JP6845205B2 - Soft magnetic alloy strips and magnetic parts - Google Patents

Description

The present invention relates to soft magnetic alloy strips and magnetic components.

In recent years, low power consumption and high efficiency have been required in electronic, information, communication equipment and the like. Furthermore, the above demands are becoming stronger toward a low-carbon society. Therefore, power supply circuits for electronic, information, and communication equipment are also required to reduce energy loss and improve power supply efficiency.

It is known that a soft magnetic alloy strip is used as a material for manufacturing a core of a magnetic element used in a power supply circuit. In this case, in addition to the soft magnetic properties of the soft magnetic alloy strip itself, the space factor of the core after the core is made using the soft magnetic alloy strip, that is, the proportion of the conductor in the cross section of the core is also high. Is required.

Patent Document 1 describes a Fe—B—Si based Fe-based amorphous alloy strip. By controlling the surface roughness of the Fe-B-Si-based Fe-based amorphous alloy strip, the saturation magnetic flux density of the strip itself is improved, and the space factor of the core after the core is manufactured is also high. can do.

International Publication No. 2018/062037

An object of the present invention is to provide a soft magnetic alloy strip having a high saturation magnetic flux density and a low coercive force, and capable of providing a core having a high space factor and a high saturation magnetic flux density.

In order to achieve the above object, the soft magnetic alloy strip of the present invention can be used.
Composition formula (Fe _{(1- (α + β))} X1 _α X2 _β ) _{(1- (a + b + c + d + e + f))} M _a B _b P _c S _d C _{e S f} A soft magnetic alloy strip having a main component.
X1 is one or more selected from the group consisting of Co and Ni,
X2 is one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements.
M is one or more selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V.
0 ≤ a ≤ 0.140
0.020 ≤ b ≤ 0.200
0 ≦ c ≦ 0.150
0 ≦ d ≦ 0.090
0 ≦ e ≦ 0.030
0 ≦ f ≦ 0.030
α ≧ 0
β ≧ 0
0 ≤ α + β ≤ 0.50
And
At least one of a, c and d is greater than 0,
The soft magnetic alloy strip has a structure composed of Fe-based nanocrystals.
The soft magnetic alloy strip has a peeling surface and a free surface perpendicular to the thickness direction.
The soft magnetic alloy strip has an edge portion and a central portion along the width direction, and has an edge portion and a central portion.
When measuring the arithmetic mean roughness along the width direction on the peeled surface, the average value of the arithmetic mean roughness in the central portion is defined as Ra _c , and the average value of the arithmetic mean roughness in the edge portion is defined as Ra _e .
0.85 ≤ Ra _e / Ra _c ≤ 1.25
Meet.

The soft magnetic alloy strip of the present invention has a high saturation magnetic flux density and a low coercive force by having the above composition, a structure composed of Fe-based nanocrystals, and the above average roughness, and is occupied. It is a soft magnetic alloy strip that can provide a core with a high rate and a high saturation magnetic flux density.

In the soft magnetic alloy strip of the present invention, the average particle size of the Fe-based nanocrystals may be 5 to 30 nm.

The soft magnetic alloy strip of the present invention may have 0.73 ≦ 1- (a + b + c + d + e + f) ≦ 0.91.

The soft magnetic alloy strip of the present invention may be 0 ≦ α {1- (a + b + c + d + e + f)} ≦ 0.40.

The soft magnetic alloy strip of the present invention may have α = 0.

The soft magnetic alloy strip of the present invention may be 0 ≦ β {1- (a + b + c + d + e + f)} ≦ 0.030.

The soft magnetic alloy strip of the present invention may have β = 0.

The soft magnetic alloy strip of the present invention may have α = β = 0.

The soft magnetic alloy ribbon of the present invention, Ra _c may be not more than 0.50 .mu.m.

The soft magnetic alloy strip of the present invention may have an average maximum height roughness of 4.3 μm or less when the maximum height roughness is measured along the casting direction on the free surface.

The magnetic component of the present invention comprises the above-mentioned soft magnetic alloy strip.

FIG. 1 is a schematic view of the single roll method. FIG. 2 is a schematic view of the single roll method. FIG. 3 is a schematic view showing the positions of the edge portion and the central portion. FIG. 4 is an example of a chart obtained by X-ray crystal structure analysis. FIG. 5 is an example of a pattern obtained by profile fitting the chart of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Dimensions of soft magnetic alloy thin band)
The size of the soft magnetic alloy strip of the present embodiment is arbitrary. For example, the soft magnetic alloy strip 24 having the shape shown in FIG. 3 has a thickness (length in the z-axis direction) of 15 to 30 μm and a width (length in the y-axis direction) of 100 to 1000 mm. May be good.

When the thickness of the soft magnetic alloy strip 24 is 15 μm or more, it becomes easy to sufficiently maintain the mechanical strength and workability. Further, it becomes easy to reduce the surface undulation (waviness), and it becomes easy to sufficiently increase the space factor of the core. When the thickness is 30 μm or less, it becomes easy to prevent embrittlement during casting. Further, coarse crystals are less likely to be formed on the soft magnetic alloy strip 24 before the heat treatment. The space factor of the core is the ratio of conductors in the cross section of the core.

When the width of the soft magnetic alloy thin band 24 is 100 mm or more, the saturation magnetic flux density can be easily improved. This is because the influence of the edge portion 41, which tends to reduce the saturation magnetic flux density, is reduced. Further, when the width is 1000 mm or less, the saturation magnetic flux density can be easily improved. This is because it is easy to make the cooling rate uniform over the entire thin band during casting, which will be described later.

