes a first metal member 1a and a second metal member 1b that are rectangular in cross-section, and each end face is abutted. Thus, the abutting portion J1 is formed. 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.
In addition, as shown in FIG. 1, let the surface of the to-be-joined metal member 1 be the surface A, the back surface is the back surface B, one side surface is the 1st side surface C, and the other side surface is the 2nd side surface D. Also, the vertical and horizontal directions in the present embodiment follow the arrows in FIG.

  As shown in FIGS. 2A and 2B, 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, The seam (boundary line) between the first metal member 1a and the second metal member 1b, which is attached to the bonded metal member 1 and appears on the first side surface C and the second side surface D, is obscured. 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. 4, a rotary tool F used in the temporary joining process (hereinafter referred to as “temporary joining rotary tool F”) and a rotary tool G used in the main joining process (hereinafter referred to as “main joining rotary tool”). G ”) will be described in detail.

  The temporary joining rotary tool F shown in FIG. 4A is made of a metal material harder than the metal member 1 to be joined, such as tool steel, and has a cylindrical shoulder portion F1 and a lower end face F11 of the shoulder portion F1. And an agitating pin (probe) F2 provided in a protruding manner. The size and shape of the temporary bonding rotary tool F may be set according to the material and thickness of the metal member 1 to be bonded, but at least the main bonding rotating tool G used in the first main bonding step described later. (Refer to FIG. 4B). This makes it possible to perform temporary bonding with a load smaller than that of the main bonding, so that it is possible to reduce the load applied to the friction stirrer at the time of temporary bonding. Since the moving speed (feeding speed) can be made faster than the moving speed of the main joining rotary tool G, the working time and cost required for temporary joining can be reduced.

The lower end surface F11 of the shoulder portion 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 portion F1, in this embodiment, is smaller than the outer diameter Y ₁ of the shoulder portion G1 of the joining rotation tool G.

The stirring pin F2 hangs down from the center of the lower end surface F11 of the shoulder portion F1, and is formed into 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, the maximum outer diameter of the stirring pin G2 of the maximum outer diameter (upper diameter) X ₂ is rotated for the welding tool G (upper end diameter) Y ₂ smaller than, 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 ₂ of the stirring pin F2 is preferably smaller than the stirring pin G2 of the joining rotation tool G length L _{1 (see} FIG. 4 (b)).

  A main rotating tool G for joining shown in FIG. 4B is made of a metal material harder than the metal member 1 to be joined, such as tool steel, and has a cylindrical shoulder portion G1 and a lower end face G11 of the shoulder portion G1. And an agitating pin (probe) G2 provided in a protruding manner.

  The lower end surface G11 of the shoulder portion G1 is formed in a concave shape like the temporary joining rotary tool F. The stirring pin G2 hangs down from the center of the lower end surface G11 of the shoulder portion G1, and is formed into 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 G2.

  Hereinafter, the joining method according to the present embodiment will be described in detail. The bonding method according to this embodiment includes (1) a first preparation step, (2) a first preliminary step, (3) a first main bonding step, (4) a second preparation step, and (5) a first. Two preliminary steps, (6) second main joining step, (7) tab material cutting step, (8) concave groove forming step, (9) first welding repair step, (10) third preparatory step, ( 11) a first joint member joining step, (12) a fourth preparation step, (13) a second joint member joining step, (14) a tab material cutting step, and (15) a second welding repair step.

  In addition, as shown in FIG. 1, (2) 1st preliminary process and (3) 1st this joining process are processes performed in the surface A, (5) 2nd preliminary process and (6 ) The second main joining process is a process executed on the back surface B. Moreover, it is a process performed in the (8) recessed groove formation process, (9) 1st welding repair process, the 1st side surface C, and the 2nd side surface D. The (11) first joint member joining step is a step executed on the first side surface C, and the (13) second joint member joining step is a step executed on the second side surface D. Moreover, (15) 2nd welding repair process is a process performed in the surface A and the back surface B. FIG.

(1) First Preparation Step The first preparation step will be described with reference to FIGS. A 1st preparation process is a process of preparing the contact member (the 1st tab material 2 and the 2nd tab material 3) in which the start position and completion | finish position of the friction stirring of the to-be-joined metal member 1 are provided. In the present embodiment, the first preparation step includes a butting step of butting the first metal member 1a and the second metal member 1b, and the first tab material 2 and the second on both sides of the butting portion J1 of the metal member 1 to be joined. A tab material arranging step of arranging the tab material 3, and a temporary welding step of temporarily joining the first tab material 2 and the second tab material 3 to the metal member 1 to be joined by welding.

(1-1) Butting Step In the matching step, as shown in FIG. 2B, the end surface 11b of the second metal member 1b is brought into close contact with the end surface 11a of the first metal member 1a. Moreover, as shown in FIG. 3 etc., 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 further, the back surface 13a of the first metal member 1a and the back surface of the second metal member 1b. 13b is flush. Similarly, the first side surface 14a of the first metal member 1a and the first side surface 14b of the second metal member 1b are flush with each other, and the second side surface 15a of the first metal member 1a and the second side of the second metal member 1b. The side surface 15b is flush.

  That is, the surface A is formed by the surface 12a of the first metal member 1a and the surface 12b of the second metal member 1b, and the back surface B is formed by the back surface 13a of the first metal member 1a and the back surface 13b of the second metal member 1b. The first side surface C is formed by the first side surface 14a of the first metal member 1a and the first side surface 14b of the second metal member 1b, and the second side surface D is the second side surface 15a of the first metal member 1a. It is formed by the second side surface 15b of the second metal member 1b.

(1-2) Tab material arrangement process In the tab material arrangement process, as shown in FIGS. 2A and 2B, the first tab material 2 is arranged on the second side face D side of the abutting portion J1, The contact surface 21 is brought into contact with the second side surface D. Furthermore, the 2nd tab material 3 is arrange | positioned in the 1st side C of the abutting part J1, and the contact surface 31 is made to contact | abut to the 1st side C. FIG. At this time, as shown in FIG. 3B, the surface 22 of the first tab member 2 and the surface 32 of the second tab member 3 are flush with the surface A of the metal member 1 to be joined, and the first tab. The back surface 23 of the material 2 and the back surface 33 of the second tab material 3 are flush with the back surface B of the bonded metal member 1.

(1-3) Temporary welding process In the temporary welding process, as shown to (a) and (b) of FIG. 2, the corners 2a and 2b formed by the to-be-joined metal member 1 and the 1st tab material 2 are shown. Are welded to temporarily join the metal member 1 and the first tab member 2 together. Furthermore, the corners 3 a and 3 b formed by the metal member 1 and the second tab material 3 are welded to temporarily bond the metal member 1 and the second tab material 3 to each other.
In addition, welding may be performed continuously over the entire length of the corners 2a, 2b and 3a, 3b, or welding may be performed intermittently. Further, in the first preparation step, when the temporary welding step is omitted, the abutting step and the tab material arranging step may be performed on a frame of a friction stirrer (not shown).

(2) First Preliminary Step The first preliminary step is a step performed prior to the first main joining step, and in the present embodiment, on the surface A side, the metal member 1 and the first tab member to be joined. (2-1) the first tab material joining step, the temporary joining step J1 of the metal member 1 to be joined (2-2) the temporary joining step, and the metal member 1 to be joined. (2-3) A pilot hole is formed at the friction stir start position in the second tab material joining step and the first main joining step (2-4). A pilot hole forming step.

