KR20210135294A - Soft magnetic alloy powder, powdered magnetic core, magnetic parts and electronic devices - Google Patents

Abstract

[Problem] To provide a soft magnetic alloy powder having a low coercive force and capable of obtaining a green magnetic core having a high magnetic permeability.
[Solution] Composition formula (Fe _(1-(α+β)) X1 _α X2 _β ) _{(1-(a+b+c+d+e+f))} M _a B _b P _c Si _d C _e S _f It is a soft magnetic alloy powder consisting of X1 is at least one selected from the group consisting of Co and Ni, and X2 is 1 selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements or more, M is at least one selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V. The content of each component is within a specific range. The amorphization ratio X (%) is 85% or more.

Description

Soft magnetic alloy powder, powdered magnetic core, magnetic parts and electronic devices

The present invention relates to a soft magnetic alloy powder, a powder magnetic core, a magnetic component, and an electronic device.

Patent Document 1 describes a composite magnetic material in which an insulating binder is further mixed with a mixed magnetic powder obtained by mixing an iron-based crystalline alloy magnetic powder and an iron-based amorphous alloy magnetic powder.

Patent Document 2 describes a composite magnetic material in which each particle contained in a mixed magnetic powder obtained by mixing a hard amorphous alloy magnetic powder with an Fe-Ni alloy magnetic powder is coated with a thermosetting resin.

Japanese Patent Laid-Open No. 2004-197218 Japanese Patent Laid-Open No. 2004-363466

An object of the present invention is to provide a soft magnetic alloy powder having a low coercive force and capable of obtaining a compacted magnetic core having a high magnetic permeability.

In order to achieve the above object, the soft magnetic alloy powder of the present invention,

Composition formula (Fe _(1-(α+β)) X1 _α X2 _β ) _{(1-(a+b+c+d+e+f))} M _a B _b P _c Si _d C _e S _f As an alloy powder,

X1 is at least one selected from the group consisting of Co and Ni,

X2 is at least one selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements;

M is at least one selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V,

0≤a≤0.150

0≤b≤0.200

0≤c≤0.200

0≤d≤0.200

0<e≤0.200

0<f≤0.0200

0.100≤a+b+c+d+e≤0.300

0.0001≤e+f≤0.220

α≥0

β≥0

0≤α+β≤0.50

is,

The amorphization ratio X (%) represented by the following formula (1) is 85% or more.

X=100-(Ic/(Ic+Ia))×100 ... (1)

Ic: crystalline scattering integral intensity

Ia: amorphous scattering integral intensity

Since the soft magnetic alloy powder of the present invention has the above characteristics, the coercive force HcJ is sufficiently low. In addition, a powder magnetic core having high magnetic permeability and the like can be obtained by using the soft magnetic alloy powder of the present invention.

In the soft magnetic alloy powder of the present invention, D50 in the particle size distribution on a volume basis may be r, and the average circularity of soft magnetic alloy particles having a particle diameter of r or more and 2r or less may be 0.70 or more.

In the soft magnetic alloy powder of the present invention, D50 in the particle size distribution on a volume basis may be r, and the average circularity of the soft magnetic alloy powder having a particle diameter of r or more and 2r or less may be 0.90 or more.

In the soft magnetic alloy powder of the present invention, the average circularity of the soft magnetic alloy powder having a particle diameter of 25 µm or more and 30 µm or less may be 0.70 or more.

In the soft magnetic alloy powder of the present invention, the average circularity of the soft magnetic alloy powder having a particle diameter of 25 µm or more and 30 µm or less may be 0.90 or more.

In the soft magnetic alloy powder of the present invention, the average circularity of the soft magnetic alloy powder having a particle diameter of 5 µm or more and 10 µm or less may be 0.70 or more.

In the soft magnetic alloy powder of the present invention, the average circularity of the soft magnetic alloy powder having a particle diameter of 5 µm or more and 10 µm or less may be 0.90 or more.

0.0001≤e+f≤0.051 may be sufficient.

0.080<d<0.100 may be sufficient.

0.030<e≤0.050 may be sufficient.

0≤a<0.020 may be sufficient.

The soft magnetic alloy powder of the present invention may contain nanocrystal particles.

The powder magnetic core of the present invention contains the soft magnetic alloy powder described above.

The magnetic component of the present invention includes the soft magnetic alloy powder described above.

The electronic device of the present invention includes the soft magnetic alloy powder described above.

BRIEF DESCRIPTION OF THE DRAWINGS It is an example of the chart obtained by X-ray crystal structure analysis.
Fig. 2 is an example of a pattern obtained by profile fitting the chart of Fig. 1;
3 is a graph showing a particle size distribution.
4 is a graph showing a particle size distribution.
5 is an observation result by Morphology G3.
6A is a schematic diagram of an atomizing apparatus.
Fig. 6B is an enlarged schematic view of the main part of Fig. 6A;

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described.

In order to achieve the above object, the soft magnetic alloy powder according to the present embodiment,

Composition formula (Fe _(1-(α+β)) X1 _α X2 _β ) _{(1-(a+b+c+d+e+f))} M _a B _b P _c Si _d C _e S _f As an alloy powder,

X1 is at least one selected from the group consisting of Co and Ni,

X2 is at least one selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements;

M is at least one selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V,

0≤a≤0.150

0≤b≤0.200

0≤c≤0.200

0≤d≤0.200

0<e≤0.200

0<f≤0.0200

0.100≤a+b+c+d+e≤0.300

0.0001≤e+f≤0.220

α≥0

β≥0

0≤α+β≤0.50

is,

It is characterized in that the amorphization ratio X (%) represented by the following formula (1) is 85% or more.

X=100-(Ic/(Ic+Ia))×100 ... (1)

Ic: crystalline scattering integral intensity

Ia: amorphous scattering integral intensity

Since the soft magnetic alloy powder according to the present embodiment has the above characteristics, the coercive force HcJ is sufficiently low. Moreover, it becomes easy to become a broad particle size distribution. As a result, it is possible to obtain a powder magnetic core or the like having a high magnetic permeability μ using the soft magnetic alloy powder of the present embodiment. In addition, the average circularity of the soft magnetic alloy powder having a particle diameter within a specific range is increased. As a result, a soft magnetic alloy powder having better HcJ can be obtained. Further, a powder magnetic core or the like having a higher magnetic permeability μ can be obtained.

Hereinafter, each component of the soft magnetic alloy powder according to the present embodiment will be described in detail.

M is at least one selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V.

The content (a) of M satisfies 0≤a≤0.150. That is, the soft magnetic alloy powder according to the present embodiment does not need to contain M. From the viewpoint of lowering HcJ, it is preferable to satisfy 0≤a≤0.070. As a increases, the saturation magnetization tends to decrease.

It is more preferable to satisfy 0≤a<0.020. 0≤a≤0.019 may be satisfied. When a is within the above numerical range, the saturation magnetization can be further improved.

The content (b) of B satisfies 0≤b≤0.200. That is, the soft magnetic alloy powder according to the present embodiment does not need to contain B. Moreover, 0.060≤b≤0.200 may be sufficient. When b is too large, the saturation magnetization tends to decrease.

