JP2019171460A - Dissimilar material joining method - Google Patents

Abstract

To provide a dissimilar material joining method by which a peel strength can be improved, and a joined metallic component and a joined resin component can be easily joined.SOLUTION: A dissimilar material joining method comprises: a process in which a joined resin component having a first face, a second face and an open hole is prepared, and a joined metallic component and a metallic component for joining are prepared; a process in which the joined metallic component, the joined resin component and the metallic component for joining are overlapped so that the open hole of the joined resin component is covered with the joined metallic component from the first face side, and is covered with the metallic component for joining from the second face side; and a process in which the metallic component for joining is pushed into the open hole by a rotating joining tool, and is friction stir-joined to the joined metallic component.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a dissimilar material joining method for joining a metal member to be joined and a resin member to be joined.

  Conventionally, various methods are known as methods for joining two members to be joined.

  For example, a method using rivets is known as a method for joining two members to be joined. For example, in Patent Document 1, a rivet joins two laminated plate materials (CFRP) via a washer. The washer is used to receive a collision force when driving a rivet and to suppress delamination of the laminated sheet material. Moreover, as a method of joining two to-be-joined members, the method of using a volt | bolt etc. other than a rivet is also mentioned.

  However, in the method using rivets and bolts, the weight at the joint between the members to be joined can increase. In particular, when at least one of the two members to be joined is formed of a resin material for the purpose of reducing the weight, there is a problem that using rivets or bolts is contrary to the purpose of reducing the weight. .

  Therefore, a method using friction stir welding is known as a method for joining two members to be joined (see, for example, Patent Documents 2 to 5). Since the friction stir welding does not use the rivet or bolt described above, it is possible to prevent the weight of the joint from increasing.

  Friction stir welding is a method of joining two members to be joined using frictional heat. In Patent Documents 2 and 3, the metal member to be bonded and the resin member to be bonded are overlapped, and a rotating bonding tool is pressed against the metal member to be bonded. Then, frictional heat is generated by friction between the welding tool and the metal member to be bonded, and this frictional heat is transmitted to the resin member to be bonded through the interface between the metal member to be bonded and the resin member to be bonded. Is heated above its melting point and melts locally. Thereafter, when the welding tool is separated from the bonded metal member and cooled, the molten portion of the bonded resin member is cured and welded to the interface with the bonded metal member. As a result, the metal member to be bonded is bonded to the resin member to be bonded.

  As another method for joining the metal member to be joined and the resin member to be joined, there is also a method of bonding the metal member to be joined and the resin member to be joined using an adhesive. It is known that many high-strength adhesives generally used for mechanical structures have high shear strength but low peel strength. For this reason, when the metal member to be bonded and the resin member to be bonded are bonded using an adhesive, the metal material of the metal member to be bonded is welded to the resin member to be bonded by the methods shown in Patent Documents 2 and 3. In this case, the shear strength at the bonded portion between the metal member to be bonded and the resin member to be bonded can be secured, but it is difficult to ensure the peel strength.

  Furthermore, a laser rivet bonding method has been proposed as another method for bonding a metal member to be bonded and a resin member to be bonded (for example, see Non-Patent Document 1). This is by sandwiching a bonded resin member in which a through hole is formed between the bonded metal member and the metal washer, and welding the bonded metal member and the metal washer with a laser beam through the through hole. In this method, the metal member to be bonded and the resin member to be bonded are bonded. In order to weld the metal member to be joined and the metal washer with laser light, it is preferable that the gap between the metal member to be joined and the metal washer is not provided or that the gap is small. For this reason, the to-be-joined metal member and the metal washer are each formed in a shape that enters the through hole.

Japanese Patent No. 5838537 Japanese Patent Laying-Open No. 2015-131443 Japanese Patent No. 5817140 Japanese Patent No. 3429475 Japanese Patent No. 5854451

Development of High Power Direct Diode Laser Equipped Remote Laser Welding Robot System “LAPRISS” and Welding Process, Kawamoto Welding Society Journal Vol.85 (2016) No.8 PP.7-9

  However, in the method shown in Non-Patent Document 1, high accuracy is required for processing the metal member to be bonded and the metal washer to the above-described shape. On the other hand, if a certain amount of gap is formed between the metal member to be bonded and the metal washer, welding between the metal member to be bonded and the metal washer becomes insufficient, and sufficient strength may not be obtained. For this reason, it is considered that cost and labor are spent on managing the gap, and it becomes difficult to join the metal member to be joined and the resin member to be joined.

  The present invention has been made in view of such points, and provides a dissimilar material joining method that can improve peel strength and can easily join a metal member to be joined and a resin member to be joined. The purpose is to do.

The present invention
A dissimilar material joining method for joining a joined metal member and a joined resin member using a joining metal member,
While preparing the said to-be-joined resin member which has a 1st surface, the 2nd surface provided in the opposite side to the said 1st surface, and the through-hole formed ranging from the said 1st surface to the said 2nd surface. Preparing the bonded metal member and the bonding metal member;
The to-be-joined metal member so that the through-hole of the to-be-joined resin member is covered with the to-be-joined metal member from the first surface side and is covered with the to-be-joined metal member from the second surface side. A step of superimposing the bonded resin member and the bonding metal member;
A step of pushing the metal member for joining into the through-hole with a rotating joining tool and friction stir joining the metal member to be joined.
I will provide a.

In the dissimilar material joining method described above,
The bonding metal member has a flat first surface provided on the bonded resin member side, and a flat second surface provided on the side opposite to the first surface. Yes,
You may do it.

In the dissimilar material joining method described above,
The bonded metal member has a flat first surface provided on the side opposite to the bonded resin member, and a flat second surface provided on the bonded resin member side. ing,
You may do it.

In the dissimilar material joining method described above,
The bonded metal member is formed of steel, copper, copper alloy, aluminum alloy, magnesium alloy or titanium alloy,
You may do it.

In the dissimilar material joining method described above,
The bonded resin member is formed of a fiber reinforced plastic material,
You may do it.

In the dissimilar material joining method described above,
The bonded resin member is formed of a thermosetting resin.
You may do it.

In the dissimilar material joining method described above,
The bonded resin member is formed of a thermoplastic resin.
You may do it.

In the dissimilar material joining method described above,
In the step of superimposing the metal member to be bonded, the resin member to be bonded, and the metal member for bonding, between the metal member to be bonded and the resin member to be bonded, and the resin member to be bonded and the metal member for bonding. Insulating members are interposed in at least one of
You may do it.

In the dissimilar material joining method described above,
The insulating member is an adhesive, a sealing material, or a resin sheet.
You may do it.

In the dissimilar material joining method described above,
The planar shape of the through hole of the bonded resin member is a circle.
You may do it.

In the dissimilar material joining method described above,
The bonded metal member has a first surface provided on the opposite side to the bonded resin member, and a second surface provided on the bonded resin member side,
The joining tool has a tool body and a spherical probe protruding from the tip of the tool body,
The tool radius of the probe is r, the thickness of the metal member to be bonded is t ₁ , the thickness of the resin member to be bonded is t ₂ , the thickness of the metal member for bonding is t ₃ , and The probe pressing depth is D, the distance between the tip of the probe pressed into the pressing position where the probe is pressed at the pressing depth D and the first surface of the bonded metal member is d, the tool When the diameter of the main body is φ _S and the radius of the through hole is R, the diameter φ _{M of the} through hole is
Meets
You may do it.

