JP5092561B2 - Joining method - Google Patents

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.

Here, FIGS. 17 and 18 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. 17, 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, as shown in FIG. 18, 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 formed. 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 plasticizing 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 104 . 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, 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.

  Further, as shown in FIGS. 17 and 18, in the plasticized regions 105 and 106, there may be a cavity defect 109 that continues from one side surface 107 to the other side surface 108. The cavity defect 109 contributes to a decrease in watertightness and airtightness between the side surface 107 and the side surface 108 of the metal members 101 and 111.

  From this point of view, the present invention can agitate the abutting portions between the metal members from the front surface side and the back surface 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 bonding 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 agitation is performed from the surface side of the metal member to be joined to the abutting portion between the first metal member and the second metal member; A second main joining step in which friction agitation is performed from the back side of the metal member; a third main joining step in which friction agitation is performed from one side surface of the metal member to be joined to the abutting portion; and the abutting portion. And a fourth main joining step in which friction stir is performed from the other side surface of the metal member to be joined, and the plasticized region formed in the first main joining step and the second main joining step And formed in the third main joining step and the fourth main joining step. Together to overlap and plasticized region that, when the rotation direction of the rotating tool in the first to fourth main bonding step in the same direction, the starting position of the friction stir in the second of the bonding step, the first The friction stirring start position in the third main joining step is set to the friction stirring start position side in the first main joining step and the second position of the friction stirring in the first main joining step. It is set to either one of the friction stirring start position side in the main joining step, and the friction stirring start position in the fourth main joining step is the friction stirring start position side in the first main joining step and the first It is characterized by being set to either one of the friction stir starting positions in the second main joining step .

  According to such a joining method, after the friction stir welding is performed on the abutting portion from the front side and the back surface side of the metal member to be joined, the friction stir welding is performed on the abutting portion from the side surface side of the metal member to be joined. Since the formation regions overlap, there is no continuous gap between the side surfaces. Thereby, the airtightness between both side surfaces and watertightness can be improved.

  Here, a cavity defect that may occur when performing friction stir welding may be formed on the left side in the traveling direction when the rotating tool is rotated to the right, and may be formed on the right side in the traveling direction when the rotating tool is rotated left. Although it is high, by setting the start positions of the third bonding process and the fourth bonding process to the above-described positions, even if there is a continuous cavity defect between the side surfaces, the cavity defect can be divided. . Thereby, the airtightness between both side surfaces and watertightness can be improved. Further, since the rotation direction of the rotary tool is set in the same direction, it is not necessary to change the rotation direction of the rotary tool one by one when performing each main joining step, and workability can be improved.

  Moreover, this invention may perform the temporary joining process of temporarily joining the said butt | matching part before performing at least 1 main joining process among said 1st thru | or 4th each main joining process.

  When performing the first to fourth main joining steps, in order to push the rotary tool into the abutting portion of the first metal member and the second metal member, a force to separate the first metal member and the second metal member acts, Openings may occur at the abutment. However, according to this joining method, the first to fourth main joining steps can be suitably performed by temporarily joining the abutting portions before performing the first to fourth main joining steps.

  Moreover, this invention may perform the preliminary | backup process which arrange | positions a pair of tab material on the both sides of the said abutting part, and preliminarily carries out friction stirring to the abutting part of the said tab material and the said to-be-joined metal member. According to such a joining process, by using the tab material, the temporary joining process and the main joining process can be promptly joined and the finished surface can be joined cleanly.

  In the present invention, a pilot hole may be formed in advance at a position where the rotary tool is to be inserted. 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.

  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.

[First embodiment]
As shown in FIG. 1, the joining method according to the present invention is performed when the outer peripheral four sides of the joined metal member 1 formed by abutting the first metal member 1a and the second metal member 1b are joined by friction stirring. Each of the rotation direction and the traveling direction of the rotary tool G for use is suitably set.
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 and the second tab material used when bonding the metal member 1 to be bonded will be described in detail.

As shown in FIG. 2, the metal member 1 to be joined includes a first metal member 1 a and a second metal member 1 b that are rectangular in cross section, and a butted portion J <b> 1 is formed by abutting each end face. Has been. 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 final joining step, (7) tab material cutting step, (8) third preliminary step, (9) third preliminary step, and (10) third final joining step. , (11) a fourth preparation step, (12) a fourth preliminary step, (13) a fourth main joining step, and (14) a tab material cutting step.

  In addition, as shown in FIG. 1, (2) 1st preliminary process and (3) 1st this joining process are processes performed from the surface A side, (5) 2nd preliminary process and ( 6) The second main joining step is a step executed from the back surface B side, and (9) the third preliminary step and (10) the third main joining step are executed from the first side surface C side. (12) the fourth preliminary step and (13) the fourth main joining step are steps executed from the second side face D side. In the present embodiment, the rotation directions of the temporary welding rotary tool F and the main welding rotary tool G are all 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.