Further, as shown in FIG. 3, the soft magnetic alloy strip 24 of the present embodiment has an edge portion 41 and a central portion 43 along the width direction (y-axis direction).

The edge portion 41 of the soft magnetic alloy thin band 24 is a region up to 20 mm from the edge of the soft magnetic alloy thin band 24 toward the center (the portion where the distances from both edges are equal) along the y-axis direction, that is, one of them. Refers to a region where the distance from the edge is 0 to 20 mm.

The central portion 43 of the soft magnetic alloy thin band 24 is 3L / 8 from one edge of the soft magnetic alloy thin band 24 toward the other edge along the y-axis direction, where L is the width of the soft magnetic alloy thin band 24. It refers to a region of ~ 5L / 8, i.e. a region where the distances from both edges are both 3L / 8-5L / 8.

(Composition of soft magnetic alloy strip)
The soft magnetic alloy ribbon 24 of this embodiment, the composition formula _{(Fe (1- (α + β} )) X1 α X2 β) (1- (a + b + c + d + e + f)) The main consisting of _{M a B b P c Si d} C e S f Has ingredients and
X1 is one or more selected from the group consisting of Co and Ni,
X2 is one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements.
M is one or more selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V.
0 ≤ a ≤ 0.140
0.020 ≤ b ≤ 0.200
0 ≦ c ≦ 0.150
0 ≦ d ≦ 0.090
0 ≦ e ≦ 0.030
0 ≦ f ≦ 0.030
α ≧ 0
β ≧ 0
0 ≤ α + β ≤ 0.50
And
At least one or more of a, c and d is larger than 0 and has a structure composed of Fe-based nanocrystals.

When the soft magnetic alloy strip having the above composition is heat-treated, Fe-based nanocrystals are likely to be precipitated in the soft magnetic alloy strip 24. In other words, the soft magnetic alloy strip having the above composition can be easily used as a starting material for the soft magnetic alloy strip 24 in which Fe-based nanocrystals are precipitated.

The soft magnetic alloy strip having the above composition before heat treatment may have a structure consisting only of amorphous material, or may have a nanoheterostructure in which initial microcrystals are present in amorphous material. .. The initial microcrystals may have an average particle size of 0.3 to 10 nm. In the present embodiment, when the amorphization rate described later is 85% or more, it is assumed that it has a structure consisting of only amorphous or has a nanoheterostructure.

Here, the Fe-based nanocrystal is a crystal having a particle size on the nano-order and a Fe crystal structure of bcc (body-centered cubic lattice structure). In this embodiment, it is preferable to precipitate Fe-based nanocrystals having an average particle size of 5 to 30 nm. The soft magnetic alloy strip 24 on which such Fe-based nanocrystals are precipitated tends to have a high saturation magnetic flux density and a low coercive force. In the present embodiment, when the structure contains Fe-based nanocrystals, the amorphization rate described later is less than 85%.

Hereinafter, a method for confirming whether the soft magnetic alloy strip has a structure composed of an amorphous phase (a structure composed only of an amorphous phase or a nanoheterostructure) or a structure composed of a crystalline phase will be described. In the present embodiment, the soft magnetic alloy strip having an amorphization rate X of 85% or more represented by the following formula (1) has a structure composed of an amorphous phase, and the amorphization rate X is 85%. It is assumed that the soft magnetic alloy strip having less than or less than has a structure composed of a crystalline phase.
X = 100- (Ic / (Ic + Ia) x 100) ... (1)
Ic: Crystalline scattering integral strength Ia: Amorphous scattering integral strength

The amorphization rate X is determined by X-ray crystallographic analysis of the soft magnetic alloy strip by XRD to identify the phase, and the peak of the crystallized Fe or compound (Ic: crystalline scattering integrated intensity, Ia: Amorphous scattering integrated intensity) is read, the crystallinity is calculated from the peak intensity, and calculated by the above formula (1). Hereinafter, the calculation method will be described in more detail.

An X-ray crystal structure analysis is performed on the soft magnetic alloy strip according to the present embodiment by XRD to obtain a chart as shown in FIG. This is profile-fitted using the Lorentz function of the following equation (2), and the crystal component pattern α _c showing the crystalline scattering integral intensity and the amorphous component showing the amorphous scattering integral intensity as shown in FIG. 5 are performed. A pattern α _a and a combined pattern α _{c + a} are obtained. From the crystalline scattering integrated intensity and the amorphous scattering integrated intensity of the obtained pattern, the amorphization rate X is obtained by the above formula (1). The measurement range is a diffraction angle of 2θ = 30 ° to 60 ° at which an amorphous-derived halo can be confirmed. Within this range, the error between the integrated intensity actually measured by XRD and the integrated intensity calculated by using the Lorentz function was set to be within 1%.

Hereinafter, each component of the soft magnetic alloy strip 24 according to the present embodiment will be described in detail.

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

The content (a) of M satisfies 0 ≦ a ≦ 0.140. That is, it does not have to contain M. The content (a) of M preferably satisfies 0.020 ≦ a ≦ 0.120, more preferably 0.040 ≦ a ≦ 0.100, and more preferably 0.060 ≦ a ≦ 0.080. Is particularly preferred. When a is large, the saturation magnetic flux density tends to decrease.

Further, the smaller a is, the larger the surface roughness of the soft magnetic alloy thin band 24, which will be described later, tends to be. Further, when a is too large, the surface roughness ratio described later tends to be small.

