JPS60131953A - Amorphous alloy - Google Patents

Abstract

PURPOSE:To obtain an amorphous alloy having superior resistance to corrosion and stress corrosion cracking and suitable for use as the material of a magnetic separating element by specifying a composition consisting of Fe, Ni, a metallic element such as Mo, a Pt group element and metalloids. CONSTITUTION:This amorphous alloy has a composition represented by a formula (Fe1-aNia)100-x-y-zLxMyNz (where L is at least one among Mo, W, Cr, Nb, Ti, Zr and Al, M is two or more among Si, B, P and C, N is at least one among Ru, Rh, Pd, Os, Ir and Pt, a is 0.2-0.6atom%, x is 0.5-10%, y is 15- 30% and z is 0.1-10%). The amorphous alloy has high strength, high corrosion resistance and especially superior resistance to stress corrosion cracking, and it is suitable for use as the material of a magnetic separating element having a high gradient. The amorphous alloy is obtd. by solidifying a molten alloy having said prescribed composition by very rapid cooling before crystallization takes place so as to form a glassy solid.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic separation element for efficiently adsorbing and separating magnetic particles mixed in a liquid using a small magnetic field as one use for amorphous alloys.

Conventionally, ferromagnetic alloys such as magnetic stainless steel have been used as high gradient magnetic separation elements. However, because these have a high residual magnetic flux density, these multi-component filters
Requires a large amount of cleaning fluid during regeneration. In addition, due to poor corrosion resistance, rust forms on the metal surface, and during operation of the high gradient magnetic separation apparatus, the rust separates and mixes into the processing liquid. As a result, ferromagnetic alloys such as magnetic stainless steel have the disadvantage of reducing magnetic separation efficiency.

In order to solve these problems, amorphous soft magnetic alloys, which have excellent properties such as low residual magnetic flux density and high corrosion resistance, have attracted attention in recent years. Due to manufacturing characteristics, amorphous alloys are mainly obtained as continuous ribbons, and when used as magnetic separation elements, it is necessary to form narrow ribbons due to the magnetic separation mechanism.

The present invention was obtained as a result of intensive research to solve the drawbacks of conventionally used crystalline ferromagnetic alloys and amorphous ferromagnetic alloys, as described above. )100-X-y-2LXMyNz
However, L is at least one kind selected from Mo, W+Cr, Nb+Ti +Zr and At, M is Si, at least two kinds are selected from rB+P and C, N is at least one kind selected from Ru+Rh+Pd+Os+Ir and pt, and a is 0.2 to 0. .6 (at%) X is 0.1 to 10 (at%) y is 15 to 30 (at%) 2 is 0.5 to 10 (at%) It is an amorphous alloy with excellent properties.

Next, one aspect of the present invention will be explained in detail.

Amorphous alloys are obtained by ultra-rapidly cooling a molten metal with a composition near the eutectic point, solidifying it before crystallization occurs and forming a glass-like solid, and it lacks a regular atomic arrangement over a long period of time. It is an alloy. The present inventor has found that: (1) the amorphous alloy having the specific component composition of the present invention has high strength;
It has been discovered that this amorphous alloy has excellent corrosion resistance, particularly stress corrosion cracking resistance, and has properties as a magnetic separation element.

Table 1 shows the composition, magnetic properties, corrosion loss, and stress corrosion cracking of the amorphous alloy of the present invention, the amorphous alloy outside the composition range of the present invention, and the conventionally used stainless steel magnetic wire (STJS 410). This is a table showing the time and intensity required for this. However, Bloo has an applied magnetic field of 100 (O
This is the magnetic flux density at the time of e). The amount of corrosion is determined by immersion in 1 N hydrochloric acid (hereinafter referred to as 1 N-HCt) at 32°C for 100 hours.
I calculated the weight change.

The time required for margin stress corrosion cracking is shown below using a glass rod (1.8 mmφ) for thin strips and thin wires. The tips of each roll were glued together in a spiral shape, and the time was set at 32°C and 1 NLHcz until the ribbon and wire broke. (The sample dimensions of the amorphous alloy are approximately 1 mm in width and approximately 25 μm in thickness.

Stainless steel magnetic wire (SUS 410) is 0.1 myn
A commercially available fine wire of φ was used. ) Samples A1 to A6 shown in Table 1 are representative examples of amorphous alloys according to the present invention, and have good corrosion resistance, and are particularly significantly improved compared to amorphous alloys outside the composition range of the present invention that suffer from stress corrosion cracking. ing. Furthermore, compared to stainless steel magnetic wire, the amorphous alloy of the present invention is significantly superior in terms of the amount of corrosion.

Figure 1 shows (Fe 1 aNI a) 7BS 110B
9R1I 2T l Magnetic flux density (B100) when the a value (Fe,!:Ni composition ratio) is changed in an amorphous alloy having the composition (atomic %) of 1 'Time to reach stress corrosion cracking and corrosion weight loss Show rate. (The measurement method is the same as described above.) As is clear from Figure 1, the stress corrosion cracking shows the lowest value in the amorphous alloy with the component composition of B=Q, Q5~o, and 15, and about 30% It breaks at a certain degree. Also, a=0.2
~0.8, stress corrosion cracking is less likely to occur. On the other hand, corrosion weight loss is not affected by the a value and is strongly affected (a≧0.1 is desirable.Amorphous alloys change to crystalline alloys at a certain temperature depending on the component composition, and as amorphous alloys Characteristics are lost.