(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 starting position and completion | finish position of friction stirring in the 1st and 2nd main joining process are provided. In the present embodiment, the first preparation step includes a (1-1) abutting step of abutting the first metal member 1a and the second metal member 1b, and first tabs on both sides of the abutting portion J1 of the metal member 1 to be joined. The material 2 and the second tab material 3 are arranged (1-2) The tab material arranging step, and the first tab material 2 and the second tab material 3 are temporarily joined to the metal member 1 to be joined by welding (1-3). A welding process, and (1-4) an installation process in which the metal member 1 to be joined is installed on a frame of a friction stirrer (not shown).

(1-1) Butting Step In the matching step, as shown in FIGS. 2 and 3, 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. 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 back surface 13a of the first metal member 1a and the back surface 13b of the second metal member 1b are flush with each other. 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.

  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 Step In the tab material arrangement step, as shown in FIG. 2B, the first tab material 2 is arranged on the first side C side of the abutting portion J1, and the contact surface thereof. 21 is brought into contact with the first side face C. Furthermore, the 2nd tab material 3 is arrange | positioned in the 2nd side surface D of the abutting part J1, and the contact surface 31 is made to contact | abut to the 2nd side surface D. 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) Welding process In the welding process, as shown in FIGS. 2A and 2B, the corners 2a and 2b formed by the metal member 1 and the first tab member 2 are welded. Then, the metal member 1 to be joined and the first tab member 2 are temporarily joined. 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.

(1-4) Installation process In the installation process, the metal member 1 to which the first tab material 2 and the second tab material 3 are temporarily welded is placed on a frame of a friction stirrer (not shown), for example, using a clamp. To restrain it from moving. The friction stirrer according to the present embodiment is a device that is set to perform friction stirrer from above the bonded metal member 1.
In addition, when a welding process is abbreviate | omitted in a 1st preparatory process, you may perform a butt | matching process and a tab material arrangement | positioning process on the mount frame of the friction stirring apparatus which is not shown in figure.

(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 second tab member to be joined. (2-1) the second tab material joining step, which joins the butting portion J3 with the joint 3, and the joining portion J1 of the joined metal member 1 are temporarily joined (2-2) the temporary joining step, and the joined metal member 1 (2-3) A pilot hole is formed at the friction stir start position in the first 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 J3, J1, and J2 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 second tab member 3 is provided with the friction stirring start position S _P1 and the first tab member 2 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.

The procedure of friction stirring in the first preliminary process of this embodiment will be described in more detail with reference to FIGS.
First, as shown in FIG. 5 (a), to position the rotary tool F for temporary bonding directly on the start position S _P1 provided in place of the second tab member 3, 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 32 of the second tab member 3, the metal around the stirring pin F2 is plastically fluidized by frictional heat, and the stirring pin F2 is moved to the second tab as shown in FIG. Inserted into the material 3.

  When the entire stirring pin F2 enters the second tab member 3 and the entire lower end surface F11 of the shoulder portion F1 contacts the surface 32 of the second tab member 3, as shown in FIG. While rotating F, it is relatively moved toward the starting point s2 of the second 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 stirring is continuously performed up to the starting point s2 of the second tab member joining step by relatively moving the temporary joining rotary tool F, the second tab member joining is performed without removing the temporary joining rotary tool F at the starting point s2. Move to the process.

(2-1) Second Tab Material Joining Step In the second tab material joining step, friction agitation is performed on the abutting portion J3 between the second tab material 3 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 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 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 second tab member bonding step so that the metal member 1 to be bonded is positioned on the right side of the second 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 second tab material joining step so that the metal member 1 to be joined is located on the left side of the first tab member. 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 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) formed by the material 3 are temporarily joined by welding, no opening is generated between the metal member 1 to be joined and the second tab material 3. .

(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 second tab member 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 2nd 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 second tab material joining step to the start point s1 of the temporary joining step is set to the second tab material 3, and the temporary joining rotary tool F is set to the second tab material joining step. The movement trajectory when moving from the end point e2 to the start point s1 of the temporary joining step is formed in the second tab member 3. 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 in the process from the end point e2 of a 2nd 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 stirring 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 process, the friction stir is continuously performed at the end point e1 up to the start point s3 of the first tab material joining process, and the first 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 step to the start point s3 of the first tab material joining step, and further, the temporary joining rotary tool F is detached at the start point s3. It moves to the 1st 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 first tab member joining step is set to the first tab member 2, and the temporary joining rotary tool F is set to the end point e1 of the temporary joining step. The first tab member 2 is formed with a movement locus when moving from the first tab member joining step to the starting point s3 of the first tab member joining process. 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 1st tab material joining process, obtaining a high quality joined body. Is possible.