The content (b) of B satisfies 0.020 ≦ b ≦ 0.200. Further, 0.025 ≦ b ≦ 0.200 may be set, 0.060 ≦ b ≦ 0.150 is preferable, and 0.080 ≦ b ≦ 0.120 is more preferable. When b is small, a crystal phase composed of crystals having a particle size of more than 30 nm is likely to be formed in the soft magnetic alloy strip before heat treatment, and when a crystal phase is formed, Fe-based nanocrystals may be precipitated by heat treatment. Can not. Then, the coercive force tends to increase. When b is large, the saturation magnetic flux density tends to decrease.

Further, the smaller b is, the larger the surface roughness of the soft magnetic alloy thin band 24, which will be described later, tends to be. Further, if b is too large or too small, the surface roughness ratio described later tends to be small.

The content (c) of P satisfies 0 ≦ c ≦ 0.150. That is, it does not have to contain P. Further, 0.030 ≦ c ≦ 0.100 is preferable, and 0.030 ≦ c ≦ 0.050 is more preferable. When c is large, the saturation magnetic flux density tends to decrease.

Further, the smaller c is, the larger the surface roughness of the soft magnetic alloy thin band 24, which will be described later, tends to be. Further, when c is too large, the surface roughness ratio described later tends to be small.

The Si content (d) satisfies 0 ≦ d ≦ 0.090. That is, it does not have to contain Si. Further, it is preferable that 0 ≦ d ≦ 0.020. By containing Si, it becomes easy to reduce the coercive force. When d is large, the coercive force tends to increase on the contrary.

Further, the larger d is, the smaller the surface roughness of the soft magnetic alloy thin band 24, which will be described later, tends to be.

The content (e) of C satisfies 0 ≦ e ≦ 0.030. That is, C does not have to be contained. Further, it is preferable that 0.001 ≦ e ≦ 0.010. By containing C, the coercive force can be easily lowered. When e is large, a crystal phase composed of crystals having a particle size of more than 30 nm is likely to be formed in the soft magnetic alloy strip before the heat treatment, and when a crystal phase is formed, Fe-based nanocrystals may be precipitated by the heat treatment. Can not. Then, the coercive force tends to increase.

The S content (f) satisfies 0 ≦ f ≦ 0.030. That is, S does not have to be contained. By containing S, it becomes easy to reduce the surface roughness described later. When f is large, a crystal phase composed of crystals having a particle size of more than 30 nm is likely to be formed in the soft magnetic alloy strip before heat treatment, and when a crystal phase is formed, Fe-based nanocrystals may be precipitated by heat treatment. Can not. Then, the coercive force tends to increase.

Further, in the soft magnetic alloy strip of the present embodiment, at least one or more of a, c, and d is greater than 0. That is, it contains at least one or more of M, P, and Si. When at least one or more of a, c, and d is greater than 0, it means that at least one or more of a, c, and d is 0.001 or more. Further, at least one or more of a and c may be larger than 0. That is, at least one or more of M and P may be contained. Further, considering that the coercive force is significantly reduced, a is preferably larger than 0.

The Fe content (1- (a + b + c + d + e + f)) is not particularly limited, but may be 0.73 ≦ (1- (a + b + c + d + e + f)) ≦ 0.95, or 0.73 ≦ (1- (a + b + c + d + e + f)). )) ≤ 0.91. By setting (1- (a + b + c + d + e + f)) within the above range, it becomes more difficult for a crystal phase composed of crystals having a particle size of more than 30 nm to occur during the production of the soft magnetic alloy strip.

Further, in the soft magnetic alloy strip of the present embodiment, a part of Fe may be replaced with X1 and / or X2.

X1 is one or more selected from the group consisting of Co and Ni. The content of X1 may be α = 0. That is, X1 does not have to be contained. Further, the number of atoms of X1 is preferably 40 at% or less, assuming that the number of atoms in the entire composition is 100 at%. That is, it is preferable to satisfy 0 ≦ α {1- (a + b + c + d + e + f)} ≦ 0.40.

X2 is one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements. Regarding the content of X2, β = 0 may be used. That is, X2 does not have to be contained. Further, the number of atoms of X2 is preferably 3.0 at% or less, assuming that the number of atoms in the entire composition is 100 at%. That is, it is preferable to satisfy 0 ≦ β {1- (a + b + c + d + e + f)} ≦ 0.030.

The range of the substitution amount for substituting Fe with X1 and / or X2 is set to half or less of Fe on the basis of the number of atoms. That is, 0 ≦ α + β ≦ 0.50. When α + β> 0.50, it becomes difficult to obtain the soft magnetic alloy of the second embodiment by heat treatment.

The soft magnetic alloy strip of the present embodiment may contain elements other than the above as unavoidable impurities. For example, 0.1% by weight or less may be contained with respect to 100% by weight of the soft magnetic alloy strip.

(Surface morphology of soft magnetic alloy strip)
Generally, when the soft magnetic alloy strip 24 is manufactured by a method using a roll 23 such as the single roll method shown in FIGS. 1 and 2, the surface form of the soft magnetic alloy strip 24 is a peeling surface 24a (roll 23). The surface in contact with the surface of the roll 23) and the free surface 24b (the surface not in contact with the surface of the roll 23) are different. The peeling surface 24a and the free surface 24b are surfaces perpendicular to the thickness direction, and the peeling surface 24a and the free surface 24b can be visually distinguished from each other.

