JP6330760B2 - Method of joining metal member and resin member - Google Patents

Description

  The present invention relates to a method for joining a metal member and a resin member, a joined body, and a joining apparatus.

  Conventionally, weight reduction is required in the fields of automobiles, railway vehicles, airplanes, and the like. For example, in the field of automobiles, the use of high-tensile materials has made it possible to make steel sheets thinner, aluminum alloy materials have been used as substitutes for steel materials, and resin materials have also been increasingly used. In these fields, development of joining technology for metal members and resin members is important not only for reducing the weight of the car body, but also for increasing the strength and rigidity of the joining members and improving productivity. is there. So far, a so-called friction stir welding (FSW) method has been proposed as a method for joining a metal member and a resin member. The friction stir welding method is a method in which a metal member and a resin member are overlapped, a rotating tool is rotated and pressed against the metal member to generate frictional heat. After the resin member is melted by this frictional heat, the resin member is solidified. The metal member and the resin member are joined together.

  In such a friction stir welding method, for example, a technique (Patent Document 1) is disclosed in which the shape and push-in amount of the rotary tool are set within a specific range from the viewpoint of joining strength and simple joining.

  On the other hand, a technique for improving the strength of a resin member by adding a reinforcing fiber to the resin member is known.

JP 2010-158885 A

  However, in the conventional friction stir welding method, when a resin member containing reinforcing fibers is used, the bonding strength may be reduced.

  The inventors of the present invention have intensively studied the phenomenon of such a decrease in bonding strength, and as a result, have found that the phenomenon is caused by springback of reinforcing fibers contained in the resin member. Specifically, as shown in FIG. 9A, the pressing member 216 is pushed into the metal member 211, and the region 221 directly below the pressing member of the resin member 212 and its outer peripheral region are melted by frictional heat, and then solidified. As a result, springback occurred in the melted and solidified region of the resin member 212. The spring back is a phenomenon in which the curved reinforcing fiber is released from the restraining force when the resin member 212 is melted and deforms so as to return straight. When such a springback occurs, as shown in FIG. 9B, bubbles are mixed in the melt-solidified region of the resin member 212, and a bubble layer that appears to be foamed (so-called springback layer). 222 is formed, and it is considered that the bonding strength is lowered by the occurrence of the intra-layer fracture in the bubble layer 222 having a low strength.

  Therefore, the inventors examined various attempts to prevent the formation of the bubble layer, and it was necessary to use a special resin member or to perform special cooling, which was very complicated.

  The present invention provides a method for joining a metal member and a resin member, which can easily achieve joining of the resin member and the metal member with sufficient strength even when the reinforcing fiber is contained in the resin member. The purpose is to do.

The present invention includes the following preferred embodiments.
[1] A metal member and a resin member containing reinforcing fibers are superposed, pressure is applied to the resin member by pressing from the metal member side by the pressing member, and heat is applied to soften and melt the resin member. Then, a method of joining the metal member and the resin member by a hot-pressure joining method that solidifies and joins,
The joining method of a metal member and a resin member which joins so that a bubble layer may be formed in the thickness below 1 mm on the metal member side surface of the fusion | melting solidification area | region in the said resin member.
[2] The metal member and resin according to [1], wherein driving of the pressing member and application of heat are controlled so that a bubble layer is formed with the thickness on the metal member side surface of the melt-solidified region in the resin member. Joining method with member.
[3] The hot-pressure bonding method includes:
A first step of superimposing the metal member and the resin member; and, while rotating the rotary tool as the pressing member, pressing the metal member to generate frictional heat, softening and melting the resin member by the frictional heat, A friction stir welding method including a second step of solidifying and joining the metal member and the resin member;
The metal member and the resin member according to [1] or [2], wherein driving of the rotary tool is controlled so that a bubble layer is formed with the thickness on the metal member side surface of the melted and solidified region in the resin member. Joining method.
[4] The method for joining the metal member and the resin member according to [3], wherein pressing and / or rotational driving of the rotary tool is controlled.
[5] Adopting a pressure control method in the second step,
The method for joining the metal member and the resin member according to [3] or [4], wherein the pressing force and pressurizing time and the number of rotations of the rotating tool on the metal member are controlled.
[6] The second step includes
A preheating step of rotating the rotary tool in a state where only the tip of the rotary tool is in contact with the surface of the metal member;
A pushing agitation step of pushing the rotating tool into the metal member and entering the metal member and the resin member to a depth not reaching the joining boundary surface; and a position where the rotating tool is entered in the pushing agitation step. Including an agitation maintaining step for continuing the rotation operation,
In the preheating step, the rotary tool is rotated by the first pressurizing time while being pressed with the first pressurizing force,
In the indentation stirring step, the rotary tool is rotated by a second pressurization time shorter than the first pressurization time while pressing the rotary tool with a second pressurization force larger than the first pressurization force,
In the stirring maintaining step, the rotary tool is rotated by a third pressurizing time longer than the first pressurizing time while pressing the rotating tool with a third pressurizing force smaller than the first pressurizing force. A method of joining a metal member and a resin member.
[7] In the preheating step, the first pressure is adjusted in a range of 600 N or more and less than 1300 N, and the first pressurizing time is adjusted in a range of 0.5 second or more and less than 2.0 seconds,
In the indentation stirring step, the second pressure is adjusted in the range of 1300 N or more and less than 2200 N, the second pressurizing time is adjusted in the range of 0.1 second or more and less than 0.5 second,
In the stirring maintaining step, the third pressure is adjusted in a range of 100 N or more and less than 1200 N, and the third pressurizing time is adjusted in a range of 2.0 seconds or more and less than 8.5 seconds, [6]. Joining method of metal member and resin member.
[8] The metal member and the resin member according to [7], wherein in the preheating step, the indentation stirring step, and the stirring maintaining step, the number of rotations of the rotary tool is independently adjusted in a range of 2000 rpm to 4000 rpm. Joining method.
[9] A position control method is adopted in the second step,
The method for joining the metal member and the resin member according to [3] or [4], wherein the coordinate position of the rotary tool, the holding time at the specific position, and the number of rotations are controlled.
[10] The second step includes
Including a pushing agitation step of pushing the rotating tool into the metal member to enter a depth that does not reach the joining interface between the metal member and the resin member;
The metal member according to [9], wherein the rotating tool is caused to enter the metal member up to an entry amount of 0.4 × T to 0.9 × T, where T is a thickness of the metal member in the indentation stirring step. And joining method of resin member.
[11] The second step further includes
A stirring maintaining step of continuing the rotating operation of the rotating tool at a position where the rotating tool is entered in the indentation stirring step;
Including
In the stirring maintaining step, the rotating tool is held at a position where the rotating tool is entered in the indenting stirring step for not less than 2.0 seconds and less than 8.5 seconds,
The joining method of the metal member and the resin member according to [10], wherein the rotating tool is allowed to enter at an approach speed of 0.05 to 1 mm / second in the indentation stirring step.
[12] The metal member and the resin member according to [10] or [11], wherein the number of rotations of the rotating tool is independently adjusted in a range of 2000 rpm to 4000 rpm in the indentation stirring step and the stirring maintaining step. Joining method.
[13] The method for joining the metal member and the resin member according to any one of [1] to [12], wherein a thickness T of the metal member is 0.5 to 4 mm.
[14] The metal member is made of aluminum or an aluminum alloy,
The method for joining a metal member and a resin member according to any one of [1] to [13], wherein the resin member has a melting point Tm of 130 to 350 ° C.
[15] The rotating tool has a pin portion projecting on a central axis of the rotating tool and a shoulder portion supporting the pin portion at a tip portion in contact with the metal member, and the shoulder portion has a mortar shape. The method for joining a metal member and a resin member according to any one of [3] to [14], wherein the metal member has an inclined surface that is recessed.
[16] The method for joining a metal member and a resin member according to any one of [1] to [15], wherein an average fiber length L of the reinforcing fibers is more than 1 mm and not more than 50 mm.
[17] The joining of the metal member and the resin member according to any one of [1] to [16], wherein the resin member contains the reinforcing fiber in a proportion of 10 to 50% by weight with respect to the total amount of the resin member. Method.
[18] The resin member according to any one of [1] to [17], wherein the resin member is produced by subjecting a mixture containing a thermoplastic polymer and a reinforcing fiber to an injection molding method or a press molding method. A method of joining a metal member and a resin member.
[19] The method for joining a metal member and a resin member according to any one of [1] to [18], wherein the solidification is performed by standing cooling.
[20] A joined body in which a metal member and a resin member containing reinforcing fibers are joined by melting and solidifying a part of the resin member,
A bonded body of a metal member and a resin member, wherein the metal member has a bubble layer having a thickness of 1 mm or less on a surface on the metal member side of a melt-solidified region in the resin member.
[21] A joined body of the metal member and the resin member according to [20], which is joined by the joining method of the metal member and the resin member according to any one of [1] to [19].
[22] The metal member and the resin member containing the reinforcing fiber are superposed, pressure is applied to the resin member by pressing from the metal member side by the pressing member, and the resin member is softened and melted by heat and then solidified. It is a joining device between a metal member and a resin member by a hot-pressure joining method that performs joining,
An apparatus for joining a metal member and a resin member, including a drive control device for controlling the drive of the pressing member so that a bubble layer is formed with a thickness of 1 mm or less on the surface of the melted and solidified region of the resin member on the metal member side.
[23] A joining apparatus for joining a metal member and a resin member according to [22] for carrying out the joining method for a metal member and a resin member according to any one of [1] to [19].

