JP4998027B2 - Friction spot welding method - Google Patents

Description

  The present invention relates to a method of pressing a rotating tool from one side of a plurality of metal members stacked and joining the metal members with frictional heat generated thereby.

  Conventionally, aluminum alloy materials have been widely used as body materials for automobiles and the like in order to reduce the weight for the purpose of improving the fuel consumption of automobiles. Along with this, there are increasing opportunities to join a member made of, for example, an aluminum alloy and a member made of an iron material or the like.

  However, when metal members made of such dissimilar materials are joined together by fusion welding such as arc welding, there is a problem that a brittle intermetallic compound is generated and joint strength is lowered. For this reason, mechanical joining methods using rivets and the like have been used in the past. However, such methods have a problem in that the cost is increased because secondary materials such as rivets are required.

  Therefore, a joining method called friction spot joining has been developed as a method for joining metal members made of different materials at low cost. This joining method is disclosed, for example, in Patent Document 1 below, and as shown in FIG. 1, the aluminum alloy plate 10 and the steel plate 12 are overlapped, and the tip of the rotary tool 16 is pushed into the overlapped portion. The aluminum alloy plate 10 and the steel plate 12 are solid-phase bonded at a temperature equal to or lower than the melting point by softening and plastically flowing the aluminum alloy plate 10 with frictional heat generated by the rotating operation and pressurizing operation of the rotating tool 16. To do.

Here, in particular, when joining metal members made of different materials as described above, if water or the like is mixed between the metal members, at least one of the metal members may be corroded due to a potential difference between these members. There is. Therefore, when joining metal members of different materials in this way, a method of interposing a fluid insulating material 14 between these members is considered in order to avoid the electrolytic corrosion.
JP 2005-34879 A

  However, as shown in FIG. 1, if the insulating material 14 is simply interposed between the metal members 10, 12 and the rotary tool 16 is pushed into the metal member 10, the insulating material is pressed by the rotary tool 16. 14 is pushed out from the joint portion P, and the aluminum alloy plate 10 is thermally deformed by applying frictional heat to the aluminum alloy plate 10 by the rotating tool 16, as shown in FIG. There is a possibility that a gap S is formed between the metal members 10 and 12 so that the insulating material 14 does not intervene and the metal members 10 and 12 are not sufficiently insulated from each other.

  This invention is made | formed in view of the above situations, and it aims at provision of the friction point joining method which can join metal materials, suppressing the heat deformation of a metal material more reliably.

The invention according to claim 1 for solving the above-mentioned problem is a method of superimposing a first metal member and a second metal member and joining the two metal members in a solid state, the first metal member As the second metal member, a metal member provided with a rigid portion for increasing the rigidity in the vicinity of the bonded portion at a position surrounding the bonded portion to be bonded in a solid phase is used. A preparatory step of superimposing the two metal members in a state where an insulating adhesive is interposed between the one metal member and the second metal member; and a rotating tool is brought into contact with the bonded portion of the first metal member A joining step of joining the two metal members in a solid state by softening and plastically flowing a joined portion of the first metal member with frictional heat generated by the rotational operation and pressurizing operation of the rotary tool; Solid state of both metal members With a portion other than the joint portion and a bonding step of bonding by the adhesive, as the first metal member, spaced from the second metal member from the surface of the first metal member to a position surrounding the joint target a metal member having a bead portion is formed protruding in a direction, constitutes the rigid portion by the bead portion at the joining step, constituting the rigid portion the deformation of the first metal member by the frictional heat The friction point joining method is characterized by joining the two metal members in a solid phase state to the joined portion of the first metal member and the second metal member while being suppressed by the bead portion. Item 1).

  According to the present invention, the first metal member and the second metal member are solid-phase bonded by frictional heat of the rotary tool, and an adhesive is interposed between the first metal member and the second metal member. Thus, since the portion other than the joint portion in the solid phase is adhered by the adhesive, the joint strength between the first metal member and the second metal member can be ensured. In addition, as the first metal member, a metal member having a rigid portion and having increased rigidity around the bonded portion with which the rotating tool is brought into contact with the rigid portion is used. Can be prevented from being largely thermally deformed by frictional heat generated by the rotating tool. As a result, it is possible to effectively avoid the formation of a gap in which no adhesive is interposed between the two metals, and the adhesive is interposed between the two metal members excluding the bonded portion in the solid phase. Therefore, the bonding strength of these metal members can be ensured. In particular, when the first metal member and the second metal member are made of different materials, it is possible to more reliably prevent the metal member from being eroded by water entering the gap. become.