In the dissimilar material joining method described above,
The bonded metal member has a first surface provided on the opposite side to the bonded resin member, and a second surface provided on the bonded resin member side,
The joining tool has a tool body and a truncated cone-shaped probe protruding from the tip of the tool body,
The probe includes a flat tip surface, and an inclined surface whose diameter decreases from the tool body toward the tip surface,
The tool radius of the probe is r ₁ , the thickness of the metal member to be bonded is t ₁ , the thickness of the resin member to be bonded is t ₂ , the thickness of the metal member for bonding is t ₃ , and at the time of friction stir welding The probe pressing depth is D, the distance between the tip of the probe and the first surface of the metal member to be joined at the pressing position where the probe is pressed at the pressing depth D is d, The radius of the tip surface is r ₂ , the radius of the second surface of the bonded resin member of the probe pushed into the pushing position is r ₃ , and the probe pushed into the pushing position and the wall surface of the through-hole distance r ₄ in the second surface of the object to be bonded resin _members, the protruding dimension of the probe L, when the radius of the through hole was R, the diameter of the tool body and phi _S, the diameter of the through hole φ _M is
May be satisfied.

In the dissimilar material joining method described above,
The planar shape of the through hole of the bonded resin member has a longitudinal direction.
You may do it.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to improve peeling strength, a to-be-joined metal member and a to-be-joined resin member can be joined easily.

FIG. 1 is a cross-sectional view showing a bonded structure obtained by the dissimilar material bonding method according to the present embodiment. FIG. 2 is a plan view of the joint structure of FIG. FIG. 3 is a schematic view showing an example of a joining apparatus for carrying out the dissimilar material joining method according to the embodiment of the present invention. 4 is an enlarged view showing a joining tool of the joining apparatus of FIG. FIG. 5A is a diagram illustrating a process of preparing a metal plate, a resin plate, and a metal washer in the dissimilar material joining method according to the present embodiment, and FIG. 5B is a diagram illustrating a metal plate, a resin plate, and a metal washer. 5 (c) is a diagram showing a state before the joining tool is pressed against the metal washer, and FIG. 5 (d) is a diagram showing a state in which the joining tool is pushed in. FIG. 5 (e) is a view showing a state where the joining tool is raised. FIG. 6 is a diagram showing a modification of the process shown in FIG. FIG. 7 is a cross-sectional view showing a modification of the bonded structure of FIG. FIG. 8 is a plan view of the joint structure of FIG. FIG. 9 is a view showing a modification of the joining tool of FIG. FIG. 10A is a photograph showing a cross section of the joining structure as Example 1, and FIG. 10B is a photograph showing an enlarged part of the cross section of FIG. FIG. 11 is a photograph showing an enlarged part of a cross section of the bonded structure as Comparative Example 1-1. FIG. 12A is a plan view showing a test piece used in the tensile shear strength test, and FIG. 12B is a diagram for explaining a tensile shear strength test method using the test piece of FIG. FIG. FIG. 13 is a graph showing the tensile shear strength in Example 1 and the tensile shear strength in Comparative Example 1-2. FIG. 14A is a plan view showing a test piece used in the test method for cross tensile strength, and FIG. 14B illustrates a cross tensile strength test method using the test piece shown in FIG. It is a schematic diagram for doing. FIG. 15 is a graph showing the tensile shear strength and the cross tensile strength in Example 1 and Comparative Example 1-3. FIG. 16 is a graph showing the tensile shear strength per unit bonding area and the cross tensile strength per unit bonding area in Example 1 and Comparative Example 1-3. FIG. 17 is an enlarged photograph showing a part of the cross section of the bonded structure as Example 2-2. FIG. 18 is a graph showing the tensile shear strength in Example 2. FIG. 19 is a graph showing the tensile shear strength in Example 3. FIG. 20 is a graph showing the tensile shear strength in Example 4. FIG. 21 is a graph showing the tensile shear strength in Example 5. FIG. 22 is a graph showing the tensile shear strength in Example 6. FIG. 23 is a table summarizing the tensile shear strength test results obtained in Examples 3 to 6. FIG. 24 is a graph plotting the test results shown in FIG. FIG. 25 is a diagram showing a geometric model for obtaining a predicted value of the through hole shown in FIGS. 23 and 24. FIG. 26 is a diagram showing a geometric model for the joining tool shown in FIG. 9.

  Embodiments of the present invention will be described below with reference to the drawings.

  With reference to FIGS. 1-8, the dissimilar material joining method in embodiment of this invention is demonstrated. The dissimilar material joining method in the present embodiment is a method for joining a metal member to be joined and a resin member to be joined using a metal member for joining. First, a bonded structure 10 obtained by the dissimilar material bonding method according to the present embodiment will be described with reference to FIG. The bonded structure 10 according to the present embodiment is a structure in which a metal plate 11 (bonded metal member) and a resin plate 12 (bonded resin member) are bonded, and more specifically, the metal plate 11 and It is a structure obtained by friction stir welding a metal washer 13 (metal member for joining) with a resin plate 12 sandwiched therebetween. Friction stir welding refers to joining a plurality of members by softening, stirring, and curing the members by frictional heat generated by the rotational force of the welding tool.

  As shown in FIGS. 1 and 2, the joining structure 10 includes a metal plate 11, a resin plate 12 directly superimposed on the metal plate 11, and a metal washer directly superimposed on the resin plate 12. 13. Among these, the metal plate 11 includes a first surface 11a provided on the opposite side to the resin plate 12, and a second surface 11b provided on the opposite side (resin plate 12 side) to the first surface 11a. Have. Both the first surface 11a and the second surface 11b are formed in a flat shape, and the metal plate 11 is formed in a flat plate shape. The resin plate 12 has a first surface 12a provided on the metal plate 11 side, a second surface 12b provided on the opposite side of the first surface 12a, and a through hole 14. The first surface 12a and the second surface 12b are both formed in a flat shape, and the resin plate 12 is formed in a flat plate shape. The metal washer 13 has a first surface 13a provided on the resin plate 12 side and a second surface 13b provided on the side opposite to the first surface 13a. Both the first surface 13a and the second surface 13b are formed in a flat shape, and the metal washer 13 is formed in a flat plate shape. The first surface 12 a of the resin plate 12 is overlaid on the second surface 11 b of the metal plate 11, and the first surface 13 a of the metal washer 13 is overlaid on the second surface 12 b of the resin plate 12. Thus, the metal plate 11, the resin plate 12, and the metal washer 13 are laminated in this order.

  As shown in FIG. 1, the through hole 14 is formed from the first surface 12 a to the second surface 12 b of the resin plate 12, and penetrates the resin plate 12. In addition, as shown in FIG. 2, the through hole 14 has a shape smaller than the region where the metal plate 11 and the resin plate 12 overlap, and has a shape smaller than the region where the metal washer 13 and the resin plate 12 overlap. is doing. That is, the entire through hole 14 is covered with the metal plate 11 from the first surface 12 a side of the resin plate 12. Further, the entire through hole 14 is covered with a metal washer 13 from the second surface 12 b side of the resin plate 12. In other words, the metal washer 13 has a planar shape that can cover the entire through hole 14 of the resin plate 12. The planar shape of the through hole 14 is arbitrary, but may be circular as shown in FIG. In this case, the metal plate 11 and the metal washer 13 are friction stir spot joined.

  A part of the metal washer 13 enters the through hole 14 of the resin plate 12 to form a part of the friction stir welding part 15. The friction stir joint 15 is constituted by a softened portion of the metal washer 13 pushed into the through hole 14 and a softened portion of the metal plate 11. The friction stir welding part 15 joins and integrates the metal plate 11 and the metal washer 13. The metal washer 13 is pressed against the second surface 12b of the resin plate 12 by a joining tool 42 described later. In this way, the resin plate 12 is joined to the metal plate 11. That is, by the friction force acting between the metal plate 11 and the resin plate 12 and the friction force acting between the resin plate 12 and the metal washer 13, the stacking direction and the direction orthogonal to the stacking direction (the horizontal direction in FIG. 2). And the vertical direction), the metal plate 11 and the resin plate 12 are immovable relative to each other and are fixed to each other. Here, the description that the metal plate 11 and the resin plate 12 are joined relates to whether or not the metal material forming the metal plate 11 and the resin material forming the resin plate 12 are directly joined to each other. Instead, even when a force smaller than the strength of the bonded structure 10 is applied by bonding the metal washer 13 to the metal plate 11, the metal plate 11 and the resin plate 12 can be arbitrarily three-dimensionally. It is treated as meaning that it is fixed so that relative movement is impossible in the direction of. In FIG. 1, an example in which the friction stir joint 15 is fitted in the through hole 14 of the resin plate 12 is shown, but the present invention is not limited to this.

