WO2020158081A1

WO2020158081A1 - Joining method

Info

Publication number: WO2020158081A1
Application number: PCT/JP2019/042274
Authority: WO
Inventors: 堀　久司; 伸城瀬尾; 宏介山中
Original assignee: 日本軽金属株式会社
Priority date: 2019-02-01
Filing date: 2019-10-29
Publication date: 2020-08-06
Also published as: CN113302014B; JP2020124715A; CN113302014A

Abstract

The invention comprises: a preparation step of forming, at the distal end of a column (15), a column step portion (17) having a step bottom surface (17a) and a step side surface (17b) rising obliquely from the step bottom surface (17a) in such a manner that the distal end of the column (15) is tapered; a placement step of placing a seal body (3) on the column (15), thereby forming a first abutment portion (J1) in such a manner that a gap is present when the step side surface (17b) of the column step portion (17) abuts a hole wall (4a) of a hole portion (4); and a main joining step of inserting a rotating distal end side pin into the seal body (3), causing the outer peripheral surface of a proximal end side pin to contact the seal body (3), while causing the outer peripheral surface of the distal end side pin to barely contact the step side surface (17b) of the column step portion (17), and, when moving the rotating tool along the first abutment portion (J1) in this state, performing friction stirring while flowing a second aluminum alloy from the seal body (3) into the gap.

Description

Joining method

The present invention relates to a joining method.

For example, Patent Document 1 discloses a method for manufacturing a liquid cooling jacket. FIG. 11: is sectional drawing which shows the manufacturing method of the conventional liquid cooling jacket. In the conventional method of manufacturing a liquid cooling jacket, a butt portion J10 formed by abutting the step side surface 101c provided on the step portion of the aluminum alloy jacket body 101 and the side surface 102c of the aluminum alloy sealing body 102. Friction stir welding is performed. Further, in the conventional method of manufacturing a liquid cooling jacket, friction stir welding is performed by inserting only the stirring pin F42 into the butt portion J10 while separating the connecting portion F41 of the rotary tool F40 from the jacket body 101 and the sealing body 102. ing. Further, in the conventional method for manufacturing a liquid cooling jacket, the rotation center axis Z of the rotary tool F40 is overlapped with the abutting portion J10 and relatively moved.

JP, 2005-131321, A

Here, the jacket body 101 is likely to have a complicated shape, and is formed of, for example, a cast material of 4000 series aluminum alloy, and a relatively simple shape such as the sealing body 102 is a wrought material of 1000 series aluminum alloy. There is a case where it is formed by. In this way, members having different aluminum alloy grades may be joined together to manufacture a liquid cooling jacket. In such a case, the hardness of the jacket body 101 is generally higher than that of the sealing body 102. Therefore, when friction stir welding is performed as shown in FIG. The material resistance received from the jacket body 101 side is larger than the material resistance received from the jacket body 101 side. Therefore, it becomes difficult to stir different materials with a stirring pin F42 of the rotary tool F40 in a well-balanced manner, and there is a problem that a cavity defect occurs in the plasticized region after joining and the joining strength is reduced.

From this point of view, it is an object of the present invention to provide a joining method capable of suitably joining columns and members of different material types.

The present invention is a joining method for joining a strut and a member having a hole into which the tip of the strut is inserted by friction stirring, wherein the strut is formed of a first aluminum alloy, and the member is It is formed of a second aluminum alloy, the first aluminum alloy is a material having a hardness higher than the second aluminum alloy, the rotary tool used in the friction stirrer comprises a proximal end side pin and a distal end side pin, The taper angle of the base end side pin is larger than the taper angle of the tip end side pin, a stepped step portion is formed on the outer peripheral surface of the base end side pin, and a step bottom surface at the tip of the strut, A step of forming a pillar step portion having a step side surface that obliquely rises from the bottom surface of the step so that the tip of the pillar is tapered; and a step of the pillar step portion by placing the member on the pillar. A mounting step of forming the first butting portion so that there is a gap when the side surface and the hole wall of the hole portion are butted, and the rotating distal end side pin is inserted into the member, and the base end side pin is inserted. When the rotating tool is moved along the first butting portion with the outer peripheral surface of the tip side pin slightly contacting the step side surface of the strut step portion while the outer peripheral surface of the pin contacting the member. And a main joining step of performing frictional stirring while allowing the second aluminum alloy of the member to flow into the gap.

