JP2760111B2 - Friction welding method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a friction welding method.

[Prior Art] The friction welding method is a method in which joining materials are brought into contact with each other to perform a relative rotational motion, and joining is performed using frictional heat generated on the joining surface.

FIG. 9 shows an example of an apparatus for carrying out a conventional friction welding method, which is attached to a flywheel 2 which is rotated by an electric motor 1 and which rotates by clamping one of the joining materials 3; A fixed chuck disposed on the same axis as that of the rotary chuck 4 so as to clamp the other bonding material 5 so as to face the bonding material 3 and to be able to approach and separate from the rotary chuck 4 along a guide member 6 7 and
A pressing device 8 including a hydraulic cylinder or the like that moves the fixed chuck 7 to press the bonding materials 3 and 5 against each other is provided.

While the rotating chuck 4 to which one of the joining materials 3 is attached is rotated at a constant rotation speed, the fixed chuck 7 to which the other joining material 5 is attached is advanced by the pressing device 8 so that the joining materials 3 and 5 are joined. When the surfaces are pressed against each other, the friction portion becomes red and softened, and the rotational energy is consumed by the generation of heat, so that the rotational motion is rapidly decelerated, spontaneously stopped, and the pressing is completed. In the above, a method is also adopted in which when the friction portion has reached an appropriate temperature, the rotation is stopped by applying a brake.

Generally, the pressing pressure after the rotation is stopped is maintained as it is as the upset pressure, or the pressure is further increased to perform the upset.

At the time of the above-mentioned friction welding, an oxide that hinders the welding on the welding surface,
Since there is a thin gas adsorption film, dirt, etc., these are decomposed during friction or are pushed out as a burr 9 from the bonding portion to the outside by a large pressing force as shown in FIG. Usually, the temperature of the friction portion in the conventional method rises to just below the melting point of the material.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional method, in order to activate the bonding surface and obtain a strong bonding, bonding is performed by pressing with a strong pressing force. Generally joining materials
If the materials 3 and 5 are relatively soft materials such as aluminum and copper, they tend to be joined easily, and if they are relatively hard materials such as titanium, stainless steel and ceramics, they tend to be difficult to join.

For this reason, there is a problem that the range of types of materials that can be joined is narrow, and even if joining can be performed, sufficient joining strength cannot be obtained.

Therefore, conventionally, as for the material which cannot be joined by friction joining, as shown in FIG. 11, a plate-shaped or thin-film insert material S is arranged on the joining surfaces of the joining materials 3 and 5, and the whole is heated at a high temperature. When they are heated, they are joined by diffusion bonding or by melting and brazing.

However, the above-mentioned diffusion bonding or brazing method has a problem that the bonding materials 3 and 5 are deteriorated because of heating to a high temperature, or requires a large-scale apparatus for heating to a uniform temperature. There was a problem that it took time to heat.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is a friction joining method which enables a joining material such as a hard material which could not be joined by the conventional friction joining method to be easily and firmly joined. It is intended to provide.

Means for Solving the Problems According to the present invention, in a friction joining method of joining joining materials that are difficult to join by applying a frictional force to opposing joining surfaces of the joining material, a soft intermediate material is added to the first joining material. In the state where the vicinity of the contact surface where one end is brought into contact with the contact surface is hermetically surrounded by an airtight chamber, and the inside of the airtight chamber is maintained in a vacuum or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less, The joining surfaces are joined by applying a frictional force. Subsequently, a second joining material is brought into contact with the other end of the intermediate material, and the vicinity of the joining surface in contact is airtightly surrounded by an airtight chamber. A friction welding method characterized by applying a frictional force to the joining surface in a state of being held in a vacuum, or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less, or joining. In a friction joining method in which joining materials that are difficult to join by applying frictional force to joining surfaces of materials that are opposed to each other, one end of a soft intermediate material is brought into contact with the first joining material and the vicinity of the joining surface in contact with the first joining material. Was hermetically surrounded by an airtight chamber, and the bonding surface was activated by a physical activation method in a state where the inside of the airtight chamber was kept under vacuum or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less. rear,
The joining surfaces are joined by applying a frictional force. Subsequently, a second joining material is brought into contact with the other end of the intermediate material, and the vicinity of the joining surface in contact is airtightly surrounded by an airtight chamber. Vacuum inside, or inert gas or 10ppm
After activating the bonding surface by a physical activation method in a state of being kept in an inert atmosphere containing the following oxygen, a friction bonding method characterized by applying a frictional force to the bonding surface to perform bonding. Such is the case.