In the first preliminary process, as shown in FIG. 6, one temporary joining rotary tool F is moved so as to form a one-stroke writing trajectory (bead), and the abutting portions J2, J1, J3 are moved. Continuous friction stir. That is, the stirring pin F2 (see FIG. 4A) of the temporary joining rotary tool F inserted at the friction stirring start position _SP1 is moved to the end position _EP1 without being removed halfway. In this embodiment, the first tab member 2 is provided with the friction stirring start position S _P1 and the second tab member 3 is provided with the end position E _P1 . However, the positions of the start position S _P1 and the end position E _P1 are the same. It is not intended to limit. In the present embodiment, the rotation directions of the temporary welding rotary tool F and the main welding rotary tool G are all rotated clockwise. In this way, by unifying the rotation directions of the temporary joining rotary tool F and the main joining rotary tool G, it is possible to save labor.

The procedure of friction stirring in the first preliminary process of this embodiment will be described in more detail with reference to FIGS.
First, the metal member 1 to be joined that has undergone the temporary welding process is fixed to a frame of a friction stirrer (not shown). Then, as shown in (a) of FIG. 5, positions the rotary tool F for temporary bonding directly on the start position S _P1 provided in place of the first tab member 2, followed by the rotary tool F for temporary joining It is lowered while rotated clockwise presses the start position S _P1 stirring pin F2 with. The rotational speed of the rotary tool F for temporary joining is set according to the size and shape of the stirring pin F2, the material and thickness of the joined metal member 1 to be frictionally stirred, etc. It is set within a range of 500 to 2000 (rpm).

  When the stirring pin F2 comes into contact with the surface 22 of the first tab member 2, the metal around the stirring pin F2 is plastically fluidized by frictional heat, and the stirring pin F2 is moved to the first tab as shown in FIG. Inserted into the material 2.

  When the entire stirring pin F2 enters the first tab member 2 and the entire lower end surface F11 of the shoulder portion F1 contacts the surface 22 of the first tab member 2, as shown in FIG. While rotating F, it is relatively moved toward the starting point s2 of the first tab material joining step.

  The moving speed (feeding speed) of the temporary bonding rotary tool F is set according to the size and shape of the stirring pin F2, the material and thickness of the metal member 1 to be bonded and the like to be frictionally stirred, In many cases, it is set within a range of 100 to 1000 (mm / min). The rotational speed at the time of movement of the temporary joining rotary tool F is the same as or lower than the rotational speed at the time of insertion. Note that when the temporary welding rotary tool F is moved, the axis of the shoulder portion F1 may be slightly inclined to the rear side in the traveling direction with respect to the vertical line. The direction of the joining rotary tool F can be easily changed, and complicated movement is possible. When the rotary tool F for temporary joining is moved, the metal around the stirring pin F2 is plastically fluidized sequentially, and the metal that has been plastically fluidized is hardened again at a position away from the stirring pin F2.

  When the frictional stirrer is continuously performed up to the start point s2 of the first tab material joining process by relatively moving the temporary tool F for temporary joining, the first tab material is joined as it is without removing the temporary tool for rotation F at the start point s2. Move to the process.

(2-1) First Tab Material Joining Step In the first tab material joining step, friction agitation is performed on the abutting portion J2 between the first tab material 2 and the metal member 1 to be joined. Specifically, by setting a friction stir route on the joint (boundary line) between the metal member 1 to be joined and the first tab member 2, and moving the rotary tool F for temporary joining relatively along the route, Friction stirring is performed on the abutting portion J2. In the present embodiment, the friction stir is continuously performed from the start point s2 to the end point e2 of the first tab material joining step without causing the temporary joining rotary tool F to be detached on the way.

  In addition, when the rotary tool F for temporary joining is rotated to the right, there is a possibility that a fine cavity defect may be generated on the left side of the traveling direction of the temporary tool F for temporary joining. It is desirable to set the positions of the start point s2 and the end point e2 of the first tab material joining step so that the metal member 1 to be joined is located on the right side of the first tab material. 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 temporary bonding rotary tool F is rotated counterclockwise, a fine cavity defect may occur on the right side of the moving direction of the temporary bonding rotary tool F. It is desirable to set the positions of the start point and end point of the first tab material joining step so that the metal member 1 to be joined is located on the left side of the first tab material. Specifically, although illustration is omitted, a start point is provided at the position of the end point e2 when the temporary joining rotary tool F is rotated to the right, and the position of the start point s2 when the temporary joining rotary tool F is rotated to the right. An end point may be provided at.

  Note that, when the stirring pin F2 of the temporary joining rotary tool F enters the abutting portion J2, a force for separating the joined metal member 1 and the first tab member 2 acts, but the joined metal member 1 and the first tab Since the corners 2a and 2b (see FIG. 2) formed by the material 2 are temporarily joined by welding, no meshing occurs between the metal member 1 to be joined and the first tab material 2. .

(2-2) Temporary Joining Process When the temporary tool F for temporary joining reaches the end point e2 of the second tab material joining process, the friction stirrer is continuously performed up to the start point s1 of the temporary joining process without terminating the frictional stirring at the end point e2. And proceed to the temporary joining process as it is. That is, the frictional stirring is continued without detaching the temporary joining rotary tool F from the end point e2 of the first tab material joining process to the starting point s1 of the temporary joining process, and further, the temporary joining rotary tool F is detached at the start point s1. It moves to a temporary joining process without it. If it does in this way, the separation | elimination work of the rotary tool F for temporary joining in the end point e2 of a 1st tab material joining process becomes unnecessary, and also the insertion work of the rotational tool F for temporary joining in the start point s1 of a temporary joining process is unnecessary. Therefore, it becomes possible to improve the efficiency and speed of the preliminary joining work.

  In this embodiment, the friction stir route from the end point e2 of the first tab material joining process to the start point s1 of the temporary joining process is set to the first tab material 2, and the temporary joining rotary tool F is set to the first tab material joining process. The first tab member 2 is formed with a movement locus when moving from the end point e2 to the start point s1 of the temporary joining step. If it does in this way, since the cavity defect becomes difficult to generate | occur | produce in the to-be-joined metal member 1 in the process from the end point e2 of a 1st tab material joining process to the start point s1 of a temporary joining process, obtaining a high quality joined body. Is possible.

  In the temporary joining step, friction agitation is performed on the abutting portion J1 (see FIG. 6) of the metal member 1 to be joined. Specifically, a route for friction stirring is set on the joint (boundary line) of the metal member 1 to be joined, and the temporary tool rotation tool F is relatively moved along the route so that the total length of the abutting portion J1 is obtained. Friction stirring is continuously performed throughout. In the present embodiment, the friction stir is continuously performed from the start point s1 to the end point e1 of the temporary joining step without causing the temporary joining rotary tool F to be detached.

  When the temporary joining rotary tool F reaches the end point e1 of the temporary joining step, the friction stirrer is continuously performed to the start point s3 of the second tab member joining step without ending the friction stirring at the end point e1, and the second tab material is left as it is. Transition to the joining process. That is, the frictional stirring is continued without detaching the temporary joining rotary tool F from the end point e1 of the temporary joining process to the start point s3 of the second tab member joining process, and further, the temporary joining rotary tool F is detached at the start point s3. It shifts to the 2nd tab material joining process, without.