Further, when the present invention is used to join the first metal member, which is a plate material made of aluminum alloy, and the second metal member, which is a plate material made of steel, both of them can be controlled while suppressing electrolytic corrosion due to a potential difference between these different materials. The metal members can be joined more reliably, which is effective (claim 2 ).

Further, the present invention is a method of superimposing a first metal member and a second metal member and joining the two metal members in a solid phase state, wherein the second metal member and a solid phase are used as the first metal member. A metal member provided with a rigid portion for increasing the rigidity in the vicinity of the bonded portion at a position surrounding the bonded portion to be bonded in a state, the first metal member having the rigid portion, and the second metal member, A preparatory step in which the two metal members are overlapped with an insulating adhesive interposed therebetween, and a rotating tool abutting on the bonded portion of the first metal member, and the rotating operation and addition of the rotating tool. A joining step of joining the two metal members in a solid state by softening and plastically flowing a portion to be joined of the first metal member by frictional heat generated by pressure operation; and in a solid state of the two metal members Bonding the parts other than the joint part Together and a bonding step of bonding by, at the preparation step, wherein an adhesive bonded to the該被joint portion of the second metal member and the portion other than the joint target of said first metal member The metal member is interposed between portions other than the joint portion to be joined, and in the joining step, the two metal members are joined while the deformation of the first metal member due to the frictional heat is suppressed by the rigid portion. Including a friction point joining method .

  In this way, when frictional heat is applied to the first metal member by the rotary tool, the frictional heat can be prevented from being taken away by the adhesive, and both metal members can be solid-phase bonded. Therefore, it is possible to reduce the energy to be input, which is advantageous in terms of cost.

  As described above, according to the present invention, in the friction point joining method for joining a plurality of metal members, thermal deformation of the metal members can be suppressed to ensure the joining strength.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, the outline | summary of the friction point joining apparatus 1 used in order to implement the friction point joining method concerning this invention is demonstrated.

  FIG. 3 is a diagram schematically illustrating an example of the friction point welding apparatus 1. The friction point joining apparatus 1 shown in FIG. 3 is an apparatus for joining an aluminum alloy plate 20 (first metal member), a steel plate 30 (corresponding to a second metal member), and the like. It has the rotary tool 16 pressed against the to-be-joined part P1 of the aluminum alloy plate 20 in the state where the steel plate 30 is overlapped as shown. The rotary tool 16 is formed of a substantially cylindrical member that is driven to rotate about a central axis X, and is pressed against the joined portion P1 of the aluminum alloy plate 20 having a low melting point, of the aluminum alloy plate 20 and the steel plate 30. The friction spot welding device 1 is configured to generate frictional heat by pushing the rotary tool 16 into the joined portion P1 while rotating the rotary tool 16 at a high speed, and to join the metal members 22 and 30 to each other by the frictional heat. Has been. Hereinafter, the aluminum alloy plate 20 is simply referred to as an aluminum plate 20.

  In FIG. 4, the front-end | tip part of the said rotation tool 16 is expanded and shown. In FIG. 4, the left half shows the cross section of the rotary tool 16, and the right half shows the outer shape. As shown in FIG. 4, the distal end portion (lower end portion in the figure) of the rotary tool 16 has a small-diameter cylindrical pin portion 16a projecting from the center portion thereof, and a portion radially outward from the pin portion 16a. And a shoulder portion 16b formed so that the height of the bottom surface becomes lower toward the outside. The pin portion 16a is formed such that a lower end portion thereof protrudes a predetermined distance below the height of the peripheral edge portion of the shoulder portion 16b.

