JPH0526861B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for modifying magnetic properties to obtain an amorphous alloy having low magnetic loss and high squareness. [Conventional technology] Deltamax (50% Ni alloy) has conventionally been used as a crystalline soft magnetic material with low magnetic loss and high angularity.
and supermalloy (78% Ni alloy), each of which is used in magnetic amplifier cores depending on its characteristics. [Problems to be solved by the invention] Although these conventional magnetic materials are used to manufacture thin plates,
Since it requires many steps such as vacuum melting, ingot making, forging, hot rolling, intermediate annealing, and cold rolling, its production requires a large amount of fuel and electricity. As a result, the product ultimately becomes expensive compared to the cost of raw materials. In addition, due to recent advances in electronic equipment, the conditions for using magnetic materials as component materials have become high frequency ranges of 100 to several hundred kHz, and drive amplitudes have also increased. power loss,
It is becoming difficult to deal with this in terms of squareness. An object of the present invention is to provide a method for modifying magnetic properties to obtain an amorphous alloy having low magnetic loss and high squareness, without the above-mentioned drawbacks of conventionally used magnetic materials. [Means for solving the problem] According to the present invention, in terms of atomic ratio, Fe3 to 12%,
Ni40% or less (not including 0%), Si20% or less (0%
), B5 to 20%, but containing Si + B20 to 28%, and the remainder substantially Co, in an atmosphere with an oxygen concentration of 20% or more, at a temperature below the crystallization temperature of the alloy, and at a temperature below the crystallization temperature of the alloy A method for producing an amorphous alloy with low magnetic loss and high squareness is obtained, which is characterized by maintaining the temperature at a temperature higher than that temperature, subsequently applying a magnetic field of 10 Oe or higher, and cooling at a rate of 5° C./min. Furthermore, according to the present invention, in atomic ratio, Fe3~12
%, Ni 40% or less (not including 0%), Si 20% or less (not including 0%), B5 to 20%, but Si + B20 to 28%
In addition, Cr, Mn, Mo, Zr, Ti, V, Nb,
An amorphous amorphous alloy containing 10% or less of at least one selected from Ta, W, and Cu, with the remainder substantially consisting of Co, is heated below the crystallization temperature of the alloy in an atmosphere with an oxygen concentration of 20% or more. In addition, there is obtained a method for producing an amorphous amorphous alloy having low magnetic loss and high squareness, which is characterized by maintaining the temperature at the Curie temperature or higher, subsequently applying a magnetic field of 10 Oe or higher, and cooling at a rate of 5° C./min. . Next, the reason for limiting the content of each component in the amorphous alloy in the magnetic property modification method of the present invention will be described. B is an element that promotes amorphous formation, but if it is less than 5% or exceeds 20%, it becomes difficult to manufacture amorphous alloy thin sheets and the alloy becomes brittle, so it should be reduced to 5 to 20%. Must be within the range. Si is an element that supports the amorphousization of the alloy structure and reduces magnetic loss, but if it exceeds 20%, the magnetic loss will not decrease much and it will only significantly lower the Curie temperature of the alloy, so it should not be more than 20%. It is necessary to Also
If the total Si + B content is less than 20%, the heat treatment effect of the present invention will not work effectively, and if it is more than 28%, an alloy thin plate with high squareness will not be obtained.
Must be within the range of ~28%. Fe is 3%
If it is less than 12% or more than 12%, magnetostriction increases and low magnetic loss cannot be obtained even by using the heat treatment method of the present invention, so it is necessary to keep it within the range of 3 to 12%. Ni widens the range of zero magnetostriction,
It is an element that reduces magnetic loss, but if it exceeds 40%, it lowers the saturation magnetic flux density and the Curie temperature of the alloy approaches room temperature, reducing its utility as a practical material by half, so it must be kept below 40%.
Cr, Mn, Mo, Zr, Ti, V, Nb, Ta, W, and Cu are elements that reduce magnetic loss and improve thermal stability, but if they exceed 10%, they significantly reduce the saturation magnetic flux density. Since its economic value as a practical material is halved, it must be kept at 10% or less. [Example] The following is a description based on an example. First, a method for measuring the characteristics shown below will be explained. The crystallization temperature was measured using a differential thermal analyzer. The Kyrie temperature was determined from the temperature change in effective magnetic permeability at 1kHz and 10mOe. The magnetic loss is U
Measured using a function meter under the conditions of a frequency of 200 kHz and a magnetic flux density of 5 kG, and the measurement core dimensions are height 5 mm and inner diameter 15 mm.
The core was wound with an outer diameter of 19 mm. Table 1 shows the composition, crystallization temperature, and Curie temperature of the amorphous amorphous alloy used in the present invention.

