JP2823411B2 - Diffusion bonding member manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to hot isostatic pressing (HI).
P) The present invention relates to a method for producing a diffusion bonding member which is easy to be practically used by ensuring initial hardness of a material to be processed having various shapes by diffusion bonding by processing.

[0002]

2. Description of the Related Art As a method of combining a plurality of members by solid-phase diffusion bonding, a method of rolling represented by the production of clad steel sheets is frequently used. According to rolling, diffusion bonding can be performed while maintaining the hardness, elasticity, and the like of the initial material, but if mass production is not possible, it is not practical from the viewpoint of economics, and it is not practical from the viewpoint of economics. There is a problem that a complicated product having irregularities cannot be manufactured. For example, the manufacture of magnetic head holding members and thin motor parts of disk drive devices of OA equipment or the integration of the hob and disk of a rotary encoder is performed by laser welding or spot welding, and when joint strength is required. The current situation is to respond to the problem by increasing the number of welding points.

[0003] In recent years, the HIP method has been used as a method for diffusion bonding such a member having a complicated shape. Here, the HIP method is a method in which a gas is used as a pressure medium and a uniform pressure is applied from all directions, together with the heating and heating.
In diffusion bonding by HIP, it is necessary to prevent gas from entering the surface to be bonded, and the entire material to be processed as shown in FIG. 6 is vacuum-sealed in a metal capsule and subjected to HIP processing. A method, such as a method shown in FIG. 7, in which the entire periphery of the joint surface is sealed in advance by welding and then subjected to HIP processing, or the like is used.

[0006] In the method shown in FIG.
2 (corresponding to (a) in the figure), and a capsule 3 and a deaeration pipe 4 are formed around this (see (b),
(Equivalent to (c)), after degassing the air inside the capsule 3 from the degassing pipe 4 (corresponding to (d) in the figure), cutting and welding the degassing pipe 4 to evacuate the inside of the capsule 3 (Corresponding to (e) in the figure), and this is subjected to HIP processing (corresponding to (f) in the figure). Also, in FIG.
, And the weld around the joint is shown at 6. When the material to be processed in the state of FIG. 7A is subjected to the HIP processing, a diffusion bonding member 7 (corresponding to (b) in the figure) is obtained.

[0005]

However, FIG. 6 and FIG.
In any of the methods described above, the HIP treatment itself is a heat treatment, and even if the cooling rate during cooling is high, 500 ° C./hr
Therefore, the obtained diffusion bonding member is in a state where it has been subjected to a halfway annealing treatment. For this reason, even if the diffusion bonding member obtained by the HIP processing has a low rigidity or the like, even if the diffusion bonding member obtained by the HIP processing has a rigidity or a hardness that can be used as a structural material after being work-hardened by cold rolling, the rigidity or the like is low. Therefore, even a material that has undergone work hardening by cold rolling softens in the process of HIP processing, loses its initial hardness or rigidity, and when used as a part, undergoes plastic deformation or permanent deformation when a large load is applied. May occur. Further, when manufacturing a plate-shaped diffusion bonding member, the spring property may be reduced and the practicality may be impaired. For example, in the case of stainless steel, it is impossible to improve the strength in the same manner as work hardening by heat treatment.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a diffusion bonding member having sufficient bonding strength, sufficient hardness or rigidity even in a complicated shape. It is to provide a method of manufacturing the.

[0007]

According to a method of manufacturing a diffusion bonding member of the present invention, a plurality of materials to be processed are superimposed and sealed in a capsule, and the capsule is subjected to hot isostatic pressing. The method includes a step of diffusion-bonding the processing material and a step of cold isostatic pressing the diffusion-bonded processing material at a fluid pressure equal to or higher than the yield point stress of the processing material.

[0008]

