JP2002263857A - Method for manufacturing metal precision mechanical component and metal precision mechanical component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for inexpensively manufacturing a metal precision mechanical component which is assembled and formed by liquid phase diffusion welding by simplified manufacturing processes and a metal precision mechanical component. SOLUTION: In the method for manufacturing divided components for the metal precision mechanical component having a transporting path through which liquid or gas in a pipe line or a cylinder passes, respective outer shapes of the divided component which are divided into several pieces at an arbitrary surface in the axial direction of the transporting path are successively formed by forging or pressing, and thereafter the transporting path through which the liquid or gas in the pipe line or the cylinder passes is die forged by at least one time forging or pressing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various kinds of mechanical parts manufactured by using a liquid phase diffusion bonding technique, and more particularly, to machining such as cutting, shaving, punching, and die cutting from a raw material, or directly to molten metal. TECHNICAL FIELD The present invention relates to a machine component manufactured by liquid phase diffusion bonding instead of machining of a machine component having an annular or hollow shape by forging or forging or the like, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, it has an annular or hollow shape,
In particular, mechanical parts, such as bearings of rotating parts, bearings, and sliding pipes of cylinders, for which various properties such as wear resistance, corrosion resistance and fatigue resistance are individually or simultaneously required for a long time, are required quality. For example, in a bearing steel represented by JIS-SUJ, which has a relatively high alloy ratio, in addition to C: 1% and Cr: 1%, Mn,
Although a steel material containing Mo is used, it is often difficult to assemble parts by welding or the like. For this purpose, machine parts with complex shapes are cut out of massive steel ingots or roughly formed by hot forging or drilling, and after finishing, spheroidizing and carburizing according to required specifications. And manufacturing. Therefore, the cost of various processing steps in the manufacturing process accounts for the majority of the product price, rather than the price of the raw material ingot. On the other hand, precision mechanical parts, such as automobiles, which require high reliability are also required to have long-term durability, and are aimed at reducing specification costs over a long period of time. Therefore, even if expensive, these precision machine parts manufactured from the bulk metal by the conventional manufacturing method are frequently used, and this causes an increase in the price of many parts and eventually the price of the final product.

[0003] Of the methods of processing a metal material into an arbitrary shape, hot rolling and press molding are generally employed as methods with the highest mass productivity and low cost. It has a simple shape, often a simple shape such as a plate, and is suitable for mass production.However, it is not possible to directly manufacture hollow machine parts and annular parts with high yield by the above-mentioned rolling and press molding. It is difficult due to the shape restrictions, and it is currently not industrialized at all. Accordingly, there is no industrially established technology for efficiently mass-producing complicated precision mechanical parts having a ring or hollow shape, and on the other hand, there is an aspiration to develop a completely different manufacturing process from the viewpoint of cost reduction. Have been.

On the other hand, recently, the technique of liquid phase diffusion bonding has been spotlighted. This liquid-phase diffusion bonding technique uses an alloy having a lower melting point compared to the material to be bonded, for example, 50% or more of the crystal structure is substantially amorphous in the bonding surface of the material to be bonded, that is, between the grooves. Melting point of a low-melting-point alloy in which a joint is inserted by interposing a multi-element alloy, such as B, P, C, Si, Ni, Fe, etc., which is a material and has the ability to form a joint through a diffusion-controlled isothermal solidification process This is a technique of forming a joint in the isothermal solidification process by heating and holding at the above temperature. The liquid-phase diffusion bonding technique has a feature that, unlike the ordinary welding technique, there is almost no welding residual stress, or a smooth and precise joint that does not generate a margin like welding can be formed. Moreover, since this technique is a face joining, it has an advantage that the joining time is constant irrespective of the area of the joining surface and the joining is completed in a relatively short time, and is a joining technique completely different from the conventional welding. Therefore, if the temperature can be maintained at a temperature equal to or higher than the low melting point joining metal in which the groove is inserted for a predetermined time, bonding between surfaces can be realized regardless of the groove shape. On the other hand, with respect to conventional liquid phase diffusion bonding that can be realized only in a non-oxidizing atmosphere, an alloy foil for liquid phase diffusion bonding that can be applied even in an oxidizing atmosphere is known. (Japanese Patent No. 1891618
No. 1891619 and No. 1837572). However, at present, this liquid phase diffusion bonding technique is applied only to the bonding of members having a relatively large bonding surface area, and is not used for bonding precision mechanical parts and the like.

[0005]

SUMMARY OF THE INVENTION The present invention provides a complex precision machine part having an annular or hollow shape, which simultaneously satisfies various characteristics of wear resistance, corrosion resistance and fatigue resistance, with high efficiency and low cost. It is an object of the present invention to provide a metal precision machine component by diffusion bonding that can be mass-produced and a method of manufacturing the same.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the gist thereof is as follows. (1) Forging the external shape of each of the divided parts divided into a plurality of parts on an arbitrary surface in the axial direction of the transfer path, which is a metal precision machine part having a transfer path through which a liquid or a gas of a cylinder or a cylinder passes. Alternatively, a method of manufacturing a metal precision machine component in which a metal channel is formed by stamping, and then forming the conveying path through which the liquid or gas of the cylinder passes by at least one forging or pressing.

