JP4542795B2 - Friction stir welding method and its jig - Google Patents

Description

  The present invention relates to a friction stir welding method and a jig for joining a laminated portion formed by laminating a plurality of members.

  As a method of laminating members and joining the laminated portions, spot welding is common, but in recent years, joining by friction stir welding has been proposed. As such a friction stir welding apparatus that performs friction stir welding of a part, for example, the one described in Patent Document 1 can be cited.

  By the way, in the friction stir welding, the flesh of the member is plastically flowed by burying the probe of the friction stir welding tool that rotates. For this reason, when friction stir welding is performed with the apparatus illustrated in FIG. 1 of Patent Document 1, since the receiving portion on which the stacked portion is placed is flat, the probe is buried from the upper end surface side of the stacked portion, and the meat Even when plastic flow occurs, the meat cannot protrude from the lower end surface side. That is, even if the probe is buried, the meat does not flow because there is no flow destination of the meat, so that the meat for which the probe is buried flows out as burrs on the upper end surface side. Therefore, a finishing process for cutting burrs is required. Further, as shown in FIG. 8, the thickness T3 of the portion crushed as the probe 8 is buried, and the thickness T4 of the workpiece W2 immediately above the portion where the lower workpiece W1 is raised in the vicinity of the buried portion are obtained. Since it becomes small, the malfunction that the joining strength of the laminated part 6 becomes insufficient is caused.

  Therefore, as shown in FIG. 9, it is recalled that the mounting jig 2 provided with the recess 1 is inserted into the insertion recess 4 of the support jig 3 to form the friction stir welding jig 5. If the laminated portion 6 of the first workpiece W1 and the second workpiece W2 is placed on the concave portion 1 of the placement jig 2 and the probe 8 of the friction stir welding tool 7 is buried, the meat in the region A is softened. Then, it plastically flows, and finally the meat flows into the recess 1. In this way, since the meat in which the probe 8 is buried flows into the recess 1, the occurrence of burrs is suppressed, and the plastically-flowed meat protrudes toward the lower end surface, so the laminated portion 6 after joining It is presumed that the bonding strength can be ensured because the wall thickness of the film does not become small.

JP 2002-178168 A

  However, even if the friction stir welding jig 5 shown in FIG. 9 is used, it may be difficult to say that the bonding strength is sufficient. The reason for this is that, as shown in FIG. 10, an axis L1 passing through the central portion of the recess 1 provided in the mounting jig 2 and an axis L2 passing through the central portion of the friction stir welding tool 7 (probe 8). This is because it is not easy to match.

  When the friction stir welding is continued in a state where the axis L1 and the axis L2 do not coincide with each other, that is, in a state where so-called misalignment occurs, as shown in FIG. 9, the side peripheral wall of the probe 8 and the inner peripheral wall of the recess 1 A region B1 in which the interval is increased and a region B2 in which the interval is decreased are formed. In this case, the meat is well agitated in the region B2 where the distance between the side peripheral wall of the probe 8 and the inner peripheral wall of the recess 1 is small, but the amount of meat to be agitated decreases in the region B1 where the distance is large. The degree of joining is not sufficient. As a result, it is inferred that the bonding strength is reduced.

  In order to solve such a problem, so-called centering is performed in advance so that the axis line L1 and the axis line L2 are matched as much as possible. However, centering is a complicated operation that requires accuracy, and when the misalignment occurs due to some disturbance after the centering operation is completed, the centering operation must be performed again. For this reason, the malfunction that the working efficiency of friction stir welding falls will be obvious.

  The present invention has been made to solve the above-described problems, and improves the working efficiency of friction stir welding and further improves the joint strength of the joint without complicating the configuration of the friction stir welding apparatus. It aims at providing the stir welding method and its jig | tool.

In order to achieve the above object, according to the present invention, a laminated portion formed by laminating a plurality of members is inserted so that a clearance is generated in an insertion recess of a support jig and is formed on an upper end surface. A friction stir welding method for supporting by a mounting jig provided with a recess, burying a probe of a friction stir welding tool from the upper end surface of the laminated portion and friction stir welding the laminated portion,
When friction stir welding the laminated portion on while rotating operation to obscure directed into the recess before described jig from the upper end surface of the laminated portion recess and said probe, said mounting jig, the The mounting jig is displaced in the insertion recess in a direction in which the center of the recess of the mounting jig and the center of the probe coincide with each other.

  In the present invention, by burying the probe in the laminated portion, the center portion of the probe and the center portion of the mounting jig are made to coincide with each other. In other words, centering is performed when the probe is buried. For this reason, it is not necessary to perform complicated centering in advance. Therefore, the working efficiency of friction stir welding is improved.