  In this embodiment, the friction stir route from the end point e1 of the temporary joining step to the start point s3 of the second tab member joining step is set to the second tab member 3, and the temporary tool rotary tool F is set to the end point e1 of the temporary joining step. The second tab member 3 is formed with a movement trajectory when moving from the starting point s3 of the second tab member joining step to the starting point s3. If it does in this way, since a cavity defect becomes difficult to generate | occur | produce in the to-be-joined metal member 1 in the process from the end point e1 of a temporary joining process to the start point s3 of a 2nd tab material joining process, obtaining a high quality joined body. Is possible.

(2-3) Second Tab Material Joining Step In the second tab material joining step, friction agitation is performed on the abutting portion J3 between the metal member 1 to be joined and the second tab material 3. Specifically, by setting a friction stir route on the joint (boundary line) between the metal member 1 to be joined and the second tab member 3, and relatively moving the rotary tool F for temporary joining along the route, Friction stirring is performed on the abutting portion J3. In the present embodiment, the friction stir is continuously performed from the start point s3 to the end point e3 of the second tab material joining step without causing the temporary joining rotary tool F to be detached on the way.

  Since the temporary joining rotary tool F is rotated to the right, the start point s3 and the end point e3 of the second tab member joining step are set so that the metal member 1 to be joined is positioned on the right side in the traveling direction of the temporary joining rotary tool F. Set the position of.

  Moreover, when the stirring pin F2 of the rotary tool F for temporary joining 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 Since the corners 3 a and 3 b (see FIG. 2) of the material 3 are temporarily joined by welding, no openings are generated between the metal member 1 to be joined and the second tab material 3.

When the rotary tool F for temporary joining reaches the end point e3 of the second tab material joining step, the friction stir is continuously performed to the end position E _P1 provided in the second tab material 3 without terminating the friction stirring at the end point e3. Do. In the present embodiment, the end position E _P1 is provided on the extension line of the seam (boundary line) that appears on the surface A side of the bonded metal member 1. Incidentally, the end position E _P1 is also a friction stirring start position S _M1 in a first main joining process described later.

When the temporary joining rotary tool F reaches the end position E _P1 , the temporary joining rotary tool F is raised while rotating to disengage the stirring pin F2 from the end position E _P1 .

As mentioned above, although the 1st tab material joining process, the temporary joining process, and the 2nd tab material joining process were explained,
The trajectory in each joining step is merely an example, and other forms may be used. Further, the first tab material joining step and the second tab material joining step may be omitted and only the temporary joining step may be performed.

(2-4) Pilot hole forming step Subsequently, a pilot hole forming step is executed. As shown in FIG. 4B, the pilot hole forming step is a step of forming the pilot hole P1 at the friction stirring start position in the first main joining step. In the pilot hole forming process according to the first preliminary process, the pilot hole P1 is formed in S _M1 set on the surface 32 of the first tab member 3.

  The pilot hole P1 is provided for the purpose of reducing the insertion resistance (press-fit resistance) of the stirring pin G2 of the rotary tool G for main joining, and in this embodiment, the stirring pin F2 (see FIG. 4 (see (a)) is formed by expanding the diameter of the punched hole H1 formed with a drill (not shown). If the punch hole H1 is used, the process of forming the pilot hole P1 can be simplified, and the working time can be shortened. 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 2nd tab material 3, there is no restriction | limiting in particular in the position of the pilot hole P1, You may form in the 1st tab material 2, 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 this embodiment, the case where the diameter of the hole H1 of the stirring pin F2 (see FIG. 4A) of the temporary joining rotary tool F is enlarged to be the pilot hole P1 is illustrated. greater than the minimum outer diameter Y ₃ of the stirring pin G2 of the maximum outer diameter X ₂ is rotating tool G for the bonding, and smaller than the maximum outer diameter Y ₂ of the maximum outer diameter X ₂ of the stirring pin F2 agitation pin G2 In the case of (Y ₃ <X ₂ <Y ₂ ), the hole H1 of the stirring pin F2 may be used as the pilot hole P1 as it is.

(3) 1st main joining process A 1st main joining process is a process of joining the butt | matching part J1 in the surface A side of the to-be-joined metal member 1 in earnest. In the first main joining step according to the present embodiment, the surface of the metal member 1 to be joined is used with respect to the abutting part J1 in a temporarily joined state using the main joining rotating tool G shown in FIG. Friction stirring is performed from the A side.

In a first main bonding step, as shown in FIG. 7 (a) ~ (c), a stirring pin G2 of the joining rotation tool G inserted (press-fitted) into the prepared hole P1 formed in the start position S _M1 Then, the inserted stirring pin G2 is moved to the end position E _M1 without being removed halfway. That is, in the first main joining process, the friction stirring is started from the pilot hole P1, and the friction stirring is continuously performed up to the end position E _M1 .

Here, at the time when the first preliminary process is completed, the friction stirrer provided with the temporary joining rotary tool F is located immediately above the end position E _P1 of the second tab member 3 (see FIG. 6). Therefore, when the start position of the first main joining step is set to _SM1 , the first main joining step can be performed without moving the friction stirrer provided with the main welding rotating tool G. Can be omitted.
In this embodiment, the second tab member 3 is provided with the friction stirring start position S _M1 and the first tab member 2 is provided with the end position E _M1 . However, the positions of the start position S _M1 and the end position E _M1 are the same. It is not intended to limit.

The first main joining process will be described in more detail with reference to FIGS.
First, as shown in FIG. 7A, the main welding rotary tool G is positioned immediately above the pilot hole P1 (start position S _M1 ), and then the main welding rotary tool G is rotated clockwise and lowered. The tip of the stirring pin G2 is inserted into the pilot hole P1. When the stirring pin G2 enters the pilot hole P1, the peripheral surface (side surface) of the stirring pin G2 comes into contact with the hole wall of the pilot hole P1, and the metal fluidizes plastically from the hole wall. In such a state, the agitation pin G2 is press-fitted while the plastic fluidized metal is pushed away by the peripheral surface of the agitation pin G2, so that the press-fitting resistance in the initial press-fitting stage can be reduced. In addition, since the stirring pin G2 comes into contact with the hole wall of the pilot hole P1 before the shoulder part G1 of the main rotating tool G comes into contact with the surface 32 of the second tab member 3, frictional heat is generated. It is possible to shorten the time to do. That is, it is possible to reduce the load on the friction stirrer, and in addition, it is possible to shorten the work time required for the main joining.

  When the entire stirring pin G2 enters the second tab member 3 and the entire lower end surface G11 of the shoulder portion G1 comes into contact with the surface 32 of the second tab member 3, as shown in FIG. The main rotating tool G is relatively moved toward one end of the abutting portion J1 of the metal member 1 to be joined while stirring, and further, the abutting portion J3 is traversed to enter the abutting portion J1. When the rotary tool G for main joining is moved, the metal around the stirring pin G2 is plastically fluidized at the same time, and at the position away from the stirring pin G2, the plastic fluidized metal is hardened again and plasticized. A region (hereinafter referred to as “surface-side plasticized region W1”) is formed.

  The moving speed (feeding speed) of the main rotating tool G for welding is set according to the size and shape of the agitating pin G2, the material and thickness of the metal member 1 to be joined by friction stirring, In many cases, it is set within a range of 30 to 300 (mm / min).

  If the amount of heat input to the metal member 1 to be bonded is likely to be excessive, it is desirable to cool the surface of the main rotating tool G by supplying water from the surface A side. In addition, when cooling water enters between the first metal member 1a and the second metal member 1b, there is a possibility that an oxide film may be generated on the joining surfaces (end surfaces 11a and 11b, see FIG. 2B). In the embodiment, since the joint between the bonded metal members 1 is closed by executing the temporary bonding process, it is difficult for the cooling water to enter between the bonded metal members 1 and there is no possibility of deteriorating the quality of the bonded portion.