(2-3) First Tab Material Joining Step In the first tab material joining step, friction agitation is performed on the abutting portion J2 between the metal member 1 to be joined and the first tab material 2. 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 s3 to the end point e3 of the first 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 first tab material 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. 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 rotary tool F for temporary joining is rotated counterclockwise, the start and end points of the first tab material joining process are set so that the metal member 1 to be joined is positioned on the left side in the traveling direction of the temporary tool F for temporary joining. It is desirable to set the position. Specifically, although illustration is omitted, a starting point is provided at the position of the end point e3 when the temporary joining rotary tool F is rotated to the right, and the position of the starting point s3 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 2 a and 2 b (see FIG. 2) of the material 2 are temporarily joined by welding, no openings are generated between the metal member 1 to be joined and the first tab material 2.

When the rotary tool F for temporary joining reaches the end point e3 of the first tab material joining step, the friction stir is continuously performed until the end position E _P1 provided in the first tab material 2 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 .

(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 at the start position S _M1 set on the surface 22 of the first tab member 2.

  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 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 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 including the temporary joining rotary tool F is located immediately above the end position E _P1 of the first tab member 2 (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, and the work can be omitted. .
In the present embodiment, the first tab member 2 is provided with the friction stirring start position S _M1 and the second tab member 3 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, since the stirring pin G2 is press-fitted while pushing the plastic fluidized metal away from the peripheral surface of the stirring pin G2, it is possible to reduce the press-fitting resistance in the initial press-fitting stage. Since the stirring pin G2 contacts the hole wall of the pilot hole P1 and the frictional heat is generated before the shoulder portion G1 of the main rotating tool G contacts the surface 22 of the first tab member 2, plastic fluidization occurs. It is possible to shorten the time until. 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 process.

  When the entire stirring pin G2 enters the first tab member 2 and the entire lower end surface G11 of the shoulder portion G1 comes into contact with the surface 22 of the first tab member 2, 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 J2 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 joint 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. After the main rotating tool G is relatively moved to the other end of the abutting portion J1, the abutting portion J3 is moved across the abutting portion J3 while performing frictional stirring, and is moved relative to 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 the present embodiment, a re-installation step is provided in which the back surface B side of the bonded metal member 1 is directed upward and is re-installed in a friction stirrer (not shown).

(4-1) Re-installation process In the re-installation process, after releasing the restraint of the bonded metal member 1 that has finished the first main bonding process, the reverse side of the bonded metal member 1 is reversed and the back surface B side is Place it on the base of the friction stirrer again, facing up. 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 Drawing 8 is a sectional view which faces the 1st metal member 1a side from butt J1 after the re-installation process of the 2nd preparatory process concerning a first embodiment. As shown in FIG. 8A, in the re-installation process, when the upper surface of the metal member 1 to be bonded becomes the back surface B and the first metal member 1a is faced from the abutting portion J1 side, The first tab material 2 is located on the left side, and the second tab material 3 is located on the right side.
In addition, depending on the form of the friction stirrer, the front and back 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 J2 between the metal member 1 to be joined and the first tab member 2. (5-1) First tab material joining step, and temporarily joining the butted portion J1 of the metal member 1 to be joined (5-2) Temporary joining step, metal member 1 to be joined and second tab material 3 (5-3) a second 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) first tab material joining step, (5-2) temporary joining step, and (5-3) second tab material joining step, the temporary joining rotary tool F is used.

(5-1) First tab material joining step, (5-2) Temporary joining step and (5-3) Second tab material joining step (5-1) First tab material joining step, (5-2) Temporary The joining step and the (5-3) second tab material joining step are (2-3) the first tab material joining step, (2-2) the temporary joining step and (2-1 ) The process is substantially equivalent to the second tab material joining process. As shown in FIG. 8 (b), 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 successively arranged in this order. 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 first tab material joining step, the (5-2) temporary joining step, and the (5-3) second 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 second tab member 3 side, (2-1) the second tab member joining step, (2-2) the temporary joining step, and (2-3 ) The first tab material joining step was sequentially performed. On the other hand, in the second preliminary process, when facing the metal member 1a side from the abutting portion J1, the first tab member 2 is positioned on the left side of the metal member 1 to be joined and at the time when the first main joining process is completed. Since the friction stirrer equipped with the main rotating tool G for welding is located above the first tab member 2, (5-1) the first tab member joining step from the first tab member 2 side, (5- 2) The temporary joining step and (5-3) the second 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) first tab material joining step, (5-2) temporary joining step, and (5-3) second 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 J2 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 at the start position _SM2 set on the back surface 33 of the second tab member 3 is used. Is inserted (press-fitted), and the inserted stirring pin G2 is moved to the end position E _M2 without being removed. 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 . That is, the start position S _M2 of the second main joining process is located above the end position E _M1 side of the first main joining process. 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, at the time 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 second tab member 3 (see FIG. 8B). Therefore, when the start position _SM2 of the second main joining process is set above the second tab member 3, the first book is moved without moving the friction stirrer equipped with the main joining rotating tool G. A joining process can be performed and a work can be omitted.
Since the second main joining step is substantially the same as the first main joining step, 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 Step In the tab material cutting step, the first tab material 2 and the second tab material 3 are cut from the metal member 1 to be joined. 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. At this time, it is preferable to remove burrs formed on the front surface A and the back surface B of the bonded metal member 1. Thereby, when performing the (8-1) tab material arrangement | positioning process mentioned later, the 1st tab material 2 and the 2nd tab material 3 can be closely_contact | adhered to the to-be-joined metal member 1. FIG.

