JP2575041B2 - Molded body of amorphous alloy powder and molding method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a molded product of an amorphous alloy powder having an improved filling factor and a method for producing the same.

(Prior art) A method of forming a three-dimensional molded product from an amorphous alloy can be roughly classified into (i) a method using a bullet impact force and an explosive force of a gunpowder (for example, a summary of a lecture by the Japan Institute of Metals). , October 1984, p. 541), and (ii) those utilizing a softening phenomenon accompanying a glass transition of an amorphous alloy (for example, HHLieber-mann; Mat. Sci. And Eng. 46 (198)
0) p. 241), and (iii) a molded article obtained by using a binder (for example, JP-A-60-165303). That is, among these, (i) and (ii) require an extremely large molding pressure to give a permanent deformation to an amorphous alloy, which is generally said to be difficult to process, to obtain a molded body having a high filling factor. It is not suitable for industrial use because it requires, and the production efficiency is low and the cost is high. The reason is that most amorphous alloys do not clearly show the softening phenomenon accompanying the glass transition behavior from the amorphous solid state to the supercooled liquid state even when heated just below the crystallization temperature, so that the conventional crystalline This is because it is generally more difficult to process a granular material than an alloy. As described in (iii), in the method of obtaining a molded body using a binder, the main purpose of using the binder is to secure the mechanical strength of the amorphous alloy molded body or to improve the insulating property between the granular material layers. For that reason. Therefore, high molding pressure and heating are required to improve the filling rate even in an amorphous alloy molded body using a binder (for example, in the example of JP-A-60-165303, the molding pressure is 1.02 GPa. The heating temperature is in the range of 200 to 350 ° C.), and as described above, there has been a problem that the molding apparatus becomes large-sized, the cost increases, and the process becomes complicated. Therefore, it has been difficult to say that a method using a binder is also suitable for the purpose of producing a three-dimensional molded product of an amorphous alloy having a high filling factor on an industrial scale.

In fields other than amorphous alloys, for example, in the field of crystalline magnetic materials, studies for improving the filling rate of a compact have been reported. That is, they are based on (i) studies on the components of resins (eg, iron and steel, 71 (5) 1985, 489).
Page), (ii) Research on the use of resin in which inorganic compound fine powder is dispersed and mixed (for example, Proceedings of the 8th Symposium on Composite Materials, 1983, p. 63), (iii) Powder surface using organic coupling material, etc. (For example, iron and steel, 71 (3), 1985, S1573). However, when the above (i) to (iii) were applied to the amorphous alloy particles, no remarkable effect of improving the filling rate was observed.

(Problems to be Solved by the Invention) The present invention provides excellent physical and mechanical properties due to the characteristics of the microstructure.
An object of the present invention is to provide a three-dimensional molded body having an improved filling factor from an amorphous alloy powder having chemical properties while maintaining the amorphous state of the amorphous alloy, and a method of manufacturing the same on an industrial scale. And

(Means for Solving the Problems) The present invention relates to a molded article obtained by mixing a binder mainly composed of a resin with an amorphous alloy powder containing 0.01 to 3 atomic% of S and compressing and molding the same. Amorphous alloy powder or granule characterized by improving the filling rate of an amorphous alloy compact by mixing and compression-molding a binder mainly composed of a resin with amorphous alloy powder containing 0.01 to 3 atomic%. This is a molding method.

 Hereinafter, details of the present invention will be described.

The amorphous alloy referred to in the present invention is an alloy of a metal and a metalloid or a metal and a metal, which is mainly produced by a liquid quenching method and shows an amorphous state. The alloy component is an alloy of a metal and a metalloid, for example, one or more of metals such as Fe, Co, Ni, Cr, Mo, etc.
B, Si, C, P, and Ge. Examples of components in the case of a metal-metal alloy include Fe-Ti, Fe-Zr, and Cu-Ti. In the present invention, those containing 0.01 to 3 atomic% of S as an additive element to these component elements are used. The content of each element is selected on the condition that at least 90% of the element becomes amorphous at a cooling rate of 10 ⁴ ° C / sec or more.

The content of S added to the alloy component is 0.01 to 3 atomic%.
Range. If the content of S is less than 0.01 atomic%, the effect of improving the filling rate is not certain, and if the content of S exceeds 3 atomic%, the amounts of the basic components and the metalloid components are reduced and the original properties as an amorphous alloy are affected. This is because the

Examples of a method for producing an amorphous alloy foil, a fine wire, a powder, and the like (hereinafter referred to as a granular material) used as a raw material in the present invention include a single roll method, a twin roll method, and a centrifugal method capable of producing a foil. For example, there is a spinning in liquid spinning method. Amorphous alloy powder can be prepared directly by atomizing, cavitation, submerged jetting, plasma spraying, mechanical alloying (MA), mechanical grinding (MG), etc. There is an indirect method of pulverizing with a ball mill or the like, and any method may be used.