The content (c) of P satisfies 0≤c≤0.200. That is, the soft magnetic alloy powder according to the present embodiment does not need to contain P. Moreover, 0≤c≤0.150 may be sufficient. When c is too large, the saturation magnetization tends to decrease similarly to the case where b is too large.

The Si content (d) satisfies 0≤d≤0.200. That is, the soft magnetic alloy powder according to the present embodiment does not need to contain Si. 0.080<d<0.100 may be sufficient, and 0.085<d<0.095 may be sufficient. When d is too large, the circularity of the soft magnetic alloy powder tends to decrease.

The content (e) of C satisfies 0<e≤0.200. That is, the soft magnetic alloy powder according to the present embodiment necessarily contains C. Moreover, 0.001≤e≤0.150 may be sufficient, and 0.030<e≤0.050 may be sufficient. When the soft magnetic alloy powder according to the present embodiment contains C, HcJ tends to be small. When e is too large, the saturation magnetization tends to decrease similarly to the case where b is too large and when c is too large.

The content (f) of S satisfies 0<f≤0.0200. That is, the soft magnetic alloy powder according to the present embodiment necessarily contains S. Moreover, 0.0001≤f≤0.0200 may be sufficient. When the soft magnetic alloy powder according to the present embodiment contains S, it tends to have a broad particle size distribution, and the magnetic permeability μ of a compact magnetic core produced using the soft magnetic alloy powder tends to increase. However, when the soft magnetic alloy powder according to the present embodiment does not contain C but contains S, HcJ becomes too large. In addition, the magnetic permeability μ of the powder magnetic core and the like also tends to decrease. When f is too large, the soft magnetic alloy powder tends to contain crystals having a crystal grain size of more than 100 nm. And, when the soft magnetic alloy powder contains crystals having a crystal grain size of more than 100 nm, HcJ remarkably increases, and the magnetic permeability μ of a compact magnetic core using the soft magnetic alloy powder tends to decrease.

Further, the soft magnetic alloy powder according to the present embodiment satisfies 0.100≤a+b+c+d+e≤0.300. Moreover, 0.240≤a+b+c+d+e≤0.300 may be sufficient. When a+b+c+d+e exists in said range, various characteristics become easy to improve. When a+b+c+d+e is too small, the soft magnetic alloy powder easily becomes a crystal containing a crystal having a crystal grain size of more than 100 nm. When a+b+c+d+e is too large, the saturation magnetization tends to decrease.

Further, the soft magnetic alloy powder according to the present embodiment satisfies 0.0001≤e+f≤0.220. 0.0001≤e+f≤0.051 may be sufficient. When e+f exists in said range, it becomes easy to improve various characteristics.

From the above, among C and S, when only C is contained and S is not contained, the particle size distribution of the soft magnetic alloy powder becomes sharp. As a result, although the HcJ becomes good, the magnetic permeability μ of the compact magnetic core using the soft magnetic alloy powder does not improve. Among C and S, when only S is contained and C is not contained, HcJ deteriorates, and the effect of improving the magnetic permeability μ of a powder magnetic core using the soft magnetic alloy powder is small. Further, when both C and S are included, but e+f is too large, the soft magnetic alloy powder tends to be a crystal containing crystals having a crystal grain size of more than 100 nm.

Although there is no restriction|limiting in particular about content (1-(a+b+c+d+e+f)) of Fe, 0.699<=1-(a+b+c+d+e+f)<=0.8999 may be sufficient. When 1-(a+b+c+d+e+f) falls within the above range, it becomes difficult for the soft magnetic alloy powder to contain crystals having a crystal grain size of more than 100 nm. Further, the Fe content (1-(a+b+c+d+e+f)) may be 0.740 or more. When 1-(a+b+c+d+e+f) is 0.740 or more, the saturation magnetization tends to become large.

Moreover, in the soft magnetic alloy powder of this embodiment, you may substitute a part of Fe with X1 and/or X2.

X1 is at least one selected from the group consisting of Co and Ni. Regarding the content of X1, α=0 may be sufficient. That is, it is not necessary to contain X1. In addition, the number of atoms of X1 may be 40 at% or less with the total number of atoms in the composition being 100 at%. That is, 0≤α{1-(a+b+c+d+e+f)}≤0.400 may be satisfied.

X2 is at least one selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements. Moreover, from a viewpoint of especially reducing HcJ, 1 or more selected from the group which consists of Al, Zn, Sn, Cu, Cr, and Bi may be sufficient as X2. Regarding the content of X2, β=0 may be sufficient. That is, it is not necessary to contain X2. Moreover, the number of atoms of X2 may be 3.0 at% or less, making the number of atoms of the whole composition 100 at%. That is, 0≤β{1-(a+b+c+d+e+f)}≤0.030 may be satisfied.

The range of the substitution amount for substituting Fe by X1 and/or X2 is not more than half of Fe on an atomic basis. That is, 0≤α+β≤0.50.

In addition, the soft magnetic alloy powder of this embodiment may contain elements other than the above as an unavoidable impurity. For example, you may contain 0.1 weight% or less with respect to 100 weight% of soft magnetic alloy powders.

Moreover, the soft magnetic alloy powder of this embodiment has a structure which consists of amorphous|non-crystalline form. Specifically, the amorphization ratio X represented by the following formula (1) is 85% or more.

X=100-(Ic/(Ic+Ia)×100) … (One)

Ic: crystalline scattering integral intensity

Ia: amorphous scattering integral intensity

The soft magnetic alloy powder with a high amorphization rate X has a small crystal magnetic anisotropy. Accordingly, the magnetic loss of the powder magnetic core using the soft magnetic alloy powder having a high amorphization rate X is small.

The amorphization rate X is the peak of crystallized Fe or compound (Ic: crystalline scattering integrated intensity, Ia: Amorphous scattering integral intensity) is read, the crystallization rate is calculated from the peak intensity, and it is computed by said Formula (1). Hereinafter, the calculation method will be described in more detail.

The soft magnetic alloy powder according to the present embodiment is subjected to X-ray crystal structure analysis by XRD to obtain a chart shown in FIG. 1 . This is profile-fitted using the Lorentz function of the following formula (2), and as shown in FIG. 2 , the crystalline component pattern α _c showing the integrated crystalline scattering intensity, and the amorphous component pattern α _{a indicating the amorphous scattering integrated intensity.} , and a pattern α _c+a that sums them up. From the crystalline scattering integral intensity and amorphous scattering integral intensity of the obtained pattern, the amorphization rate X is calculated|required by said Formula (1). In addition, let the measurement range be the range of the dilution angle 2(theta)=30 degree - 60 degree which can confirm the amorphous-derived halo. In this range, the error between the integral intensity measured by XRD and the integral intensity calculated using the Lorentz function is set to be within 1%.

In addition, the soft magnetic alloy powder of this embodiment may contain the nanocrystal particle as long as the amorphization ratio X (%) is 85 % or more. A nanocrystal particle is a particle|grain containing the nanocrystal whose crystal grain size is 50 nm or less. In addition, whether the soft magnetic alloy powder contains nanocrystal particles can be confirmed by XRD. When the soft magnetic alloy powder contains nanocrystal grains, the HcJ is more likely to be lowered, and the magnetic permeability μ of the powder magnetic core using the soft magnetic alloy powder is likely to increase.