[Table] In general, amorphous alloys change to crystalline state at a certain temperature depending on their composition. Similarly, the amorphous alloy used in the present invention must be heat-treated at a temperature below the crystallization temperature shown in Table 1. In addition, as shown in the previously filed method for manufacturing an amorphous alloy with high effective magnetic permeability (Japanese Patent Application No. 116579/1989, ie, Japanese Patent Application Laid-Open No. 43028/1989), magnetic loss can be reduced. In order to achieve this, cooling from a temperature below the crystallization temperature and above the Curie temperature is necessary, regardless of the preheat treatment. Therefore, in the present invention, annealing is also performed under these conditions. Table 2 shows amorphous amorphous alloys having the compositions shown in Table 1 in air, nitrogen, and hydrogen atmospheres.
This figure shows the magnetic loss and squareness ratio of an alloy that was heated at 440°C for 20 minutes and then cooled at a rate of 5°C for 1 minute while applying an alternating current magnetic field of 10 Oe and 50 Hz.

[Table] As is clear from this table, the magnetic loss of the amorphous amorphous alloy used in the present invention depends on the heat treatment atmosphere, and heat treatment in an oxidizing atmosphere significantly improves the magnetic loss compared to heat treatment in other atmospheres. I understand. Table 3 shows changes in magnetic loss when the mixing ratio of nitrogen and oxygen is changed in order to show the effect of an oxidizing atmosphere on magnetic loss in more detail.

[Table] The composition of the amorphous amorphous alloy used in this experiment is B in Table 1. The annealing conditions were as follows: heating at 440° C. for 20 minutes, followed by cooling at a rate of 5° C. for 1 minute while applying an AC magnetic field of 10 Oe and 50 Hz. As is clear from this table, the oxygen concentration is 70%
Magnetic loss decreases as the amount of oxygen increases in the range up to 100%, and on the contrary, annealing in pure oxygen is worse than annealing in air. However, the magnetic loss is improved to about 1/2 compared to annealing in pure nitrogen. This shows that annealing in an atmosphere with a higher oxygen content than the atmospheric oxygen concentration significantly improves magnetic loss compared to annealing in a non-oxidizing atmosphere. Next, FIG. 1 shows the relationship between relative magnetostriction and magnetic loss determined by applying stress to a ribbon-shaped sample. In this figure, Bm(σ≠0)/Bm(σ=
0) < 1 corresponds to negative saturation magnetostriction, and Bm(σ≠
0)/Bm (σ=0)>1 corresponds to positive saturation magnetostriction. As is clear from this figure, when heat treatment is performed in a non-oxidizing atmosphere such as nitrogen or hydrogen, the composition with the minimum magnetic loss corresponds to a composition with approximately zero magnetostriction, but when heat treatment is performed in an oxidizing atmosphere, It can be seen that when the heat treatment is carried out, the composition with the minimum magnetic loss shifts to the negative saturation magnetostriction side, and the heat treatment in an oxidizing atmosphere results in a lower magnetic loss. Next, in order to clearly demonstrate the effect of the annealing method of the present invention,
Compare with magnetic properties obtained by annealing other than the present invention. Table 4 shows the cases in which the temperature was maintained at 440℃ for 20 minutes in the air, then cooled at a rate of 5℃ for 1 minute with a magnetic field of 10Oe and 50Hz applied, and the case where the temperature was cooled at a rate of 5℃ for 1 minute without applying a magnetic field.
Comparison of magnetic properties when cooled at a rate of ℃ is shown.

〔Effect of the invention〕

As explained above, according to the present invention, an amorphous alloy having low magnetic loss and high squareness can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between magnetic loss and relative magnetostriction determined by stress application when the amorphous alloy used in the present invention is heat treated in air, nitrogen, and hydrogen atmospheres.

Claims (1)

[Claims] 1. In terms of atomic ratio, Fe3 to 12%, Ni 40% or less (0%
), Si20% or less (not including 0%), B5~
20%, but includes Si+B20~28%, the remainder is essentially
An amorphous amorphous alloy made of Co with an oxygen concentration of 20
Magnetic loss characterized by maintaining the alloy at a temperature below the crystallization temperature and above the Curie temperature in an atmosphere of 10% or more, and then cooling at a rate of 5°C/min by applying a magnetic field of 10Oe or more. A method for producing an amorphous amorphous alloy having a small squareness and high squareness. 2 Atomic ratio Fe3~12%, Ni40% or less (not including 0%), Si20% or less (not including 0%), B5~20
%, however, Si + B should be 20 to 28%, and Cr, Mn,
An amorphous amorphous alloy containing 10% or less of at least one selected from Mo, Zr, Ti, V, Nb, Ta, W, and Cu, with the remainder essentially Co, in an atmosphere with an oxygen concentration of 20% or more. The temperature was maintained at a temperature below the crystallization temperature of the alloy and above the Curie temperature, and then a magnetic field of 10 Oe or more was applied to heat the alloy at 5°C/
1. A method for producing an amorphous amorphous alloy having low magnetic loss and high squareness, characterized by cooling at a rate of 100%.