JPS62167840A - Magnetic material and its manufacture - Google Patents

Abstract

PURPOSE:To obtain magnetic material having extremely low iron loss and permanent magnetic permeability in high frequency range, by prescribing a specified compsn. composed of Co as main component, Fe and Ni, etc., as auxiliary components and Si, B in Co amorphous alloy. CONSTITUTION:Magnetic material is indicated by a compsn. formula, further in amorphous state in >=80% thereof, and has magnetic characteristic of permanent permeability. Here, M is one kind or more among Ni, Mn, Cr, Mo, W, V, Nb, Ta, Ru, Ti, Zr, and relations of 0<=x<=0.2, 0<=a<=20, 0<=b<=20, 0<=c<=20, 5<=b+c<=30 are satisfied in atomic ratio. Amorphous alloy having the compsn. is annealed while being applied with magnetic field in direction orthogonal to that of excitation during the usage to provide magnetic characteristic of permanent permeability thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic material that is made of an amorphous alloy containing Co as a main component and has extremely low core loss in a high frequency range, and a method for manufacturing the same.

[Conventional technology]

In general, amorphous alloys have excellent soft magnetic properties and low magnetic loss, and because they have high electrical resistance and thin plate thickness, they have the advantage of low loss due to eddy current and extremely low iron loss. If such an amorphous alloy is manufactured as is, the strain introduced when it is rapidly cooled causes domain wall pinning and magnetic anisotropy, and as a result, good magnetic properties cannot be obtained, so it is usually annealed. The soft magnetic properties have been completely improved. In the thin ribbon, uniaxial anisotropy exists in the longitudinal direction, and mere annealing as described above results in a magnetic domain structure with domain walls extending 180° in the longitudinal direction. When VC is excited in the longitudinal direction, it exhibits excellent magnetic properties such as small coercive force and high magnetic permeability in direct current, but when excited in a high frequency range, eddy current loss increases and does not necessarily exhibit good properties.

In order to improve these properties, we applied heat treatment in an oblique magnetic field and scratched the surface of the ribbon.

Attempts have been made to subdivide magnetic domains and reduce iron loss by means such as precipitation of fine crystal grains. For example, JP-A-57
-202709 has B-H characteristics with a low squareness ratio in direct current by annealing an Fe-based amorphous alloy at a temperature below the Curie point while applying a magnetic field in a direction substantially perpendicular to the excitation direction. It has been proposed to obtain magnetic materials, and also JJppl.

Phys, , Mol, 54, Nll 1,
1983, p. 6554, it is reported that transition metals are added to reduce magnetostriction and subdivide magnetic domains, thereby reducing iron loss.

The industrial demand for lower iron loss is increasing, and switching power supplies, for example, are becoming smaller and lighter, more efficient, and more reliable.

Development is progressing with the aim of lowering costs, and one promising solution is attempting to raise the switching frequency even higher. There is a need for magnetic materials that can withstand use in Trance.

In general, the higher the saturation magnetic flux density of the magnetic material used for the coil, the greater the amplitude of the magnetic flux density, which is advantageous, but on the other hand, iron loss increases in the high frequency range of tens of KHz or more Its use is restricted due to the heat it generates. Therefore, reducing iron loss is the most important point. On the other hand, for transformers and coils of the type that are used with superimposed direct current, magnetic materials with constant magnetic permeability, high saturation magnetic flux density, and low residual magnetization are advantageous. Conventionally, constant magnetic permeability has been obtained by creating an air gap in magnetic materials, and efforts are being made to develop magnetic materials that themselves have constant magnetic permeability.

[Problem that the invention seeks to solve]

As mentioned above, Co-based amorphous alloys can be selected to have a composition with zero magnetostriction, have low coercive force, have lower magnetic loss than Fe-based amorphous alloys, and are theoretically more effective than metal loss in the high frequency range. Can be made smaller. However, on the other hand, Co
Heat treatment methods for amorphous alloys have not been sufficiently studied. This is due to the common sense that a high saturated L8 flux density is required for the core material, and the Co-based amorphous alloy, which has a lower saturated m-density than the Fe-based amorphous alloy, takes advantage of its high magnetic permeability. The reality is that it is limited to only one use. In addition, as mentioned above, in order to cope with the increasing switching frequency of switching power supplies, it is technically more important to reduce iron loss than to determine the saturation magnetic flux density. The development of magnetic materials with low core loss through improvement is industrially important, and the development of magnetic materials with low core loss and constant magnetic permeability is also expected.