  Moreover, by performing friction stir welding as described above, the meat of the laminated portion existing around the probe is equally stirred regardless of the portion. That is, since there is no part where the amount of meat to be stirred is small, there is no part where the bonding strength is low. Thereby, a lamination | stacking part with large joining strength can be obtained.

  In this case, as the probe is buried, a state in which the stacked workpieces are coupled to each other at the protruding portion and the depressed portion, that is, a so-called caulking state is formed. This also increases the bonding strength of the laminated portion.

  Furthermore, according to the present invention, since the meat is plastically flowed into the recess of the mounting jig, it is possible to avoid the formation of burrs.

The present invention is also a friction stir welding jig for friction stir welding a laminated portion formed by laminating a plurality of members,
A placing jig provided with a recess on the upper end surface for placing the laminated portion;
A support jig provided with a recess for insertion for inserting the placement jig;
And the insertion recess of the support jig, and an elastic body interposed between one portion of pre-described jig that is inserted into the insertion recessed portion,
I have a,
The one part of the front according jig, wherein the inserted Rukoto such clearance is formed between the inner wall of the insertion recess of the support jig.

  With such a configuration, when the probe is buried in the stacked portion, the center portion of the probe and the center portion of the mounting jig can be aligned to perform centering. Therefore, as described above, it is possible to improve the working efficiency of the friction stir welding and obtain a laminated portion having excellent bonding strength.

  Moreover, since the mounting jig is freely displaceable in the insertion concave portion by interposing an elastic body, the friction stir welding jig is adapted to displace the mounting jig in the insertion concave portion. The configuration of the system is not complicated. That is, the friction stir welding jig can have a simple configuration.

  According to the present invention, when the concave portion is provided in the mounting jig for mounting the stacked portion formed by stacking the workpieces, and the probe of the friction stir welding tool is embedded in the stacked portion, The mounting jig is displaced in a direction in which the central portion of the concave portion and the central portion of the probe coincide. For this reason, it is not necessary to perform complicated centering in advance.

  In the present invention, since the friction stir welding proceeds in a state where the center portion of the recess and the center portion of the probe substantially coincide with each other, the meat of the laminated portion existing around the probe is equally stirred regardless of the portion. The For this reason, the effect that a friction stir welding part with high joining strength can be obtained is achieved.

  Hereinafter, preferred embodiments of the friction stir welding method according to the present invention will be described in detail in relation to the friction stir welding jig used therein and will be described in detail with reference to the accompanying drawings.

  FIG. 1 shows an enlarged schematic perspective view of a main part of the friction stir welding jig according to the present embodiment. The friction stir welding jig 10 includes a support jig 14 provided with an insertion recess 12 shown in FIG. 2 and a mounting jig 16 inserted into the insertion recess 12.

  In this case, the shape of the support jig 14 is a substantially rectangular parallelepiped, and the insertion recess 12 is provided at a substantially central portion of the upper end surface of the support jig 14. As can be seen from FIG. 3, the insertion recess 12 has two parallel long side portions and two short side portions orthogonal to the long side portion in the horizontal cross section, and the long side portion. An arc portion is interposed between the short side portion and the short side portion.

  As shown in FIG. 2, the mounting jig 16 has a horizontal cross-section similar to the insertion recess 12 and a slightly smaller dimension than the insertion recess 12. Compared with the flange portion 20 and the mounting portion 22, the protruding portion 18 is inserted into the insertion recess 12, while the lower end surface of the flange portion 20 is the support jig 14. It is in contact with the upper end surface. The placement jig 16 is blocked by this contact. Since the protrusion 18 is slightly smaller than the insertion recess 12, a clearance 24 is generated between the inner peripheral wall of the insertion recess 12 and the side peripheral wall of the protrusion 18.

  In addition, annular grooves 26 and 28 are provided in the inner peripheral wall of the insertion recess 12 and the side peripheral wall of the protrusion 18, respectively. In these annular grooves 26 and 28, rubber O as an elastic body is provided. A ring 30 is inserted. In other words, the inner peripheral wall of the insertion recess 12 and the side peripheral wall of the protrusion 18 in the mounting jig 16 are slightly separated from each other with the O-ring 30 interposed.

  The upper end surface of the mounting portion 22 is provided with a hollow cylindrical body-shaped concave portion 32 having a substantially circular horizontal cross section (see FIG. 1).

  As will be described later, the concave portion 32 of the mounting portion 22 is covered with a stacked portion 6 formed by stacking the first workpiece W1 and the second workpiece W2. In the present embodiment, the first workpiece W1 and the second workpiece W2 are made of so-called 5000 series aluminum whose number of JIS symbols is in the 5000 range. The first workpiece W1 and the second workpiece W2 are respectively supported by a support base (not shown) arranged in the vicinity of the friction stir welding jig 10.