(This temperature is in the range of about 400-500°C.) When the amorphous alloy is used as a magnetic separation element.

The welding method is difficult (for the reasons mentioned above). Therefore, when producing a magnetic separation filter, it is possible to fill a filter tank with a thin strip of amorphous alloy or wrap it around a support.
It is difficult to avoid stress applied to the amorphous alloy ribbon. Therefore, improvement of stress corrosion cracking is extremely important.

As mentioned above, the amorphous alloy of the present invention has good corrosion resistance, and is particularly excellent in stress corrosion cracking.

Next, the principle of the high gradient magnetic separation method will be explained.

Magnetic field strength H1 magnetic field gradient d)]; /dx 1 volume V in O.

The force F that acts on magnetic particles with magnetization M is expressed as H F (X-M・■・□ Separation is possible.

In FIG. 2, two amorphous alloy ribbons according to the present invention were used. 1 is a diagram showing an example of a magnetic separation device.

Moreover, FIG. 3 is a diagram showing the magnetic particle adsorption rate when the applied magnetic field is changed in FIG. 2.

(Fe0.6N10.4)785i10B which is the present invention
9Ru2Ti0.5 atomic ratio width 0.1 mm +
From the relationship between the applied magnetic field and the magnetic particle adsorption rate using an amorphous alloy ribbon with a thickness of about 25 μm, it can be seen that the amorphous alloy according to the present invention has an excellent magnetic particle adsorption rate when compared with stainless steel magnetic wire. . (The magnetic particles are iron oxide Fe3O4 powder.

The magnetic particle adsorption rate is calculated based on the concentration of iron oxide contained in the aqueous solution before flowing, and the concentration of iron oxide remaining in the aqueous solution after being adsorbed and separated by flowing under each applied magnetic field. did. ) From the above, the amorphous alloy of the present invention is superior to fine wires of crystalline alloys in terms of corrosion resistance, particularly resistance to stress corrosion cracking.
It is most suitable as a high gradient magnetic separation element.

Next, the reason for limiting the component composition in the amorphous alloy of the present invention will be explained.

Composition formula (Fe1-aNia)100, -y-2LXM
In yN2, iron to nickel ratio a is 0.2 < a
The reason for limiting the value to <0.6 is that a(0,2) tends to cause stress corrosion cracking and cannot be used as a magnetic separation element.
0) decreases, and sufficient characteristics as a magnetic separation element cannot be obtained. Therefore, the iron/nickel ratio a was limited to the above range.

L is Mo +W, Cr +Nb, Ti, Zr +A
A is an element that improves the corrosion resistance and stress corrosion cracking resistance of the amorphous alloy of the present invention through a synergistic effect with platinum group elements. At the composition ratio X of L, x(0,1
With x) of 10, the magnetic flux density (B100) decreases and sufficient characteristics as a magnetic separation element cannot be obtained. Therefore, it was limited to 0.1 < x < 10 atoms. Here, it is more preferable that l < x < 7 atoms.

The reason why the metalloid element M is at least two selected from Si+B+P and C, and is limited to 15<y≦30 atoms, is that when y<15 atoms, it becomes amorphous and the amorphous alloy is difficult to obtain. Also, in the case of y>30 atoms, as in the case of X<15 atoms, it becomes amorphous and the magnetic flux density decreases significantly, making it impossible to obtain sufficient characteristics as a magnetic separator. Therefore, it was limited to 15<y<30 atoms.

The platinum group element N is at least one selected from Ru+Rh, Pd+0s+Ir+Pt, and O65<z<10
The reason for limiting it to atomic hydrogen is that z (0,5 atomic hydrogen does not improve corrosion resistance and stress corrosion cracking resistance, and Z〉1
With zero atoms, the magnetic velocity density (B100) decreases and sufficient characteristics as a magnetic separation element cannot be obtained. Therefore.

Q, 5<z<IQ atoms are limited. Here 1≦z<
More preferred is 6 atoms.

[Brief explanation of the drawing]

Figure 1 is + (Fe1-a”a)78 5i1oB, R
FIG. 2 is a diagram showing the time to stress corrosion cracking, corrosion weight loss rate, and magnetic flux density (B100) when iron and Nysogal ratio a are changed in an amorphous alloy having a composition of u2Ti1. FIG. 2 is a diagram showing an embodiment of a magnetic separation device using the amorphous alloy ribbon of the present invention as a magnetic separation element, in which 1 is a frame, 2 is a supply pipe, 3 is a drainage pipe, and 4 1 is a magnetic separation element (an amorphous alloy ribbon according to the present invention), 5 is a wire mesh, 6 is a magnetizing coil, 7 is a pre-treatment fluid containing fine particles, etc., and 8 is an overtreated fluid. FIG. 3 is a diagram showing the magnetic particle adsorption rate when changing the applied magnetic field. Figure 1 Q (at7.) Figure 2 Figure 2 The present invention's magnetic field (Oe)

Claims (1)

[Claims] 1. In atomic concentration (Fe 1-8Nia) 100-x
-y-z LxMyN2 (L is Mo +W+Cr
+Nb +Ti +At least one selected from Zr and At. M is at least two or more selected from Si, B, P, and C. N is at least one selected from Ru+Rh+Pd+Os+Ir and pt. a id 0.2~0.6 (at%)X is 0.5~1
0 (at%) y is 15 to 30 (at%) 2 is 0.1 to 10 (at%)) An amorphous alloy having excellent corrosion resistance and stress corrosion cracking resistance. Remaining days below