JP2782630B2 - Room temperature solid state bonding - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a room-temperature solid-state bonding method capable of bonding in a solid state at room temperature (a temperature at which a material does not deteriorate).
A non-metallic material, a superconducting material, or the like can achieve high bonding strength without causing a change or deformation of the material.

[Prior art] The solid-phase joining method is a method of joining a solid phase without melting a joint, and compared with a brazing method in which a joining metal is joined by adding a molten metal in which a joint generally melts in a wide range. There are few portions that are deteriorated in material such as a solidified structure and a heat-affected zone in the joint, and it is particularly suitable for joining dissimilar materials that are likely to be weakly joined by fusion welding.

The main currently used solid-phase bonding methods include a pressure welding method and a diffusion bonding method.

Among these, the pressure welding method is a method in which mechanical pressure is applied to a joint to cause plastic deformation to join the joints, and has a feature that the apparatus is inexpensive and easy to operate.

In addition, the diffusion bonding method is a method in which a smooth surface is brought into contact with each other and held at a high temperature and bonded by interdiffusion of atoms. ing.

However, in the pressure welding method, it is necessary to apply a large force that causes plastic deformation at the joint, and therefore there is a problem that it is not suitable for joining materials to be joined, which dislikes material deformation.

On the other hand, in the diffusion bonding method, only a slight pressure is applied by bringing the bonding surfaces into contact with each other, and no large deformation occurs, but the bonding portion is kept at a high temperature of about 800 to 1200 ° C. (70 to 90% of the melting point). In addition, there is a problem that the material must be held for a long time in order to cause the atoms to interdiffuse, resulting in deterioration of the material due to the influence of heat.

 For this reason, a room-temperature solid-state bonding method has recently been proposed.

The room-temperature solid-state bonding method uses a high or ultra-high vacuum state (10 ^-4 P
a) or a mechanical activation method using rotational friction, ultrasonic vibration, etc., or a physical activation method using electric discharge, etc., in an inert atmosphere containing an inert gas or oxygen of 10 ppm or less. Cleaning and activation, and then joining by pressure welding.

[Problems to be Solved by the Invention] However, when materials are joined by the above-mentioned room temperature solid-state joining method, if the opposing joining surfaces are smooth surfaces that exactly match each other and are activated surfaces, high strength is obtained. Although bonding is possible, the normal bonding surface has irregularities, is contaminated, and foreign matter is interposed, so that voids remain in the bonding part, and the bonding strength of the bonding part due to this void Had a problem of drastically decreasing.

An object of the present invention is to provide a room-temperature solid-state bonding method that can prevent voids from remaining on a bonding surface and obtain high bonding strength.

[Means for Solving the Problems] The present invention provides a counterbore portion on at least one of bonding surfaces of materials to be bonded, leaving a peripheral portion, and forming the material at room temperature with an inert gas or 10 ppm or less. After activating the bonding surface in an atmosphere of an inert gas containing oxygen, or in a high-temperature or ultra-high vacuum state at room temperature, by pressing the bonding surfaces of the materials together at room temperature, Temporary joining, and then subject to the room temperature solid-state joining method characterized by performing HIP treatment at a temperature of about 350 ° C. or less and crushing the closed space created on the joining surface by the temporary joining to complete joining. is there.

[Operation] A spot facing portion is formed on at least one of the joining surfaces of the materials to be joined, leaving a peripheral edge portion.

In a state where the above-mentioned material is kept in an atmosphere of an inert gas containing an inert gas or oxygen of 10 ppm or less at room temperature, or a room temperature atmosphere in a high or ultra high vacuum state, the bonding surface is subjected to a mechanical activation method or physical properties. Activated by a selective activation method.

Subsequently, temporary joining is performed by pressing the joining surfaces of the materials together in the atmosphere.

Thereafter, HIP processing is performed to crush the sealed space created on the bonding surface by the temporary bonding, thereby performing complete bonding.

As a result, no void remains at the joint,
High bonding strength can be obtained.

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

According to the present invention, the bonding strength of a material can be remarkably improved by combining a room-temperature solid-state bonding method with a HIP treatment.

1 and 2 show an example of a material for carrying out the room-temperature solid-state bonding method of the present invention.
2 has a cylindrical shape, and at least one of the joining surfaces 3 of the materials 1 and 2 has a depth of about 0.1 to 2 mm at the center while leaving an outer edge joining surface 3 'having a required width on the outer peripheral portion. A flat counterbore 4 is formed.

