JP3389972B2 - Nanocrystalline alloy ribbon with improved asymmetry of BH loop and method for producing magnetic core and nanocrystalline alloy ribbon - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of nanocrystalline alloy ribbons and magnetic cores and nanocrystalline alloy ribbons having improved asymmetry of BH loops used in transformers, choke coils, saturable reactors and the like. Regarding the method.

[0002]

2. Description of the Related Art Since nanocrystalline alloys have excellent soft magnetic properties, common mode choke coils, high frequency transformers,
Used in earth leakage alarms and magnetic switch cores. A typical composition system is an Fe-Cu-M-Si-B system alloy described in Japanese Patent Publication No. 4393/1992. These nanocrystalline alloys are usually produced by quenching an alloy having the above composition from a liquid phase or a gas phase to form an amorphous alloy, and then microcrystallizing the amorphous alloy by heat treatment. Known methods for quenching from the liquid phase include a single roll method, a twin roll method, a centrifugal quenching method, a rotating submerged spinning method, an atomizing method and a cavitation method. Further, as a method of quenching from the gas phase, a sputtering method, a vapor deposition method, an ion plating method and the like are known. Nanocrystalline alloy is a microcrystallized amorphous alloy produced by these methods, has almost no thermal instability as seen in amorphous alloys, high saturation magnetic flux density,
It exhibits low magnetostriction and excellent soft magnetic properties.

[0003]

However, as a result of intensive studies, narrow-width materials produced by the liquid quenching method in nanocrystal alloys do not cause much problems, but wide-width materials and thick-material materials are used in mass production bases. It has been found that there is a problem that the BH curve becomes asymmetric when manufactured. This tendency is remarkable in a material having a large amount of impurities such as Al and a composition having a high saturation magnetic flux density. When a material having such an asymmetric BH loop is used in a magnetic core and incorporated in a circuit, the same operation as in the case where the magnetic core exhibits a symmetric BH loop is not performed. Is not preferable because it does not work well or the circuit becomes unstable. The present invention is a B-H rule
It is an object of the present invention to provide a nanocrystalline alloy ribbon having improved asymmetry of a magnetic field, a magnetic core, and a method for producing a nanocrystalline alloy ribbon.

[0004]

