JPH06158239A - Fe base soft magnetic alloy and its production - Google Patents

Abstract

PURPOSE:To produce an Fe base soft magnetic alloy low in saturated magnetostriction and iron loss at a low cost by subjecting a rapidly cooled allay having a specified compsn. constituted of Fe and Co or Ni, Al, Nb or the like, Si or the like, B, P and C to specified heat treatment. CONSTITUTION:A rapidly cooled allay having a compsn. expressed by (Fe1-xAx)100-a-b-c-d-e-fAlaMbM'cBdPeCf (in the formula, A denotes Co and/or Ni, M denotes Nb, Mo, W, Ta, Zr, Hf, Ti, V, Cr, Mn, Y and Ce, M' denotes Si, Ga, Ge, Ru, Sn, Sb and Pdm and 0<=X<=0.2, 2<a<=15 atomic %, 3<=b<=20%, 0<=C<=6%, 1<=d<=9%, 2<e<=9%, 0.1<=f<=5% and 1<=e/f<=40) is produced by a quenching method, a thin film forming method or a powder forming method. After that, this rapidly cooled allay is held at 200 to 800 deg.C within 24hr and is subjected to heat treatment. In this way, the Fe base soft magnetic alloy in which >=30% of the structure is constituted of fine crystalline grains with >=1000Angstrom average grain size of bcc solid solution essentially consisting of iron and excellent in soft magnetic properties can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Fe-based soft magnetic alloy, and more particularly to an Fe-based soft magnetic alloy having good soft magnetic properties and a method for producing the same.

[0002]

2. Description of the Related Art In recent years,
As a magnetic core material for a magnetic head, a high frequency transformer, a saturable reactor, a choke coil, etc., an Fe-based amorphous magnetic alloy having a high saturation magnetic flux density is widely known. However, although Fe-based amorphous magnetic alloys are cheaper than Co-based alloys, they generally have large core loss and low magnetic permeability. Further, since the saturation magnetostriction is large, it cannot be said that the magnetic characteristics are sufficient.

The present invention provides a novel Fe-based soft magnetic alloy which is a soft magnetic material that replaces the conventional Fe-based amorphous magnetism, has a small saturation magnetostriction and iron loss, and is low in cost. The purpose is to provide.

[0004]

In order to achieve such an object, the present inventor has conducted earnest research on an Fe-based soft magnetic alloy. As a result, the Fe-B type Fe-based soft magnetic alloy contains Al and a specific element M, In particular, when Nb is added, excellent soft magnetic characteristics are exhibited, for example, saturation magnetostriction is low, and such Fe
It was found that when phosphorus (P) and carbon (C) are added to a -B-Al-M Fe-based soft magnetic alloy, excellent soft magnetic characteristics are exhibited, and the present invention has been completed.

That is, the Fe-based soft magnetic alloy of the present invention is (F
e_1-xA_x)_100-abcdefAl_aM _bM ’_cB_dP_eC
_f(In the formula, A is Co and / or Ni, M is Nb, Mo,
W, Ta, Zr, Hf, Ti, V, Cr, Mn, Y, C
represents one or more elements selected from e, M '
Is selected from Si, Ga, Ge, Ru, Sn, Sb, Pd
Represents one or more elements. x is 0 ≦ x ≦
0.2, and a, b, c, d, e, f represent atomic%
, 2 <a ≦ 15, 3 ≦ b ≦ 20, 0 ≦ c ≦
6, 1 ≦ d ≦ 9, 2 <e ≦ 9, 0.1 ≦ f ≦ 5
However, the composition ratio e / f (atomic ratio) of P and C is 1 ≦ e / f ≦
40 is satisfied).
In addition, at least 30% or more of the structure is formed by fine crystal grains.
It is preferable that the crystal grains are mainly iron.
It is composed of a bcc solid solution mainly composed of.

The alloy structure of the Fe-based soft magnetic alloy of the present invention immediately after quenching is preferably in an amorphous state, but if it is within a range where soft magnetic characteristics can be obtained after heat treatment, even if some crystalline materials are mixed. Good. In the Fe-based soft magnetic alloy of the present invention, Fe can be replaced with A (Co and / or Ni) in the range of x of 0 to 0.2. A is a solid solution in a bcc crystal mainly composed of Fe generated during heat treatment, and particularly Co is saturation magnetization,
Ni contributes to the improvement of the magnetocrystalline anisotropy constant. In the present invention, when the content of A (the ratio of A when the total of Fe and A is 1) x is more than 0.2, the generated phases other than the bcc structure are observed and the soft magnetic characteristics deteriorate. Therefore, the content x of A is preferably 0.2 or less. More preferably, it is 0.1 or less.

