JP6662210B2 - Joining method - Google Patents

Description

  The present invention relates to a joining method for joining metal members by friction stir welding.

  Patent Documents 1 and 2 disclose a technique in which metal members are butted in a T-shape in a front view, and the butted portions are friction stir welded. In the related art, after abutting an end surface of a first metal member and a back surface of a second metal member, a rotary tool is inserted from a front surface side of the second metal member to friction stir weld the butted portion.

Japanese Patent No. 3947271 Japanese Patent No. 4056587

  In the related art, frictional stirring is performed by bringing the shoulder portion of the rotary tool into contact with the surface of the second metal member, and thus there is a problem in that the load on the friction stirrer increases. Further, since the shoulder of the rotating tool is brought into contact with the surface of the second metal member, the width of the plasticized region is increased. In order to prevent the plastic fluid from flowing out from the inner corners of the first metal member and the second metal member, the thickness of the first metal member must be increased.

  From such a viewpoint, an object of the present invention is to provide a joining method that can reduce the load applied to the friction stirrer and has a high degree of freedom in design.

In order to solve such a problem, the present invention is a joining method of joining a first metal member and a second metal member using a rotating tool having a stirring pin, wherein the end surface of the first metal member and A butting step of forming a butted portion by butting against a back surface of the second metal member, and an arranging step of arranging an auxiliary member at a position corresponding to the first metal member on the surface of the second metal member, and rotating. inserting the stirring pin from the surface side of the auxiliary member, only the stirring pin, said second metal member and the auxiliary member, or the first metal member is brought into contact with the second metal member and the auxiliary member a friction stir process is relatively moves the rotary tool while friction stir welding the butted portion had a removal step of removing the auxiliary member which burrs are formed from the second metal member, seen including, said friction During the stirring process In the case where the predetermined position through which the rotation center axis of the rotary tool passes is set as a joining reference line, in the arranging step, the auxiliary member is arranged only on one side with respect to the joining reference line, and in the friction stir step, The joining condition is set so that the burrs are generated on the auxiliary member .

According to such a joining method, friction stir welding is performed in a state where only the stirring pin is in contact with the second metal member and the auxiliary member, or the first metal member, the second metal member and the auxiliary member. In comparison, the load on the friction stirrer can be reduced. Further, since only the stirring pin is inserted, the width of the plasticized region can be reduced. Thereby, since the plate thickness of the first metal member can be reduced, design flexibility can be increased. Further, in addition to the first metal member and the second metal member, the auxiliary member is also subjected to friction stir welding, whereby it is possible to prevent shortage of metal at the joint. Preferably, the method further includes a removing step of removing the burr-formed auxiliary member from the second metal member. According to this joining method, the burr can be easily removed together with the auxiliary member. According to such a joining method, the burrs can be concentrated on the auxiliary member disposed only on one side with respect to the joining reference line, so that the burrs can be more easily removed.

Further, a joining method of joining a first metal member and a second metal member using a rotating tool having a stirring pin, wherein an end surface of the first metal member and a back surface of the second metal member are abutted. A butting step of forming a butting portion, an arranging step of arranging an auxiliary member at a position corresponding to the first metal member on the surface of the second metal member, and rotating the stirring pin from the surface side of the auxiliary member. Insert, only the stirring pin, the second metal member and the auxiliary member, or the first metal member, the second metal member and the relative movement of the rotating tool in a state of contacting the auxiliary member A friction stir step of friction stir welding the butted portion; and a removing step of removing an auxiliary member having burrs formed from the second metal member. The shaft passes When the scheduled position is set as a joining reference line, in the arranging step and the friction stirring step, the auxiliary member is arranged so as to straddle the joining reference line, and the auxiliary member on one side with respect to the joining reference line is The arrangement position and the joining condition of the auxiliary member are set such that the burr is generated and the auxiliary member does not remain on the other side after the friction stir process .