Also, powders obtained by different methods may be mixed and used.

Although there is no particular limitation on the method of compression molding of the granular material, for example, a single-acting or double-acting pressing device, a hydrostatic compression device (CIP), an extrusion device, or the like is used. As a raw material of the compact, a binder mainly composed of a resin is mixed in a range of 0.5 to 10% by weight with respect to the amorphous alloy particles in addition to the above-described amorphous alloy particles.

Examples of the binder that can be used include (i) a thermosetting resin such as a phenol-based or epoxy-based resin, (ii) a thermoplastic resin such as a nylon-based or vinyl chloride-based resin, and (iii) a polysulfide-based or nitrile rubber-based resin. Elastomeric resin, (i
v) One or a mixture of two or more such as anaerobic resins. The difference in the purpose of use of the binder depends on the performance and the pressing temperature required for the amorphous alloy compact. For example, a thermosetting resin is preferably used in the case of a molded article requiring shear strength and heat resistance or molding at a relatively low temperature near room temperature. Further, it is desirable to use a thermoplastic resin for a molded body requiring a peel strength or a molded body requiring a higher filling rate, and to mold at a high temperature just below the crystallization temperature. Further, when an impact force is applied to the molded body or when elastic performance is strongly required, it is preferable to use an elastomeric resin. The anaerobic resin can be easily cured by expelling air by pressurizing even at room temperature. Therefore, it is preferable to use the anaerobic resin in a field in which productivity is rationalized, labor saving and automation are strongly desired. These binders are mixed in the range of 0.5 to 10% by weight with respect to the amorphous alloy particles. 0.5
If the binder is used in an amount of less than 10% by weight, sufficient strength cannot be obtained in the molded article, and if the binder is used in an amount of more than 10% by weight, the amount of the binder used increases, which is not economically advantageous. This is because a sufficiently high filling rate can be imparted to the molded article by adding a small amount of S due to the properties of the present invention, so that the excess binder may lower the filling rate at the time of molding.

The compression molding temperature is limited to a temperature range in which the amorphous alloy particles do not crystallize due to the properties of the present invention, but is preferably equal to or lower than the heat-resistant limit temperature of the binder containing resin as a main component. The molding pressure is preferably in the range of 100 MPa to a maximum of 1.5 GPa because the pressurizing tool must be used continuously. The present invention also has a feature that the pulverizing step can be simplified by adding S.

As described above, it can be said that the present invention is a very excellent invention in that the addition of a small amount of S greatly improves the packing ratio of the amorphous alloy particles without greatly changing the composition of the amorphous alloy. This fact is because the method of the present invention can reduce the pressing force compared to the forming method of the amorphous alloy formed body using a hot press or the like, so that the load on the mold die is light, and no special heating device is required. It is characterized in that it can be easily molded in the atmosphere. In addition, compared to the compression molding method using a conventional resin as a binder, the filling rate of the amorphous alloy particles is higher, the mixing amount of the binder is small, and the pulverization is easy. It can be said that this is a very useful forming method in an industrial process that consumes a large amount of amorphous alloy particles.

(Example) Example 1 Alloy composition is Fe _72-x Co ₁₀ Mo ₂ C ₄ B ₁₂ S _x atomic% (x = 0, 0.2
Batch-type roulette mill (Yoshida Seisakusho 1036-A type 0) with 25mm wide and 50μm thick amorphous alloy foil made with a single roll of Cu alloy (peripheral speed 1.4m / s) at 5,0.5,1.0) .
Crushed using 75kw), -100 + 200 mesh (74-14 mesh)
Classified in 9). When x = 0 was converted to 1, for example, the time required for pulverization was about 1/25 of that at x = 1.0.

3% by weight and 3.0g of this amorphous alloy powder
10% by weight of anaerobic resin (LO manufactured by Nippon Loctite Co., Ltd.)
Using CTITE 290) as a binder, pressurizing force 620MPa, pressing time 10
A compression molded body (cylindrical shape of φ12 mm) was produced under the same conditions of sec. FIG. 1 shows the effect of the addition of S on the density (and the filling factor) of the compact.

10% by weight of a binder was mixed as the binder (Fig. 1
Marks) The compact densities of alloys with x = 0, 0.25, 0.50, 1.0 are 4.80 g / cm ³ , 5.04 g / cm ³ , 5.02 g / cm ³ , 5.34 g / cm ³ , respectively, and Fe ₇₂ Co ₁₀ The filling rate of the compact, calculated assuming that the density of the Mo ₂ C ₄ B ₁₂ atom% amorphous alloy foil is 7.77 g / cm ³ as 100%, is x
From 61.7% of x = 0 to 64.9% of x = 0.25, 66.9 of x = 0.50
%, X = 1.00 to 68.7%, and the addition of 1 atomic% of S increased the filling rate by 7.0%.