(2) The conveying path is stamped at 900 ° C.
The method for producing a metal precision mechanical part according to the above (1), wherein the method is performed at the above temperature. (3) The method for manufacturing a metal precision machine part according to the above (1), wherein after the transfer path is stamped and formed, a divided surface is ground. (4) The method for manufacturing a metal precision machine component according to (1), wherein the conveying path is processed by mechanical groove processing and laser groove processing.

(5) In the manufacturing method according to any one of the above (1) to (4), the divided parts are assembled and formed by liquid phase diffusion bonding in an oxidizing atmosphere. Manufacturing method. (6) A precision metal part made of metal obtained by assembling and forming divided parts manufactured by the manufacturing method according to any one of the above (1) to (5) by liquid phase diffusion bonding.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the drawings. Conventionally, as described above, a mechanical component having a complicated shape such as a fuel injection valve for an automobile is cut out from a massive steel ingot or subjected to hot forging, and then subjected to a finishing process, followed by a complex process. Groove processing was carried out by a drill in a complicated fuel supply passage. This grooving is a drilling process (grooving) in more than a dozen steps, and is a complicated fuel supply passage, a material of high hardness, etc., resulting in damage to the drill, poor product yield, and reduced processing time. It took considerable time. In the present invention, as described above,
By manufacturing the half-split parts, the above-mentioned problem can be solved. This will be described with reference to FIG.

First, FIG. 1 is a schematic external view of a divided part for a metal precision machine which is an object of the present invention (here, an assembly molding by liquid phase diffusion bonding of a fuel injection valve for an automobile will be described). FIG. 1A is a plan view thereof,
(B) is a side view thereof. As shown in FIG. 1, the external shape of the automotive fuel injection valve has a very complicated shape due to restrictions such as a space in which the parts can be accommodated, and thus cannot be formed by ordinary molding. for that reason,
Cr having a required thickness by forging to the shape shown in FIG.
A pair of divided parts as shown in FIG. 2 (a) are formed by forging on a middle plate of Mo steel, and unnecessary portions (hatched portions) are sequentially removed by cutting, and finally, a part shown in FIG. ) = FIG. 1 (a)
Is manufactured. Then, the flat surfaces of these divided parts are ground to finish them into smooth surfaces or surfaces having a certain degree of roughness.

[0011] The divided parts are finally integrated with their flat surfaces aligned. However, since the fuel injection valve for automobiles has a complicated fuel supply passage on its inner surface,
It is necessary to provide a pipe (groove) through which fuel passes as shown in FIG. The present inventors have performed the groove processing at least once or more, usually only once, on the divided surface at once, thereby forming a groove 2 having a complicated shape at once, thereby forming a groove by a conventional drilling method which involves over ten steps. The processing is omitted.

Next, as shown in FIG. 4, the above-mentioned divided parts are divided into 85 parts by using an alloy for liquid-phase diffusion bonding.
It is heated to a temperature of 0 ° C. or higher, liquid-phase diffusion bonded, integrated and finished into a product as a fuel injection valve for automobiles. The liquid phase diffusion bonding alloy used in the liquid phase diffusion bonding is desirably an amorphous alloy in which substantially 50% or more is amorphous, for example, Ni or Fe.
An amorphous alloy containing P, B, C, Si or the like as a diffusion element on a base is most suitable. Specifically, as shown in FIG. 4, the divided parts are butted together, and between these butted surfaces, an amorphous alloy having a thickness of about 30 μm, which is cut or machined into the same shape by cutting or machining. , And apply the necessary and sufficient stress for liquid phase diffusion bonding, put the entire part into an atmosphere-controllable furnace having a high-frequency induction heating coil, and quickly perform liquid phase diffusion bonding. Temperature, preferably at a temperature of 850 ° C. or higher, and maintained at the same temperature for the time necessary for isothermal solidification of liquid phase diffusion bonding, and thereafter, the entire part is cooled to room temperature to remove burrs, and as shown in FIG. The product is finished to the final outer shape. The processed shape of the foil may be a foil completely identical in shape to the joining surface, or may be an arbitrary shape including the joining surface, such as a substantially rectangular or substantially elliptical foil. In any case, there is no difference in the product properties after joining, and no difference is observed in the mechanical properties of the joint and the appearance after finishing.

[0013] The alloy foil for liquid phase diffusion bonding is single,
Alternatively, the same characteristics are obtained even when a plurality of sheets are stacked. It has been stated that it is desirable to heat the liquid phase diffusion bonding to a temperature of 900 ° C. or higher, but it is needless to say that there is an optimum temperature in relation to the melting point of the foil.
℃, 850 to 14 corresponding to various foils
The temperature can be selected up to 00 ° C, and it is necessary to heat to this temperature range. Further, the isothermal solidification process of the liquid phase diffusion bonding is a special solidification phenomenon caused by diffusion control of general diffusion atoms such as B, P, C, Si, etc., and B, P, C into the material to be bonded. Is a factor determined by the diffusion rate of Si, Si, etc., but the diffusion rate greatly changes depending on the joining temperature, and isothermal solidification is completed in a shorter time at a higher temperature. In addition, it is possible to appropriately select a time that is industrially feasible in the production of parts, and in the present invention, it is desirable that the time be set between 10 seconds and 600 seconds.