The present inventors to solve the above problems SUMMARY OF THE INVENTION, the composition formula (Fe _1-a M _{a)
100-xyz-α - β - γ} A _x Si _y B _{z M'α} M '' _β X _γ (at%)
(However, M is Co and / or Ni, A is Cu,
At least one element selected from Au, M ′ is Nb,
At least one element selected from the group consisting of Mo, Ta, Ti, Zr, Hf, V, and W, M ″ is Cr, M
n, Al, platinum group element, at least one element selected from the group consisting of Sc, Zn, Re and Ag, X is C, G
It is at least one element selected from the group consisting of e, P, Ga, N and O, and a, x, y, z, α, β and γ are each 0
≤a ≤0.5,0.1 ≤x ≤3,0 ≤y ≤17,0 ≤z ≤10,0.1 ≤α ≤20,0
≦ β ≦ 20, 0 ≦ γ ≦ 20 are satisfied. ) Is a nanocrystalline alloy ribbon having a composition of at least 50% of which is composed of crystal grains having a grain size of 50 nm or less, and a Sn content of 0.
Containing 01 to 1 wt%, concentration distribution measurement by AES method
Has a concentration of at least Sn from the surface to 0.1μm or less in the region of one side region of high formation in, the Sn concentrated
The peak value of the intensity corresponding to Sn in the high frequency region is Sn.
3 times or more of the Sn concentration stable part where the concentration of Sn is almost constant
Upper magnetic core and using a nanocrystalline alloy ribbon and which is represented by the composition formula _{(Fe 1-a M a)} 100-xyz-α - β - γ A x Si y B
_z M ′ _α M ″ _β X _γ (at%) (where M is Co and / or Ni, A is at least one element selected from Cu and Au, and M ′ is Nb, Mo, Ta, Ti , Zr, H
at least one element selected from the group consisting of f, V, and W, M ″ is Cr, Mn, Al, a platinum group element, S
at least one element selected from the group consisting of c, Zn, Re and Ag, X is at least one element selected from the group consisting of C, Ge, P, Ga, N and O, and a, x, y,
z, α, β and γ are 0 ≦ a ≦ 0.5, 0.1 ≦ x ≦ 3, 0 ≦ y ≦ 1 respectively
7,0 ≦ z ≦ 10, 0.1 ≦ α ≦ 20, 0 ≦ β ≦ 20, 0 ≦ γ ≦ 20 are satisfied. ) , A nanocrystalline alloy ribbon having at least 50% of its structure composed of crystal grains having a grain size of 50 nm or less, S in an amount of 0.005 to 0.05 wt% , A
1 to 0.001 to 0.3 wt%, and according to the AES method
When measuring the concentration distribution,
A region having a high S concentration is formed within the region of 1 μm or less .
Ri, Pi of intensity corresponding to the S of the high realm concentrations of S - click value
However, 3 of the S concentration stabilizing part where the S concentration is almost constant
The inventors have found that the asymmetry of the BH loop is improved in the nano-crystalline alloy ribbon which is more than double and the magnetic core using the ribbon, and the present invention has been made. In the present invention, the asymmetry of the BH loop will be represented by the shift Hs of the DC BH loop. Hs was defined as follows using Hc1 and Hc2 shown in FIG. _{Hs = (Hc 1 + Hc 2} ) / 2 However, if the position of Hc _1, Hc ₂ is the right side with respect to the B-axis and negative if the value of Hc _1, Hc ₂ positive, left. The maximum applied magnetic field at the time of measurement was 8 A / m (0.1 Oe). Furthermore, B-H Le - coercive force Hc in the case flops asymmetric is defined as _{Hc = (Hc 1 -Hc 2)} / 2. It means that the larger the Hs, the larger the asymmetry of the BH loop.

In the present invention, the formation of a region having a high Sn or S concentration is an important point for improving the asymmetry of the BH loop. It is believed that the excellent soft magnetic properties of nanocrystalline alloys are obtained because of the formation of uniform and fine crystal grains, but the formation of coarser crystal grains than the inside on the surface is preferable because it leads to deterioration of soft magnetism. Not only that, but the BH loop becomes asymmetric, which is not preferable. It is considered that such coarse crystal grains are related to the concentration variation of the amorphizing element near the surface.
Is added to form a region having a high Sn or S concentration in the vicinity of the surface, the change in concentration of the amorphous forming element such as Si near the surface is reduced, and coarse crystal grains are prevented from being formed. Seem. The coarse crystal grains are formed during ribbon production or heat treatment, and the crystal grains are often in the bccFe phase, and the crystal grains may be oriented. It is considered that the formation of such crystal grains has some relation to the oxide formation on the ribbon surface.

In the present invention, the effect of improving the asymmetry is great especially when the intensity peak value in the region where the Sn or S concentration is high is 3 times or more the value of the Sn or S concentration stabilizing portion.
Here, the Sn or S concentration stabilizing portion refers to a portion where the Sn or S concentration shows a substantially constant value, and as shown in Example 1 described later, the concentration from the ribbon surface by the AES method (Auger electron spectroscopy). It can be observed by distribution measurement. Furthermore, the asymmetry improving effect of the BH loop is such that Al is 0.0
It is remarkable in the alloy system containing 001 wt% or more and 0.3 wt% or less. Al easily enters as an impurity when an inexpensive raw material is used, and the present invention exerts a remarkable effect particularly when an inexpensive raw material is used. Representative alloy system according to the present invention, For example other Fe-Cu-Nb-Si- B alloy and Fe-Cu-Zr-B based alloy and the like are known.