Al is an essential element of the alloy of the present invention.
Addition of a specific amount of 1 (more than 2 atomic% and 15 atomic% or less) inhibits the crystallization temperature (Tx1) and soft magnetism of the soft magnetic crystal (Fe-based bcc solid solution) with small magnetocrystalline anisotropy. The temperature difference (ΔT) from the crystallization temperature (Tx2) of the crystal (for example, Fe-B type crystal) to be formed can be increased,
In addition to suppressing generation of Fe-B type crystals during heat treatment,
The soft magnetic characteristics can be derived by heat treatment at a relatively low temperature. Similar to Ni (Co), Al has a negative mutual parameter with Fe.
To form a solid solution in the solid solution, that is, in the form of being substituted at the position of the Fe atom in the α-Fe crystal structure to stabilize the bcc crystal. Further, Al is presumed to refine the precipitated crystal grains generated by the heat treatment. From the above, it is considered that the addition of Al in the present alloy system selectively produces fine crystal grains having a small magnetocrystalline anisotropy, and thereby excellent soft magnetic characteristics are exhibited.

In the present invention, the Al content a is more than 2 atomic% and 15 atomic%, preferably 2.5 to 10 atomic%.
More preferably, it is 3 to 6 atomic%. In the range of 3 to 6 atomic%, an alloy having a particularly small iron loss can be obtained. The element M in the present invention is Nb, Mo, W, Ta, Z.
Suppress precipitation of Fe-B or Fe-P-based crystals, which inhibits expression of soft magnetism, with one or more elements selected from r, Hf, Ti, V, Cr, Mn, Y, and Ce, or It is presumed that it has the effect of moving the precipitation start temperature to a higher temperature. Furthermore, the addition of the element M has the effect of improving not only the crystal grain refinement but also the amorphous forming ability. Further, Nb is preferable as M.

The content b of the element M in the present invention is 3 atom% to 20 atom%, preferably 3 to 15 atom%, more preferably 5 to 10 atom%. The element M ′ in the present invention is one or more elements selected from Si, Ga, Ge, Ru, Sn, Sb, and Pd, forms a solid solution with Fe, and is added by 6 atomic% or less to make it soft. Improve magnetism.

Boron (B) is an essential element of the alloy of the present invention and contributes to amorphous formation. When B exceeds 9 atom%, magnetostriction becomes large under heat treatment conditions with good magnetic properties. Therefore, the preferable range is 0.5 atom% to 9 atom%, more preferably 1 atom% to 9 atom%, and the most preferable range is 2 atom% to 8 atom%. In the present invention, phosphorus (P) and carbon (C) are essential elements, respectively.
Contributes to the expansion of the amorphous formation range. Further, C refines the crystal grains to improve the soft magnetic characteristics. However, when P exceeds 9 atomic%, Fe—P-based crystals are precipitated by heat treatment to inhibit the development of soft magnetism, so the content e of P is more than 2 atomic% and 9 atomic% or less, preferably 2.5 at%. Atomic% to 9 atomic%, and more preferably 3 atomic% to 7 atomic%.

Further, when C exceeds 5 atomic%, Fe—C is likely to be generated by heat treatment and inhibits the expression of soft magnetism. Therefore, the content f of C is 0.1 atomic% to 5 atomic, and preferably. Is 0.5 atom% to 3 atom%, and more preferably 0.5 atom% to 2 atom%. Further, in the alloy of the present invention, the elements M, P and C all have a function of improving the corrosion resistance. In order to obtain such an effect, the preferable range of the total content of these elements is 5.1 atom% <b + e +
f ≦ 34 atomic%, more preferably 10 atomic% <b
+ E + f ≦ 34 atomic%.

Further, in the alloy of the present invention, by adding P and C in combination, the coercive force is reduced and the soft magnetic properties (iron loss and magnetic permeability) are improved. In the composition ratio of P and C (atomic ratio e / f), a preferable range is 1 ≦ e / f ≦
40, preferably 2 <e / f <20, and the most preferred range is 2 ≦ e / f ≦ 7. In the present invention, an alloy containing unavoidable impurities such as N, S, and O to such an extent that the intended characteristics are not deteriorated is also included in the present invention.

In the Fe-based soft magnetic alloy of the present invention, at least 30% or more of the entire structure is composed of fine crystal grains, and the portions other than the fine crystal grains are mainly amorphous and / or the crystalline portions other than the fine crystal grains. Consists of. In the present invention, excellent (soft) magnetic properties are exhibited when the proportion of crystal grains is within the above range.
In the present invention, the proportion of fine crystal grains is substantially 100%.
Shows excellent (soft) magnetic properties. Fe of the present invention
From the viewpoint of magnetic properties, it is particularly preferable that at least 50% or more of the entire structure of the base soft magnetic alloy is composed of fine crystal grains, and most preferably 70% or more is composed of fine crystal grains.