  According to the joining method of the present invention, even if the reinforcing fiber is contained in the resin member, the joining of the resin member and the metal member can be easily achieved with sufficient strength. Moreover, the joining method of this invention does not need to use a special resin member or to perform special cooling.

It is a schematic diagram which shows an example of a part of friction stir welding apparatus suitable for the joining method of the metal member and resin member concerning this invention. It is an enlarged view of the front-end | tip part of an example of the rotation tool as a press member used for the joining method of this invention. It is an enlarged view of the front-end | tip part of another example of the rotation tool as a pressing member used for the joining method of this invention. It is a schematic sectional drawing for demonstrating an example of the preheating process of this invention. It is a schematic sectional drawing for demonstrating an example of the pushing stirring process and stirring stirring process of this invention. It is a schematic diagram which shows the surface state of the resin member when a metal member is forcedly peeled from the joining body obtained by the joining method of this invention, and the metal member side surface of the resin member is observed. It is an enlarged view of the joining boundary surface of the metal member and the resin member in the joined body obtained by the joining method of the present invention. It is the schematic for demonstrating the measuring method of the joint strength in an Example. (A) is a schematic sectional drawing for demonstrating the joining method of the metal member and resin member in a prior art, (B) is the metal member and resin member in the joined_body | zygote obtained by the method of (A). It is an enlarged view of the joining boundary surface.

  In the joining method of the present invention, after a metal member and a resin member are overlapped, pressure is applied to the resin member by pressing from the metal member side by the pressing member, and heat is applied to soften and melt the resin member. This is a hot-pressure joining method in which a metal member and a resin member are joined by solidification. Heat and pressure are preferably applied locally. The hot-pressure bonding method of the present invention is a method of applying heat by a pressing member or another means while applying pressure by the pressing member. As will be described later, in the hot-pressure bonding method, bonding is performed so that a bubble layer is formed on the metal member side surface of the melt-solidified region of the resin member with a thickness within a predetermined range in the bonded body of the metal member and the resin member. The method is not particularly limited as long as it can be performed. For example, a friction stir welding method, an ultrasonic heating bonding method, a laser heating bonding method, a resistance heating bonding method, an induction heating bonding method, or the like may be used. Preferably, it is a method in which heat and pressure are locally applied from the metal member side by a pressing member, and a friction stir welding method is more preferably employed.

  The joining is performed so that the bubble layer is formed with a thickness within a predetermined range. As will be described in detail later, the pressure member is driven and heated so that the thickness of the bubble layer is within a predetermined range. In other words, in the friction stir welding method, the drive of the rotary tool is controlled.

  As will be described in detail later, the friction stir welding method is a method in which a metal member and a resin member are overlapped and a rotating tool as a pressing member is rotated to press the metal member to generate frictional heat. In this method, the resin member is softened and melted by heat and then solidified to join the metal member and the resin member.

  The ultrasonic heating bonding method is to superimpose a metal member and a resin member, press the metal member with the pressing member, and cause ultrasonic vibration to the pressing member and the metal member with ultrasonic waves (heat applying means), In this method, the resin member is softened and melted by the frictional heat of the resin member / metal member generated by vibration and then solidified to join the metal member and the resin member.

  The laser heating bonding method is a method in which a metal member and a resin member are overlapped and heat is generated by irradiating a metal member with a laser (heat applying means) in a state where the metal member and the resin member are constrained by pressurization by a pressing member. In this method, the resin member is softened and melted by heat and then solidified to join the metal member and the resin member. As the laser, a YAG laser, a fiber laser, a semiconductor laser, or the like is used.

  The resistance heating bonding method uses heat generated by flowing a current (heat applying means) directly to a metal member in a state where the metal member and the resin member are overlapped and constrained by pressurization by the pressing member. The resin member is softened and melted and then solidified to join the metal member and the resin member.

  The induction heating joining method is a method in which a metal member and a resin member are overlapped, and an induction current (heat applying means) is generated in the metal member by electromagnetic induction in a state in which the metal member and the resin member are constrained by pressurization by the pressing member. In this method, the resin member is softened and melted using heat generated by an electric current and then solidified to join the metal member and the resin member.

  Hereinafter, the joining method of the present invention employing the friction stir welding method will be described in detail with reference to the drawings. However, a bubble layer is formed with a thickness within a predetermined range on the metal member side surface of the melt-solidified region in the resin member. As long as bonding is performed in this way, it is apparent that the effects of the present invention can be obtained even if other bonding methods described above are used. It should be noted that the various elements shown in the drawings are merely schematically shown for understanding of the present invention, and the dimensional ratio, appearance, and the like may differ from the actual ones. The “vertical direction” used directly or indirectly in this specification corresponds to a direction corresponding to the vertical direction in the drawing. Unless otherwise specified, in these drawings, common reference numerals indicate the same members, parts, dimensions, or regions.

