JPS62279902A - Method of molding complicate form article - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Detailed Description of the Invention Field of Industrial Application The present invention relates to a method for molding a complex-shaped product such as a turbine rotor, which has a complex three-dimensional shape, using a cold isostatic press. It is something.

Conventional technology Turbine rotors, turbine blades, etc. are used at high temperatures and are required to be lighter in weight.
tC, Si, N. Research is being conducted on molding using ceramics such as.

Currently, the method of molding these complex-shaped products is to mold them with high precision using injection molding, followed by a long degreasing process (usually over 72 hours) to remove the large amount of organic binder added for the molding process. ) and a method of producing a product through a main sintering process is known.

Problems to be Solved by the Invention With this molding method, air bubbles and cracks are likely to occur in the molded product during the degreasing process to remove a large amount of binder that accounts for approximately 50υo1% by volume, resulting in defective products. The probability of this is 60 to 80 degrees, which is quite low.

In addition, it is very difficult to manufacture large-sized products, and the strength and reliability are low.

Means and action for solving the problem A matrix of approximately the same shape as the complex-shaped product is exploded to produce inorganic powders such as ceramics and metals, organic powders such as flour and starch, or polymeric materials suitable as binders for these powders. A concave mold is made from the above-mentioned mother mold using a mixed powder with water added to it, and after filling this concave mold with raw material powder for the molded product, it is isostatically pressed using a cold isostatic press, and then the concave mold is disassembled. By removing the molded product, the degreasing process is simplified.
This makes it possible to omit the structure, reduce manufacturing costs, and improve high strength and reliability.

Example As shown in Figure 1 (a), a model with the same shape as the complex-shaped product to be molded is made from a low-melting point material that melts at a sufficiently low temperature, and a master mold is created! shall be.

The low melting point materials include waxes and PB.

Sn, Cd, Zn, Sb 1s or 2
These include low melting point alloys, resins such as polystyrene and polyethylene, sugar, ice, etc.

As shown in FIG. 1(b), a mother mold 1 is embedded in a rubber container 2 with a powder 3 interposed therebetween, and a cold isostatic press is applied to the mold 1.
Concave shape 4 by pressure molding at low pressure of 1 to 20 tons
make.

The powder 3 has a higher melting point than the material of the matrix, and
Metal powder that can easily obtain sufficient strength of the molded product even with a pressure as low as 0Yi, preferably a powder finer than 80 mesh, or plastics and metals or plastics and ceramics that provide the functions of a binder and lubricant, preferably plastics 2 It is a mixed powder of ~30 volumes, in other words, it is an inorganic powder such as ceramics or metal, an organic powder such as wheat flour or starch, or a mixed powder in which an appropriate amount of polymeric material and moisture are added as a binder.

In this case, if ice is used as the matrix material, it is desirable that the powder used for the concave mold, such as metal powder, ceramic powder, plastic, etc., be sufficiently cooled to a temperature equal to or lower than that of the matrix. .

As shown in FIG. 1(C), the concave shape 4 is taken out from the rubber container 2, and a hole 5 is machined in the concave shape 4 to facilitate the elution of the matrix material. The concave shape 4 is immersed in hot water and heated to a temperature at which the matrix 1 is sufficiently eluted, and the matrix material is eluted from the holes 5.

Note that the matrix material may be eluted by heating in a heating furnace.

As shown in FIG. 1(d), the cavity 6 of the obtained concave mold 4
A predetermined target powder raw material 7 is filled into the container, and the whole is rotated on a rotary table 8 for centrifugal filling.

The predetermined target powder raw material 7 is a ceramic powder or the like that satisfies the requirements of complex-shaped products to be molded, and may be uniformly filled by applying vibration instead of centrifugal filling.

Furthermore, when a resin material is used as the concave mold material, it is heated to about 500° C. under reduced pressure to remove, decompose, or alter the resin content, making it easier to unframe the concave mold in a later step.

As shown in FIG. 1(a), after filling the holes 5 of the concave mold 40 with the same material as the concave mold material and closing the holes, the mold is set in a rubber mold 9 for cold isostatic press molding, and then the cold isostatic press is performed. 0 again
．． 7-5, high-pressure molding at OtoV- pressure. The pressure at this time is preferably equal to or higher than the pressure during the high-pressure molding described above. - As shown in FIG. 5 ψ, the high-pressure molded product is taken out of the rubber mold 9, the concave material is removed by a thermal decomposition method or a chemical method, and the molded product 10 is obtained.

If a mixed powder of metal and resin or ceramics and resin is used as the concave wall material and calcined at approximately 500℃, the concave material will tend to self-collapse after the high-pressure molding described above, so the concave material can be removed by brushing. is easily removed.

In addition, a mixed powder of metal powder and resin was used as the concave material, and 3
When high-pressure molding is performed at a pressure of 000V or more, the self-disintegration of the concave shape is not sufficient, so it is considered that the mechanically bonded parts of the metal particles are dissolved by immersing them in a solution such as acid or alkali that easily dissolves the metal powder. Framing can be done effectively〇Also, when organic powder such as wheat or starch is used as a concave material, it can be directly heated in a furnace to dehydrate and partially carbonize, then removed and broken. Good, in addition, water-soluble chlorides such as NaCL and Na nitrate
When using a mixed powder of 1VO and resin as a concave material, the resin content is removed in the step shown in Figure 1(d).
It is preferable to lower the temperature or omit heating for decomposition and alteration, and to dissolve the concave mold in water after the molding step shown in FIG. 1 (-) to break the frame.

As shown in FIG. 1 (!I), after forming the folding frame, the molded body 10 is machined as it is, or is machined after calcination, and is sufficiently sintered at a desired temperature.

As a specific example, a mother mold is made from wax, a mixed powder of PJ (250 mesh) powder and 10 volumes of nylon powder is used as the material for the concave mold, and the concave mold is formed by cold isostatic pressing at a pressure of 100 OV. As a result, it was confirmed that the concave surface roughness was very smooth and good, and since it was molded from the surrounding area using isostatic pressure, there was no deviation at all.

Also, Sz O! for concave wood! + When a turbine rotor was molded using phenol resin and tOs as a material, it was confirmed that it had excellent self-disintegration properties.

Effects of the Invention The present invention provides a method for molding complex-shaped products that simplifies the degreasing process, reduces manufacturing costs, and improves cavity strength and reliability.

[Brief explanation of the drawing]

FIG. 1<a>-0) is an explanatory diagram showing an embodiment of the method of the present invention in the order of steps.

Claims (1)

[Claims] 1. A matrix having approximately the same shape as the complex-shaped product is prepared, and inorganic powder such as ceramics or metal, organic powder such as wheat flour or starch, or an appropriate polymeric material or moisture as a binder thereof is prepared. A concave mold is formed from the mother mold using the added mixed powder, and after filling this concave mold with a bed of raw material powder for the molded product, isostatic pressure molding is performed using a cold isostatic press, and then the concave mold is disassembled. A molding method for complex-shaped products in which the molded product is taken out by 2. The complex shape as set forth in claim 1, wherein the periphery of the concave mold is sealed with a container, frame, or tape made of a material that undergoes significant elastic deformation when isostatically press molded using a cold isostatic press. How to mold the product. 3. A method for molding a complex-shaped product according to claim 1, wherein the matrix is made of a low-melting point material if the matrix cannot be demolded during concave molding.