  The specific dimensions of the rotary tool 16 are appropriately determined depending on the thickness of the aluminum plate 20 and the steel plate 30. As an example of a preferable value, the diameter D1 of the shoulder portion 16b is 10 mm, and the pin portion 16a. Diameter D2 is 2 mm, the protrusion length h of the pin portion 16a with respect to the peripheral portion of the shoulder portion 16b is 0.3 to 0.35 mm, and the inclination angle θ (shoulder inclination angle) of the bottom surface of the shoulder portion 16b is 5 ° to 7 °. It is said.

  On the opposite side of the rotary tool 16 with the aluminum plate 20 and the steel plate 30 in between, a receiving member 17 having the same diameter or larger diameter than the rotary tool 16 is coaxially arranged. The receiving member 17 moves in a direction approaching the rotary tool 16 (arrow A3) with the aluminum plate 20 and the steel plate 30 interposed therebetween, and at least the tip thereof abuts on the steel plate 30 until pressing by the rotary tool 16 is started. . The aluminum plate 20 and the steel plate 30 are supported against the pressing force when pressed by the rotary tool 16.

  The rotating tool 16 and the receiving tool 17 as described above are mounted on a drive control device (not shown) composed of an articulated robot or the like so that the rotation speed, pressing position, pressing force, pressing time, and the like are appropriately controlled. It is configured. Although not shown in FIG. 3, in order to prevent the aluminum plate 20 from being lifted when the aluminum plate 20 and the steel plate 30 are fixed in advance and the rotary tool 16 is pressed, a jig such as a spacer or a lift prevention plate is used. Used as appropriate.

  Next, a first embodiment according to the friction spot welding method of the present invention performed using the friction spot welding apparatus 1 as described above will be described. In this embodiment, as shown in FIGS. 3 and 5, as the aluminum plate 20, a plate material having a first recess 22 that is recessed from the surface 26 in a predetermined direction is used. The first recess 22 is formed by pressing the surface 26 of the aluminum plate 20. Specifically, the first concave portion 22 includes a first bottom surface portion 22a extending in a direction substantially parallel to the surface 26 of the aluminum plate 20, and an outer periphery of the first bottom surface portion 22a to the surface 26 of the aluminum plate 20. And a first outer peripheral wall 24 extending toward the front.

  In order to join such an aluminum plate 20 and the steel plate 30, first, as shown in FIG. 5, an insulating adhesive 40 is applied to the surface of the steel plate 30. As the adhesive 40, an adhesive having fluidity that can be easily applied to the steel sheet 30 and is cured at a temperature equal to or higher than normal temperature is used. For example, a thermosetting adhesive made of an epoxy resin and having a curing condition of 150 ° C./20 min and having a viscosity of about 170 Pa · s and a tensile shear adhesive strength of about 17.8 MPa can be mentioned.

  Next, as shown in FIG. 6, the aluminum plate 20 is overlaid on the steel plate 30 to which the adhesive 40 is applied. At this time, the aluminum plate 20 is placed so that the first recess 22 is recessed from the surface 26 of the aluminum plate 20 toward the steel plate 30 side. Moreover, the aluminum plate 20 is pressed to the steel plate 30 side, the adhesive 40 between the 1st bottom face part 22a (to-be-joined part P1) of the 1st recessed part 22 and the steel plate 30 is extruded outside, This 1st bottom face part. Overlap so that 22a directly contacts the steel plate 30. Thereby, it will be in the state where adhesive 40 intervened between portions other than the 1st bottom face part 22a of the 1st crevice 22 among the aluminum plates 20, and steel plate 30 (preparation process).

  Next, as shown in FIG. 3, while rotating the rotary tool 16 around the axis (in the direction of arrow A1), the rotary tool 16 is brought close to the aluminum plate 20 as indicated by arrow A2, and the lower end of the rotary tool 16 is moved to the aluminum plate. It is made to contact | abut to the 1st bottom face part 22a of the 1st recessed part 22 of the board 20. FIG. In accordance with this, the support 17 is brought close to the steel plate 30 as indicated by an arrow A3, and the aluminum plate 20 and the steel plate 30 are supported by being sandwiched between the rotary tools.