[Method of joining metal member and resin member by friction stir welding method]
The joining method (friction stir welding method) of the present invention will be specifically described with reference to FIGS.

(1) Joining Device First, FIG. 1 is a diagram schematically showing an example of a part of a friction stir welding device suitable for carrying out the joining method of the present invention. A friction stir welding apparatus 1 shown in FIG. 1 is configured as a device for friction stir welding a metal member 11 and a resin member 12, and includes a columnar rotary tool 16 as a pressing member.

  As shown in the figure, the rotary tool 16 is applied to the workpiece 10 with the metal member 11 on the top and the resin member 12 on the bottom, by a drive source (not shown) as indicated by an arrow A1. While rotating around the central axis X (see FIG. 2), it moves downward as indicated by an arrow A2. At this time, the rotary tool 16 applies pressure in the pressing region P (scheduled pressing region) on the surface of the metal member 11. Friction heat is generated by the pressing of the rotary tool 16, and the friction heat is conducted to the resin member 12 to soften and melt the resin member 12, and then the molten resin is solidified. As a result, the metal member 11 and the resin member 12 are joined.

  FIG. 2 is an enlarged view of the tip portion of an example of the rotary tool 16. In FIG. 2, the right half shows the appearance of the rotary tool 16, and the left half shows a cross section. As shown in FIG. 2, the columnar rotary tool 16 has a pin portion 16 a and a shoulder portion 16 b that supports the pin portion at a distal end portion (lower end portion in FIG. 2) that contacts the metal member. The shoulder portion 16 b is a portion at the tip of the rotary tool 16 including the circular tip surface of the rotary tool 16. The pin portion 16a is a cylindrical portion having a smaller diameter than the shoulder portion 16b, which protrudes outwardly (downward in FIG. 2) from the circular tip surface of the rotary tool 16 on the central axis X of the rotary tool 16. is there. The pin portion 16a is for positioning the rotating tool 16 when the rotating tool 16 that is rotating is first brought into contact with the workpiece 10 and pressed.

  The material of the rotary tool 16 and the dimensions of each part are mainly set according to the metal type of the metal member 11 pressed by the rotary tool 16. For example, when the metal member 11 is made of an aluminum alloy, the rotary tool 16 is made of tool steel (for example, SKD61), the diameter D1 of the shoulder portion 16b is 10 mm, the diameter D2 of the pin portion 16a is 2 mm, and the pin portion 16a protrudes. The length h is set to 0.5 mm. For example, when the metal member 11 is made of steel, the rotary tool 16 is made of silicon nitride, PCBN (cubic boron nitride sintered body) or the like, the diameter D1 of the shoulder portion 16b is 10 mm, and the diameter D2 of the pin portion 16a. Is set to 3 mm, and the protruding length h of the pin portion 16a is set to 0.5 mm. Needless to say, these are merely examples, and the present invention is not limited thereto.

  A rotary tool 16 'shown in FIG. 3 may be used. FIG. 3 is an enlarged view of a tip portion of another example of the rotary tool. In FIG. 3, the rotary tool 16 ′ is the same as the rotary tool 16 of FIG. 2 except that the shoulder portion 16 b has an inclined surface 16 c that is recessed in a mortar shape (conical shape). In FIG. 3, the depth of the recess becomes deeper as it approaches the pin portion 16a from the outer periphery of the shoulder portion 16b. As a result, the shoulder portion 16b of the rotary tool 16 ′ comes into contact with the metal member from the outer peripheral portion at the time of joining, so that the maximum diameter of the melt-solidified region to be described later can be expanded, and further improvement in joining strength can be achieved. . The inclination angle θ of the inclined surface 16c is usually 15 ° or less, preferably 1 to 15 °, more preferably 5 to 10 °.

  Below the rotary tool 16, a cylindrical receiving member 17 having the same diameter as the rotary tool 16 or a larger diameter than the rotary tool 16 is arranged coaxially with the rotary tool 16. The receiving member 17 is moved upward with respect to the work 10 as shown by an arrow A3 by a driving source (not shown). The upper end surface of the receiving member 17 abuts on the lower surface of the workpiece 10 (more specifically, the lower surface of the resin member 12) by the time the rotating tool 16 starts pressing the workpiece 10 at the latest. The support 17 sandwiches the workpiece 10 between the rotary tool 16 and supports the workpiece 10 from below against the pressing force during a pressing period by the rotary tool 16, that is, during friction stir welding. Note that the receiving tool 17 does not necessarily have to be moved in the direction of the arrow A3, and a method of moving the rotary tool 16 in the direction of the arrow A2 after placing the workpiece 10 on the receiving tool 17 can also be adopted.

  The friction stir welding apparatus 1 rotates as a pressing member so that a bubble layer is formed with a thickness within a predetermined range on the metal member side surface of the melt-solidified region of the resin member in the joined body of the metal member and the resin member. A drive control device (not shown) for controlling the drive of the tool, in particular the press drive and / or the rotary drive, preferably the press drive and the rotary drive is included.

  As will be described in detail later, the drive control device may employ a pressure control method for controlling the pressing force and pressurizing time and the number of rotations on the metal member of the rotary tool, or the coordinate position of the rotary tool, You may employ | adopt the position control system which controls the holding time and rotation speed in a specific position.

  Although not shown in FIG. 1, the friction stir welding apparatus 1 uses a spacer, a clamp, or the like for fixing the work 10 in advance and preventing the metal member 11 from floating when the rotary tool 16 is pressed. A jig is provided.

(2) Joining Method According to the joining method of the present invention, the melted and solidified region 61 (see FIG. 6; hatched region) is formed by melting and solidifying the resin member 12 at the interface 13 between the metal member 11 and the resin member 12. The melt-solidified region 61 contributes to the joining between the metal member 11 and the resin member 12. In the present invention, bonding is performed so that the bubble layer 62 (see FIG. 6; lattice region) is formed with a predetermined thickness on the surface of the melt-solidified region 61 on the metal member side. Specifically, the bonding is performed so that the thickness of the bubble layer 62 formed on the metal member side surface in the melt-solidified region 61 of the resin member 12 is 1 mm or less. Thereby, joining of a resin member and a metal member can be achieved simply and with sufficient strength. In the bonding method of the present invention, when the heat input is reduced to a condition where no bubble layer is formed, the melt-solidified region becomes too small, and sufficient bonding strength may not be obtained. On the other hand, even when bonding is performed under a condition where the thickness of the bubble layer exceeds 1 mm, sufficient bonding strength cannot be obtained.

  In the present invention, the thickness of the bubble layer is affected by the amount of heat input in each step described later. For example, the greater the amount of heat input, the greater the thickness of the bubble layer. Further, for example, the smaller the heat input amount, the thinner the bubble layer tends to be.