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 gap (unjoined part) is formed between the first side surface C side and the second side surface D side between the front surface side plasticized region W1 and the rear surface side plasticized region W2. .
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 continuous cavity defects R ₁ and R ₂ occur from the side C side to the second side D side.

(8) Third preparation step The third preparation step is a contact member (first member) in which the friction stirring start position and end position of the metal member 1 to be joined are provided when the friction stir welding on the first side C side is performed. It is a step of preparing one tab material 2 ′ and second tab material 3 ′). In the present embodiment, the third preparation step is to arrange the first tab material 2 ′ and the second tab material 3 ′ on both sides of the abutting portion J1 of the bonded metal member 1 (8-1) Tab material arrangement step The first tab member 2 ′ and the second tab member 3 ′ are temporarily joined to the metal member 1 to be joined by welding (8-2), and the first side C of the metal member 1 to be joined is directed upward. And (8-3) a re-installation step that is installed on a frame of a friction stirrer (not shown).

(8-1) Tab Material Arrangement Step In the tab material arrangement step, as shown in FIG. 11, in the metal member 1 to be joined after the second main joining step, the second surface A is covered to cover the abutting portion J1. The tab material 3 ′ is arranged and the contact surface 31 ′ is brought into contact with the surface A. Further, the first tab member 2 ′ is arranged on the back surface B side so as to cover the abutting portion J1, and the contact surface 21 ′ is brought into contact with the back surface B. At this time, similarly to the (1-2) tab material arrangement step, the front and back surfaces of the first tab material 2 ′ and the second tab material 3 ′ are flush with the first side surface C and the second side surface D.

(8-2) Welding process In the welding process, as shown in FIG. 11, the corners 2a ′ and 2b ′ formed by the metal member 1 and the first tab member 2 ′ are welded to form the metal to be joined. The member 1 and the first tab material 2 ′ are joined. Further, the corners 3a ′ and 3b ′ formed by the metal member 1 and the second tab material 3 ′ are welded to join the metal member 1 and the second tab material 3 ′.

(8-3) Re-installation process In the re-installation process, as shown in FIG. 11, the first side C of the metal member 1 to which the welding process has been finished is directed to the upper surface, and the first metal member 1a from the abutting portion J1. , The metal member 1 to be joined is restrained by a frame of a friction stirrer (not shown) so that the second tab member 3 ′ is located on the left side.
(9) Third preliminary step The third preliminary step includes a pilot hole forming step (9-1) for forming a pilot hole at the start position of the friction stir welding prior to the third main bonding step. .

(9-1) prepared hole forming step the prepared hole forming step, as shown in FIG. 11, a step of the start position S _M3 of the friction stir in the third main bonding step of forming a prepared hole P3. That is, the pilot hole forming step is a step of forming the pilot hole P3 at the position where the stirring pin G2 of the main rotating tool G is to be inserted, as in the pilot hole forming step described above. 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 (9-1) 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.

(10) Third Main Joining Process The third main joining process is a process of joining the abutting portion J1 on the first side face C side of the metal member 1 to be joined. In the third main joining step according to the present embodiment, as shown in FIG. 12, the main joining rotary tool G is used and the main joining is performed in the pilot hole P3 formed in the surface 32 ′ of the second tab member 3 ′. inserting the stirring pin G2 of use rotary tool G (press-fit) to move the stir pin G2 of the inserted end position E _M3 without leaving in the middle (see the traveling direction V _3). That is, the start position S _M3 of the third main bonding step, located on the start position side of the first main bonding step (see the traveling direction V _1).

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 “first side-side plasticized region W3”) is formed. When friction stirring is performed up to the end position E _M3 , as shown in FIG. 13, a punch hole Q <b> 3 is formed on the surface of the first tab member 2 ′, but it remains in the present embodiment.