[Operation] When frictionally joining joining materials that are difficult to join, a soft intermediate material is joined to the first joining material by friction joining, and then a second joining material is joined to the intermediate material by friction joining. And, by performing the friction joining in a vacuum or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less, the joining surface is activated well, and strong joining can be performed with a small frictional force. Become. Since the joining can be performed with the small frictional force, plastic deformation and deterioration of the joining material can be prevented, and the device structure for applying the frictional force can be reduced in size and weight.

Further, if the bonding surface is activated by a physical activation method before the bonding, a more reliable bonding can be achieved.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In the present invention, as shown in FIG. 1, the first and second joining materials 34 and 35 which are hard to be joined, such as a hard material, are joined together by forming a soft intermediate material 36 having a required length therebetween. This is intended to be made possible by friction joining by intervening.

FIG. 2 is an example of an apparatus for performing the method of the present invention,
In the figure, the portions denoted by the same reference numerals as those in FIG. 9 represent the same items.

As shown in FIG. 2, the rotary chuck 4 and the fixed chuck 7
A hermetic chamber 10 is provided on a support base 11 so as to hermetically surround the outer periphery of the bonding material in a required direction in the length direction, and a vacuum is generated in the hermetic chamber 10 via a suction pipe 12. The device 13 is connected.

FIG. 3 shows an example of the airtight channeler 10.
The hermetic chamber 10 is composed of two boxes 15 and 16 having a split structure that can be assembled with a flange portion 14 provided at the open end, and is provided at the bottoms 15 'and 16' of the boxes 15 and 16. In the figure, insertion ports 17 and 18 are formed on the same axis, and a local sealing device 19 is attached to the insertion ports 17 and 18.

As shown in FIG. 4 by taking the box body 15 as an example, the local sealing device 19 is provided on the outside of the bottom 15 'in which the insertion port 17 is formed.
A support metal fitting 21 that forms an annular concave space 20 whose inner side in the radial direction is open 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 annular seal member 26 having a substantially C-shaped cross section so as to form the inner seal plate 24 and the outer seal plate 25.
The seal member 26 is made of a synthetic resin material having a required elastic deformation capability and high wear resistance.

An annular coil spring 27 having a high elastic force is inserted into the C-shaped inside of the seal member 26.

In the above-described configuration, the inner diameter of the seal body 23 is slightly smaller than the outer diameter of the bonding material (34 in the drawing) for sealing. Therefore, when the bonding material 34 is pushed into the inside of the seal body 23, it is pressed. The inner seal plate 24 is expanded and the coil spring 27 is crushed as shown in FIG. 4, so that the inner seal plate 24 becomes the bonding material 34 and the outer seal plate 25 becomes the support fitting 21. Strong sealing is ensured by being strongly pressed.

In addition, on the side surface of the box 15 in the hermetic chamber 10, a viewing window 28 from which the alignment and the bonding state of the bonding materials 34 and 36 can be monitored from outside the hermetic chamber 10.
Is provided.

First and second bonding materials 34,3 used in the method of the present invention
5 and the intermediate material 36 are all formed to have the same diameter.