An object of the present invention is to provide a magnetic material with extremely low core loss in a high frequency range and a method for manufacturing the same. Furthermore, as a result of numerous test and research studies, it has been found that magnetic materials with constant magnetic permeability have small hysteresis loss and can reduce iron loss, so we will also provide magnetic materials with constant magnetic permeability and a method for manufacturing the same. It is something.

[Flat membrane to solve problems]

The present invention was made to solve such problems, that is, the composition formula (col-X Fex) toO-a
−b−c Represented by MaSibBc, M is Ni, Mn,
Cr, Mo, W, V, Nb.

Any one of Ta, Ru, Ti, Zr 1〒■ or 2) ff1 or more, atomic ratio O≦x≦0.2,
O≦a≦20≦a≦20゜O≦c≦20, 5≦b+c
A magnetic material is a material that satisfies the relationship of ≦30 and in which 80 or more parts thereof are in an amorphous state, and is characterized by having a magnetic property of constant magnetic permeability. Furthermore, the present invention provides magnetic properties of constant magnetic permeability by applying a magnetic field in a direction substantially perpendicular to the direction of magnetization during use at a temperature below one Curie point when annealing the Co-based amorphous alloy. This is an attempt to create a magnetic material tS with reduced iron loss in the high frequency range.

In the magnetic material of the present invention, the main component is Co, Fe is an additive element mainly to reduce magnetostriction to zero, and M is a secondary component, which has the effect of reducing magnetostriction and raising the crystallization temperature. This is to reduce iron loss in the high frequency range by changing the magnetic domain structure. 3i and B are metalloid elements essential for amorphization, and if b~c is less than 5 at% or exceeds 30 at%, amorphization becomes extremely difficult. When both Si and Bt are contained, it is easier to make the material amorphous than when they are used alone, and stable production is possible. Practically speaking, it is more preferable for each of Si and B to be 20 at % or less. If a large amount of Fe is contained, the saturation magnetic flux density will increase, but the magnetostriction will be greatly reduced, which is disadvantageous in reducing iron loss, so it is necessary to limit X to 0.2 or less. If the amount of the secondary component added is excessive, the deviation from the zero magnetostriction composition will increase, and the magnetic properties will deteriorate, such as the saturation magnetic flux density being too low, so a is limited to 20 at % or less.

When the above-mentioned OCO-based amorphous alloy of the present invention is annealed at a temperature below one Curie point while applying a magnetic field in a direction substantially perpendicular to the excitation direction during use, the coercive force is small and the residual magnetization is substantially zero. A material is obtained. Also, d-1 of the material to be annealed (where W is the mass of the material to be annealed (rl,
d is density [(r/ffd), t is length in the direction of magnetic field application -)
The strength of the magnetic field applied during annealing is changed according to the value, and if the value is appropriate, a magnetic material with constant magnetic permeability and direct current magnetic properties can be obtained. This material maintains a constant magnetic permeability characteristic even in a high frequency range of several tens of KH2 or more, and has a characteristic that the core loss is significantly smaller than that of conventional materials.

Co-based amorphous alloys are generally manufactured by a molten metal quenching method and provided as long thin ribbons, so it is practical to set the excitation direction in the longitudinal direction of the ribbon and the direction of the magnetic field during annealing to be in the width direction of the ribbon. It is.

Here, the magnetic field applied during annealing and the (−
Let me briefly explain the relationship with g).

Generally, when a ferromagnetic material with a finite size is placed in a magnetic field and magnetized, magnetic poles are generated at both ends due to the magnetization, and a magnetic field in the opposite direction to the magnetic field applied from the outside, called a demagnetizing field, is generated. . This demagnetizing field cancels out the externally applied magnetic field, and the strength of the magnetic field (effective magnetic field) that is hostage applied to the material becomes smaller than the external field. Perpendicular to the direction of magnetic field application 7j of the material to be annealed: The larger the cross-sectional area (d), the larger the magnetic poles generated on both end surfaces of the material.
It is thought that the demagnetizing field becomes stronger. Like the above invention,
When attempting to obtain desired properties by changing the magnetic properties of a material by annealing it in a magnetic field, the strength of the effective tapping of the externally applied magnetic field is important, and the strength of the material to be annealed is important. It is considered that the effective magnetic field necessary to obtain predetermined magnetic properties can only be obtained by changing the strength of the external magnetic field during annealing according to (1) - t.