The method of joining the metal member and the resin member by the friction stir welding method according to the present invention is at least the following steps:
A first step of superimposing the metal member 11 and the resin member 12; and while rotating the rotary tool 16, the metal member 11 is pressed to generate frictional heat, and the resin member 12 is softened and melted by the frictional heat. Then, the second step of solidifying and joining the metal member 11 and the resin member 12:
Is included.

  In the first step, as shown in FIG. 1, the metal member 11 and the resin member 12 are overlapped at a desired joint portion.

  In the second step, the driving of the rotating tool is controlled so that the thickness of the bubble layer is within a predetermined range. In the second step, as described above, the pressure control method for controlling the pressurizing force, pressurizing time, and rotational speed of the rotary tool, or the coordinate position of the rotary tool, the holding time at the specific position, and the position for controlling the rotational speed. Adopt control method. Hereinafter, the second step employing the pressure control method will be described as the first embodiment, and the second step employing the position control method will be described as the second embodiment.

<First Embodiment: Pressure Control Method>
In the second step of the present embodiment, at least the pushing and stirring step C <b> 2 for pushing the rotary tool 16 into the metal member 11 and entering to a depth that does not reach the joining boundary surface 13 between the metal member 11 and the resin member 12 is performed. preferable.

  In the second step of the present embodiment, a preheating step C1 for rotating the rotary tool 16 in a state where only the front end portion of the rotary tool 16 is in contact with the surface portion of the metal member 11 is performed before the pushing and stirring step. Although preferred, it is not necessary.

  After the indentation stirring step, it is preferable to perform an agitation maintenance step C3 in which the rotation operation of the rotation tool 16 is continued at a position where the rotation tool 16 has entered in the indentation agitation step, but this step must also be performed. Not that.

  Hereinafter, these steps in this embodiment will be described in detail.

(Preheating process C1)
In the preheating step C1, by bringing the rotary tool 16 and the receiving member 17 close to each other, as shown in FIG. 4, only the tip of the rotary tool 16 is placed on the surface portion (upper surface portion in the illustrated example) of the metal member 11. This is a step of rotating the rotary tool 16 in a contacted state. In the preheating step C1, the rotary tool 16 is rotated at a predetermined rotation speed (for example, 3000 rpm) for a first pressurizing time (for example, 1.00 seconds) with a first pressure (for example, 900 to 1200 N). Let 4 is a schematic cross-sectional view of the XX cross section in FIG. 1 as viewed in the direction of the arrow.

  Specifically, in the preheating step C <b> 1, frictional heat is generated at the surface portion (upper surface portion in the illustrated example) of the metal member 11 by pressing of the rotary tool 16. The frictional heat is transmitted to the inside of the metal member 11, and the range of the pressing area P (the pressing area by the rotary tool 16) of the metal member 11 and the area near the pressing area P are preheated. Thereby, it becomes easy to push the rotary tool 16 into the metal member 11 in the next pushing and stirring step C2.

  The first pressurizing step and the first pressurizing time in the preheating step C1 are the viewpoint of the thickness of the bubble layer, the viewpoint of ease of pushing in the rotary tool 16 as described above, and the ease of softening and melting of the resin member 12. In addition, the value is set from the viewpoint of productivity, and the value varies depending on, for example, the number of rotations of the rotary tool 16, the thickness of the metal member 11, the type of material, the melting point of the resin member 12, and the like. For example, when using an aluminum alloy metal member 11 having a thickness of 1 mm or more and 2 mm or less and a resin member 12 having a melting point described later, the first pressure in the preheating step C1 is preferably 600 N or more and less than 1300 N. The first pressurization time is preferably 0.5 seconds or more and less than 2.0 seconds. The rotation speed of the rotary tool is preferably 2000 rpm or more and 4000 rpm or less.

  The amount of heat input in this step is determined by the magnitude of the first applied pressure, the length of the first pressurizing time, and the magnitude of the rotational speed of the rotary tool.

(Indentation stirring step C2)
In the indentation stirring step C2, the rotary tool 16 and the receiving member 17 are brought close to each other, thereby pushing the rotary tool 16 into the metal member 11 as shown in FIG. When the pushing and stirring step C2 is performed after the preheating step C1, the rotating tool 16 and the receiving member 17 are brought closer to each other, thereby pushing the rotating tool 16 into the metal member 11 as shown in FIG. Thereby, the rotary tool 16 is advanced to a depth that does not reach the joint boundary surface 13 between the metal member 11 and the resin member 12. At this time, it is preferable that the lower portion 110 of the metal member 11 is protruded and deformed toward the resin member 12 as shown in FIG. Thereby, about the molten resin 120 of the resin member surface melt | dissolved in the area | region immediately under a rotating tool, the fusion | melting and the flow (arrow direction of FIG. 5) to the outer peripheral area | region can be accelerated | stimulated. FIG. 5 is a schematic cross-sectional view of the XX cross section in FIG.

  Specifically, in the indentation stirring step C2, the rotary tool 16 is moved at a second pressurization time (second pressure greater than the first pressurization (eg, 1500 N to 2000 N) and shorter than the first pressurization time ( For example, the rotation is performed at a predetermined rotation speed (for example, 3000 rpm) for 0.25 seconds.

  In the indentation stirring step C2, the rotating tool 16 is pushed into the metal member 11 when the applied pressure is larger than that in the preheating step C1. That is, the rotary tool 16 enters deep inside the metal member 11. Preferably, when the rotary tool 16 is pressed, the joining boundary surface 13 between the metal member 11 and the resin member 12 moves to the support 17 side (lower side in the illustrated example) in the lower portion 110 of the metal member 11. The right lower part 110 projects and deforms toward the resin member 12 side. By the indentation stirring step C2 and the stirring maintaining step C3 that is preferably performed thereafter, the melting of the molten resin 120 on the surface of the resin member melted in the region immediately below the rotary tool at the joining interface 13 is promoted, and the region immediately below And flows to the outer peripheral region (in the direction of the arrow in FIG. 5). The molten resin spreads in a substantially circular shape centering on the region directly under the rotary tool. As a result, the contact area between the molten resin and the metal member 11 is expanded, and the melted and solidified region (bonded region) obtained by solidifying the molten resin by cooling in the obtained bonded body is also expanded. Can be achieved with sufficiently good working efficiency and sufficient strength.

  If the rotary tool 16 is further pushed in (that is, if the applied pressure is too high and / or the pressurizing time is too long), the shoulder portion 16b of the rotary tool 16 exceeds the joining boundary surface. That is, the rotary tool 16 penetrates the metal member 11, and the outer peripheral portion of the rotary tool 16 contacts the resin member 12. Then, the metal member 11 is in a holed state in which the hole through which the rotary tool 16 has passed is opened, resulting in poor bonding.

  Therefore, in this indentation stirring step C2, the indentation of the rotation tool 16 is stopped when the shoulder portion 16b of the rotation tool 16 enters a depth that does not reach the joint boundary surface. In other words, the rotary tool 16 is advanced to a depth that does not reach the joint interface. As a result, in the next agitation maintaining step C3, frictional heat is generated at a reference position close to the resin member 12, a large amount of frictional heat is transmitted to the resin member 12, and softening and melting of the resin member 12 are promoted.