One end of a hard first bonding material 34 is inserted into the insertion port 17 provided with the local sealing device 19 of the airtight chamber 10 shown in FIG. 3, and one end of a soft intermediate material 36 is inserted into the other insertion port 18. Then, the other ends of the two materials 34 and 36 are attached to the rotary chuck 4 and the fixed chuck 7 in a state of being centered as shown in FIG. At this time, the airtight chamber 10 is supported on the support base 11 so as not to rotate.

Subsequently, suction is performed by the vacuum generator 13 to maintain the inside of the airtight chamber 10 at a vacuum.

In this state, the electric motor 1 is driven to rotate the rotary chuck 4 and the first joining material 34 via the flywheel 2, and further, the fixing chuck 7 is advanced by the pressing device 8, and the intermediate material is moved.
The bonding surface of 36 is pressed against the bonding surface of the first bonding material 34.

Then, the joining surface is immediately activated by friction due to the vacuum atmosphere, and therefore, is firmly joined with a small pressing force and a low friction temperature.

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

Next, after releasing the vacuum state in the hermetic chamber 10, the clamping position of the first bonding material 34 with respect to the rotary chuck 4 is changed as shown in FIG. So that the joining surface of the second joining material 35 and the joining surface of the other end of the joined intermediate material 36 face each other, and the airtight chamber is surrounded so as to surround the vicinity of the facing joining surface. After positioning the position 10, the inside of the airtight chamber 10 is again kept at a vacuum, and bonding is performed in the same manner as described above.

As described above, the soft intermediate material 36 is interposed between the first and second joining materials 34 and 35, and the joining is performed while performing the activation in a vacuum atmosphere. Even with a joining material, friction joining can be easily and firmly performed.

The bonding material that was bonded as described above is chuck 4,
7 and can be pulled out of the hermetic chamber 10 and taken out.
10 can be split into two and taken out.

Prior to the joining, the joining materials 34 and 35 and the intermediate material 3
By positively activating the bonding surface 6 by a physical activation method in a vacuum atmosphere, a stronger bonding can be easily and stably obtained.

FIG. 7 shows an example of the physical activation method, in which a processing tool storage chamber 29 is provided on the side of the airtight chamber 10 opposite to the view window 28, and the airtight chamber 10 is provided.
An operation arm 31 fixed to a processing tool 30 made of a file, diamond polishing or the like provided in the inside, an arm formed on the outer wall of the processing tool storage chamber 29 with the same local sealing device 19 as described above. The insertion hole 32 is inserted.

In this case, the processing tool is attached to the bonding surface of the first bonding material 34 or the intermediate material 36 which is rotatably supported by the rotary chuck 4.
30 is pressed to make the active surface come out, and the intermediate material 36 or the second material
The joining surface of the joining material 35 is activated by moving the processing tool 30 by the operation arm 31 and performing cutting. At this time, it is possible to perform the work while viewing the internal situation from the viewing window 28. When the activation operation is completed, the processing tool 30 is stored in the processing tool storage chamber 29 as shown by a virtual line so as not to disturb the joining.

FIG. 8 shows another example of the physical activation method, in which a high-frequency voltage is applied by a high-frequency power supply 33 between, for example, bonding materials 34 and 36 which are inserted into the hermetic chamber 10 and supported at a required interval. At the same time as applying and discharging, the joining material 34 is rotated to activate and smooth the joining surfaces of the joining materials 34 and 36.

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

Further, in the above-described embodiment, the case where the inside of the airtight chamber 10 is maintained in a vacuum atmosphere has been described, but the same bonding may be performed by maintaining the inside of the airtight chamber 10 in an inert gas atmosphere containing an inert gas or oxygen of 10 ppm or less. Can be.

As described above, the airtight chamber 10 only needs to have a small-capacity structure that locally surrounds the vicinity of the joining portion of the joining material, so that it can be easily moved to various joining locations as a compact structure and used. Since it is possible and has a small capacity, it is possible to reduce the size of a device for making the inside of the hermetic chamber 10 a vacuum or an inert atmosphere, and to shorten the time required for forming the atmosphere.