  As shown in FIG. 1, a continuous concave surface 16 is formed in the friction stir welding portion 15. The concave surface 16 is formed in a curved shape so as to be convex downward. That is, the concave surface 16 is a surface formed by being pressed by a probe 44 described later, and is formed along the curved surface 44 a of the probe 44. When the probe 44 enters the metal plate 11 during friction stir welding, a part of the concave surface 16 is formed so as to enter the metal plate 11 side with respect to the first surface 12 a of the resin plate 12.

  The material used for the metal plate 11 is not particularly limited as long as it can be suitably friction stir welded to the metal washer 13. For example, the metal plate 11 may be formed of steel, copper, a copper alloy, an aluminum alloy, a magnesium alloy, or a titanium alloy. The plate thickness (thickness before joining) of the metal plate 11 is, for example, 0.1 mm to 50 mm, preferably 0.5 mm to 5 mm.

  The material used for the resin plate 12 is not particularly limited, but the resin plate 12 may be formed of, for example, a fiber reinforced plastic material. The fiber reinforced plastic material may be carbon fiber reinforced plastic (CFRP). Further, the fiber reinforced plastic material may be impregnated with a thermosetting resin or may be impregnated with a thermoplastic resin. Further, the resin plate 12 may be formed of a thermosetting resin or a thermoplastic resin without including fibers. The plate thickness (thickness before joining) of the resin plate 12 is, for example, 0.1 mm to 10 mm, preferably 0.5 mm to 5 mm.

  The material used for the metal washer 13 is not particularly limited as long as it can be suitably friction stir welded to the metal plate 11. For example, the metal washer 13 may be formed of steel, copper, a copper alloy, an aluminum alloy, a magnesium alloy, or a titanium alloy. The plate thickness (thickness before joining) of the metal washer 13 is, for example, 0.1 mm to 10 mm, preferably 0.5 mm to 3 mm.

  Next, an example of the bonding apparatus 30 for forming such a bonded structure 10 will be described with reference to FIG.

  As shown in FIG. 3, the joining device 30 includes a base 31 and a housing 32 fixed on the base 31. A servo motor 33 is provided in the housing 32. A ball screw 34 extends upward from the servo motor 33. A ball nut 35 is screwed to the ball screw 34, and a slider 36 is fixed to the ball nut 35. The housing 32 is provided with a guide rail 37 extending in the vertical direction, and the slider 36 is guided by the guide rail 37 and is movable in the vertical direction.

  An induction motor 38 is fixed to the slider 36. An output shaft 39 extends downward from the induction motor 38. The output shaft 39 is rotatably supported by a bearing member 40 fixed to the slider 36. A tool holding portion 41 is provided below the bearing member 40. The tool holding portion 41 is fixed to the output shaft 39 and holds the joining tool 42.

  With such a configuration, when the servo motor 33 is driven, the ball screw 34 rotates and the slider 36 moves up or down. As the slider 36 is raised or lowered, the joining tool 42 held by the tool holding portion 41 is raised or lowered. Then, when the induction motor 38 is driven, the welding tool 42 is rotated.

As shown in FIG. 4, the joining tool 42 held by the tool holding portion 41 includes a cylindrical tool body 43 formed along an axis extending in the vertical direction, a probe 44 attached to the tool body 43, have. The tool main body 43 includes a flat shoulder surface 43a. The shoulder surface 43a constitutes the front end surface (lower end surface) of the tool main body 43 and has a shoulder diameter φ _S. Probe 44 has a tool diameter phi _T shown in FIG. 4, and protrudes from the shoulder surface 43a downward (see protrusion dimension shown in FIG. 25 L). The probe 44 is formed in a spherical shape and includes a spherical curved surface 44a. That is, the tool diameter phi _T of the probe 44 according to this embodiment, and corresponds to the diameter of the formed sphere by a curved surface 44a. The curved surface 44 a is pressed against the metal washer 13. Since the joining tool 42 shown in FIG. 4 has a probe 44 including a spherical curved surface 44a, it is also called a spherical tool.

  The material used for the probe 44 is not particularly limited as long as it can withstand the temperature rise during friction stir welding. For example, the probe 44 may be formed of ceramics (for example, silicon nitride), cemented carbide (for example, tungsten alloy), heat-resistant alloy (for example, cobalt alloy, nickel alloy), or cubic boron nitride (PCBN). . The tool main body 43 may be formed of the same material as that of the probe 44, and may be formed of a steel material as long as it can withstand the temperature rise.

  A work holding part 45 that holds the metal plate 11, the resin plate 12, and the metal washer 13 is provided below the joining tool 42. The work holding part 45 is fixed to the base 31 described above. The housing 32 is provided with a control panel 46 for controlling the servo motor 33 and the induction motor 38 described above.

  Next, a dissimilar material joining method according to the present embodiment, that is, a method of joining the metal plate 11 and the resin plate 12 will be described with reference to FIG.

  First, as a first step, as shown in FIG. 5A, a metal plate 11, a resin plate 12, and a metal washer 13 are prepared. Among these, the resin plate 12 is previously formed by machining or the like with the above-described through hole 14 as a pilot hole. The metal washer 13 has a planar shape that can cover the through hole 14 of the resin plate 12, and is preferably formed in a flat plate shape.

  Subsequently, as a second step, as shown in FIG. 5B, the metal plate 11, the resin plate 12, and the metal washer 13 are overlapped. In this case, first, the metal plate 11 is placed on the work holding part 45 (see FIG. 3) of the joining device 30. Subsequently, the resin plate 12 is overlaid on the metal plate 11 so that the through hole 14 is covered with the metal plate 11 from the first surface 12a side. Next, the metal washer 13 is overlaid on the resin plate 12 so that the through hole 14 is covered from the second surface 12b side. Then, the metal plate 11, the resin plate 12, and the metal washer 13 that are overlaid on each other are fixed to the work holding unit 45 by a fixing unit (not shown).

  Next, as a third step, the metal washer 13 is pushed into the through hole 14 with the rotating joining tool 42 of the joining device 30 and friction stir joined to the metal plate 11.

  In this case, first, as shown in FIG. 5 (c), the induction motor 38 (see FIG. 3) is rotationally driven by a command from the control panel 46. As a result, the joining tool 42 held by the tool holding portion 41 together with the output shaft 39 rotates at a desired number of rotations.

  Subsequently, the servo motor 33 is driven to rotate by a command from the control panel 46. As a result, the ball screw 34 rotates and the joining tool 42 moves down together with the slider 36. During this time, the induction motor 38 continues to be driven to rotate, and the welding tool 42 continues to rotate.

  When the joining tool 42 is lowered, the tip of the probe 44 reaches the second surface 13b of the metal washer 13, and the rotating probe 44 is pressed against it. As a result, frictional heat is generated by friction between the metal washer 13 and the probe 44. Due to the generated frictional heat, a portion of the metal washer 13 near the probe 44 (a portion overlapping the through hole 14) is softened.

  The joining tool 42 continues to descend while rotating. As a result, the softened portion of the metal washer 13 is pushed into the through hole 14 of the resin plate 12 as the joining tool 42 is lowered, as shown in FIG. The softened portion pushed into the through hole 14 is expanded and pushed down toward the metal plate 11 in the through hole 14. The softened portion of the metal washer 13 comes into contact with the metal plate 11 by being pushed down. When the softened portion comes into contact with the metal plate 11, the generated frictional heat is transmitted from the metal washer 13 to the metal plate 11, and the portion of the metal plate 11 near the probe 44 is also softened.