At the abutting portion J1 of the metal member 1 to be joined, a route of friction stirring is set on the joint of the metal member 1 to be joined (on the movement trajectory in the temporary joining process), and the main rotating tool G is relatively moved along the route. By moving, friction stir is performed continuously from one end to the other end of the abutting portion J1. When the main rotating tool G is relatively moved to the other end of the abutting portion J1, the abutting portion J2 is moved across the abutting portion J2 while performing frictional stirring, and is relatively moved toward the end position E _M1 as it is.

In the present embodiment, since the friction stirring start position S _M1 is set on the extension 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, The route of friction stirring in the main joining process can be made straight. If the route of friction stirring is made straight, the moving distance of the main welding rotary tool G can be minimized, so that the first main welding process can be efficiently performed. The wear amount of the tool G can be reduced.

When the main welding rotary tool G reaches the end position E _M1 , as shown in FIG. 7C, the main welding rotary tool G is raised while rotating and the stirring pin G <b> 2 is moved to the end position E _M1 (FIG. 7). (See (b)). Note that if the stirring pin G2 is separated upward at the end position E _M1 , a punch hole Q1 having substantially the same shape as the stirring pin G2 is inevitably formed, but in this embodiment, it is left as it is.

The rotational speed of the main welding rotary tool G when the stirring pin G2 of the main welding rotary tool G is detached from the end position _EM1 (the rotational speed at the time of separation) may be higher than the rotational speed at the time of movement. desirable. In this case, the separation resistance of the stirring pin G2 becomes smaller than when the rotational speed at the time of separation is the same as the rotational speed at the time of movement, so that the work of removing the stirring pin G2 at the end position E _M1 can be performed quickly. Can be done.

  In this embodiment, the first preliminary process is performed before the first main bonding process, but the first preliminary process is omitted and the first main process is performed immediately after the first preliminary process. A joining process may be performed.

(4) Second preparation step The second preparation step is a preparation step that is performed prior to the second preliminary step. In this embodiment, the to-be-joined member installation process which installs again in the friction stirring apparatus which is not shown in figure with the back surface B side of the to-be-joined metal member 1 facing upwards is comprised.

(4-1) To-be-joined member installation process In the to-be-joined member installation process, after releasing the restraint of the to-be-joined metal member 1 that has finished the first main joining process, the front and back of the to-be-joined metal member 1 are reversed, Place the back B side up and place it again on the frame of the friction stirrer. In this embodiment, the metal member 1 to be bonded is rotated halfway around the longitudinal axis shown in FIG. 1 so that the front and back of the metal member 1 to be bonded are reversed.
Here, (a) of FIG. 8 is sectional drawing which faces the 1st metal member 1a side from the abutting part J1, after the to-be-joined member installation process of the 2nd preparation process which concerns on this embodiment. As shown to (a) of FIG. 8, in the to-be-joined member installation process, when the upper surface of the to-be-joined metal member 1 becomes the back surface B and the 1st metal member 1a is faced from the abutting part J1 side, to-be-joined metal member The second tab material 3 is located on the left side of 1 and the first tab material 2 is located on the right side.
Note that, depending on the friction stirrer, the front and back surfaces may be rotated without releasing the restraint of the bonded metal member 1.
(5) Second Preliminary Step The second preliminary step is a step that is performed prior to the second main joining step, and on the back surface B side, the abutting portion J3 between the metal member 1 to be joined and the second tab member 3. (5-1) the second tab material joining step, and the joining portion J1 of the joined metal member 1 are temporarily joined (5-2) the temporary joining step, the joined metal member 1 and the first tab material 2 (5-3) a first tab material joining step, and a pilot hole is formed at a friction stirring start position in the second main joining step (5-4) a pilot hole forming step. It has. In the (5-1) second tab material joining step, the (5-2) temporary joining step, and the (5-3) first tab material joining step, the temporary joining rotary tool F is used.

(5-1) Second tab material joining step, (5-2) Temporary joining step and (5-3) First tab material joining step (5-1) Second tab material joining step, (5-2) Temporary The joining step and the (5-3) first tab material joining step are (2-3) the second tab material joining step, (2-2) the temporary joining step and (2-1 ) It is a process substantially equivalent to the first tab material joining process. As shown in FIG. 8B, one temporary joining rotary tool F is moved so as to form a one-stroke writing movement trajectory (bead), and continuously in the order of the abutting portions J3, J1, and J2. Friction stirring is performed. That is, the stirring pin F2 (see (a) of FIG. 4) of the temporary welding rotary tool F inserted at the friction stirring start position _SP2 is moved to the end position _EP2 without being removed halfway (5-1 ) The second tab material joining step, (5-2) the temporary joining step, and (5-3) the first tab material joining step are successively executed. Note that the end position E _P2 is a start position S _M2 of a second main joining process to be performed later.

Here, in the first preliminary step, as shown in FIG. 6, from the first tab member 2 side, (2-1) the first tab member joining step, (2-2) the temporary joining step, and (2-3 ) The second tab material joining step was sequentially performed. On the other hand, in the second preliminary process, when facing the first metal member 1a side from the abutting portion J1, the second tab member 3 is located on the left side of the metal member 1 to be joined and the first main joining process is finished. At this point, since the friction stirrer provided with the main rotating tool G for welding is located above the second tab member 3, the second tab member 3 side (5-1) the second tab member joining step ( 5-2) The temporary joining step and (5-3) the first tab material joining step are sequentially performed. In this case, since the moving distance of the friction stirrer provided with the temporary joining rotary tool F is small, work can be saved.
The detailed description of the (5-1) second tab material joining step, (5-2) temporary joining step, and (5-3) first tab material joining step is substantially the same as the first preliminary step. Omitted.

(5-4) prepared hole forming step the prepared hole forming step, as shown in FIG. 9 (a) is the step of forming a prepared hole P2 in the second start position S _M2 of the friction stir in the welding process . That is, the pilot hole forming step is a step of forming the pilot hole P2 at a position where the stirring pin G2 of the main rotating tool G is to be inserted. Thereby, the insertion resistance (press-fit resistance) of the stirring pin G2 of the rotating tool G for main joining can be reduced.
Since the (5-4) pilot hole forming step is substantially the same as the (2-4) pilot hole forming step according to the first preliminary process, detailed description thereof is omitted.

(6) Second Main Joining Step The second main joining step is a step of fully joining the abutting portion J1 on the back surface B side of the metal member 1 to be joined. In the second main joining step according to the present embodiment, the main joining rotating tool G is used, and friction agitation is performed from the back surface B side of the joined metal member 1 to the abutting portion J1 in a temporarily joined state.

In the second main joining step, as shown in FIGS. 9A and 9B, the stirring pin G2 of the rotary tool G for main joining is inserted into _SM2 set on the back surface 23 of the first tab member 2. (Press-fitting), and the inserted stirring pin G2 is moved to the end position E _M2 without being removed halfway. In the second main joining step, friction agitation is started from the pilot hole P2, and friction agitation is continuously performed up to the end position _EM2 . When the rotary tool G for main joining is moved, the metal around the stirring pin G2 is plastically fluidized at the same time, and at the position away from the stirring pin G2, the plastic fluidized metal is hardened again and plasticized. A region (hereinafter referred to as “back side plasticizing region W2”) is formed.