According to this joining method, only the stirring pin is connected to the second metal member and the auxiliary member, or the first metal member.
Conventionally, friction stir welding is performed in contact with the metal member, the second metal member, and the auxiliary member.
The load on the friction stirrer can be reduced as compared with the operation. Also, insert only the stirring pin.
Therefore, the width of the plasticized region can be reduced. Thereby, the plate of the first metal member
Since the thickness can be reduced, the degree of freedom in design can be increased. Also the first metal
In addition to the member and the second metal member, the auxiliary member is also subjected to friction stir welding to form a metal at the joint.
Shortage can be prevented. Preferably, the method further includes a removing step of removing the burr-formed auxiliary member from the second metal member. According to this joining method, the burr can be easily removed together with the auxiliary member. According to such a joining method, a shortage of metal at the joint can be prevented in a well-balanced manner. After the friction stir step, the auxiliary members remaining only on one side are removed together with the burrs, so that the burrs can be more easily removed.

  According to the joining method according to the present invention, the load on the friction stirrer can be reduced, and the degree of freedom in design can be increased.

FIG. 3 is a perspective view showing a joining step and an arrangement step of the joining method according to the first embodiment of the present invention. It is sectional drawing which shows the friction stirring process of the joining method concerning 1st embodiment. It is sectional drawing which shows the removal process of the joining method which concerns on 1st embodiment. It is sectional drawing which shows after the removal process of the joining method which concerns on 1st embodiment. It is sectional drawing which shows the butting process and arrangement | positioning process of the joining method which concerns on 2nd embodiment. It is sectional drawing which shows the friction stirring process of the joining method concerning 2nd embodiment. It is sectional drawing which shows the removal process of the joining method concerning 2nd embodiment. It is sectional drawing which shows the butting process and arrangement | positioning process of the joining method which concerns on 3rd embodiment. It is sectional drawing which shows the friction stir process of the joining method concerning 3rd embodiment. It is sectional drawing which shows the removal process of the joining method which concerns on 3rd embodiment.

[First embodiment]
The joining method according to the first embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, in the joining method according to the present embodiment, the first metal member 1 and the second metal member 2 are joined in a T-shape in a front view and joined by friction stirring. In the joining method according to the present embodiment, a butting step, an arrangement step, a friction stir step, and a removing step are performed. Note that the “front surface” in the description means a surface on the opposite side of the “back surface”.

  Each of the first metal member 1 and the second metal member 2 has a plate shape. The first metal member 1 and the second metal member 2 are appropriately selected from friction stirable metals such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium alloy, magnesium, and magnesium alloy. The thickness of the first metal member 1 and the second metal member 2 may be set as appropriate.

  As shown in FIG. 1, the butting process is a process in which the end surface 1 a of the first metal member 1 and the back surface 2 c of the second metal member 2 are butted to form a butted portion J <b> 1.

  The arranging step is a step of arranging the auxiliary member 10 as shown in FIG. The auxiliary member 10 is a plate-shaped metal member. The plate thickness of the auxiliary member 10 is set to such a thickness that a shortage of metal does not occur in a joint (plasticized region W1) formed in a friction stir process described later. In the present embodiment, the auxiliary member 10 is formed of the same material as the first metal member 1 and the second metal member 2. In the arrangement step, the auxiliary member 10 is arranged at a position corresponding to the first metal member 1 on the surface 2b of the second metal member 2. The front surface 2b of the second metal member 2 and the back surface 10b of the auxiliary member 10 are in surface contact. In the arrangement step according to the present embodiment, the auxiliary member 10 is arranged at a position where the center of the auxiliary member 10 and the center of the first metal member 1 in the thickness direction substantially overlap.

  As shown in FIG. 2, the friction stir process is a process of inserting a rotating joining tool F rotating from the front surface 10a side of the auxiliary member 10 and friction stir welding the butt portion J1. The joining rotary tool F corresponds to a “rotating tool” in the claims. The joining rotary tool F includes a connecting portion F1 and a stirring pin F2. The connecting portion F1 is a portion to be attached to a friction stirrer (not shown), and has a columnar shape.

  The stirring pin F2 hangs down from the connecting portion F1 and is coaxial with the connecting portion F1. The stirring pin F2 tapers as it moves away from the connecting portion F1. A spiral groove is engraved on the outer peripheral surface of the stirring pin F2. In this embodiment, in order to rotate the joining rotary tool F clockwise, the spiral groove is formed counterclockwise from the base end toward the tip.

  In addition, when rotating the joining rotary tool F counterclockwise, it is preferable to form the spiral groove clockwise from the base end toward the tip end. By setting the spiral groove in this way, the metal plastically fluidized at the time of friction stirring is guided to the tip side of the stirring pin F2 by the spiral groove. Thereby, the amount of the metal overflowing to the outside of the metal members to be joined (the first metal member 1, the second metal member 2, and the auxiliary member 10) can be reduced.