  Then, as described above, the rotary tool 16 that rotates at high speed with the aluminum plate 20 and the steel plate 30 sandwiched between the rotary tool 16 and the receiving member 17 is placed on the first bottom surface portion 22a of the first recess 22. The first bottom surface portion 22a and the steel plate 30 are joined by pressing to a predetermined depth and the frictional heat generated accordingly (joining step). More specifically, this joining process is divided into three processes, a first pressing process, a second pressing process, and a third pressing worker described below.

  First, in the first pressing step, as shown in FIG. 7, while the rotary tool 16 is rotated at a preset first rotational speed, the aluminum plate 20 is pressed with a first pressurizing force during a first pressurizing time. The first recess 22 is pressed against the first bottom surface 22a. The values of the first rotation speed, the first pressurizing time, and the first pressurizing force are determined based on whether the depth of pushing the rotary tool 16 against the first bottom surface portion 22a of the first recess 22 is the tip of the pin portion 16a. The peripheral portion of the shoulder portion 16b is in contact with the first bottom surface portion 22a of the first concave portion 22, while the radially inner region of the shoulder portion 16b is determined to have a depth that does not contact the first bottom surface portion 22a. Is done. Specifically, for example, the first rotation speed is set to 1500 rpm to 3500 rpm, the first pressurization time is set to 0.2 seconds to 2.0 seconds, and the first pressure is set to 2.45 kN to 3.43 kN. It is preferable.

  As described above, when the rotary tool 16 rotates around the central axis X and presses against the first bottom surface portion 22a of the first recess 22, the lower end portion of the pin portion 16a and the peripheral portion of the shoulder portion 16b in the rotary tool 16 are contacted. The frictional heat is generated between the two contact sites and the first bottom surface portion 22 a of the first recess 22. The frictional heat is quickly diffused throughout the first bottom surface portion 22a of the first recess 22 including the portion between the two contact portions (the portion where the bottom surface of the shoulder portion 16b is not in contact), The entire first bottom surface portion 22a is quickly softened. Here, since the adhesive 40 is not interposed between the first bottom surface portion 22 a and the steel plate 30, the frictional heat is prevented from being taken away by the adhesive 40. Therefore, frictional heat can be effectively applied to the first bottom surface portion 22a, and the aluminum alloy of the first bottom surface portion 22a can be softened with less energy. Moreover, if the first rotation speed, the first pressurizing time, and the first pressurizing force are set to the above values, the aluminum plate 20 can be favorably softened without shearing.

  Further, in the initial stage of the first pressing step, the pin portion 16a having a small diameter protruding by a predetermined length h from the peripheral edge portion of the shoulder portion 16b has a first portion of the first recess 22 before the shoulder portion 16b. By abutting against the bottom surface portion 22a, the rotary tool 16 is positioned with a small frictional resistance, and rotational runout in the direction perpendicular to the central axis X is suppressed.

  In the subsequent second pressing step, as shown in FIG. 8, the rotating tool 16 is rotated at the second rotation speed while the second pressing pressure is greater than the first pressing force during the second pressurizing time. Push into the first bottom surface 22 a of the first recess 22. In this second pressing step, the pressing force is increased more than in the first pressing step, so that the pin portion 16a and the shoulder portion 16b of the rotary tool 16 are made to the first bottom surface portion 22a of the first concave portion 22. The surface gradually enters deeper, and the entire surface of the pin portion 16 a and the shoulder portion 16 b contacts the first bottom surface portion 22 a of the first recess 22. Along with this, plastic flow occurs in addition to the softening of the aluminum alloy at the first bottom surface portion 22a (this plastic flow is schematically shown by a broken line Q in the figure).

  At this time, the softened aluminum alloy is outside from the first bottom surface portion 22a of the first recess 22 which is a portion immediately below the rotary tool 16 by the bottom surface of the shoulder portion 16b inclined so as to decrease in height toward the radially outer side. Therefore, the plastic flow Q is intensively generated at the first bottom surface portion 22a. Note that an oxide film (not shown) is formed on the surface of the aluminum plate 20, but this oxide film is broken at the portion where the plastic flow Q occurs, so that a new surface of the aluminum alloy is formed on the first bottom surface portion 22a. Exposed.