  The probe 44 has a desired pushing depth (depth from the second surface 13b of the metal washer 13, for example, depth until the tip of the probe 44 reaches below the second surface 11b of the metal plate 11). It is pushed to the pushing position. At this pushing position, the rotation of the servo motor 33 is stopped by a command from the control panel 46, whereby the welding tool 42 is stopped at the pushing position. This stop state is maintained for a predetermined time (hereinafter referred to as indentation holding time). During this time, the softened portion of the metal washer 13 is pushed away from the tip of the probe 44 by the centrifugal force of the rotation of the probe 44, and moves to the periphery along the curved surface 44a of the probe 44. A part of the softened portion of the metal plate 11 is pushed away from the tip of the probe 44 and moves to the periphery along the curved surface 44 a of the probe 44. In this way, the concave surface 16 (see FIG. 1) of the friction stir welding portion 15 is formed along the curved surface 44a of the probe 44. In addition, since the probe 44 does not descend from the pushing position, the portion of the metal plate 11 opposite to the resin plate 12 (the lower portion) remains.

  Note that the probe 44 does not move in the direction along the first surface 12a (or the second surface 12b) of the resin plate 12 (the left-right direction and the up-down direction in FIG. 2) after reaching the pushing position. For this reason, the friction stir welding obtained by the present embodiment is more accurately the friction stir spot welding.

  Further, the shoulder surface 43a of the tool main body 43 may be in contact with the second surface 13b of the metal washer 13 (particularly, the softened portion of the metal washer 13) while the probe 44 is positioned at the pushing position. Accordingly, it is possible to prevent the shoulder surface 43a from pressing the metal washer 13 downward and the softened portion of the metal washer 13 from rising upward. Further, the metal washer 13 can be pressed against the second surface 12b of the resin plate 12 so as to suppress the swelling of the softened portion of the metal washer 13 in this way, and the frictional force between the metal plate 11 and the resin plate 12 can be reduced. In addition, the resin plate 12 can be firmly held between the metal plate 11 and the metal washer 13 by applying a frictional force between the resin plate 12 and the metal washer 13. In FIG. 5D, in order to simplify the drawing, the shoulder surface 43a and the second surface 13b of the metal washer 13 are shown separated from each other. However, as described above, the shoulder surface 43a You may make it contact | abut to the 2nd surface 13b of the metal washer 13, or the softened part of the metal washer 13.

  After the push-in holding time has elapsed at the push-in position, as shown in FIG. 5E, the joining tool 42 is raised by rotating the servo motor 33 in the reverse direction in response to a command from the control panel 46. As a result, the probe 44 is separated from the metal plate 11 and the metal washer 13. Thereafter, the softened portion of the metal washer 13 and the softened portion of the metal plate 11 are cooled and hardened to form a friction stir joint 15 (see FIG. 1) that joins the metal plate 11 and the metal washer 13 together.

  In this way, the metal plate 11 and the metal washer 13 are friction stir welded. The metal washer 13 is pressed against the second surface 12 b (upper surface) of the resin plate 12 and joined to the metal plate 11. As a result, the metal plate 11 and the resin plate 12 cannot be moved relative to each other in a three-dimensional manner and are fixed to each other. In this way, the metal plate 11 and the resin plate 12 are joined, and the joined structure 10 shown in FIG. 1 is obtained.

  Thus, according to the present embodiment, the metal plate 11 is overlaid on the resin plate 12 so that the through hole 14 of the resin plate 12 is covered from the first surface 12a side, and the through hole 14 is on the second surface. The metal washer 13 is superimposed on the resin plate 12 so as to be covered from the side of 12b, and the metal washer 13 is pushed into the through hole 14 by the rotating joining tool 42. Thus, the metal tool 11 of the bonding apparatus 30 softens and pushes the metal washer 13 by frictional heat, and the metal plate 11 and the metal washer 13 can be friction-stir welded so as to sandwich the resin plate 12. In this case, since the metal plate 11 and the metal washer 13 which are friction stir welded with metal materials sandwich the resin plate 12, the peel strength between the metal plate 11 and the resin plate 12 can be improved.

  Further, according to the present embodiment, the metal washer 13 and the metal plate 11 are friction-stir joined and the resin plate 12 is sandwiched between the metal plate 11 and the metal washer 13. This can reduce the mass of a member added to join the metal plate 11 and the resin plate 12 (in this embodiment, the metal washer 13) as compared to fastening with rivets or bolts. For this reason, it can suppress that the mass of the junction part of the metal plate 11 and the resin plate 12 increases, and it can suppress that it opposes the objective of achieving weight reduction using the resin plate 12. FIG.

  Further, according to the present embodiment, when the metal plate 11 is overlapped with the resin plate 12, the through hole 14 of the resin plate 12 is covered from the first surface 12 a side, and the metal washer 13 is overlapped with the resin plate 12. When matching, the through hole 14 of the resin plate 12 is covered from the second surface 12b side. The metal washer 13 and the metal plate 11 can be pushed into the through hole 14 by softening the metal washer 13 by the joining tool 42. This eliminates the need to previously form the metal plate 11 and the metal washer 13 into a shape that enters the through hole 14. That is, according to the present embodiment, the metal washer 13 is formed in a flat plate shape and the metal plate 11 is formed in a flat plate shape. Even in this case, the metal washer 13 and the metal plate 11 can be friction stir welded in the through hole 14. For this reason, the preparation process of the metal plate 11 and the metal washer 13 can be simplified, and the metal plate 11 and the resin plate 12 can be easily joined.

  Moreover, according to this Embodiment, since the through-hole 14 is provided in the resin plate 12, it can prevent that the resin material which forms the resin plate 12 is stirred with the softened part of the metal washer 13. FIG. This can prevent the resin plate 12 from being deformed or altered. In particular, when the resin plate 12 is formed of a fiber-reinforced plastic material, the reinforcing fiber can be prevented from being deformed or broken by the rotation of the probe 44. For this reason, the strength of the fiber reinforced plastic material can be maintained, and the strength of the resin plate 12 can be prevented from decreasing.

  Further, according to the present embodiment, the resin plate 12 is provided with the through hole 14 and the metal plate 11 is friction stir joined to the metal washer 13 so that the resin material forming the resin plate 12 does not need to be stirred. Can be. For this reason, even if the resin plate 12 is a thermosetting resin, the metal plate 11 and the resin plate 12 can be joined easily.

  Further, according to the present embodiment, when the resin plate 12 is formed of a thermoplastic resin, the thermoplastic resin is caused by the heat generated when the metal plate 11 and the metal washer 13 are friction stir joined. Melt. Thus, after cooling, the metal plate 11 can be welded to the first surface 12 a of the resin plate 12, and the metal washer 13 can be welded to the second surface 12 b of the resin plate 12. For this reason, the tensile shear strength between the metal plate 11 and the resin plate 12 can be improved.

  Moreover, according to this Embodiment, the planar shape of the through-hole 14 of the resin board 12 is circular. As a result, the metal plate 11 and the metal washer 13 are friction stir spot joined by the probe 44 of the joining device 30. That is, in a state where the probe 44 is pushed to a predetermined pushing position, it is unnecessary to move the joining tool 42 including the probe 44 in the direction along the first surface 12a or the second surface 12b of the resin plate 12. For this reason, work efficiency can be improved and the metal plate 11 and the resin plate 12 can be joined easily. Moreover, the structure of the joining apparatus 30 can be simplified.

  As mentioned above, although embodiment of this invention has been described in detail, the dissimilar material joining method by this invention is not limited to the said embodiment at all, In the range which does not deviate from the meaning of this invention, various changes are possible. Is possible.

