JP2009125773A - Joining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of joining metallic members through a joint member, a method in which airtightness and the watertightness of the joined metallic members are enhanced by hermetically sealing an unplasticized region exposed between the sides of the metallic members. <P>SOLUTION: The joining method includes: a surface side normal welding step in which friction stirring is performed on the surface A at the butted part J2 between the body of the first metallic member 10a and a joint member 20 and at the butted part J4 between the body of the second metallic member 10b and the joint member 20; a rear side normal welding step in which friction stirring is performed on the rear side B at the butted part J20 between the level parts; and a welding joining step in which welding is performed on the side at the butted parts between the first metallic member 10a and the second metallic member 10b and the joint member 20. The welding joining step is characterized in that an unplasticized region is covered with a weld metal T, a region between the first surface side plasticized region W2 and the second surface side plasticized region W3 formed in the surface normal welding step and the rear side plasticized region W4 formed in the rear side normal welding step. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

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

Conventionally, when the thickness of the metal member is larger than that of the stirring pin of the rotary tool, there is known a joining method in which frictional stirring is performed stepwise through a joint member between metal members having step portions having different thicknesses. It has been.
For example, as shown in FIGS. 24A and 24B, the conventional joining method includes a first metal member 110a including a step 102 having a thickness smaller than that of the main body 101 at the edge of the main body 101, and A joint member U in the abutting step in which the second metal member 110b is abutted between the step portions 102, a step friction agitating step in which friction agitation is performed on the abutting portion Jd between the step portions, and the recess 103 formed in the abutting step. And a friction stirring step of performing friction stirring on the abutting portion Ja of the first metal member 110a and the joint member U and the abutting portion Jb of the second metal member 110b and the joint member U. It has. According to this joining method, even if it is a member with a large thickness of a metal member, metal members can be joined suitably.

  Further, in the above-described conventional joining method, it is preferable to friction stir the abutting portion Jc between the lower surface of the joint member U and the bottom surface of the recess 103 in order to improve the airtightness and watertightness between the side surfaces of the metal member. That is, as shown in FIG. 24B, the depth Wa of the plasticized region W formed by the friction stirring step is set larger than the thickness Ua of the joint member U, and the rotary tool G is reciprocated a plurality of times. Then, the butt portion Jc is frictionally stirred over the entire surface. Thereby, the watertightness and airtightness between the both sides | surfaces of a metal member can be improved.

JP 2004-358535 A (see FIG. 8)

  According to such a conventional joining method, there is a problem that the larger the bottom area of the joint member U, the longer the moving distance of the rotary tool G, and the more complicated the operation. In addition, when the thickness Ua of the joint member U is larger than the depth Wa of the plasticized region W formed in the friction stir process described above, unplasticized regions are generated in the abutting portions Ja, Jb, and Jc. For this reason, it has been difficult to improve water tightness and air tightness between both side surfaces of the metal member.

  From such a viewpoint, the present invention is a method of joining metal members together via a joint member, and easily seals an unplasticized region exposed between the side surfaces of the metal member, It is an object of the present invention to provide a bonding method that improves water tightness.

  The joining method according to the present invention that solves such a problem is a method in which the stepped portions of a pair of metal members each having a stepped portion having a thickness smaller than that of the main body portion are abutted to each other on the edge portion of the main body portion. A joining step of forming a recess in the recess, a joint member arranging step of placing a joint member in the recess, a joining portion of the body portion of the one metal member and the joint member, and a body portion of the other metal member and the A front surface main joining step in which friction agitation is performed from the front surface with respect to the abutting portion with the joint member, a back surface main joining step in which friction agitation is performed from the back surface with respect to the abutting portion between the stepped portions, a pair of the metal members and the above A welding joint process for welding from the side surface to the abutting portion with the joint member, and the welding joint process includes a surface side plasticizing region formed in the front surface main joining process and a back surface main joining process. Between the formed back side plasticization region Wherein the covering non-plasticized region in the weld metal.

  The present invention also includes a joint member insertion step of inserting a joint member into a hollow portion formed by the concave groove while abutting a pair of metal members having a concave groove on an end surface with the end surface, and a pair of the metal A front surface main joining step in which friction agitation is performed from the front surface to the abutting portion of the member, a back surface main joining step in which friction agitation is performed from the rear surface to the abutting portion of the pair of metal members, and the pair of metal members and the joint A welding joint process for welding from the side to the abutting portion with the member, wherein the welding joint process is formed by the surface side plasticization region formed by the front surface main joining process and the back side main joining process. An unplasticized region between the formed back side plasticized region is covered with a weld metal.

  According to such a joining method, welding is performed from the side surface to the abutting portions exposed on the side surfaces of the pair of metal members, and the weld metal is overlapped with the front side plasticizing region and the back side plasticizing region, thereby the abutting portion. Can be easily sealed without a gap. Thereby, the airtightness between the side surfaces of a pair of metal members and watertightness can be improved.

  Moreover, it is preferable that the said surface side plasticization area | region and the said back surface side plasticization area | region contact the said joint member. According to this joining method, the abutting portion exposed on the side surface of the metal member can be reliably sealed.

  In addition, the present invention includes a side groove forming step of forming a side groove along the abutting portion between a pair of the metal member and the joint member before the welding joining step, and the welding joining step In this case, it is preferable to include a weld metal filling step of filling the side groove with the weld metal.

  According to this joining method, the workability of welding can be improved by filling the side groove with the weld metal.

  Further, according to the present invention, the width of the side groove formed in the front side plasticization region and the back side plasticization region is larger than the width of the front side plasticization region and the back side plasticization region. Small is preferable. According to such a joining method, since the range in which the weld metal is filled can be reduced, work efficiency can be improved.

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

  Moreover, it is preferable that this invention includes the pilot hole formation process which forms a pilot hole previously in the insertion insertion position of the rotary tool used by the said friction stirring. According to such a joining process, 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, when joining metal members with a joint member interposed therebetween, the non-plasticized region exposed between the side surfaces of the metal members can be easily sealed, Water tightness can be increased.

[First embodiment]
The best embodiment of the joining method according to the present invention will be described with reference to the drawings. FIG. 1 is an overall perspective view showing a joining method according to the first embodiment. As shown in FIG. 1, the joining method according to the first embodiment includes a first metal member 10a, a second metal member 10b, and a joint interposed between the first metal member 10a and the second metal member 10b. Friction stirring is performed from the front surface A and the back surface B to the abutting portion of the metal member H to be joined having the member 20, and welding is performed to the abutting portions exposed to the first side surface C and the second side surface D, respectively. Is. Hereinafter, each step will be described in detail. Also, the vertical and horizontal directions in this description follow the arrows in FIG.

  The joining method according to the present embodiment includes (1) a joining step, (2) a first step temporary joining step, (3) a first step main joining step, (4) a joint member arranging step, and (5) a temporary surface. It includes a joining step, (6) front surface main joining step, (7) back surface main joining step, and (8) welding joining step.

First, the first metal member 10a and the second metal member 10b, which are two metal members, will be described with reference to FIG.
The first metal member 10a and the second metal member 10b are made of a friction-stirring metal material such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium alloy, magnesium, and magnesium alloy. The first metal member 10a and the second metal member 10b are members having substantially the same shape, and are a main body portion Q that is a thick portion, and a step portion R that is formed thinly at the end of the main body portion Q. It is configured with. In the following description, of the side surfaces 11 and 14 of the main body Q, the side surface 11 rising from the surface 16 of the stepped portion R is referred to as the “rising side surface 11”, and the other side surface 14 is referred to as the “exposed side surface 14”. And Further, among the side surfaces 15 and 18 of the step portion R (see FIG. 2D), the side surface 15 butted against the other step portion R is referred to as “abutting side surface 15”, and the other side surface 18 is referred to as “exposed side surface”. 18 ". In this embodiment, the rising side surface 11 of the main body Q rises vertically from the surface 16 of the step portion R (see FIG. 2C) and is parallel to the abutting side surface 15 of the step portion R. (See (b) in FIG. 2).

