JPS62214105A - Production of ni-base spherical amorphous metal grain - Google Patents

Abstract

PURPOSE:To make mass production of Ni-base spherical amorphous metal grains of large grain sizes which are extremely industrially advantageous by continuously pouring a specifically composed Ni alloy from a molten state into cooling water which is kept rotated in a specified direction by a stirrer. CONSTITUTION:The melt of the alloy consisting, by atom%, 12-25% P, 0.1-76% >=1 kinds among platinum group elements Pd, Pt, Ir, Rh, Ru, and Os and the balance Ni is filled into a furnace body 1. A nozzle 2 is attached to the base of the furnace body 1 and the molten metal is pressurized by gase ous Ar from the top surface. A cooling tank 3 contains the cooling water which is kept stirred by the stirrer 4 so as to rotate at a prescribed flow rate. A stopper of the nozzle 2 is opened in this state to pour the molten metal into the cooling water at a prescribed gushing flow rate. The Ni-base spherical amorphous metal grains are easily produced in a large quantity by the above- mentioned method. The resulted metal grains have good sphericity, large grain sizes and grain size distribution of small variance are thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing Ni-based spherical amorphous metal particles.

[Prior art and its problems]

Conventionally, Ni has excellent corrosion resistance, oxidation resistance, high temperature properties, etc., and has been widely used in everything from general structural materials to special structural materials, aircraft materials, missiles, etc.

It is also widely used as a variety of magnetic materials due to its properties, and is also widely used as a catalyst material.
It is an extremely important metal element industrially. Moreover, using an alloy with a composition containing Ni, alloys having an amorphous state by liquid quenching can be produced by Ni-P, N1-B, N1-P-B%.
Ni-8i-B, N1-Pd-P, Ni-Pd-8
i%N1-Pt-P% Ni-Pt-8i, N1-Cr
-P, Ni-Mo-C, N1Al-B, Ni-Zr, N
It is obtained from alloy systems such as i-Hf and Ni-Nb, and most of the samples in these cases have a thickness of 10 to 10 mm.
The thin strip was about 30 μm, and among the liquid quenching methods, the one-roll method, piston anvil method, etc., which were the easiest to prepare the sample, were used.

On the other hand, recently, industrially extremely useful amorphous thin wire materials have been produced at low cost using an ultra-high-speed direct production method, and furthermore, the rotating liquid spinning method (Japanese Patent Application Laid-open No. 56-165016), and Ni-Pd Si, N1-P
The circularity of the cross section is 90% or more due to the d-P alloy system,
High-quality thin metal wires having a very uniform shape with wire diameter unevenness of 4% or less are continuously produced. (Unexamined Japanese Patent Publication No. 60-5
(Refer to Publication No. 9032) However, the ribbon-shaped materials and thin wire-shaped materials obtained in this way have restrictions on their uses due to their shape, and are difficult to process into bulk materials. Processing into metal grains is also difficult.

In addition, methods for obtaining amorphous spherical metal particles include dropping molten metal into cooling water, dividing the molten metal using a filter, mesh, rotating plate, jet stream, etc., and cooling it in the liquid. , molten metal is divided into spheres by using a net or rotating plate placed in cooling water. Furthermore, it has been obtained by the atomization method, the disk quenching method, the rotating liquid injection method, and the like.

However, the method of dropping molten metal into cooling water has poor mass productivity, and other methods have drawbacks such as being mechanically complex. The particles obtained by these methods have small particle sizes and are almost powder-like, and large particle sizes have not been obtained.

[Purpose of the invention]

In view of these circumstances, it is an object of the present invention to provide a method for producing industrially extremely useful large-diameter Ni-based non-spherical amorphous metal particles easily and with good mass productivity.

[Structure of the invention]

The present inventors have discovered that when a Ni-based alloy with a specific composition is continuously injected from a molten state into cooling water that is rotated in a fixed direction by a stirrer, the particle size is large and the sphericity is high. It was discovered that Ni-based non-spherical amorphous metal particles with small variations in diameter distribution can be obtained with good mass productivity, and the present invention was completed.

That is, the composition range is 12 to 25 atomic percent of P, 0.1 to 76 atomic percent of one or more of the platinum group elements Pd, Pt, Ir, Rh, Ru, and Os, and the balance is substantially Ni. It consists of an alloy of In addition, in these compositions 1, for example, the nozzle diameter is about 0.06 to 2.0III11, the flow rate of the molten metal is about 3 to 22 m/s, and the flow rate of the cooling water is 0.
．． By continuously injecting the molten metal into cooling water rotating in a fixed direction by a stirrer under conditions of 0.01 to about 22 m/s, the particle size is reduced to about 0.06 to 2.0 III11.
Spherical amorphous metal particles with high sphericity are obtained.