  For example, in the present embodiment described above, an example in which the resin plate 12 is directly superimposed on the metal plate 11 and the metal washer 13 is directly superimposed on the resin plate 12 has been described. However, the present invention is not limited to this. For example, as shown in FIG. 6, when the metal plate 11, the resin plate 12, and the metal washer 13 are overlapped, at least one between the metal plate 11 and the resin plate 12 and between the resin plate 12 and the metal washer 13. Further, the insulating member 50 may be interposed. In the example shown in FIG. 6, insulating members 50 are respectively interposed between the metal plate 11 and the resin plate 12 and between the resin plate 12 and the metal washer 13. In this case, the metal plate 11 and the resin plate 12 can be electrically insulated, and the resin plate 12 and the metal washer 13 can be electrically insulated. For example, when the resin plate 12 is formed of a carbon fiber reinforced plastic material, electrolytic corrosion can be prevented.

  The insulating member 50 may be an adhesive, a sealing material, or a resin sheet. Of these, any material may be used for the adhesive as long as it has a function of bonding the metal plate 11 and the resin plate 12 and bonding the resin plate 12 and the metal washer 13 while having insulating properties. For example, an adhesive for weld bonding can be used. When an adhesive is used for the insulating member 50, the joint strength including the peel strength between the metal plate 11 and the resin plate 12 is increased by a synergistic effect of the joint force by friction stir welding and the joint force by the adhesive. Can do. Any material may be used for the sealing material as long as it has a function of bringing the metal plate 11 and the resin plate 12 into close contact with each other and having the function of bringing the resin plate 12 and the metal washer 13 into close contact with each other. For example, a spot sealer used at the time of spot welding can be used. In the case where a sealing material is used for the insulating member 50, electrolytic corrosion of the metal plate 11 and the resin plate 12 can be prevented by a synergistic effect of the joining force by friction stir welding and the waterproof effect by the sealing material. As the resin sheet, any material can be used as long as it has insulating properties. For example, a fluororesin film can be used.

  When a liquid adhesive is used for the insulating member 50, the adhesive is applied to the second surface 11b of the metal plate 11 or the second surface 12b of the resin plate 12, and the first surface 12a of the resin plate 12 or the metal The insulating member 50 may be formed by applying an adhesive to the first surface 13 a of the washer 13. The same applies to the case where a liquid sealing material is used for the insulating member 50.

  Moreover, in this Embodiment mentioned above, the through-hole 14 of the resin board 12 demonstrated the example which has circular planar shape. However, the present invention is not limited to this, and the through hole 14 may have a longitudinal direction dL as shown in FIGS. 7 and 8. 7 and 8, the through-hole 14 has a longitudinal direction dL extending in the left-right direction on the paper surface. The through hole 14 may be formed as a long hole (such as an ellipse or an ellipse) along the longitudinal direction dL. By providing the bonding device 30 with a function of moving the probe 44 in the plane direction, the probe 44 can be moved in the longitudinal direction dL of the through hole 14 when the probe 44 is pushed into the metal plate 11. For this reason, the area | region of friction stir welding can be increased, and the joining strength of the metal plate 11 and the resin plate 12 can be improved further.

Moreover, in this Embodiment mentioned above, the probe 44 of the joining tool 42 demonstrated the example formed in spherical shape. However, the present invention is not limited to this, and as shown in FIG. 9, the probe 44 of the joining tool 42 may be formed in a truncated cone shape. In this case, the probe 44 has a tool diameter φ _T (tool base diameter, diameter at the shoulder surface 43a) shown in FIG. 9, and protrudes downward from the shoulder surface 43a (see the protrusion dimension L shown in FIG. 26). ing. The probe 44 includes a flat distal end surface 44b and an inclined surface 44c that gradually decreases in diameter from the shoulder surface 43a of the tool main body 43 toward the distal end surface 44b. Since the joining tool 42 shown in FIG. 9 has a truncated cone-shaped probe 44, it is also referred to as a conical tool.

  Moreover, in this Embodiment mentioned above, the example in which the metal washer 13 was formed in flat form was demonstrated. However, the present invention is not limited to this, and the metal washer 13 may be formed such that a convex portion is provided on the flat first surface 13 a and the convex portion enters the through hole 14. Alternatively, the metal washer 13 may be bent so that a part of the first surface 13 a enters the through hole 14. In the latter case, the portion of the first surface 13 a that enters the through hole 14 may be formed in a curved shape, or the first surface 13 a has a step so that the flat portion is positioned in the through hole 14. It may be formed as follows.

  Furthermore, in this Embodiment mentioned above, the example in which the metal plate 11 was formed in flat form was demonstrated. However, the present invention is not limited to this, and the metal plate 11 may be formed such that a convex portion is provided on the flat second surface 11b and the convex portion enters the through hole 14, Alternatively, the metal plate 11 may be bent so that a part of the second surface 11 b enters the through hole 14. In the latter case, the portion of the second surface 11b that enters the through hole 14 may be formed in a curved shape, or the second surface 11b has a step so that the flat portion is positioned in the through hole 14. It may be formed as follows.

  According to the present invention described above, it is possible to provide a dissimilar material joining method capable of improving the peel strength and easily joining the metal member to be joined and the resin member to be joined. For this reason, the present invention is an industrially applicable invention. For example, the present invention can be widely used for joining a metal member to be joined and a resin member to be joined in industrial products such as various machines, structures, and the like.

  The strength test of the joined structure 10 including the metal plate 11 and the resin plate 12 obtained by the dissimilar material joining method according to the present embodiment described above was performed under various conditions. In each example and each comparative example, the material of the metal plate 11 is a cold rolled steel plate, the material of the resin plate 12 is a carbon fiber reinforced plastic impregnated with a thermosetting resin (polyamide 6), and the material of the metal washer 13 is cold. A rolled steel sheet was used. As the joining tool 42, the spherical tool shown in FIG. 4 was used.

Example 1
In Example 1, the bonded structure 10 was obtained under the following conditions.
-Thickness of the metal plate 11: 1 mm
・ Thickness of resin plate 12: 1 mm
-Metal washer 13 thickness: 1 mm
Tool diameter of probe 44 φ _T : 9.53 mm (3/8 inch)
-Diameter φ _M of through-hole 14: 10 mm
Indentation depth (depth from the second surface 13b of the metal washer 13): 2.6 mm

  A cross-sectional photograph of the bonded structure 10 obtained in Example 1 is shown in FIG. 10A is a cross-sectional photograph showing the bonded structure 10, and FIG. 10B is an enlarged cross-sectional photograph showing the friction stir weld 15 in FIG. 10A.

  As shown in FIGS. 10A and 10B, in the friction stir joint 15 constituted by the softened portion of the metal washer 13 and the softened portion of the metal plate 11, the softened portion of the metal washer 13 and the metal plate 11 It can be considered that the resin material of the resin plate 12 as shown in FIG. 11 described later is not interposed between the softened portion. This confirmed that the softened portion of the metal washer 13 and the softened portion of the metal plate 11 were directly and well joined. For this reason, it can be said that the joint strength including the peel strength between the metal plate 11 and the resin plate 12 can be improved.

  10A and 10B, the cross section of the resin plate 12 shows reinforcing fibers extending in the left-right direction. However, the orientation of the reinforcing fibers is disturbed in the vicinity of the through holes 14. It can be said that the reinforcing fibers are not broken by at least friction stir welding. Thus, it was confirmed that the strength of the fiber reinforced plastic material was maintained and the strength reduction of the resin plate 12 could be prevented.

Here, Comparative Example 1-1 will be described. In Comparative Example 1-1, a bonded structure was obtained under the following conditions.
-Thickness of the metal plate 11: 1 mm
・ Thickness of resin plate 12: 1 mm
-Metal washer 13 thickness: 1 mm
Tool diameter of probe 44: 12.70 mm (1/2 inch)
-Diameter of the through hole 14:-(the through hole 14 is not formed)
Indentation depth (depth from the second surface 13b of the metal washer 13): 2.6 mm

  An enlarged cross-sectional photograph of the joined structure obtained in Comparative Example 1-1 is shown in FIG.