The step portion R is a portion having a smaller thickness than the main body portion Q, and is formed by chamfering or cutting the surface 12 of the main body portion Q. As shown in FIG. 2 (c), the surface 16 of the step portion R is located one step below the surface 12 of the main body portion Q, but the back surface 17 of the step portion R is the back surface of the main body portion Q. 13 and the same level. Further, the abutting side surface 15 of the step portion R is perpendicular to the surface 16 of the step portion R. The depth dimension of the step portion R (the distance from the rising side surface 11 of the main body portion Q to the abutting side surface 15 of the step portion R) is the radius of the shoulder portion G1 of the large-sized rotary tool G (see FIG. 3B) described later. _{(= Y} 1/2) is greater than. There is no particular limitation on the size of the thickness t _B of the stepped portion R, in this embodiment, is set to 2/3 of the thickness t _A of the main body portion Q.
The first metal member 10 a and the second metal member 10 b are also simply referred to as the metal member 10.

(1) Abutting process As shown in FIG. 2, the abutting process abuts the step portions R and R of the first metal member 10a and the second metal member 10b, and forms a recess 100 between the main body portions Q and Q. It is a process. In the abutting step, the abutting side 15 of the step R of the second metal member 10b is brought into close contact with the abutting side 15 of the step R of the first metal member 10a, and the surface (upper surface) of the step R of the first metal member 10a. 16 and the surface (upper surface) 16 of the step R of the second metal member 10b are flush with each other, and the back surface 17 of the step R of the first metal member 10a and the back surface 17 of the step R of the second metal member 10b are Make it the same. The abutting portion J20 is formed by abutting the step portions R of the first metal member 10a and the second metal member 10b.
When the stepped portions R, R are brought into contact with each other, the rising side surface 11 of one main body portion Q and the rising side surface 11 of the other main body portion Q are connected to a large-sized rotary tool G (FIG. 3B). than the outer diameter Y ₁ of the shoulder portion G1 of reference) will be opposed to each other with a greater distance.

(2) First Step Temporary Joining Process In the first step temporary joining step, as shown in FIG. 4, the abutting portion J10 between the stepped portion R and one tab member 30, and the abutting portion between the stepped portions R and R. The abutting portion J30 between J20 and the step portion R and the other tab member 40 is temporarily joined from the surface side. First, the tab material and the rotation tool will be described.

  The tab members 30 and 40 are disposed so as to sandwich the abutting portion J20. As shown in FIGS. 2A to 2D, the exposed side surfaces 18 and 18 of the step portions R and R are respectively provided. It has dimensions and shapes that can be covered. The tab members 30 and 40 according to the present embodiment are abutted not only on the exposed side surfaces 18 and 18 of the step portions R and R but also on the exposed side surfaces 14 and 14 of the main body portions Q and Q. Each of the tab members 30 and 40 has the same thickness as the thickness of the step R (see FIG. 2D), and is flush with the front surface 16 and the back surface 17 of the step R. In this state, it is joined to the exposed side surfaces 14 and 14 of the main body portions Q and Q by welding. Although there is no restriction | limiting in particular in the material of the tab materials 30 and 40, it forms with the metal material of the same composition as the metal member 10 in this embodiment. An abutting portion J10 is formed at the abutting portion between the tab member 30 and the metal member 10, and an abutting portion J30 is formed at the abutting portion between the tab member 40 and the metal member 10.

  First, referring to FIG. 3, a small rotating tool F (hereinafter referred to as “small rotating tool F”) and a rotating tool G that is relatively larger than the small rotating tool F (hereinafter referred to as “large rotating tool G”). Will be described in detail.

  A small rotary tool F shown in FIG. 3A is made of a metal material harder than the metal member 10 such as tool steel, and protrudes from a shoulder portion F1 having a cylindrical shape and a lower end surface F11 of the shoulder portion F1. And a stirring pin (probe) F2. The size and shape of the small rotary tool F may be set according to the material, thickness, etc. of the metal member 10, but at least smaller than the large rotary tool G (see FIG. 3B). In this way, it is possible to perform friction stir welding with a smaller load than when the large rotary tool G is used, so it is possible to reduce the load applied to the friction stirrer, and further to the small rotary tool F. Since the moving speed (feeding speed) can be made higher than the moving speed of the large rotary tool G, the working time and cost required for the friction stir welding 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 a large rotating 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, than the maximum outer diameter of the maximum outer diameter of the stirring pin G2 of (upper diameter) X ₂ is large rotating tool G (upper end diameter) Y ₂ It is small, and is smaller than the minimum outer diameter minimum outer diameter (bottom diameter) X ₃ is the stirring pin G2 (lower diameter) Y _3. Also, the length L _A of the stirring pin F2, is smaller than the length L _B of the stirring pin G2 of the large rotating tool G.

  The large rotary tool G shown in FIG. 3B is made of a metal material harder than the metal member 10 such as tool steel, and protrudes from a shoulder portion G1 having a cylindrical shape and a lower end surface G11 of the shoulder portion G1. And a stirring pin (probe) G2.

The lower end surface G11 of the shoulder portion G1 is formed in a concave shape like the small rotary tool F. The stirring pin G2 hangs down from the center of the lower end surface G11 of the shoulder 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. The length L _B of the stirring pin G2 is desirably set to be not less than 1/2 and not more than 3/4 of the thickness t _B (see FIG. 2C) of the stepped portion R, and more preferably 1.01 ≦ 2L _B / t _B ≦ 1.10 is preferably set so as to satisfy the relationship.

In the first step temporary joining step, as shown in FIG. 4, one small rotating tool F is moved so as to form a one-stroke writing movement trajectory (bead), and the abutting portions J10, J20, and J30 are moved. Friction stirring is continuously performed from the surface 16 side. That is moved to the end position E _P without disengaging the stirring pin F2 small rotary tool F which is inserted into the start position S _P output friction stir (see (a) in FIG. 3) in the middle. By performing the first step temporary joining step, it is possible to prevent the opening of the tab member and the metal member 10 in the first step main joining step to be performed later.
In addition, although the 1st step part temporary joining process became a locus | trajectory as shown in FIG. 4 in 1st embodiment, it is not limited to this and another locus | trajectory may be sufficient.

(3) First step main joining step In the first step main joining step, a large rotary tool G is used, and friction stir is performed from the surface 16 side of the step portion R to the abutting portion J20 in a temporarily joined state. Do. Specifically, as shown in (a) and (b) of FIG. 5, the stirring pin G2 of the large rotating tool G insert (pressed) into the starting position S _M1, disengaging the stirring pin G2 that inserted in the middle Without being moved to the end position E _M1 .

  When the large rotary tool G 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 the first step portion. A plasticized region W1 will be formed. If it is desired to repair a bonding defect that may be formed in the first step plasticization region W1, friction stir or welding may be performed on the first step plasticization region W1 as necessary. Good.

  When the first step temporary joining step and the first step main joining step are completed, burrs generated by friction stirring are removed and the surface 16 of the step R (the bottom surface of the recess 100) is chamfered and smoothed. To. Thereby, in the joint member arrangement | positioning process mentioned later, the bottom face of the recessed part 100 and the joint member 20 can be closely_contact | adhered.

(4) Joint member arranging step In the joint member arranging step, as shown in FIGS. 6A and 6B, the joint member 20 is inserted into the recess 100, and the joint member 20 is pushed into both the main body portions Q and Q. And a pair of tab members 1 and 2 are arranged so as to sandwich the joint member 20, and the tab members 1 and 2 are butted against the joint member 20.

  In the following description, of the side surfaces 21 and 22 of the joint member 20, the side surface 21 that faces the side surface of the recess 100 (that is, the rising side surface 11 of the main body Q) is referred to as a “butting side surface 21”, and the others The side surface 22 is referred to as an “exposed side surface 22”. When the tab members 1 and 2 are distinguished, the tab member 1 is referred to as “first tab member 1” and the tab member 2 is referred to as “second tab member 2”.

  The joint member 20 is placed on the bottom surface of the recess 100 (that is, the surface 16 of the stepped portion R). The joint member 20 according to the present embodiment is formed of a plate-like member having substantially the same planar shape (rectangular in the present embodiment) as the concave portion 100. When the joint member 20 is inserted into the concave portion 100, the abutting side surface 21 becomes the main body portion Q. (See FIGS. 7A and 7B), and the exposed side surface 22 is the exposed side surface 14 of the main body Q and the exposed side surface 18 of the stepped portion R (see FIG. 2A). And become the same. Although there is no restriction | limiting in particular in the magnitude | size of the thickness of the joint member 20, In this embodiment, when the joint member 20 is inserted into the recessed part 100 when the depth of the recessed part 100 is set, the surface (upper surface) of the joint member 20 is set. ) 23 and the surface (upper surface) 12 of the main body Q are flush with each other (see FIG. 7B). In addition, although there is no restriction | limiting in particular in the material of the joint member 20, in this embodiment, it forms with the metal material of the same composition as the metal member 10. FIG.