In particular, in order to obtain spherical amorphous metal particles with high sphericity and small variation in particle size distribution, it is desirable that the shape of the nozzle hole be circular or polygonal, and in the case of an ellipse, the ratio of the major axis to the minor axis It is necessary that the value is within about 2=1, and when it becomes about 3=2 or more, the sphericity decreases. The same applies to flat nozzles. Further, it is desirable that the flow rate of the cooling water be equal to or lower than the flow rate of the molten metal injected from the nozzle. The continuity of the molten metal flow is affected by the nozzle diameter and the flow rate of the molten metal, but it is at least about 0.5
It is desired that the length is G or more.

If the length of the molten metal flow is less than about 0.5G, the variation in particle size distribution will increase, which is not preferable. Furthermore, the angle between the molten metal flow injected from the nozzle and the cooling water surface is 15
degree or more is preferable.

In this way, since it is only necessary to continuously inject the molten metal into the cooling water, it is possible to manufacture the molten metal easily and in large quantities.

Next, the reason for limiting the composition range will be explained. As mentioned above, the content of P needs to be 12 to 25 atomic %, and more preferably 16 to 22 atomic %. When the amount of P is outside the range of 12 to 25 at %, the ability to form an amorphous state is significantly reduced. In addition, it is necessary that the platinum group elements such as Pd and pt be in an amount of 0.1 to 76%, more preferably 12 to 7%. If this amount exceeds 7%, it becomes amorphous. Although it is in a good quality state, it becomes difficult to form into spherical shapes, and its sphericity and hardness decrease. On the other hand, if the content is less than 12 at %, the ability to form an amorphous state is significantly reduced. The remainder consists essentially of Ni, but may contain impurities to the extent that they exist in ordinary industrial materials.Furthermore, in order to improve mechanical properties, W', Go, Cr, etc. %Fe,
Mn, V, NblMo, Ti.

It does not prevent the addition of Ta or the like or the dispersion of WC, TiC, etc.

The spherical particles obtained according to the present invention have very good sphericity, and have a sphericity of at least 95% or more.

These spherical particles can be subjected to continuous cold working, and in order to further improve dimensional accuracy and mechanical properties, they can be subjected to processing such as lapping, and if necessary, heat treatment such as annealing. can also be done.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples 6. The furnace body 1 is filled with molten metals of alloys having various compositions shown in Table 1. A nozzle 2 with an inner diameter of 0.3 mm is attached to the bottom of the furnace body 1, and is pressurized with 2 kg/d of argon gas from the top. The cooling tank 3 contains cooling water at a temperature of, for example, 4°C, and is stirred by the stirrer 4 so that the cooling water reaches 1
．． It rotates at a flow rate of about 3 m/s. However, nozzle 2
When the stopper was opened, the molten metal was injected into the cooling water at a jetting speed of about 820 m/win, and metal particles as shown in Table 1 were obtained.

As is clear from Table 1, in Examples 1 to 6, the alloy composition was within the appropriate range, and amorphous metal particles with high sphericity and small variation in particle size distribution were obtained.

On the other hand, Comparative Example 1 has a large amount of Pd, so although it is amorphous, the sphericity is low and the particle size distribution is highly uneven. In addition, in Comparative Example 2, the amount of P is outside the appropriate composition range, the material becomes crystalline, has low sphericity, and has large variations in particle size distribution.

〔Effect of the invention〕

As explained above, according to the present invention, Ni-based spherical amorphous metal particles can be easily produced in large quantities, and the spherical amorphous metal particles obtained thereby have good sphericity, large particle size, and variation. It has a small particle size distribution and is extremely useful industrially, such as bearings, ballpoint pen tips, fillers,
It can be widely used for blasting materials, molding materials, sintered materials, etc.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of a device used in an embodiment of the present invention. 1... Furnace body 2... Nozzle, 3... Cooling tank 4... Stirrer

Claims (1)

[Claims] P is 12 to 25 at%, platinum group elements Pd, Pt, Ir,
Rh, Ru, Os alone or two or more elements are 0.1
Production of Ni-based spherical amorphous metal particles characterized by continuously injecting molten metal consisting of an alloy of ~76 atomic % and the remainder being substantially Ni into cooling water rotating in a fixed direction by a stirrer. Method.