  As shown in FIG. 11, in the friction stir welding portion 15 constituted by the softened portion of the metal washer 13 and the softened portion of the metal plate 11, between the softened portion of the metal washer 13 and the softened portion of the metal plate 11, Interposition of the resin material of the resin plate 12 was observed. This confirmed that direct bonding between the softened portion of the metal washer 13 and the softened portion of the metal plate 11 was hindered. Since the through hole 14 is not provided in the resin plate 12, it is considered that the softened portion of the resin material remained between the softened portion of the metal washer 13 and the softened portion of the metal plate 11 during the friction stir welding.

  Further, as shown in FIG. 11, the orientation of the reinforcing fibers was disturbed in the vicinity of the through hole 14, and the reinforcing fibers were confirmed to be broken. Accordingly, since the through hole 14 is not provided in the resin plate 12, it is considered that the reinforcing fiber is broken under the influence of the probe 44 that rotates during the friction stir welding.

  In order to obtain the tensile strength of the bonded structure 10 according to Example 1, a tensile shear strength test was performed. That is, a test piece (joined structure 10) having a planar shape as shown in FIG. 12A was produced under the same conditions as in Example 1. Further, a test piece having the same planar shape was produced under the same conditions as in Comparative Example 1-1 except that the tool diameter of the probe 44 was 9.53 mm (3/8 inch) (Comparative Example 1-2). ). And the tensile shear strength test of both was done. In the tensile shear strength test, as shown in FIG. 12B, the metal plate 11 is pulled in one of the left and right directions (right side in FIG. 12B), and the resin plate 12 is pulled in the other in the left and right direction (FIG. 12B). ) Was pulled to the left side) and the breaking load value was measured. The result is shown in FIG.

  As shown in FIG. 13, it was confirmed that Example 1 (with through-hole 14) has a higher tensile shear strength than Comparative Example 1-2 (without through-hole 14). As shown in the cross-sectional photographs of FIG. 10 and FIG. 11 described above, in Example 1, since no resin material was interposed between the softened portion of the metal washer 13 and the softened portion of the metal plate 11, The softened part of the metal washer 13 and the softened part of the metal plate 11 are directly and well joined. On the other hand, in Comparative Example 1-2, it is considered that the resin material of the resin plate 12 is interposed between a softened portion of the metal washer 13 and a softened portion of the metal plate 11. The joint between the portion and the softened portion of the metal plate 11 is insufficient. For this reason, it can be said that the tensile shear strength of the joining structure 10 is higher in Example 1 than in Comparative Example 1-2.

  In order to obtain the peel strength of the bonded structure 10 according to Example 1, a cross tensile strength test was performed. That is, a test piece (joined structure 10) having a cross-shaped planar shape as shown in FIG. 14A was manufactured under the same conditions as in Example 1. Further, as Comparative Example 1-3, a test piece was prepared in which the metal plate 11 and the resin plate 12 were bonded by an adhesive without friction stir welding so as to have a cross-shaped planar shape. In Comparative Example 1-3, the metal washer 13 is not used because it is a simple adhesion test piece. The adhesive used in Comparative Example 1-3 is a high-strength epoxy adhesive for machine structure. And the cross tensile strength test of both was done. In the cross tensile strength test, as shown in FIG. 14B, the metal plate 11 was pulled downward and the resin plate 12 was pulled upward, and the breaking load value was measured. The result is shown in FIG. FIG. 15 also shows the tensile shear strength.

In FIG. 15, the tensile shear strength and the cross tensile strength as load values are shown as measured values. Regarding the tensile shear strength, Example 1 has a smaller value than Comparative Example 1-3, which is considered to be due to the difference in the bonding area. As shown in FIG. 1, the bonding area in the first embodiment is indicated by a region where the softened portion of the metal washer 13 and the softened portion of the metal plate 11 overlap each other. This region is considered to have become circular with a diameter phi _J shown in FIG. 1, obtained as 177 mm ² from a cross-sectional photograph of FIG. 10 showing the joint structure 10 fabricated under the same conditions. The bonding area in Comparative Example 1-3 is simply the area of the region where the metal plate 11 and the resin plate 12 overlap. In the test piece for the tensile shear test, the bonding area is determined to be 750 mm ^2, and in the test piece for the cross tensile strength test, the bonding area is determined to be 2500 mm ² .

  Based on the bonding area in Example 1 and the tensile shear strength shown in FIG. 15, the tensile shear strength (corresponding to the average stress) per unit bonding area is obtained. Further, based on the joint area in Example 1 and the cross tensile strength shown in FIG. 15, a cross tensile strength (corresponding to an average stress) per unit joint area is obtained. The result is shown in FIG. FIG. 16 shows the tensile shear strength per unit bonding area and the cross tensile strength per unit bonding area according to Comparative Example 1-3 in the same manner as in Example 1.

  As shown in FIG. 16, it was confirmed that the tensile shear strength per unit bonding area and the cross tensile strength per unit bonding area were higher in Example 1 than in Comparative Example 1-3. In particular, it can be seen that the cross tensile strength per unit bonding area is significantly larger in Example 1 than in Comparative Example 1-3. Thus, in Example 1, it can be said that the peel strength of the joint structure 10 in which the metal plate 11 and the resin plate 12 are joined is greatly improved.

(Example 2)
In Example 2, the tensile shear strength was measured for the bonded structure 10 shown in FIG. That is, as Example 2-1, a test piece having a planar shape as shown in FIG. 12A without using the insulating member 50 (that is, a test piece corresponding to the joint structure 10 shown in FIG. 1). It produced and the same test piece (namely, test piece corresponded to the junction structure 10 shown in FIG. 6) using the adhesive for weld bonds to the insulating member 50 as Example 2-2 was produced. As Comparative Example 2, a similar test piece was prepared using a weld bond adhesive without friction stir welding. In Comparative Example 2, the metal washer 13 is not used because it is a simple adhesion test piece. Here, the adhesive for weld bonding used in Example 2-2 and Comparative Example 2 is an adhesive used in combination with spot welding in the automobile industry. The weld bond adhesive was applied to the second surface 11b of the metal plate 11, and also applied to the first surface 13a of the metal washer 13 in Example 2-2.

Except for the insulating member 50, the bonded structures 10 of Examples 2-1 and 2-2 were manufactured under the following conditions.
-Thickness of the metal plate 11: 1 mm
・ Thickness of resin plate 12: 1 mm
-Metal washer 13 thickness: 1 mm
Tool diameter of probe 44: 9.53 mm (3/8 inch)
-Diameter of the through hole 14 of the resin plate 12: 10 mm
Indentation depth (depth from the second surface 13b of the metal washer 13): 2.6 mm
In Comparative Example 2, the metal plate 11 having the same plate thickness as in Examples 2-1 and 2-2 and the resin plate 12 having the same plate thickness were used.

  An enlarged cross-sectional photograph of the bonded structure 10 obtained in Example 2-2 is shown in FIG. As shown in FIG. 17, even when the insulating member 50 made of a weld bond adhesive is used, the softened portion of the metal washer 13 and the softened portion of the metal plate 11 are well bonded. It could be confirmed. That is, it can be considered that the material of the insulating member 50 is not interposed between the softened portion of the metal washer 13 and the softened portion of the metal plate 11.

  A tensile shear strength test was performed on each joint structure 10 obtained in Examples 2-1 and 2-2 and Comparative Example 2. The tensile shear strength test was performed in the same manner as in Example 1. The results are shown in FIG.

  As shown in FIG. 18, Comparative Example 2 using a simple adhesive joint test piece was used rather than Example 2-1 using a test piece produced by simple friction stir welding without using an adhesive for weld bonding. However, the tensile shear strength as a load value is large, and the same tendency as in FIG. 15 is shown. Example 2-2 using a test piece produced by friction stir welding using an adhesive for weld bonds has a higher tensile shear strength than Example 2-1 and Comparative Example 2. Was confirmed. This is because in Example 2-2, the metal plate 11 and the resin plate 12 are joined with the weld bond adhesive, and the resin plate 12 and the metal washer 13 are joined with the weld bond adhesive. It can be said that the joint strength between the metal plate 11 and the resin plate 12 is increased by the synergistic effect of the joint force by the friction stir welding and the joint force by the weld bond adhesive.