  The second pressing force and the second pressurizing time in the indentation stirring step C2 are set from the viewpoint of avoiding the opening of the metal member 11 as described above and the rotating tool 16 as close to the resin member 12 as possible. The value varies depending on, for example, the number of rotations of the rotary tool 16, the thickness of the metal member 11, the type of material, the melting point of the resin member 12, and the like. For example, when the aluminum alloy metal member 11 having a thickness of 1 mm or more and 2 mm or less and a resin member 12 having a melting point described later are used, the second applied pressure in the indentation stirring step C2 is preferably 1300 N or more and less than 2200 N. The second pressurization time is preferably 0.1 seconds or more and less than 0.5 seconds. The rotation speed of the rotary tool is preferably 2000 rpm or more and 4000 rpm or less.

  The amount of heat input in this step is determined by the magnitude of the second applied pressure, the length of the second pressurizing time, and the magnitude of the rotational speed of the rotary tool.

(Stirring maintenance step C3)
The agitation maintaining step C3 stops the mutual approach between the rotary tool 16 and the receiving member 17 and, as shown in FIG. This is a step of continuing the rotation operation of the rotary tool 16 at the “position”). In the agitation maintaining step C3, the rotary tool 16 is moved to a third pressurization time (for example, 2 to 2) longer than the first pressurization time with a third pressurization force (for example, 500 to 800 N) smaller than the first pressurization force. .75 to 6.75 seconds) at a predetermined rotation speed (for example, 3000 rpm). In particular, the third pressurizing time is set to a time that does not cause the bubble layer to become too thick.

  In the stirring maintaining step C3, the rotating tool 16 is substantially maintained at the reference position by the applied pressure being smaller than that of the preheating step C1 (of course, being smaller than the pushing stirring step C2). Since the rotary tool 16 continues to rotate at the reference position close to the resin member 12, a large amount of frictional heat is generated, and most of the generated frictional heat moves to the resin member 12. Therefore, the resin member 12 is sufficiently softened and melted in a wide range beyond the range just below the pressing region P.

  The third pressing force and the third pressurizing time in the stirring maintaining step C3 are from the viewpoint of the thickness of the bubble layer, and from the viewpoint of sufficient softening / melting and productivity in a wide range of the resin member 12 as described above. The value is set and varies depending on, for example, the number of rotations of the rotary tool 16, the thickness of the metal member 11, the type of material, and the melting point of the resin member 12. For example, when the aluminum alloy metal member 11 having a thickness of 1 mm or more and 2 mm or less and a resin member 12 having a melting point described later are used, the third pressure in the stirring and maintaining step C3 is preferably 100 N or more and less than 1200 N. The third pressurization time is preferably 2.0 seconds or more and less than 8.5 seconds. The rotation speed of the rotary tool is preferably 2000 rpm or more and 4000 rpm or less.

The amount of heat input in this step is determined by the magnitude of the third pressing force, the length of the third pressurizing time, and the magnitude of the rotational speed of the rotary tool.
In particular, the longer the third pressurization time is within the above range, the greater the thickness of the bubble layer. The shorter the third pressurization time is within the above range, the smaller the thickness of the bubble layer.

  In the present embodiment, after the stirring and maintaining step C3 is performed, the solidification is usually performed by allowing to cool by standing. That is, it is solidified without forcibly cooling from the outside.

<Second Embodiment: Position Control Method>
Also in the second step of the present embodiment, at least the pushing and stirring step C <b> 2 for pushing the rotary tool 16 into the metal member 11 and entering it to a depth that does not reach the joint boundary surface 13 between the metal member 11 and the resin member 12 is performed. preferable.

  In the second step of the present embodiment, a preheating step C1 for rotating the rotary tool 16 in a state where only the tip portion of the rotary tool 16 is in contact with the surface portion of the metal member 11 is performed before the indentation stirring step. However, since the position control method is adopted, it may not be performed.

  After the indentation stirring step, it is preferable to perform an agitation maintenance step C3 in which the rotation operation of the rotation tool 16 is continued at a position where the rotation tool 16 has entered in the indentation agitation step, but this step must also be performed. Not that.

  Hereinafter, these steps in this embodiment will be described in detail.

(Indentation stirring step C2)
The pushing and stirring step C2 of this embodiment is the same as the pushing and stirring step C2 of the first embodiment, except that a position control method is adopted. Specifically, in the indentation stirring step C2 of the present embodiment, as shown in FIG. 5, the rotating tool 16 is rotated at a predetermined number of rotations (for example, 3000 rpm) and a predetermined depth (for example, the thickness of the metal member). Is set to 0.5 × T to 0.9 × T, where T is (mm).

  In the indentation agitation step C2, the joint interface 13 between the metal member 11 and the resin member 12 is placed on the support 17 side (see FIG. In the example, it moves to the lower side), and the immediate lower part 110 projects and deforms toward the resin member 12 side. As a result, as in the indentation stirring step C2 of the first embodiment, the melting of the molten resin 120 on the surface of the resin member melted in the region immediately below the rotary tool at the joining interface 13 is promoted, and the region immediately below And flows to the outer peripheral region (in the direction of the arrow in FIG. 5). The molten resin spreads in a substantially circular shape centering on the region directly under the rotary tool. As a result, the contact area between the molten resin and the metal member 11 is expanded, and the melted and solidified region (bonded region) obtained by solidifying the molten resin by cooling in the obtained bonded body is also expanded. Can be achieved with sufficiently good working efficiency and sufficient strength.

  When the rotary tool 16 enters a predetermined depth, the pushing movement of the rotary tool 16 is stopped.

  The amount of entry (intrusion depth) of the rotary tool in the indentation stirring step C2 is set from the viewpoint of bringing the rotary tool 16 as close as possible to the resin member 12, and the values thereof are, for example, the number of rotations of the rotary tool 16 and the thickness of the metal member 11. It varies depending on the type of material and the melting point of the resin member 12. For example, when using an aluminum alloy metal member 11 having a thickness of 1 mm or more and 2 mm or less and a resin member 12 having a melting point described later, the amount of intrusion of the rotary tool in the indentation stirring step C2 is defined as T (mm). In this case, 0.4 × T to 0.9 × T (mm), preferably 0.5 × T to 0.9 × T (mm). The amount of entry is the depth of entry in the thickness direction from the surface of the metal member. The rotation speed of the rotary tool is preferably 2000 rpm or more and 4000 rpm or less.

  The amount of heat input in this step is determined by the entry time of the rotating tool and the number of rotations of the rotating tool, and the entry time of the rotating tool is determined by the amount of entry and the entry speed of the rotating tool.

  In this step, the approach speed of the rotary tool is not particularly limited, and is preferably 0.05 to 1 mm / second, particularly 0.1 to 0.5 mm / second.