Here, when the second preliminary process is completed, the friction stirrer provided with the temporary joining rotary tool F is directly above the end position _EP2 of the first tab member 2 (see FIG. 8B). due to the position, setting the start position S _M2 of the second main bonding step above the first tab member 2, the first aspect of the present without moving the friction stir apparatus having a main bonding rotation tool G A joining process can be performed and a work can be omitted.
Note that the second main bonding step is substantially the same as the first main bonding step, and thus detailed description thereof is omitted. In the present embodiment, the second preliminary process is performed, but the second preliminary process may be omitted and the second main bonding process may be performed immediately after the first main bonding process.

(7) Tab Material Cutting Process The tab material cutting process is a process of cutting the first tab material 2 and the second tab material 3 from the bonded metal member 1. In this embodiment, the to-be-joined metal member 1 that has finished the second main joining step is once removed from the frame of the friction stirrer, and the first tab member 2 and the butt portion J2 and J3 are used along the abutting portions J2 and J3 using a cutting tool (not shown). The second tab member 3 is cut off.

  FIG. 10 is a perspective view showing the bonded metal member 1 after performing the tab material cutting step. As shown in FIG. 10, the front surface side plasticized region W1 and the back surface side plasticized region W2 are continuously formed from the first side surface C side to the second side surface D side. On the other hand, a fine unplasticized region j that is continuous from the first side surface C side to the second side surface D side is formed between the front surface side plasticized region W1 and the back surface side plasticized region W2. Yes.

Here, in the front side plasticizing region W1 and the back side plasticizing region W2, the traveling direction of the main rotating tool G (see arrows V ₁ and V ₂ ) is on the left side, that is, the second metal member 1b It is assumed that tunnel-like cavity defects R ₁ and R ₂ are generated from the side C side to the second side D side. The tunnel-like cavity defects R ₁ and R ₂ are tunnel-like cavity defects that are formed when the friction stir welding is performed and the gap between the abutting portions J1 is filled or burrs are generated and the metal is insufficient. .

Further, as shown in FIG. 10, both ends of the surface side plasticized region W1 and the rear surface side plasticized region W2, it is assumed that the oxide film Z ₁ to Z ₄ are involved. The oxide films Z _{1 to} Z ₄ are formed by winding the oxide films formed on the first side surface C, the second side surface D, the first tab material 2 and the second tab material 3 inside the metal member 1 to be joined. Is. For example, oxide film Z ₁ is, since the present joining rotation tool G is rotated clockwise, by involving the second side D and the oxide film formed on the first tab member 2, on the back side plasticized region W2 It tends to be formed on the second metal member 1b side.

(8) Concave Groove Forming Step The concavity groove forming step is a step of forming the concave groove K along the abutting portion J1 on the first side surface C and the second side surface D as shown in FIG. The concave groove K is a concave portion for arranging the joint member U in the joint member arranging step described later. In this embodiment, the concave groove K is continuously formed from the back surface B to the front surface A with a constant width k ₁ and depth k ₂ using a known end mill or the like.

By providing the concave groove K, the joint member U can be disposed and the oxide films Z _{1 to} Z ₄ (see FIG. 10) can be removed when performing the joint member joining step described later. That is, the width k ₁ and the depth k ₂ of the concave groove K may be appropriately set according to the size (range) of the oxide films Z _{1 to} Z ₄ . In this embodiment, the concave groove K is formed in a rectangular shape in sectional view, but is not limited to this, and may have another shape. The cross-sectional shape of the concave groove K is preferably substantially the same as the cross-sectional shape of the joint member U so that the joint member U can be fitted with almost no gap.

(9) First Weld Repair Process FIG. 12 is a plan view on the first side face C side after the concave groove forming process. The first welding repair process is a process of repairing the unplasticized region j exposed on the bottom surface kb of the groove K by welding as shown in FIG. Further, when the tunnel-like cavity defects R ₁ and R ₂ are exposed on the bottom surface kb as in the present embodiment, it is preferable to repair the tunnel-like cavity defects.

As described above, in the present embodiment, on the bottom surface kb of the groove K, the unplasticized region j is exposed between the front surface side plasticized region W1 and the back surface side plasticized region W2. Further, the bottom surface kb, tunnel-like void defects R ₁ on the surface side plasticized region W1 is a tunnel-like void defects R ₂ on the back side plasticized region W2 are exposed, respectively.
Therefore, to seal the gap by welding metal T ₁ performs welding over the entire length of the non-plasticized region j. Further, the tunnel-shaped cavity defects R ₁ and R ₂ are welded, and the gap is sealed with the weld metal T ₂ . As described above, the airtightness and watertightness between the first side face C and the second side face D can be further increased by preliminarily filling the gap (gap) exposed on the bottom face kb.

  The type of welding in the first welding repair process is not limited. For example, after performing build-up welding by MIG welding, TIG welding, or the like, the build-up portion protruding from the bottom surface kb of the groove K is cut off to obtain the bottom surface kb. Is preferably smoothed. By smoothing the bottom surface kb, the gap between the joint member U and the bottom surface kb of the groove K can be reduced when a joint member U described later is disposed in the groove K.

  In addition, since there is a possibility that a cavity defect that is not exposed to the bottom surface kb is formed inside the front side plasticization region W1 and the back side plasticization region W2, the front side plasticization region W1 and the back side plasticization region Welding repair may be performed on the entire surface of W2 in advance.

(10) Third Preparation Step The third preparation step is a step performed prior to the first joint member joining step. In the present embodiment, the third preparatory step is the first joint member disposing step (10-1) in which the first joint member U (U1) is disposed in the concave groove K, and the first joint member disposing on both side surfaces of the metal member 1 to be joined. The tab material 2 and the second tab material 3 are arranged (10-2), and the first tab material 2 and the second tab material 3 are temporarily joined to the metal member 1 by welding (10- 3) A temporary welding process and a metal member 1 to be bonded on which the tab material is arranged are installed on a frame of the friction stirrer (10-4) a metal member installation process to be bonded.

(10-1) First Joint Member Placement Step The first joint member placement step is a step of placing the first joint member U1 in the concave groove K formed in the first side surface C, as shown in FIGS. It is. Hereinafter, the configuration of the first joint member U1 will be described in detail.

As shown in FIG. 13, the first joint member U <b> 1 is a plate-like member having a rectangular shape in cross section, and both end surfaces in the longitudinal direction are formed to be flush with the front surface A and the back surface B. As shown in (a) of FIG. 14, the width u ₁ of the first coupling member U1 is substantially equally formed with the width k ₁ of the groove K, thickness u ₂ of the first coupling member U1 is concave It is substantially equally formed and the thickness k ₂ of the grooves K. Further, the side surfaces uc and ud of the first joint member U1 are arranged to face the wall surfaces kc and kd of the concave groove K.

  That is, as shown in FIGS. 14A and 14B, the upper surface ua of the first joint member U1 is formed flush with the first side surface C, and is recessed with the side surface uc of the first joint member U1. A first abutting portion J4 is formed by the wall surface kc of the groove K. A second abutting portion J5 is formed by the side surface ud of the first joint member U1 and the wall surface kd of the groove K. That is, the first abutting portion J4 refers to a portion formed by the first joint member U1 and the first metal member 1a. The second abutting portion J5 refers to a portion formed by the first joint member U1 and the second metal member 1b. Further, a boundary portion J6 is formed by the lower surface ub of the first joint member U1 and the bottom surface kb of the concave groove K. Moreover, let the part containing the centerline of a longitudinal direction be the center part J7 in the upper surface ua of the 1st coupling member U1.