In addition, it is normal that many nanocrystals are contained in a nanocrystal particle. That is, the grain size of the soft magnetic alloy powder and the crystal grain size of the nanocrystals, which will be described later, are different from each other.

Moreover, the soft magnetic alloy powder of this embodiment may be a soft magnetic alloy powder with high sphericity. By having the above composition, it is possible to obtain a soft magnetic alloy powder having a particle shape close to a spherical shape, that is, a soft magnetic alloy powder having a high sphericity.

In general, the higher the amorphization rate X of the soft magnetic alloy powder, the less likely it is that plastic deformation occurs. Therefore, it becomes difficult to increase the filling rate during molding of the powder magnetic core or the like. By making the particle shape of the soft magnetic alloy powder close to a spherical shape, the filling rate of a compact magnetic core using the soft magnetic alloy powder can be increased, and various properties such as the coercive force HcJ and the magnetic permeability μ can be improved.

Moreover, it is preferable that the soft magnetic alloy powder of this embodiment has a high sphericity of a powder with a large particle diameter. Due to the high sphericity of the powder having a large particle size, it becomes possible to further increase the filling factor of the powder magnetic core using the soft magnetic alloy powder, and the magnetic permeability μ is likely to increase.

Hereinafter, the evaluation method of the particle shape and particle diameter (particle size distribution) in the soft magnetic alloy powder of this embodiment is demonstrated.

As described above, the closer the particle shape is to a spherical shape, the better the filling rate of the compact magnetic core using the soft magnetic alloy powder and the like, and various properties such as coercive force can be improved.

In general, the standard of the particle size distribution of the soft magnetic alloy powder includes a volume basis and a number basis. The volume-based particle size distribution is represented by a graph in which the horizontal axis represents the particle diameter and the vertical axis represents the frequency based on the volume. The particle size distribution based on the number is represented by a graph in which the horizontal axis represents the particle diameter and the vertical axis represents the frequency based on the number. When both are overlapped, for example, a graph as shown in FIG. 3 is obtained. The solid line is the particle size distribution based on the volume, and the broken line is the particle size distribution based on the number. D50 of the particle diameter on a volume basis is set to r, and the positions of r and 2r are shown in FIG.

The difference between the particle size distribution based on the volume and the particle size distribution based on the number depends on the difference in the degree to which each particle is reflected in the data. On a volume basis, the degree to which each particle is reflected in the data is proportional to the volume. That is, the degree to which small particles are reflected in the data becomes small. On the other hand, in terms of the number, the degree to which each particle is reflected in the data is equal. That is, the degree to which small particles are reflected in the data increases. Therefore, the difference in said particle size distribution arises.

As described above, the soft magnetic alloy powder of the present embodiment preferably has a high sphericity of the powder having a large particle size. Specifically, the average circularity of particles having a particle diameter of r or more and 2r or less on a number basis may be 0.70 or more, or 0.90 or more. Moreover, the content ratio based on the number of particles having a particle diameter of r or more and 2r or less with respect to the entire soft magnetic alloy powder may be 1% or more and 25% or less. In addition, when only the particle size distribution of the part whose particle diameters are r or more and 2r or less among the particle size distributions on a number basis is extracted, it becomes FIG.

In the soft magnetic alloy powder of the present embodiment, the average circularity of particles having a particle diameter of 25 µm or more and 30 µm or less on a number basis may be 0.70 or more or 0.90 or more. In this case, D50 of the particle diameter on a number basis may be 0.5 micrometer or more and 25 micrometers or less. Moreover, the content ratio based on the number of particle|grains whose particle diameters are 25 micrometers or more and 30 micrometers or less with respect to the whole soft magnetic alloy powder may be 0.1 % or more and 10 % or less.

In the soft magnetic alloy powder of the present embodiment, the average circularity of particles having a particle diameter of 5 μm or more and 10 μm or less on a number basis may be 0.70 or more or 0.90 or more. In this case, D50 of the particle diameter on a number basis may be 0.5 micrometer or more and 5 micrometers or less. Moreover, the content ratio based on the number of particle|grains whose particle diameters are 5 micrometers or more and 10 micrometers or less with respect to the whole soft magnetic alloy powder may be 0.1 % or more and 10 % or less.

In this embodiment, there is no restriction|limiting in particular in the evaluation method of D50(r) of the particle size distribution on a volume basis, and a particle diameter. For example, it can evaluate by the particle size distribution measuring apparatus of the laser diffraction type using Fraunhofer's diffraction theory.

In this embodiment, the particle size distribution on a number basis, etc. are evaluated using Morphology G3 (Malvern Panalytical Co., Ltd.). Morphology G3 is a device that can disperse powder by air, project the shape of individual particles, and evaluate it. The shape of particles having a particle diameter in the range of approximately 0.5 μm to several mm can be evaluated with an optical microscope or a laser microscope. Specifically, as can be seen from the particle shape measurement result 1 shown in FIG. 5 , a large number of particle shapes can be projected and evaluated at once. However, in reality, it is possible to project and evaluate a much larger number of particle shapes at once than those described in the particle shape measurement result 1 shown in FIG. 5 .

Since Morphology G3 can produce and evaluate the projections of a large number of particles at once, it is possible to evaluate the shape of a large number of particles in a short time compared to the evaluation method in the conventional SEM observation or the like. For example, in the examples to be described later, a projection diagram is prepared for 20,000 particles, the particle diameter and circularity of each particle are automatically calculated, and the average circularity of particles having a particle diameter within a specific range is calculated. On the other hand, in the conventional SEM observation, since circularity is calculated for each particle using an SEM image, it is difficult to evaluate the shape of a large number of particles in a short time.

The circularity of the particle is represented by ^{4πS/L 2 ,} with the area in the projection diagram being S and the circumference in the projection diagram being L. The circularity of the circle is 1, and the closer the circularity of the projection of the particle to 1, the higher the circularity of the particle.

In addition, whether the soft magnetic alloy powder of this embodiment has a broad particle size distribution can be evaluated by the magnitude|size of the standard deviation (sigma) of the particle diameter on a number basis.

In addition, when evaluating the various particle size distributions of the soft magnetic alloy powder contained in the powder magnetic core etc., the conventional method by SEM observation can be used. The particle diameter and circularity may be calculated and evaluated from the SEM image for each particle included in an arbitrary cross section, such as a powder magnetic core.

The present inventors discovered that the soft magnetic alloy powder which has a broad particle size distribution can be obtained by controlling the composition of soft magnetic alloy powder. In addition, by controlling the composition of the soft magnetic alloy powder, the HcJ of the entire soft magnetic alloy powder can be controlled.

In addition, the present inventors have found that the HcJ of the entire soft magnetic alloy powder is suitable, and the magnetic permeability µ in a compact magnetic core or the like using the soft magnetic alloy powder having a broad particle size distribution is improved.

In addition, in order to further improve the magnetic permeability μ and withstand voltage characteristics of the HcJ of the whole soft magnetic alloy powder and the powder magnetic core using the soft magnetic alloy powder, it is necessary to control the sphericity of the soft magnetic alloy powder with a large particle diameter. More important than controlling the sphericity of the powder as a whole, the present inventors have found. Specifically, the higher the average circularity of particles having a particle diameter of r or more and 2r or less on a number basis and the average circularity of particles having a particle diameter of 25 μm or more and 30 μm or less on a number basis, the better the magnetic permeability μ and the withstand voltage characteristics tend to be good.