(Stirring maintenance step C3)
The agitation maintaining step C3 of this embodiment is the same as the agitation maintaining step C3 of the first embodiment except that no pressure is applied to the metal member in order to adopt the position control method. Without applying pressure to the metal member 11 by the rotating tool 16, as shown in FIG. 5, the rotating operation of the rotating tool 16 is continued at the position where the rotating tool 16 is entered in the pushing and stirring step C2. Thereby, a large amount of frictional heat is generated, and most of the generated frictional heat moves to the resin member 12. Therefore, the resin member 12 is sufficiently softened and melted in a wide range beyond the range just below the pressing region P.

  In the agitation maintaining step C3, the rotary tool 16 is rotated at a predetermined rotational speed (for example, 3000 rpm) while holding the rotary tool 16 at the predetermined position for a predetermined time (for example, 3 to 8 seconds). In particular, the holding time is set to such a time that the thickness of the bubble layer does not become too thick.

  The holding time of the stirring and maintaining step C3 is set from the viewpoint of the thickness of the bubble layer and from the viewpoint of sufficient softening / melting and productivity in a wide range of the resin member 12 as described above. 16 changes depending on the number of rotations, the thickness of the metal member 11, the type of material, the melting point of the resin member 12, and the like. For example, when the aluminum alloy metal member 11 having a thickness of 1 mm or more and 2 mm or less and a resin member 12 having a melting point described later are used, the holding time in the stirring and maintaining step C3 is preferably 0 second or more and less than 8.5 seconds. The rotation speed of the rotary tool is preferably 2000 rpm or more and 4000 rpm or less. The holding time of 0 seconds means that the stirring and maintaining step C3 may not be performed in this embodiment. This is because the amount of heat input can be adjusted only by the entry time of the rotary tool in the indentation stirring step C2. In particular, when the amount of approach, the approach speed, and the rotational speed of the rotary tool are within the above ranges in the indentation stirring step C2, the holding time in the stirring maintaining step C3 is usually 2 seconds or more and less than 8.5 seconds.

The amount of heat input in this step is determined by the length of the holding time and the rotation speed of the rotating tool.
In particular, the longer the holding time is within the above range, the greater the thickness of the bubble layer. The shorter the holding time is within the above range, the smaller the thickness of the bubble layer.

  Also in this embodiment, after performing the stirring and maintaining step C3, solidification is usually achieved by cooling by standing. That is, it is solidified without forcibly cooling from the outside.

(3) Metal Member The metal member 11 used in the present invention has a substantially flat plate shape as an overall shape in FIG. 1 and the like, but is not limited to this, and at least overlaps with the resin member 12. As long as the portion has a substantially flat plate shape, it may have any shape. The part of the metal member 11 that overlaps with the resin member 12 is generally composed of a flat surface on both sides.

  The thickness T (thickness before the bonding treatment; see FIG. 4) of the substantially flat plate-shaped portion that overlaps the resin member 12 in the metal member 11 is usually 0.5 to 4 mm, but is not limited thereto.

As the metal constituting the metal member 11, any metal having a melting point higher than that of the thermoplastic polymer constituting the resin member 12 can be used. Among these, the following metals and alloys used in the automotive field are preferably used:
aluminum;
Aluminum alloys such as 5000 series and 6000 series;
steel;
Magnesium and its alloys;
Titanium and its alloys.

  Preferred metals constituting the metal member 11 are aluminum and an aluminum alloy.

(4) Resin member The resin member 12 used in the present invention contains a thermoplastic polymer and reinforcing fibers.

As the thermoplastic polymer constituting the resin member 12, any polymer having thermoplasticity can be used. Of these, thermoplastic polymers used in the field of automobiles are preferably used. Specific examples of such thermoplastic polymers include, for example, the following polymers and mixtures thereof:
Polyolefin resins such as polyethylene and polypropylene and acid-modified products thereof;
Polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polylactic acid (PLA);
Polyacrylate resins such as polymethyl methacrylate resin (PMMA);
Polyether resins such as polyether ether ketone (PEEK) and polyphenylene ether (PPE);
Polyacetal (POM);
Acrylonitrile-butadiene-styrene copolymer resin (ABS);
Polyphenylene sulfide (PPS);
PA6, PA66, PA11, PA12, PA6T, PA9T, MXD6 and other polyamide-based resins (PA);
Polycarbonate resin (PC);
Polyurethane resin;
A fluoropolymer resin; and a liquid crystal polymer (LCP).

  As the thermoplastic polymer constituting the resin member 12, a polyolefin resin, particularly polypropylene, which is inexpensive and excellent in mechanical properties is preferably used.

  The molecular weight of the thermoplastic polymer is not particularly limited. For example, the molecular weight may be such that the MFR (melt flow rate value) at 230 ° C. is 2 to 200 g / 10 minutes, particularly 2 to 55 g / 10 minutes. .

  In this specification, the value measured by JIS K 7210 is used for the MFR of the polymer.

  The resin member 12 has a substantially flat plate shape as an overall shape in FIG. 1 and the like, but is not limited to this. When the resin member 12 is overlapped with the metal member 11 for bonding, the resin member 12 is directly below the metal member 11. As long as the portion has a substantially flat plate shape, it may have any shape. The part immediately below the metal member 11 in the resin member 12 is generally composed of a flat surface on both sides.

  The thickness t (thickness before joining treatment; see FIG. 4) of the portion immediately below the metal member 11 in the resin member 12 is usually 2 to 10 mm, particularly 2 to 5 mm, but is not limited thereto.

  In the field of polymer-containing composite materials, the reinforcing fibers contained in the resin member 12 are fibers that are uniformly contained and dispersed in the polymer in order to improve strength, and are generally large in continuous fibers and discontinuous fibers. Although different, the reinforcing fiber in the present invention shall mean a discontinuous fiber. This is because discontinuous fibers are considered to be prone to spring back, and in the present invention, even when such discontinuous fibers are contained, spring back can be sufficiently prevented.

  The reinforcing fibers are contained in the resin member in a randomly oriented form, and the average fiber length L is usually 50 mm or less, particularly more than 1 mm and 50 mm or less, preferably more than 1 mm and 30 mm or less. The average fiber diameter of the reinforcing fibers is not particularly limited, and is, for example, 2 to 20 μm, preferably 6 to 15 μm. The type of reinforcing fiber is not particularly limited, and examples thereof include carbon fiber and glass fiber.

  The content of the reinforcing fiber is usually 1% by weight or more, particularly 10 to 50% by weight, preferably 20 to 50% by weight, more preferably 30 to 50% by weight, based on the total amount of the resin member.

  As the content of the reinforcing fiber, a value based on the amount of each material used at the time of manufacturing the resin member can be used, and a value measured by the following method can also be used. First, a resin member or a part (sample) thereof is heated by an electric furnace or the like at a temperature not lower than the decomposition temperature of the thermoplastic polymer (resin component) and not higher than the decomposition temperature of the reinforcing fiber, thereby removing the thermoplastic polymer and reinforcing fiber. Take out only. At this time, only the reinforcing fiber can be taken out by dissolving the resin member or a part (sample) thereof in a solvent in which the thermoplastic polymer can be dissolved and filtering the reinforcing fiber. By measuring the weight before and after heating or before and after dissolution, the content of reinforcing fibers can be calculated as a ratio to the weight of the sample. Alternatively, the content can be measured by measuring the specific gravity.