  The tab members 1 and 2 have dimensions and shapes that can cover the main body portions Q and Q appearing on the exposed side surface 22 side of the joint member 20 and the joint (boundary line) of the joint member 20, respectively. The tab members 1 and 2 according to the present embodiment are abutted not only on the exposed side surface 22 of the joint member 20 but also on the exposed side surfaces 14 and 14 of the main body portions Q and Q.

Further, the tab members 1 and 2 are installed so as to be flush with the surface 12 of the main body Q and the surface 23 of the joint member 20 as shown in FIG. In the present embodiment, the first tab member 1 is placed on the surface (upper surface) of the tab member 30 used when joining the step portions R and R, and the main body portions Q and Q are exposed by welding. It is joined to the side surfaces 14 and 14. Similarly, the 2nd tab material 2 is mounted in the surface (upper surface) of the tab material 40 used when joining step part R and R, and the exposed side surfaces 14 and 14 of main-body part Q and Q are welded. To be joined.
A member formed by disposing the joint member 20 on the first metal member 10a and the second metal member 10b is also referred to as a bonded metal member H hereinafter. Moreover, as shown in FIG. 1, the surface of the to-be-joined metal member H is made into the surface A, the back surface is made into the back surface B, one side surface is made into the 1st side surface C, and the other side surface is made into the 2nd side surface D.

(5) Surface Temporary Bonding Step In the surface temporary bonding step, friction agitation is preliminarily performed from the surface A side against the abutting portion exposed on the surface A of the metal member H to be bonded. As shown in FIG. 8, the temporary surface joining step uses a small rotary tool F to abut the joint portion J1 between the first tab member 1 and the joint member 20 (fourth intersection c4 to first intersection c1), the first metal. Abutting portion J2 (first intersection c1 to second intersection c2) between main body Q of member 10a and joint member 20, and abutting portion J3 (second intersection c2 to third intersection) between second tab member 2 and joint member 20 c3) and a step of performing frictional stirring on the abutting portion J4 (third intersection point c3 to fourth intersection point c4) between the main body portion Q of the second metal member 10b and the joint member 20.

In the surface temporary joining step, the friction stir start position S _P and the end position E _P are provided in the first tab member 1, and the small rotary tool F inserted into the start position S _{P is} moved to the end position E _P without being removed halfway. Move relative. That is, in the joint temporary joining step, one small rotary tool F is moved so as to form a one-stroke writing movement trajectory (bead), and friction stir is continuously performed on the abutting portions J1 to J4.

The procedure of friction stirring in the surface temporary joining step will be described in more detail.
Is positioned a small rotary tool F immediately above the start position S _P provided in place of the first tab member 1, followed by a small rotary tool F is lowered while the right rotate with stirring pin F2 (shown in FIG. 3 (a) pressing the reference) at the start position _{S P.} The rotational speed of the small rotary tool F is set according to the size and shape of the stirring pin F2, the material and thickness of the metal member 10 to be frictionally stirred, etc., but in many cases 500 to 2000 ( rpm).

  When the stirring pin F2 comes into contact with the surface of the first tab member 1, the metal around the stirring pin F2 is plastically fluidized by frictional heat, and the stirring pin F2 is inserted into the first tab member 1. When the entire stirring pin F2 enters the first tab member 1 and the entire lower end surface F11 of the shoulder portion F1 (see FIG. 3A) contacts the surface of the first tab member 1, the small rotating tool F Is rotated relative to the temporary joining starting point p1 provided at the center of the abutting portion J1 (intermediate between the first intersection c1 and the fourth intersection c4).

  The moving speed (feeding speed) of the small rotary tool F is set according to the size and shape of the agitating pin F2, the material and thickness of the metal member 10 etc. that are frictionally agitated, It is set within a range of 100 to 1000 (mm / min). When the small 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 change of F becomes easy and a complicated movement is attained.

  When the small rotary tool F is relatively moved and frictional stirring is continuously performed up to the temporary joining starting point p1, the small rotating tool F is not detached from the temporary joining starting point p1 and is directly moved to the first intersection c1 which is one end of the abutting portion J1. The friction stir is performed on a part of the abutting portion J1. That is, the friction stir route is set on the joint (boundary line) between the first tab member 1 and the joint member 20, and the small rotary tool F is relatively moved along the route, whereby the friction with respect to the abutting portion J1. Stir.

  Note that when the stirring pin F2 of the small rotary tool F enters the abutting portion J1, a force acts to separate the first tab member 1 and the joint member 20, but the first tab member 1 is welded to the main body Q. Therefore, no opening is generated between the first tab member 1 and the metal member 10.

  When the small rotary tool F is relatively moved to the first intersection c1, the abutting portion J5 between the first tab member 1 and the main body portion Q of the first metal member 10a without detaching the small rotary tool F at the first intersection c1. Is moved relative to the first intermediate point m1 provided in the above, and friction agitation is performed on the abutting portion J5.

  When the small rotary tool F is relatively moved to the first intermediate point m1, the small rotary tool F is allowed to enter the first tab member 1 at the first intermediate point m1 without being detached, and the first tab member 1 is rubbed against the first tab member 1. While stirring, the relative movement is made to the first intersection c1, which is also one end of the abutting portion J2. That is, the friction stir route for returning the small rotary tool F from the first intermediate point m1 to the first intersection c1 is set in the first tab member 1. If it does in this way, when returning the small rotation tool F from the 1st intermediate point m1 to the 1st intersection c1, it becomes difficult to generate | occur | produce a joining defect in the metal member 10 or the joint member 20, Therefore Obtaining a high quality joined body Is possible.

  When the small rotary tool F is returned to the first intersection c1, the small rotary tool F is directly moved into the abutting portion J2 at the first intersecting point c1, and the abutting portion J2 is frictionally agitated with respect to the abutting portion J2. The relative movement is made to the second intersection c2 which is the other end. That is, when the small rotary tool F is returned to the first intersection c1, a route for friction stirring is set on the joint (boundary line) between the main body portion Q of one metal member 10 and the joint member 20, and the small size along the route is small. By relatively moving the rotary tool F, friction agitation is performed on the abutting portion J2.

  When the small rotary tool F is relatively moved to the second intersection c2, the small rotary tool F is allowed to enter the second tab member 2 as it is without being detached at the second intersection c2, and friction stirring is performed on the second tab member 2. While performing, it is relatively moved to the second intermediate point m2 provided at the abutting portion J6 between the second tab member 2 and the main body portion Q of the first metal member 10a. That is, the friction stir route from the second intersection c2 to the second intermediate point m2 is set in the second tab member 2.

  When the small rotary tool F is relatively moved to the second intermediate point m2, the small rotary tool F is not moved at the second intermediate point m2 and is moved relative to the second intersection c2 which is also one end of the abutting portion J3. Friction stirring is performed on the abutting portion J6. That is, the friction stir is also applied to the abutting portion J6 by relatively moving the small rotary tool F along the friction stir route provided on the joint (boundary line) between the second tab member 2 and the main body Q. Do.

  When the small rotary tool F is relatively moved to the second intersection c2, the small rotary tool F is moved relative to the third intersection c3 which is the other end of the abutting portion J3 without detaching the small rotary tool F at the second intersection c2. Friction stirring is performed on the part J3. That is, when the friction stir is continuously performed up to the second intersection c2, the friction provided on the joint (boundary line) between the second tab member 2 and the main body Q without terminating the friction agitation at the second intersection c2. By relatively moving the small rotary tool F along the agitation route, friction agitation is performed on the abutting portion J3.

  When the small rotary tool F is relatively moved to the third intersection c3, the abutting portion J7 between the second tab member 2 and the main body portion Q of the second metal member 10b is left without removing the small rotary tool F at the third intersection c3. Is moved relative to the third intermediate point m3 provided on the front side, and friction agitation is performed on the abutting portion J7. That is, when the friction stir is continuously performed up to the third intersection point c3 which is the other end of the abutting portion J3, the joint between the second tab member 2 and the main body portion Q without terminating the friction stirring at the third intersection point c3 ( Friction stirring is also performed on the abutting portion J7 by relatively moving the small rotary tool F along the friction stirring route provided on the boundary line.