(Example 3)
In Example 3, a test piece as shown in FIG. 12A (that is, a test piece corresponding to the bonded structure 10 shown in FIG. 1) was produced under the following conditions, and a tensile shear strength test was performed.
-Thickness of the metal plate 11: 1 mm
・ Thickness of resin plate 12: 1 mm
-Plate thickness of metal washer 13: 0.6 mm
-Tool diameter of probe 44: 6.35 mm (1/4 inch)
-Diameter of the through hole 14: 4 mm, 6 mm, 8 mm, 10 mm
・ Indentation depth (depth from the second surface 13b of the metal washer 13): 2.2 mm

  The tensile shear strength test was performed in the same manner as in Example 1. The results are shown in FIG.

  As shown in FIG. 19, it was confirmed that the tensile shear strength could be increased by setting the diameter of the through hole 14 to 4 mm or more. That is, according to the result shown in FIG. 19, it can be seen that the tensile shear strength can be greatly increased by setting the diameter of the through hole 14 to 4 mm or more. This is probably because the resin material of the resin plate 12 is less or less interposed between the softened portion of the metal washer 13 and the softened portion of the metal plate 11 as the diameter of the through hole 14 is larger. . In addition, when the diameter of the through hole 14 is 4 mm and 6 mm, the break at the time of the tensile shear test was the break at the friction stir joint 15, but when the diameter of the through hole 14 is 8 mm and 10 mm, The fracture at the time of the tensile shear test was the base material fracture of the resin plate 12. In the latter case, it is considered that the bonding strength at the friction stir welding portion 15 is higher than the numerical value shown in FIG.

(Example 4)
In Example 4, a test piece as shown in FIG. 12A (that is, a test piece corresponding to the bonded structure 10 shown in FIG. 1) was produced under the following conditions, and a tensile shear strength test was performed.
-Thickness of the metal plate 11: 1 mm
・ Thickness of resin plate 12: 1 mm
-Metal washer 13 thickness: 1 mm
Tool diameter of probe 44: 9.53 mm (3/8 inch)
-Diameter of the through hole 14: 3 mm, 6 mm, 10 mm, 12 mm
Indentation depth (depth from the second surface 13b of the metal washer 13): 2.6 mm

  The tensile shear strength test was performed in the same manner as in Example 1. The results are shown in FIG.

  As shown in FIG. 20, it was confirmed that the tensile shear strength can be increased by setting the diameter of the through hole 14 to 6 mm or more. That is, according to the result shown in FIG. 20, it can be seen that by setting the diameter of the through hole 14 to 6 mm or more, the tensile shear strength can be greatly increased as compared with the case where the diameter of the through hole 14 is 3 mm. Moreover, when the diameter of the through-hole 14 is 6 mm or more, the fracture | rupture at the time of a tensile shear test is a base material fracture | rupture of the resin board 12, and it is more than the numerical value shown in FIG. It is considered high.

(Example 5)
In Example 5, a test piece as shown in FIG. 12A (that is, a test piece corresponding to the bonded structure 10 shown in FIG. 1) was produced under the following conditions, and a tensile shear strength test was performed.
-Thickness of the metal plate 11: 1 mm
・ Thickness of resin plate 12: 1 mm
-Metal washer 13 thickness: 1 mm
Tool diameter of probe 44: 12.70 mm (1/2 inch)
-Diameter of the through hole 14: 3 mm, 6 mm, 10 mm, 12 mm
Indentation depth (depth from the second surface 13b of the metal washer 13): 2.6 mm

  The tensile shear strength test was performed in the same manner as in Example 1. The results are shown in FIG.

  As shown in FIG. 21, it was confirmed that the tensile shear strength can be increased by setting the diameter of the through hole 14 to 6 mm or more. That is, according to the result shown in FIG. 21, it can be seen that by setting the diameter of the through-hole 14 to 6 mm or more, the tensile shear strength can be greatly increased as compared with the case where the diameter of the through-hole 14 is 3 mm. Further, when the diameter of the through hole 14 is 6 mm or more, the fracture at the time of the tensile shear test is the base material fracture of the resin plate 12, and the bonding strength at the friction stir welding portion 15 is more than the numerical value shown in FIG. It is considered high.

(Example 6)
In Example 6, a test piece as shown in FIG. 12A (that is, a test piece corresponding to the bonded structure 10 shown in FIG. 1) was produced under the following conditions, and a tensile shear strength test was performed.
-Thickness of the metal plate 11: 2 mm
・ Thickness of resin plate 12: 1 mm
-Metal washer 13 thickness: 1 mm
Tool diameter of probe 44: 12.70 mm (1/2 inch)
-Diameter of the through hole 14: 3 mm, 6 mm, 8 mm, 10 mm, 13 mm, 14 mm
Indentation depth (depth from the second surface 13b of the metal washer 13): 3.6 mm

  The tensile shear strength test was performed in the same manner as in Example 1. The results are shown in FIG.

  As shown in FIG. 22, it was confirmed that the tensile shear strength could be increased by setting the diameter of the through hole 14 to 6 mm or more. That is, according to the result shown in FIG. 22, it can be seen that by setting the diameter of the through-hole 14 to 6 mm or more, the tensile shear strength can be greatly increased as compared with the case where the diameter of the through-hole 14 is 3 mm. Further, when the diameter of the through hole 14 is 6 mm or more, the fracture at the time of the tensile shear test is the base material fracture of the resin plate 12, and the joint strength at the friction stir weld 15 is more than the numerical value shown in FIG. It is considered high.

FIG. 23 shows a summary of the tensile shear strength test results obtained in Examples 3 to 6 described above. Here, in each example, the bonded structure 10 having a diameter of the through-hole 14 with a relatively high tensile shear strength is determined as a non-defective product (denoted as OK in FIG. 23), and the other bonded structures 10 are not used. Non-defective product (denoted as NG in FIG. 23). Then, in the graph as shown in FIG. 24, non-defective products are plotted with ◯ marks, and defective products are plotted with X marks. The vertical axis in FIG. 24 is the diameter φ _M of the through hole 14 (see FIG. 4 for both). The horizontal axis shows the predicted diameter phi _E of the through-hole 14. It will be described below with reference to FIG. 25 for the predicted diameter phi _E. Here, a case where the joining tool 42 is a spherical tool will be described.

The predicted diameter φ _E is a predicted value obtained by geometrically determining the diameter φ _M of the through hole 14 from the shape of the probe 44 of the joining tool 42 and the plate thickness of the metal plate 11, the resin plate 12 and the metal washer 13. . This prediction value is the distance from the intersection P between the second surface 12b of the wall surface and the resin plate 12 through holes 14 in the cross section shown in FIG. 25 to the curved surface 44a of the probe 44 is equal to the thickness t ₃ of the metal washer 13 It is a predicted value when it is assumed. More specifically, as shown in FIG. 25, the tool radius of the probe _{44 r (= φ T / 2} ), t 1 the thickness of the metal plate 11, the thickness of the resin plate 12 _{t 2,} metal washer 13 is the thickness t ₃ , the pressing depth of the probe 44 (depth from the second surface 13 b of the metal washer 13) is D, the tip of the probe 44 pushed into the pushing position and the first surface 11 a of the metal plate 11. The predicted radius R (= φ _E / 2) of the through hole 14 is expressed by the following equation, where d is the distance (remaining depth).

The predicted diameter φ _E (= 2 × R) of the through hole 14 can be geometrically predicted from the equations (1) and (2). The predicted diameter φ _E shown on the horizontal axis in FIGS. 23 and 24 is obtained in this way.