(Peeled surface of soft magnetic alloy thin band)
In the soft magnetic alloy strip 24 according to the present embodiment, when the arithmetic average roughness Ra is measured along the width direction (y-axis direction) on the peeled surface 24a, the average value of Ra in the central portion 43 is Ra _c . The average value of Ra in the edge portion 41 is set to Ra _e , and 0.85 ≦ Ra _e / Ra _c ≦ 1.25 is satisfied. Hereinafter, Ra _e / Ra _c may be simply referred to as a surface roughness ratio.

The soft magnetic alloy strip 24 having the above composition, having a structure composed of Fe-based nanocrystals, and having a surface roughness ratio within the above range has a low coercive force and a high saturation magnetic flux density. It becomes a thin band 24. That is, the soft magnetic alloy strip 24 having excellent soft magnetic characteristics is obtained.

When the surface roughness ratio is out of the above range, the residual stress of the soft magnetic alloy strip 24 tends to increase. In addition, the residual stress restricts the rotation of the magnetic moment, and the saturation magnetic flux density tends to decrease. On the other hand, if the surface roughness ratio is too large, the space factor tends to decrease when the core is produced by laminating the soft magnetic alloy strips 24. Then, the saturation magnetic flux density of the core tends to decrease.

Further, the soft magnetic alloy ribbon 24 according to the present embodiment may also be Ra _c is 0.50μm or less is preferably less 0.41 .mu.m. By ra _c is less than or equal to 0.50 .mu.m, it tends to reduce residual stress of the soft magnetic alloy ribbon 24. Further, when the core is produced by laminating the soft magnetic alloy thin strips 24, the space factor can be easily improved. Incidentally, if not the lower limit of the Ra _c is present, when the Ra _c is to produce a soft magnetic alloy ribbon 24 is less than 0.1μm by a single roll method to be described later, the roll is excessively polished is there. Therefore, Ra _c may also be 0.1μm or more from the viewpoint of production stability of the soft magnetic alloy ribbon 24.

The method for measuring the surface roughness of the soft magnetic alloy strip 24 according to the present embodiment may be a contact type or a non-contact type. The method for measuring the surface roughness conforms to JIS-B0601. Specifically, the measurement length is 4.0 mm, the cutoff wavelength is 0.8 mm, and the cutoff type is 2RC (phase uncompensated).

For Ra _e , three measurement points of the arithmetic average roughness Ra are set at the edge portion 41, and the measured arithmetic average roughness is averaged and calculated. The measurement direction is the width direction (y-axis direction). This is because the arithmetic mean roughness in the width direction represents the degree of adhesion of the paddle at the initial stage of thin band formation, and strongly affects the thin band formation.

For ra _c, it sets three places the measurement point of the arithmetic average roughness at the center portion 43, is calculated by averaging the arithmetic mean roughness measured. The measurement direction is the width direction (y-axis direction). This is because the arithmetic mean roughness in the width direction represents the degree of adhesion of the paddle at the initial stage of thin band formation, and strongly affects the thin band formation.

(Free surface of soft magnetic alloy thin band)
The surface roughness of the soft magnetic alloy strip 24 according to the present embodiment on the free surface 24b is arbitrary. However, when the maximum height roughness Rz is measured along the x-axis direction (casting direction), it is preferable that the Rz _c is 4.3 μm or less, where the average value of the Rz in the central portion 43 is Rz _c. By reducing Rz _c , it becomes easier to further improve the saturation magnetic flux density of the soft magnetic alloy thin band 24. Incidentally, if not the lower limit of Rz _c is present, when the Rz _c attempts to produce a soft magnetic alloy ribbon 24 is less than 0.1μm by a single roll method to be described later, the roll is excessively polished is there. From the viewpoint of manufacturing stability of the soft magnetic alloy strip 24, Rz _c may be 0.1 μm or more.

For Rz _c , three measurement points of the maximum height roughness Rz are set in the central portion 43, and the measured maximum height roughness is averaged and calculated. The measurement direction is the casting direction (x-axis direction). This is because when the soft magnetic alloy strip 24 is manufactured by a method using a roll 23 such as the single roll method shown in FIGS. 1 and 2, grooves are periodically formed on the free surface 24b in the casting direction. Is.

(Manufacturing method of soft magnetic alloy thin band)
Hereinafter, a method for producing the soft magnetic alloy strip of the present embodiment will be described.

The method for producing the soft magnetic alloy strip of the present embodiment is arbitrary. For example, there is a method of manufacturing a soft magnetic alloy strip by a single roll method. Moreover, the thin band may be a continuous thin band.

In the single roll method, first, the pure metal of each metal element contained in the finally obtained soft magnetic alloy strip is prepared, and weighed so as to have the same composition as the finally obtained soft magnetic alloy strip. Then, the pure metal of each metal element is melted and mixed to prepare a mother alloy. The method for melting the pure metal is arbitrary, but for example, there is a method in which the pure metal is evacuated in a chamber and then melted by high-frequency heating. The mother alloy and the finally obtained soft magnetic alloy strip have the same composition.

Next, the produced mother alloy is heated and melted to obtain a molten metal (molten metal). The temperature of the molten metal is not particularly limited, but can be, for example, 1200 to 1500 ° C.

FIG. 1 shows a schematic view of an apparatus used in the single roll method according to the present embodiment. In the single roll method according to the present embodiment, the thin band 24 is manufactured in the rotation direction of the roll 23 by injecting and supplying the molten metal 22 from the nozzle 21 to the roll 23 rotating in the direction of the arrow inside the chamber 25. Will be done. In this embodiment, the material of the roll 23 is arbitrary. For example, a roll made of Cu is used.

