JPS5964701A - High-temp. rubber press - Google Patents

Abstract

PURPOSE:To contrive the shortening of a cycle time and uniform compression, by surrounding a body to be treated after being preheated outside with a cup- shaped body comprising an insulating material, and inserting it in the rubber die of a high pressure vessel. CONSTITUTION:A body 17 to be treated is preheated at about 1,000 deg.C and inserted under a condition surrounded with a cup-shaped body 21 comprising an insulaing material in the rubber dies 13, 14 of a high-pressure vessel 2. Under this surrounded condition, a powdery pressure medium 19 is supplied to the interiors of the rubber dies 13, 14, and then the cup-shaped body 21 is taken out of the rubber dies 13, 14. Thereafter, under the condition that the high-pressure vessel 2 is hermetically sealed, a liquid pressure medium is introduced through an inlet or outlet opening 15 into a space between the high-pressure vessel 2 and the rubber dies 13, 14 and supplied to a through hole 12, to compress the rubber dies 13, 14. Thus, the pressure medium 19 is compressed, and the body 17 to be treated is isotropically pressed through the rubber dies 13, 14 and the powdery pressure medium 19.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-temperature press method for pressure sintering of powder materials, removal of internal defects in cast products and sintered crystals, diffusion bonding, etc.

A hot isostatic pressing method is known as a JJn1 pressure method for pressure sintering of powder material ζ1, removal of internal defects in cast products and sintered crystals, diffusion bonding, etc.

Currently, in the hot isostatic processing method used industrially, inert gases such as argon and nitrogen, or air are used as pressure media, and these gas pressure media have a
Under gas pressure reaching gf/d, several hundred to two
Compression processing is carried out at temperatures as high as 1,000 degrees Celsius, and because it uses gas pressure, the object to be processed is evenly compressed to the inside, regardless of whether it is large or irregularly shaped.Coupled with the high temperature, It is extremely effective for true densification.

By the way, in this pressurization method, pressurization, depressurization, heating with a heater installed inside the high-pressure container, and temperature lowering are performed, and the object to be processed is removed after completely recovering the gas pressure medium from the high-pressure container. However, the cycle time was long, for example, 7 lids and 8 hours were required for one cycle, resulting in very poor productivity.

□ In order to shorten the cycle time, an attempt has been made to heat the object to be processed and cool it outside the high-pressure container, and to pressurize, depressurize, and cool the supplied gas pressure medium in the high-pressure container. There is.

However, this still requires a cycle time of about 1 hour.

Therefore, it is theoretically possible to increase the capacity of the compressor for the gas pressure medium or increase the number of compressors.

However, in reality, commercially available high-pressure compressors have a limited capacity, and it is not rational to increase the number of compressors to an extreme in terms of balance with the main equipment.

In order to dramatically shorten cycle time and increase productivity,
Method 1 of using powder as a pressure medium, pressurizing the powder pressure medium by ordinary press compression, and pressurizing the object to be processed through the powder
．． has been proposed, for example, in Japanese Patent Application Laid-Open No. 120499/1983.

In this conventional example, the object to be processed is preheated in a preheating furnace, but due to the friction of the powder IHJ and the friction between the high-pressure container and the powder, an imbalance in pressure distribution occurs in the pressure medium, and the object to be processed is heated evenly. It is difficult to pressurize and compress unidirectionally f and f4.

To solve this problem, Mokuinen used powder as the pressure medium and a regular dry rubber 7"less type with a rubber mold placed on the inner surface of the high-pressure container. Therefore, in the present invention, a rubber mold is arranged on the inner surface of a high-pressure container, and a liquid pressure medium is supplied between the high-pressure container and the rubber mold to compress the inside of the rubber mold. This is the so-called "Woper Breath" method in which the object to be treated is isotropically pressurized, and the object to be treated is heated in advance outside and is surrounded by a heat-insulating cup-shaped object in a high-pressure container.
A powder pressure medium is supplied into the rubber mold in the enclosed state, and then the tip-shaped object is taken out of the rubber mold, and then, with the high-pressure container sealed, the high-pressure container and the rubber mold are connected at I14.
] is characterized in that a liquid pressure medium is supplied to the object to be processed isotropically pressurized via a rubber mold and a powder pressure medium.