Incidentally, the friction joining method of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

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

(I) After bonding a soft intermediate material to the first bonding material, a second bonding material is bonded to the intermediate material, and the bonding is preferably activated in a vacuum or an inert atmosphere. Therefore, it is possible to perform the joining by the friction joining of the joining material which is difficult to join, so that the range of the types of materials that can be joined is greatly expanded.

(Ii) According to the above (i), strong joining can be performed with a small frictional force, and plastic deformation and deterioration of the material can be prevented.

(Iii) Since it can be carried out by a small airtight chamber, the airtight chamber can be moved and used easily in various places.

(Iv) If the bonding surface is activated by a physical activation method prior to the bonding, more reliable bonding can be achieved.

[Brief description of the drawings]

FIG. 1 is a side view of a material showing the principle of the friction welding method of the present invention, FIG. 2 is a side view showing an example of an apparatus for performing the method of the present invention, and FIG. 3 is a perspective view showing an example of an airtight chamber. ,
FIG. 4 is a cross-sectional view showing an example of the local sealing device, FIG. 5 is a side view showing the joining between the joining material of the present invention and the intermediate material, and FIG. 6 is the joining between the intermediate material and the second joining material. FIG. 7 is a cut-away front view showing an example of an apparatus for performing a physical activation method using a processing tool, FIG. 8 is a side view showing an example of a physical activation method using electric discharge, and FIG. FIG. 10 is a side view showing an example of an apparatus for performing a conventional friction welding method, FIG. 10 is a cross-sectional view of a joining portion joined by the conventional friction welding method, and FIG. 11 is a side view of the conventional diffusion welding or brazing. FIG. 4 is a rotary chuck, 6 is a guide member, 7 is a fixed chuck,
8 is a pressing device, 10 is an airtight chamber, 12 is a suction tube, 13 is a vacuum generating device, 17 and 18 are insertion ports, 19 is a local sealing device, 3
0 denotes a processing tool, 31 denotes an operation arm, 33 denotes a high-frequency power supply, 34 denotes a first bonding material, 35 denotes a second bonding material, and 36 denotes an intermediate material.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takehiro Murayama 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Pref. Ishikawajima-Harima Heavy Industries Co., Ltd. (56) References JP-A-59-47077 (JP, A) JP-A-62-282791 (JP, A) JP-A-1-148481 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23K 20/12-20/14

Claims (2)

(57) [Claims] In a friction joining method for joining joining materials which are difficult to join by applying a frictional force to opposing joining surfaces of the joining material, one end of a soft intermediate material is brought into contact with the first joining material. The vicinity of the contacted contact surface is hermetically surrounded by an airtight chamber, and a frictional force is applied to the joint surface in a state where the inside of the airtight chamber is kept in a vacuum or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less. Then, a second bonding material is brought into contact with the other end of the intermediate material, and the vicinity of the bonding surface in contact is air-tightly surrounded by an air-tight chamber, and the inside of the air-tight chamber is evacuated or inert gas. Alternatively, a friction joining method is characterized in that the joining surfaces are joined by applying a frictional force in a state where the joining surfaces are maintained in an inert atmosphere containing 10 ppm or less of oxygen. 2. A friction joining method for joining joining materials that are difficult to join by applying frictional force to opposing joining surfaces of the joining material, wherein one end of a soft intermediate material is brought into contact with the first joining material. The vicinity of the contacted contact surface is hermetically surrounded by an airtight chamber, and the joint surface is physically activated in a state where the inside of the airtight chamber is kept in a vacuum or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less. After the activation by the method, the joining surfaces are joined by applying a frictional force, and then the second joining material is brought into contact with the other end of the intermediate material. After airtightly surrounding and activating the bonding surface by a physical activation method in a state where the airtight chamber is kept in a vacuum or an inert atmosphere containing an inert gas or oxygen of 10 ppm or less, And a frictional joining method wherein a frictional force is applied to the joining surfaces for joining.