  The resin member 12 may further contain additives other than reinforcing fibers, such as stabilizers, flame retardants, colorants, foaming agents, and the like.

  The resin member 12 can be manufactured by subjecting a mixture containing a thermoplastic polymer and reinforcing fibers and a desired additive to a molding method such as an injection molding method or a press molding method.

The melting point Tm of the resin member 12 varies depending on the type of the resin member 12, and is usually 130 to 350 ° C.
As the melting point Tm of the resin member 12, a value measured according to JIS 7121 is used.

(5) Bonded Body The bonded body of the metal member 11 and the resin member 12 bonded by the bonding method of the present invention is achieved in the melt-solidified region 61 of the resin member 12.

  As shown in FIG. 6, the melted and solidified region 61 (hatched region) is a region formed by melting and solidifying the resin member 12 at the time of joining, and melting on the metal member side surface 121 of the resin member 12 occurs. This is a region where there is a step that can be distinguished on the outer periphery of the region 122 that is not. As shown in FIG. 6, the melt-solidified region 61 is usually formed in the region 60 directly below the rotary tool on the metal member side surface 121 of the resin member 12 and the outer peripheral region thereof. FIG. 6 is a schematic diagram showing the surface state of the resin member 12 when the metal member is forcibly separated from the joined body obtained by the joining method of the present invention and the metal member side surface 121 of the resin member 12 is observed. It is.

  In the joined body of the present invention, when the diameter of the melt-solidified region 61 is R (mm) and the diameter of the rotary tool is D1 (mm), R / D1 is usually 1 to 5, preferably 2 to 5. Yes, more preferably 3-5.

  In the present invention, the bubble layer forming region 62 (lattice region) is formed with a thickness of 1 mm or less, that is, 0 (not including 0) to 1 (including 1) mm on the surface of the melt-solidified region 61 on the metal member side. The In the present invention, when a special resin member and / or special cooling for preventing the formation of the bubble layer is not used, when the heat input is reduced to a condition where the bubble layer is not formed, the melt-solidified region becomes too small, In some cases, sufficient bonding strength cannot be obtained. Even if a bubble layer having a thickness of more than 1 mm is formed, sufficient bonding strength cannot be obtained. The thickness of the bubble layer 62 is preferably 0.9 mm or less, more preferably 0.5 mm or less, from the viewpoint of further improving the bonding strength. In the present specification, unless otherwise specified, the numerical range includes a value as a lower limit value or an upper limit value thereof.

  The presence of the bubble layer formation region 62 can be easily confirmed by visual inspection in FIG. 6 due to the presence of bubbles.

The thickness of the bubble layer forming region 62 can be measured by the following method.
With the metal member 11 and the resin member 12 being joined as shown in FIG. 7, the thickness is measured by observing a cross section in the plate thickness direction of a portion to be measured (that is, in the vicinity of the portion immediately below the rotary tool). Since the bubble layer 20 is in a state where air is taken in and foamed, a difference from other parts can be easily confirmed visually. FIG. 7 is an enlarged view of a joint interface between a metal member and a resin member in a joined body obtained by the joining method of the present invention.
Specifically, the maximum thickness of the bubble layer is determined in the region immediately below the rotary tool and in the periphery (melt-solidified region) in the cross-sectional image of the joined body.

  As described above, in the present invention, the case where the metal member and the resin member are joined in a spot shape without moving the rotating tool in the surface direction on the contact surface of the metal member (point joining) has been described. It is clear that the effect of the present invention can be obtained even when the metal member and the resin member are joined linearly (line joining) while moving the rotary tool in the direction.

[Resin member]
A resin member 12 having dimensions of 100 mm in length, 30 mm in width, and 3 mm in thickness was produced by an injection molding method using polypropylene pellets containing 40% by weight of carbon fibers (PP-CF40-11; manufactured by Daicel Polymer Co., Ltd.). In the resin member, the average fiber length of the carbon fibers was 3 mm, and the average fiber diameter was 7 μm. The melting point Tm of the resin member was 170 ° C. In the resin member, the carbon fibers were randomly oriented.

[Metal members]
As the metal member, a flat plate member (length 100 mm × width 30 mm × thickness 1.2 mm) made of a 6000 series aluminum alloy was used.

[Rotation tool]
The rotary tool 16 shown in FIG. 2 (D1 = 10 mm, D2 = 2 mm, h = 0.5 mm, θ = 0 °; made of tool steel) or the rotary tool 16 ′ shown in FIG. 3 (D1 = 10 mm, D2 = 2 mm, h = 0.5 mm, θ = 7 °; made of tool steel).

[Example A1] (pressure control method)
The joined body of the metal member 11 and the resin member 12 was manufactured by the following method.
First step:
The end of the metal member 11 and the end of the resin member 12 were overlapped as shown in FIG.

Second step:
First, as shown in FIG. 4, the rotary tool 16 was rotated in a state where only the tip portion of the rotary tool 16 was in contact with the surface portion of the metal member 11 (preheating step C1: pressure 900N, pressurization time 1. 00 seconds, tool rotation speed 3000 rpm).

Thereafter, as shown in FIG. 5, the rotary tool 16 was pushed into the metal member 11 to a depth not reaching the joint boundary surface 13 between the metal member 11 and the resin member 12 (pushing stirring step C2: pressure 1500N. , Pressurization time 0.25 seconds, tool rotation speed 3000 rpm).
Next, as shown in FIG. 5, the rotation operation of the rotary tool 16 was continued at a position where the rotary tool 16 was advanced to a depth that did not reach the joining boundary surface 13 (stirring maintenance step C3: pressurizing force 500 N, pressurization) Time 2.75 seconds, tool rotation speed 3000 rpm).
Next, the rotary tool 16 was separated from the metal member 11 and allowed to cool down to obtain a joined body.

[Joint strength]
As shown in FIG. 8, the joined body of the metal member 11 and the resin member 12 was placed in the jig 100. The jig 100 is configured such that a downward force acts on the upper end portion of the resin member 12 by pulling the jig 100 downward. By fixing the jig 100 and pulling the metal member 11 upward, a downward force acts on the upper end portion of the resin member 12, and the shear strength of the joint portion is not affected by the strength of the base material of the resin member 12. S was measured.
A: 4.0 ≦ S;
○; 3.0 ≦ S <4.0;
X: S <3.0 (practical problem).

[Melting area]
The diameter R of the melt-solidified region 61 was measured based on the step on the outer periphery. The diameter R is the maximum diameter of the melt-solidified region 61.

[Bubble layer]
The thickness of the bubble layer (so-called springback layer) was measured by the method described above.

[Examples A2 to A4 and Comparative Examples A1 to A3]
Except that the joining conditions were changed as shown in Table 1, the resin member and the metal member were joined and the joined body was evaluated by the same method as in Example A1.

[Example B1] (Position control method)
The joined body of the metal member 11 and the resin member 12 was manufactured by the following method.
First step:
The end of the metal member 11 and the end of the resin member 12 were overlapped as shown in FIG.