According to the present invention, the second aluminum alloy mainly on the member side of the first butting portion is agitated and plasticized by frictional heat between the member and the pin on the tip side. Therefore, the step side surface of the pillar step portion and the hole wall of the hole portion can be joined at the first butting portion. Further, since the outer peripheral surface of the tip side pin is slightly contacted with the step side surface of the strut step portion, it is possible to minimize the mixing of the first aluminum alloy into the member from the strut. As a result, the second aluminum alloy on the member side is mainly friction-stirred in the first abutting portion, so that the reduction in bonding strength can be suppressed. Further, by pressing the member on the outer peripheral surface of the base end side pin, it is possible to suppress the occurrence of burr.

Further, in the placing step, the step bottom surface of the strut step portion and the back surface of the member are overlapped to form a second butting portion, and in the main joining step, the tip side pin is the step bottom surface of the strut step portion. It is preferable that the rotary tool is moved along the second butting portion while being slightly contacted with the friction stirrer.

According to the present invention, the joint strength of the second butt portion can be increased.

Further, the present invention is a joining method for joining a strut and a member having a hole into which the tip of the strut is inserted by friction stirring, wherein the strut is formed of copper or a copper alloy, and The member is made of aluminum or an aluminum alloy, and the rotary tool used for friction stirring includes a base end side pin and a tip end side pin, and the taper angle of the base end side pin is larger than the taper angle of the tip end side pin. Largely, a step-like step is formed on the outer peripheral surface of the base end side pin, and a step bottom surface is formed at the tip of the pillar, and a step that rises obliquely from the step bottom surface such that the tip of the pillar is tapered. And a step of forming a pillar step portion having a side surface, and by mounting the member on the pillar, there is a gap when the step side surface of the pillar step portion and the hole wall of the hole portion are butted. As described above, the mounting step of forming the first abutting portion and the rotating distal end side pin are inserted into the member, and the outer peripheral surface of the proximal end side pin is brought into contact with the member while the outer peripheral surface of the distal end side pin is contacted. Main welding in which friction stir is performed while the aluminum or aluminum alloy of the member is caused to flow into the gap when the rotary tool is moved along the first butting portion in a state in which is not in contact with the step side surface of the column step portion. And a process.

According to the present invention, the aluminum alloy mainly on the member side of the first butting portion is agitated and plasticized by frictional heat between the member and the tip side pin, and the step side surface and the hole wall of the hole portion are formed in the first butting portion. Can be joined. Further, since the tip side pin is brought into contact with only the member to perform frictional stirring, there is almost no mixing of copper or copper alloy from the column into the member. As a result, the aluminum alloy on the member side is mainly friction-stirred in the first butting portion, so that the reduction in bonding strength can be suppressed. Further, by pressing the member on the outer peripheral surface of the base end side pin, it is possible to suppress the occurrence of burr.

Further, in the placing step, the step bottom surface of the strut step portion and the back surface of the member are overlapped to form a second butting portion, and in the main joining step, the tip side pin is the step bottom surface of the strut step portion. It is preferable that the rotary tool is moved along the second butting portion without being brought into contact with the friction stirrer.

According to the present invention, it is possible to prevent the inflow of copper or copper alloy from the support to the member side in the second butting portion.

Further, in the preparing step, it is preferable that the thickness of the member is set to be larger than the height dimension of the step side surface of the pillar step portion.

According to the present invention, it is possible to prevent metal shortage in the joint portion in the main joining step.

Also, in the main joining step, it is preferable to set the traveling direction and the rotating direction of the rotating tool such that the advancing side of the rotating tool is the strut side.

According to the present invention, the stirring action by the base end side pin and the tip end side pin around the first butting portion is enhanced, and the temperature rise at the first butting portion can be expected. It can be surely joined.

Further, in the main joining step, it is preferable that the rotary tool is moved along the first butting portion to make one round around the support to perform friction stirring.

According to the present invention, it is possible to join the support and the member over the entire circumference of the support.

According to the present invention, it is possible to provide a joining method capable of suitably joining columns and members of different materials.

