JPS5950951A - Production of tube mold - Google Patents

Abstract

PURPOSE:To produce a tube mold for continuous casting by winding a wire or belt material made of metal for the mold on the outside of a core having the same shape as the inside surface shape of the mold for continuous casting, enclosing the outside thereof with a case, evacuating the spacing between the core and the case to a vacuum state and subjecting both to hot pressurization. CONSTITUTION:A wire- or belt-like material 2 consisting of a copper alloy for a small sized tube mold for continuous casting is wound on the outside of a refractory core 1 having the same outside diameter as the inside space shape of the tube mold. The core is sealed in a case 3 made of metal or glass and the inside of the case is evacuated. Alternatively, metallic powder 4 for the mold is packed in the spacing between the core 1 and the case 3, and after the inside of the case is evacuated, the case 3 is charged into a hot isotropic pressurization furnace, wherein the case is pressurized at a high temp. from the entire outside circumference of the case by gas such as nitrogen to weld and sinter the wire- or belt-like material or the powder material to the outside surface of the core 1. The core is removed and the tube mold is manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a tube mold used for manufacturing a relatively small casting 11 in a continuous defense mold.

This type of tube mold is, for example, a straight tube shape in which the inner diameter gradually decreases from the top to the bottom Z as shown in Figure 1, or a straight tube whose inner diameter gradually decreases from the top to the bottom as shown in Figure 2. The inner diameter gradually decreases, and the overall shape is slightly curved. The inner surface of the mold body (1'), which is usually made of copper or prepared alloy, is coated with a wear-resistant coating (2') of nickel or its alloy.
) is used in the form attached.

This tube mold generally has a small inner diameter but a large length in the vertical direction, and it is even more difficult to polish the inner surface of the curved tube mold. However, since the inner diameter of the tube mill requires strict cutting dimensions, the current situation is that good finishing is being achieved with many difficulties.

The present invention aims to provide a method for manufacturing a mold using a tube having an accurate and smooth inner surface without the above-mentioned difficulties. After wrapping a linear or band-shaped key around the outer periphery of the core that matches the desired shape of the inner space of the tube mold, the whole is made airtight with a nose made of a suitable element key such as metal or glass. At the same time, the inside of the case is degassed to create a vacuum state, and then the IJz marked line or strip material is closely attached to the outer surface of the core during hot isostatic pressure treatment.
This is a manufacturing method for tubes characterized by removing the core after diffusion bonding in a state, and in this case, powder material may be used instead of a linear or strip material. After placing the core in the chamber, the powder material is filled.

The present invention will be described in detail with reference to the drawings. First, a core (1) as shown in FIG. 3 is prepared. This core (1) is made of ceramic such as alumina or other heat-resistant material, and may be assembled from a plurality of divided pieces as long as the outer shape can be maintained. In the case of +c, the outer shape is made to match the desired internal space shape of the tube ball, but in this case, since the outside is to be machined, the machining is easy (and the machining accuracy is sufficiently accurate). It is possible to do this.

A linear or band-shaped material (2
) is wrapped (see FIG. 4), then sealed in an airtight case made of a suitable material such as metal or glass, and the inside of the case is evacuated (see FIG. 5). Also, arrange the airtight case (3) as shown in Figure 6, and connect the core (1) and the case (
3) Fill the space between the powder material (4) and the inside of the case to create a vacuum.

After that, the entire case is charged into a hot isostatic pressure treatment furnace, and the Rl
A treatment in which high pressure is applied from the entire circumference of the case using a suitable gas for operation such as nitrogen gas or argon gas, that is, a hot isostatic pressurization treatment is performed at JR Castle.

The conditions for the hot isostatic pressure treatment (B) vary depending on the size of the object, linear, strip, or powder material type, but it is usually maintained at 500 to 1000°C and 100 to 400 atm for 1 to 5 hours. .

By applying such hot isostatic pressure treatment, the linear or band-shaped material or powder material wrapped around or filled around the core is pressurized from its entire circumference, and is applied to the outer circumference of the core. They are plastically deformed into a form that completely adheres, and are then integrally joined or sintered, after which the case is removed and the core is removed.

- A bumold is obtained.

Regarding the linear or 41F-shaped shrine or powdered lumber 4 used here, since these key materials are used as materials for the tube mold, 1. Usually copper or copper alloy is used in consideration of the cooling performance, but the core material is made of copper or copper alloy. If you use nickel or nickel alloy, which is highly heat-resistant and wear-resistant, only in the closest part, and copper or copper alloy on the outside, it is possible to transfer the tube mold whose inner wall surface is coated with a heat-resistant and wear-resistant layer. I can do it.

As for the method of filling the powder material, in addition to using the powder material as it is, there are also cases where it is used in the form of a suitable slurry, and there are also cases where it is used together with a linear or band-shaped material, that is, the fifth method.
As shown in the figure, powder material * is used in the space that remains inside the case after the wire or band-shaped material is wrapped around it and stored inside the case.
It is sometimes used in a state where it is filled with 1.

As described above, according to the method of the present invention, as long as a core with the same external shape as the internal space shape of the required duplex mold is prepared, the member to be made into the tube mold can be used in the form of a line, band, or powder. Therefore, it can be easily blended onto the outer surface of the core, and can be completely adhered to the core by subsequent heat isostatic pressure treatment. Since the processing of the core involves processing the outer surface, it is much easier and more accurate than processing the inner wall surface of a tube mold, and the core can be used over and over again, making mass production easier. is large.

Furthermore, in the method of the present invention, only the inner side (the side near the core) of the linear, band-shaped, or powder material used is made of a heat-resistant and wear-resistant material, so that a coating layer with these properties can be applied to the inner wall surface of the tube mold. It is possible to manufacture the same coating layer at once, and the material for the coating layer can be selected from a wide range of materials.In other words, it can be used for composite materials such as metal and ceramic materials that are difficult to coat with the usual metal coating method or thermal spraying method. It's a bastard.

[Brief explanation of drawings]

FIGS. 1 and 2 are perspective views showing a general form of a tube mold, FIG. 3 is a perspective view of a core used in the present invention, and FIGS. An explanatory diagram showing the process. In the diagram, (1): Core (2); Linear or IIFI-shaped (3): Airtight case Patent applicant Kuroki Kogyo Co., Ltd. Representative Director Ariyoshi Kyoiku No. 1L 1
Figure 2 Figure 5 Figure 6

Claims (1)

[Claims] 1. After wrapping a linear or band-like material around the outer periphery of the core, which is made of #4 thermal material and whose outer shape matches the desired shape of the internal space of the mold. The whole is covered with a case made of a suitable material such as metal or glass to make it as airtight as possible, and the inside of the case is evacuated to create a vacuum state, and then subjected to heat isostatic pressure treatment.'' Alternatively, a method for producing a tube mold, which comprises the steps of diffusion bonding the strip material in close contact with the outer surface of the core, and then removing the core. 2. A core made of heat-resistant material whose outer shape matches the desired internal space shape of the duplex mold is made of metal,
After disposing the core in a case made of a suitable material such as glass so that the distance between the outer circumference of the core and the inner wall of the case is approximately equal throughout the circumference, filling the space between the outer circumference of the core and the inner wall of the case with a powder material, Next, the case described in Part 2 was sealed as airtight as possible, and the inside of the case was degassed to create a vacuum state. After that, the vacuum state was created by hot isostatic pressure treatment, and then by hot isostatic pressure treatment. A method for producing a duplex mold, characterized in that the core is not removed after the powder material is diffusion bonded in close contact with the outer surface of the core.