  The values of the second rotational speed, the second pressurizing time, and the second pressure force are determined by the depth of the rotation of the rotary tool 16 with respect to the first bottom surface portion 22a of the first concave portion 22, the pin portion 16a and the shoulder portion. The depth is determined so that the entire surface of 16b can be in contact with the first bottom surface portion 22a and the first bottom surface portion 22a is too thin to be torn off. Specifically, for example, the second rotation speed is set to 2000 rpm to 3000 rpm, the second pressurization time is set to 1.0 second to 2.0 seconds, and the second applied pressure is set to 3.92 kN to 5.88 kN, respectively. It is preferable.

  In the subsequent third pressing step, as shown in FIG. 9, the rotating tool 16 is rotated at the third rotation speed while the third pressing force is lower than the second pressing force during the third pressurizing time. The first recess 22 is pressed against the first bottom surface 22a. In the third pressing step, the pressing force is reduced as compared with the second pressing step, so that the rotary tool 16 is not pushed deeper than the depth at the completion of the second pressing step, and at the same position as that time. The first bottom surface 22a of the first recess 22 will continue to be pressed. Thereby, it is avoided that the first bottom surface portion 22a is excessively thin and torn off, and the temperature of the first bottom surface portion 22a of the first concave portion 22 that receives the pressing force of the rotary tool 16 is set to the second pressing force. It is maintained at the same level as in the process, and good plastic flow is performed for a long time.

  As specific examples of each value of the third rotation speed, the third pressurization time, and the third pressurizing value, the third rotation speed is 1500 rpm or more and 3500 rpm or less, and the third pressurization time is 0.5 second or more and 2.5. The second applied pressure is preferably set to 0.49 kN or more and 1.47 kN or less.

  In the second pressing step and the third pressing step, a new surface of the first bottom surface portion 22a of the first concave portion 22 of the steel plate 30 and the aluminum plate 20 (new surface formed by breaking the oxide film during plastic flow). , The mating surfaces of the aluminum plate 20 and the steel plate 30 are firmly solid-phase bonded. Thus, in this embodiment, the 1st bottom face part 22a of the 1st recessed part 22 of the said aluminum plate 20 is solid-phase-bonded with the said steel plate 30 as the to-be-joined part P1.

  Here, during the first pressing process to the third pressing process, frictional heat from the rotary tool 16 is applied to the aluminum plate 20. In particular, since relatively large frictional heat is transmitted around the first bottom surface portion 22a of the first recess 22 against which the rotary tool 16 is pressed, the surrounding aluminum plate 20 tends to be thermally deformed. However, as described above, the first outer peripheral wall 24 extending toward the surface 26 of the aluminum plate 20 is formed around the first bottom surface portion 22 a of the first recess 22, and the first outer peripheral wall 24 allows the first outer peripheral wall 24 to The rigidity around the bottom surface portion 22a is sufficiently increased. Therefore, the thermal deformation of the portion around the first bottom surface portion 22a is sufficiently suppressed even when the frictional heat is applied.

  Further, in the second pressing step or the like, a high pressing force is applied to the first bottom surface portion 22a of the first recess 22 by the rotary tool 16, and the periphery of the first bottom surface portion 22a receives the pressing force and receives the adhesive 40. Try to deform while extruding. However, as described above, since the periphery of the first bottom surface portion 22a has sufficient rigidity, deformation due to the pressing force is suppressed, and extrusion of the adhesive 40 to the outside is also suppressed. . As described above, in this embodiment, even when frictional heat and pressing force are applied by the rotary tool 16, the aluminum plate 20 around the first recess 22 is hardly deformed with the steel plate 30. The state where the adhesive 40 is interposed is maintained.

  When the third pressing step is completed and the joining of the aluminum plate 20 and the steel plate 30 in the solid phase is completed, the rotary tool 16 and the receiving member 17 are separated from the aluminum plate 20 and the steel plate 30. Here, as shown in FIG. 9, the first concave portion 22 of the aluminum plate 20 is formed with burrs R protruding upward while leaving marks on the shoulder portion 16b and the pin portion 16a on the first bottom surface portion 22a. Yes. When appropriate joining is performed between the aluminum plate 20 and the steel plate 30, the burr R is formed substantially uniformly over the entire circumference with an appropriate radial thickness.