  When the small rotary tool F is relatively moved to the third intermediate point m3, the small rotary tool F is directly moved into the second tab member 2 at the third intermediate point m3 and is rubbed against the second tab member 2. While stirring, relative movement is made to the third intersection c3 which is also one end of the abutting portion J4. That is, the friction stir route for returning the small rotary tool F from the third intermediate point m3 to the third intersection c3 is set in the second tab member 2.

  When the small rotary tool F is returned to the third intersection c3, the small rotary tool F is inserted into the abutting portion J4 as it is without detaching at the third intersection c3, and the abutting portion J4 of the abutting portion J4 is subjected to friction stirring. The relative movement is made to the fourth intersection point c4 which is the other end. That is, when the small rotary tool F is returned to the third intersection c3, a friction stirring route is set on the joint (boundary line) between the main body portion Q of the other metal member 10 and the joint member 20, and the small size along the route is small. By relatively moving the rotary tool F, friction agitation is performed on the abutting portion J4.

  When the small rotary tool F is relatively moved to the fourth intersection c4, the small rotary tool F is allowed to enter the first tab member 1 without being detached at the fourth intersection c4, and friction stirring is performed on the first tab member 1. While performing, it is relatively moved to the fourth intermediate point m4 provided at the abutting portion J8 between the first tab member 1 and the main body portion Q of the other metal member 10. That is, the friction stir route from the fourth intersection point c4 to the fourth intermediate point m4 is set in the first tab member 1.

  When the small rotary tool F is relatively moved to the fourth intermediate point m4, the small rotary tool F is not moved at the fourth intermediate point m4 and is moved relative to the fourth intersection c4 which is also the other end of the abutting portion J4. Then, friction stirring is performed on the abutting portion J8. That is, the friction stir is also applied to the abutting portion J8 by relatively moving the small rotary tool F along the friction stir route provided on the joint (boundary line) between the first tab member 1 and the main body Q. Do.

  When the small rotary tool F is relatively moved from the fourth intermediate point m4 to the fourth intersection point c4, the small rotary tool F is not detached at the fourth intersection point c4 and is directed toward the temporary joining end point p2 provided in the middle of the abutting portion J1. The friction stir is performed on the abutting portion J1. That is, when the friction stir is continuously performed up to the fourth intersection point c4 which is the other end of the abutting portion J1, the joint between the second tab member 2 and the main body portion Q without terminating the friction stirring at the fourth intersection point c4 ( Friction stirring is performed on the abutting portion J1 by relatively moving the small rotary tool F along the friction stirring route provided on the boundary line.

When the small rotary tool F is relatively moved to the temporary joining end point p2, the small rotary tool F is allowed to enter the first tab material 1 as it is without being detached at the temporary joining end point p2, and friction stirring is performed on the first tab material 1. While performing, relatively move to the friction stirring end position E _P.

When small rotary tool F reaches the end position E _P, it is detached small rotary tool stirring is raised while rotating the F pin F2 (shown in FIG. 3 (a) refer) from the end position E _P.

  In addition, when the small rotary tool F is rotated to the right, there is a possibility that a minute joining defect may occur on the left side in the traveling direction of the small rotary tool F. Therefore, the abutting portion between the tab members 1 and 2 and the joint member 20 When the friction stir is performed along the abutting portions J5 to J8 between the J1, J3 and the tab members 1, 2 and the main body Q, the tab members 1, 2 are positioned on the left side in the traveling direction of the small rotary tool F. It is desirable to set a friction stir route. That is, when the small rotary tool F is rotated to the right, the friction stir route from the temporary joining start point p1 to the temporary joining end point p2 so that the small rotary tool F moves clockwise along the outer edge of the joint member 20. It is desirable to set If it does in this way, since it becomes difficult to generate | occur | produce a joint defect on the joint member 20 side, it becomes possible to obtain a high quality joined body.

  Incidentally, when the small rotary tool F is rotated counterclockwise, there is a possibility that a fine joint defect may occur on the right side in the traveling direction of the small rotary tool F. Therefore, the butt portion between the tab members 1 and 2 and the joint member 20 When performing frictional stirring along the abutting portions J5 to J8 of the J1, J3 and the tab members 1, 2 and the main body Q, the tab members 1, 2 are positioned on the right side in the traveling direction of the small rotary tool F. It is desirable to set a friction stir route. That is, when the small rotary tool F is rotated counterclockwise, the friction from the temporary joining start point p1 to the temporary joining end point p2 so that the small rotary tool F moves counterclockwise along the outer edge (outer periphery) of the joint member 20. It is desirable to set a stirring route.

  In the present embodiment, the route of the surface temporary bonding step is set as described above, but the route is not limited to this route. In addition, it is not always necessary to friction stir in the manner of a single stroke.

Moreover, it is preferable to perform a pilot hole formation process after the surface temporary bonding process is completed. Although the lower hole forming step are not specifically shown, to form a prepared hole to the start position S _M2 of the friction stir in the surface main bonding step. The pilot hole is provided for the purpose of reducing the insertion resistance (press-fit resistance) of the stirring pin G2 of the large rotary tool G. Although there is no restriction | limiting in particular in the form of a pilot hole, For example, a cylindrical shape is preferable.

(6) Surface Main Bonding Step In the surface main bonding step, frictional stirring is performed in earnest from the surface A side against the abutting portion exposed on the surface A of the metal member H to be bonded. That is, the front surface main joining step is a step of performing frictional stirring on the abutting portions J2 and J4 using the large rotating tool G larger than the small rotating tool F. In the present embodiment, the friction stirring performed on the abutting part J2 is referred to as a first surface main joining process, and the friction agitation performed on the abutting part J4 is referred to as a second surface main joining process.

In the surface main joining step, as shown in FIG. 9, the friction stir starting position S _M2 and the end position E _M2 are provided in the first tab member 1, and the large-sized rotating tool G inserted into the starting position S _M2 is separated on the way. The relative position is moved to the end position E _M2 without any movement. That is, in the surface main joining process, the first large surface rotating tool G is moved so as to form a movement trajectory (bead) written in one stroke, and the first surface main joining process and the second surface main joining process are continuously performed. .

The surface main bonding process will be described in more detail. The surface main bonding step, first, the start position S _M2 is positioned a large rotating tool G immediately above the lower hole (not shown) formed in, followed by large rotating tool G right rotate is lowered while stirring pin G2 ( The tip of (see (b) of FIG. 3) is inserted into a pilot hole (not shown).

  When the entire stirring pin G2 enters the first tab member 1 and the entire lower end surface G11 of the shoulder portion G1 (see FIG. 3B) contacts the surface of the first tab member 1, friction stirring is performed. The large rotary tool G is relatively moved toward one end (first intersection c1) of the abutting portion J2, and further enters the abutting portion J2, and the first surface main joining step is performed. When the large rotating tool G 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 to the first surface side. A plasticized region W2 is formed.

  The moving speed (feeding speed) of the large rotary tool G is set according to the size and shape of the stirring pin G2, the material and thickness of the metal member 10 etc. that are frictionally stirred, but in many cases, It is set within the range of 30 to 300 (mm / min).

  When the amount of heat input to the metal member 10 and the joint member 20 is likely to be excessive, it is desirable to cool by supplying water around the large rotary tool G. In addition, when cooling water enters the abutting portion J2 or the like, an oxide film may be generated on the joint surface. In the present embodiment, the metal member 10 (main body portion Q) and the joint are subjected to a surface temporary joining step. Since the joint of the member 20 is closed, it is difficult for cooling water to enter the abutting portion J2 and the like, and therefore there is no possibility of deteriorating the quality of the joint portion.

  When the large rotary tool G enters the abutting portion J2, a route for friction stirring is set on the joint between the main body portion Q and the joint member 20, and the large rotating tool G is moved relative to the abutting portion so that the abutting portion Friction stirring is continuously performed from one end (first intersection c1) to the other end (second intersection c2) of J2.

  When the large rotary tool G is relatively moved to the other end (second intersection point c2) of the abutting portion J2, the large rotary tool G is allowed to enter the second tab member 2 as it is without being detached. While frictional stirring is performed, relative movement is made to one end (third intersection c3) of the abutting portion J4. That is, the friction stir route from the second intersection c2 to the third intersection c3 is set in the second tab member 2.