In performing the liquid phase diffusion bonding, N ₂ or Ar is blown onto the inner and outer surfaces of the material to be bonded in an oxidizing atmosphere containing 0.01% by mass or more of oxygen, preferably in the air. It is preferable to work. In the present invention, the example of Cr-Mo steel has been described as an automotive fuel injection valve, but the structure and material of the target mechanical part are not particularly limited, and liquid phase diffusion bonding can be applied. It is possible to use a metal material which is considered to be. For example, it is possible to realize a joining joint in liquid phase diffusion bonding even with materials that are normally difficult to weld, such as ordinary carbon steel, high carbon steel, and low carbon steel. Liquid phase diffusion bonding of stainless steel containing Cr and Ni, high corrosion resistance alloy steel, Ni-based alloy, and other non-ferrous materials such as Al, Ti, Zn, etc. by using a suitable bonding alloy. Becomes possible.

In the present invention, the above-mentioned grooving can be performed by ordinary machining, for example, grinding or laser processing, instead of forging, but it may be expensive in terms of cost. However, the forging described above is most preferable in terms of processing cost.

[0016]

EXAMPLE In this example, the manufacture of a fuel injection valve for an automobile will be described. Cr: 1.0%, Mo: 0.5%
First, as shown in the steps of FIGS. 2A to 2F, divided parts (in this embodiment, halved) from a 2.0 mm thick middle plate made of high carbon steel containing 2 is formed by forging, and m and m 'are cut off.
2 (b), n, n ′, FIG. 2 (c), o, o ′, FIG. 2 (d)
P, p 'of FIG. 2 and q, q' of FIG. 2E were cut off, respectively, to produce the divided parts 1 and 2 shown in FIG. Next, as shown in FIG. 2, a plurality of grooves (pipelines) were provided on the divided surface by one forging.

A thickness of 30 μm between these divided parts 1 and 2
The parts 1 and 2 are put together with a diffusion bonding alloy made of a Ni-based amorphous alloy containing small amounts of B and P, and the stress required for liquid phase diffusion bonding, that is, a plurality of upper and lower surfaces of the parts 1 and 2 The entire part is heated to a liquid-phase diffusion bonding temperature of 1150 ° C. in an atmosphere controllable furnace having a high-frequency induction heating coil, held at 300 ° C. for 300 seconds, and then the whole part is cooled to room temperature. To remove burrs,
Finished to the final outer shape as shown in FIG. 5, a product of an automotive fuel injection valve was obtained. When the automotive fuel injection valve manufactured in this way was used as an actual automobile part, the performance was exactly the same as that of a conventional fuel injection valve manufactured by drilling. , Abrasion resistance, and the joint surface strength with respect to the fluid pressure showed exactly the same value.

[0018]

As described above, the precision metal parts assembled and formed by liquid phase diffusion bonding according to the present invention can be rapidly processed in a simplified manufacturing process, and the manufacturing cost can be reduced. Have

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of the appearance of a divided component having a divided surface according to the present invention.

FIG. 2 is a view showing a processing step of a divided part having a divided surface according to the present invention.

FIG. 3 is a diagram showing an example in which a groove is formed by forging on a divided surface according to the present invention.

FIG. 4 is a diagram showing an example of a cross section of a divided part having a divided surface according to the present invention.

FIG. 5 is a view showing a part after finishing processing according to the present invention.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuhiro Shinohara 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division (72) Inventor Yutaka Takagi 4005 Nishi-Oguma, Ogumacho, Hashima-shi, Gifu Prefecture Fukuju F term in Industrial Co., Ltd. (reference) 4E067 AC03 BA05 DA13 DA17 DC06 EB00 4E087 AA10 CA11 CB01 DB02 DB22 DB24 HA00

Claims (6)

[Claims] 1. A metal precision machine component having a conveying path through which a liquid or a gas of a pipe or a cylinder passes, wherein each external shape of a divided part divided into a plurality of parts at an arbitrary surface in the axial direction of the conveying path. A method for manufacturing a precision metal part made of metal, in which, after being sequentially formed by forging or pressing, a conveying path through which a liquid or a gas of a cylinder passes is stamped and formed by at least one forging or pressing. 2. The method according to claim 1, wherein the conveying path is formed by stamping and molding at a temperature of 900 ° C. or higher. 3. The method according to claim 1, further comprising, after stamping and forming the transfer path, grinding the divided surface. 4. The method for manufacturing a metal precision machine part according to claim 1, wherein said conveying path is machined by machining a groove or a laser groove. 5. The method according to claim 1, wherein the divided parts are assembled and formed by liquid phase diffusion bonding in an oxidizing atmosphere. . 6. A precision metal part made by assembling and forming divided parts produced by the production method according to claim 1 by liquid phase diffusion bonding.