JPH03184682A - Friction joining method - Google Patents

Abstract

PURPOSE:To carry out firm joining by the low frictional force by maintaining the inside of an airtight chamber surrounding the vicinity of the joining face in an inert atmospher and giving the frictional force to the joining face to carry out joining. CONSTITUTION:The frictional force is given to the joining face between materials 3 and 5 to be joined to carry out friction joining. The vicinity of the joining face between the materials 3 and 5 to be joined is then surrounded airtightly by the airtight chamber 10. The inside of the airtight chamber 10 is maintained in the inert atmospher containing a vacuum or inert gas or <=100ppm oxygen. In that state, the frictional force is given to the joining face to carry out joining. The joining face of the materials to be joined is activated by the physical activation method and then, the frictional force is given to the joining face. By this method, plastic deformation and deterioration of the materials can be prevented.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a friction welding method.

[Prior Art] The friction welding method is a method in which materials to be joined are brought into contact with each other and subjected to relative rotational motion, and the materials are joined by utilizing the frictional heat generated at the joining surfaces.

FIG. 6 shows an example of a device for carrying out the conventional friction welding method, which includes a rotary chuck 4 attached to a flywheel 2 rotated by an electric motor 1, which clamps and rotates one of the welding materials 3, and the rotary chuck 4. a fixed chuck that is disposed on the same axis as the rotary chuck 4, clamps the other joining material 5 facing the joining material 3, and is provided so as to be movable toward and away from the rotary chuck 4 along a guide member 6; 7, and a suppression device 8 consisting of a hydraulic cylinder or the like that moves the fixed chuck 7 and presses the bonding material 3.5.

While the rotary chuck 4 to which one of the joining materials 3 is attached is rotated at a constant rotation speed, the stationary chuck 7 to which the other joining material 5 is attached is advanced by the pressing device 8, thereby joining the joining materials 3.5. When the surfaces are pressed against each other, the friction portion becomes red hot and softens, and the rotational energy is consumed by heat generation, so that the rotational motion rapidly decelerates and comes to a natural stop, completing the pressing. In the above, a method is also adopted in which the brake is applied to stop the rotation when the friction part reaches an appropriate temperature.

In pressing after the rotation is stopped, the pressure is generally maintained as an upset pressure, or is further increased to perform an upset.

During the above-mentioned friction welding, there are oxides, thin gas adsorption films, dirt, etc. on the welding surfaces that interfere with the welding, so these are decomposed during the friction or caused by large pressure to form burrs 9 at the welded part as shown in Figure 7. High bonding strength is obtained by extruding the material to the outside and activating it, and the temperature of the friction part in conventional methods usually rises to just below the melting point of the material.

[Problems to be Solved by the Invention] However, in the above conventional method, in order to activate the joint surfaces and obtain a strong joint, sufficient burrs 9 are formed at the joint part using a strong pressing force. As a result, the plastic deformation of the bonding material 3.5 is significant, and there is a problem in that it requires a robust device and a large driving force.

Furthermore, even if the joint surface is activated by a strong pressing force as described above, the red-hot friction part will immediately oxidize, resulting in oxides being mixed into the friction part. This causes problems such as deterioration of the quality of the joint and a decrease in strength, which narrows the range of materials that can be joined.

The present invention was made by focusing on the above-mentioned conventional problems.
It is an object of the present invention to provide a friction welding method that enables high-strength welding with a simple configuration and can expand the types of materials that can be joined.

[Means for Solving the Problems] The present invention relates to a friction welding method in which opposing joint surfaces of joining materials are joined by applying a frictional force, the vicinity of the joining surfaces of the joining materials being hermetically surrounded by an airtight chamber, The inside of the airtight chamber is vacuumed, or an inert gas or loppm is applied.
A friction welding method characterized in that the welding is performed by applying a frictional force to the joining surfaces in a state maintained in an inert atmosphere containing oxygen as described below, or on the opposing joining surfaces of the joining materials,
In the friction welding method, which involves applying frictional force to join, the vicinity of the joining surfaces of the joining materials is hermetically surrounded by an airtight chamber, and the inside of the airtight chamber is filled with a vacuum, an inert gas, or an inert gas containing 1 Opps or less of oxygen. The friction welding method is characterized in that the bonding surfaces of the bonding materials are activated by a physical activation method in a state maintained in an atmosphere, and then the bonding is performed by applying frictional force to the bonding surfaces. .