  In the friction stir process, the stirring pin F2 rotated clockwise from the surface 10a of the auxiliary member 10 is inserted. In the friction stir process, the first metal member 1, the second metal member 2, and the auxiliary member 10 are brought into contact with each other with the stirring pin F2 being in contact with the first metal member 1, the second metal member 2, and the auxiliary member 10 along the butting portion J1 from the near side to the far side in FIG. The rotating tool F is relatively moved. In the friction stir process, friction stir is performed with the base end side of the stirring pin F2 exposed. The rotation center axis C of the joining rotary tool F is set at a position passing through the center of the first metal member 1 in the thickness direction. A plasticizing region W1 is formed on the movement trajectory of the joining rotary tool F. The insertion depth of the stirring pin F2 may be appropriately set, but in the present embodiment, the stirring pin F2 is set so as to be in contact with the first metal member 1.

  In the friction stir process, friction stir welding may be performed by bringing only the stirring pin F2 into contact with only the second metal member 2 and the auxiliary member 10. In this case, the butted portion J1 is plastically fluidized by friction heat between the second metal member 2 and the stirring pin F2, and is joined. A burr V is formed on the surface 10a of the auxiliary member 10.

  The removing step is a step of removing the auxiliary member 10 from the second metal member 2 as shown in FIG. In the removing step, the auxiliary member 10 is cut off while being bent at the groove D while turning up both ends of the auxiliary member 10. The concave groove D is a part of the plasticized region W1 that is deeply recessed. The removing step may use a cutting tool or the like, but in the present embodiment, the removing step is performed manually. Through the above steps, the first metal member 1 and the second metal member 2 are joined in a T-shape in a front view.

  According to the joining method according to the embodiment described above, only the stirring pin F2 is brought into contact with the first metal member 1, the second metal member 2 and the auxiliary member 10, or the second metal member 2 and the auxiliary member 10. Since the friction stir welding is performed in the closed state, the load on the friction stirrer can be reduced as compared with the related art. Thereby, even when the plate thickness of the second metal member 2 is large, it is possible to join the butt portion J1 at a deep position without applying a large load to the friction stirrer.

  Further, since only the stirring pin F2 is inserted, the width of the plasticized region W1 can be reduced. Thereby, the plate thickness of the first metal member 1 can be reduced, so that the degree of freedom in designing the first metal member 1 can be increased. Further, in addition to the first metal member 1 and the second metal member 2, the auxiliary member 10 is also subjected to friction stir welding, so that it is possible to prevent a shortage of metal at the joint (plasticized region W1) as shown in FIG. 4. .

  In addition, according to the removing step, the burrs V can be removed together with the auxiliary member 10, so that the surface 2 b of the second metal member 2 can be finely finished without separately performing an operation of removing burrs. In addition, in the friction stir process of the present embodiment, since the joining rotary tool F is inserted from the center of the surface 10a of the auxiliary member 10, the inserting operation of the joining rotary tool F can be easily performed.

[Second embodiment]
Next, a joining method according to a second embodiment of the present invention will be described. In the joining method according to the second embodiment, a butting step, an arrangement step, a friction stir step, and a removing step are performed. The joining method according to the second embodiment differs from the first embodiment in the position of the auxiliary member 10. In the joining method according to the second embodiment, a description will be given mainly of a portion different from the first embodiment.

  In the butting step, as shown in FIG. 5, the end surface 1a of the first metal member 1 and the back surface 2c of the second metal member 2 are butted as in the first embodiment to form a butted portion J1.

  Here, as shown in FIG. 5, in the friction stir process, a scheduled position through which the rotation center axis C (see FIG. 6) of the welding rotary tool F passes is set as a "welding reference line X". In the present embodiment, the joining reference line X is set so as to overlap the center of the first metal member 1 in the thickness direction. In the disposing step, the auxiliary member 10 is arranged on the surface 2b of the second metal member 2 on only one side with respect to the joining reference line X, and the side surface 10c of the auxiliary member 10 is located at a position overlapping the joining reference line X. 10 is arranged. In addition, the welding reference line X is a position where the plastic fluid does not flow out from the inner corners of the side surfaces 1b and 1c of the first metal member 1 and the back surface 2c of the second metal member 2 in the friction stir process described later. What is necessary is just to set suitably.