In addition, the sphericity of the whole soft magnetic alloy powder can be changed also by controlling a manufacturing method. However, even if only the manufacturing method is controlled, the soft magnetic alloy powder with a large particle diameter is more difficult to change sphericity than the soft magnetic alloy powder with a small particle diameter. That is, in order to control the sphericity of the soft magnetic alloy powder having a large particle diameter, it was found that it is important to control the composition of the soft magnetic alloy powder and to easily change the particle shape of the soft magnetic powder as a whole by the manufacturing method.

Here, with respect to the volume distribution of the entire soft magnetic alloy powder, a soft magnetic alloy powder having a small particle diameter and a soft magnetic alloy powder having a large particle diameter, which are the same total volume ratio, are considered. When the total volume ratio is equal to each other, the soft magnetic alloy powder having a small particle diameter has a very large number of particles compared to the soft magnetic alloy powder having a large particle diameter. For example, if the total volume ratio is equal to each other, the number of particles in the soft magnetic alloy powder having a particle diameter of 10 μm is about 1/1000 of the number of particles in the soft magnetic alloy powder particles having a particle diameter of 1 μm.

That is, the influence of the sphericity of the soft magnetic alloy powder as a whole on the sphericity of the soft magnetic alloy powder having a large particle diameter and a small number of particles is small. And, regardless of the sphericity of the soft magnetic alloy powder having a large particle diameter, the sphericity of the entire soft magnetic alloy powder may be changed.

Hereinafter, the manufacturing method of the soft magnetic alloy powder of this embodiment is demonstrated.

There is no limitation in particular in the manufacturing method of the soft magnetic alloy powder of this embodiment. For example, the atomization method is mentioned. The type of atomization method is also arbitrary, and a water atomization method, a gas atomization method, etc. are mentioned.

Hereinafter, the manufacturing method of the soft magnetic alloy powder by the water atomization method is described. First, the raw materials are prepared. The raw material to be prepared may be a single substance, such as a metal, or an alloy may be sufficient as it. There is no restriction|limiting in particular also in the form of a raw material. For example, an ingot, a chunk (a lump), or a shot (particle) is mentioned.

Next, the prepared raw materials are weighed and mixed. At this time, it is finally weighed so as to obtain a soft magnetic alloy powder having a target composition. Then, the mixed raw materials are melted and mixed to obtain a molten metal. There is no particular limitation on the mechanism used for melting and mixing. For example, a crucible or the like is used. The temperature of the molten metal may be determined in consideration of the melting point of each metal element, but may be, for example, 1200 to 1600°C.

Then, the soft magnetic alloy powder is produced from the molten metal by the water atomization method. Specifically, the soft magnetic alloy powder can be produced by ejecting the molten metal with a nozzle or the like, making the ejected molten metal collide with a high-pressure water stream to quench it. Further, the composition of the molten metal and the soft magnetic alloy powder is substantially identical.

Here, in order to obtain the target particle diameter of the soft magnetic alloy powder, it is possible to control the particle diameter by controlling the pressure of a high-pressure water flow, the ejection amount of molten metal, etc. Then, a soft magnetic alloy powder having a target particle size distribution is obtained.

The pressure of the high-pressure water flow may be, for example, 50 MPa or more and 100 MPa or less. About the ejection amount of molten metal, 1 kg/min or more and 20 kg/min or less may be sufficient, for example.

Moreover, you may heat-process with respect to the obtained amorphous soft-magnetic alloy powder, and you may make the nanocrystal particle precipitate in the soft-magnetic alloy powder. The conditions of the heat treatment are, for example, 350°C or more and 800°C or less, and are 0.1 minutes or more and 120 minutes or less.

Hereinafter, the manufacturing method of the soft magnetic alloy powder by the gas atomization method is described.

When the present inventors use the atomizing apparatus shown in FIG. 6A and FIG. 6B as an atomizing apparatus, it is easy to produce the soft magnetic alloy powder with a large particle diameter, and it becomes easy to obtain an amorphous soft magnetic metal powder.

As shown to FIG. 6A , the atomizing apparatus 10 has the molten metal supply part 20 and the cooling part 30 arrange|positioned below the metal supply part 20 in the vertical direction. In the drawing, the vertical direction is a direction along the Z axis.

The molten metal supply unit 20 has a heat-resistant container 22 containing the molten metal 21 . In the heat-resistant container 22 , the raw material of each metal element weighed so as to have a composition of the finally obtained soft magnetic alloy powder is melted by the heating coil 24 to form the molten metal 21 . The temperature at the time of dissolution, ie, the temperature of the molten metal 21, may be determined in consideration of the melting point of the raw material of each metal element, but may be, for example, 1200 to 1600°C.

The molten metal 21 is discharged from the discharge port 23 toward the cooling unit 30 as the dripping molten metal 21a. A high-pressure gas is injected from the gas injection nozzle 26 toward the discharged molten metal 21a, the dripping molten metal 21a becomes a large number of volumes, and the cylindrical body 32 follows the flow of the gas. ) is moved toward the inner side of

The gas injected from the gas injection nozzle 26 is preferably an inert gas or a reducing gas. As the inert gas, for example, nitrogen gas, argon gas, helium gas or the like can be used. As a reducing gas, ammonia decomposition gas etc. can be used, for example. However, when the molten metal 21 is a metal that is difficult to oxidize, the gas injected from the gas injection nozzle 26 may be air.

The dripping molten metal 21a transferred toward the inner surface of the cylindrical body 32 collides with the coolant flow 50 formed in an inverted cone shape inside the cylindrical body 32, and is also divided and refined, and is cooled and solidified, It becomes a solid alloy powder. The axis O of the cylindrical body 32 is inclined at a predetermined angle θ1 with respect to the vertical line Z. Although it does not specifically limit as predetermined angle (theta)1, Preferably, it is 0-45 degree|times. With such an angle range, the dripping molten metal 21a from the discharge port 23 is easily discharged toward the cooling liquid flow 50 formed in the inverted cone shape inside the cylinder 32 .

A discharge part 34 is provided below along the axial center O of the cylinder 32 so that the alloy powder contained in the cooling liquid flow 50 can be discharged together with the cooling liquid to the outside. The alloy powder discharged together with the cooling liquid is removed from the cooling liquid in an external storage tank or the like. In addition, although it does not specifically limit as a cooling liquid, Cooling water is used.

In this embodiment, since the dripping molten metal 21a collides with the cooling liquid flow 50 formed in the inverted cone shape, compared with the case where the cooling liquid flow follows the inner surface 33 of the cylindrical body 32, dripping molten metal The flight time of the volume of (21a) is shortened. When the flight time is shortened, the quenching effect is promoted, and the amorphization rate X of the soft magnetic alloy powder obtained is improved. Moreover, the sphericity of the soft magnetic alloy powder with a large particle diameter becomes large easily. Moreover, since the volume of the dripping molten metal 21a is hard to be oxidized when flight time is shortened, refinement|miniaturization of the soft magnetic alloy powder obtained is accelerated|stimulated, and the quality of soft magnetic alloy powder is also improved.

