JPH01222002A - Manufacture of intermetallic compound powder - 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 [Field of Industrial Application] The present invention relates to a method for producing powders of intermetallic compounds such as Ni At and Ti kl.

[Conventional technology]

Ni Aj, Ti AjSNiA4, TiA4SMo
Intermetallic compounds such as Si 2 and 0uAlzn are industrially produced as ingots by casting.

On the other hand, although there is an increasing demand for powders of these intermetallic compounds as raw materials for powder metallurgy for manufacturing structural materials, the manufacturing method has not yet been established.

Currently being attempted to produce intermetallic compound powders include:
In addition to the method of mechanically pulverizing the melted ingot, there are other conventional metal powder manufacturing methods such as the gas atomization method, the rotating electrode method, and the plasma rotating electrode method.

[Problem to be solved by the invention]

Among these methods for producing intermetallic compound powders, the method of mechanically pulverizing the molten ingots tends to introduce impurities such as oxygen and nitrogen during the pulverization process, making it difficult to obtain powder with the desired composition. Metals are melted at high temperatures for manufacturing purposes, such as N1
There was a drawback that the vapor pressure of a low melting point metal such as Al increases during the melting of a high melting point metal such as Al and T1, and the composition deviates from the target composition by the amount of vaporization. Even in the gas atomization method G, it was difficult to obtain powder with the desired composition because low melting point metals such as A4 were vaporized while the metal mixed with the desired composition was being melted. In addition, in the rotating N-pole method and the plasma rotating electrode method, the bar material used for the rotating electrode is manufactured by casting, which also has the drawback that low-melting point metals such as Al vaporize, making it difficult to obtain powder with the desired composition. .

An object of the present invention is to provide a method for producing intermetallic compound powder having a target composition without vaporization of low melting point metals or contamination of impurities.

[Means for Solving the Problems] In order to achieve the above object, in the method for producing intermetallic compound powder of the present invention, two or more types of fine metal wires with a diameter of 5 mm or less are bundled in a weight ratio of a target composition, and 101 in diameter
+t+11 or more composite bar, and this composite bar is heated at 1000 rpm around its axis in an inert gas atmosphere.
While rotating in the above manner, one end of the composite bar is heated and melted by irradiation with an electron beam, or melted by arc heat generated by arc discharge between the one end and the opposing electrode, and is scattered as particles.

The composite bar material only needs to be made of bundled thin metal wires that are integrated to the extent that they can withstand high-speed rotation, and can be integrated by, for example, hot isostatic pressing, extrusion, wire drawing, or rolling. The temperature during this integration is preferably 275 or higher than the melting point of the metal with the lowest melting point among the bundled thin metal wires; below this temperature, solidification may be insufficient and it may not be possible to withstand high-speed rotation. be.

[Effect]

In the method of the present invention, the composite bar material is simultaneously melted and scattered by rotational force, so that the molten metals such as N1 and )1 instantaneously diffuse into each other, become granular, cooled, and solidified. Therefore, the time during which the metal is in a molten state is extremely short compared to conventional methods, and therefore it is possible to prevent low melting point metals such as A1 from vaporizing. In addition, since the composite rod itself is made by integrating thin metal wires, there is no vaporization of low melting point metals during melting.

Contamination with impurities is also prevented.

The reason why the rotation speed of the composite rod is set to 1000 rpm or more is that if the rotation speed is less than 1000 rpm, the diffusion of each metal will be insufficient and a uniform composition will not be obtained. Also, this rotation speed is 110
If it exceeds 0,000 rp, it is not preferable because it is difficult to use the device for a long period of time due to its functionality and there are problems in terms of maintenance.

The reason why the composite rod is melted and scattered in an inert gas atmosphere is to avoid oxidation of the intermetallic compound particles in a molten state and at the same time promote cooling.

Therefore, in order to enhance these effects, the inert gas atmosphere preferably has a temperature of 30 Ill' or less and a pressure of 0.1 atmosphere or more.

If the diameter of the thin metal wire is larger than 5 fins, the diffusion and mixing of the molten metals will be poor and uniformity will not be obtained.

If the diameter of the composite rod is less than 1Q mm, diffusion and mixing of each metal will be poor, and the amount of deformation during high-speed rotation will be large.

〔Example〕

Example 1 So-called T1 thin wire with a diameter of 3 m and a length of 2000 mm (purity 99.9%)
) and At thin wires (purity 99.9%) of the same diameter and length were arranged in a random positional relationship at a weight ratio of 3:1, and vacuum sealed in a T1 can with a wall thickness of 4 mm. 980t
H-P treatment was carried out under the conditions of 1:' x 1200 x 2 hours.

Using the obtained cylindrical material, scrape off a portion of one can to make a diameter of 33w.
5 to form a composite rod of Ti and Al having a length of 19001111 mm.

The other end of this composite rod was fixed to a rotating device, and a W electrode was installed opposite to one end. The composite rod was heated at 16,000 r around its axis in a He gas atmosphere of 2 atm at 2C.
While rotating at pm, arc discharge was performed at 50 OA between one end of the composite bar and the W electrode. One end of the rotating composite rod was melted and scattered by the arc heat, yielding powder.

As a result of analysis, it was confirmed that the composition of the obtained powder was TiAt, and the particle size of the powder was 20 to 200 μm.

Example 2 N1 fine wire with diameter 3 and length 2000 mm (purity 99.1%)
) and A4 thin wire (purity 99.9%) of the same diameter and length were arranged in a random positional relationship so that the weight ratio was 3:1, and vacuum sealed in an N1 can with a wall thickness of 5 mm. One of the two samples created in this way was extruded at 1100 C (extrusion ratio 4), and the others were rolled and wire drawn at the same temperature.
Scrape off the N1 can part and make each part with a diameter of 30mm and a length of 2000mm.
A composite bar of fill N1 and A4 was formed.

The other ends of these composite bars were fixed to a rotating device, and 1
While rotating the composite rod at 20,000 rpm around its axis in a He gas atmosphere at atmospheric pressure, a
An electron beam was irradiated at A. One end of the rotating composite rod was heated by an electron beam, causing it to scatter while melting to obtain powder.

As a result of analysis, it was confirmed that the composition of the obtained powder was Ni3A4 and the particle size of the powder was 10 to 190 μm.

〔Effect of the invention〕

According to the present invention, an intermetallic compound powder having a target composition can be produced.

Applicant: Sumitomo Electric Industries, Ltd. , -1-

Claims (3)

[Claims] (1) Two or more types of thin metal wires with a diameter of 5 mm or less are bundled in a weight ratio of the desired composition, and are unified to form a composite bar with a diameter of 10 mm or more, and this composite bar is placed in an inert gas atmosphere with its axis centered. While rotating at 1000 rpm or more,
An intermetallic compound powder characterized in that one end of the composite rod is heated and melted by irradiation with an electron beam, or melted by arc heat generated by arc discharge between the one end and an opposing electrode, and then scattered as particles. manufacturing method. (2) The bundle of thin metal wires is
2. The method for producing an intermetallic compound powder according to claim 1, wherein the powder is integrated by hot isostatic pressing, extrusion, wire drawing, or rolling at a temperature of /5 or higher. (3) The temperature of the inert gas atmosphere is 30℃ or less and 0.1
The method for producing intermetallic compound powder according to claim 1, wherein the pressure is at least atmospheric pressure.