It is a side view which shows the rotary tool which concerns on embodiment of this invention. It is an expanded sectional view of a rotation tool. It is sectional drawing which shows the 1st modification of a rotary tool. It is sectional drawing which shows the 2nd modification of a rotation tool. It is sectional drawing which shows the 3rd modification of a rotary tool. It is a perspective view which shows the preparation process of the joining method which concerns on embodiment of this invention. It is sectional drawing which shows the mounting process of the joining method which concerns on embodiment. It is a perspective view which shows the joining process of the joining method which concerns on embodiment. It is sectional drawing which shows the joining process of the joining method which concerns on embodiment. It is sectional drawing which shows the joining process of the joining method which concerns on a modification. It is sectional drawing which shows the manufacturing method of the conventional liquid cooling jacket.

Embodiments of the present invention will be described with reference to the drawings as appropriate. First, a rotating tool used in the joining method according to the present embodiment will be described. The rotary tool is a tool used for friction stir welding. As shown in FIG. 1, the rotary tool F is formed of, for example, tool steel, and is mainly configured by a base shaft portion F1, a base end side pin F2, and a tip end side pin F3. The base shaft portion F1 has a cylindrical shape and is a portion connected to the main shaft of the friction stirrer.

　The base end pin F2 is continuous with the base shaft F1 and tapers toward the tip. The proximal pin F2 has a truncated cone shape. The taper angle A of the proximal pin F2 may be set appropriately, but is, for example, 135 to 160°. If the taper angle A is less than 135° or exceeds 160°, the joint surface roughness after frictional stirring increases. The taper angle A is larger than the taper angle B of the tip side pin F3 described later. As shown in FIG. 2, a stepped pin stepped portion F21 is formed on the outer peripheral surface of the base end side pin F2 over the entire height direction. The pin step portion F21 is formed in a spiral shape in a clockwise or counterclockwise direction. That is, the pin step portion F21 has a spiral shape in a plan view and a step shape in a side view. In the present embodiment, since the rotary tool F is rotated clockwise, the pin step portion F21 is set counterclockwise from the base end side toward the tip end side.

When rotating the rotary tool F counterclockwise, it is preferable to set the pin step F21 clockwise from the base end side toward the tip end side. As a result, the plastic flow material is guided to the tip end side by the pin step portion F21, so that it is possible to reduce the metal that overflows to the outside of the metal member to be joined. The pin step portion F21 includes a step bottom surface F21a and a step side surface F21b. The distance X1 (horizontal direction distance) between the vertices F21c and F21c of the adjacent pin step portions F21 is appropriately set according to the step angle C and the height Y1 of the step side surface F21b described later.

The height Y1 of the step side face F21b may be set appropriately, but is set to, for example, 0.1 to 0.4 mm. If the height Y1 is less than 0.1 mm, the joint surface roughness becomes large. On the other hand, when the height Y1 exceeds 0.4 mm, the joint surface roughness tends to increase, and the number of effective step portions (the number of pin step portions F21 in contact with the metal member to be joined) also decreases.

The step angle C formed by the step bottom surface F21a and the step side surface F21b may be set appropriately, but is set to 85 to 120°, for example. The step bottom surface F21a is parallel to the horizontal surface in the present embodiment. The step bottom surface F21a may be inclined in the range of −5° to 15° with respect to the horizontal plane from the rotation axis of the tool toward the outer peripheral direction (minus is downward with respect to the horizontal plane, plus is with respect to the horizontal plane). Above). The distance X1, the height Y1 of the step side surface F21b, the step angle C, and the angle of the step bottom surface F21a with respect to the horizontal plane are set such that the plastic flow material does not stay inside the pin step portion F21 and adhere to the outside during friction stirring. It is set appropriately so that the joint surface roughness can be reduced by pressing the plastic fluidized material at the step bottom surface F21a while being removed.

As shown in FIG. 1, the tip side pin F3 is formed continuously with the base side pin F2. The tip side pin F3 has a truncated cone shape. The tip of the tip side pin F3 is a flat surface F4 perpendicular to the rotation axis. The taper angle B of the tip end side pin F3 is smaller than the taper angle A of the base end side pin F2. As shown in FIG. 2, a spiral groove F31 is formed on the outer peripheral surface of the tip side pin F3. The spiral groove F31 may be either clockwise or counterclockwise, but in the present embodiment, the spiral groove F31 is engraved counterclockwise from the base end side to the tip side in order to rotate the rotary tool F clockwise.