  Next, the aluminum plate 20 and the steel plate 30 are carried into a predetermined container with the adhesive 40 interposed therebetween, and hot air is applied to the adhesive 40. And the said adhesive agent 40 is hardened and the aluminum plate 20 and steel plates 30 of parts other than the junction part P in the said solid-phase state are adhere | attached (adhesion process).

  As described above, the aluminum plate 20 and the steel plate 30 are solid-phase bonded at the bonding portion P, and the portions other than the bonding portion P are bonded by the adhesive 40, so that the aluminum plate 20 and the steel plate 30 are bonded together. Are joined together.

  As described above, according to the present embodiment, the aluminum plate 20 and the steel plate 30 are solid-phase bonded by the rotary tool 16, and portions other than the bonding portion P in the solid-phase state are bonded by the adhesive 40. Therefore, the joining strength between the aluminum plate 20 and the steel plate 30 can be ensured. Moreover, the aluminum plate 20 has a rigid portion 24 for increasing the rigidity around the bonded portion P1 at a position surrounding the bonded portion P1 to be solid-phase bonded to the steel plate 30. It is suppressed that the vicinity of the joining portion P1 is largely thermally deformed by the frictional heat generated by the rotary tool 16. That is, it is possible to effectively avoid the formation of a gap between the aluminum plate 20 and the steel plate 30, and the insulation between the aluminum plate 20 and the steel plate 30 except for the portion to be solid-phase bonded. Since the adhesive 40, which is a material, can be interposed, it is possible to ensure the bonding strength between the aluminum plate 20 and the steel plate 30. In particular, when the aluminum plate 20 and the steel plate 30 of different materials are joined as in the above-described embodiment, it is possible to prevent water or the like from entering the gap, such as the aluminum plate 20 and the steel plate 30. It becomes possible to suppress electric corrosion effectively.

  Further, if the rigid portion 24 is formed by changing the shape of the aluminum plate 20 as in the embodiment, the rigid portion 24 can be easily provided on the aluminum plate 20.

  Further, as the aluminum plate 20, the aluminum plate 20 having the first concave portion 22 recessed on the steel plate 30 side is used, and the first bottom surface portion 22 a of the first concave portion 22 is used as the joined portion P 1 to be solid-phase bonded to the steel plate 30. If the bonded portion P1 and the steel plate 30 are solid-phase bonded, the first outer peripheral wall 24 extending from the first bottom surface portion 22a of the first recess 22 to the surface 26 of the aluminum plate 20 can function as a rigid portion, It is possible to easily increase the rigidity around the joined portion P1. And since the frictional heat by the said rotary tool 16 can be kept in the 1st recessed part 22, it becomes possible to suppress the thermal deformation around this 1st recessed part 22 more reliably.

  In addition, when the adhesive 40 is applied to the steel plate 30 so as to be interposed between the aluminum plate 20 and the steel plate 30 other than the joint portion P, the aluminum plate 20 and the steel plate 30 are in direct contact with each other at the joint portion P. Therefore, the aluminum plate 20 and the steel plate 30 can be efficiently solid-phase bonded with less energy by avoiding the frictional heat of the rotary tool 16 being taken away by the adhesive 40. be able to.

  Next, a second embodiment of the present invention will be described. In this embodiment, as shown in FIG. 11, a steel plate 50 having a second recess 52 is used as the steel plate. The second recess 52 is recessed in a direction away from the aluminum plate 20 from the surface 56 of the steel plate 50, and extends in a direction substantially parallel to the surface 56 of the steel plate 50, and the second bottom surface portion 52a. And a second outer peripheral wall 54 extending from the outer periphery toward the surface 56 of the steel plate 50. The second outer peripheral wall 54 is provided at a position surrounding the first outer peripheral wall 24 of the first recess 22 of the aluminum plate 20.