The fine crystal grains contained in the alloy of the present invention mainly have a bcc structure, and it is considered that Fe and Al are mainly contained in M, M ′ and a trace amount of B, P, and C to form a solid solution. To be The fine crystal grains have an average particle size of 1000 angstroms or less, preferably 500 angstroms or less, and more preferably 50 to 300 angstroms. In the present invention, when the average particle size is 1000 angstroms or less, excellent magnetic properties can be obtained.

In the present invention, the proportion of crystal grains in the whole can be experimentally evaluated by an X-ray diffraction method or the like. That is, it can be evaluated from the ratio of the X-ray diffraction intensity of the X-ray diffraction line generated by crystallization and the X-ray diffraction intensity of the halo peculiar to amorphous that decreases with crystallization. Further, in the present invention, the average particle size uses the bcc peak reflection (110) of the X-ray diffraction pattern and the Scherrer's formula (t = 0.
9λ / β cos θ) (Element of X-ray Diffr
action (Second Edition), BD Cullity), 91-
Page 94).

Further, the Fe-based soft magnetic alloy of the present invention has a small magnetostriction and a large magnetic flux density, and preferably has a saturated magnetostriction λs of −.
It is in the range of 5 × 10 ⁻⁶ ≦ λs ≦ + 10 × 10 ⁻⁶ , and the saturation magnetic flux density Bs is preferably 1.2 or more. Such an Fe-based soft magnetic alloy of the present invention is generally a liquid quenching method for forming an amorphous alloy, (for example, a single roll method), a cavitation method, a thin film forming method (for example, a sputtering method, a plating method or a vapor deposition method) or powder. After forming a quenched alloy of the above composition into a ribbon shape, a powder shape, a fiber shape, a fibrous shape or a thin film shape by a body manufacturing method (for example, a mechanical alloying method) or the like, the obtained quenched alloy is formed into a predetermined shape if necessary. After processing into a shape, heat treatment is performed, and at least a part, preferably 30% or more of the entire sample is crystallized. The quenched alloy may be amorphous, or may be an alloy in which amorphous and crystalline are mixed.

Usually, a quenched ribbon is simply prepared by a roll method, and then it is heat treated after being formed into a predetermined shape such as a wound magnetic core. The heat treatment is performed in a vacuum or in an atmosphere of an inert gas such as argon gas or nitrogen gas, a reducing gas such as H ₂ or an oxidizing gas such as air. It is preferably performed in a vacuum or an inert gas atmosphere. Heat treatment temperature is about 2
The temperature is about 00 to 800 ° C, preferably about 300 to 700 ° C, and more preferably about 400 to 700 ° C. The heat treatment time is within 24 hours, preferably 0.5 to 5 hours, more preferably 0.5 to 3 hours. Further, the heat treatment may be performed without a magnetic field or by applying a magnetic field. In the present invention, a soft magnetic alloy excellent in the characteristics of the present invention can be obtained by heat-treating the mixed alloy of amorphous or partially crystalline having the above composition within the above temperature range and the heat treatment time within the above range. .

The alloy of the present invention can be widely used as materials for magnetic heads, high frequency transformers, saturable reactors, choke coils and the like.

[0019]

EXAMPLES The present invention will be further described below with reference to examples. Examples 1 and 2, Comparative Example Using a single roll method, a molten metal containing Fe, Al, Nb, B, P and C was heated to a width of 5 mm in an atmosphere of argon gas at 1 atmospheric pressure.
A thin strip having a thickness of about 20 μm was prepared and used as a sample.
This sample was heat-treated in the presence of nitrogen gas at 600 ° C. for about 1 hour without a magnetic field.

The alloy composition of the obtained Fe-based soft magnetic alloy is shown in Table 1. Further, the saturation magnetic flux density Bs (T), coercive force Hc (mOe), effective magnetic permeability μ at a frequency of 1 KHz and a maximum magnetic field of 5 mOe of the Fe-based soft magnetic alloy obtained in Table 2 were obtained.
(1KHz), frequency 100kHz and maximum magnetic flux density 0.1
The iron loss value Pc (W / Kg) at T and the saturation magnetostriction λs (× 10 ^-6 ) are shown. The elements other than C were determined by ICP analysis, C was converted to carbon dioxide, and the composition was determined by detecting with an infrared detector.

In Examples 1 and 2, α-Fe
The crystallinity of the sample after the heat treatment, which was determined from the diffraction intensity of (110) and the diffraction intensity of the amorphous material, was 80% or more. The average grain size of the crystal grains was 100 Å in the alloy of Example 1 and 120 Å in the alloy of Example 2. As a comparative example, Fe ₇₈ Si
Table 2 also shows the properties of ₉ B ₁₃ (Comparative Example 1, commercial product).