  Here, when the second main joining step is completed, the friction stirrer provided with the temporary joining rotary tool F is positioned above the first tab member 2 as shown in FIG. ing. Therefore, as shown in FIG. 12, when the start position of the third main joining step is set above the second tab member 3 ′, the friction stirrer provided with the main joining rotary tool G is moved without moving the third stirrer G. This main joining process can be performed, and the work can be omitted. A detailed description of the third main joining step is omitted since it is substantially the same as the first main joining step.

As shown in FIG. 13, when the third main joining step is performed, a part of the front side plasticization region W1 and the back side plasticization region W2 on the first side C side, the first side side plasticization region W3, and Are duplicated. In other words, by a part of the surface side plasticized region W1 and the rear surface side plasticized region W2 are friction stir again, at least partially the first side of the void defects R ₁ and cavity defects R ₂ of the first side surface C side It is divided by the side plasticization region W3. As a result, filling portions S ₁ and S ₂ are formed in the cavity defect R ₁ and the cavity defect R ₂ , respectively.

In the present embodiment, the third preparation step and the third preliminary step are performed before the third main bonding step, but the third preparation step and the third preliminary step (however, The third main joining step may be performed immediately after the second main joining step, omitting the installation step).
Moreover, you may perform an above described 1st tab material joining process, a temporary joining process, and a 2nd tab material joining process before a 3rd main joining process.

(11) Fourth Preparation Step The fourth preparation step is a step performed prior to the fourth main joining step, and in the present embodiment, the second side face D side of the metal member 1 to be joined is directed upward. (11-1) A re-installation step is provided for re-installation in a clamp (not shown).

(11-1) Re-installation process In the re-installation process, after releasing the restraint of the metal member 1 to be bonded after the third main bonding process, the second side surface D is turned upside down. Reinstall it on the base of the friction stirrer (not shown) with the side facing up. In the present embodiment, the metal member 1 to be bonded is rotated halfway around the left and right axes shown in FIG. Thereby, as shown in FIG. 14, while the upper surface of the to-be-joined metal member 1 becomes the 2nd side surface D, when the 2nd metal member 1b is faced from the abutting part J1, 1st tab material 2 'will be located in 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.
(12) Fourth Preliminary Step The second preliminary step is a step that is performed prior to the fourth main joining step, and on the second side face D side, it is lowered to the friction stirring start position in the fourth main joining step. A pilot hole forming step (12-1) for forming a hole is provided.

(12-1) prepared hole forming step the prepared hole forming step, as shown in FIG. 14 (a), a step of the start position S _M4 of the friction stir in the fourth main bonding step of forming a prepared hole P4. 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 (12-1) 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.

(13) Fourth Main Joining Step The fourth main joining step is a step of joining the abutting portion J1 on the second side face D of the metal member 1 to be joined. In the fourth main joining process according to the present embodiment, the main rotating tool G is used for friction stir welding from the second side face D side of the metal member 1 to be joined.

In the fourth main joining step, as shown in FIG. 14A, the stirring pin G2 of the main joining rotary tool G is inserted (press-fitted) into the start position _SM4 provided in the first tab member 2 ′. The inserted stirring pin G2 is moved to the end position E _M4 without being removed halfway. In the fourth main joining step, friction stirring is started from the pilot hole P4, and friction stirring is continuously performed up to the end position E _M4 . That is, the start position S _M4 of the fourth main bonding step, located on the start position side of the second main bonding step (see the traveling direction V _2). When the rotary tool G for main joining is moved, as shown in FIG. 14B, the metal around the stirring pin G2 is plastically fluidized at the same time, and at a position away from the stirring pin G2, plastic flow is caused. The formed metal is hardened again to form a plasticized region (hereinafter referred to as “second side-side plasticized region W4”).

  At the time when the third main joining process is completed, as shown in FIG. 13, the friction stirrer provided with the main joining rotating tool G is positioned above the first tab member 2 '. Then, after the (11-1) re-installation step, the friction stirrer is still located above the first tab member 2 ′ by being rotated halfway around the left and right axes. Therefore, when the start position of the fourth main joining process is set above the first tab member 2 ′, the fourth main joining process is performed without moving the friction stirrer provided with the main welding rotary tool G. Work can be omitted.

Here, when the fourth main joining step is performed, as shown in FIG. 14B, a part on the second side face D side of the front side plasticizing region W1 and the back side plasticizing region W2, The side plasticizing region W4 overlaps. In other words, by a part of the surface side plasticized region W1 and the rear surface side plasticized region W2 are friction stir again, a second side D side void defects R ₁ and at least a portion the second side face of the void defect R ₂ of It is divided by the side plasticization region W4. As a result, filling portions S ₃ and S ₄ are formed in the cavity defect R ₁ and the cavity defect R ₂ , respectively.

  Before performing the fourth main bonding step, the (12-1) pilot hole forming step may be omitted, and the fourth main bonding step may be performed immediately after the third main bonding step. Moreover, you may perform an above described 1st tab material joining process, a temporary joining process, and a 2nd tab material joining process before a 4th main joining process.

(14) Tab material cutting process In the tab material cutting process, after finishing the fourth main bonding process, the first tab material 2 'and the second tab material 3' are cut from the metal member 1 to be bonded (see FIG. 1). ). At this time, it is preferable to remove burrs generated on the first side surface C and the second side surface D of the bonded metal member 1.

According to the joining method according to the present embodiment described above, even if the first metal member 1a and the second metal member 1b are thick as shown in FIG. By performing the friction stir welding, a gap continuous from the first side face C to the second side face D (see the gap 119 in FIG. 18 ) can be filled.

Moreover, when the rotation direction and the advancing direction of the main rotating tool G are set as described above, the first side surface C to the second side surface D extend from the front surface side plasticization region W1 and the rear surface side plasticization region W2. Even if continuous cavity defects R ₁ and R ₂ are formed, the start position S _M3 in the third main bonding process is the start position S _M1 side of the first main bonding process, and the start position in the fourth main bonding process. the S _M4 by the friction stir welding by setting the start position S _M2 side in the second of the welding process, to form a filled portion S ₁ through S ₄ to divide the void defects R _1, R _2, respectively it can.

That is, in this embodiment, since the rotation direction of the main welding rotary tool G is set to the right rotation, the cavity defect R can be formed on the left side in the advancing direction of the front side plasticization region W1 and the back side plasticization region W2. There is a high possibility that a relatively high density plasticized region is formed on the right side in the traveling direction. When the characteristics of the friction stir welding are used, as shown in FIGS. 1A and 1B, there is a high possibility that the cavity defects R ₁ and R ₂ are formed in the second metal member 1b. Set the start positions of the rotary tool G for main bonding in the third main bonding process and the fourth main bonding process as described above, so that both ends of the cavity defects R ₁ and R ₂ have a relatively high density. It can be divided in the plasticized region. Thereby, the to-be-joined metal member 1 with higher watertightness and airtightness between the 1st side surface C and the 2nd side surface D can be manufactured.

Here, when the main rotating tool G for joining crosses the abutting portions J2 and J3, an oxide film may be formed in the plasticized regions W1 to W4. For example, as shown in FIG. 7B, when performing friction stir welding from the metal member 1 to be joined to the second tab member 3, when crossing the abutting portion J <b> 3, The oxide film formed between the tab material 2 is wound on the surface side plasticizing region W1 side. The oxide film can be formed on the right side in the advancing direction of the surface side plasticizing region W1 if the main rotating tool G is rotated to the right, and on the left side in the advancing direction of the surface side plasticizing region W1 if rotated counterclockwise. High nature.
However, according to the present embodiment, since both ends of the plasticized regions W1 to W4 are overlapped, the oxide film can be divided and a high-quality product can be manufactured.

  In the present embodiment, as described above, the second tab material joining step, the temporary joining step, and the first tab material joining step are performed, but the present invention is not limited to this. For example, it is not necessarily a one-stroke procedure, and frictional stirring may be performed intermittently for each process. Moreover, in this embodiment, although the temporary joining process and this joining process were performed using a pair of tab material, you may perform friction stir welding, without using a tab material. In the present embodiment, the first main joining process is performed immediately after the first preliminary process. However, the first main joining process is performed after the second preliminary process is performed immediately after the first preliminary process. You may perform a process and a 2nd this joining process continuously.

  As described above, the present invention is characterized in that each of the rotation direction and the traveling direction of the main rotating tool G is suitably set when the outer peripheral sides of the metal member 1 to be bonded are bonded by friction stirring. Is. That is, when performing friction stir welding, it is preferable to set the rotational direction and the traveling direction of the main rotating tool G in consideration of the position where the cavity defect R is highly likely to occur. In the first embodiment, the case where the main welding rotary tool G is all rotated to the right has been described. However, the present invention is not limited to this, and various types of bonding can be performed depending on the rotation direction and the traveling direction of the main welding rotary tool G. Possible variations.

[Second Embodiment]
For example, in the first embodiment, the rotation direction of the main rotating tool G for welding is all set to the right rotation, but may be set to all the left rotation as in the second embodiment.
As shown in FIG. 15, when the rotation direction of the main welding rotary tool G is set to the left direction and the first main bonding process is performed on the surface A of the metal member 1 to be bonded in the traveling direction V ₁ , the second In this main joining step, friction stir welding is performed from the end position side of the first main joining step toward the start position side (traveling direction V ₂ ). At this time, since the rotating tool G for main bonding is rotated counterclockwise, the cavity defect R is likely to be formed on the right side in the traveling direction of the front surface side plasticized region W1 and the back surface side plasticized region W2. A highly dense plasticized region is formed. That is, in this case, cavity defects R ₁ and R ₂ are easily formed in the first metal member 1a.