When rotating the rotary tool F counterclockwise, it is preferable to set the spiral groove F31 clockwise from the base end side toward the tip end side. As a result, since the plastic fluid material is guided to the tip side by the spiral groove F31, it is possible to reduce the metal that overflows to the outside of the metal member to be joined. The spiral groove F31 includes a spiral bottom surface F31a and a spiral side surface F31b. The distance (horizontal direction distance) between the vertices F31c and F31c of the adjacent spiral grooves F31 is defined as the length X2. The height of the spiral side surface F31b is defined as the height Y2. The spiral angle D formed by the spiral bottom surface F31a and the spiral side surface F31b is, for example, 45 to 90°. The spiral groove F31 has a role of increasing frictional heat by coming into contact with the metal member to be joined and guiding the plastic fluid material to the tip side.

The design of the rotating tool F can be changed appropriately. FIG. 3 is a side view showing a first modification of the rotary tool of the present invention. As shown in FIG. 3, in the rotary tool FA according to the first modification, the step angle C between the step bottom face F21a of the pin step F21 and the step side face F21b is 85°. The step bottom surface F21a is parallel to the horizontal plane. As described above, the step bottom surface F21a is parallel to the horizontal plane, and the step angle C may be an acute angle within a range in which the plastic fluid material stays in the pin step portion F21 during frictional stirring and is discharged to the outside without adhering. ..

FIG. 4 is a side view showing a second modification of the rotary tool of the present invention. As shown in FIG. 4, in the rotary tool FB according to the second modification, the step angle C of the pin step portion F21 is 115°. The step bottom surface F21a is parallel to the horizontal plane. As described above, the step bottom surface F21a may be parallel to the horizontal plane, and the step angle C may be an obtuse angle within the range of functioning as the pin step portion F21.

FIG. 5 is a side view showing a third modified example of the rotary tool of the present invention. As shown in FIG. 5, in the rotary tool FC according to the third modification, the step bottom surface F21a is inclined upward by 10° with respect to the horizontal plane from the rotation axis of the tool toward the outer peripheral direction. The step side face F21b is parallel to the vertical plane. As described above, the step bottom surface F21a may be formed so as to incline upward from the horizontal surface from the rotation axis of the tool toward the outer peripheral direction within a range in which the plastic fluid material can be pressed during friction stirring. The first to third modified examples of the above rotary tool can also achieve the same effects as the following embodiments.

Next, a joining method according to the embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 6, the joining method of the present embodiment is to join the column 15 and the member (hereinafter, also referred to as “sealing body”) 3 by friction stirring, but here the column 15 is joined. An example of joining the provided jacket body 2 and the sealing body 3 will be described. The present invention is a joining method for joining a support pillar and a member, and the shape of the support pillar, the shape of the member, the use, etc. are not particularly limited.

The joining method of the present embodiment is to manufacture the liquid cooling jacket 1 by friction stir welding the jacket body 2 and the sealing body 3. The liquid cooling jacket 1 is a member that installs a heating element (not shown) on the sealing body 3 and causes a fluid to flow inside to exchange heat with the heating element. In the following description, "front surface" means the surface opposite to the "back surface".

The joining method according to the present embodiment includes a preparation step, a placing step, and a main joining step. The preparation step is a step of preparing the jacket body 2 and the sealing body 3. The jacket body 2 is mainly composed of a bottom portion 10, a peripheral wall portion 11, and a plurality of columns 15. The jacket body 2 is formed mainly including the first aluminum alloy. As the first aluminum alloy, for example, an aluminum alloy casting material such as JIS H5302 ADC12 (Al-Si-Cu system) is used.

As shown in FIG. 6, the bottom portion 10 is a plate-shaped member having a rectangular shape in plan view. The peripheral wall portion 11 is a wall portion that stands up in a rectangular frame shape from the peripheral portion of the bottom portion 10. A peripheral wall step portion 12 is formed on the inner peripheral edge of the peripheral wall portion 11. The peripheral wall step portion 12 is composed of a step bottom surface 12a and a step side surface 12b rising from the step bottom surface 12a. As shown in FIG. 2, the step side surface 12b is inclined so as to spread outward from the step bottom surface 12a toward the opening. The inclination angle β (FIG. 7) of the step side surface 12b may be set appropriately, but is, for example, 3° to 30° with respect to the vertical plane. A concave portion 13 is formed by the bottom portion 10 and the peripheral wall portion 11.