Hereinafter, embodiments of the wooden invention will be described with reference to the drawings.

Figure 1 shows a so-called dry rubber press that is used directly for wood invention, and shows it being compressed under pressure. ing.

The press frame (1) is made with a hinge t1q not shown! It is pivotable about the vertical axis, and the high-pressure container (2) can be relatively moved in and out of the space of the press frame (1) through the pivoting movement.

The high-pressure container (2) is cylindrical, and a top closer (3) is attached to the top side and a bottom closer (4) is attached to the bottom side, and the top closer (3) and bottom closer (4) are attached to the press frame. (1) Upper and lower inner end surfaces (IAX
IB).

The top closer (3) has a cylindrical outer plug (6) inserted into the high-pressure vessel (2) and fastened with bolts (5), and an inner plug (6) that is removably inserted into the outer nuclear plug (6). 7).

The bottom closer (4) has a cylindrical outer plug (9) inserted into the high-pressure vessel (2) and fastened with bolts (8), and an inner plug that is removably inserted into the outer nuclear plug (9). It consists of 00.

A cylindrical support (inserted into the sabot) [111] is fixed to the inner surface of the container by welding in this example, and the upper and lower edges of the support (111) are fixed to the inner surface of the high-pressure container (2) by welding. ]) has a large number of through holes 02 opening N' in the radial direction.

The inner circumferential surface of the boat IIJI has a thin rubber mold (19
A thick rubber mold 03α4) is provided around the periphery of the high-pressure container (2), and a rubber mold 03α4) is disposed on the inner surface of the high-pressure container (2).

Furthermore, an inlet/outlet 09 for a pressure medium made of liquid is formed in the high-pressure container (2), and on the water side, it is formed in the lower peripheral wall of the container (2) and communicates with each of the through holes O2 via a radial passage aG. It is communicated.

Furthermore, in Fig. 1, (171 is the object to be processed, which is a sabot made of alumina etc.) (181 is the object to be treated, and the inner plug (1 (j) of the bottom closer (4) is placed on .

In FIG. 1, a pressure medium such as alumina powder or BN powder is used, and 201 is a rubber plate, which is attached to the inner plug (7) of the top closer (3).

Accordingly, in the present invention, the object to be processed [171] is heated in advance to, for example, about 1000° C. by an external elematic furnace tube, and then inserted into the inside of the rubber mold Q3 (+41). From the standpoint of preventing thermal burnout of the rubber mold (1,1 It is inserted inside the mold (13 (141).

That is, in this embodiment, a pot-shaped object [21+] having a retaining part (21A) at the center of the top, and an object to be processed [171] heated externally in advance are placed in the inner plug 00 of the bottom closer (3).
In this state, the pulling rod (2) is inserted from below the high-pressure vessel (2), and after insertion, the pulling rod (2) is movable up and down.
The lower end of 21 is connected to the retaining part (21A).

As another embodiment, the tip-shaped object I21) with a pulling rod attached thereto is kept waiting in the high-pressure container (2), or
The object to be processed (1
Lower the inner plug Qd containing 71 into the high pressure container (2).
The object to be processed [171] is inserted into the waiting pot-shaped object 1211 and surrounded by the object 1211.

Moreover, when the tip-shaped object (21) is made to protrude downward, the object to be processed +171 is inserted into this object C711, the tip-shaped object (211) and the inner plug αO are synchronously arranged in the upper row, and the high-pressure container (2 ).

According to Isuwa's embodiment, in short, high pressure vessel (2)
Inside, the object to be processed (171) is surrounded by a cup-shaped object t21+ which serves as a heat insulator.

However, in the illustrated embodiment, the equipment can be configured more compactly in the height direction (because of the pulling rod), and handling is also advantageous.