In this embodiment, the cooling liquid in the cooling liquid introduction part (cooling liquid outlet) 36 for introducing the cooling liquid into the inside of the cylindrical body 32 in order to form the cooling liquid flow in an inverted cone shape inside the cylindrical body 32 . control the flow of 6B shows the configuration of the cooling liquid introduction part 36 .

As shown in FIG. 6B, by the frame 38, the outer part (outer space part) 44 located outside the radial direction of the cylindrical body 32, and the inside of the radial direction of the cylindrical body 32. An inner portion (inner space portion) 46 is defined. The outer part 44 and the inner part 46 are a passage part 42 which is partitioned by the partition part 40 and is formed in the upper part of the axial center O direction of the partition part 40. The outer part 44 and the inner part are (46) is in communication, and the cooling liquid can be circulated.

A single or a plurality of nozzles 37 are connected to the outer side portion 44 , and the cooling liquid enters the outer side portion 44 from the nozzles 37 . Further, a cooling liquid discharge unit 52 is formed below the inner side portion 46 in the axial center O direction, and the cooling liquid in the inner side portion 46 is discharged (discharged) into the inside of the cylindrical body 32 from there. .

The outer circumferential surface of the frame body 38 serves as a flow path inner circumferential surface 38b for guiding the flow of the cooling liquid in the inner side portion 46 , and the lower end 38a of the frame body 38 has an inner circumferential flow path inner circumferential surface of the frame body 38 ( Continuing from 38b), an outward convex portion 38a1 protruding outward in the radial direction is formed. Accordingly, the ring-shaped gap between the tip of the outer convex portion 38a1 and the inner surface 33 of the cylindrical body 32 becomes the cooling liquid discharge portion 52 . A flow path deflecting surface 62 is formed on the flow path side upper surface of the outward convex portion 38a1.

As shown in FIG. 6B , the radial width D1 of the coolant discharge portion 52 is narrower than the radial width D2 of the main portion of the inner portion 46 by the outward convex portion 38a1. . Since D1 is narrower than D2, the cooling liquid that descends below the shaft center O along the flow path inner circumferential surface 38b inside the inner side portion 46 flows along the flow path deflecting surface 62 of the frame body 38 next. It collides with the inner surface 33 of the cylinder 32 and reflects. As a result, as shown in FIG. 6A , the cooling liquid is discharged from the cooling liquid discharge unit 52 into the inside of the cylinder 32 in an inverted cone shape to form the cooling liquid flow 50 . Further, when D1 = D2, the cooling liquid discharged from the cooling liquid discharge unit 52 forms a cooling liquid flow along the inner surface 33 of the cylinder 32 .

D1/D2 is preferably 2/3 or less, more preferably 1/2 or less, and most preferably 1/10 or more.

In addition, the cooling liquid flow 50 flowing out from the cooling liquid discharge unit 52 is an inverted cone flow that proceeds straight from the cooling liquid discharge unit 52 toward the axis O, but may be a spirally inverted cone flow.

In addition, the ejection amount gas injection pressure of the molten metal, the pressure in the cylinder 32, the cooling liquid discharge pressure, D1/D2, etc. may be appropriately set according to the target particle diameter of the soft magnetic alloy powder. The ejection amount of the molten metal may be, for example, 1 kg/min or more and 20 kg/min or less. The gas injection pressure may be, for example, 0.5 MPa or more and 19 MPa or less. The pressure in the cylinder 32 may be 0.5 MPa or more and 19 MPa or less, for example. The cooling liquid discharge pressure may be, for example, 0.5 MPa or more and 19 MPa or less.

The smaller the amount of molten metal ejected, the smaller the particle diameter tends to be, and the amorphous soft magnetic alloy powder tends to be easily produced.

As the gas injection pressure, the internal pressure of the cylinder 32, and the cooling liquid discharge pressure are higher, the particle diameter tends to decrease and the circularity of the particles tends to decrease.

Moreover, about a particle diameter, particle size adjustment is possible by sieve classification, airflow classification, etc., for example. Hereinafter, the method of performing particle size adjustment by sieve classification is demonstrated.

In the sieve classification, for example, the particle size can be adjusted by changing the powder addition amount per one time, the classification time and/or the mesh size. Then, a soft magnetic alloy powder having a desired particle size is obtained by appropriately controlling the powder addition amount per one time, the classification time and/or the mesh size.

As the amount of powder added per one time increases, the average circularity of the particles tends to decrease. As the classification time is shorter, the average circularity of the particles tends to decrease. The larger the mesh size, the easier it is to decrease the average circularity of the particles.

As another method of adjusting the particle size, there is a method of changing the number of times the powder is passed through the mesh. Even if the mesh size is the same, it is possible to extract more irregular particles by increasing the number of times the powder is passed through the mesh. It is also possible to improve the average circularity of the powder by extracting more irregular particles.

You may adjust a particle size by mix|blending several types of soft magnetic alloy powder.

The use of the soft magnetic alloy powder according to the present embodiment is not particularly limited. For example, a powder magnetic core is mentioned. When the soft magnetic alloy powder according to the present embodiment is used, a suitable magnetic permeability μ can be easily obtained even if the pressure at the time of producing the powder magnetic core is relatively low. This is because, because the particle size distribution is broadened, the obtained powder magnetic core can be easily densified even when the pressure at the time of manufacturing the powder magnetic core is relatively low. Specifically, the pressure at the time of manufacturing the powder magnetic core can be, for example, 98 MPa or more and 1500 MPa or less.

Further, the powder magnetic core according to the present embodiment can be suitably used as a powder magnetic core for an inductor, particularly for a power inductor. Moreover, it can be used suitably also for the inductor which integrally molded the powder magnetic core and the coil part.

Moreover, it can be suitably used also for the magnetic component using soft magnetic alloy powder, for example, a thin film inductor, and a magnetic head. In addition, the powdered magnetic core and magnetic component using the soft magnetic alloy powder can be suitably used for electronic devices.

[Example]

Hereinafter, the present invention will be specifically described based on Examples.

(Experimental Example 1)

Ingots of various materials were prepared and weighed so that a master alloy having the composition shown in Table 1 shown below was obtained. And it accommodated in the crucible arrange|positioned in the water atomizing apparatus. Next, using a work coil installed outside the crucible in an inert atmosphere, the crucible was heated to 1500° C. by high-frequency induction, and the ingot in the crucible was melted and mixed to obtain a molten metal (molten metal).

Then, from a nozzle installed in the crucible, the molten metal in the crucible was ejected, and at the same time, the ejected molten metal was collided with a high-pressure water stream of 100 MPa to be quenched, thereby producing soft magnetic alloy powders of Examples and Comparative Examples shown in Table 1. In addition, it was confirmed by ICP analysis that the composition of the master alloy and the composition of the soft magnetic alloy powder were substantially identical.

Each of the obtained soft magnetic alloy powders was sieved. The conditions of sieve classification were 0.5 kg of addition amount per one time, and classification time was 1 minute. In addition, the mesh size was set to 38 micrometers.