As shown in FIG. 6, the column 15 stands upright from the bottom portion 10. The number of columns 15 is not particularly limited, but four columns are formed in this embodiment. Further, although the pillar 15 has a cylindrical shape in this embodiment, it may have another shape such as a prism. A protrusion 16 is formed at the tip of the column 15. The shape of the protruding portion 16 is not particularly limited, but in this embodiment, it is a truncated cone shape. The height of the protrusion 16 is smaller than the plate thickness of the sealing body 3.

By forming the protruding portion 16, a pillar step portion 17 is formed at the tip of the pillar 15. The column step portion 17 is composed of a step bottom surface 17a and a step side surface 17b rising from the step bottom surface 17a. The step bottom surface 17a is formed at the same height as the step bottom surface 12a of the peripheral wall step portion 12. The height dimension of the step side surface 17b is smaller than the plate thickness of the sealing body 3. The step side surface 17b is inclined so as to be separated from the hole wall 4a so as to taper toward the tip.

The sealing body 3 is a plate-shaped member that seals the opening of the jacket body 2. The sealing body 3 is sized to be placed on the peripheral wall step portion 12. The plate thickness of the sealing body 3 is larger than the height of the step side surface 12b. Holes 4 are formed in the sealing body 3 at positions corresponding to the columns 15. The hole 4 is formed so that the protrusion 16 is fitted therein. The sealing body 3 is formed mainly including the second aluminum alloy. The second aluminum alloy is a material having a lower hardness than the first aluminum alloy. The second aluminum alloy is formed of an wrought aluminum alloy such as JIS A1050, A1100, A6063, for example.

The placing step is a step of placing the sealing body 3 on the jacket body 2 as shown in FIG. 7. In the mounting step, the back surface 3b of the sealing body 3 is mounted on the step bottom surface 12a. The step side surface 12b and the outer peripheral side surface 3c of the sealing body 3 are butted against each other to form a butted portion J11. Further, the step bottom surface 12a and the back surface 3b of the sealing body 3 are butted against each other to form a butted portion J12.

In addition, the hole wall 4a of the hole 4 and the step side surface 17b of the pillar step portion 17 are butted with each other in the placing step to form the first butted portion J1. The first butting portion J1 may include a case where the hole wall 4a and the step side surface 17b of the column step portion 17 are butted with each other with a gap having a substantially V-shaped cross section. Further, the back surface 3b of the sealing body 3 and the step bottom surface 17a of the pillar step portion 17 are butted against each other to form the second butted portion J2.

The main joining step is, as shown in FIGS. 8 and 9, a step of friction stir welding the first butting portion J1 using the rotary tool F. In this step, the tip side pin F3 rotated clockwise is inserted at the start position Sp set on the surface 3a of the sealing body 3. At this time, the outer peripheral surface of the base end pin F2 is brought into contact with the sealing body 3, while the outer peripheral surface of the tip end pin F3 is slightly contacted with the step side surface 17b of the column step portion 17. In this state, when the rotary tool F is moved along the first butting portion J1, the second aluminum alloy of the sealing body 3 is caused to flow into the gap of the first butting portion J1 to perform friction stirring. The rotating tool F is rotated once along the first butting portion J1. A plasticized region W1 is formed on the movement locus of the rotary tool F by hardening the frictionally stirred metal. In the present embodiment, the outer peripheral surface of the tip side pin F3 is slightly contacted with the step side surface 17b of the column step portion 17, and the flat surface F4 of the tip side pin F3 is not contacted with the step bottom surface 17a.

Here, the contact amount of the outer peripheral surface of the tip side pin F3 with respect to the step side surface 17b is defined as the offset amount N. When the outer peripheral surface of the tip side pin F3 slightly contacts the step side surface 17b and the flat surface F4 of the tip side pin F3 does not contact the step bottom surface 17a as in the present embodiment, the offset amount N is set to, for example, , 0<N≦0.5 mm, preferably 0<N≦0.25 mm.