  When the large rotary tool G is relatively moved to one end (third intersection c3) of the abutting portion J4, the large rotating tool G is directly plunged into the abutting portion J4 at the third intersection c3 without being separated from the abutting portion J4. Relatively moving to the fourth intersection c4, which is the other end of the abutting portion J4, while performing frictional stirring. That is, when the large rotary tool G is relatively moved to one end of the abutting portion J4, a route for friction stirring is set on the joint (boundary line) between the main body portion Q of the other metal member 10 and the joint member 20, and the route The second surface main joining process is performed on the abutting portion J4 by relatively moving the large-sized rotating tool G along.

When the large rotary tool G is relatively moved to the other end (fourth intersection c4) of the abutting portion J4, the large rotary tool G is plunged into the first tab member 1 as it is without being detached, and the first tab member 1 is moved. Relatively moving to the end position E _M2 while performing frictional stirring.

In the surface main joining process, the large rotary tool G is rotated clockwise from the start position S _M2 to the end position E _M2 and the friction stir is performed in the manner of one stroke writing, but is not limited thereto. For example, the large rotary tool G may be rotated counterclockwise, or the large rotary tool G is temporarily detached from either the first tab material 1 or the second tab material 2 instead of the one-stroke method, and the abutting portion You may perform each friction stirring of J2 or J4.

(7) Back surface main joining step In the back surface main joining step, friction stir is applied to the abutting portion J20 of the stepped portions R and R from the back surface B side (the back surface 17 side (see FIG. 7B)) of the metal member H to be bonded. Do. As shown in FIG. 10, after the surface main joining process described above is completed, the metal member H to be joined is released from the restraint of a friction stirrer (not shown) and again so that the back surface B of the metal member H to be joined faces upward. Install.

The back surface main joining step is friction stir without detaching the large rotary tool G along the abutting portion J20 from the start position _SM2 set for the first tab material 1 to the end position E _M2 set for the second tab material 2. It is a process of performing. By the back surface main joining step, the back surface side plasticized region W4 is formed on the back surface B of the metal member H to be joined. As shown in FIG. 1, the back surface side plasticizing region W4 overlaps with the first step plasticizing region W1. Thereby, the abutting portion J20 where the step portion R of the first metal member 10a and the step portion R of the second metal member 10b are abutted is sealed over the entire length in the depth direction. Thereby, the airtightness and watertightness between the side surfaces of the to-be-joined metal member H can be improved.

  In addition, in this embodiment, although the back surface main joining process was performed after front surface main joining, it is not limited to this, For example, you may perform after a 1st step part main joining process. When the back surface main joining process is completed, all the tab members are cut from the metal member H to be joined.

(8) Welding and joining process In the welding and joining process, as shown in FIGS. 11 and 12, welding is performed on the abutting portions exposed on the first side face C and the second side face D side of the metal member H to be joined. That is, as shown in FIG. 11, the first side surface C remains as an unplasticized region after the back surface main joining process is completed, because the lower portions of the butted portion J2 and the butted portion J4 are not frictionally stirred by the large rotating tool G. To do. Further, the abutting portion J21 between the lower surface of the joint member 20 and the bottom surface of the recess 100 remains as an unplasticized region. Therefore, in the welding joining process, welding is performed on these unplasticized regions, and the unplasticized regions are sealed with the weld metal. The welding joining process in this embodiment includes a first welding joining process for welding the first side face C and a second welding joining process for welding the second side face D.

  The first welding joining step is filled with a side groove forming step for forming the side groove K on the first side surface C, a weld metal filling step for performing overlay welding on the side groove K, and a weld metal filling step. This includes a cutting step of cutting a portion protruding from the first side surface C of the weld metal T.

  As shown in FIG. 11, the side groove forming step includes a joint portion J2 between the joint member 20 and the first metal member 10a, a joint portion J4 between the joint member 20 and the second metal member 10b, a joint member 20 and a concave portion. This is a step of forming a concave groove across the abutting portion J21 with the bottom surface of 100 and the abutting portion J20 between the step portions R and R. The side groove K is continuously formed along each abutting portion using a known end mill. The shape of the side groove K is not limited, but in the present embodiment, it is formed in a semicircular shape when viewed in cross section. Further, the width Kb of the side groove K is formed smaller than the width W2b of the first surface side plasticizing region W2. Thus, by forming the side groove K small, it is possible to increase the work efficiency of the side groove K forming operation and the weld metal filling process described later.

  In addition, in this embodiment, although the side part ditch | groove K was formed over the full length of the abutting part J2, the abutting part J4, the abutting part J20, and the abutting part J21, it is not limited to this, At least these A side groove K may be formed in the unplasticized region of the butt portion. Also, if a cavity defect or an oxide film is exposed in the first surface side plasticized region W2, the second surface side plasticized region W3, the first step plasticized region W1, and the back side plasticized region W4. The side grooves K are preferably formed so as to include these defects. Thereby, the said cavity defect and an oxide film can be sealed with a weld metal at the weld metal filling process mentioned later.

  In the weld metal filling step, as shown in FIG. 12, build-up welding such as TIG welding or MIG welding is performed on the side groove K to fill the side groove K with the weld metal T. Overlay welding is performed to such an extent that the weld metal T protrudes from the surface of the first side surface C into the side groove K. In this way, by performing the weld metal filling step, the unplasticized regions of the butt portion J2, the butt portion J4, and the butt portion J21 can be reliably sealed. Further, when a cavity defect or an oxide film is exposed in the first surface side plasticized region W2, the second surface side plasticized region W3, the first step plasticized region W1, and the back surface plasticized region W4. These defects can be sealed to improve airtightness and watertightness. Note that, as shown in FIG. 12B, the portion of the weld metal T that protrudes from the first side surface C is defined as a build-up portion T ′.

  In the cutting process, as shown in FIG. 12B, the built-up portion T ′ is cut. The cutting process is performed using a known cutting tool or the like. By performing the cutting step, the first side surface C can be formed smoothly. In addition, like this embodiment, when the weld metal T is formed above the surface A or below the back surface B by the weld metal filling step, the weld metal T is more than the front surface A or the back surface B. It is preferable to cut the protruding portion.

The second welding joining step is formed by a side groove forming step for forming the side groove K on the second side surface D, a weld metal filling step for performing overlay welding on the side groove K, and a weld metal filling step. The cutting process which cuts out the part which protruded from the 2nd side D among the weld metal T which was further included is included.
Since the second welding joining process is substantially the same as the first welding joining process, detailed description is omitted.

According to the joining method according to the first embodiment described above, welding is performed on the abutting portion J2, the abutting portion J4, the abutting portion J20, and the abutting portion J21 exposed on the side surface of the metal member H to be joined. The first surface side plasticizing region W2, the second surface side plasticizing region W3, and the back surface side plasticizing region W4 are overlapped. Thereby, the unplasticized region exposed on the side surface of the metal member H to be bonded can be reliably sealed, and the airtightness and watertightness between the side surfaces of the metal member H to be bonded can be improved. Further, conventionally, there has been a problem that the work becomes complicated when the thickness of the metal member H to be joined becomes large, but according to the welding joint process according to the present embodiment, regardless of the thickness of the metal member H to be joined. The unplasticized region can be easily sealed.
Further, by overlapping the first step plasticization region W1 and the back surface plasticization region W4, the abutting portion J20 of the step portions R and R can be reliably sealed.

  It should be noted that the present invention is not limited to the above-described form and can be appropriately changed without departing from the spirit of the present invention. For example, as shown in FIG. 11, the depths of the first surface side plasticized region W2 and the second surface side plasticized region W3 are made larger than the thickness of the joint member 20, thereby causing the butt portion J2 and the butt portion J4. Friction stirring may be performed over the entire length. When an unplasticized region is formed between the first step plasticized region W1 and the back side plasticized region W4, a welding joint process may be performed to seal the unplasticized region.

[Second Embodiment]
The joining method according to the second embodiment of the present invention is different from the first embodiment in that the joint member is inserted into the hollow portion formed by abutting the first metal member and the second metal member provided with the concave groove. .
FIG. 13 is an overall perspective view showing a joining method according to the second embodiment. As shown in FIG. 13, the joining method according to the second embodiment includes a first metal member 50a, a second metal member 50b, and a joint interposed between the first metal member 50a and the second metal member 50b. Friction stirring is performed on the abutting portions of the front surface A and the back surface B of the metal member N having the member 70 and welding is performed on the abutting portions exposed on the first side surface C and the second side surface D. Features.