[For production]

In the present invention, by setting the material composition to one that satisfies the composition according to the above formula, it has been possible to provide an appropriate material that can meet the various demands mentioned above.

[Embodiments of the invention]

Example, 1 (COo, 94 F'e0.06)755i15 B
FIG. 1 shows the DC magnetic properties of a magnetic material obtained by annealing an amorphous alloy ribbon having a composition of IO and manufactured by a single roll method while applying a magnetic field in the width direction of the ribbon. The above thin strip was wound in a troigle shape, with an inner diameter of 14.7 m and an outer diameter of 15.9 r.
An XIR wound core was used and annealed for 10 minutes at a temperature of 310° C. below the Curie point while applying a magnetic field of 0.9 KOe.

The DC magnetic characteristics were measured by fully winding the excitation coil and detection coil on the annealed wound core. The excitation direction is the circumferential direction of the wound core, which corresponds to the longitudinal direction of the ribbon and is at an angle with the width direction.

The DC magnetic properties exhibit constant magnetic permeability, low coercive force, and essentially zero residual magnetization.

Next, Figure 2 shows the AC B-H of the same material at 50 KHz.
Although this is a curve diagram, the magnetic properties in the high frequency range also show constant magnetic permeability. Here, FIGS. 6 and 7 are comparative diagrams showing the magnetic properties of conventional products, and show the magnetic properties of a material having the same composition as in Example 1 and heat treated at the same temperature in a rotating magnetic field. The DC B-H curve diagram in Fig. 6 shows high magnetic permeability and low coercive force, and has a high squareness ratio, but in the high frequency range, as shown in Fig. 7, the coercive force becomes large, and the hysteresis loss is lower than that of the above embodiment. Larger than magnetic materials. FIG. 3 shows a comparison of iron loss in the high frequency range between the example magnetic material and the conventional material.

The figure shows that the magnetic material of the present invention has significantly reduced iron loss compared to conventional non-noso-malloy, ferrite, and amorphous alloy (Allied Co., Ltd. 2605-83) that undergoes conventional heat treatment. is clear.

Example, 2 (COo, 04 Feo, o6) 71 MnLaWLa
A toroidal core was prepared by winding an amorphous alloy ribbon (density d = 8.16 (Jlc)) with a width of IC 1 m having a composition of Si7B15, and the iron loss and DC magnetic properties were annealed in a magnetic field. Figure 4 shows the dependence of the strength of the applied magnetic field during annealing.The core used for the measurement had a mass of 3.31, and the magnetic field was applied in the width direction of the ribbon.

The case marked with 0 in Fig. 4 is a case where the applied magnetic field is too weak compared to the cross-sectional area, and it remains transparent even when the squareness ratio is low as shown in Fig. 4(a) and the 7'CB-H curve diagram. There is no magnetic flux, and there is little reduction in iron loss. If the applied magnetic field indicated by the Δ mark in Figure 4 is too strong, the permeability becomes constant as shown in the B-H curve diagram shown in Figure 4 (c), but the iron loss is the optimum value shown by the mouth mark in Figure 4. It is slightly larger than that for magnetic field strength. and B in Figure 4(c)
As shown in the −H curve diagram, the BIO (magnetic flux density at 100e) decreases, resulting in practically disadvantageous properties for applications where the operating magnetic flux density of the core is increased.

Example 3 Amorphous 1-alloy thin strips in each electrode plate having the same composition as in Example 2 above were prepared, and this was wound to produce wound cores having various scorches and shapes. did. This iron core is heat-treated while applying a magnetic field in the width direction of the ribbon. When f ), t is the width of the ribbon -), the strength of the applied magnetic field, and the DC magnetic properties after heat treatment are shown in FIG.