The plurality of superposed materials are diffusion-bonded by the HIP process, and at the same time, undergo a halfway annealing process, resulting in a decrease in hardness or rigidity. When the diffusion-bonded workpiece is subjected to cold isostatic pressing at a pressure equal to or higher than the yield stress of the workpiece, it undergoes isotropic plastic deformation. Therefore, the diffusion bonding member obtained after the cold isostatic pressing treatment is hardened by the isostatic pressing, and has an increased hardness or rigidity.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIG. FIG. 1 is a process chart showing a method of manufacturing a diffusion bonding member in which a workpiece 10 shown in FIG. 1A, that is, a metal plate member 11 with a window hole and a thin plate member 12 are overlapped and joined. . The material to be processed 10 is sandwiched between the two metal foils 13, 13, and the edges of the metal foil are welded to form a capsule 15 while leaving only a part of the end of the metal foil (FIG. 1B). . Welds are indicated at 14. Capsules 15 are formed at the ends of the metal foil that are not welded, so-called openings (not shown).
After vacuum degassing the inside, the opening is welded to seal the capsule 15. Next, this capsule 15 is
It is set in an apparatus and pressurized with a high-pressure gas at a high temperature to perform diffusion bonding of the materials to be processed 11 and 12 (FIG. 1C). FIG.
In (c), reference numeral 16 denotes a heater of the HIP device, and an arrow indicates a gas pressure. After the HIP processing, the metal foil as the capsule 15 is peeled off, and the diffusion-bonded material to be processed 10 ′ is taken out. The material to be treated 10 ′ is put into a cold isostatic pressing device, and cold isostatic pressing (CIP) is performed at a fluid pressure equal to or higher than the yield point stress of the material to be treated (FIG. 1D). ). FIG.
In (d), the arrow shows the fluid pressure.

When the workpieces 11 and 12 are diffusion-bonded as described above, a bonding member as shown in FIG. 2 is obtained. The materials to be processed 11, 12 may be the same material or different materials. When materials having significantly different coefficients of thermal expansion are used, it is preferable to insert an insert material having an expansion coefficient intermediate between the two materials to be processed. Further, the thickness of the processing target materials 11 and 12 is not particularly limited, but the thickness of the entire processing target material is 5 m.
In the case of m or less, especially 2 mm or less, the cost is high if it is manufactured by other methods such as rolling, so that the effect of the present invention is remarkable.

The metal foil 1 used for the capsule 15
The material of No. 3 is appropriately selected depending on the type of the material to be processed, the joining temperature, the availability, and the like. The thickness of the metal foil 13 varies depending on the size of the material to be processed, the material of the foil, and the like.
About 300 μm is preferable. In the vacuum encapsulation process in the step of FIG. 1B, the workpiece 11 and the workpiece 12 may be spot-welded in advance so that the positional relationship between the workpieces 11 and 12 does not shift. preferable. Further, in order to avoid diffusion bonding between the metal foil capsule 15 and the materials 11 and 12 in the HIP processing step of FIG. 1C, the capsule 15 inside the capsule 15 or in the materials 11 and 12 is processed. It is preferable to apply a ceramic release material to the contact surface with the mold.

The HIP processing conditions (temperature, pressure, time) in the step of FIG. 1 (c) are appropriately set according to the type and combination of the materials to be processed. Workpiece 10 'after HIP processing
However, even if the material to be processed 10 that has been work-hardened by cold rolling is used, the stiffness and the like are reduced because the HIP process results in a half-annealed state. FIG.
The material to be treated 10 ′ is isotropically cured by the CIP treatment in the step (d). Therefore, the hardness and rigidity are improved without substantially changing the shape of the material to be processed 10 '. The plate-shaped diffusion bonding member recovers the spring property. CIP
Conditions other than the processing pressure are appropriately selected depending on the type of the material to be processed.

In this embodiment, the capsule 15 is removed before performing the CIP process. However, the present invention is not limited to this.
CIP processing may be performed for each capsule. Further, in the above embodiment, the materials to be processed 11 and 12 are used, but the method of the present invention can also overlap and bond two or more materials to be processed. Further, the present invention can be applied to a material to be processed having irregularities. For example, a diffusion bonding member as shown in FIG. 3 can be manufactured by sandwiching a member 19 having a plurality of holes between two thin plates 18 and 20. Machine parts in which the ring-shaped members 22 are joined by a thin metal plate 23 can also be manufactured (see FIG. 4). 3 and 4, the joining surface is indicated by a broken line.