  In the friction stir process, as shown in FIG. 6, the rotation center axis C of the welding rotary tool F rotated right is inserted into a position overlapping with the welding reference line X, and the welding is performed from the near side to the far side in FIG. Is a step of relatively moving the rotary tool F for friction stir welding of the butted portion J1. In the friction stir step, as in the first embodiment, only the stirring pin F2 of the joining rotary tool F is brought into contact with the first metal member 1, the second metal member 2 and the auxiliary member 10, or The friction stir welding is performed in a state where the friction stir welding is in contact with the second member 2 and the auxiliary member 10.

  In this embodiment, the auxiliary member 10 of the second metal member 2 is disposed on the shear side (advancing side: the side on which the moving speed of the rotary tool is added to the tangential speed on the outer periphery of the rotary tool) of the rotary tool F for joining. The moving direction and the rotating direction of the joining rotary tool F are set so as to be on the side that is not connected. The rotation direction and the traveling direction of the joining rotary tool F are not limited to those described above, and may be set as appropriate.

  For example, when the rotational speed of the joining rotary tool F is low, the shear flow is more plastic on the shear side than on the retreating side (the side on which the moving speed of the rotary tool is subtracted from the tangential speed on the outer periphery of the rotary tool). Since the temperature of the material tends to rise, a large amount of burrs V tend to be generated on the shear side outside the plasticized region W1. On the other hand, for example, when the rotational speed of the joining rotary tool F is high, although the temperature of the plastic fluid material rises on the shear side, the burr V increases on the flow side outside the plasticizing region W1 due to the high rotational speed. Tends to occur.

  In the present embodiment, since the rotation speed of the joining rotary tool F is set to be high, a large amount of burrs V tend to occur on the flow side outside the plasticizing region W1, as shown in FIG. Further, by setting the rotation speed of the joining rotary tool F to be high, the moving speed (feeding speed) of the joining rotary tool F can be increased. Thereby, the joining cycle can be shortened.

  At the time of the friction stir step, on which side of the traveling direction of the welding rotary tool F the burr V is generated depends on the welding conditions. The welding conditions include the rotation speed, the rotation direction, the moving speed (feed speed), the inclination angle (taper angle) of the stirring pin F2, the metal members to be welded (the first metal member 1, the second metal member). It is determined by each element such as the material of the member 2 and the auxiliary member 10), the thickness of the metal member to be joined, and the combination of these elements. It is preferable to set the auxiliary member 10 on the side where the burr V is generated or on the side where a large amount of burr V is generated, according to the joining conditions, since the removal step described later can be easily performed.

  The removing step is a step of removing the auxiliary member 10 from the second metal member 2. In the removing step, the auxiliary member 10 is removed by bending, as in the first embodiment. Through the above steps, the first metal member 1 and the second metal member 2 are joined.

  With the bonding method according to the second embodiment described above, substantially the same effects as in the first embodiment can be achieved. In addition, in the arrangement step according to the second embodiment, the auxiliary member 10 was arranged on one side with respect to the joining reference line X, and in the friction stir step, the joining conditions were set such that burrs V were generated on the auxiliary member 10 side. Thereby, the burrs V can be concentrated on the auxiliary member 10 arranged on one side with respect to the joining reference line X. Thereby, since the burrs V can be removed together with the auxiliary member 10, the burrs V can be easily removed.

[Third embodiment]
Next, a joining method according to a third embodiment of the present invention will be described. In the joining method according to the third embodiment, a butting step, an arrangement step, a friction stir step, and a removing step are performed. In the joining method according to the third embodiment, a description will be given focusing on portions different from the first embodiment.

  In the butting step, as shown in FIG. 8, the end face 1a of the first metal member 1 and the back surface 2c of the second metal member 2 are butted as in the first embodiment to form a butted portion J1. Also in the present embodiment, the joining reference line X is set at a position overlapping the center of the first metal member 1 in the plate thickness direction. In the disposing step, the side surface 10c of the auxiliary member 10 is slightly shifted to one side with respect to the bonding reference line X while the auxiliary member 10 is disposed on the surface 2b of the second metal member 2 on the other side with respect to the bonding reference line X. The auxiliary member 10 is arranged so as to protrude. The thickness of the auxiliary member 10 and the distance from the joining reference line X to the side surface 10c are determined so that in the friction stir processing described later, no metal shortage occurs in the joint (plasticized region W1), and one side after the friction stirring step. Is set appropriately so that the auxiliary member 10 does not remain.