  In addition, in this embodiment, although the 1st coupling member U1 consists of a metal member equivalent to the to-be-joined metal member 1, it is not limited to this, For example, aluminum, aluminum alloy, copper, copper alloy, titanium Further, a metal material that can be frictionally stirred such as titanium alloy, magnesium, and magnesium alloy may be used.

(10-2) Tab Material Arrangement Step In the tab material arrangement step, as shown in FIG. 15A, the first tab material 2 is arranged along the surface-side plasticized region W1 on the surface A, and The contact surface 21 is brought into contact with the surface A. Furthermore, the 2nd tab material 3 is arrange | positioned along the back surface plasticization area | region W2 in the back surface B, and the contact surface 31 is made to contact | abut to the back surface B. FIG.
Although not specifically illustrated, the surfaces of the first tab member 2 and the second tab member 3 and the first side surface C of the metal member 1 to be joined are formed flush with each other. Moreover, the back surface of the 1st tab material 2 and the 2nd tab material 3 and the 2nd side surface D of the to-be-joined metal member 1 are formed flush | planar. By attaching the first tab member 2 and the second tab member 3 to the metal member 1 to be joined, the starting position (insertion position) of the rotary tool can be easily set, and the friction stir welding can be performed quickly. Can do.

(10-3) Temporary Welding Process In the temporary welding process, as shown in FIG. 15 (a), the corners 2a and 2b formed by the metal member 1 and the first tab material 2 are welded. The metal member 1 to be bonded and the first tab material 2 are temporarily bonded. Furthermore, the corners 3 a and 3 b formed by the metal member 1 and the second tab material 3 are welded to temporarily bond the metal member 1 and the second tab material 3 to each other.

(10-4) To-be-joined metal member installation process In the to-be-joined metal member installation process, as shown to (a) of FIG. It is installed on a frame of a friction stirrer (not shown) so that the material 2 is located on the left side.

  In the third preparation step, the first embodiment is performed as described above. However, for example, the first joint member arrangement step may be performed after the metal member installation step.

(11) First joint member joining step The first joint member joining step is a step of performing friction stir welding on the first joint member U1 disposed on the first side face C, as shown in FIGS. . In this embodiment, the first joint member joining step performs friction stir welding along the first abutting portion J4 (11-1) The first abutting portion joining step and the friction stir welding along the center portion J7. (11-2) center part joining step to be performed, and (11-3) second butt part joining step to perform friction stir welding along the second butt part J5.

  In the first joint member joining step, the friction stir welding is performed in a one-stroke manner without removing the rotary tool from the start position to the end position. In the first joint member joining step, a temporary joining rotary tool F having a relatively small turn is used. In the present embodiment, the temporary stirring rotary tool F is rotated clockwise to perform friction stir welding.

(11-1) the first butting portion joining step first butting portion bonding process is continuous until the turning point f ₂ along from the start position S _M3 formed in the first tab member 2 of the surface of the first butting portion J4 Thus, friction stir welding is performed. After the start position S _M3 presses the rotary tool F for temporary joining, the rotating tool F for temporary joining is relatively moved toward the starting point f ₁ of the first butting portion joining step. Then, as it traverses the butting portion J8 without leaving at the start f _1, it is moved to the turning point f _2. The plasticized region formed in the first butting portion joining step, the first side surface plasticized region w _1.

Configuration Here, as shown in (b) of FIG. 15, as the depth wa of the first side surface plasticized region _{w 1,} and the thickness _{u 2} of the first coupling member U1, a wa> _{u 2} It is preferable to do this. Thereby, friction stir welding can be performed over the full length of the thickness direction of the 1st butt | matching part J4.

Incidentally, buried depth p of the temporary joining rotation tool F is the length L ₂ of the stirring pin F2, (distance from the first side surface C to the lower surface of the shoulder portion F1) pressing amount q of the rotary tool F for temporary joining And p = L ₂ + q. For example, if the relationship between the embedding depth p and the thickness u ₂ of the first joint member U 1 is set so that p ≧ u ₂ , the friction stir welding can be performed more reliably.

Further, as shown in (b) of FIG. 15, the outer diameter _{X 1} of the shoulder portion F1 of the rotary tool F for temporary bonding, the relationship between the width _{u 1} of the first coupling member U1 is, 3 × _X 1> u It is preferably set to be ₁ . By setting in this way, the entire upper surface ua of the first joint member U1 can be friction stir welded.

Turning point f _2, in this embodiment, set to a first coupling member U1. That is, the turning point f _2, as well located on the back side plasticized region W2 in plan view, the distance d ₁ from the back side B to the turning point f _2, the outer shoulder portion F1 of the rotary tool F for temporary joining relationship between the diameter _{X 1} (see (a) in FIG. 4) is _preferably set to a position where the X _{1/2 <d} 1. The turning point f ₂ By setting in this manner, it is possible to rotate the tool F for temporary joining is not expose the rear surface B. Thereby, since the oxide film currently formed in the back surface B is not wound in the 1st joint member U1 side, the to-be-joined metal member 1 with high airtightness and water-tightness can be formed.

Note that (if the pressing amount q = 0) the rotary tool F for temporary bonding If not pressed below the first side face C, the set position of the turning point _{f 2 is, X 2/2 <d 1} (X 2 = the upper end diameter of the stirring pin F ₂ may be set so that (in FIGS. 4 (a) see)).
Further, in the present embodiment is provided with the turning point f ₂ to be joined metal member 1 is not limited thereto, may be provided on the second tab member 3.

(11-2) central bonding process central bonding step is for performing friction stir welding continuously from the starting point f ₃ of the central portion joining process until the turning point f ₄ of the central portion joining process along a central portion J7 is there. That is, after completion of the first butting portion joining step, substantially to move parallel to the rear surface B without leaving the rotary tool F for temporary joining, performing friction stir welding from turning point f ₂ to the start point f _3. Then, when it reaches the starting point f _3, performing friction stir welding along a central portion J7 (butting portion J1). Thereby, friction stir welding can be performed in the central portion of the first joint member U1.

Further, as shown in FIG. 15B, the depth wa of the first side surface plasticized region w ₂ formed in the center part joining step is larger than the thickness u ₂ of the first joint member U. Set to. Furthermore, the starting point f ₃ of the central portion joining step, on the back side plasticized region W2 in plan view, the folding point f _4, is set to be viewed surface plasticized region W1. Thereby, since friction stir welding can be performed over the full length of the unplasticized area | region j, a clearance gap can be sealed more reliably.

In the present embodiment, the turning point f ₄ of the central portion joining step is set to the first joint member U1. That is, the turning point f ₄ serves to set the surface plasticized region W1 in plan view, the distance d ₂ from the surface A to the turning point f _4, the outer shoulder portion F1 of the rotary tool F for temporary joining diameter _{X 1} relationship between (in FIGS. 4 (a) refer) is preferably set such that _{X 1/2 <d} 2. The turning point f ₄ By setting like this, the rotational tool F for temporary joining can be prevented applied to the surface A. Thereby, since the oxide film currently formed in the surface A is not wound in the 1st joint member U1 side, the to-be-joined metal member 1 with high airtightness and water-tightness can be formed.