  The friction stir welding tool 7 includes a rotating body 34 and a probe 8 connected to one end portion of the rotating body 34 and having a tip end curved in a conical shape. The outer diameter of the probe 8 is set smaller than the diameter of the recess 32 provided in the mounting portion 22. The length L3 of the probe 8, the thickness T1 of the first workpiece W1, and the thickness T2 of the second workpiece W2 can be set to about 2.5 mm, about 1.5 mm, and about 1.0 mm, for example. .

  The friction stir welding jig 10 according to the present embodiment is basically configured as described above. Next, the function and effect of the friction stir welding jig 10 and the friction stir welding method according to the present embodiment will be described. Explain in relation.

  The friction stir welding method according to the present embodiment is performed as follows.

  First, as shown in FIG. 1, the first workpiece W <b> 1 and the second workpiece W <b> 2 are stacked to form the stacked portion 6, and the stacked portion 6 is mounted on the upper end surface of the mounting portion 22 of the mounting jig 16. Put. Thereby, the recessed part 32 is covered with the laminated part 6.

  Next, as shown in FIG. 3, the friction stir welding tool 7 (probe 8) is arranged so that its axis L <b> 2 coincides with the axis L <b> 1 of the recess 32 as much as possible. At this time, it is not particularly necessary to completely match the axis L1 and the axis L2.

  Then, after the probe 8 is lowered to a position spaced apart from the laminated portion 6 at a predetermined interval, the probe 8 is rotated and biased together with the rotating body 34. In this state, as shown in FIG. 2, the probe 8 is brought into sliding contact with the upper end surface of the laminated portion 6. By generating frictional heat along with this sliding contact, the contact portion of the probe 8 in the laminated portion 6 and the vicinity thereof are softened. As a result, as shown in FIG. 4, the probe 8 is buried in the laminated portion 6, and the meat of the laminated portion 6 flows into the concave portion 32 corresponding to the buried portion. As described above, since the diameter of the horizontal section of the recess 32 is larger than the diameter of the probe 8, this inflow easily proceeds.

  Here, when the rotating probe 8 is buried in the laminated portion 6 in a state of being misaligned and the meat flows into the concave portion 32, the mounting jig 16 has a direction perpendicular to the axis L1 or the axis L2. That is, a force directed in the horizontal direction acts. This force acts more in the direction in which the misalignment is smaller than the direction in which the misalignment is increased. Accordingly, the placement jig 16 is displaced in the horizontal direction inside the insertion recess 12 under the action of this force. As a result, finally, as shown in FIGS. 4 and 5, the axis L1 and the axis L2 coincide.

  During this displacement, the O-ring 30 that is an elastic body is deformed. That is, the O-ring 30 does not prevent the placement jig 16 from being displaced.

  That is, in the present embodiment, when the probe 8 is buried in the stacked portion 6 in a state where the axis L2 of the probe 8 does not coincide with the axis L1 of the recess 32, the mounting jig 16 has the axis L1 and the axis L2. The centering is performed by shifting in the direction in which. For this reason, it is not necessary to make the axis line L1 and the axis line L2 coincide with each other accurately when the probe 8 is buried. In other words, it is not necessary to perform the centering, which is a complicated operation, before performing the friction stir welding. For this reason, the working efficiency of friction stir welding improves.

  In addition, in this case, since the probe 8 is buried in the stacked portion 6 in a state where the axis L1 and the axis L2 substantially coincide with each other, the probe 8 is approximately centered on the recess 32 with a certain distance from the inner peripheral wall of the recess 32. Inserted into the section. Therefore, a region with a small interval and a region with a large interval are not formed between the side peripheral wall of the probe 8 and the inner peripheral wall of the recess 32. For this reason, the meat (stirring area A) around the probe 8 is stirred equally, and as a result, the degree of friction stir welding in the meat becomes the same regardless of the part. That is, since there is no part where the amount of meat to be stirred is small, there is no part where the bonding strength is small. For this reason, the bonding strength of the laminated portion 6 can be increased.

  Further, since the meat of the laminated portion 6 flows into the recess 32, the meat at the contact portion can be agitated in a large amount.

  Further, as the probe 8 is buried, a protruding portion 36 is formed on the surface of the second workpiece W2 facing the first workpiece W1, and a depressed portion 38 is formed on the surface of the first workpiece W1 facing the second workpiece W2. Then, the protruding portion 36 is fitted into the depressed portion 38. In addition, the lower end part of the depression part 38 is a non-stirring part (plastic deformation part) where plastic flow of meat is not performed. That is, the lower end portion of the depressed portion 38 is molded into a shape corresponding to the concave portion 32 by plastic deformation, and a so-called caulking state is provided. In this way, the joining strength is also improved by forming the caulking state between the first work W1 and the second work W2.