The heat treatment of the alloy of the present invention can be performed in a magnetic field. The effect of the present invention is particularly remarkable when heat treatment is performed in a magnetic field in the magnetic path direction of the magnetic core. Further, in this case, the alloy of the present invention and the magnetic core also have the effect of easily improving the squareness ratio of the BH curve. Another aspect of the present invention is a process of obtaining an amorphous alloy ribbon by a super-quenching method, and heat-treating the ribbon, the crystal grains having an average crystal grain size of 50 nm or less occupy at least 50% of the structure, and at least one surface To 0.1 μm or less, a method for producing the above nanocrystalline alloy ribbon, comprising a step of forming a Sn or / and S-rich region. 100 before heat treatment to form grains
In the case of including a step of holding at a temperature of ℃ to 350 ℃ for 10 minutes to 1000 hours, it is easy to obtain the alloy of the present invention, it is possible to reduce the characteristic variation due to the fluctuation of the ribbon manufacturing conditions, and the effect of improving the asymmetry. Can be increased.

The heat treatment is usually performed in an atmosphere of an inert gas such as Ar, He or nitrogen. However, the gas usually contains oxygen, and the heat treatment is performed in the presence of oxygen. Further, the effects of the present invention can be obtained even in the air or an atmosphere containing a large amount of oxygen.

[0009]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited thereto. (Example 1) Compositional formula Fe _bal. Cu ₁ Nb ₂ Si _12.2 B _9.1
(at%) of the master alloy and the alloy of the above composition with Sn of 0.1,
A master alloy containing 0.5 wt% and a master alloy containing no Sn were prepared by high frequency melting. Then, it was rapidly cooled by a single roll method using Cu-Be roll to prepare an amorphous alloy having a width of 30 mm. Next, use this alloy ribbon with an outer diameter of 35 mm and an inner diameter of 35
A toroidal coil having a diameter of 0.1 mm was wound to produce a wound magnetic core. Next, this alloy magnetic core was heat-treated at 530 ° C. for 1 hour in a nitrogen gas atmosphere. The DC BH curve of each magnetic core is measured, and the surface of the ribbon used for each magnetic core is AES.
Was analyzed by. The shift amount H _s of the B-H curve is 0.7 A / m when Sn is not added, and 0.1 when Sn 0.1 wt% is added.
A / m and Sn 0.5 wt% is 0 A / m and Sn
In the alloy in which a region having a high Sn concentration was formed in a region of 0.1 μm or less from the surface after the addition, the shift amount of the BH curve was small and the asymmetry was improved. FIG. 2 shows the analysis result by the AES method. A region having a high Sn concentration is formed in a region of 0.1 μm or less from the surface. The peak value is three times or more that of the thin band thickness Sn concentration stable portion, that is, the portion where the Sn concentration is substantially constant. In the sample in which the region having a high Sn concentration is formed in the region of 0.1 μm or less from the surface, the asymmetry is small and a preferable result is obtained. On the other hand, when Sn is not contained, the BH loop has a large asymmetry.

(Example 2) Compositional formula Fe _bal. Cu ₁ Nb ₂ S
i _10.8 B _9.1 (at%) alloy with 0.005, 0.0
1, 0.05, 0.1, 0.3, 0.5, 1, 1.5 wt%
The added mother alloy was produced by high frequency melting. Then Cu-
It was rapidly cooled by a single roll method using Be roll to prepare a 30 mm wide amorphous alloy. Next, use this alloy ribbon with an outer diameter of 35 m.
m and an inner diameter of 35 mm were wound into a toroidal shape to prepare a wound magnetic core. Next, this alloy magnetic core is placed in a nitrogen gas atmosphere at 530 °
Was heat-treated for 1 hour. DC BH of each magnetic core
The curve was measured, and the surface of the ribbon used for each magnetic core was analyzed by the AES method. Table 1 shows the segregation state of Sn on the free surface and the shift amount H _s of the BH _loop . A region having a high Sn concentration is formed in a region of 0.1 μm or less from the surface. Moreover, the peak value is three times or more that of the Sn concentration stable portion. If the Sn content is less than 0.01 wt%, the B-H loop has a large asymmetry. On the other hand, when the Sn content exceeds 1 wt%, the ribbon becomes brittle when manufactured by the single roll method, and continuous ribbon production cannot be performed. On the other hand, when Sn is in the range of 0.01 to 1 wt%, the asymmetry is small and favorable results are obtained.