Second step:
First, without performing the preheating step C1, as shown in FIG. 5, the rotary tool 16 is pushed into the metal member 11 to a depth that does not reach the joint boundary surface 13 between the metal member 11 and the resin member 12 ( Indentation stirring step C2: ingress amount 0.8 mm, ingress speed 0.2 mm / sec, tool rotation speed 3000 rpm).
Next, as shown in FIG. 5, the rotation operation of the rotary tool 16 was continued at a position where the rotary tool 16 was advanced to a depth that did not reach the joining boundary surface 13 (stirring maintenance step C3: holding time 3.00 seconds). Tool rotation speed 3000 rpm).
Next, the rotary tool 16 was separated from the metal member 11 and allowed to cool down to obtain a joined body.

  Thereafter, the joined body was evaluated by the same method as in Example A1.

[Examples B2 to B6 and Comparative Examples B1 to B4]
Except that the joining conditions were changed as shown in Table 1, the resin member and the metal member were joined and the joined body was evaluated by the same method as in Example A1.

  The joining method according to the present invention is useful for joining a metal member and a resin member in the fields of automobiles, railway vehicles, aircraft, home appliances, and the like.

1: Friction stir welding apparatus 10: Work 11: Metal member 12: Resin member 13: Joining interface between metal member and resin member 16: Rotating tool 17: Receiving tool 20: Bubble layer 100: For measuring joint strength Jig 110: Immediately below the rotating tool of the metal member P: Pressing area (planned pressing area)
121: Surface layer portion of region directly under rotating tool in resin member

Claims (18)

The metal member and the resin member containing the reinforcing fiber are superposed, pressure is applied to the resin member by pressing from the metal member side by the pressing member, heat is applied to soften and melt the resin member, and then solidify It is a joining method of a metal member and a resin member by a hot-pressure joining method that performs joining,
The hot-pressure bonding method is
A first step of superimposing the metal member and the resin member; and
A second tool that presses against a metal member to generate frictional heat while rotating the rotary tool as a pressing member, softens and melts the resin member with the frictional heat, and then solidifies the second member to join the metal member and the resin member. A friction stir welding method including steps,
Joining by controlling the driving of the rotary tool so that a bubble layer is formed with a thickness of 0 (not including 0) to 1 (including 1) mm on the surface of the melted and solidified region of the resin member on the metal member side A method for joining the metal member and the resin member.   The metal member and the resin member according to claim 1, wherein driving of the pressing member and application of heat are controlled so that a bubble layer is formed with the thickness on the surface of the molten and solidified region of the resin member. Joining method. The joining method of the metal member and resin member of Claim 1 or 2 which controls the pressing drive and / or rotational drive of a rotary tool. Adopting a pressure control method in the second step,
The joining method of the metal member and resin member in any one of Claims 1-3 which controls the pressurizing force and pressurization time to a metal member of a rotary tool, and rotation speed. The second step includes
A preheating step of rotating the rotary tool in a state where only the tip of the rotary tool is in contact with the surface of the metal member;
A pushing agitation step of pushing the rotating tool into the metal member and entering the metal member and the resin member to a depth not reaching the joining boundary surface; and a position where the rotating tool is entered in the pushing agitation step. Including an agitation maintaining step for continuing the rotation operation,
In the preheating step, the rotary tool is rotated by the first pressurizing time while being pressed with the first pressurizing force,
In the indentation stirring step, the rotary tool is rotated by a second pressurization time shorter than the first pressurization time while pressing the rotary tool with a second pressurization force larger than the first pressurization force,
The agitation in the sustain step rotates only between long third pressurization than between the first pressurization while pressing the rotating tool in the first pressure is less than the third pressure, according to claim 4 A method of joining a metal member and a resin member. In the preheating step, the first pressurizing force is adjusted in a range of 600 N or more and less than 1300 N, and the first pressurizing time is adjusted in a range of 0.5 second or more and less than 2.0 seconds,
In the indentation stirring step, the second pressure is adjusted in the range of 1300 N or more and less than 2200 N, the second pressurizing time is adjusted in the range of 0.1 second or more and less than 0.5 second,
In the stirring step of maintaining the third pressure adjusted in a range of less than or more 100 N 1200 N, is adjusted in the third range pressing time of less than 2.0 seconds to 8.5 seconds, according to claim 5 Joining method of metal member and resin member. The joining of the metal member and the resin member according to claim 6 , wherein in the preheating step, the indentation stirring step, and the stirring maintaining step, the number of rotations of the rotary tool is independently adjusted in a range of 2000 rpm to 4000 rpm. Method. Adopting a position control method in the second step,
Coordinate position of the rotary tool, to control the retention time and the rotational speed at a specific location, method of joining the metal member and the resin member according to any one of claims 1 to 7. The second step includes
Including a pushing agitation step of pushing the rotating tool into the metal member to enter a depth that does not reach the joining interface between the metal member and the resin member;
9. The metal member according to claim 8 , wherein in the indentation stirring step, the rotating tool is caused to enter the metal member up to an amount of entry of 0.4 × T to 0.9 × T, where T is the thickness of the metal member. And joining method of resin member. The second step further includes
A stirring maintaining step of continuing the rotating operation of the rotating tool at a position where the rotating tool is entered in the indentation stirring step;
Including
In the stirring maintaining step, the rotating tool is held at a position where the rotating tool is entered in the indenting stirring step for not less than 2.0 seconds and less than 8.5 seconds,
The joining method of the metal member and resin member of Claim 9 which makes a rotary tool approach at the approach speed of 0.05-1 mm / sec in the said pushing stirring process. The joining method of the metal member and resin member of Claim 9 or 10 which adjusts the rotation speed of a rotary tool in the range of 2000 rpm or more and 4000 rpm or less each independently in the said pushing stirring process and the said stirring maintenance process. The thickness T of the metal member is 0.5 to 4 mm, method of joining the metal member and the resin member according to any one of claims 1 to 11. The metal member is made of aluminum or an aluminum alloy,
The resin member has a melting point Tm of the one hundred and thirty to three hundred and fifty ° C., method of joining the metal member and the resin member according to any one of claims 1 to 12. The rotating tool has a pin portion projecting on a central axis of the rotating tool and a shoulder portion supporting the pin portion at a tip portion in contact with the metal member, and the shoulder portion is recessed in a mortar shape. It has an inclined surface, method of joining the metal member and the resin member according to any one of claims 1 to 13. The average fiber length L of the reinforcing fiber is 1mm super 50mm or less, method of joining the metal member and the resin member according to any of claims 1-14. The joining method of the metal member and resin member in any one of Claims 1-15 in which the said resin member contains the said reinforcement fiber in the ratio of 10 to 50 weight% with respect to this resin member whole quantity. The metal member and resin member according to any one of claims 1 to 16 , wherein the resin member is produced by subjecting a mixture containing a thermoplastic polymer and reinforcing fibers to an injection molding method or a press molding method. Joining method. The method for joining a metal member and a resin member according to any one of claims 1 to 17 , wherein the solidification is performed by standing cooling.

Images