Once the rotary tool F has been rotated around the projecting portion 16, the start end and the end of the plasticized region W1 overlap. The rotating tool F may be gradually lifted and pulled out while relatively moving the rotating tool F on the surface 3a of the sealing body 3.

According to the joining method according to the present embodiment described above, frictional heat between the sealing body (member) 3 and the tip side pin F3 stirs mainly the second aluminum alloy of the first butting portion J1 on the sealing body 3 side. And is plasticized. Therefore, the step side surface 17b of the pillar step portion 17 and the hole wall 4a of the hole 4 can be joined at the first abutting portion J1. Similarly, at the first abutting portion J1, the step bottom surface 17a of the column step portion 17 and the back surface 3b of the sealing body 3 can be joined. Further, since the outer peripheral surface of the tip side pin F3 is only slightly contacted with the step side surface 17b of the column step portion 17, the mixing of the first aluminum alloy from the column 15 into the sealing body 3 can be minimized. As a result, the second aluminum alloy on the side of the sealing body 3 is mainly friction-stirred in the first abutting portion J1, so that the reduction in bonding strength can be suppressed.

Further, in the main joining step, since the step side surface 17b of the strut step portion 17 is tilted in a direction of separating from the hole wall 4a toward the tip (so that the tip of the strut 15 is tapered), the tip side pin F3. It is possible to easily avoid contact between the column 15 and the column 15. Further, in the present embodiment, the inclination angle γ of the step side surface 17b (FIG. 7) and the inclination angle α of the tip side pin F3 (FIG. 1) are the same (the step side surface 17b and the outer peripheral surface of the tip side pin F3 are parallel. Therefore, it is possible to make the tip side pin F3 and the step side surface 17b as close as possible while avoiding contact between the tip side pin F3 and the step side surface 17b.

Further, the rotary tool F of the present embodiment is configured to include a base end side pin F2 and a tip end side pin F3 having a taper angle smaller than the taper angle A of the base end side pin F2. This facilitates insertion of the rotary tool F into the sealing body 3. Further, since the taper angle B of the tip side pin F3 is small, the rotary tool F can be easily inserted to a deep position of the sealing body 3.

Further, since the plastic fluid material can be pressed by the outer peripheral surface of the base end side pin F2, the stepped groove formed on the joint surface can be made small and the bulging portion formed beside the stepped groove. Can be eliminated or reduced. In addition, since the stepped pin step portion F21 is shallow and has a wide outlet, the plastic fluid material easily comes out of the pin step portion F21 while pressing the plastic fluid material with the step bottom face F21a. Therefore, even if the plastic fluid material is pressed by the proximal pin F2, the plastic fluid material is unlikely to adhere to the outer peripheral surface of the proximal pin F2. Therefore, the joint surface roughness can be reduced, and the joint quality can be preferably stabilized.

In the main joining step, the rotation direction and the traveling direction of the rotary tool F may be set as appropriate, but in the plasticized region W1 formed on the movement trajectory of the rotary tool F, the support column 15 side is the shear side, and the sealing is performed. The rotation direction and the traveling direction of the rotary tool F were set so that the body 3 side was the flow side. By setting the support 15 side to be the shear side, the stirring action by the base end side pin F2 and the tip end side pin F3 around the first butting part J1 is enhanced, and the temperature rise at the first butting part J1 can be expected, The step side surface 17b and the sealing body 3 can be joined to each other more reliably at the first butting portion J1.

In addition, the shear side (Advancing side) is the value of the relative speed of the outer circumference of the rotary tool to the welded part, which is the sum of the tangential speed on the outer circumference of the rotary tool and the magnitude of the moving speed. Means the side. On the other hand, the flow side (Retreating side) refers to the side where the relative speed of the rotary tool to the welded part becomes low due to the rotary tool rotating in the direction opposite to the moving direction of the rotary tool.

Also, in the preparation process, the thickness of the sealing body 3 is set to be larger than the height dimension of the step side surface 17b of the column step portion 17. According to such a joining method, it is possible to prevent metal shortage at the joint.

In the main joining process, the step bottom surface 17a of the pillar step portion 17 and the flat surface F4 of the tip pin F3 are separated from each other, but the plasticized region W1 reaches the step bottom surface 17a. Thereby, the joint strength of the second abutting portion J2 can be increased.