FIG. 3 shows an example of a temporary joining device 5 for activating and temporarily joining the joining surfaces 3 of the materials 1 and 2, and in the drawing, reference numeral 6 denotes an airtight container. An inert gas replacement device 7 that supplies an inert gas such as Ar to replace the inside of the airtight container 6 with an inert gas atmosphere is provided.

In the airtight container 6, each of the materials 1 and 2 is held such that the joining surfaces 3 face each other, and the materials 1 and 2 are driven to rotate in opposite directions on the same axis. Sample holders 8 and 9 are provided.

The sample holder 8 is rotatably supported by a fixed rotating device 10 which is fixed, and the sample holder 9 is provided on a movable table 11 which is movable in the axial direction A of the materials 1 and 2. It is rotatably supported by the side rotation device 12, and the movement and movement of the moving table 11 enable the contact and press contact of the joining surfaces 3 of the materials 1 and 2.

Further, a high-frequency power source 13 for generating a high-frequency discharge between the joining surfaces 3 of the materials 1 and 2 is provided.

FIG. 5 shows an example in which the integrated temporary bonding material 14 (see FIG. 4) is accommodated by temporary bonding by the temporary bonding device 5 in FIG. 3, and HIP processing is performed by the action of a required temperature and high pressure. The pressure vessel 16 for obtaining the joining material 15 (see FIG. 6) is shown.

 Next, an example of the case of actually joining will be described.

In a state in which the inside of the airtight container 6 shown in FIG. 3 is open to the atmosphere, as shown in FIGS.
The material 1 and the material 2 having the above are attached to the sample holders 8 and 9 respectively, and the moving table 11 adjusts the mutual distance between the joining surfaces 3 of the materials 1 and 2.

In this state, the airtight container 6 is
After a high-purity argon gas atmosphere having an oxygen concentration of 10 ppm or less, a high-frequency voltage from a high-frequency power supply 13 is applied between the materials 1 and 2 in the high-purity argon gas atmosphere, and the bonding surface is sputtered by a discharge. Remove and activate 3 contaminated layers. High frequency voltage is peak voltage 15 ~
25 KV and a discharge cycle of 3 to 4 μs are used.

Further, at this time, high-frequency discharge is performed while rotating the materials 1 and 2 in directions opposite to each other so as to uniformly activate the entire bonding surface 3.

After activating the bonding surface 3 of the materials 1 and 2 in this manner, moving the movable table 11 while the materials 1 and 2 are rotated or stopped in the inert gas atmosphere. Thereby, the joining surfaces 3 of the materials 1 and 2 are brought into contact with each other and pressurized to join them.

As described above, the temporary bonding material 14 bonded as shown in FIG. 4 is in a temporary bonding state in which only the outer edge bonding surface 3 ′ is bonded, and has a sealed space 17 closed by the counterbore 4 inside.
Remains.

Subsequently, the temporary bonding material 14 was transferred to a pressure vessel 16 shown in FIG.
And perform HIP processing. For example, here at 350 ° C
By holding for about 2 hours under an argon atmosphere at a pressure of 850 to 1000 kgf / cm ² below, the closed space 17 in the non-bonded state at the center of the bonding surface 3 is crushed and cut to complete bonding. Is performed to obtain the bonding material 15 as shown in FIG.

That is, by heating in a high-pressure argon atmosphere, metal atoms diffuse into the closed space 17 and eventually fill the entire closed space 17 so that the closed space 17 by the counterbore 4 is also completely metallic. Will be joined.

In the above, if the airtight container 6 shown in FIG. 3 has a function as a pressure container, the inside of the airtight container 6 shown in FIG. 3 can be prepared without preparing a new pressure container 16 as shown in FIG. In the above, the temporary joining and the HIP treatment can be performed continuously.

In the above embodiment, the case where the temporary bonding is performed in an argon atmosphere has been described. However, the temporary bonding may be performed in an atmosphere in a high or ultra-high vacuum state.

Further, the case where the high-frequency discharge is used as a method for activating the bonding surfaces 3 of the materials 1 and 2 has been described, but the activation may be performed using another method.

For example, FIG. 7 shows the material without the high-frequency discharge.
The case where the materials 1 and 2 are rotated in opposite directions while the joining surfaces 3 of 1 and 2 are pressed against each other and activated by frictional force is shown.