Further, a part of the material to be processed can also be used as a capsule. FIG.
5 shows a case where diffusion bonding is performed. In FIG. 5, instead of two metal foils for forming a capsule, a capsule is formed by a metal foil 26 and a material 25 to be processed. When applying a release material in such a case, the release material 28 is applied only to a contact portion between the metal foil capsule 26 and the workpiece 24. When removing the capsule, only the metal foil capsule 26 may be removed. In FIG. 5, reference numeral 27 denotes a weld. By using a part of the capsule as the material to be treated in this way, the cost can be reduced. In addition, the manufacturing method of the present invention can be applied to any material to be processed that can be subjected to the HIP treatment, but is particularly preferably applied to stainless steel. [Specific Examples] Example 1; SUS3 having a thickness of 0.1 mm was used as a material to be treated.
04 plate-shaped member with window hole and SUS3 with a thickness of 0.1 mm
The thin plate member made of 04 was diffusion bonded by the method shown in FIG. 1 under the HIP processing conditions and the CIP processing pressure shown in Table 1 to obtain a diffusion bonded member as shown in FIG. The obtained diffusion bonding member is bonded and integrated over the entire bonding surface. Table 1 shows the hardness of the diffusion bonding member after the HIP treatment and the hardness after the CIP treatment. The hardness is represented by Vickers hardness (Hv).

The yield point stress of SUS304 is 23
It is 00 to 2700 kgf / cm ² . Examples 2 to 4: Diffusion bonding members were obtained in the same manner as in Example 1 except that the HIP processing conditions, the CIP processing pressure, and the materials to be processed were changed as shown in Table 1. Example 3
Only a diffusion bonding member having the shape shown in FIG. 3 was obtained. Table 1 shows the hardness of the diffusion bonding member after the HIP treatment and the hardness after the CIP treatment of each example.

Incidentally, the yield point stress of SPCC is 2300
２2700 kgf / cm ² . Comparative Examples 1 to 3: The same as Example 1 except that the HIP processing conditions, the CIP processing pressure, or the material of the material to be processed were changed as shown in Table 1. Table 1 shows the hardness of the diffusion bonding member after the HIP treatment and the hardness after the CIP treatment.

[0017]

[Table 1]

[Evaluation Results] As can be seen from Table 1, HI
After the P treatment, the material subjected to the CIP treatment at a pressure equal to or higher than the yield point stress of the material to be treated (Examples 1 to 4) has improved hardness after the CIP treatment, but the CIP treatment has a pressure less than the yield point stress of the material to be treated. For those obtained (Comparative Examples 1 to 3), almost no improvement in hardness was observed before and after the CIP treatment.

[0019]

According to the manufacturing method of the present invention, the material to be processed can be diffusion-bonded not only in the shape of a thin plate but also in various shapes, and the obtained diffusion-bonded member is the same as in the case of manufacturing the diffusion-bonded member by rolling. In addition, the initial rigidity and hardness of the material to be processed can be secured. Therefore, by the manufacturing method of the present invention, a complex mechanical part having sufficient rigidity, hardness and bonding strength, for example,
A magnetic head holding member and a thin motor component of a disk drive device of an OA device can be manufactured. Further, plate-like products having different wall thicknesses which were difficult with the conventional method, for example, a thin plate-like diffusion bonding member such as a filter in which a wire mesh is bonded and fixed to a metal frame or a blade of an electric razor which wants to ensure spring properties, It can be manufactured by the manufacturing method of the present invention.

[Brief description of the drawings]

FIG. 1 is a process chart showing one embodiment of a manufacturing method of the present invention.

FIG. 2 is an embodiment of a diffusion bonding member manufactured by the manufacturing method of the present invention.

FIG. 3 is another embodiment of the diffusion bonding member manufactured by the manufacturing method of the present invention.

FIG. 4 is another embodiment of the diffusion bonding member manufactured by the manufacturing method of the present invention.

FIG. 5 is another embodiment of the diffusion bonding member manufactured by the manufacturing method of the present invention.

FIG. 6 is a diagram showing steps of a conventional method for manufacturing a diffusion bonding member.

FIG. 7 is a diagram showing steps of a conventional method for manufacturing a diffusion bonding member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Processing material 10 'Diffusion-bonded processing material 11 Plate member with a window hole 12 Thin plate member 15 capsule

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B23K 20/00

Claims (4)

(57) [Claims] 1. A process in which a plurality of materials to be treated are superimposed and sealed in a capsule, the capsule is subjected to hot isostatic pressing, and the material to be treated is diffusion-bonded. A method for manufacturing a diffusion bonding member, comprising a step of subjecting a material to cold isostatic pressing at a fluid pressure not lower than the yield point stress of the material to be processed. 2. The method according to claim 1, wherein the plurality of materials to be processed are all the same. 3. A capsule having a thickness of 30 to 300 μm.
The method for producing a diffusion bonding member according to claim 1, wherein the metal foil is used. 4. The method for producing a diffusion bonding member according to claim 1, wherein the capsule forms a part of the diffusion bonding member.