Therefore, the third aspect of the present bonding process performs the friction stir welding in the traveling direction V ₃ from the start position side of the first bonding step. The fourth aspect of the present bonding process performs the friction stir welding in the traveling direction V ₄ from the start position side of the second bonding step. According to the third main bonding step and the fourth main bonding step, stirred friction across the void defects R _1, R ₂ again, Ru is separated by a relatively high density plasticized region. Thus, the filling section S ₁ to S ₄ is formed, it is possible to improve the airtightness and watertightness between the first side face C and a second side face D.

  That is, as shown in the first embodiment and the second embodiment, when the rotation directions of the main welding rotary tool G are all the same direction, the friction stirring start position in the second main welding step is the first book. The friction stirring start position in the third main joining process is set at the friction stirring start position side in the first main joining process and the friction in the second main joining process. Set to either one of the stirring start position side, the friction stirring start position in the fourth main joining step is the friction stirring start position side in the first main joining step and the friction stirring in the second main joining step. What is necessary is just to set to the other one of the starting position side.

[ Reference form]
Further, for example, the joining method according to the reference form shown in FIG. 16 is different from the first embodiment in that the rotation direction of the main joining rotary tool G is not the same direction.

In the joining method according to the third embodiment, in the first main joining step, the rotation direction of the main welding rotary tool G is set to the left rotation, and the first side C side to the second side D side (traveling direction V). Friction stir welding is performed toward ₁ ').
On the other hand, in the second main joining step, the rotation direction of the main welding rotary tool G is set to the right rotation, the start position of the friction stir welding is set to the start position side of the first main joining step, and the first Friction stir welding is performed from the side C side toward the second side D side (see the advancing direction V ₂ ′). In this case, void defects R ₂ formed in void defects R ₁ and the rear surface side plasticized region W2 is formed on the surface side plasticized region W1 is likely to be both formed on the first metal member 1a.

Therefore, in the third main joining step, when the rotation direction of the main welding rotating tool G is set to the left rotation as shown in FIG. 16, the start position of the friction stir welding is set to the start position of the first main joining step. The friction stir welding is performed from the front surface A side to the back surface B side (refer to the traveling direction V3 ′). On the other hand, in the fourth main joining step, when the rotation direction of the main welding rotary tool G is set to the right rotation, the start position of the friction stir welding is set to the end position side of the first main joining step, and the surface A Friction stir welding is performed from the side toward the back B side (see the traveling direction V4 ′). According to the third main joining step and the fourth main joining step, both ends of the cavity defects R ₁ and R ₂ are friction-stirred again and divided in a plasticized region having a relatively high density. Thus, the filling section S ₁ to S ₄ is formed, it is possible to improve the airtightness and watertightness of the first side C and a second side D side.

  That is, as shown in FIG. 16, in the first main joining step, the main welding rotary tool G is rotated counterclockwise so that the first metal member 1a is positioned on the right side in the traveling direction of the main welding rotary tool G. On the other hand, in the second main joining process, when the main welding rotary tool G is rotated to the right and the first metal member 1a is set to be positioned on the left side in the traveling direction of the main welding rotary tool G, the third In the main joining step and the fourth main joining step, if the main welding rotary tool G is rotated to the right, the main welding rotary tool G is set so that the first metal member 1a is positioned on the right side in the traveling direction. If the main welding rotation tool G is counterclockwise, the first side surface C and the second side surface D side are set when the traveling direction of the main welding rotation tool G is set so that the first metal member 1a is positioned on the left side in the traveling direction. The airtightness and watertightness of the can be further increased.

  Although not specifically illustrated, in the first main joining step, the main welding rotary tool G is rotated to the right so that the first metal member 1a is positioned on the right side in the traveling direction of the main welding rotary tool G. On the other hand, in the second main joining process, when the main welding rotary tool G is rotated counterclockwise so that the first metal member 1a is positioned on the left side in the traveling direction of the main welding rotary tool G, In the third main joining process and the fourth main joining process, if the main welding rotary tool G rotates rightward, the traveling direction of the main welding rotating tool G is such that the first metal member 1a is positioned on the left side in the traveling direction. If the rotation direction of the main welding rotation tool G is set so that the first metal member 1a is positioned on the right side of the traveling direction if the rotation tool G for main bonding is counterclockwise rotation, To further improve the air tightness and water tightness on the two side D Kill.

  As described above, in the joining method according to the present invention, various combinations of friction stir welding are conceivable depending on the rotation direction and the traveling direction of the main joining rotary tool G.

