JPH0243348A - Amorphous magnetic alloy - Google Patents

Abstract

PURPOSE:To obtain the title amorphous magnetic alloy easy to produce and having excellent mechanical characteristics, low magnetostriction, and excellent magnetic characteristics by specifying the composition of the alloy consisting of Fe, Co, Ni, Nb, Cu, and B. CONSTITUTION:The amorphous magnetic alloy has the composition shown by the formula MaTbBc. In the formula, M is at least one kind among Fe, Co and Ni, T is a mixture consisting essentially of Nb and contg. <=10atomic% Cu, B is boron, (a), (b) and (c) are respectively atomic%, (a+b+c)=100, 60<=a<=95, 2<=b<=20, 0<c<=30, or preferably 0<c<=10. The amorphous magnetic alloy can be easily formed into a ribbon shape by the single roll method with good mass-productivity, and has a mechanical characteristic withstanding bend ing. In addition, the alloy has a low magnetostriction constant, and is appropri ately used for a magnetic head or a transformer.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic alloy for transformers that is easy to manufacture and has good mechanical properties.

BACKGROUND OF THE INVENTION In recent years, various amorphous magnetic alloys have become available using fishing boats using ultra-quenching technology. Historically, F
e-P-G, Go-P-B.

There have been reports that amorphous alloys such as Ni-B have been obtained, and it is still known that amorphous alloys can be obtained by combining P, G, B and transition metals. Among these, P has a high vapor pressure, which causes problems such as composition deviation and pollution problems.
On the other hand, C is not only difficult to form into a solid solution in the transition metal during melting.

There are many manufacturing problems such as separation and precipitation. For that reason.

Currently B is known to be the most effective element.

Currently, the two-roll method and the one-roll method have become mainstream as methods for producing amorphous magnetic alloys, replacing the methods described above. This is because previous methods can only yield unstable amorphous flakes, whereas these methods can easily yield ribbon-shaped amorphous magnetic alloys with a constant width and thickness. This is because the industrial advantages are large.

Furthermore, considering mass production, the single roll method is superior, and in practice it is desirable to obtain alloy thin strips (ribbons) by the single roll method.

However, an amorphous magnetic alloy having a composition consisting of a combination of a transition metal and boron, with a width of about 11, can be obtained relatively easily by the double roll method.

With the single roll method, at best, only a midrange sound of about 1 to 2M can be obtained. If you try to obtain a width wider than this, cooling will not be sufficient with the single roll method, so even when the solidified ribbon is separated from the roll and wound, the temperature of the ribbon will be 400~SOO''Cti. The ribbon oxidizes and discolors.However, the amorphous magnetic alloy obtained in this way does not originally have the mechanical properties that amorphous alloys have to withstand 180° bending, and is extremely brittle. This amorphous magnetic alloy not only had poor mechanical properties, but also had unfavorable magnetic properties.Therefore, (Fe-Go-Ni)-B based amorphous magnetic alloys with good properties It was extremely difficult to obtain a wide ribbon shape using the single roll method.

In addition, we improved the (Fe-Go-Ni)-B system (
(Fe-Go-Ni) -Zr system, (Fe-Go-Ni
) -Zr-B system, etc. have been announced, and these materials can be used to easily obtain a wide amorphous ribbon by a single roll method compared to the conventional (Fe-Go-Ni)-B system. However, since these Zr-containing alloy systems are extremely susceptible to oxidation, it is extremely difficult to melt the mother alloy in air and ultra-quench it using a single roll method to form an amorphous alloy.

Furthermore, although alloys containing Fe as the main component are preferable from a cost perspective, conventional Fe-B and Fe-8i-B have a large magnetostriction constant of approximately 30 x 10-6, and when stress is applied to the alloy, the characteristics deteriorate significantly. There is a problem of deterioration. Therefore, since there is no Fe-based amorphous alloy with a small magnetic layer, Go-based amorphous alloys with low magnetostriction have been used for magnetic heads and high-performance transformers, although they are expensive.

Problems to be Solved by the Invention The present invention aims to solve these problems, and provides an Fe-based amorphous magnetic alloy that is easy to manufacture and has good properties.

Means for Solving the Problems In the present invention, the above problems are solved by adding Nb and Cu to the (Fe-Go-Ni)-B system.