  In the present embodiment, in the preparation step, the second bottom surface portion 52a of the second concave portion 52 of the steel plate 50 and the first bottom surface portion 22a of the first concave portion 22 of the aluminum plate 20 are brought into contact with each other. The adhesive 40 is applied so that the adhesive 40 is interposed in the portion. Specifically, the adhesive between the surface 26 of the aluminum plate 20 and the surface 56 of the steel plate 50 and between the first outer peripheral wall 24 of the first recess 22 and the second outer peripheral wall 54 of the second recess 52. 40 is interposed.

  And in the said joining process, the 1st bottom face part 22a of the said 1st recessed part 22 is pressed with the rotary tool 16, and the 2nd recessed part 52 of the 1st bottom face part 22a of this 1st recessed part 22 and the said steel plate 50 is 2nd. Solid phase bonding is performed with the bottom surface portion 52a. At this time, the adhesive 40 around the first recess 22 is sandwiched between the first outer peripheral wall 24 of the first recess 22 and the second outer peripheral wall 54 of the second recess 52 as shown in FIG. As a result, even when the pressing force of the rotary tool 16 is received, it remains around the first recess 22 without being pushed outward.

  Thus, according to this embodiment, by surrounding the first outer peripheral wall 24 of the first recess 22 with the second outer peripheral wall 54 of the second recess 52, the aluminum plate 20 and the steel plate 50 in the periphery Since the adhesive 40 can be more reliably interposed between the two, the bonding strength between the aluminum plate 20 and the steel plate 50 can be more reliably ensured. Furthermore, when the metal materials to be joined are different as described above, it is possible to more reliably avoid water and the like from entering the periphery of the first outer peripheral wall 24 of the first recess 22 and causing electrolytic corrosion. It becomes.

Here, the shape of the aluminum plate, has a limited above.

As shown in FIGS. 13 and 14, the bead portion 64 is preferably Ru with aluminum plate 60 formed as a rigid portion protruding in a direction away from the steel plate 30 from the surface 66. For example, the bead portion 64 may have a shape surrounding the entire periphery of the bonded portion P1. In such a case, the rotating tool 16 is pressed against the joined portion P1 surrounded by the bead portion 64 to apply frictional heat, whereby the bead portion 64 causes the aluminum plate 60 to be pressed as shown in FIG. The steel plate 30 can be solid-phase bonded while suppressing deformation. Further, as shown in FIG. 16, an aluminum plate 70 in which a plurality of bead portions 74 are formed in a state of being separated from each other at a position surrounding the bonded portion P1 may be used.

  Further, the type of the adhesive 40 is not limited to the above, and an adhesive that cures at room temperature may be used. For example, an epoxy resin that cures at room temperature / 24 h and has a viscosity of about 80 Pa · s (27 ° C.) and a tensile shear bond strength of about 29.4 MPa may be used. Thus, when using a room temperature curing adhesive, the step of applying hot air or the like to the adhesive 40 in the bonding step can be omitted. Further, when such an adhesive having a relatively low viscosity is used, there is a high possibility that the adhesive will be pushed outward from the joint portion P by the pressing force of the rotary tool 16, as described above. The friction point joining method according to the present invention, which can suppress the adhesive from being extruded, is particularly effective.

  Moreover, in the said embodiment, although the example which joins an aluminum plate and a steel plate was shown, the friction point joining method of this invention is applicable not only to the combination of the above metal members as long as it is metal members. is there. For example, a magnesium alloy can be used as the metal member (first metal member) on the side into which the rotary tool 16 is pushed.

It is explanatory drawing for demonstrating the conventional friction point joining method. It is sectional drawing which shows the joining state by the conventional friction point joining method. It is a figure which shows typically an example of an apparatus suitable for the friction point joining method concerning this invention. It is a figure which expands and shows the front-end | tip part of the rotation tool of the apparatus shown in FIG. It is sectional drawing which shows the condition which apply | coated the adhesive agent of the surface of a steel plate in the preparatory process of the friction point joining method which concerns on 1st embodiment of this invention. It is sectional drawing which shows the condition which piled up the steel plate and the aluminum plate in the preparatory process of the friction point joining method which concerns on 1st embodiment of this invention. It is sectional drawing for demonstrating the 1st press process in a friction point joining method. It is sectional drawing for demonstrating the 2nd press process in a friction point joining method. It is sectional drawing for demonstrating the 3rd press process in a friction point joining method. It is sectional drawing for demonstrating the condition when joining by the solid-phase body in the friction point joining method is completed. It is sectional drawing for demonstrating the friction point joining method which concerns on 2nd embodiment of this invention. It is sectional drawing for demonstrating the condition when the joining in the solid-phase state by the friction point joining method which concerns on 2nd embodiment of this invention is completed. It is a schematic perspective view for demonstrating the friction point joining method which concerns on other embodiment of this invention. It is sectional drawing for demonstrating the friction point joining method which concerns on other embodiment of this invention shown in FIG. It is sectional drawing for demonstrating the condition when joining in the solid-phase state by the friction point joining method which concerns on other embodiment of this invention shown in FIG. 13 is completed. It is a schematic perspective view for demonstrating the friction point joining method which concerns on other embodiment of this invention.

Explanation of symbols

1 Friction spot welding device 16 Rotating tool 20 Aluminum alloy plate (first metal member)
22 1st recessed part 22a 1st bottom face part 24 1st outer peripheral wall 26 Surface 30 Steel plate (2nd metal member which concerns on 1st embodiment)
40 Adhesive 50 Steel plate (second metal member according to the second embodiment)
52 2nd recessed part 52a 2nd bottom face part 54 2nd outer peripheral wall 56 Surface 60 Other examples (1st metal member) of an aluminum alloy plate
64 Bead part P1 Joined part P Joined part

Claims (4)

It is a method of overlapping the first metal member and the second metal member and joining the two metal members in a solid phase state,
As the first metal member, a metal member provided with a rigid portion for increasing the rigidity in the vicinity of the bonded portion at a position surrounding the bonded portion bonded to the second metal member in a solid phase state,
A preparatory step of superimposing the two metal members in a state in which an insulating adhesive is interposed between the first metal member having the rigid portion and the second metal member;
A rotating tool is brought into contact with a portion to be joined of the first metal member, and the portion to be joined of the first metal member is softened and plastically flowed by frictional heat generated by a rotating operation and a pressing operation of the rotating tool. A joining step of joining the metal members in a solid phase;
A bonding step of bonding a portion other than the bonding portion in the solid state of both metal members with the adhesive,
As the first metal member, a metal member in which a bead portion protruding in a direction away from the second metal member from the surface of the first metal member is formed at a position surrounding the bonded portion,
The rigid part is constituted by the bead part,
In the joining step, the deformation of the first metal member due to the frictional heat is suppressed by the bead portion constituting the rigid portion , and the bonded portion of the first metal member and the second metal member are solid-phased. A friction point joining method characterized by joining in a state .   In the friction point joining method according to claim 1,
  A friction point joining method, wherein an aluminum alloy plate is used as the first metal member, and a steel plate is used as the second metal member.   In the friction point joining method according to claim 1 or 2,
  In the preparation step, the adhesive is interposed between a portion of the first metal member other than the bonded portion and a portion of the second metal member other than the portion bonded to the bonded portion. A friction point joining method characterized by comprising: It is a method of overlapping the first metal member and the second metal member and joining the two metal members in a solid phase state,
  As the first metal member, a metal member provided with a rigid portion for increasing the rigidity in the vicinity of the bonded portion at a position surrounding the bonded portion bonded to the second metal member in a solid phase state,
  A preparatory step of superimposing the two metal members in a state in which an insulating adhesive is interposed between the first metal member having the rigid portion and the second metal member;
  A rotating tool is brought into contact with a portion to be joined of the first metal member, and the portion to be joined of the first metal member is softened and plastically flowed by frictional heat generated by a rotating operation and a pressing operation of the rotating tool. A joining step of joining the metal members in a solid phase;
  A bonding step of bonding a portion other than the bonding portion in the solid state of both metal members with the adhesive,
  In the preparation step, the adhesive is interposed between a portion of the first metal member other than the bonded portion and a portion of the second metal member other than the portion bonded to the bonded portion. Let
  In the joining step, the two metal members are joined while the deformation of the first metal member due to the frictional heat is suppressed by the rigid portion.

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