As shown in FIG. 24, the larger diameter phi _M of the through-hole 14 in each example it can be seen that has been determined as a good product. That is, it can be said that the tensile shear strength can be increased by increasing the diameter of the through hole 14. Further, as shown in FIG. 24, among the plotted joint structures 10, there are an area where a group of the joint structures 10 determined to be non-defective and a group of the joint structures 10 determined to be defective. It can be seen that the existing area is clearly separated. More specifically, it can be said that a non-defective product group and a defective product group are separated from each other with a straight line represented by φ _M = 0.4 × φ _E as a boundary. In the area on the side where φ _M becomes larger, there is a bonded structure 10 determined as a non-defective product.

On the other hand, the diameter phi _M of the through-hole 14, the diameter of the tool body 43 A smaller than (shoulder diameter phi _S, see FIG. 4), when the friction stir welding, the metal washer 13 in the shoulder surface 43a (especially, a metal washer 13 The softened part) can be pressed. Thus, the diameter phi _M of the through-hole 14 is preferably smaller than the shoulder diameter phi _S.

Therefore, the preferable diameter φ _M of the through hole 14 is
It can be expressed as When this formula (3) is satisfied, it can be said that the tensile shear strength can be further increased and the bonded structure 10 can be obtained in which the softened portion of the metal washer 13 is prevented from rising upward. .

Further, the welding tool 42 for the predicted diameter phi _E when a conical tool shown in FIG. 9 will be described below with reference to FIG. 26.

It predicted diameter phi _E shown in FIG. 26, the shape of the probe 44 of the welding tool 42, the metal plate 11, the thickness of the resin plate 12 and metal washer 13, to determine the diameter phi _M of the through-hole 14 geometrically It is a predicted value. This prediction value is the distance from the intersection P between the second surface 12b of the wall surface and the resin plate 12 through holes 14 in the cross section shown in FIG. 26 to the inclined surface 44c of the probe 44 is equal to the thickness t ₃ of the metal washer 13 It is a predicted value when it is assumed. More specifically, as shown in FIG. 26, the tool radius of the probe 44 (tool root radius, radius at the shoulder surface 43a) is r ₁ (= φ _T / 2), the plate thickness of the metal plate 11 is t ₁ , The plate thickness of the resin plate 12 is t ₂ , the plate thickness of the metal washer 13 is t ₃ , the push depth of the probe 44 (depth from the second surface 13b of the metal washer 13) is D, and the probe pushed into the push position The distance (remaining depth) between the tip of 44 and the first surface 11a of the metal plate 11 is defined as d. The shoulder diameter of the tool body 43 is φ _S , the radius of the distal end surface 44b of the probe 44 (the radius of the distal end of the tool) is r ₂ , and the inclined surface 44c of the probe 44 pushed into the pushing position is the second surface of the resin plate 12. 12b (or the first surface 13a of the metal washer 13) has a radius r ₃ , and the distance between the inclined surface 44c of the probe 44 pushed into the pushing position and the wall surface (intersection point P) of the through hole 14 on the second surface 12b. When r ₄ and the protruding dimension of the probe 44 are L, the predicted radius R (= φ _E / 2) of the through hole 14 is expressed by the following equation.

The predicted diameter φ _E (= 2 × R) of the through hole 14 can be geometrically predicted from the equations (4) and (5). And also when using a conical tool similarly to the case of the spherical tool mentioned above, preferable diameter (phi) _M of the through-hole 14 can be represented by Formula (3) mentioned above.

11 Metal plate 11a First surface 11b Second surface 12 Resin plate 12a First surface 12b Second surface 13 Metal washer 13a First surface 13b Second surface 14 Through hole 42 Joining tool 43 Tool body 44 Probe 44a Curved surface 44b Tip surface 44c Inclined surface 50 Insulating member dL Longitudinal direction

Claims (13)

A dissimilar material joining method for joining a joined metal member and a joined resin member using a joining metal member,
While preparing the said to-be-joined resin member which has a 1st surface, the 2nd surface provided in the opposite side to the said 1st surface, and the through-hole formed ranging from the said 1st surface to the said 2nd surface. Preparing the bonded metal member and the bonding metal member;
The to-be-joined metal member so that the through-hole of the to-be-joined resin member is covered with the to-be-joined metal member from the first surface side and is covered with the to-be-joined metal member from the second surface side. A step of superimposing the bonded resin member and the bonding metal member;
A step of pressing the joining metal member into the through-hole with a rotating joining tool and friction stir joining the metal member to be joined.   The bonding metal member has a flat first surface provided on the bonded resin member side, and a flat second surface provided on the side opposite to the first surface. The dissimilar material joining method according to claim 1.   The bonded metal member has a flat first surface provided on the side opposite to the bonded resin member, and a flat second surface provided on the bonded resin member side. The dissimilar material joining method according to claim 1 or 2.   The dissimilar material joining method as described in any one of Claims 1-3 with which the said to-be-joined metal member is formed with steel, copper, a copper alloy, an aluminum alloy, a magnesium alloy, or a titanium alloy.   The dissimilar material joining method as described in any one of Claims 1-4 with which the said to-be-joined resin member is formed with the fiber reinforced plastic material.   The dissimilar-material joining method as described in any one of Claims 1-5 with which the said to-be-joined resin member is formed with the thermosetting resin.   The dissimilar-material joining method as described in any one of Claims 1-5 with which the said to-be-joined resin member is formed with the thermoplastic resin.   In the step of superimposing the metal member to be bonded, the resin member to be bonded, and the metal member for bonding, between the metal member to be bonded and the resin member to be bonded, and the resin member to be bonded and the metal member for bonding. The dissimilar-material joining method as described in any one of Claims 1-7 by which the insulating member is each interposed in at least one between.   The dissimilar material joining method according to claim 8, wherein the insulating member is an adhesive, a sealing material, or a resin sheet.   The planar shape of the said through-hole of the said to-be-bonded resin member is a different material joining method as described in any one of Claims 1-9 which is circular. The bonded metal member has a first surface provided on the opposite side to the bonded resin member, and a second surface provided on the bonded resin member side,
The joining tool has a tool body and a spherical probe protruding from the tip of the tool body,
The tool radius of the probe is r, the thickness of the metal member to be bonded is t ₁ , the thickness of the resin member to be bonded is t ₂ , the thickness of the metal member for bonding is t ₃ , and The probe pressing depth is D, the distance between the tip of the probe pressed into the pressing position where the probe is pressed at the pressing depth D and the first surface of the bonded metal member is d, the tool When the diameter of the main body is φ _S and the radius of the through hole is R, the diameter φ _{M of the} through hole is
The dissimilar material joining method according to claim 10, wherein: The bonded metal member has a first surface provided on the opposite side to the bonded resin member, and a second surface provided on the bonded resin member side,
The joining tool has a tool body and a truncated cone-shaped probe protruding from the tip of the tool body,
The probe includes a flat tip surface, and an inclined surface whose diameter decreases from the tool body toward the tip surface,
The tool radius of the probe is r ₁ , the thickness of the metal member to be bonded is t ₁ , the thickness of the resin member to be bonded is t ₂ , the thickness of the metal member for bonding is t ₃ , and at the time of friction stir welding The probe pressing depth is D, the distance between the tip of the probe and the first surface of the metal member to be joined at the pressing position where the probe is pressed at the pressing depth D is d, The radius of the tip surface is r ₂ , the radius of the second surface of the bonded resin member of the probe pushed into the pushing position is r ₃ , and the probe pushed into the pushing position and the wall surface of the through-hole distance r ₄ in the second surface of the object to be bonded resin _members, the protruding dimension of the probe L, when the radius of the through hole was R, the diameter of the tool body and phi _S, the diameter of the through hole φ _M is
The dissimilar material joining method according to claim 10, wherein:   The planar shape of the said through-hole of the said to-be-joined resin member is a different material joining method as described in any one of Claims 1-9 which has a longitudinal direction.