  The present invention can be modified as appropriate without departing from the spirit of the present invention. For example, the friction stirrer according to the present embodiment performs friction stir from above the metal member to be joined, but is not limited to this, and the rotary tool for main welding around the metal member to be joined. Friction stirring may be performed while moving. The first metal member 1a and the second metal member 1b may be hollow members.

It is the figure which showed the joining method which concerns on 1st 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 1st preparatory process which concerns on 1st embodiment, (a) is a perspective view, (b) is a top view. (2) It is the figure which showed 1st preparatory process which concerns on 1st embodiment, (a) is II sectional view taken on the line of (b) of FIG. 2, (b) is (b) of FIG. Is a sectional view taken along line II-II in FIG. It is the figure which showed the rotary tool which concerns on 1st embodiment, Comprising: (a) is a side view of the rotary tool for temporary joining, (b) is a side view of the rotary tool for main joining. It is the figure which showed the use condition of the rotary tool for temporary joining which concerns on 1st embodiment, (a) is the figure which made the rotary tool for temporary joining contact the 2nd tab material, (b) These are the figures which pushed the rotation tool for temporary joining into the 2nd tab material. It is the top view which showed the 2nd tab material joining process of the 1st preliminary process which concerns on 1st embodiment, the temporary joining process, and the 1st tab material joining process. It is sectional drawing which showed the 1st main joining process which concerns on 1st embodiment in the III-III arrow direction of FIG. 6, Comprising: (a) is a starting position, (b) is an intermediate part, (c) is complete | finished. It is the figure which showed the friction stir welding of a position. (A) is sectional drawing which faces the 1st metal member 1a side from the abutting part J1 after the re-installation process of the 2nd preparation process which concerns on 1st embodiment. (B) is the top view which showed the 1st tab material joining process of the 2nd preparation process which concerns on 1st embodiment, a temporary joining process, and the 2nd tab material joining process. It is the IV-IV sectional view taken on the line IV-IV of FIG. 8 (b) showing the second main joining process according to the first embodiment, wherein (a) is the start position, and (b) is the friction stir welding of the intermediate part. FIG. It is the perspective view which showed the to-be-joined metal member after the tab material cutting process which concerns on 1st embodiment. It is the perspective view which showed the 3rd preparatory process which concerns on 1st embodiment. It is the perspective view which showed the 3rd main joining process which concerns on 1st embodiment. It is the VV sectional view taken on the line of FIG. 12 which showed the 3rd this joining process which concerns on 1st embodiment. (A) is sectional drawing which faces the 2nd metal member 1b side from the abutting part J1 after the re-installation process of the 4th preparation process which concerns on 1st embodiment. (B) is the figure which showed the 4th main joining process which concerns on 1st embodiment, Comprising: It is sectional drawing which faces the 2nd metal member 1b side from the butt | matching part J1. It is the figure which showed the joining method which concerns on 2nd embodiment, Comprising: (a) is a perspective view, (b) is an expansion perspective view in H part. It is the figure which showed the joining method which concerns on a reference form, Comprising: (a) is a perspective view, (b) is an expansion perspective view in I part. 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 rotary tool for temporary joining G rotational tool for this joining J1 end of ~J3 butting portion P1~P4 lower hole V ₁ ~V ₄ rotating tool advancing direction W1~W4 plasticized region S _M main bonding step of the starting position E _M main bonding step

Claims (4)

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 in which friction agitation is performed from the surface side of the joined metal member with respect to the abutting portion between the first metal member and the second metal member;
A second main joining step in which friction agitation is performed from the back side of the joined metal member with respect to the abutting portion;
A third main joining step in which friction agitation is performed from one side of the joined metal member with respect to the abutting portion;
A fourth main joining step of performing frictional stirring from the other side surface of the joined metal member with respect to the abutting portion,
A plasticized region formed in the first main joining step and the second main joining step;
While overlapping the plasticized region formed in the third main joining step and the fourth main joining step ,
When the rotation direction of the rotary tool in the first to fourth main joining steps is the same direction,
The friction stirring start position in the second main joining process is set on the friction stirring end position side in the first main joining process,
The friction stirring start position in the third main joining step is set to either the friction stirring start position side in the first main joining step or the friction stirring start position side in the second main joining step. And
The friction stirring start position in the fourth main joining step is set to either the friction stirring start position side in the first main joining step or the friction stirring start position side in the second main joining step. The joining method characterized by performing. Before performing at least one main joining step among the first to fourth main joining steps,
The joining method according to claim 1, wherein a temporary joining step of temporarily joining the abutting portions is performed. Wherein placing a pair of tabs material on both sides of the butting portion, claim 1 or claims characterized in that it comprises a preliminary step, performing a preliminary friction stir the butting portion of the object to be joined metal member and said tab member Item 3. The joining method according to Item 2 . The joining method according to any one of claims 1 to 3, wherein a pilot hole is formed in advance at a position where the rotary tool is to be inserted.

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