  First, the metal member N to be bonded of the bonding method according to the present embodiment will be described in detail, and the tab material used when bonding the metal member N to be bonded will be described in detail.

  As shown in FIGS. 14A and 14B, the metal member N to be bonded is a pair of first metal member 50a and second metal in which concave grooves 90a and 90b are formed at the end portions in this embodiment. It has the member 50b and the joint member 70 inserted in the hollow part formed by abutting the 1st metal member 50a and the 2nd metal member 50b.

The first metal member 50a is a metal member having a rectangular shape in cross section. A concave groove 90a having a trapezoidal cross section that is continuous from one side surface 64a to the other side surface 65a is formed on the end surface 61a of the first metal member 50a. The concave groove 90a is formed at the approximate center in the height direction of the first metal member 50a.
The second metal member 50b is a metal member having a shape substantially the same as that of the first metal member 50a. The concave groove 90b formed in the second metal member 50b is arranged to face the concave groove 90a of the first metal member 50a, and by abutting the first metal member 50a and the second metal member 50b, A hollow portion 91 (see FIG. 14B) is formed.

  In the present embodiment, the first metal member 50a and the second metal member 50b are made of a metal material having the same composition. For example, friction stir such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium alloy, magnesium, magnesium alloy, etc. Made of possible metal material.

  In this embodiment, the joint member 70 is a member made of the same material as that of the first metal member 50a and inserted into the hollow portion 91 formed by the pair of concave grooves 90a and 90b. In the present embodiment, the joint member 70 is a member having a hexagonal shape in cross section, and both end surfaces in the longitudinal direction of the joint member 70 are flush with both side surfaces of the first metal member 50a and the second metal member 50b. It is formed to become. Of the joint member 70, the trapezoidal cross-sectional shape on the side in contact with the first metal member 50a is formed such that the long side is p1 and the short side is p2. The distance from the long side to the short side is p3. On the other hand, the cross-sectional shape of the concave groove 90a of the first metal member 50a is formed such that the long side is q1 and the short side is q2. Further, the distance from the long side to the short side is formed by q3. The relationship between the trapezoidal cross-sectional shape of the joint member 70 on the side in contact with the first metal member 50a and the concave groove 90a of the first metal member 50a is formed by p1≈q1, p2≈q2, and p3≈q3. Yes. That is, as shown in FIG. 14B, the joint member 70 is inserted so that there is almost no gap in the hollow portion 91 formed by the pair of concave grooves 90a and 90b.

  In addition, in this embodiment, although the joint member 70 is formed in the cross sectional view hexagon, it is not limited to this, A cross sectional view rectangle, a cross sectional view circle, etc. may be sufficient. Moreover, you may change suitably the shape of the recessed grooves 90a and 90b of the 1st metal member 50a and the 2nd metal member 50b according to the shape of the coupling member 70. FIG.

  Here, as shown in FIG. 13, the surface of the metal member N to be bonded is the front surface A, the back surface is the back surface B, one side surface is the first side surface C, and the other side surface is the second side surface D. Moreover, as shown to (a) and (b) of FIG. 14, the part where the end surface 61a of the 1st metal member 50a and the end surface 61b of the 2nd metal member 50b were faced is set as the abutting part J51. Further, a portion where the joint member 70 is abutted with the first metal member 50a and the second metal member 50b is referred to as a butting portion J71.

  As shown in FIGS. 15A and 15B, the first tab member 52 and the second tab member 53 are arranged so as to sandwich the butted portion J51 of the metal member N to be joined, respectively. The seam (boundary line) between the first metal member 50a and the second metal member 50b, which is attached to the bonded metal member N 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 52 and the 2nd tab material 53, In this embodiment, it forms with the metal material of the same composition as the to-be-joined metal member N. Further, the shape and dimensions of the first tab member 52 and the second tab member 53 are not particularly limited, but in the present embodiment, the thickness dimension is the same as the thickness dimension of the metal member N to be joined at the abutting portion J51. I have to.

  Hereinafter, the joining method according to the second embodiment will be described in detail. The joining method according to the present embodiment includes (1) a joint member inserting step, (2) a front surface temporary joining step, (3) a front surface main joining step, (4) a back surface temporary joining step, (5) a back surface main joining step, ( 6) Includes a welding process.

(1) Joint member inserting step In the joint member inserting step, as shown in FIG. 14, the end surface 61a of the first metal member 50a and the end surface 61b of the second metal member 50b are brought into close contact with each other, and the grooves 90a and 90b are used. The joint member 70 is inserted into the formed hollow portion 91.
In the joint member inserting step, the surface 62a of the first metal member 50a and the surface 62b of the second metal member 50b are flush with each other, and the back surface 63a of the first metal member 50a and the back surface 63b of the second metal member 50b are flush with each other. To. Similarly, the side surface 64a of the first metal member 50a and the side surface 64b of the second metal member 50b are flush with each other, and the side surface 65a of the first metal member 50a and the side surface 65b of the second metal member 50b are flush with each other. Further, both end surfaces of the joint member 70 are formed flush with both side surfaces of the first metal member 50a and the second metal member 50b.

(2) Surface Temporary Bonding Step The surface temporary bonding step includes a tab material arranging step of arranging a tab material on the metal member N to be joined, a butt portion J52, a butt portion J51, and a butt exposed on the surface A of the metal member N to be joined. A temporary surface bonding step of temporarily bonding the portion J53 from the surface side.

  In the tab material arranging step, as shown in FIGS. 15A and 15B, the first tab material 52 is arranged on the second side surface D side of the abutting portion J51, and the contact surface thereof is the second side surface D. Abut. Furthermore, the 2nd tab material 53 is arrange | positioned to the 1st side surface C of the abutting part J51, and the contact surface is contact | abutted to the 1st side surface C. FIG. At this time, the surface of the first tab member 52 and the surface of the second tab member 53 are flush with the surface A of the metal member N to be joined, and the back surface of the first tab member 52 and the back surface of the second tab member 53 are The back surface B of the bonded metal member N is flush with the surface. The abutting portion J52 is formed on the abutting surface between the first tab member 52 and the metal member N to be joined, and the abutting portion J53 is formed on the abutting surface between the second tab member 53 and the metal member N to be joined. Yes.

  Further, in the tab material arranging step, as shown in FIG. 15B, the corner portions 52a and 52b formed by the metal member N to be joined and the first tab material 52 are welded to join the metal member N to be joined. And the first tab member 52 are temporarily joined. Further, the corners 53 a and 53 b formed by the metal member N and the second tab material 53 are welded to temporarily bond the metal member N and the second tab material 53 to each other. In addition, welding may be performed continuously over the entire length of the corners 52a and 52b and 53a and 53b, or welding may be performed intermittently.

In the surface temporary joining step, as shown in FIG. 16, one small rotating tool F is moved so as to form a one-stroke writing trajectory (bead), and the surface A side with respect to the abutting portions J52, J51, and J53. Friction stir is performed continuously. That is moved to the end position E _P without disengaging the stirring pin F2 small rotary tool F which is inserted into the start position S _P output friction stir (see (a) in FIG. 3) in the middle.
In addition, although the 1st step part temporary joining process became a locus | trajectory as shown in FIG. 17 in 1st embodiment, it is not limited to this, Another locus | trajectory may be sufficient. Moreover, it does not necessarily need to be performed continuously. By performing the surface temporary bonding step, it is possible to prevent the opening of the tab material and the metal member N to be bonded in the surface main bonding step to be performed later.

In addition, it is preferable to perform a pilot hole formation process after the surface temporary joining process is complete | finished. Prepared hole forming step, as shown in FIG. 17 (a), to form a prepared hole P1 at the start position S _M11 of the friction stir in the surface main bonding step. The pilot hole P1 is provided for the purpose of reducing the insertion resistance (press-fit resistance) of the stirring pin G2 of the large rotary tool G. In this embodiment, the stirring pin F2 (see (a of FIG. ) See)) is formed by expanding the diameter of the punched hole formed with a drill (not shown). Although there is no restriction | limiting in particular in the form of the pilot hole P1, In this embodiment, it is cylindrical. In the present embodiment, the pilot hole P1 is formed in the second tab member 53, but the position of the pilot hole P1 is not particularly limited, and may be formed in the first tab member 52, and preferably As in this embodiment, it is desirable to form on the extended line of the joint (boundary line) of the metal member N to be bonded that appears on the surface A side of the metal member N to be bonded.