[0011]

[Table 1]

Reference Example An alloy having the composition formula Fe _bal. Cu ₁ Nb ₂ Si ₁₀ B _9.5 (at%) with S added to 0.0005, 0.001, 0.00
A master alloy containing 5, 0.01, 0.03, 0.05, and 0.1 wt% was prepared by high frequency melting. Next, Cu-Be
It was rapidly cooled by a single roll method using a roll to prepare an amorphous alloy with a width of 50 mm. Next, this alloy ribbon was wound into a toroidal shape having an outer diameter of 35 mm and an inner diameter of 35 mm to produce a wound magnetic core.
Next, this alloy magnetic core was heat-treated at 530 ° C. for 1 hour in a nitrogen gas atmosphere. The DC BH curve of each magnetic core was measured, and the surface of the ribbon used for each magnetic core was AE.
It analyzed by the S method. Table 2 shows the segregation state of S on the free surface and the shift amount H _s of the BH _loop . A region having a high S concentration is formed in a region of 0.1 μm or less from the surface. Further, the peak value is three times or more that of the S concentration stable portion. B in alloy ribbons with an S content of less than 0.001 wt%
The asymmetry of the -H loop is large. On the other hand, the S content is 0.
If it exceeds 05 wt%, the ribbon becomes brittle when manufactured by the single roll method, and continuous ribbon production is difficult. On the other hand, when S is in the range of 0.001 to 0.05 wt% and a high S concentration region is formed in the region of 0.1 μm or less from the ribbon surface, H _s is small (the asymmetry is small. ) Good results have been obtained.

[0013]

[Table 2]

(Example 3 ) Sn or S was added to a mother alloy having the composition shown in Table 3, and an amorphous alloy ribbon having a width of 50 mm was produced by a single roll method. Next, this ribbon was wound around an outer diameter of 60 mm and an inner diameter of 40 mm, and heat-treated while applying a magnetic field of 5 Oe in the magnetic path direction to produce a magnetic core made of the nanocrystalline ribbon of the present invention and the reference example . When Sn or S is added to the master alloy having the composition shown in Table 3 and a region with a high Sn or S concentration is formed within a region of 0.5 μm or less from the surface of one side, and when Sn or S is not added The shift amount H _s of the BH _loop is shown.
When a region having a high Sn or S concentration is formed, the BH loop shift amount is small. In addition, Al, Zr, Ti
At least one element selected from 0.0001 wt
It can be seen that the effect of reducing the shift amount of Sn or S addition is particularly large when the content is from 0.3% to 0.3% by weight.

[0015]

[Table 3]

Example 4 Sn or S was added to a mother alloy having the composition shown in Table 4, and an amorphous alloy ribbon having a width of 50 mm was produced by a single roll method. Next, this thin strip was wound around an outer diameter of 60 mm and an inner diameter of 40 mm, and heat-treated in the atmosphere at the temperature and time shown in Table 4.
Next, while applying a magnetic field of 5 Oe in the magnetic path direction, heat treatment was performed at a temperature equal to or higher than the crystallization temperature to produce a magnetic core made of the nanocrystalline ribbon of the present invention and the reference example . When Sn or S was added to the master alloy having the composition shown in Table 4 and a region having a high Sn or S concentration was formed within a region of 0.1 μm or less from the surface on one side, and when Sn or S was not added The shift amount H _s of the BH _loop is shown. When a region having a high Sn or S concentration is formed, the shift amount H _s of the BH _loop is small,
The symmetry of the BH curve is good.

[0017]

[Table 4]

[0018]

According to the present invention, it is possible to provide a nanocrystalline alloy ribbon having improved BH loop asymmetry, a method for producing a magnetic core and a nanocrystalline alloy ribbon, and the effect is remarkable. There is.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a BH _loop shift amount H _s .

FIG. 2 is a diagram showing concentration distributions of main elements in the thickness direction from the free surface of the nanocrystalline alloy ribbon of the present invention and the comparative example.