It was confirmed whether each of the obtained soft magnetic alloy powders consisted of amorphous or crystalline form. The amorphization rate X of each thin strip was measured using XRD, and when X was 85% or more, it was said to be amorphous. If X is less than 85%, it is said to be crystallized. A result is shown in Table 1.

HcJ and Bs were measured for each obtained soft magnetic alloy powder. HcJ was measured using an Hc meter. A result is shown in Table 1. In Experimental Example 1, HcJ made 2.4Oe or less favorable, and made 1.0Oe or less more favorable. Bs made 0.70T or more favorable, and made 1.40T or more more favorable.

The shape of the powder particles in each of the obtained soft magnetic alloy powders was evaluated. Specifically, D50(r) on a volume basis, D50 on a number basis, σ on a number basis, and average circularity at particle diameters r or more and 2r or less on a number basis were evaluated. A result is shown in Table 1.

In Experimental Example 1, D50(r) on a volume basis was 10 to 11 µm, and D50 on a number basis was 4 to 5 µm.

D50(r) on a volume basis was measured using a laser diffraction particle size distribution analyzer (HELOS & RODOS, Sympatec).

D50 and sigma on a number basis were measured by observing the shapes of 20,000 powder particles at a magnification of 10 times using Morphology G3 (Malvern Panalytical). Specifically, the soft magnetic alloy powder for a volume of 3 cc was dispersed at an air pressure of 1 to 3 bar, and a projected image by a laser microscope was photographed. Rather than the particle diameter of each powder particle, D50 and (sigma) on a number basis were computed. In addition, the particle diameter of each powder particle was made into the round equivalent diameter.

In Experimental example 1, the case where sigma was 2.5 micrometers or more was made favorable.

The average circularity at the particle diameter r or more and 2r or less on a number basis was calculated by measuring and averaging the circularity of the powder particles each having a particle diameter of r or more and 2r or less among 20,000 powder particles.

Next, a toroidal core was produced from each soft magnetic alloy powder. Specifically, each soft magnetic alloy powder is mixed so that the amount of phenol resin used as an insulating binder becomes 3% by mass of the total, and a general planetary mixer is used as a stirrer to obtain a coarse powder of about 500 μm. assembled Next, the obtained granulated powder was shape|molded by the surface pressure of 4 ton/cm<^2> (392 MPa), and the toroidal-shaped molded object with an outer diameter of 13 mmφ, an inner diameter of 8 mmφ, and a height of 6 mm was produced. The obtained molded object was hardened at 150 degreeC, and the toroidal core was produced.

Then, the UEW wire was wound around the toroidal core, and μ (permeability) was measured at 100 kHz using a 4284A PRECISION LCR METER (Hewlett-Packard). In Experimental Example 1, the case where µ was 25 or more was considered favorable.

[Table 1]

In Table 1, in all the Examples and Comparative Examples, the average circularity in the particle diameter r or more and 2r or less on the basis of the number was 0.70 or more.

In Table 1, the soft magnetic alloy powder of Sample No. 1, which is a comparative example not containing C and S, had a high HcJ and a low σ. And μ of the toroidal core was also low.

The soft magnetic alloy powder of Sample Nos. 5 to 7, which is a composition in which only S was added to the soft magnetic alloy powder of Sample No. 1, compared with the soft magnetic alloy powder of Sample No. 1, the HcJ was further increased by the addition of S. And, similarly to Sample No. 1, μ of the toroidal core was also low.

The soft magnetic alloy powders of Sample Nos. 2 to 4, which have a composition in which only C was added to the soft magnetic alloy powder of Sample No. 1, compared with the soft magnetic alloy powder of Sample No. 1, HcJ decreased, but σ also decreased. And compared with Sample No. 1, µ of the toroidal core also decreased.

The soft magnetic alloy powders of Examples of Sample Nos. 8 to 12, which are compositions in which S was added within a specific range to the soft magnetic alloy powder of Sample No. 2, had good HcJ and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good. In Sample No. 13, which had an excessively large content (f) of S, the soft magnetic alloy powder contained crystals having a crystal grain size of 100 nm or more, and the amorphization ratio X was less than 85%. And Hcj increased remarkably. In addition, μ of the toroidal core was also low.

Sample Nos. 14 to 17 are soft magnetic alloy powders of Comparative Examples in which P content (c) and C content (e) are changed without containing M, Si and S. Sample Nos. 14-17 had a low σ and a low μ of the toroidal core. Moreover, in Sample No. 17 with a large content of C, HcJ also rose.

Sample Nos. 18 to 21 were soft magnetic alloy powders of Examples having a composition in which the S content (f) was changed from 0 to 0.0010 with respect to Sample Nos. 14 to 17, and had good HcJ and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Sample Nos. 22 to 24 are soft magnetic alloy powders of Comparative Examples having compositions in which the B content (b), the Si content (d), and the C content (e) are changed without containing M, P and S. Sample Nos. 22-24 had a low σ and a low μ of the toroidal core.

Sample Nos. 25 to 27 were soft magnetic alloy powders of Examples having a composition in which the S content (f) was changed from 0 to 0.0010 with respect to Sample Nos. 22 to 24, and had good HcJ and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Each Example of Sample Nos. 25-27 had a small Bs compared with each Example of Sample Nos. 8-12 and 18-21. This is because the Fe content is small.

Sample Nos. 28 to 30 and 28a to 28d are soft magnetic alloy powders of Examples containing Nb as M differently from the above Examples. HcJ and σ were good as in the Example not including M. Moreover, Bs of the Example which satisfies 0≤a<0.020 was favorable compared with Bs of the Example which satisfies a≥0.020. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

In addition, for each Example of Experimental Example 1, the average circularity in the particle diameter of 25 μm or more and 30 μm or less on a number basis, and the average circularity in the particle diameter of 5 μm or more and 10 μm or less on a number basis were calculated in the same way. As a result, in all Examples, the average circularity at particle diameters of 25 μm or more and 30 μm or less on a number basis was 0.70 or more, and the average circularity at particle diameters 5 μm or more and 10 μm or less on a number basis was 0.90 or more.

(Experimental Example 2)

In Experimental example 2, it carried out similarly to Experimental example 1 except the point which changed the atomization method from the water atomization method to the gas atomization method, and the conditions of sieve classification. The atomizing apparatus shown to FIG. 6A and FIG. 6B was used.

Ingots of various materials were prepared and weighed so that a master alloy having a composition shown in Table 2 shown below was obtained.

Next, the master alloy was accommodated in the heat-resistant container 22 arranged in the atomizing device 10 . Then, after making the inside of the cylinder 32 into a vacuum, using the heating coil 24 provided outside the heat resistant container 22, the heat resistant container 22 is heated by high frequency induction, and the heat resistant container 22 The raw metal in the mixture was melted and mixed to obtain a molten metal (molten metal) at 1500°C.

By injecting the obtained molten metal into the cylinder 32 of the cooling part 30 at 1500 degreeC, and injecting argon gas with the injection gas pressure of 7 MPa, it was set as many volumes. The volume collided with the inverted cone-shaped cooling water flow formed by the cooling water supplied at a pump pressure (coolant discharge pressure) of 10 MPa to become a fine powder, which was then recovered. In addition, the pressure in the cylinder 32 was made into 0.5 MPa.