In the same figure, the mouth is close to constant magnetic permeability but not perfect, ○ is constant magnetic permeability, Δ is constant magnetic permeability but 13to has decreased, × is constant magnetic permeability. Indicate the cases that did not occur. From FIG. 5, it is clear that the optimum magnetic field strength is the ratio d- to -W- of the material to be treated, and its optimum range is 4.3 (
-3M-)-1,5≦H≦4.3(-!-)+2.3(
However, H is always greater than zero at the strength of the applied magnetic field (KOe) when annealing d-1d- is dull.

As mentioned above, this invention was made for the purpose of reducing iron loss in a high frequency range and providing a magnetic material with constant magnetic permeability. The use is not limited to.

Further, although the embodiments have mainly been described with respect to wound cores, the present invention is not limited to wound iron cores, and the shape of the magnetic material may be a thin ribbon, a secondary magnetic core made by laminating thin ribbons, or other shapes. Good too.

〔Effect of the invention〕

As described above, according to the present invention, a Co-based amorphous alloy is annealed while applying a magnetic field in a direction substantially perpendicular to the excitation direction, and the strength of the magnetic field is adjusted according to the above-mentioned processing of the material to be heat treated. By appropriately selecting a magnetic material, it is possible to obtain a magnetic material with constant magnetic permeability characteristics both in direct current and in the high frequency range, and by using this material, it is possible to obtain a core with extremely low core loss in the high frequency range. The effect of its use is very strong.

[Brief explanation of drawings]

FIG. 1 shows the magnetic characteristics of an embodiment of the present invention.
4 curve diagram, Figure 2 is the crossflow B-H curve diagram of the same example, and Figure 3 is
The figure is an iron loss-magnetic flux density diagram showing a comparison of the iron loss between -SIt and the example of this invention and the secondary magnetic material, and Fig. 4 is the iron loss and iM flow magnetic characteristics of another example of this invention. Figure 5W is a diagram showing the dependence of the applied magnetic field during annealing, and Figure 6 is a diagram showing the influence of n of the material to be annealed and the magnetic field applied during annealing on the magnetic properties. DC B-H curve diagram showing magnetic properties of crystalline alloy,
FIG. 7 is an AC B-H curve diagram of the same material as FIG. 6.

Claims (6)

[Claims] (1) Composition formula (Co_1_-_xFe_x)_1_0_
0_-_a_-_b_-_cM_aSi_bB_c, M is Ni, Mn, Cr, Mo, W, V, Nb, T
Any one or more of a, Ru, Ti, and Zr, and the atomic ratio is 0≦x≦0.2, 0≦a≦20, 0≦b≦
20. A magnetic material that satisfies the following relationships: 0≦c≦20, 5≦b+c≦30, and that 80% or more of the material is in an amorphous state, and has a magnetic property of constant magnetic permeability. (2) Composition formula (Co_1_-_xFe_x)_1_0_
0_-_a_-_b_-_cM_aSi_bB_c, M is Ni, Mn, Cr, Mo, W, V, Nb, T
a, Ru, Ti, and Zr) 0≦x≦0.2, 0≦a≦20, 0≦b≦ in atomic ratio
20, satisfies the relationships 0≦c≦20, 5≦b+c≦30,
Magnetism, characterized in that a material of which 80% or more is in an amorphous state is annealed while applying a magnetic field in a direction substantially perpendicular to the excitation direction during use, and is made to have magnetic properties of constant magnetic permeability. Method of manufacturing the material. (3) The method for manufacturing a magnetic material according to claim 2, wherein the excitation direction is the longitudinal direction of the ribbon, and the direction of the applied magnetic field during annealing is the width direction of the ribbon. (4) Adjust the strength of the magnetic field applied during annealing to the W of the material to be annealed.
/(d・l) (where W is the mass of the material to be annealed (
Magnetism according to claim 2 or 3, wherein g) and d are density (g/cm^3), and l is increased in proportion to the length (cm) in the direction of magnetic field application. Method of manufacturing the material. (5) Magnetic field strength during annealing is 4.3 (W/(d・l))
-1.5≦H≦4.3(W/(d・l))+2.3 (where H is the strength of the magnetic field (KOe) and H>0). A method for producing a magnetic material according to claim 4. (6) A method for producing a magnetic material according to any one of claims 2 to 5, wherein the material to be annealed is a wound core made of a thin ribbon wound.