JPH0765147B2 - Amorphous magnetic alloy - Google Patents

Description

TECHNICAL FIELD The present invention relates to an amorphous magnetic alloy which is easy to manufacture and has good mechanical properties. Further, the present invention has a small magnetostriction,
The present invention relates to a magnetic alloy having excellent magnetic properties for a magnetic head or a transformer.

2. Description of the Related Art In recent years, various amorphous magnetic alloys have come to be obtained due to the progress of ultraquenching technology. Historically, Fe by the gun method or piston anvil method and splat quenching method, etc.
It has been reported that amorphous alloys such as -P-C, Co-P-B, and Ni-B have been obtained, and that amorphous alloys can be obtained by combining P, C, B and transition metals. Are known. this house,
P has a high vapor pressure and causes problems such as compositional deviation and pollution problems. On the other hand, C is not only difficult to form a solid solution in the transition metal during melting, but also a manufacturing problem such as separation and precipitation. There are many points. Therefore, it is currently known that B is the most effective element.

As a method for producing an amorphous magnetic alloy, at present, a double roll method or a single roll method has become mainstream in place of the above-mentioned method. This is because while the previous method can only obtain unstable amorphous flakes, it is possible to easily obtain a ribbon-shaped amorphous magnetic alloy with a constant width and a constant thickness by using these methods. This is because it has great industrial advantages.

Further, considering the mass productivity, the one-roll method is superior, and it is desirable in practice to obtain an alloy ribbon (ribbon) by the one-roll method.

However, an amorphous magnetic alloy having a composition consisting of a combination of transition metal and boron is relatively easy to be 1 cm by both roll methods.
Although widths of about 1 to 2 mm are obtained at most by the single roll method. If you try to obtain a wider width than this, the single roll method will not provide sufficient cooling, so even when the solidified ribbon is separated from the roll and taken up, the ribbon temperature is as high as 400 to 800 ° C. The ribbon oxidizes and discolors. Further, the amorphous magnetic alloy obtained in this manner was extremely brittle because it did not have the mechanical properties of the amorphous alloy that can withstand 180 ° bending. This amorphous magnetic alloy was not only inferior in mechanical properties but also in magnetic properties. Therefore, it has been extremely difficult to obtain an amorphous magnetic alloy of the (Fe-Co-Ni) -B type having good characteristics by the single roll method in the form of a wide ribbon.

In addition, (Fe-Co-Ni) -B system is improved (Fe-Co-Ni)
-Zr system, (Fe-Co-Ni) -Zr-B system, etc. have been announced, and these materials are more easily processed by the single roll method than the conventional (Fe-Co-Ni) -B system. A crystalline ribbon can be obtained. However, since these Zr-containing alloy systems are extremely susceptible to oxidation, it is extremely difficult to melt the mother alloy in air and rapidly quench it by the single roll method to form an amorphous alloy.

Further, in terms of cost, an alloy containing Fe as a main component is preferable, but conventional Fe-B and Fe-Si-B have a magnetostriction constant of about 30 × 10.
^It is as large as ^-6, and there is a problem that the characteristics are significantly deteriorated when stress is applied to the alloy. Therefore, since there is no Fe-based amorphous alloy with small magnetostriction, the cost is high, but Co with small magnetostriction is used.
Amorphous alloys were used for magnetic heads and high-performance transformers.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention solves such a problem, and provides an Fe-based amorphous magnetic alloy which is easy to manufacture and has good characteristics.

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

A wide alloy ribbon (ribbon) can be obtained very easily by the single roll method by adding Nb, and a magnetic alloy with extremely small magnetostriction and excellent magnetic properties can be obtained by adding Cu at the same time. .

As a result of examining the effects of various additives, the present inventors have found that the addition of Nb is extremely effective for this (Fe-Co-Ni) -B system, and the single-roll method makes it very easy to obtain a wide amorphous magnetic field. It was discovered that an alloy ribbon could be obtained. The present invention is based on this.

First, the addition of Nb will be described. As a result of experiments, it was found that the composition range in which amorphization is likely to occur is an alloy given in the following region.

(Fe-Co-Ni) _a Nb _b B _c where a, b, and c represent atomic%, and under the condition of a + b + c = 100, 60 ≦ a ≦ 95 2 ≦ b ≦ 30 0 <c ≦ 30 In particular, In order to easily obtain an amorphous ribbon having a width of 4 cm or more and a thickness of 40 μm or more, 6 ≦ b ≦ 30 should be satisfied. Further, it is desirable that 2 ≦ b ≦ 20 so that the amorphous alloy does not oxidize when it is produced under the condition that the amorphous alloy has magnetism and in the air.

Fig. 1 shows the coercive force Hc and the embrittlement coefficient e _{f in the} bending test when an alloy film Fe _80-x Nb _x B ₂₀ was prepared by the one-roll method.
The experimental results for are shown.

e _f is obtained from the following equation.

Here, t is the thickness of the sample, r is the minimum radius of curvature at which bending failure occurs, and e _f = 1 when 180 ° perfect bending is possible.

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

Known as the conventional M (= Fe, Co, Ni ) c ≧ 15 ( atomic%) not equal hardly amorphous at _100-c B _c alloy, also the saturation magnetization sigma _s decreases with increasing B Things are known. On the other hand (M-Nb) Although the _100-c B _c based alloy amorphized B even more than 15% by the addition of Nb, the saturation magnetization sigma _s by addition of a non-magnetic element Nb is first in the same B content As shown in Fig. 2, it is lower than the conventional M _100-c B _c alloy. Therefore, when a high value of σ _s is required, it is desirable that c ≦ 10.

The Fe—B system has a magnetostriction constant λ of about 3 × 10 ⁻⁵ , but by adding Nb to this to form the Fe—Nb—B system, λ is about 1 ×.
It drops to 10 ^-5 . More interestingly, it was found that when Cu was added together with Nb, a Fe-based magnetic alloy with extremely small magnetostriction was obtained. However, if Cu is added in a large amount, the alloy becomes brittle, and it becomes difficult to make it amorphous. Therefore, it is desirable that the addition amount be 10% or less.

Example An alloy ribbon was prepared by adding Nb and Nb and Cu to an Fe-B based alloy, and the magnetostriction constant λ was measured. The results are shown in the table below.

As can be seen from the results shown in the table, conventional Fe-B- (S
It can be seen that the Fe-Nb-Cu-B system of the present invention makes it possible to obtain an alloy having an extremely small magnetostriction, which was impossible to obtain with the i) system amorphous alloy.

It has been found that even if a few atomic% of Co or Ni is added to the Fe-Nb-Cu-B system, a material having a small magnetostriction can 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 is suitable for a magnetic head or transformer having an extremely small magnetostriction constant.

[Brief description of drawings]

Fig. 1 is a characteristic diagram of coercive force Hc and embrittlement coefficient e _f with respect to the additive amount x of Fe _80-x Nb _x B ₂₀ , and Fig. 2 is M (= Fe, Co, Ni) _100-c B _c
The relationship between the B content and the saturation magnetization σ _{s of the} (M-Nb) _100-c B _c system alloys is shown.

Claims (2)

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