FIG. 8 shows a case in which vibration is applied to the materials 1 and 2 by the ultrasonic vibrator 18 in a state where the joining surfaces 3 of the materials 1 and 2 are pressed against each other, and activation is performed by a frictional force.

Further, FIG. 9 shows that a cutting and polishing tool 19 such as a file is held between the joining surfaces 3 of the materials 1 and 2, and in this state, the materials 1, 2
In this case, a method of rotating the laser beam or a method of providing an ultrasonic vibrator is performed to cut and activate the bonding surface 3. In addition to this method, by using a cutting tool such as a cutting tool or a grindstone to cut the bonding surface 3
Can also be activated.

According to the room-temperature solid-state bonding method described above, after the temporary bonding by the activated bonding surface 3 is performed, the entire bonding surface is completely bonded by the HIP process, so that no void is generated in the bonding portion. , Very high bonding strength can be obtained.

In addition, the above-mentioned room temperature solid-state bonding method uses a material that is easily deformable and cannot apply a large pressing force when the materials 1 and 2 are pressed and bonded, or a uniform pressing force with a large bonding area and a large bonding surface. It can be used effectively for joining materials that cannot be applied.

The room-temperature solid-state bonding method of the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the scope of the present invention.

[Effects of the Invention] As described above, according to the room-temperature solid-state bonding method of the present invention, the above-described material having a counterbore portion formed on at least one of the bonding surfaces of the materials to be bonded, while leaving a peripheral edge portion, In the atmosphere of an inert gas containing an inert gas or oxygen of 10 ppm or less, or after activating the bonding surface in a state of being held in an atmosphere of a high or ultra-high vacuum state, the bonding surfaces of the material Temporary joining is performed by pressing, then HIP processing is performed, and the closed space created on the joining surface by the temporary joining is crushed so that perfect joining is performed, so that voids are not left at the joining part of the material High bonding strength can be obtained.

Also, by forming the counterbore portion, it is only necessary to perform the joining of the peripheral joining surfaces when performing the temporary joining, so that the pressure contact force can be reduced, so that the deformable material and the joining surface are large and the entire joining surface is large. It can be applied effectively when uniform pressure welding is difficult.

[Brief description of the drawings]

FIG. 1 is a side view showing the shape of a material used in the room temperature solid-state bonding method of the present invention, FIG. 2 is a view taken along the line II-II of FIG. 1, and FIG. 3 is an example of a temporary bonding apparatus used in the present invention. FIG. 4, FIG. 4 is a side view of a temporary bonding material, FIG. 5 is a cross-sectional view of a pressure vessel for performing HIP processing used in the present invention, FIG. 6 is a side view of a completely bonded bonding material, 7 to 9 show another example of a method of activating a bonding surface, FIG. 7 is a diagram showing an example using rotational friction, and FIG. 8 is a diagram showing an example using an ultrasonic vibrator. ,
FIG. 9 is a diagram showing an example using a file plate. 1, 2 is a material, 3 is a joining surface, 3 'is a peripheral joining surface, 4 is a counterbore portion, 5 is a temporary joining device, 6 is an airtight container, 7 is an inert gas replacement device, 8, 9 are sample holders, 10 is a fixed side rotating device, 11
Is a moving table, 12 is a moving side rotating device, 13 is a temporary joining material, 15 is a joining material, 16 is a pressure vessel, 17 is a closed space, 18 is an ultrasonic vibrator, 19 is a cutting and polishing tool such as a file, etc. .

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuyuki Tsuchiya 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Technical Research Institute of Ishikawajima-Harima Heavy Industries Co., Ltd. 1 Haramachi Ishikawajima-Harima Heavy Industries, Ltd. Technical Research Institute (56) References JP-A-61-30292 (JP, A) JP-A-48-76761 (JP, A) JP-A-63-286288 (JP, A) ( 58) Field surveyed (Int.Cl. ⁶ , DB name) B23K 20/00-20/24

Claims (1)

(57) [Claims] 1. A counterbore portion is formed on at least one of the joining surfaces of a material to be joined, leaving a peripheral portion, and the material is placed at room temperature in an atmosphere of an inert gas or an inert gas containing 10 ppm or less of oxygen. , Or after activation of the bonding surface in a state of being held in a high or ultra-high vacuum state at room temperature, temporarily bonding by pressing the bonding surfaces of the materials together at room temperature, and thereafter 350 ° C. or less A room-temperature solid-state bonding method, wherein HIP processing is performed at about a temperature, and a closed space created on the bonding surface by the temporary bonding is crushed to perform complete bonding.