In the main joining step, the tip end pin F3 is slightly contacted with the step bottom surface 17a of the column step portion 17, and the rotary tool F is moved along the second butting portion J2 to perform friction stirring. (Not shown). According to such a joining method, it is possible to further increase the joining strength and prevent the first aluminum alloy from being mixed into the sealing body 3 side from the column 15 side as much as possible. Further, the abutting portions J11 and J12 may be appropriately joined by a method such as friction stirring.

[Modification]
Next, a joining method according to a modified example of the present invention will be described. In the modified example, as shown in FIG. 10, the materials of the jacket body 2 and the sealing body 3 are different in the preparation step, and the form of the main joining step is different from the above embodiment. In the preparation process of the modified example, the jacket body 2 is made of copper or a copper alloy. In the modification, the jacket body 2 made of copper or a copper alloy and the sealing body (member) 3 made of aluminum or an aluminum alloy are exemplified, but, for example, a strut made of copper or a copper alloy and the strut You may join with the member made from aluminum or aluminum alloy joined.

In the main joining process of the modified example, as shown in FIG. 10, the rotating tool F is used to friction stir weld the jacket body 2 and the sealing body 3. In the main joining step, friction stir is performed by making a round around the projecting portion 16 without contacting the outer peripheral surface of the tip side pin F3 with the step side surface 17b of the column step 17. In the present embodiment, the tip of the tip pin F3 is set so as not to contact the step bottom surface 17a.

If the distance from the step side surface 17b to the outer peripheral surface of the tip side pin F3 is too large, the joint strength of the first butted portion J1 will be reduced. The separation distance L from the step side surface 17b to the outer peripheral surface of the tip side pin F3 may be appropriately set depending on the material of the step side surface 17b and the sealing body 3. When the outer peripheral surface F10 of the tip side pin F3 is not brought into contact with the step side surface 17b and the flat surface F4 is not brought into contact with the step bottom surface 17a as in the present embodiment, for example, 0≦L≦0.5 mm is set. , Preferably 0≦L≦0.3 mm.

According to the modified example described above, the tip side pin F3 of the rotary tool F and the step side surface 17b of the column step portion 17 are not in contact with each other. However, due to frictional heat between the sealing body 3 and the tip side pin F3, the aluminum alloy mainly on the sealing body 3 side of the first abutting portion J1 is agitated and plasticized, and at the first abutting portion J1 the step side surface 17b is formed. The hole wall 4a of the hole 4 can be joined. Further, since the tip side pin F3 is brought into contact with only the sealing body 3 to perform frictional stirring, there is almost no mixing of copper or copper alloy from the support column 15 into the sealing body 3. As a result, the aluminum alloy on the side of the sealing body 3 is mainly friction-stirred in the first butting portion J1, so that the reduction in the bonding strength can be suppressed.

Also, in the second abutting portion J2 as well, although the tip side pin F3 is not in contact with the step bottom surface 17a, the plasticizing region W1 reaches the step bottom surface 17a, so that the joining strength of the second abutting portion J2 can be increased. Further, also in the second abutting portion J2, since the tip side pin F3 is not in contact with the step bottom surface 17a, there is almost no mixing of copper or copper alloy from the support column 15 into the sealing body 3. Thereby, the aluminum alloy on the side of the sealing body 3 is mainly friction-stirred also in the second butting portion J2, so that the reduction in the bonding strength can be suppressed.

Like the above embodiment, in this modification, the rotary tool F is configured to include a base end side pin F2 and a tip end side pin F3 having a taper angle smaller than the taper angle A of the base end side pin F2. This facilitates insertion of the rotary tool F into the sealing body 3. Further, since the taper angle B of the tip side pin F3 is small, the rotary tool F can be easily inserted to a deep position of the sealing body 3.

Further, in this modification, a gap having a V-shaped cross section is formed in the first butting portion J1, but by making the plate thickness of the sealing body 3 larger than that of the step side surface 17b, the joining portion (in the main joining step ( It is possible to prevent metal shortage in the plasticized region W1).