On the other hand, FIG. 2 shows a schematic diagram of an apparatus used in a commonly used single roll method. Inside the chamber 25, the thin band 24 is manufactured in the direction of rotation of the roll 23 by injecting and supplying the molten metal 22 from the nozzle 21 to the roll 23 rotating in the direction of the arrow.

In the present embodiment, the temperature of the roll 23 is set to 50 to 90 ° C., which is higher than the conventional one, and the differential pressure (injection pressure) between the chamber and the injection nozzle is set to 20 to 80 kPa, so that the surface roughness ratio is in a predetermined range. It becomes easy to be inside. The injection pressure is preferably 30 to 80 kPa.

If the temperature of the roll 23 is too low, the surface roughness becomes large due to the influence of water molecules adsorbed on the surface of the roll 23, and the surface roughness ratio becomes small. The surface roughness ratio is small because the influence of water molecules is greater in the central portion 43 than in the edge portion 41. If the temperature of the roll 23 is too high, it becomes difficult to form the thin band 24. Further, even if the thin band 24 can be formed, the surface roughness becomes large.

If the injection pressure is too small, it becomes difficult to form the thin band 24. Further, even if the thin band 24 can be formed, the surface roughness becomes large and the surface roughness ratio becomes small. If the injection pressure is too high, the edge portion 41 of the thin band 24 rises. As a result, the surface roughness becomes large and the surface roughness ratio becomes large.

In the present embodiment, the roll may be rotated toward the opposite side with respect to the position of the release gas injection device as shown in FIG. 1, or the roll may be rotated toward the position of the release gas injection device as shown in FIG. Good. However, as shown in FIG. 1, it is preferable to rotate the roll toward the opposite side with respect to the position of the release gas injection device, and the temperature of the roll 23 is increased by further lengthening the time during which the roll 23 and the thin band 24 are in contact with each other. Even if the temperature is raised to about 50 to 90 ° C., the thin band 24 can be easily cooled rapidly. In the case of carrying out by the method shown in FIG. 1, the roll 23 and the thin band 24 are formed by changing the peeling gas injection pressure from the peeling gas injection device 26 as compared with the case of carrying out by the method shown in FIG. The effect of controlling the time of contact with and is great.

Further, when the temperature of the roll 23 is higher than before and the time during which the roll 23 and the thin band 24 are in contact with each other is further lengthened, the uniformity of the thin band 24 after cooling is increased and the particle size is increased. A crystal phase composed of crystals larger than 30 nm is less likely to occur. As a result, even if the composition is such that a crystal phase composed of crystals having a particle size larger than 30 nm is generated by the conventional method, a soft magnetic alloy strip containing no crystal phase composed of crystals having a particle size larger than 30 nm can be obtained. Then, it becomes easy to form a soft magnetic alloy strip having a structure consisting only of amorphous material or a nanoheterostructure in which initial microcrystals are present in amorphous metal.

In the single roll method, the thickness of the thin band 24 obtained mainly by adjusting the rotation speed of the roll 23 can be adjusted, but for example, the distance between the nozzle 21 and the roll 23 and the temperature of the molten metal can be adjusted. The thickness of the thin band 24 obtained by adjusting can also be adjusted. Further, even when the injection pressure is small, the thin band 24 may be formed by adjusting the distance between the nozzle 21 and the roll 23, the temperature of the molten metal, and the like.

The vapor pressure inside the chamber 25 is not particularly limited. For example, the vapor pressure inside the chamber 25 may be set to 11 hPa or less by using Ar gas having a dew point adjusted. There is no particular lower limit of the vapor pressure inside the chamber 25. The dew point-adjusted Ar gas may be filled to set the vapor pressure to 1 hPa or less, or the vapor pressure may be set to 1 hPa or less in a state close to vacuum.

The soft magnetic alloy strip 24 before heat treatment, which will be described later, does not contain crystals having a particle size larger than 30 nm. The soft magnetic alloy strip 24 before the heat treatment may have a structure consisting only of amorphous material, or may have a nanoheterostructure in which the initial microcrystals are present in the amorphous material.

There is no particular limitation on the method for confirming whether or not the thin band 24 contains crystals having a particle size larger than 30 nm. For example, the presence or absence of crystals having a particle size larger than 30 nm can be confirmed by ordinary X-ray diffraction measurement.

The presence or absence of the above initial microcrystals and the method of observing the average particle size are not particularly limited, but for example, a selected area diffraction image of a sample sliced by ion milling using a transmission electron microscope. It can be confirmed by obtaining a nanobeam diffraction image, a bright field image or a high resolution image. When a selected area diffraction image or a nanobeam diffraction image is used, ring-shaped diffraction is formed when the diffraction pattern is amorphous, whereas when it is not amorphous, diffraction spots due to the crystal structure are formed. It is formed. In the case of using a bright-field image or a high resolution image can be observed the presence and mean particle size of initial fine crystals by observing visually at a magnification 1.00 × 10 ⁵ ~3.00 × 10 ⁵ fold ..

Hereinafter, a method for producing a soft magnetic alloy strip having a structure composed of Fe-based nanocrystals by heat-treating the soft magnetic alloy strip 24 will be described. In the present embodiment, the structure composed of Fe-based nanocrystals is a structure composed of a crystal phase having an amorphization rate X of less than 85%. As described above, the amorphization rate X can be measured by performing X-ray crystal structure analysis by XRD.