  In addition, according to the present embodiment, in the laminated portion 6, the meat in which the probe 8 is buried plastically flows into the recess 32. For this reason, since the meat does not rise, no burr is formed. Thus, by using the mounting jig 16 provided with the recess 32, the laminated portion 6 can be friction stir welded without forming burrs.

  When the mounting jig 16 tries to rotate following the rotation of the probe 8, the outer wall portion of the protrusion 18 interferes with the inner wall portion of the insertion recess 12 as shown in FIG. . For this reason, since the mounting jig 16 is prevented from rotating, the implementation of the friction stir welding is not hindered.

  In this case, if the plastic flow of the meat is stopped by detaching the probe 8 approximately 2 seconds after starting the stirring, the meat of the laminated portion 6 is finally cooled and solidified. As a result, the first workpiece W1 and the second workpiece W2 are integrally solid-phase bonded, and the friction stir welding portion 40 is formed as shown in FIG. On the side of the first workpiece W1 in the friction stir welding portion 40, there is a cylindrical convex portion 42 that protrudes as the meat flowing into the concave portion 32 cools and solidifies. That is, in this case, the outer diameter of the convex portion 42 is substantially the same as the diameter of the concave portion 32.

  In addition, the recessed part provided in the mounting part 22 is not specifically limited to the cylindrical recessed part 32. FIG. For example, a long groove shape may be used. In this case, by scanning the probe 8, a long convex portion is formed corresponding to the long groove-shaped concave portion.

  In addition, it is not particularly necessary to fill the entire space of the concave portion 32 with the meat of the laminated portion 6.

  The number of workpieces to be stacked is not limited to two, and three or more workpieces may be stacked.

It is a principal part expansion schematic perspective view which shows the friction stir welding jig | tool which concerns on this Embodiment, the 1st workpiece | work and 2nd workpiece | work which are friction stir welded, and the tool for friction stir welding. It is a partial longitudinal cross-sectional enlarged view which shows the state by which the laminated part was mounted in the mounting jig which comprises the jig | tool for friction stir welding of FIG. It is a schematic cross-sectional explanatory drawing which shows the state which the axis line of the recessed part of a mounting jig and the axis line of a probe do not correspond. It is a partial longitudinal cross-sectional enlarged view which shows the state which the axis line of the recessed part of the mounting jig and the axis line of the probe substantially corresponded with the mounting jig being displaced in the recessed part for insertion. It is a schematic cross-sectional explanatory drawing which shows the state which the axis line of the recessed part of the mounting jig | tool substantially matched with the axis line of the probe. It is a schematic cross-sectional explanatory drawing which shows the state by which rotation operation | movement of the mounting jig was blocked | prevented. It is principal part perspective explanatory drawing of the friction stir welding site | part joined by the friction stir welding method which concerns on this Embodiment. It is a partial longitudinal cross-sectional view which shows the state which is implementing the friction stir welding method which concerns on a prior art. It is a partial longitudinal cross-sectional enlarged view which shows the state which carries out the friction stir welding of the laminated part using the jig | tool for friction stir welding which a mounting jig cannot displace. FIG. 10 is a schematic cross-sectional explanatory diagram showing a state where the axis of the recess of the mounting jig of FIG. 9 and the axis of the probe do not match.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 32 ... Recessed part 2, 16 ... Mounting jig 3, 14 ... Support jig 4, 12 ... Insertion recessed part 5, 10 ... Friction stirring joining jig 6 ... Laminated part 7 ... Friction stirring joining tool 8 ... Probe 18 ... Protruding part 20 ... Flange part 22 ... Placement part 24 ... Clearance 30 ... O-ring 40 ... Friction stir welding site L1, L2 ... Axis W1, W2 ... Workpiece

Claims (2)

A laminated portion formed by laminating a plurality of members is supported by a mounting jig that is inserted so that a clearance is generated in the insertion concave portion of the support jig and has a concave portion on the upper end surface, A friction stir welding method in which a probe of a friction stir welding tool is buried from the upper end surface of the laminated portion to friction stir weld the laminated portion,
When the probe is rotated and buried in the concave portion of the mounting jig from the upper end surface of the stacking portion and the stacking portion on the concave portion is friction stir welded, the mounting jig is A friction stir welding method, comprising: displacing the insertion jig in a direction in which a central portion of the concave portion of the mounting jig coincides with a central portion of the probe. A friction stir welding jig for friction stir welding a laminated portion formed by laminating a plurality of members,
A mounting jig for mounting the laminated portion with a recess provided on the upper end surface;
A support jig provided with a recess for insertion for inserting the placement jig, and
And the insertion recess of the support jig, and an elastic body interposed between one portion of pre-described jig that is inserted into the insertion recessed portion,
I have a,
The one part of the front according jig is friction stir welding jig, wherein the inserted Rukoto such clearance is formed between the inner wall of the insertion recess of the support jig.

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