In a state in which the mouth η of the object to be processed is surrounded by the tip-shaped object (21) in the high-pressure container (2), the powder feeder c! shown in FIG. 2 is placed. 3), a powder pressure medium such as alumina or BN is supplied into the high pressure container (21).

During this process, the rubber mold 03α4) is heat-shielded by a pot-shaped object (21) made of a heat insulating material.

After the supply of pressure medium +191 has progressed to a certain extent,
When the tip-shaped object (21) is gradually pulled up through the pulling rod, the pressure medium [191] is filled from the bottom, and if the powder supply is continued, the pressure medium [119] is filled as shown in Fig. 8. It will be filled up.

In this process, the object to be processed [171 is the tip-shaped object I21]
Or heat shielded with pressure medium + HIl, rubber mold Q, I
Q41 is not exposed to the heat of the object to be processed L171.

In particular, the pressure tlIL body [1! When alumina is used as It, the insulation effect is great.

Note that when the pressure medium [1!11 is insufficient, it is replenished by the feeder (231).

Pressure medium! 1. Filling and rubber mold of the pop-shaped object 03□
After taking out outside αa, the inner plug (7) of the top closer (3) is inserted and the upper and lower inner end surfaces (IA) (IB) of the press frame (1) are brought into contact with the upper and lower parts of the high-pressure container (2). Put the high pressure container (2) into a sealed state (
See Figure 1: ).

In this state, the liquid pressure medium is introduced from the inlet/outlet α9.
When it is supplied to the through hole a2, the rubber mold a3α4) is compressed, / , thereby p, the pressure medium U! ]) is compressed, and here the object to be processed [171 is pressurized in the same direction via the rubber mold o:+ (141 and the powder pressure medium (1!'1).

After pressure molding, the liquid pressure medium is decompressed and discharged to the outside of the container (2) through the inlet/outlet 09, and then the rubber mold 09
θ41 is restored to the inner wall side of the high-pressure container (2) by its elastic restoring force, and on the other hand, the pressure medium 11m is in a pressure-formed state, and for example, as shown in FIG.
19A) and the rubber mold (I4).

Therefore, after fully rotating the press frame (1), the fourth
As shown in the figure, the powder molding (19A) and the product (1
7A) from the container (2) through the inner plug 00 of the bottom closer (4), and after that, the molded product (19A
) is removed, crushed, transported, discharged, etc., and then non-linked.

In addition, when the processing pressure due to liquid pressure medium is low,
If a powder pressure medium [19] that is difficult to mold is used, the fifth
As shown in the figure, when the inner plug (7) of the top closer (3) is removed, the tip-shaped object c21) is lowered and the inner plug αυ of the bottom closer (4) is lowered, the pressure medium flows down as shown in the figure. Separately collected, also in this case rubber mold 0
The 90mm is not exposed to the heat of the object to be processed lI'71'.

Furthermore, low-grade steel is optimal for the object to be treated u71, but gas pressure X! J (which is subject to the isostatic pressurization method according to C) is applicable.

Examples, t H1 metal bending, pressure sintering of ceramic powder, manufactured products and 11. It is possible to remove internal defects in l'l'j products.

In addition, radioactive gold scrap waste, radioactive ceramic waste (
Bricks, concrete, incineration ash, ceramic filters, etc.) are also covered.

In the case of powder monthly or radioactive waste, fill it into capsules,
sealed and processed.

Next, examples will be given.

Approximately 80 micron powder of high velocity silver with an inner diameter of 60 gates and a height of 12
It was filled while tapping into a soft pot capsule with a diameter of 0 mm and a thickness of 177 m. The filling rate is about 60%.

To this, a lid having a degassing pipe with an inner diameter of 10 mm and a length of 500 mm was welded by T-welding.

Next, connect the degassing tube to the vacuum device i7 and heat it to about 800°C.
While the capsule was being heated, the inside of the capsule was vacuum degassed to 10' Torr through a degassing tube for about 1 hour, and in this state, the degassing tube was heated with a gas burner and pressed together to seal the capsule.