Moreover, in the atomizing apparatus 10 shown in FIG. 6, the inner diameter of the inner surface of the cylinder 32 was 300 mm, D1/D2 was 1/2, and angle (theta)1 was 20 degrees.

Each of the obtained soft magnetic alloy powders was sieved. The conditions of sieve classification were made into 0.05 kg of addition amount per one time, and classification time 5 minutes. In addition, the mesh size was made into 63 micrometers of eyes.

In Experimental Example 2, unlike Experimental Example 1, D50(r) on a volume basis was 22 to 27 µm, and D50 on a number basis was 8 to 9 µm. Moreover, in Experimental Example 2, the average circularity in the particle diameter r or more and 2r or less on a number basis in all the Examples and Comparative Examples became 0.90 or more. Moreover, in Experimental example 2, sigma made 7.0 micrometers or more favorable. Moreover, the magnetic permeability micro of a toroidal core made 33 or more favorable. A result is shown in Table 2.

[Table 2]

In Table 2, in all the Examples and Comparative Examples, the average circularity in the particle diameter r or more and 2r or less on the basis of the number was 0.90 or more.

In Table 2, the soft magnetic alloy powder of Sample No. 31, which is a comparative example not containing C and S, had a high HcJ and a low σ. And μ of the toroidal core was also low.

The soft magnetic alloy powder of Sample Nos. 35 to 37, which is a composition in which only S was added to the soft magnetic alloy powder of Sample No. 31, compared with the soft magnetic alloy powder of Sample No. 31, the HcJ was further increased by the addition of S. And similarly to Sample No. 31, μ of the toroidal core was also low.

The soft magnetic alloy powders of Sample Nos. 32 to 34, which have a composition in which only C was added to the soft magnetic alloy powder of Sample No. 31, compared with the soft magnetic alloy powder of Sample No. 31, HcJ decreased but σ also decreased. And compared with Sample No. 31, µ of the toroidal core also decreased.

The soft magnetic alloy powders of Examples of Sample Nos. 38 to 42, which are compositions in which S was added within a specific range to the soft magnetic alloy powder of Sample No. 32, had good HcJ and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good. Moreover, in Sample No. 43, which had too much S content (f), the soft magnetic alloy powder consisted of crystals having a crystal grain size of 100 nm or more, and Hcj increased remarkably. In addition, μ of the toroidal core was also low.

Sample Nos. 44 to 47 are soft magnetic alloy powders of Comparative Examples in which P content (c) and C content (e) are changed without containing M, Si, and S. Sample Nos. 44-47 had a low σ and a low μ of the toroidal core. Moreover, HcJ also rose in Sample No. 47 with a large content of C.

Sample Nos. 48 to 51 were soft magnetic alloy powders of Examples having a composition in which the S content (f) was changed from 0 to 0.0010 with respect to Sample Nos. 44 to 47, and had good HcJ and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Sample Nos. 52 to 54 are soft magnetic alloy powders of Comparative Examples having compositions in which the B content (b), the Si content (d), and the C content (e) are changed without containing M, P and S. Sample Nos. 52-54 had a low σ and a low μ of the toroidal core.

Sample Nos. 55 to 57 were soft magnetic alloy powders of Examples having a composition in which the S content (f) was changed from 0 to 0.0010 with respect to Sample Nos. 52 to 54, and had good HcJ and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Each Example of Sample Nos. 55-57 had a small Bs compared with Examples of Sample Nos. 38-42 and 48-51. This is because the Fe content is small.

Sample Nos. 58 to 60 and 58a to 58d are soft magnetic alloy powders of Examples containing Nb as M differently from the above Examples. HcJ and σ were good as in the Example not including M. Moreover, Bs of the Example which satisfies 0≤a<0.020 was favorable compared with Bs of the Example which satisfies a≥0.020. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Sample Nos. 60a and 60b are soft magnetic alloy powders of Examples in which the Fe content has a composition higher than that of Sample Nos. 31 to 60. Even when the Fe content was increased, HcJ and σ were favorable. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

In addition, various soft magnetic alloy powders of Sample Nos. 61 to 70 were produced under the same conditions as Sample No. 58, except that the type of M was changed. In addition, various soft magnetic alloy powders of Sample Nos. 61b to 70b were produced under the same conditions as Sample No. 58b except that the type of M was changed. A result is shown in Table 3.

[Table 3]

In Table 3, Sample Nos. 61 to 70, in which the type of M was changed, gave good test results to the same degree as Sample No. 58. Moreover, sample Nos. 61b-70b became favorable test results to the same degree as sample No. 58b.

(Experimental Example 3)

In Experimental Example 3, soft magnetic alloy powder of Sample No. 71 satisfying a=0.000, b=0.120, c=0.090, d=0.030, e=0.010, f=0.0010, and α=β=0 was produced. Moreover, sample numbers 72-125 in which the kind and content of X1 and/or X2 were changed suitably from sample number 71 were implemented. The conditions for producing the soft magnetic alloy powder in Experimental Example 3 were the same as in Experimental Example 2 except for the composition of the soft magnetic alloy powder. A result is shown in Table 4.

[Table 4]

In Table 4, the soft magnetic alloy powders of Sample Nos. 71 to 125 having compositions within the scope of the present invention had suitable HcJ, Bs, and σ. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

(Experimental Example 4)

In Experimental Example 4, Sample Nos. 126 to 128 under the same conditions as in Experimental Example 3, except that the average circularity based on the number of soft magnetic alloy powders was changed by changing the amount of powder added per one time in sieving with respect to Sample No. 71. of soft magnetic alloy powder was produced. A result is shown in Table 5. In addition, in Table 5, the specific numerical value of the average circularity in the particle diameter of 25 micrometers or more and 30 micrometers or less on a number basis is also shown.

In addition, in Experimental Example 4, the withstand voltage characteristics were measured together with the magnetic permeability of the toroidal core. In the measurement of the withstand voltage characteristic, first, an In-Ga electrode was formed on the back surface perpendicular to the thickness direction of the toroidal core. Next, a voltage was applied using a source meter, and the voltage when a current of 1 mA passed was measured. Then, the withstand voltage characteristic was measured by dividing the voltage by the thickness of the toroidal core.

[Table 5]

In Table 5, the soft magnetic alloy powders of Sample Nos. 126 to 128, in which the average circularity of the soft magnetic alloy powders were changed, had HcJ and σ suitable for the same as those of Sample No. 71. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Moreover, there was a tendency that the withstand voltage characteristics of the toroidal core tend to be more favorable as the average circularity in r or more and 2r or less and the average circularity in 25 µm or more and 30 µm or less were higher.

(Experimental Example 5)

In Experimental Example 5, with respect to Sample No. 8, Sample Nos. 130- 136 soft magnetic alloy powder was produced. Further, in the same manner as in Experimental Example 4, the magnetic permeability and withstand voltage characteristics of the toroidal core using the soft magnetic alloy powder of each sample were measured. A result is shown in Table 6. In addition, Table 6 also shows the specific numerical values of the average circularity in the particle diameters of 25 micrometers or more and 30 micrometers or less on a number basis, and the average circularity in the particle diameters 5 micrometers or more and 10 micrometers or less on a number basis.