(11-3) Second butting portion joining step the second butting portion bonding step, to perform friction stir welding continuously to the end position E _M3 along the starting point f ₅ of the second butting portion second butting portion J5 It is. That is, after the end of the central portion joining process, and performs friction stir welding from the surface A and the turn-back point f ₄ substantially in parallel to the movement without disengaging the rotary tool F for temporarily joined to the starting point f _5. Performing friction stir welding along a second butting portion J5 when it reaches the starting point f _5. Then, upon reaching the end point f ₆ of the second butting portion bonding step, as it traverses the butting portion J9 is moved to the end position E _M3 and, disengaging the rotating tool F for temporary bonding of the second tab member 3.

FIG as shown in (b) of 15, the depth wa of the first side surface plasticized region w ₃ which is formed in the second butting portion bonding process, so as to be larger than the thickness u ₂ of the first coupling member Is formed. Thereby, friction stir welding can be performed over the full length of the thickness direction of the 2nd butt | matching part J5.

When the first joint member joining step described above is viewed in plan, a bead as shown in FIG. 16 is formed. That is, the first coupling member U1 is covered by the first side face side plasticized region w ₁ to w ₃ while leaving a portion of the ends of the first coupling member U1. Further, as shown in (b) of FIG. 15, the total cross section of the first coupling member U1 is friction stir at first side surface plasticized region w ₁ to w _3.

In the first joint member joining step, the boundary J6 formed by the bottom surface kb of the concave groove K and the lower surface ub of the first joint member U is friction stir welded over the entire surface as in the present embodiment. Is preferred. Accordingly, the bottom surface kb of the groove K is frictionally stirred by the front surface side plasticized region W1, the back surface side plasticized region W2, and the first side surface side plasticized regions w _{1 to} w ₃ , so that the abutting portion J1 is formed without a gap. It can be surely sealed.

Incidentally, as shown in (b) of FIG. 14, the width k ₁ of the groove K, the width n of the back-side plasticized region W2, preferably formed such that k 1 _<n. Accordingly, it is possible to set small width u ₁ of the first coupling member U1, it is possible to enhance the working efficiency.
That is, in this embodiment, the friction stir welding is performed in three ways (one reciprocation half) from the relationship between the width u ₁ of the first joint member U ₁ and the outer diameter X ₁ of the shoulder portion F ₁ of the temporary joining rotary tool F. However, the present invention is not limited to this. When the lengths of the width u ₁ of the first joint member U and the outer diameter x ₁ of the shoulder portion are close to each other, the number may be one or two.
On the other hand, when the difference in length between the width u ₁ of the first joint member U and the outer diameter x ₁ of the shoulder portion is increased, the number may be four or more. Moreover, it does not necessarily need to be a linear bead, and friction stir welding may be performed zigzag.

(12) Fourth Preparation Step The fourth preparation step is a step performed prior to the second joint member joining step. In the fourth embodiment, in the present embodiment, the second joint member U (U2) is disposed in the groove K (12-1) and the second joint member U2 is disposed and the second joint member U2 is disposed. The joining metal member 1 is installed in the friction stirrer (12-2) The joined metal member installing step is provided. Since the fourth preparation process is substantially the same as the third preparation process, it will be briefly described.

(12-1) Second Joint Member Arrangement Step First, after the first joint member joining step is finished, the metal member 1 to be joined fixed to the frame of the friction stirrer (not shown) is removed, and the second side D side is directed upward. The second joint member U2 is disposed in the concave groove K formed in the second side face D.

(12-2) Joined metal member installation step As shown in FIG. 17, when the joined metal member 1 is viewed in plan, the second tab material 3 is arranged on the left side and the first tab material 2 on the right side. The metal member 1 to be bonded is placed in a friction stirrer (not shown) so that is disposed.
In addition, after performing the (12-2) to-be-joined metal member installation process, you may perform the (12-1) 2nd joint member arrangement | positioning process.

(13) Second joint member joining step The second joint member joining step is a step of performing friction stir welding on the second joint member U2 arranged on the second side face D as shown in FIG. In this embodiment, the second joint member joining step performs friction stir welding on the second butted portion J5 ′ (13-1) and performs friction stir welding on the second butting portion joining step and the central portion J7 ′ ( 13-2) A center part joining process and a friction stir welding to the first abutting part J4 ′ are performed (13-3) a first abutting part joining process.

As shown in FIG. 17, the second joint member joining step is temporarily joined from the start position S _M4 set on the surface of the first tab member 2 to the end position E _M4 set on the surface of the second tab member 3. Friction stir welding is performed in the manner of a single stroke without detaching the rotary tool F.
When the first joint member joining step is completed, a friction stirrer (not shown) is arranged on the right side of the metal member 1 to be joined when the metal member 1 to be joined is viewed in plan. Therefore, the start position S _M4 of the second coupling member bonding step is preferably set to the surface of the second tab member 3. Thereby, the movement of the friction stirrer can be omitted and work efficiency can be improved.

(13-1) Second abutting portion joining step, (13-2) Center portion joining step, and (13-3) First abutting portion joining step are respectively described in (11-3) Second abutting portion joining step, Since (11-2) the center part joining step and (11-1) the first butting part joining step are friction-stirred from the opposite side, detailed description is omitted. Incidentally, the second joint member joining step each second side surface plasticized region w ₁ the plasticized region formed by 'to w _3'.

(14) Tab material cutting step The tab material cutting step is a step of cutting the first tab material 2 and the second tab material 3 from the bonded metal member 1. In this embodiment, the to-be-joined metal member 1 which finished the 2nd joint member joining process is removed from the mount of a friction stirrer, and the butt | matching part of the 1st tab material 2 and the to-be-joined metal member 1 using the cutting tool which is not shown in figure. The first tab member 2 and the second tab member 3 are cut along the abutting portion J9 between the J8 and the second tab member 3 and the metal member 1 to be joined.

(14) Second Weld Repair Process The second weld repair process includes the first side member plasticizing regions w ₁ and w ₃ and the second side member plasticity formed in the first joint member joining step and the second joint member joining step. This is a step of repairing the tunnel-like cavity defect and oxide film formed in the formation regions w ₁ ′ and w ₃ ′ by welding.
That is, as shown in FIG. 18, there is a consideration that a tunnel-like cavity defect r ₁ continuous from the surface A to the back surface B side is formed on the surface A of the first side surface plasticized region w ₁ . Therefore, by performing the welding in a tunnel-like void defects r _1, can be divided between the surface A and the back surface B seals the tunnel-like void defects r ₁ in the weld metal T _3.

Further, the first side surface plasticized region w ₁ according to the surface A, there is Omonbakari oxide film z ₁ is formed by the provisional joining rotary tool F traverses the surface A. Therefore, by performing the welding oxide film z _1, to seal the gap of the oxide film z ₁ in the weld metal T _4.
In this way, by joining the tunnel-like cavity defect r ₁ and the oxide film z ₁ exposed on the surface A by welding with the first side surface plasticizing region w ₁ , the metal to be joined having higher airtightness and watertightness. The member 1 can be formed. Incidentally, the first side surface side plasticized region w _3, the second side face side plasticized region w ₁ ', the second side face side plasticized region w _3' even, possibly tunnel-like void defects or oxide film is formed is there. In such a case, the second welding repair process is performed in the same manner as in the _first side plasticization region w1.

  Furthermore, as shown in FIG. 18, the gap between the abutting portion J5 and the boundary portion J6 may be sealed by welding the abutting portion J5 and the boundary portion J6 in the first joint member U1. Thereby, the to-be-joined metal member 1 with much higher airtightness and watertightness can be formed.