The sealed capsule thus produced was heated to 1100°C.
The mixture was charged into an EREMA furnace heated at 100°C, and heated for 2 hours.

The entire capsule (object to be processed) taken out from the Elema furnace was surrounded by a pot-shaped object made of heat insulating material with glass wool placed between 1-inch thick mild steel plates, and charged into a high-pressure container with an inner diameter of 200 mm. Immediately, a pressure medium made of alumina powder was filled between the rubber mold and the pot-like object.

After filling with the pressure medium, the pot-shaped object was pulled out, and the high-pressure container was replenished with powder pressure medium until it was full, and then the high-pressure container was sealed.

Then, the object to be processed was pressurized at 200 MPa for 5 minutes, and then the object was depressurized and taken out from the container.

Note that the pressure is 200 M after the object to be processed is loaded into the press.
It takes about 2 minutes to reach PalC, and after the start of decompression, the treated body (
Product) Hardened for about 2 minutes before being taken out.

That is, the time the object to be processed stayed in the rubber press was about 10 minutes.

The processing body is a temporarily sintered body of alumina powder, which is a pressure medium, and is thermally stabilized. Therefore, it was unnecessary to use a tip-like object to protect the rubber mold after it was taken out.

As a result of measuring the density of the treated body, it was found that the high speed steel was sufficiently densified and had true density.

The present invention is as follows, and the pressure medium is a solid, that is,
Since powder and pellets are used, the cycle time can be extremely short and productivity can be improved.

Incidentally, compared to the gas pressure medium, which requires a long gas compression and recovery time, the present invention, which uses a powder pressure medium, is advantageous.

The object to be processed can be compressed isotropically to achieve true density.

Incidentally, when uniaxially compressing a solid powder pressure medium, an imbalance in pressure distribution always occurs, but in the present invention, in which the powder pressure medium is supplied into a rubber mold and pressurized, isotropic compression is possible.

Although a rubber mold is used, heat damage to the rubber mold can be prevented because a powder pressure medium is used and the object to be processed is surrounded by a heat-insulating tip-like object.

Complete sealing of the object to be processed (capsule) is not required. Incidentally, in the case of a gas pressure medium, complete sealing of the capsule is essential, but this is not a problem in the present invention, which uses a powder pressure medium.

Furthermore, it is possible to process even slender objects, and since the powder pressure medium can be crushed and reused, it can be used repeatedly. Incidentally, in methods using castor oil, grease, etc., the pressure medium deteriorates after just one use.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a dry rubber press used directly in the present invention, showing it during pressurization, Figure 2 is a cross-sectional view of the powder press being supplied to a high-pressure container, and Figure 8 is a cross-sectional view of the dry rubber press being supplied. Figure 4 is a cross-sectional view after the treatment, and Figure 5e is a cross-sectional view showing an example of recovery when the pressure medium is not formed. (1)...Press frame, (2)...High pressure fi
vessel, (3i...Top closer, (4)...Bottom closer, (LI Q41...Rubber type, 09...Liquid pressure medium inlet/outlet, u71...Object to be processed, (1m...・
Pressure medium, 21)...Cop-shaped object.

Claims (1)

[Claims] 1. In the so-called Woper Press method, a rubber mold is placed on the inner surface of a high-pressure container, and a liquid pressure medium is supplied between the high-pressure container and the rubber mold to isotropically pressurize the object to be processed inside the rubber mold. In this process, the object to be processed, which has been previously heated externally, is surrounded by a pot-like object made of a heat insulating material in a high-pressure container, and a powder pressure medium is supplied into the rubber mold in a state where the core is surrounded. ,after that,
The tip-shaped object is taken out of the rubber mold, and then, with the high-pressure container sealed, a liquid pressure medium is supplied between the high-pressure container and the rubber mold, and the object to be processed is filled with the rubber mold and powder pressure medium. A high-temperature rubber press method characterized by applying pressure isotropically.