JPS6312969Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a core of an extrusion molding machine using a hollow die, and more specifically, the core of the hollow die is made of an amorphous metal and has a diameter of 200 μm or less. The present invention relates to a core of a characteristic extrusion molding machine.

Conventionally, various mechanisms have been considered as extrusion molding machines for producing hollow materials, and a method using a core is known as one of them. As shown in Fig. 1, the structure is as shown in Fig. 1.
is attached, and the die body 2 is composed of an arm 4 that fixes the core 3 to the die body 2 and a cap 5. The molding material 6 fed from the extrusion molding machine 1 to the die body 2 is After being cut once, it is extruded from the cap 5 while covering the core 3,
A hollow continuous molded product is created. At this time, the core 3 is worn by the molding material 6 and is subjected to stress such as tension and twisting, so the core 3 is generally hard and has excellent wear resistance.
Moreover, a wire rod with high bending strength and tensile strength is required, and the better the above-mentioned characteristics are, the more stable and accurate the hollow molded product can be obtained. For this reason, hard and strong metal wires such as cemented carbide, piano wire, tungsten wire, and stainless steel wire have conventionally been used as materials for the core.

However, for cores with diameters of 200 μm or less, the above-mentioned wires still cannot provide sufficient properties, and the following problems arise.

(1) When extruding materials with high abrasive force such as ceramics, the metal itself is easily worn out, making it difficult to obtain hollow molded bodies with stable precision.

(2) When extruding the molding material, a considerable amount of force is applied to the metal wire that is the core, so the core is likely to be torn off.

(3) If piano wire, iron wire, etc. are used for the core, their corrosion resistance is poor and the surface of the core is likely to corrode, resulting in rust and partial deterioration. Rust is unfavorable in terms of core accuracy, and partial deterioration can lead to core tearing during extrusion.

As mentioned above, when conventional metal wires are used as cores having a diameter of 200 μm or less, problems such as tearing of the wires, abrasion, and rust occur, which reduces productivity and deteriorates the inner surface quality of the holes. This tendency was particularly strong when a material with a large frictional force was used as the molding material.

The inventor of the present invention focused on the fact that the various problems mentioned above are caused by the internal structure of the metal itself, and as a result of intensive study, by using an amorphous metal as the material for the core with a diameter of 200 μm or less, It was discovered that a good hollow molded body could be obtained.

That is, the amorphous metal used in the present invention is
Transition metals such as Fe, Ni, Cr and Si, P, C, B
It is an amorphous metal obtained by ultra-quenching of a raw material melt, vacuum evaporation, sputtering, plating, ion plating, etc. using nonmetals such as raw materials, and its structure is a three-dimensional long-period regular particle arrangement. It has an amorphous crystal structure with no crystal structure, and does not contain the various disturbances and defects (grain boundaries, dislocations, etc.) found in ordinary metals, which have a regular crystal structure, so it has excellent mechanical strength. It has various superior characteristics compared to conventional metals, such as extremely large diameter, high wear resistance, excellent corrosion resistance, and appropriate elasticity.

By using an amorphous metal for the core of the present invention, there are excellent advantages not found in the past, as described below. That is, (1) Even when extruding materials with a high abrasive force such as ceramics, the abrasion resistance is high, so a hollow molded body with stable precision with little variation can be obtained.

(2) The bending strength and tensile strength of amorphous metals are several tens of times higher than that of conventional cemented carbide or iron wires, so even if the diameter is less than 200 μm, it is difficult to prevent them from tearing during extrusion. I can do it.

(3) Since it is strong, the length of the core can be adjusted sufficiently. In other words, since the distance between the arm and the cap can be adjusted arbitrarily, the molding material cut by the arm is extruded from the cap after being sufficiently joined, so there is no worry of cracks or cracks occurring in the hollow molded product. .

(4) Since the length of the core can be adjusted, it also has the following major features.

In other words, when a molded body is extruded, the rapid release of pressure after extrusion causes the molded body to bulge, shrink, twist, etc., and is usually fixed in that form. be. Therefore, even in extrusion using a core, it is not possible to adjust the length of the core due to the strength of conventional metals, so changes in the molded product after extrusion inevitably affect the inner surface properties of the pores, leading to variations in pore diameter. This results in distortion, twisting, etc. However, when amorphous metal is used, the core can be adjusted to a longer length.
Even if a minute change occurs in the molded product after extrusion, it is extruded and fixed with the pore shape memorized by the core, resulting in an excellent inner surface with little variation such as fluctuation or twisting even with an extremely small pore diameter. A hollow molded body having a shape can be obtained.

(5) Since it has high strength and elasticity, it is possible to suppress the shaking of the core during extrusion as much as possible, so a stable hollow molded product can be obtained.

(6) Excellent corrosion resistance, so there is no need to worry about rust or partial deterioration.

(7) It has high wear resistance, so it can be used for a long time. Therefore, it is not necessary to replace the die in a complicated manner, which is extremely productive.

The amorphous metals used as the core of this invention include transition metals such as Fe, Cr, Ni, and Co, as well as Si, P,
Examples include non-metals such as C and B, or amorphous metal compounds, and these may be used alone or in combination. Alternatively, an amorphous metal may be deposited around an ordinary metal wire such as stainless steel or tungsten wire by sputtering or the like.

The shape of the core may be linear, ribbon-like, etc., the diameter thereof is 200 μm or less, and the cross-sectional shape may be circular, triangular, quadrangular, etc.

The core of the present invention can be applied not only to extrusion molding using a hollow die, but also to other hollow molding methods, such as the crosshead method and the slurry method.

Next, an example of the present invention will be described.

Example 1 A core was made of an amorphous alloy of Fe and Ni with a wire diameter of 50 μm obtained by ultra-quenching a raw material melt. As a molding material, we used alumina with a caking agent added, and as a result of continuous extrusion molding with an outer diameter of 2φ, we were able to obtain an extremely stable alumina hollow molded body with continuous pores of 50 μm in diameter. The amorphous alloy core was not torn or corroded.

Example 2 Sputtering on tungsten wire
The core was an amorphous alloy with a wire diameter of 150 μm on which Ni and Cr were precipitated. As a molding material, tungsten
Using carbide with a binder added, the outer diameter
As a result of extrusion molding at 0.6φ, a hollow molded tungsten carbide thin-walled pipe with a stable pore diameter of 150 μm and no cracks or cracks was obtained.

Example 3 A ribbon-shaped amorphous alloy consisting of Fe, Si, and B obtained by ultra-quenching a raw material melt was used as a core. Using polycarbonate and carbon fiber powder or polycarbonate and glass fiber powder as the molding material, extrusion molding was performed with an outer diameter of 1φ, and as a result, a very good continuous hollow molded body was obtained.

As described above, when an amorphous metal is used for the core, the amorphous metal itself has excellent wear resistance, strength, and corrosion resistance, so the resulting hollow molded product has little variation in hollow pore diameter. It has various excellent effects, such as being extremely stable, less prone to wear and tearing, and being able to be used for a long period of time, making it more productive.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an extrusion molding machine using a hollow die. 1... Extruder, 2... Die body, 3... Core,
4... Arm, 5... Base, 6... Molding material.

Claims (1)

[Scope of utility model registration request] In the core of an extrusion molding machine using a hollow die,
The material of the core is an amorphous metal, and its diameter is
A core for an extrusion molding machine characterized by having a diameter of 200 μm or less.