JPH0440403B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing Ni-based spherical amorphous metal particles. [Prior art and its problems] Ni has traditionally been excellent in 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.
In addition, it is widely used as various magnetic materials due to its properties, and is also widely used as a catalyst material, making it an extremely important metal element industrially. Furthermore, by using an alloy with a composition containing Ni, the alloy having an amorphous state can be produced using a liquid quenching method.
P, Ni-B, Ni-P-B, Ni-Si-B, Ni-Pd
-P, Ni-Pd-Si, Ni-Pt-P, Ni-Pt-Si,
Ni-Cr-P, Ni-Mo-C, Ni-Al-B, Ni-
It is obtained from alloy systems such as Zr, Ni-Hf, and Ni-Nb, and most of the samples in these cases are thin strips with a thickness of about 10 to 30 μm, which is the most difficult sample among liquid quenching methods. One-roll method that makes it easy to make
The method used was the piston anvil method. 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 even more so, the rotating liquid spinning method, which is a liquid quenching method that saves energy, has been developed. 56-165016), and Ni
-High-quality thin metal wire with a cross-sectional circularity of 90% or more and a very uniform shape with wire diameter unevenness of 4% or less due to the alloy system of Pd-Si and Ni-Pd-P. is produced continuously. (Refer to Japanese Patent Application Laid-Open No. 60-59032). However, the ribbon-shaped materials and fine wire-shaped materials obtained in this way have restrictions on their uses due to their shape, and are difficult to process into bulk materials.
Furthermore, it is difficult to process it into industrially useful spherical metal particles. In addition, as a method for obtaining amorphous spherical metal particles,
Dropping molten metal into cooling water, dividing molten metal with a filter, screen, rotating plate, jet flow, etc. and cooling it in the liquid, or placing molten metal in cooling water with a screen or rotating plate, etc. This method involves dividing the material into spheres by dividing the material into spheres. Furthermore, it has been obtained by the atomization method, the disk quenching method, the jetting method in a rotating liquid, 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 are small in particle size and almost powder-like, and large particles have not been obtained. [Object of the Invention] In view of these circumstances, the purpose of the present invention is to provide a method for easily producing Ni-based spherical amorphous metal particles with large particle diameters that are extremely useful industrially and with good mass productivity. It is something to do. [Structure of the Invention] The present inventors discovered that when a Ni-based alloy having 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. They have discovered that Ni-based spherical amorphous metal particles with small variations in particle size distribution can be obtained with good mass production, and have completed the present invention. In other words, the composition range is 8 to 25 atomic% P, and B
0.1-12 atomic%, platinum group elements Pd, Pt, Ir, Ru,
The alloy contains 0.1 to 72 atomic percent of one or more of Rh and Os, and the remainder is essentially Ni. In addition, in these compositions, the nozzle diameter is 0.06~
2.0 mm, the particle size is approximately 0.06 to 2.0 mm by continuously injecting the molten metal into the cooling water under conditions where the flow rate of the molten metal is 3 to 22 m/s, and the flow rate of the cooling water is 0.01 to 22 m/s. Spherical amorphous metal particles with high sphericity of mm 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 ratio is within about 2:1, and when it exceeds about 3:1, 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 needs to be at least 0.5 cm long.
If the length of the molten metal flow is less than 0.5 cm, 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 must be 15 degrees or more. 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 8 to 25 at %, and more preferably 12 to 20 at %. When the amount of P is outside the range of 8 to 25 at %, the ability to form an amorphous state is significantly reduced. Similarly, if the amount of B is outside the range of 0.1 to 12 at %, the ability to form an amorphous state will be significantly reduced. Furthermore, the content of platinum group elements such as Pd and Pt is required to be 0.1 to 76 at %, more preferably 12 to 70 at %. This amount
Although it is in an amorphous state when it exceeds 70 atom%,
It becomes difficult to become spherical, and the sphericity and hardness decrease. On the other hand, if the content is less than 0.1 atomic %, the ability to form an amorphous state is significantly reduced. The remainder is essentially made of Ni,
It may contain impurities to the extent present in ordinary industrial materials, and furthermore, in order to improve mechanical properties, W, Co, Cr, Fe, Mn, Nb, Ta,
There is no hindrance to adding V, Mo, Ti, etc., or dispersing WC, TiC, etc. The spherical particles obtained by the present invention have very good sphericity, and have a sphericity of at least 95% or more. These spherical grains can be subjected to continuous cold working, and in order to further improve dimensional accuracy and mechanical properties, processing such as wrapping can be performed, and if necessary, heat treatment such as annealing can be applied. can also be done. [Example] Next, the present invention will be explained in more detail with reference to Examples. The furnace body 1 is filled with molten alloys having various compositions shown in Table 1. The bottom of the furnace body 1 has an inner diameter of 0.1
mm nozzle 2 is installed, and 4 mm from the top.
Pressurize with argon gas of Kg/ ^cm2 . The cooling tank 3 contains cooling water at, for example, 4° C., and is stirred by the stirrer 4 to rotate at a flow rate of about 1.3 m/s. When the stopper of nozzle 2 was opened, the molten metal was injected into the cooling water at a spouting speed of about 520 m/min, and metal particles were obtained as shown in Table 1.

〔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 and large particle size. It has a particle size distribution with small variations and is extremely useful industrially, such as bearings, ballpoint pen tips, fillers, blasting materials, etc.
It can be widely used in molding materials, sintering materials, etc.

[Brief explanation of the drawing]

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
……mixer.

Claims (1)

[Claims] 1 P is 8 to 25 atomic%, B is 0.1 to 12 atomic%, platinum group elements Pd, Pt, Ir, Ru, Rh, Os, one or more elements are 0.1 to 72 atomic%, the balance is substantially A nozzle diameter of 0.06
~2.0 mm, the flow rate of the molten metal is 3 to 22 m/s, and the length of the molten metal flow is 0.5 cm or more. A method for producing Ni-based spherical amorphous metal particles, characterized by continuous injection so that the angle between the metal flow and the cooling water surface is 15 degrees or more.