JPS6261660B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a method for manufacturing a high magnetic permeability amorphous alloy, and particularly to a manufacturing method for improving effective magnetic permeability. [Technical background of the invention and its problems] Conventionally, high magnetic permeability metal materials used in magnetic heads, magnetic shields, transformers, and other magnetic devices include Fe--Si alloys and Fe--Ni alloys with crystal structures.
There are alloys, Fe--Al alloys, Fe--Si--Al alloys, etc., and each is used according to its characteristics, but each of these alloys still has problems with its characteristics and manufacturing. Fe-Si alloys are used as cores for transformers, motors, etc., but their magnetic permeability is low, around 500 at most. Among Fe--Ni alloys, permalloy containing 78 atomic percent Ni in particular has high magnetic permeability but insufficient hardness for practical use, so wear resistance is a problem when used as a magnetic head. Furthermore, when used as a magnetic head, it is molded with synthetic resin, but this has the disadvantage that the magnetic permeability is significantly reduced. Among Fe-Al and Fe-Al-Si alloys, those with high magnetic permeability are brittle, making plastic working very difficult, and their uses are extremely limited. Recently, excellent magnetic and mechanical properties have been discovered in amorphous alloys that do not have a crystalline structure. Amorphous alloys, unlike ordinary crystalline alloys, are alloys without periodicity of crystals, and can be obtained by various manufacturing methods. Up to now, amorphous alloys have been obtained by vapor deposition, electrodeposition, electroless plating, sputtering, liquid quenching, and the like. In particular, amorphous alloys obtained by the liquid quenching method are bulk-like, whereas those obtained by other methods are thin films, and have superior mechanical strength, hardness, and flexibility, making them suitable for magnetic heads. It is highly recommended as an amorphous alloy for cores and magnetic shields. However, the magnetic permeability of an amorphous alloy in a rapidly cooled state is generally low, and heat treatment is required to obtain high magnetic permeability. For example, as shown in JP-A-51-73923, Fe-based,
It is known that the maximum magnetic permeability of DC magnetization characteristics can be improved by annealing Co-based amorphous alloys in a magnetic field below the crystallization temperature. No consideration was given to improving effective magnetic permeability, which is an AC magnetization characteristic required for sensors and the like. [Object of the Invention] In view of the above points, an object of the present invention is to provide an optimal manufacturing method for improving the effective magnetic permeability of a Co-based amorphous alloy. [Summary of the Invention] The present invention relates to a high magnetic permeability amorphous alloy mainly composed of Co, particularly (Co _1-a Fe _a ) _1-x X _x , where X is B or a mixed system of B + Si (Si is 25 atomic% or less) a is
0.04 to 0.11, x is 0.20 to 0.28, and part of Co is M(Nb, V, Ta, Ti,
10 with at least one of Zr, Cr, Mo, W)
Using a material in which less than 1 atomic % of Co is substituted, or a part of Co in this composition is replaced with 10 atomic % or less of Ni and 10 atomic % or less of M, in a DC magnetic field at 120 ° C. This is a method for improving the effective magnetic permeability of a Co-based amorphous alloy, which obtains a high effective magnetic permeability by furnace cooling from a temperature within the range of 270°C to room temperature. The reason for specifying the temperature range for starting furnace cooling in a DC magnetic field in the present invention is as follows. Lower limit of temperature to start furnace cooling in DC magnetic field is 120℃
This is because if this temperature is less than 120℃,
The effect of improving the effective magnetic permeability of amorphous alloys cannot be obtained in the process of furnace cooling treatment in a magnetic field, and when the temperature exceeds 270℃, although the maximum magnetic permeability improves after furnace cooling treatment in a magnetic field, the effective magnetic permeability decreases. It is. The reason for limiting the content of each component in the high magnetic permeability amorphous alloy is as follows. The reason why a is limited to 0.04 to 0.11 in claim 2 is that the effective magnetic permeability decreases outside this range, and x is
The reason why the Si content is limited to 0.20 to 0.28 and 25 atomic % or less is that outside this range, not only is it difficult to produce an amorphous alloy, but also a large effective magnetic permeability cannot be obtained. In claim 3, the M or total M and Ni content is limited to 10 atomic % or less because if it exceeds 10 atomic %, it becomes extremely brittle and difficult to use in practice, and furthermore, the effective magnetic permeability decreases rapidly. Because it does. [Effects of the Invention] That is, according to the present invention, it is possible to improve the maximum magnetic permeability, which is a direct current magnetization characteristic, and to improve the effective magnetic permeability (approximately equivalent to the effective magnetic permeability), which is an alternating current magnetization characteristic. For example, when an amorphous alloy is used in the magnetic head according to the present invention, it is suitable because it has both the maximum magnetic permeability required for recording and the effective magnetic permeability required for reproduction. In addition, by improving the effective magnetic permeability, various types of alternating current (for example, commercial 50 to 60 Hz)
An amorphous alloy suitable for use as a microcurrent sensor such as a leakage current sensor can be obtained. [Examples of the Invention] The present invention will be described in detail below using Examples. (Example 1) The molten alloy was rapidly cooled by the rolling quenching method, that is, by jetting the molten alloy from a quartz tube nozzle with an argon gas pressure of 1.6 atmospheres between two rolls rotating at a high speed of 4500 rpm. Width 2
mm thickness 40μm, length 10m
_{Co 0 . 94 Fe 0 . _ _} After applying and quenching, 16 coils are used to apply a DC magnetic field.
Roll it up and store it in vacuum at 100℃, 150℃, 250℃,
The furnace was cooled from 300℃ and 350℃ to room temperature with a DC magnetic field of 50e applied. The cooling rate of the furnace was approximately 60°C/hour. The Curie temperature of this amorphous alloy was measured and was 350°C. The effective magnetic permeability and maximum magnetic permeability were measured and the results are shown in Table 1. As is clear from Table 1, the maximum magnetic permeability is improved by cooling the amorphous alloy from below the crystallization temperature to room temperature in a DC magnetic field, but the effective magnetic permeability is within a specific temperature range below the crystallization temperature. It is clear that this can be improved by only heat treatment.