Continuation of front page (56) Reference JP-A-3-53048 (JP, A) JP-A-3-197651 (JP, A) JP-A-5-78796 (JP, A) JP-A-5-117818 (JP , A) JP 4-329846 (JP, A) JP 1-287250 (JP, A) JP 5-222494 (JP, A) JP 6-287721 (JP, A) JP 6-220592 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C22C 38/00-45/10 H01F 1/16

Claims (6)

(57) [Claims] 1. A composition formula _{(Fe 1-a M a)} 100-xyz-α - β - γ
A _x Si _y B _{z M'α} M '' _β X _γ (at%) (where M is Co and / or Ni, A is Cu,
At least one element selected from Au, M ′ is Nb,
At least one element selected from the group consisting of Mo, Ta, Ti, Zr, Hf, V, and W, M ″ is Cr, M
n, Al, platinum group element, at least one element selected from the group consisting of Sc, Zn, Re and Ag, X is C, G
It is at least one element selected from the group consisting of e, P, Ga, N and O, and a, x, y, z, α, β and γ are each 0
≤a ≤0.5,0.1 ≤x ≤3,0 ≤y ≤17,0 ≤z ≤10,0.1 ≤α ≤20,0
≦ β ≦ 20, 0 ≦ γ ≦ 20 are satisfied. ) Is a nanocrystalline alloy ribbon having a composition of at least 50% of which is composed of crystal grains having a grain size of 50 nm or less, and a Sn content of 0.
Containing 01 to 1 wt%, concentration distribution measurement by AES method
Has a concentration of at least Sn from the surface to 0.1μm or less in the region of one side region of high formation in, the Sn concentrated
The peak value of the intensity corresponding to Sn in the high frequency region is Sn.
3 times or more of the Sn concentration stable part where the concentration of Sn is almost constant
A nanocrystalline alloy ribbon having improved BH loop asymmetry characterized by the above . 2. A composition formula _{(Fe 1-a M a)} 100-xyz-α - β - γ
A _x Si _y B _{z M'α} M '' _β X _γ (at%) (where M is Co and / or Ni, A is Cu,
At least one element selected from Au, M ′ is Nb,
At least one element selected from the group consisting of Mo, Ta, Ti, Zr, Hf, V, and W, M ″ is Cr, M
n, Al, platinum group element, at least one element selected from the group consisting of Sc, Zn, Re and Ag, X is C, G
It is at least one element selected from the group consisting of e, P, Ga, N and O, and a, x, y, z, α, β and γ are each 0
≤a ≤0.5,0.1 ≤x ≤3,0 ≤y ≤17,0 ≤z ≤10,0.1 ≤α ≤20,0
≦ β ≦ 20, 0 ≦ γ ≦ 20 are satisfied. ), A nanocrystalline alloy ribbon having a composition of at least 50% of which has a grain size of 50 nm or less, and S is 0.0
05 to 0.05 wt% , Al from 0.0001 to 0.3
containing wt%, even less <br/> without the concentration distribution measurement by AES method has a region with high concentration of S is formed from one side surface to 0.1μm or less in area, high realm concentrations of S of
The peak value of the intensity corresponding to S is such that the concentration of S is almost constant.
A nanocrystalline alloy ribbon having improved BH loop asymmetry, which is at least three times as large as the S concentration stable portion . 3. Al of 0.0001 wt% or more and 0.3 wt
% Or less, The nanocrystalline alloy ribbon according to claim 1 . 4. A magnetic core comprising the nanocrystalline alloy ribbon according to any one of claims 1 to 3 . 5. A step of obtaining an amorphous alloy ribbon by a super-quenching method, and a heat treatment of the ribbon to occupy at least 50% of the structure with crystal grains having an average crystal grain size of 50 nm or less, and 0 from at least one surface. Sn or / in the area of less than 0.1 μm
The method for producing a nanocrystalline alloy ribbon according to any one of claims 1 to 4 , comprising the step of forming a region having a high S concentration. 6. 100 ° C. before heat treatment to form grains
The method for producing a nanocrystalline alloy ribbon according to claim 5 , wherein the heat treatment is performed by holding at a temperature of 1 to 400 ° C. for 10 minutes to 1000 hours.