  In the friction stir process, as shown in FIG. 9, the rotation center axis C of the welding rotary tool F rotated left is inserted into a position overlapping with the welding reference line X, and welding is performed from the near side to the far side in FIG. Is a step of relatively moving the rotary tool F for friction stir welding of the butted portion J1. In the friction stir step, as in the first embodiment, only the stirring pin F2 of the joining rotary tool F is brought into contact with the first metal member 1, the second metal member 2 and the auxiliary member 10, or The friction stir welding is performed in a state where the friction stir welding is in contact with the second member 2 and the auxiliary member 10.

  In the present embodiment, since the joining rotary tool F is rotated to the left, burrs V tend to be formed on the flow side of the auxiliary member 10.

  The removal step is a step of removing the auxiliary member 10 from the second metal member 2 as shown in FIG. In the removing step, the auxiliary member 10 is bent to remove the auxiliary member 10 from the second metal member 2.

  According to the bonding method according to the third embodiment described above, substantially the same effects as in the first embodiment can be obtained. Further, according to the present embodiment, in the arranging step, the auxiliary member 10 is arranged on the other side with respect to the joining reference line X, and the side surface 10c of the auxiliary member 10 is slightly projected on one side. In the friction stir process, the auxiliary member 10 and the burr V do not remain on one side of the surface 2b of the second metal member 2 while the butting portion J1 is friction stir welded, and the burr V is generated on the auxiliary member 10 side. Is set as follows. This makes it possible to prevent a shortage of metal in the joint (plasticized region W1) in a well-balanced manner, and to concentrate the burrs V on the auxiliary member 10 arranged on the other side. Thereby, since the burrs V can be removed together with the auxiliary member 10, the burrs V can be easily removed.

  Although the embodiments of the present invention have been described above, design changes can be made as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 1st metal member 2 2nd metal member 10 auxiliary member F rotating tool F1 connection part F2 stirring pin J1 butting part W1 plasticization area

Claims (2)

A joining method of joining the first metal member and the second metal member using a rotating tool having a stirring pin,
A butting step of forming a butting portion by abutting an end surface of the first metal member and a back surface of the second metal member,
An arranging step of arranging an auxiliary member at a position corresponding to the first metal member on the surface of the second metal member,
The stirring pin rotating inserted from the surface side of the auxiliary member, only the stirring pin, said second metal member and the auxiliary member, or the first metal member, said second metal member and the auxiliary member A friction stir step of relatively moving the rotary tool in a contact state and friction stir welding the butted portion;
A removal step of removing the auxiliary member which burrs are formed from the second metal member, only containing,
At the time of the friction stir step, when a predetermined position through which the rotation center axis of the rotating tool passes is set as a welding reference line,
In the arranging step, the auxiliary member is arranged only on one side with respect to the joining reference line,
In the friction stirring step, a joining condition is set such that the burr is generated on the auxiliary member . A joining method of joining the first metal member and the second metal member using a rotating tool having a stirring pin,
A butting step of forming a butting portion by abutting an end surface of the first metal member and a back surface of the second metal member,
An arranging step of arranging an auxiliary member at a position corresponding to the first metal member on the surface of the second metal member,
The stirring pin rotating inserted from the surface side of the auxiliary member, only the stirring pin, said second metal member and the auxiliary member, or the first metal member, said second metal member and the auxiliary member A friction stir step of relatively moving the rotary tool in a contact state and friction stir welding the butted portion;
A removal step of removing the auxiliary member which burrs are formed from the second metal member, only containing,
At the time of the friction stir step, when a predetermined position through which the rotation center axis of the rotating tool passes is set as a welding reference line,
In the disposing step and the friction stirring step, the auxiliary member is disposed so as to straddle the joining reference line,
The burrs are generated on the auxiliary member on one side with respect to the bonding reference line, and the arrangement position and the bonding conditions of the auxiliary member are set so that the auxiliary member does not remain on the other side after the friction stir process. A joining method characterized by the above-mentioned.

Images