[Function] Friction welding is performed using vacuum, inert gas or 1 opp■
When bonding is carried out in an inert atmosphere containing oxygen as described below, the bonding surfaces are favorably activated and strong bonding is possible with small frictional force. By making it possible to join with the above-mentioned small frictional force, plastic deformation and deterioration of the joining material can be prevented, and the structure of the device for applying the frictional force can also be made smaller and lighter.

Furthermore, since the airtight chamber locally surrounds only the vicinity of the bonding surfaces of the bonding materials, the time required to maintain the interior in a vacuum or inert atmosphere can be reduced, and the device can be made more compact. I can figure it out.

Furthermore, if the bonding surfaces are activated by a physical activation method prior to bonding, even more reliable bonding can be achieved.

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

FIG. 1 shows an example of an apparatus for carrying out the method of the present invention, and the parts in the figure with the same reference numerals as in FIG. 6 represent the same parts.

As shown in FIG. 1, an airtight chamber is configured to locally and airtightly surround the opposing joint surfaces of one joining material 3 attached to the rotating chuck 4 and the other joining material 5 attached to the stationary chuck 7. 1O is provided on a support stand 11, and a vacuum generator 13 is connected to the airtight chamber 10 via a suction pipe 12.

FIG. 2 shows an example of the airtight chamber lO,
The airtight chamber IO has a flange portion 1 provided at the open end.
Two boxes 15 with a two-sided structure that can be assembled in 4
．． 1B, and the bottom part 1 of the box body 15.1G.
Insertion ports 17.18 are formed on the same axis at 5° and 16°, and a local seal device 19 is attached to the insertion ports 17.18.

As shown in FIG. 3 using the box body 15 as an example, the local sealing device 19 is configured to form an annular concave space 20 that is open on the inside in the radial direction on the outside of the bottom portion 15' in which the insertion port 17 is formed. A support fitting 21 is fixed via a seal ring 22, and an annular seal body 23 is inserted into the concave space 20.

The seal body 23 includes an inner seal plate 24 and an outer seal plate 25.
The sealing material 26 is made of a synthetic resin material having the required elastic deformability and high abrasion resistance. There is.

An annular coil spring 27 having a high elasticity is inserted into the C-shaped interior of the sealing material 2B.

In the above configuration, the inner diameter of the seal body 23 is slightly smaller than the outer diameter of the bonding material 3 etc. that performs sealing, so when the bonding material 3 is pushed inside the seal body 23, the inner seal plate 24 is expanded, and the coil spring 27 becomes a crushed shape as shown in FIG. This ensures high sealing performance.

Further, a viewing window 28 is provided on the side surface of the box 15 in the airtight chamber 1O, through which the alignment and bonding state of the bonding materials 3 and 5 can be monitored from outside the airtight chamber 10.

The bonding material 3.5 is inserted into each of the insertion ports 17.18 equipped with the local sealing device 19 of the above-mentioned airtight chamber IO, and each of the bonding materials 3.5 is aligned with the rotary chuck 4 and the fixed chuck 7. After the airtight chamber 1O is installed in this state, it is supported on a support base 11 so that the airtight chamber 1O does not rotate.

Subsequently, suction is performed by the vacuum generator 13 to maintain the inside of the airtight chamber IO in a vacuum.

In this state, the electric motor 1 is driven to rotate the rotating chuck 4 and one of the joining materials 3 via the flywheel 2, and the fixed chuck 7 is further advanced by the pressing device 8 so that the joining surface of the other joining material 5 is pushed to one side. Press it against the joining surface of the joining material 3.

Then, the bonding surfaces are immediately activated by friction due to the vacuum atmosphere, and therefore, they are firmly bonded with a small pressing force and at a low friction temperature.

Therefore, the plastic deformation of the joint is extremely small, and a strong joint can be achieved with almost no deterioration of the joint.

The joining material 3.5 that has been joined as described above can be removed from the chuck 4.7 and pulled out from the airtight chamber 10. However, if it cannot be pulled out due to slight deformation of the joint, etc., the flange At section 14, the airtight chamber IO can be divided into two parts and taken out.

In addition, prior to the bonding, the bonding surface of the bonding material 3.5 is
By actively activating the material by a physical activation method in a vacuum atmosphere, even stronger bonding can be easily and stably obtained.

FIG. 4 shows an example of the above-mentioned physical activation method, in which a processing tool storage chamber 29 is provided projecting from the side opposite to the observation window 28 in the airtight chamber IO, and is provided inside the airtight chamber IO. An operating arm 31 fixed to a processing tool 30 made of a polished file, diamond polishing, etc.
An arm insertion opening 32 formed on the outside wall of the processing tool storage chamber 29 and equipped with a local sealing device 19 similar to that described above is inserted through the arm insertion opening 32 .