In the main joining step, the inclination angle γ of the step side surface 17b (FIG. 7) and the inclination angle α of the tip side pin F3 (FIG. 1) are the same (the step side surface 17b and the outer peripheral surface of the tip side pin F3 are parallel to each other. Therefore, it is possible to make the tip side pin F3 and the step side surface 17b as close as possible while avoiding contact between the tip side pin F3 and the step side surface 17b.

The plate thickness of the sealing body 3 may be set to be the same as the height dimension of the protruding portion 16.

3 Sealed body (member)
4 hole 4a hole wall 15 pillar 17 pillar step 17a step bottom 17b step side J1 first butting J2 second butting F rotating tool F2 proximal pin F3 tip pin F21 pin step A taper angle B taper angle

Claims

A joining method for joining a strut and a member having a hole into which the tip of the strut is inserted by friction stirring,
The column is formed of a first aluminum alloy, the member is formed of a second aluminum alloy, the first aluminum alloy is a material having a hardness higher than the second aluminum alloy,
The rotary tool used in the friction stirring includes a base end side pin and a tip end side pin, and the taper angle of the base end side pin is larger than the taper angle of the tip end side pin, and the outer peripheral surface of the base end side pin is A step-like step is formed,
A preparatory step of forming a pillar step portion having a step bottom surface at the tip of the pillar and a step side surface that rises obliquely from the step bottom surface such that the tip of the pillar is tapered;
By placing the member on the column, a placing step of forming the first butting portion so that there is a gap when the step side surface of the column step portion and the hole wall of the hole portion are butted.
The rotating distal end side pin was inserted into the member, and the outer peripheral surface of the base end side pin was brought into contact with the member, while the outer peripheral surface of the distal end side pin was slightly contacted with the step side surface of the strut step portion. In the state, a main joining step of performing friction stirring while flowing the second aluminum alloy of the member into the gap when moving the rotary tool along the first butting portion is included. ..
In the placing step, the step bottom surface of the pillar step portion and the back surface of the member are overlapped to form a second butting portion,
In the main joining step, frictional stirring is performed by moving the rotary tool along the second butting portion in a state in which the tip side pin slightly contacts the step bottom surface of the column step portion. The joining method according to claim 1.
The joining method according to claim 1 or 2, wherein in the preparing step, the thickness of the member is set to be larger than the height dimension of the step side surface of the strut step portion.
The joining method according to claim 1, wherein, in the main joining step, the advancing side and the rotating direction of the rotary tool are set such that the advancing side of the rotary tool is the strut side.
A joining method for joining a strut and a member having a hole into which the tip of the strut is inserted by friction stirring,
The pillar is formed of copper or a copper alloy, the member is formed of aluminum or aluminum alloy,
The rotary tool used in the friction stirring includes a base end side pin and a tip end side pin, and the taper angle of the base end side pin is larger than the taper angle of the tip end side pin, and the outer peripheral surface of the base end side pin is A step-like step is formed,
A preparatory step of forming a pillar step portion having a step bottom surface at the tip of the pillar and a step side surface that rises obliquely from the step bottom surface such that the tip of the pillar is tapered;
By placing the member on the column, a placing step of forming the first butting portion so that there is a gap when the step side surface of the column step portion and the hole wall of the hole portion are butted.
Inserting the rotating distal end side pin into the member, while contacting the outer peripheral surface of the proximal end side pin with the member, while not contacting the outer peripheral surface of the distal end side pin with the step side surface of the strut step portion, A main joining step of performing friction stirring while flowing aluminum or an aluminum alloy of the member into the gap when moving the rotary tool along the first butting portion.
In the placing step, the step bottom surface of the pillar step portion and the back surface of the member are overlapped to form a second butting portion,
In the main joining step, friction stirring is performed by moving the rotary tool along the second butting portion in a state where the tip side pin is not in contact with the step bottom surface of the strut step portion. 5. The joining method according to item 5.
The joining method according to claim 5 or 6, wherein in the preparing step, the thickness of the member is set to be larger than the height dimension of the step side surface of the strut step portion.
The joining method according to claim 5, wherein, in the main joining step, the advancing direction and the rotating direction of the rotating tool are set such that the advancing side of the rotating tool is the strut side.
The joining method according to claim 1 or 5, wherein, in the main joining step, the rotary tool is moved along the first butting portion to make one round around the support column to perform frictional stirring.