As described above, according to the bonding method according to the present embodiment, the concave groove K is formed in the first side surface C and the second side surface D of the metal member 1 to be bonded, so that the side surface of the metal member 1 to be bonded is formed. The oxide films Z _{1 to} Z ₄ that may be involved can be removed. Further, the joint member U is disposed in the unplasticized region j exposed to the groove K formed in the first side surface C and the second side surface D, and the cavity defects R ₁ and R ₂ , and the joint member U and the groove K are disposed. the first butting portion J4 and, by friction stir welding the central portion J7 and the second butting portion J5, can be sealed non-plasticized region j, the void defects R ₁ and R _2. Thereby, the airtightness between both side surfaces of the to-be-joined metal member 1 and watertightness can be improved, and a quality product can be manufactured.

In the present embodiment, since both end faces of the joint member U and the front surface A and the back surface B are flush with each other, the tunnel-like cavity defects R ₁ and R ₂ exposed on the bottom surface kb of the concave groove K are surely obtained. While being able to divide, the surface A and the back surface B of the to-be-joined metal member 1 can be formed flat. Further, by performing the friction stir welding through the joint member U, the joining strength of the abutting portion J1 can be increased.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to an above-described form, It can change suitably. For example, in the present embodiment, the joint member joining step is performed on both side surfaces of the first side surface C and the second side surface D. However, the joint member joining step may be performed only on one of the side surfaces. Further, the process order is merely an example, and the joining may be performed by changing the order as appropriate.

For example, as shown in FIG. 19, depending on the relationship between the width u ₁ of the joint member U ′ and the shoulder portion F 1 outer diameter X ₁ of the temporary joining rotary tool F, the first abutting portion J 4 and the second abutting portion J 5. Friction stir welding may be performed only in two ways. Thereby, since a process can be reduced, it can join more rapidly.

  Moreover, in this embodiment, although the 1st tab material 2 and the 2nd tab material 3 were used, you may perform friction stir welding, without using these contact members.

It is the figure which showed the joining method which concerns on this embodiment, Comprising: (a) is a perspective view, (b) is an expansion perspective view in the N section of (a). It is the figure which showed the (1) 1st preparation process which concerns on this embodiment, Comprising: (a) is a perspective view, (b) is a top view. (1) It is the figure which showed the 1st preparatory process concerning this embodiment, (a) is II sectional view taken on the line of (b) of FIG. 2, (b) is (b) of FIG. It is II-II sectional view taken on the line. It is the figure which showed the rotary tool which concerns on this embodiment, Comprising: (a) is a side view of the rotary tool for temporary joining, (b) is a side view of the rotary tool for final joining. It is the figure which showed the use condition of the rotary tool for temporary joining which concerns on this embodiment, Comprising: (a) is the figure which made the rotary tool for temporary joining contact the 2nd tab material, (b) It is the figure which pushed the rotary tool for temporary joining into the 2nd tab material. It is the top view which showed the 1st tab material joining process of the 1st preliminary process which concerns on this embodiment, a temporary joining process, and the 2nd tab material joining process. It is sectional drawing which showed the 1st main joining process which concerns on this embodiment in the III-III arrow direction of FIG. 6, Comprising: (a) is a starting position part, (b) is an intermediate part, (c). These are figures which showed the friction stir welding of the end position part. (A) is sectional drawing which faces the 1st metal member 1a side from the abutting part J1 after the 2nd preparatory process which concerns on this embodiment. (B) is the top view which showed the 2nd tab material joining process of the 2nd preparatory process which concerns on this embodiment, a temporary joining process, and a 1st tab material joining process. FIG. 8B is a cross-sectional view taken along the line IV-IV in FIG. 8B illustrating the second main joining process according to the present embodiment, where FIG. 8A is a start position portion, and FIG. It is the figure which showed joining. It is the perspective view which showed the to-be-joined metal member after the tab material cutting process which concerns on this embodiment. It is the perspective view which showed the ditch | groove formation process which concerns on this embodiment. FIG. 4 is a diagram showing a first welding repair process according to the present embodiment, and is a plan view of a first side surface C. It is the perspective view which showed the 1st joint member arrangement | positioning process which concerns on this embodiment. It is the side view which looked at the 1st joint member arrangement | positioning process which concerns on this embodiment from the 1st side C side, Comprising: (a) is before arrangement | positioning, (b) shows after arrangement | positioning. It is the figure which showed the 1st joint member joining process which concerns on this embodiment, Comprising: (a) is a top view, (b) is the VI-VI sectional view taken on the line of (a). It is the top view which showed the 1st joint member joining process which concerns on this embodiment. It is the top view which showed the 2nd joint member joining process which concerns on this embodiment. It is the figure which showed the 2nd welding repair process which concerns on this embodiment, Comprising: It is an expansion perspective view of N part of FIG. It is the figure which showed the modification which concerns on this embodiment, Comprising: It is sectional drawing which showed the joint member joining process. 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 To-be-joined metal member 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 Temporary joining rotation tool G Main rotation tool j Unplasticized region J1 to J3 Abutting portion J4 First abutting portion J5 Second abutting portion K concave groove ka concave groove width kb concave groove bottom surface P pilot hole R ₁ , R ₂ tunnel-like cavity defect T weld metal U joint member u ₂ thickness W1 surface plasticized region W2 backside plasticized region of the joint member w ₁ to w ₃ side surface plasticized region Z ₁ to Z ₄ oxide film

Claims (8)

A joining method in which a frictional stirring is performed by moving a rotating tool with respect to a metal member to be joined formed by abutting a first metal member and a second metal member,
A first main joining step of performing frictional stirring on the surface of the metal member to be joined with respect to the abutting portion between the first metal member and the second metal member;
A second main joining step of performing frictional stirring on the back surface of the metal member to be joined with respect to the abutting portion;
A concave groove forming step of forming a concave groove along the abutting portion according to the side surface of the metal member to be bonded;
A joint member arranging step of arranging a joint member in the concave groove;
A joint member joining step of performing friction stirring on the abutting portion between the concave groove and the joint member. The joint member joining step includes
In the concave groove, an unplasticized region exposed between the front side plasticized region formed in the first main joining step and the back side plasticized region formed in the second main joining step. The joining method according to claim 1, wherein sealing is performed.   The joining method according to claim 1 or 2, wherein both end faces of the joint member are flush with the front surface and the back surface of the metal member to be joined.   The joining method according to any one of claims 1 to 3, wherein a depth of the side surface plasticizing region formed in the joint member joining step is larger than a thickness of the joint member.   The first welding repairing step of sealing at least one of the cavity defect exposed on the bottom surface of the concave groove and the unplasticized region with a weld metal after the concave groove forming step. Item 5. The joining method according to any one of Items 4 to 5.   After the joint member joining step, a second welding repair step of sealing at least one of a cavity defect exposed on the front surface and the back surface by the joint member joining step and an oxide film engulfed by the joint member joining step with a weld metal. The joining method according to claim 1, wherein the joining method is included.   The width | variety of the said ditch | groove is a joining method as described in any one of the Claims 1 thru | or 6 characterized by being smaller than the width | variety of the said surface side plasticization area | region and the said back surface side plasticization area | region. The joining method according to any one of claims 1 to 7, wherein a pilot hole is formed in advance at a position where the rotating tool is to be inserted.

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