In this case, cutting is performed by pressing the processing tool 30 against the joint surface of one of the rotated joining materials 3 to expose the active surface, and the processing tool 30 of the other joining material 5 is moved by the operating arm 31. Then, the joint surface is cut. At this time, the operator can work while observing the internal situation through the peephole 28. When the activation work is completed, the processing tool 30 is stored in the processing tool storage chamber 29 as shown by the imaginary line so as not to interfere with the joining.

FIG. 5 shows another example of the physical activation method, in which a high-frequency voltage is applied by a high-frequency power source 33 between the bonding materials 3 and 5 inserted into an airtight chamber 10 and supported at a required distance. At the same time as the discharge is caused, the bonding material 3 is rotated to activate and smooth the bonding surface of the bonding material 3.5.

As described above, by activating the bonding surfaces in a vacuum atmosphere prior to bonding, more reliable and high-strength bonding becomes possible, and the range of types of materials that can be bonded can therefore be expanded.

Further, in the above embodiment, a case was explained in which the inside of the airtight chamber IO is maintained in a vacuum atmosphere, but similar bonding can also be performed by maintaining the inside of the airtight chamber IO in an inert gas atmosphere or an inert gas atmosphere containing 10 pp- or less of oxygen. be able to.

As mentioned above, the airtight chamber lO is made of bonding material 3.5
Since it only needs to have a small-capacity structure that locally surrounds the vicinity of the joint, it can be easily moved and used at various joint locations. The apparatus for creating a vacuum or inert atmosphere can be downsized, and the time required to create the atmosphere can also be shortened.

It should be noted that the friction welding method of the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] As explained above, according to the friction welding method of the present invention, various excellent effects as described below can be achieved.

(1) Since friction welding is performed in a vacuum or in an inert atmosphere, the joining surfaces are activated well,
Therefore, strong bonding is possible with small frictional force.

■ By reducing the frictional force, plastic deformation and deterioration of the material can be prevented.

(b) The device for applying frictional force can be made smaller and lighter.

■ The airtight chamber locally surrounds only the area near the bonding surface of the bonding material, reducing the time required to maintain the interior in a vacuum or inert atmosphere, making the device smaller and lighter. .

(V) Due to the miniaturization of the airtight chamber, it can be easily moved and used in various locations.

&D If the bonding surfaces are activated by a physical activation method prior to bonding, more reliable bonding becomes possible.

[Brief explanation of drawings]

FIG. 1 is a side view showing an example of an apparatus for carrying out the method of the present invention, FIG. 2 is a perspective view showing an example of an airtight chamber, and FIG.
The figure is a sectional view showing an example of a local sealing device, FIG. 4 is a cutaway front view showing an example of a device that performs a physical activation method using a processing tool, and FIG. 5 is an example of a physical activation method using an electric discharge. FIG. 6 is a side view showing an example of an apparatus for carrying out the conventional friction welding method, and FIG. 7 is a cross-sectional view of a joined part joined by the conventional friction welding method. 3 is a bonding material, 4 is a rotary chuck, 5 is a bonding material, 6 is a guide member, 7 is a fixed chuck, 8 is a pressing device, IO is an airtight chamber, 12 is a suction tube, 13 is a vacuum generator, 1
7. 18 is an insertion port, 19 is a local sealing device, 30 is a processing tool, 31 is an operating arm, and 33 is a high frequency power source. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1) In a friction welding method in which opposing joint surfaces of joining materials are joined by applying frictional force, the vicinity of the joining surfaces of the joining materials is hermetically surrounded by an airtight chamber, and the inside of the airtight chamber is in a vacuum or in an inert atmosphere containing an inert gas or 10 ppm or less of oxygen,
A friction welding method characterized in that the welding is performed by applying a frictional force to the joining surfaces. 2) In the friction welding method, in which opposing joint surfaces of joining materials are joined by applying frictional force, the vicinity of the joining surfaces of the joining materials is hermetically surrounded by an airtight chamber, and the inside of the airtight chamber is kept in a vacuum or inert. When kept in a gas or inert atmosphere containing 10 ppm or less oxygen,
A friction welding method characterized in that after the joining surfaces of the joining materials are activated by a physical activation method, frictional force is applied to the joining surfaces to join them.