By adding Nb, a wide alloy ribbon can be obtained very easily even with the multi-piece roll method, and by adding Cu at the same time, a magnetic alloy with extremely low magnetostriction and excellent magnetic properties can be obtained even in the IBFe system. can get.

The present inventors have investigated the effects of various additives.

It has been discovered that the addition of Nb to this (Fe-Go-Ni)-B system is extremely effective, and that a wide amorphous magnetic alloy ribbon can be obtained extremely easily even with a single roll method.

The present invention is based on this.

First, to explain the addition of Nb, as a result of actual tests, it was found that the composition range in which amorphous formation is likely to occur is within the following range of alloys.

(Fe-Go-Ni) 1LNbbB0 However, a
, b, and c represent atomic crabs under the condition that a+b+C=1 oo.

6.7 6o≦a≦95 2≦b≦30 o(c≦30) Especially when trying to easily obtain an amorphous ribbon having a width of 41 or more and a thickness of 40 μm or more.

It is sufficient that 6≦b≦3°. Also, the conditions for an amorphous alloy to have magnetism, and the conditions for preventing oxidation when attempting to produce an amorphous alloy in air.

2≦b≦20 It is desirable that

FIG. 1 shows the experimental results regarding the coercive force HO and the embrittlement coefficient ef in the bending test when an alloy film of Fe'80-JCNbX B20 was produced by the single roll method.

6f is obtained from the following equation.

However, here, t is the thickness of the sample, r is the minimum radius of curvature at which bending failure occurs, p, and if complete bending of 180' is possible, θf=1.

From the results shown in the figure, it can be seen that the addition of Nb not only facilitates the production of alloy ribbons, but also has the effect of improving magnetic properties.

As is well known, conventional M (-Fe, co, Nl)
It is known that a 100-CBC alloy becomes amorphous unless C≧15 (atomic CX), and that saturation magnetization σ8 decreases as B increases. On the other hand (M-Nb) Boo
-cc alloys become amorphous even when pB is less than 15% by adding Nb, but by adding the non-magnetic element Nb, the saturation magnetization σ8 is Mlo
It is lower than the o-0B0 alloy.

Therefore, if a high value of σ8 is required.

c ku1゜ It is desirable to do so.

Now, the magnetostriction constant λ of the Fe-B system is about 3X10', but by adding Nb to it to form the Fe-Nb-B system, λ is reduced to about 1X10'. What is even more interesting is that when Cu is added together with Nb, Fe has extremely low magnetostriction.
It was found that a magnetic alloy of the system can be obtained. However, if a large amount of Cu is added, the alloy will become brittle and it will be difficult to make it amorphous, so it is desirable that the amount added be 10 or less.

Example Alloy ribbons were prepared by adding Nb and Nb and Cu to a Fe--B alloy, and their magnetostriction constants λ were measured.

The results are shown in the table below.

As can be seen from the results shown in the table, conventional Fe −B−
The Fe-Nb-C of the present invention can obtain an alloy with extremely low magnetostriction, which has been impossible to obtain with (Si)-based amorphous alloys.
It can be seen that this was made possible by the u-B system.

It has been found that even when a few atoms of CO or N1 are added to the Fe--Nb--Cu--B system, a product with low magnetostriction can still be obtained.

Effects of the Invention According to the present invention, it is possible to obtain an amorphous magnetic alloy that is easy to manufacture and has an extremely small magnetostriction constant and is suitable for magnetic heads and transformers.

[Brief explanation of the drawing]

Figure 1 is a characteristic diagram of coercive force Hc and embrittlement coefficient ef with respect to the addition amount X of Fe8o-xNbxB2o, and Figure 2 is a characteristic diagram of M
(=Fe, Cu, Ni)1oo-oBo system and (M”)
The relationship between the saturation magnetization σ8 and B content of a too-cBc alloy is shown. Name of agent: Patent attorney Shigetaka Awano and one other person Figure f Figure

Claims (2)

[Claims] (1) Formula: MaTbBc (where M is at least one member selected from the group consisting of Fe, Co, and Ni, T is Nb as a main component, and Cu is 10
A mixture containing atomic% or less, B is boron; a, b and c are atomic%, and under the condition that their sum is 100, 60≦a≦95, 2≦b≦20, 0<c, respectively. ≦30). (2) The amorphous magnetic alloy according to claim 1, wherein 0<c≦10.