【table】

[Table] (Example 2) Conducted on a (Co ₀ . ₈₈ Fe ₀ . ₀₆ Ni ₀ . ₀₃ Nb ₀ . ₀₃ ) ₇₅ Si ₁₀ B ₁₅ amorphous alloy ribbon obtained by the same method as in Example 1. The implementation was carried out in the same manner as in Example 1. The results are shown in FIG. The Curie point of this amorphous alloy was 330°C. In FIG. 1, Nb is used as an example of M, but similar trends were observed when other elements were used as M. The results are shown in Table 2. As a result, it is clear that the effective magnetic permeability is significantly improved only when furnace cooling is performed from the range of 120 to 270°C to room temperature.

【table】

[Table] (Example 3) Conducted on (Co ₀ . ₈₄ Fe ₀ . ₁₀ Ni ₀ . ₀₃ Nb ₀ . ₀₃ ) ₇₅ Si ₁₀ B ₁₅ amorphous alloy ribbon obtained by the same method as in Example 1. The experiment was carried out in the same manner as in Example 1. The results are shown in Figure 2. As shown in the above four examples, the effective magnetic permeability of Co-based amorphous alloys is significantly improved by furnace cooling in a magnetic field, and the optimum starting temperature for furnace cooling in a magnetic field varies somewhat depending on the component composition. Although different, it was shown to be within the temperature range between 120°C and 270°C. As described above, by using the method according to the present invention, a high permeability amorphous alloy with excellent effective magnetic permeability can be obtained, which is extremely effective for magnetic devices such as magnetic heads and minute current sensors.

[Brief explanation of the drawing]

Figure 1 is a curve diagram showing the relationship between the furnace cooling start temperature in a magnetic field and the effective magnetic permeability at 1 KHz for the (Co ₀ . ₈₈ Fe ₀ . ₀₆ Ni ₀ . ₀₃ ) ₇₅ Si ₁₀ B ₁₅ amorphous alloy; The figure is _{a curve diagram} showing the relationship between _{the furnace} cooling _{start temperature} in a magnetic field and the effective magnetic permeability at _1KHz for the ( _{Co0.84Fe0.10Ni0.03Nb0.03} ) _{75Si10B15 amorphous} alloy. be.

Claims (1)

[Claims] 1 (Co _1-ab Fe _a M _b ) _{1- x} ,Cr,Mo,
W a = 0.04 to 0.11 b ≦ 0.1 x = 0.20 to 0.28] in a DC magnetic field.
A method for improving the effective magnetic permeability of a Co-based amorphous alloy, characterized by furnace cooling from a range of 120 to 270°C to room temperature. 2. A method for improving the effective magnetic permeability of a Co-based amorphous alloy according to claim 1, which comprises cooling in a furnace from a range exceeding 150°C and below 270°C to room temperature. 3. Co according to claim 1, characterized in that it is furnace cooled from a range of 200°C to 250°C to room temperature.
A method for improving the effective magnetic permeability of amorphous alloys. 4 M is Nb, V, Ta, Ti, Zr, Cr, Mo and W
2. A method for improving the effective magnetic permeability of a Co-based amorphous alloy according to claim 1, wherein the Co-based amorphous alloy is at least one selected from the following. 5 M is Nb, V, Ta, Ti, Zr, Cr, Mo and W
2. A method for improving the effective magnetic permeability of a Co-based amorphous alloy according to claim 1, characterized in that at least one selected from the following is used: and Ni.