The heat treatment conditions for producing the soft magnetic alloy strip of the present embodiment are not particularly limited. Preferred heat treatment conditions differ depending on the composition of the soft magnetic alloy strip. Generally, the preferable heat treatment temperature is about 450 to 650 ° C., and the preferable heat treatment time is about 0.5 to 10 hours. However, depending on the composition, there may be a preferable heat treatment temperature and heat treatment time outside the above range. Further, the atmosphere at the time of heat treatment is not particularly limited. It may be carried out in an active atmosphere such as in the air, or in an inert atmosphere such as in Ar gas.

Further, there is no particular limitation on the method of calculating the average particle size of the Fe-based nanocrystals contained in the soft magnetic alloy strip obtained by the heat treatment. For example, it can be calculated by observing with a transmission electron microscope. Further, there is no particular limitation on the method for confirming that the crystal structure is bcc (body-centered cubic lattice structure). For example, it can be confirmed by using X-ray diffraction measurement.

The surface roughness ratio of the soft magnetic alloy strip obtained by the heat treatment is within a predetermined range. The core obtained by winding a soft magnetic alloy strip having a surface roughness ratio within a predetermined range and the core obtained by laminating a soft magnetic alloy strip having a surface roughness ratio within a predetermined range are The space factor tends to be high, and the saturation magnetic flux density tends to be high. Therefore, a good core (particularly a toroidal core) can be obtained.

When the soft magnetic alloy strip having a structure composed of an amorphous phase is heat-treated to form a soft magnetic alloy strip composed of Fe-based nanocrystals, the surface roughness of the central portion of the peeled surface and the edge portion are affected. The surface roughness is reduced, and the surface roughness ratio is also reduced. Then, the space factor of the core using the soft magnetic alloy strip also increases. On the other hand, in the case of a soft magnetic alloy strip having a structure composed of an amorphous phase even after heat treatment, the surface roughness of the peeled surface hardly changes. Further, when crystals having a particle size larger than 30 nm are generated, the surface roughness of the central portion and the surface roughness of the edge portion of the peeled surface are reduced, but a soft magnetic alloy thin band composed of Fe-based nanocrystals is used. The amount of decrease is small compared to the case. Further, the effect of increasing the space factor of the core using the soft magnetic alloy strip is also small.

(Magnetic parts)
The magnetic components according to the present embodiment, particularly the core and the inductor, are obtained from the soft magnetic alloy strip according to the present embodiment. Hereinafter, the method for obtaining the core and the inductor according to the present embodiment will be described, but the method for obtaining the core and the inductor from the soft magnetic alloy strip is not limited to the following methods. In addition to inductors, core applications include transformers and motors.

Examples of the method of obtaining the core from the soft magnetic alloy strip include a method of winding the soft magnetic alloy strip and a method of laminating. When laminating the soft magnetic alloy strips via an insulator, a core having further improved characteristics can be obtained.

Further, an inductance component can be obtained by winding the above core. There are no particular restrictions on the winding method and the manufacturing method of the inductance component. For example, a method of winding the winding around the core manufactured by the above method for at least one turn or more can be mentioned.

Although each embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

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

(Experimental Example 1)
The raw material metal was weighed so as to have an alloy composition of _{Fe 0.84} Nb _0.07 B _{0.09 and melted by high frequency heating to prepare a mother alloy.}

Then, the prepared mother alloy was heated and melted to obtain a metal in a molten state at 1250 ° C., and then the roll was rotated at a rotation speed of 25 m / sec. The metal was injected onto the roll by the single roll method of rotating with, and a thin band was created. The material of the roll was Cu.

The roll was rotated in the direction shown in FIG. 1, and the roll temperature was set to the temperature shown in Table 1. The differential pressure (injection pressure) between the inside of the chamber and the inside of the injection nozzle was the pressure shown in Table 1. Further, by setting the slit width of the slit nozzle to 180 mm, the distance from the slit opening to the roll to 0.2 mm, and the roll diameter of φ300 mm, the thickness of the obtained thin band is 20 to 30 μm, and the length of the thin band is several tens. It was set to m.

Furthermore, it was confirmed whether the thin band before the heat treatment consisted of an amorphous phase or a crystalline phase. The amorphization rate X of each thin band was measured using XRD, and when X was 85% or more, it was determined to consist of an amorphous phase. When X was less than 85%, it was considered to consist of a crystalline phase .

Then, the thin strips of each Example and Comparative Example were heat-treated at 600 ° C. for 60 minutes.

The surface roughness (arithmetic mean roughness) of the peeled surface was measured for each thin band after the heat treatment. Moreover, the surface roughness ratio of the peeled surface was calculated by calculation. The surface roughness of the peeled surface was measured at three points each at the edge portion and the central portion by a contact type using a contact type surface roughness measuring instrument conforming to JIS-B0601, and the surface roughness of each was averaged. Furthermore, the surface roughness ratio was calculated.

Further, the surface roughness (maximum height roughness) of the free surface was measured for each thin band after the heat treatment. The surface roughness of the free surface was measured and averaged at three points in the central portion by a contact type using a contact type surface roughness measuring instrument conforming to JIS-B0601. In all the examples described in the present specification, the surface roughness of the free surface was 4.3 μm or less.