[Table 6]

In Table 6, the soft magnetic alloy powders of Sample Nos. 8 and 130 to 136, in which the average circularity of the soft magnetic alloy powder was changed, had suitable HcJ and σ as in each Example of Experimental Example 1. In addition, μ of the toroidal core using the soft magnetic alloy powder was also good.

Moreover, there was a tendency that the withstand voltage characteristics of the toroidal core tend to be more favorable as the average circularity in r or more and 2r or less and the average circularity in 25 µm or more and 30 µm or less were higher.

(Experimental Example 6)

In Experimental Example 6, the injection gas pressure of gas atomization was changed in the range of 2 MPa or more and 15 MPa or less, and 6 types of samples A-F from which a particle size and a shape differ from each other were created. Sample Nos. 71, 137, and 138 were produced by blending Samples A to F. For Samples 137 and 138, the average circularity at particle diameters r or more and 2r or less on a number basis and average circularity at particle diameters 25 μm or more and 30 μm or less on a number basis were close to Sample 71, and included in the soft magnetic alloy powder It is a sample in which the average circularity of all particles is changed. Table 7B shows the injection gas pressure of Samples A to F, D50 on a number basis, and the average circularity of all particles. In addition, the compounding ratio (mass ratio) of Samples A to F is shown in Table 7C. In addition, Sample C is the same as Sample No. 71, and manufacturing conditions other than the injection gas pressure of the gas atomization of Samples A-F are the same as that of Sample No. 71. Then, the magnetic permeability and withstand voltage characteristics of the toroidal core using the soft magnetic alloy powder of each sample were measured. The results are shown in Table 7A.

[Table 7A]

[Table 7B]

[Table 7C]

In Table 7A, even if the average circularity of all particles changes, the composition, the average circularity at particle diameters r or more and 2r or less based on the number, and the average circularity at the particle diameters 25 μm or more and 30 μm or less based on the number are the same as before the change When a very high value was shown, it could be confirmed that the same good result as before the change was obtained.

(Experimental Example 7)

In Experimental Example 7, soft magnetic alloy powders of Sample Nos. 139, 139a, 140, and 140a were produced under the same conditions except that the P content (c) and the Si content (d) were appropriately changed from Sample No. 71. A result is shown in Table 8.

[Table 8]

In Table 8, sample numbers 71, 139a, and 140a satisfying 0.080 < d < 0.100, compared with sample numbers 139 and 140 that do not satisfy 0.080 < d < 0.100, decreased HcJ, resulting in good HcJ. became

(Experimental Example 8)

In Experimental Example 8, soft magnetic alloy powders of Sample Nos. 141a and 141 to 143 were produced under the same conditions except that the B content (b) and C content (c) were appropriately changed from Sample No. 71. A result is shown in Table 9.

[Table 9]

In Table 9, sample numbers 71, 141a, 141, and 142 satisfying 0.0001≤e+f≤0.051 have a larger σ compared to sample number 143 that does not satisfy 0.0001≤e+f≤0.051, and The permeability μ also increased.

In Table 9, sample Nos. 141a and 142 satisfying 0.030<e≤0.050, compared with Sample Nos. 71, 141, and 143 which do not satisfy 0.030<e≤0.050, the magnetic permeability μ of the toroidal core was increased.

(Experimental Example 9)

In Experimental Example 9, the soft magnetic alloy powder of Sample No. 59 was subjected to heat treatment to prepare a soft magnetic alloy powder of Sample No. 142 in which nanocrystals were deposited in the soft magnetic alloy. Heat treatment conditions were made into 60 minutes at 520 degreeC. In addition, in the soft magnetic alloy powder of Sample No. 151, nanocrystal particles having a crystal grain size of 30 nm or less and a crystal structure of bcc were precipitated, and the amorphization ratio X (%) of the soft magnetic alloy powder of Sample No. 151 was 85 % or more was confirmed by XRD. A result is shown in Table 10.

[Table 10]

In Table 10, in Sample No. 151, in which nanocrystal grains were precipitated by heat treatment, HcJ decreased and the magnetic permeability μ of the toroidal core increased, compared to Sample No. 59 before heat treatment.

1 Particle shape measurement result
10 atomizing device
20 Molten metal supply
21 Molten Metal
21a dripping molten metal
30 cooling
36 coolant inlet
38a1 Outward convex portion
50 coolant flow

Claims (15)

Composition formula (Fe _(1-(α+β)) X1 _α X2 _β ) _{(1-(a+b+c+d+e+f))} M _a B _b P _c Si _d C _e S _f As an alloy powder,
X1 is at least one selected from the group consisting of Co and Ni,
X2 is at least one selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements;
M is at least one selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V,
0≤a≤0.150
0≤b≤0.200
0≤c≤0.200
0≤d≤0.200
0<e≤0.200
0<f≤0.0200
0.100≤a+b+c+d+e≤0.300
0.0001≤e+f≤0.220
α≥0
β≥0
0≤α+β≤0.50
is,
The soft magnetic alloy powder whose amorphization rate X (%) represented by following formula (1) is 85 % or more.
X=100-(Ic/(Ic+Ia))×100 ... (1)
Ic: crystalline scattering integral intensity
Ia: amorphous scattering integral intensity The method according to claim 1,
A soft magnetic alloy powder, wherein D50 in the particle size distribution on a volume basis is r, and the average circularity of the soft magnetic alloy particles having a particle diameter of r or more and 2r or less is 0.70 or more. The method according to claim 1,
A soft magnetic alloy powder, wherein D50 in the particle size distribution on a volume basis is r, and the average circularity of the soft magnetic alloy powder having a particle diameter of r or more and 2r or less is 0.90 or more. The method according to claim 1,
The soft magnetic alloy powder, wherein the average circularity of the soft magnetic alloy powder having a particle diameter of 25 µm or more and 30 µm or less is 0.70 or more. The method according to claim 1,
The soft magnetic alloy powder, wherein the average circularity of the soft magnetic alloy powder having a particle diameter of 25 μm or more and 30 μm or less is 0.90 or more. The method according to claim 1,
The soft magnetic alloy powder, wherein the average circularity of the soft magnetic alloy powder having a particle diameter of 5 μm or more and 10 μm or less is 0.70 or more. The method according to claim 1,
The soft magnetic alloy powder, wherein the average circularity of the soft magnetic alloy powder having a particle diameter of 5 μm or more and 10 μm or less is 0.90 or more. 8. The method according to any one of claims 1 to 7,
Soft magnetic alloy powder, wherein 0.0001≤e+f≤0.051. 9. The method according to any one of claims 1 to 8,
0.080<d<0.100, soft magnetic alloy powder. 10. The method according to any one of claims 1 to 9,
0.030<e≤0.050, soft magnetic alloy powder. 11. The method according to any one of claims 1 to 10,
0≤a<0.020, soft magnetic alloy powder. 12. The method according to any one of claims 1 to 11,
The soft magnetic alloy powder contains nanocrystal particles, soft magnetic alloy powder. A powder magnetic core comprising the soft magnetic alloy powder according to any one of claims 1 to 12. A magnetic component comprising the soft magnetic alloy powder according to any one of claims 1 to 12. An electronic device comprising the soft magnetic alloy powder according to any one of claims 1 to 12.

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