(3) Surface Main Bonding Step The surface main bonding step is a step of fully bonding the abutting portion J51 on the surface A side of the metal member N to be bonded. In the surface main joining process according to the present embodiment, a large rotating tool G shown in FIG. 3B is used, and friction is caused from the surface A side of the metal member N to be joined against the abutting portion J51 in a temporarily joined state. Stir.

In the surface main joining step, as shown in FIGS. 17A to 17C, the stirring pin G2 of the large rotary tool G is inserted (press-fitted) into the prepared hole P1 formed at the start position _SM11 , and the inserted stirring is performed. The pin G2 is moved to the end position E _M11 without being removed on the way. That is, in the surface 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 _EM11 .

The surface main bonding process will be described in more detail with reference to FIGS.
First, as shown in FIG. 17A, the large rotary tool G is positioned immediately above the _pilot hole P1 (start position S _M11 ), and then the large rotary tool G is moved downward while rotating to the right and the stirring pin Insert the tip of G2 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.

  When the entire stirring pin G2 enters the second tab member 53, as shown in FIG. 17 (b), the large rotating tool G is moved toward one end of the abutting portion J51 of the metal member N to be joined while performing frictional stirring. The relative movement is performed, and the abutting portion J53 is crossed to enter the abutting portion J51. When the large rotating tool G is moved, the metal around the stirring pin G2 is plastically fluidized at the same time, and at a position away from the stirring pin G2, the plastic fluidized metal is hardened again to become surface side plasticized. Region W1 ′ is formed.

  In the present embodiment, the depth Wa of the surface side plasticizing region W1 'is preferably formed to be larger than the distance 70a from the surface A of the metal member N to be joined to the upper end of the joint member 70. That is, by bringing the surface-side plasticized region W1 'into contact with the joint member 70, the friction stir can be performed over the entire length in the depth direction of the abutting portion J51, so that the quality of the product can be further improved.

  When there is a possibility that the amount of heat input to the metal member N to be joined may be excessive, it is desirable to cool the large rotating tool G by supplying water from the surface A side. In addition, when cooling water enters between the first metal member 50a and the second metal member 50b, there is a possibility that an oxide film is generated on the joint surfaces (see the end surfaces 61a and 61b, FIG. 14). Since the joint is closed by executing the temporary joining step, it is difficult for the cooling water to enter between the metal members N to be joined, and there is no possibility of deteriorating the quality of the joined portion.

At the abutting portion J51 of the metal member N to be bonded, a route for friction stirring is set on the joint of the metal member N to be bonded (on the movement locus in the temporary bonding process), and the large rotary tool G is relatively moved along the route. Thus, friction stirring is continuously performed from one end to the other end of the abutting portion J51. When the large rotary tool G is relatively moved to the other end of the abutting portion J51, the abutting portion J52 is traversed while performing frictional stirring, and is relatively moved toward the end position E _M11 . When the large rotary tool G reaches the end position E _M11 , as shown in FIG. 17C, the large rotary tool G is raised while rotating, and the stirring pin G _< b _> 2 is detached from the end position E _M11 .

(4) Back surface temporary bonding step In the back surface temporary bonding step, as shown in FIG. 18, the abutting portion J53 between the metal member N to be bonded and the second tab member 53, the surface to be bonded, on the back surface B side of the metal member N to be bonded. The abutting portion J51 of the metal member N and the abutting portion J52 between the metal member N to be joined and the first tab member 52 are temporarily joined.

As shown in FIG. 18B, the back surface temporary joining step is performed by moving one small rotary tool F so as to form a one-stroke writing trajectory (bead), and in the order of the abutting portions J53, J51, and J52. Continue friction stir at That is moved to the end position E _P without disengaging the stirring pin F2 small rotary tool F which is inserted into the start position S _P output friction stir halfway. End position _{E P} is a starting position _{S M12} of the back main bonding step performed later.

In addition, before performing the back surface main joining process described later, a pilot hole may be formed in advance at a position where the large rotary tool G is to be inserted. That is, as shown in (a) of FIG. 19, it may be formed prepared hole P2 to the starting position S _M12 of the back main bonding step described later.

(5) Back side main joining step The back side main joining step is a step of fully joining the abutting portion J51 exposed on the back surface B of the metal member N to be joined. In the back surface main joining step according to the present embodiment, the large rotating tool G is used, and the friction stir is performed from the back surface B of the metal member N to be joined to the abutting portion J52 in a temporarily joined state.

In the backside main joining step, as shown in FIGS. 19A and 19B, the stirring pin G2 of the large rotary tool G is inserted (press-fitted) into the start position _SM12 set in the first tab member 52, The inserted stirring pin G2 is moved to the end position _EM12 without being removed. In the back surface main joining step, the friction stirring is started from the pilot hole P2, and the friction stirring is continuously performed up to the end position _EM12 . When the large rotating tool G 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 to be plasticized on the back side. Region W2 ′ is formed.

  In the present embodiment, the depth Wa of the back surface plasticizing region W <b> 2 ′ is preferably formed to be larger than the distance 70 a from the back surface B of the metal member N to be joined to the upper end of the joint member 70. That is, by bringing the back side plasticized region W2 ′ into contact with the joint member 70, friction agitation can be performed over the entire length in the depth direction of the abutting portion J52, so that the abutting portion J52 can be reliably sealed. it can. Thereby, the quality of a product can be raised more.

  When the back surface main joining process is completed, the tab material is cut out from the metal member N to be joined as shown in FIG. A front side plasticized region W1 'and a back side plasticized region W2' are formed on the front surface A and the back surface B of the metal member N to be bonded after the back main bonding step. The deepest portions of the front surface side plasticized region W1 'and the back surface side plasticized region W2' are in contact with both ends of the joint member 70, respectively. A part of the abutting portion J71 between the joint member 70, the first metal member 50a, and the second metal member 50b is friction-stirred, but the other part is an unplasticized region.

(6) Welding and joining process The welding and joining process is a process of performing welding along the abutting portion J71 exposed on the first side face C and the second side face D of the metal member N to be joined. That is, the joint member 70 and the groove 90a (see FIG. 14) of the first metal member 50a and the abutting portion J71 between the joint member 70 and the groove 90b of the second metal member 50b are sealed with weld metal. In this embodiment, the welding joining process includes a first welding joining process for welding the first side face C and a second welding joining process for welding the second side face D.

  The first welding joining step includes a side groove forming step for forming the side groove K on the first side C of the metal member N to be joined, a weld metal filling step for performing overlay welding on the side groove K, welding. This includes a cutting step of cutting a portion protruding from the first side surface C of the weld metal T formed in the metal filling step.

In the side groove forming step, as shown in FIG. 21, the side groove K is formed with a predetermined depth along the abutting portion J51 and the abutting portion J71 on the first side face C. In this embodiment, the side groove K is a first groove K ₁ formed along the shape of the joint member 70, and a second groove K _{2 that} communicates from the first groove K ₁ to the surface A. And a third groove portion K ₃ communicating with the back surface B from the first groove portion K ₁ .
First notches section K _1, an end face of the joint member 70, is formed by a part of the first metal member 50a and a second metal member 50b is cut by a known end mill. First notches section K ₁ is formed as the butting portion J71 to the first bottom surface of the groove portion K ₁ by cutting larger than the outer circumference of the end face of the joint member 70 is exposed. First notches section K _1, in the present embodiment, although cutting the end face all of the joint member 70, only to be recessed groove along at least butting portion J71 is formed.

A second groove portion K ₂ third groove portion K ₃ along the butting portion J51, are formed continuously toward the surface A and back B from the first groove portion K _1. A second groove portion K ₂ width Kb of the third groove portion K ₃ is formed smaller than the width Wb of the surface plasticized region W1 'and the rear surface side plasticized region W2'. Further, on the surface side plasticized region W1 'and the rear surface side plasticized region W2' and the tunnel-shaped cavity defects, if the oxide film is caught in a second groove section K ₂ of the third groove portion K ₃ When forming, it is preferable to cut these defective portions. Thereby, the said defect part can be sealed in the welding metal filling process mentioned later.