[0022]

[Table 1]

[0023]

[Table 2]

As is clear from Table 2, F of the present embodiment
The e-based soft magnetic alloy showed excellent magnetic properties, and in particular, showed excellent magnetic permeability and low iron loss as compared with conventional magnetic alloys.

[0025]

As is apparent from the above examples, according to the present invention, it is possible to obtain excellent results by adding Al and a specific element to the Fe-B alloy and adding a specific amount of phosphorus and carbon. An Fe-based soft magnetic alloy having soft magnetic properties can be provided.

Claims (9)

[Claims] 1. A general formula (Fe _1-x A _x ) _100-abcdef A
l _a M _b M ′ _c B _d P _e C _f (where A is Co and / or N
i and M are Nb, Mo, W, Ta, Zr, Hf, Ti,
Represents one or more elements selected from V, Cr, Mn, Y and Ce, and M'is Si, Ga, Ge, Ru, S
Represents one or more elements selected from n, Sb, and Pd. x is 0 ≦ x ≦ 0.2, and a, b, c, d,
e and f represent atomic%, and 2 <a ≦ 15 and 3 respectively.
≦ b ≦ 20, 0 ≦ c ≦ 6, 1 ≦ d ≦ 9, 2 <e ≦ 9,
Fe-based soft magnetism, wherein 0.1 ≦ f ≦ 5 is satisfied and the composition ratio e / f (atomic ratio) of P and C is expressed as 1 ≦ e / f ≦ 40). alloy. 2. In the above general formula, b, e and f are b +
The Fe-based soft magnetic alloy according to claim 1, wherein e + f> 10 is satisfied. 3. The F according to claim 1 or 2, wherein at least 30% or more of the structure is composed of fine crystal grains.
e-based soft magnetic alloy. 4. A bc in which the crystal grains are mainly composed of iron.
The Fe-based soft magnetic alloy according to claim 3, which is a c solid solution. 5. The Fe-based soft magnetic alloy according to claim 3, wherein the average grain size of the crystal grains is 1000 angstroms or less. 6. A saturated magnetostriction λs of −5 × 10 ⁻⁶ ≦ λs ≦ + 10.
The Fe-based soft magnetic alloy according to any one of claims 1 to 5, which is in the range of ^{x10 -6} . 7. The Fe-based soft magnetic alloy according to claim 1, having a saturation magnetic flux density Bs of 1.2 T or more. 8. A (Fe _1-x A _x ) _{100 -abcdef} Al _a produced by a liquid quenching method, a thin film production method or a powder production method.
M _b M ′ _c B _d P _e C _f (where A is Co and / or Ni,
M is Nb, Mo, W, Ta, Zr, Hf, Ti, V, C
Represents one or more elements selected from r, Mn, Y and Ce, and M ′ is Si, Ga, Ge, Ru, Sn, S
represents one or more elements selected from b and Pd. x is 0 ≦ x ≦ 0.2, and a, b, c, d, e, f
Represents atomic%, and 2 <a ≦ 15 and 3 ≦ b ≦, respectively.
20, 0 ≦ c ≦ 6, 1 ≦ d ≦ 9, 2 <e ≦ 9, 0.1 ≦
f ≦ 5 is satisfied, and the composition ratio e / f (atomic ratio) of P and C is
A Fe-based soft magnetic alloy obtained by heat-treating a quenched alloy having a composition represented by 1 ≦ e / f ≦ 40). 9. (Fe _1-x A _x ) _100-abcdef Al _a M _b
M ′ _c B _d P _e C _f (wherein A is Co and / or Ni, M is Nb, Mo, W, Ta, Zr, Hf, Ti, V, Cr,
Represents one or more elements selected from Mn, Y and Ce, and M ′ is Si, Ga, Ge, Ru, Sn, Sb,
Represents one or more elements selected from Pd. x
Is 0 ≦ x ≦ 0.2, and a, b, c, d, e, and f are atomic%, and 2 <a ≦ 15, 3 ≦ b ≦ 20,
0 ≦ c ≦ 6, 1 ≦ d ≦ 9, 2 <e ≦ 9, 0.1 ≦ f ≦ 5
And the composition ratio e / f (atomic ratio) of P and C is 1 ≦ e
/ F ≦ 40), a quenching alloy having a composition represented by the formula: liquid quenching method, thin film manufacturing method or powder manufacturing method, and then holding at a heat treatment temperature of 200 ° C. to 800 ° C. for 24 hours or less. A method for producing an Fe-based soft magnetic alloy, comprising: