JP2002066766A - Joining method for members - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress lowering in joint strength which is caused by heat. SOLUTION: A non-heat-treated aluminum alloy steel plate which has a small calorific value compared with the second joining member W2 is arranged as a member on a side where a rotation direction R of a rotary tool 1 goes in a traveling direction V to the traveling direction V of the rotary tool 1 of the first joining member W1, and a heat-treated aluminum alloy steel plate which has a large calorific value cam-pared with the first joining member W1 is arranged as a member on a side where the rotation direction R of the rotary tool 1 goes opposite to the traveling direction V to the traveling direction V of the rotary tool 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining members such as aluminum alloy plates and press-formed bodies.

[0002]

2. Description of the Related Art In the conventional joining technique, a plate material or a material previously press-formed into a three-dimensional shape is abutted and joined by electric resistance welding, arc welding, an adhesive or the like.

[0003] As another joining technique, a joining method of friction stirring in a non-molten state is disclosed in Japanese Patent No. 2712838. In this joining technique, a projecting portion 2 projecting from a planar shoulder 3 called a probe of a rotary tool 1 shown in FIG. Tissue is plasticized by frictional heat and bonded.

[0004]

In the joining technique described in the above publication, the joining is performed as follows. That is, i) the rotating probe 2 advances while forming a groove in the abutting surface of the joining members W1 and W2.

Ii) The abutting surfaces of the joining members W1 and W2 are softened by frictional heat between the shoulder 3 and the joining members W1 and W2.

Iii) The metal structure of the softened butted surface plastically flows due to the stirring of the shoulder 3 and the probe 2, and is filled in the groove formed by the probe 2.

[0007] By repeating the above steps i) to iii), the butted surfaces of the joining members W1 and W2 are joined.

[0010] However, as shown in FIGS. 4 and 5, the rotational direction R of the rotary tool 1 in the advancing direction V with respect to the advancing direction V of the rotary tool 1 in the butted joining members W 1 and W 2. In the metallographic structure of the member W1, the relative movement of the shoulder 3 with respect to the rotation direction R increases, and the amount of generated heat increases, and conversely, the rotation direction R of the rotary tool 1 changes with respect to the travel direction V of the rotary tool 1. In the metal structure of the member W2 on the side opposite to the above, since the relative movement of the shoulder 3 in the rotation direction R is small, the calorific value is small. As a result, a temperature difference of about 10 ° C. is generated between the joining members W1 and W2, causing a reduction in agitation and joining strength.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for joining members which can suppress a decrease in joining strength due to the influence of heat.

[0010]

In order to solve the above-mentioned problems and achieve the object, a method of joining members according to the present invention comprises:
In the joining method of a member in which a member and a second member are abutted and a rotating member is rotated and advanced along the abutted joint surface to stir by friction in a non-molten state and join the first member, And the second member suppresses the amount of heat generated by the member on the side where the rotating direction of the rotating member is directed toward the advancing direction with respect to the advancing direction of the rotating member.

Preferably, of the first member and the second member, a member on a side where the rotation direction of the rotating member is in the traveling direction with respect to the traveling direction of the rotating member is cooled.

In the method of joining members according to the present invention, a first member and a second member of different types are brought into contact with each other, and the rotating member is advanced while rotating along the joined surface where the first member and the second member are joined. In the joining method of members to be stirred and joined together, a member having a high melting point of the first member and the second member is placed on a side where the rotating direction of the rotating member is in the traveling direction with respect to the traveling direction of the rotating member. To place.

In the method for joining members according to the present invention, a heat-treated steel sheet and a non-heat-treated steel sheet are butted, and a rotating member is rotated and advanced along the joined face to agitate by friction in a non-molten state. In the method for joining members to be joined by joining, the non-heat-treated steel sheet is arranged on a side where the rotation direction of the rotating member is directed toward the traveling direction with respect to the traveling direction of the rotating member.

[0014]

As described above, according to the first aspect of the present invention, of the first member and the second member, the rotation direction of the rotating member with respect to the traveling direction of the rotating member is the side facing the traveling direction. By suppressing the calorific value of the member, it is possible to suppress a decrease in bonding strength due to the influence of heat.

According to the second aspect of the present invention, the first member and the second member
By cooling the member on the side where the rotating direction of the rotating member is in the direction of travel with respect to the traveling direction of the rotating member, the amount of generated heat can be suppressed by a simple method.

According to the third aspect of the present invention, the first member and the second member
By arranging the member having a high melting point among the members on the side where the rotating direction of the rotating member is directed toward the advancing direction with respect to the advancing direction of the rotating member, it is possible to suppress a decrease in bonding strength due to the influence of heat only by arranging the members. This is suitable when it is desired to change the strength for each joint portion.

According to the fourth aspect of the present invention, since the non-heat-treated steel sheet is arranged on the side where the rotating direction of the rotating member is directed toward the advancing direction with respect to the advancing direction of the rotating member, the influence of heat is affected only by the arrangement of the members. Therefore, it is possible to suppress a decrease in bonding strength due to the above, and it is suitable when it is desired to change the strength for each bonding portion.

[0018]

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

The embodiment described below is an example as a means for realizing the present invention, and the present invention can be applied to a modification or modification of the following embodiment without departing from the gist thereof. .

FIG. 1 is an enlarged view of the vicinity of a rotary tool for explaining a joining method according to an embodiment of the present invention. FIG. 2 shows FIG.
It is sectional drawing of the member structure | tissue of the joining part of.

The joining method according to the present embodiment is applied to joining of a plate material made of an aluminum alloy and a material which has been previously press-formed into a three-dimensional shape. By pushing the probe 2 of the rotary tool 1 shown in FIG. 1 while pushing it, the member structure of the butted surfaces of the first and second joining members W1 and W2 is agitated and joined in a non-melting manner by frictional heat.

Since the stirring is performed in a non-melting state, problems such as thermal distortion generated by electric resistance welding or the like can be solved.

Here, the non-melting and stirring state means that the member structure is softened by frictional heat at a temperature lower than the lowest melting point among the components or eutectic compounds contained in the base material. Means to stir.

As shown in FIG. 1, in the joining method by friction stirring, a cylindrical rotary tool 1 having at least two joining members W1 and W2 butted together and having a projection 3 on a shoulder 3 is provided.
At the same time that the protrusion 2 is cut into the abutting surfaces of the joining members W1 and W2 while rotating about the axis thereof.
The lower end surface of the shoulder 3 presses the upper surfaces of the joining members W1 and W2 orthogonal to the abutting surface, and the abutted first and second joining members W1 and W2 are agitated by friction in a non-molten state, and the materials are joined together. To join.

A receiving member 4 is arranged so as to face the shoulder 3 of the rotary tool 1 so as to sandwich the butted surfaces of the first and second joining members W1 and W2. The outer diameter of the receiving member 4 is designed to be larger than the outer diameter of the rotary tool 1.

As shown in FIG. 2, the rotary tool 1 has a diameter of φ1.
Is about 10 to 15 mm, and the diameter 2 of the protrusion 2 is 5 to 7 mm.
The diameter φ3 of the joint portion is about 8 to 9 mm.

The rotary tool 1 and the receiving member 4 are non-wear type tools made of a steel material (such as a cemented carbide) having a higher hardness than the joining member, but the joining material may be softer than the rotating tool 1. The invention is not limited to aluminum alloys.

The length X1 of the protruding portion is equal to the depth X2 of the joining portion.
And the junction portion depth X2 is 1.1 to 1.2 times the protruding portion length X1. Junction depth X2
Is proportional to the length X1 of the protrusion (1.1 to 1.2 of the pin length).
Times) and increase.

The rotary tool 1 is an articulated robot 1 described later.
It is rotatably attached to the 0 arm or the machining center, and is configured to be able to join even if the material has a complicated three-dimensional shape.

FIG. 3 is a schematic diagram of an articulated robot that holds and drives a rotary tool.

As shown in FIG. 3, the articulated robot 10
Is connected to a joint 12 provided on a base 11 and swings about a y-axis, and is rotated by a joint 13 about a z-axis. The first arm 14 is connected to a first arm 14 via a joint 15. A second arm 17 swinging about the y-axis and rotating about the x-axis at a joint 16, and a third arm 19 connected to the second arm 17 via a joint 18 and swinging about the y-axis. Having.

The third arm 19 includes a motor 20 to which the rotary tool 1 is rotatably mounted, a motor 20 for driving the rotary tool 1 to rotate, and a receiving member 4 arranged to face the shoulder 3 of the rotary tool 1. . The distance between the shoulder 3 of the rotary tool 1 and the shoulder of the receiving member 4 is
2, the pressing force against the material at the time of joining can be adjusted.

Each arm, motor,
The operation of the actuator is previously taught and controlled by the control unit 30.

The pressing force of the rotary tool 1 on the joining member is
It is set based on the thickness of the material.

In this embodiment, as the first joining member W1, 1000 series, 3000 series, 5000 series based on the JIS standard.
Non-heat treatment type aluminum alloy steel sheet, such as 2000 series, 4000 series, 6000 series, 70
A heat treatment type aluminum alloy steel sheet such as 00 series or AC4C is applied. Then, a non-heat-treated aluminum alloy steel sheet having a smaller calorific value than the second joining member W2 is used as a member in which the rotation direction R of the rotary tool 1 is on the side of the progress direction V with respect to the travel direction V of the rotary tool 1. Place and rotate tool 1
The first joining member W is a member in which the rotational direction R of the rotary tool 1 is on the side opposite to the traveling direction V with respect to the traveling direction V of
A heat-treatable aluminum alloy steel sheet having a larger calorific value than that of No. 1 is arranged.

By arranging and joining in this way,
Of the first and second joining members W1 and W2, the heat generation of the member W1 on the side where the rotation direction R of the rotary tool 1 is in the direction of travel V with respect to the direction of travel V of the rotary tool 1 is suppressed, resulting from the temperature difference. This can suppress the lowering of the agitation property and the joining strength.

In order to suppress the heat generation, the rotary tool 1
It is also possible to cool the first joining member on the side where the rotating direction R of the rotary tool 1 is directed toward the traveling direction V with respect to the traveling direction V of
In this case, the same type of aluminum alloy or a casting and an aluminum alloy can be applied.

Also, the present invention can be applied to the joining of plastic materials having different melting points. In this case, the member having the higher melting point among the first joining member and the second joining member is connected to the traveling direction V of the rotary tool 1.
, The rotation direction R of the rotary tool 1 is disposed on the side facing the traveling direction V.

The rotational speed of the rotary tool 1 whose joining strength satisfies the required strength is preferably 1000 to 2500 rpm. If the rotating speed is lower than 1000 rpm, the stirring is insufficient due to insufficient agitation, and if the rotating speed is higher than 2500 rpm. Since the member structure to be agitated does not rotate and is not agitated, the joining strength is reduced. [Applied Material] The joining method of the present embodiment can be applied to press molding in which a large number of parts are joined and then pressed to form a single part. In the joining inside a side frame, a door or a lift gate of an automobile, For example, it is suitable for changing the strength for each part of the side frame.

[Brief description of the drawings]

FIG. 1 is an enlarged view near a rotary tool for explaining a joining method according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a member structure of a joining portion in FIG.

FIG. 3 is a schematic diagram of an articulated robot that holds and drives a rotary tool.

FIG. 4 is a diagram illustrating a method of joining members according to the present embodiment.

FIG. 5 is a cross-sectional view showing a flow state of a member tissue at a joining portion immediately after passing through a probe.

FIG. 6 is a perspective view of a rotary tool used in the joining method according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary tool 2 Projection part 3 Shoulder 4 Receiving member 10 Articulated robot W1, W2 Joining member

Claims (4)

[Claims] 1. A first member and a second member are abutted against each other,
In the joining method of joining members by stirring and agitating by friction in a non-molten state by rotating and advancing a rotating member along the joined joining surface, the rotating member among the first member and the second member A method of joining members, wherein the amount of heat generated by a member whose rotational direction is directed toward the traveling direction with respect to the traveling direction of the member is suppressed. 2. The cooling device according to claim 1, wherein, of the first member and the second member, a member on a side where the rotating direction of the rotating member is in the advancing direction with respect to the advancing direction of the rotating member is cooled. The method for joining members according to claim 1. 3. A member to join a first member and a second member of different types by agitating by friction in a non-molten state by advancing while rotating a rotating member along the abutted joint surface. In the joining method, the member having a higher melting point among the first member and the second member is disposed on a side where the rotating direction of the rotating member is directed toward the traveling direction with respect to the traveling direction of the rotating member. The method of joining members. 4. A method for joining members to be joined by bringing a heat-treated steel sheet and a non-heat-treated steel sheet into contact with each other and rotating and rotating a rotating member along the joined joining surface to stir by friction in a non-molten state. The method for joining members, wherein the non-heat-treated steel sheet is disposed on a side where a rotation direction of the rotating member is directed to the traveling direction with respect to a traveling direction of the rotating member.