JPS5918461B2 - Red-bellied goldenrod - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method aimed at improving the corrosion resistance of rapidly solidified metal materials such as amorphous alloys and customizing materials such as 180° close bending.

For example, a rapidly solidified alloy (hereinafter simply referred to as an amorphous alloy) whose main component is Fe-P-C-Cr.

) has excellent strength, corrosion resistance, and 180° close bending notes.

It is necessary.

Nitrogen is particularly effective in improving corrosion resistance.

Note that the 180° close bending of the rapidly solidified metal material decreases depending on various factors, but particularly as the crystallization of the alloy progresses, it decreases significantly.

By the way, in order to produce an amorphous alloy, molten metal adjusted to a desired composition range is rapidly solidified at a rate of, for example, 106°C/sec. When nitrogen is added, it is added in the form of a nitrogen alloy. is normal.

The amount of nitrogen added to the amorphous alloy is considered to be approximately 0.3% (by weight) by analogy with the amount of nitrogen added to stainless steel.

However, as a result of various studies, the present inventors have confirmed that the amount of nitrogen required in the amorphous alloy is at most about 0.03% (by weight).

That is, it was confirmed that the conventional method of adding nitrogen alloys contains elements other than nitrogen in the alloy.

In addition, it is inferior in 180° close bending and ductility, which are important properties in amorphous alloys.

It was also confirmed that there were commercial problems such as high alloy costs.

The present invention was made based on such knowledge, and instead of using a nitrogen alloy as an amorphous alloy raw material, the raw material is melted and nitrided in a nitrogen atmosphere, and the molten metal is converted into a desired material. It is characterized by being rapidly solidified into the shape of

The nitrogen content of the alloy of the present invention is determined by melting the alloy using a melting furnace that can control the atmosphere and changing the nitrogen gas pressure in the atmosphere or the nitrogen partial pressure by mixing nitrogen and an inert gas. It can be controlled by melting.

Further, since the nitrogen-containing alloy melted by the method described above hardly changes in composition even after cooling, it is possible to remelt it as it is and use it as a raw material.

EXAMPLE An alloy having the components shown in Table 1 was melted using a 500g melting furnace.

At that time, for A1 to 3, chromium nitride was used in an argon gas atmosphere, for A4 and 5, the raw material was dissolved in a nitrogen gas atmosphere, and for A6, the raw material was dissolved in a mixed atmosphere of nitrogen and argon gas.
Ribbon-shaped amorphous alloys were manufactured by centrifugal quenching.

The obtained ribbon-shaped amorphous alloy had a thickness of 20 to 50 μm, a width of about 1 mm, and a length of about 300 mm.

Table 1 compares the characteristics of the product manufactured by the method of the present invention without using a nitrogen alloy and the product manufactured using a nitrogen alloy with nitrogen added to the alloy.

The corrosion resistance was 50% from the amorphous alloy produced by each method.
A sample of the dragon length was taken and the weight change was measured after immersing it in a 100° C. pentahydric sulfuric acid solution for 6 hours.

Corrosion resistance of 100 in the table indicates that there was no weight change at all.

Further, the obtained amorphous alloy thin piece was closely bent at 180° and the state of breakage was investigated.

180° close contact bending X marks indicate breakage, and O marks indicate good bendability without breakage.

* ; Weight loss rate in 5% H2SO4, 100°C x 6hr immersion test As is clear from this table, the amorphous alloy component using nitrogen alloy and adding nitrogen has less Si compared to the one made by the method of the present invention. many.

In addition, when using a nitrogen alloy, 180° close bending is poor even if the nitrogen content is about 0.013% (weight), but the amorphous alloy manufactured by the present invention has a nitrogen content of 0.03% (weight). Even though it contained nitrogen, 180° bending was good.

From these facts, it is considered that when a nitrogen alloy is used, the presence of crystalline undissolved nitride in Si or the nitrogen alloy reduces 180° bending.

As explained above, according to the present invention, it is possible to prevent elements other than the intended addition elements from being mixed in, and therefore the alloy composition can be accurately guaranteed, contributing to material stability. .

Furthermore, since no nitrogen alloy is used, steps such as weighing and charging can be omitted, and therefore manufacturing costs can be reduced, which has great effects.

Claims (1)

[Claims] 1 Fe without using nitrogen alloy as alloy raw material
- A method for producing a rapidly solidified metal material, which comprises melting a P-C-Cr-based raw material in a nitrogen atmosphere and rapidly solidifying the molten metal, which has been adjusted to a desired composition range, into a desired shape.