The coercive force and saturation magnetic flux density of each thin band after the heat treatment were measured. The coercive force was measured using (Hc meter). The saturation magnetic flux density was measured at a magnetic field of 1000 kA / m using a vibrating sample magnetometer (VSM). The coercive force is good at 12.0 A / m or less, further good at 5.0 A / m or less, further good at 2.5 A / m or less, particularly good at 2.0 A / m or less, and 1.5 A / m. The best was m or less. The saturation magnetic flux density was preferably 1.50 T or higher.

Unless otherwise specified, the thin bands of the examples shown below all had Fe-based nanocrystals having an average particle size of 5 to 30 nm and a crystal structure of bcc by X-ray diffraction measurement and. It was confirmed by observation using a transmission electron microscope. In addition, it was confirmed by ICP analysis that there was no change in the alloy composition before and after the heat treatment.

In addition, cores were made using the strips of each example and comparative example. First, a thin strip piece having a length of 310 mm in the casting direction was cut out from the thin strip. Next, 120 pieces of the cut out thin strip pieces were punched out in a toroidal shape having an outer diameter of 18 mm and an inner diameter of 10 mm, and the punched thin strip pieces were laminated to obtain a laminated toroidal core having a height of about 3 mm. No heat treatment was performed in a magnetic field when the core was manufactured.

The space factor of the core was obtained from the ratio of the dimensional density of the core to the Archimedes density of the thin band alone measured in advance. The saturation magnetic flux density of the core was measured with a BH analyzer. The space factor of the core was good at 85.00% or more, and further good at 87.50% or more. The saturation magnetic flux density of the core was set to 1.35 T or higher.

From Table 1, in each example in which the roll temperature is 50 ° C. or higher and 90 ° C. or lower and the injection pressure is 20 kPa or higher and 80 kPa or lower, the surface roughness ratio of the thin band is within the range of 0.85 to 1.25. The magnetic characteristics of the thin band became good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good.

On the other hand, in Sample 1 and Sample 2 in which the roll temperature was too low, the surface roughness ratio of the thin band was out of the range of 0.85 to 1.25, and the saturation magnetic flux density of the thin band decreased. Further, the space factor of the core produced by using the thin band also decreased, and the saturation magnetic flux density of the core further decreased.

(Experimental Example 2)
In Experimental Example 2, the raw metal was weighed so as to have the alloy composition of each Example and Comparative Example shown in the table below, and melted by high-frequency heating under the same conditions as in Experimental Example 1 except that a mother alloy was prepared. carried out. The roll temperature was 70 ° C. and the injection pressure was 50 kPa. The results are shown in Tables 2 to 22.

Tables 2 to 3 show Examples and Comparative Examples in which the M content (a) was changed. The type of M is Nb. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good. On the other hand, in the comparative example in which the M content (a) was too large, the saturation magnetic flux density of the thin band decreased, and the magnetic flux density of the core also decreased.

Tables 4 to 5 show Examples and Comparative Examples in which the B content (b) was changed. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good. On the other hand, in the comparative example in which the B content (b) was too small, the thin band before the heat treatment consisted of a crystalline phase, and the coercive force after the heat treatment became remarkably large. In addition, the surface roughness ratio was out of the range of 0.85 to 1.25, and the space factor of the core was also lowered. In the comparative example in which the B content was too large, the saturation magnetic flux density of the thin band decreased, and the magnetic flux density of the core also decreased.

Tables 6 to 7 show Examples and Comparative Examples in which the P content (c) was changed. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good. On the other hand, in the comparative example in which the P content (c) was too large, the saturation magnetic flux density of the thin band decreased, and the magnetic flux density of the core also decreased.

Tables 8 to 9 show Examples and Comparative Examples in which the C content (e) was changed. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good. On the other hand, in the comparative example in which the C content (e) was too large, the thin band before the heat treatment consisted of a crystalline phase, and the coercive force after the heat treatment became remarkably large.

Tables 10 to 11 show Examples and Comparative Examples in which the S content (f) was changed. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good. On the other hand, in the comparative example in which the C content (e) was too large, the thin band before the heat treatment consisted of a crystalline phase, and the coercive force after the heat treatment became remarkably large.

Tables 12 to 13 show examples in which the Si content (d) is changed. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good.

Tables 14 to 15 show Examples and Comparative Examples in which the Si content (d) was changed with the M content as 0. The sample 20 has not been heat-treated, and a Fe amorphous alloy strip having a conventionally known composition has been prepared. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good. On the other hand, the sample 20 had a higher coercive force than each thin band of the example.

Tables 16 to 17 describe examples in which the content (c) of P was changed with a composition in which the amount of Fe was large, the amount of B was small, and M was Zr as compared with the experimental examples shown in Tables 6 to 7. It is a thing. In each example in which the content of each component was within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good.

Table 18 shows examples in which the type of M is changed. In each example in which the type of M was changed to a predetermined type, the surface roughness ratio of the thin band was in the range of 0.85 to 1.25, and the magnetic characteristics of the thin band were good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good.

Tables 19 to 22 describe examples in which the types and contents of X1 and / or X2 are changed. In each example in which the types of X1 and / or X2 were changed to a predetermined type and the content was changed within a predetermined range, the surface roughness ratio of the thin band was within the range of 0.85 to 1.25. The magnetic characteristics of the thin band became good. Further, the space factor of the core produced by using the thin band was good, and the saturation magnetic flux density of the core was also good.

(Experimental Example 3)
For Sample 20 (Comparative Example) and Sample 39 (Example) of Experimental Example 2, changes in structure, surface roughness and coercive force before and after heat treatment were observed.