3% by weight of a binder was mixed (marked with a circle in FIG. 1).
The compact density (filling rate) of the alloy particles (74 to 149 μm) of 25, 0.50, 1.0 was 5.19 g / cm ³ at x = 0.25, 0.50, 1.0.
(66.8%), 5.54 g / cm ³ (71.3%), 5.58 g / cm ³ (71.8
%), Which indicates that the addition of S improves the filling rate as described above. In this case, the density of the molded body was improved by about 3% as compared with the case where 10% of the binder was used, and the filling of the molded body was improved by reducing the amount of the binder mixed to some extent. However, the decrease in the binder affects the compression moldability. When the alloy composition is x = 0 and the amount of the binder mixed is 3% by weight, a sound compact cannot be obtained, and density measurement is impossible.

Example 2 The alloy composition was Fe _4-x Co ₆₉ Mo ₂ Si ₁₆ B ₉ S _{x at} % (x = 0,1.
0) and Fe _75-x Ni ₅ Mo ₄ C ₄ B ₁₂ S _x atomic% (x = 0,1.0)
After pulverizing and classifying the amorphous alloy foil made of under the same conditions as in Example 1, compression molding was performed using a powder having a particle size of 74 to 149 μm. Table 1 shows the results. Fe ₄ Co ₆₉ Mo ₂ Si ₁₆
The density (filling rate) of the compact obtained by converting the density of 7.87 g / cm ³ and 7.83 g / cm ³ of the ₉ atomic percent B alloy and the Fe ₇₅ Ni ₅ Mo ₄ C ₄ B ₁₂ atomic percent alloy to 100%, respectively, is , Binder 3%, 5.61 g / cm ³ (71.3%) at x = 1, 5.59 g / cm ³ (71.4%), binder 10%, 5.49 g / cm ³ (69.8%) at x = 1, 5.50 g
/ cm ³ (70.2%). However, in the case of the amorphous alloy powder having the above composition of x = 0, in which the binder was mixed at 3% by weight and 10% by weight, a compact whose density could be measured was not obtained despite the same compression molding conditions.

3% by weight of thermoset _{Fe 71 Co 10 Mo 2 C 4} B 12 S 1 atom% amorphous alloy powder grains of pulverization and classification were -100 + 200 mesh (74~149μm) in the same manner as in Example 3 Example 1 2 (a) and 2 (b), a molded article having the shape shown in FIG. 2 (c) was used as a binder. Produced. The molding conditions were a pressing force of 550 MPa, a pressurizing time of 10 sec, a curing temperature of 160 ° C. × 90 min, and a floating mold was used as a mold.

The density of the obtained green body was 5.60 to 5.63 g / cm ³ , and the filling rate of the green body obtained by converting the density of the amorphous alloy foil from 7.77 g / cm ³ to 100% was in the range of 71.9 to 72.5%.

(Effects of the Invention) According to the present invention, a powder compact of an amorphous alloy can be formed into a compression-molded body having an improved filling factor by a simple method. In addition, the addition of S can simplify the process of pulverizing fine wires of the amorphous alloy foil, so that the production cost of the granular material can be reduced. This makes it possible to use amorphous alloys whose use fields are limited because their shapes are limited to powders, foils and thin wires, in a wider field. Further, since there is no need for complicated steps in the manufacturing process and no particular need for rework after molding, it has the feature that it can be mass-produced at low cost on an industrial scale.

The molded product obtained by the present invention is an effective material in the field of magnetic materials and the like.

For example, using an amorphous alloy having magnetic properties as a raw material, a core material and a variety of magnetic sensor materials whose filling factor is improved by the method of the present invention can be produced. By processing it into a sheet, its application to magnetic shield materials can be expected.

[Brief description of the drawings]

FIG. 1 shows the effect of S addition on the density of the resin molded product of the amorphous alloy powder. ○ indicates the case where the mixing amount of the binder was 3% by weight, and ● indicates the case where the mixing amount of the binder was 10% by weight. 2 (a), 2 (b) and 2 (c) show the shape of the molded article produced in Example 3. FIG.

Claims (2)

(57) [Claims] An amorphous alloy powder containing 0.01 to 3 atomic% of S is mixed with a binder mainly composed of a resin.
A compact of amorphous alloy powder obtained by compression molding. 2. A method for improving the filling rate of an amorphous alloy molded body by mixing a binder mainly composed of a resin with an amorphous alloy powder containing 0.01 to 3 atomic% of S and compressing and molding the mixture. Characteristic method of forming amorphous alloy powder.