  In the weld metal filling step, as shown in FIG. 22, build-up welding such as TIG welding or MIG welding is performed on the side groove K to fill the side groove K with the weld metal T1. Overlay welding is performed to such an extent that the weld metal T1 protrudes from the surface of the first side face C into the side groove K. Thus, the unplasticized area | region of the butt | joint part J71 can be reliably sealed by performing a weld metal filling process. Moreover, when a cavity defect and an oxide film are exposed in the surface side plasticization area | region W1 'and back surface side plasticization area | region W2', those defects can also be sealed and airtightness and watertightness can be improved. Note that, as shown in FIG. 22B, a portion of the weld metal T1 that protrudes from the first side surface C is referred to as a built-up portion T1 '.

  In the cutting process, as shown in FIG. 22B, the built-up portion T1 'is cut. The cutting process is performed using a known cutting tool or the like. By performing the cutting step, the first side surface C can be formed smoothly. In addition, like this embodiment, when the weld metal T1 is formed above or below the front surface A or the back surface B by the weld metal filling step, the portions of the weld metal T1 that protrude from the respective surfaces are It is preferable to excise.

The second welding joining step is formed by a side groove forming step for forming the side groove K on the second side surface D, a weld metal filling step for performing overlay welding on the side groove K, and a weld metal filling step. This includes a cutting step of cutting a portion protruding from the second side face D of the weld metal T1.
Since the second welding joining process is substantially the same as the first welding joining process, detailed description is omitted.

  According to the joining method according to the second embodiment described above, welding is performed on the abutting portion J51 and the abutting portion J71 exposed on the side surface of the metal member N to be joined, and the weld metal T1, the surface side plasticized region W1 ′, and By overlapping the back side plasticized region W2 ′, the unplasticized region can be reliably sealed. Thereby, the airtightness and watertightness between the side surfaces of the to-be-joined metal member N can be improved.

As mentioned above, although embodiment of this invention was described, this invention can be changed suitably in the range which is not contrary to the meaning of this invention.
For example, FIG. 23 is a perspective view showing a modification of the second embodiment. In 1st embodiment and 2nd embodiment, although the side part ditch | groove was provided in the 1st side surface C and the 2nd side surface D, and the welding joining process was performed, it is not limited to this. For example, as shown in FIG. 23, an unplasticized region is formed by welding metal T2 by directly welding the abutting portion J71 exposed on the first side surface C and the second side surface D without providing the side groove. It may be sealed. By overlapping the weld metal T2 with the front side plasticization region W1 ′ and the back side plasticization region W2 ′, the unplasticization region exposed on the side surface of the metal member N to be bonded can be reliably sealed. In addition, in the said modification, when welding metal T2 protrudes from the surface of the 1st side surface C and the 2nd side surface D after welding, these protrusion parts are excised and the 1st side surface C and the 2nd side. It is preferable to smooth the side surface D.

  Moreover, in 1st embodiment and 2nd embodiment, although the welding joining process was performed to both the 1st side surface C and the 2nd side surface D, you may perform only to either one.

It is the whole perspective view showing the joining method concerning a first embodiment. It is the figure which showed the 1st metal member, 2nd metal member, and tab material which concern on 1st embodiment, Comprising: (a) is a perspective view, (b) is a top view, (c) is (b). II is a cross-sectional view taken along line II, and FIG. 4D is a cross-sectional view taken along line II-II in FIG. It is the side view which showed the rotary tool which concerns on 1st embodiment, (a) is a small rotation tool, (b) is a large rotation tool. It is the top view which showed the 1st step part temporary joining process which concerns on 1st embodiment. It is the III-III sectional view taken on the line of FIG. 4 which showed the 1st step part main joining process which concerns on 1st embodiment, (a) shows an intermediate point, (b) shows an end point. It is the perspective view which showed the coupling member arrangement | positioning process which concerns on 1st embodiment, Comprising: (a) is an exploded view, (b) is an arrangement | positioning figure. It is the figure which showed the joint member arrangement | positioning process which concerns on 1st embodiment, Comprising: (a) is a top view, (b) is the IV-IV sectional view taken on the line of (a). It is the top view which showed the surface temporary joining process which concerns on 1st embodiment. It is the top view which showed the surface main joining process which concerns on 1st embodiment. It is the top view which showed the back surface main joining process which concerns on 1st embodiment. It is the side view which showed the side part ditch formation process which concerns on 1st embodiment. It is the figure which showed the weld metal filling process which concerns on 1st embodiment, Comprising: (a) is a side view, (b) is a VV sectional view taken on the line. It is the whole perspective view showing the joining method concerning a second embodiment. It is the figure which showed the 1st metal member, 2nd metal member, and joint member which concern on 2nd embodiment, Comprising: (a) is a disassembled perspective view, (b) is a side view. It is the figure which showed the to-be-joined metal member and tab material which concern on 2nd embodiment, Comprising: (a) is a perspective view, (b) is a top view. It is the top view which showed the surface temporary joining process which concerns on 2nd embodiment. FIG. 17 is a cross-sectional view taken along the line VI-VI in FIG. 16 showing the surface main joining process according to the second embodiment, where (a) is a start point, (b) is an intermediate point, and (c) is an end point. Show. It is the figure which showed the back surface temporary joining process which concerns on 2nd embodiment, Comprising: (a) is sectional drawing, (b) is a top view. It is the VII-VII sectional view taken on the line of FIG. 18 which showed the back surface main joining process which concerns on 2nd embodiment, Comprising: (a) shows a starting point and (b) shows an intermediate point. It is the perspective view which showed the state which excised the tab material after the back surface main joining process which concerns on 2nd embodiment. It is the perspective view which showed the side part groove forming process which concerns on 2nd embodiment. It is the figure which showed the weld metal filling process which concerns on 2nd embodiment, Comprising: (a) is a side view, (b) is the VIII-VIII sectional view taken on the line of (a). It is the perspective view which showed the modification which concerns on 2nd embodiment. It is the figure which showed the conventional joining method, (a) is a perspective view, (b) is a side view.

Explanation of symbols

10a First metal member 10b Second metal member 20 Joint member A Front surface B Rear surface C First side surface D Second side surface F Small rotating tool G Large rotating tool H Metal member to be joined J Butt portion K Concave groove P Lower hole T Weld metal W Plasticization region

Claims (7)

A butting step of abutting the stepped portions of a pair of metal members having a stepped portion having a thickness smaller than that of the main body portion at an edge of the main body portion, and forming a recess between the main body portions;
A joint member placement step of placing a joint member in the recess;
Surface main joining step of performing frictional stirring from the surface with respect to the abutting portion between the main body portion of the one metal member and the joint member and the abutting portion between the main body portion of the other metal member and the joint member;
A backside main joining step in which friction stir is performed from the backside against the abutting portions of the stepped portions;
A welding joining step of performing welding from the side surface on the abutting portion between the pair of metal members and the joint member,
In the welding joining step, the unplasticized region between the front side plasticizing region formed in the front surface main joining step and the back side plasticizing region formed in the back side main joining step is covered with a weld metal. The joining method characterized by this. A joint member inserting step of abutting a pair of metal members having a concave groove on the end face with the end face, and inserting a joint member into the hollow portion formed by the concave groove;
Surface main joining step of performing frictional stirring from the surface to the abutting portion of the pair of metal members,
A backside main joining step in which friction agitation is performed from the backside against the abutting portions of the pair of metal members;
A welding joining step of performing welding from the side surface on the abutting portion between the pair of metal members and the joint member,
In the welding joining step, the unplasticized region between the front side plasticizing region formed in the front surface main joining step and the back side plasticizing region formed in the back side main joining step is covered with a weld metal. The joining method characterized by this.   The joining method according to claim 2, wherein the front side plasticization region and the back side plasticization region are in contact with the joint member. Before the welding and joining step, including a side groove forming step of forming a side groove along the abutting portion between the pair of the metal member and the joint member,
The joining method according to any one of claims 1 to 3, further comprising a weld metal filling step of filling the side groove with the weld metal in the welding joining step.   The width of the side groove formed in the front side plasticization region and the back side plasticization region is smaller than the width of the front side plasticization region and the back side plasticization region. The joining method according to claim 4.   The joining method according to any one of claims 1 to 5, further comprising a cutting step of cutting a portion of the weld metal protruding from a side surface of the metal member after the welding joining step. .   The joining method according to any one of claims 1 to 6, further comprising a pilot hole forming step of forming a pilot hole in advance at a position where the rotary tool used for the friction stirring is to be inserted.

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