In Experimental Example 2, the sample 20 that had not been heat-treated was heat-treated at the heat treatment temperature and heat treatment time shown in Table 23. Then, the structure, surface roughness and coercive force when the heat treatment was performed were observed. The structure and surface roughness are shown in Table 23. In Table 23, it is assumed that the XRD measurement result after the heat treatment in the sample not subjected to the heat treatment is the same as the XRD measurement result before the heat treatment.

In Experimental Example 2, the structure, surface roughness, and coercive force of the heat-treated sample 39 were observed when the heat treatment was not performed. The structure and surface roughness are shown in Table 23. In Table 23, it is assumed that the XRD measurement result after the heat treatment in the sample not subjected to the heat treatment is the same as the XRD measurement result before the heat treatment.

As shown in Table 23, with respect to the sample 20 which does not contain M and the Si content (d) is outside the range of the present invention, the surface roughness of the sample 20a in which no crystals are generated even after the heat treatment is substantially changed. There wasn't. The coercive force was slightly reduced. Further, in the sample 20b in which the heat treatment temperature was higher than that in the sample 20a, crystals having a particle size larger than 30 nm (coarse) were present after the heat treatment. Then, the surface roughness of the central portion and the surface roughness of the edge portion were slightly reduced. The coercive force increased remarkably.

Therefore, in the sample 20 whose composition is outside the scope of the present invention, the surface roughness does not change and the coercive force is slightly reduced even after heat treatment, or large crystals are formed and the surface roughness is slight. Either the coercive force is significantly increased and the coercive force is significantly increased.

As shown in Table 23, the sample 39 before the heat treatment (sample 39a) and the sample 39 after the heat treatment are compared. When the composition is within a predetermined range, the heat treatment produces Fe-based nanocrystals having an average particle size of 5 to 30 nm and a crystal structure of bcc, the surface roughness of the central portion and the surface roughness of the edge portion are both after the heat treatment. It is significantly reduced compared to before heat treatment. The coercive force was also significantly reduced by the heat treatment. Therefore, it was found that the surface roughness is lowered and the coercive force is lowered due to the formation of Fe-based nanocrystals by the heat treatment. The surface roughness ratio also decreased. That is, the amount of decrease due to the heat treatment was slightly larger in the surface roughness of the edge portion than in the surface roughness of the central portion.

21 ... Nozzle 22 ... Molten metal 23 ... Roll 24 ... (Soft magnetic alloy) Thin band 24a ... Peeling surface 24b ... Free surface 25 ... Chamber 26 ... Peeling gas injection device 41 ... Edge part 43 ... Central part

Claims (11)

Composition formula (Fe _{(1- (α + β))} X1 _α X2 _β ) _{(1- (a + b + c + d + e + f))} M _a B _b P _c S _d C _{e S f} (atomic number ratio) And
X1 is one or more selected from the group consisting of Co and Ni,
X2 is one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements.
M is one or more selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V.
0 ≤ a ≤ 0.140
0.020 ≤ b ≤ 0.200
0.010 ≤ c ≤ 0.100
0 ≦ d ≦ 0.090
0 ≦ e ≦ 0.030
0 ≦ f ≦ 0.030
α ≧ 0
β ≧ 0
0 ≤ α + β ≤ 0.50
And
The content of elements other than the elements contained in the component is 0.1% by weight or less with respect to 100% by weight of the soft magnetic alloy strip.
The soft magnetic alloy strip has a structure composed of Fe-based nanocrystals, and has an amorphization rate X of less than 85%.
The soft magnetic alloy strip has a peeling surface and a free surface perpendicular to the thickness direction.
The soft magnetic alloy strip has an edge portion and a central portion along the width direction, and has an edge portion and a central portion.
The edge portion is a region where the distance from one edge is 0 to 20 mm.
The central portion is a region where the width of the soft magnetic alloy strip is L and the distances from both edges are both 3L / 8 to 5L / 8.
When the arithmetic mean roughness is measured along the width direction on the peeled surface, the average value of the arithmetic mean roughness in the central portion is defined as Ra _c , and the average value of the arithmetic mean roughness in the edge portion is defined as Ra _e .
0.85 ≤ Ra _e / Ra _c ≤ 1.25
Soft magnetic alloy strip that meets the requirements. The soft magnetic alloy strip according to claim 1, wherein the average particle size of the Fe-based nanocrystals is 5 to 30 nm. The soft magnetic alloy strip according to claim 1 or 2, wherein 0.73 ≦ 1- (a + b + c + d + e + f) ≦ 0.91. The soft magnetic alloy strip according to any one of claims 1 to 3, wherein 0 ≦ α {1- (a + b + c + d + e + f)} ≦ 0.40. The soft magnetic alloy strip according to any one of claims 1 to 4, wherein α = 0. The soft magnetic alloy strip according to any one of claims 1 to 5, wherein 0 ≦ β {1- (a + b + c + d + e + f)} ≦ 0.030. The soft magnetic alloy strip according to any one of claims 1 to 6, wherein β = 0. The soft magnetic alloy strip according to any one of claims 1 to 7, wherein α = β = 0. The soft magnetic alloy strip according to any one of claims 1 to 8, wherein the Ra _{c is 0.50 μm or less.} The soft magnetic alloy according to any one of claims 1 to 9, wherein the average value of the maximum height roughness is 4.3 μm or less when the maximum height roughness is measured along the casting direction on the free surface. Thin band. A magnetic component made of a soft magnetic alloy strip according to any one of claims 1 to 10.

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