Thin nanocrystal alloy band production method, and thin nanocrystal alloy band

Abstract

Provided are: a thin nanocrystal alloy band having excellent magnetic characteristics, and isotropy; and a production method for the thin nanocrystal alloy band. A method for producing a thin nanocrystal alloy band, the method comprising: thermally treating an thin alloy band represented by a composition formula (Fe1-xAx)aSibBcCudMe, where A represents at least one of Ni and Co, M represents one or more of Nb, Mo, V, Zr, Hf, and W, 81≤a≤86, 0.15≤b≤5.0, 12.5≤c≤15, 0≤d≤1.0, 0≤e≤1.0, and 0≤x≤0.1 are satisfied, wherein the alloy band, in a state of having a tension of 10-160 MPa applied thereto, is brought into contact with a heating body while being transported, and is subjected to the thermal treatment so that the temperature increase rate is at least 100 K / s, and the temperature Ta of the heating body is in the range of Tx1+85°C to Tx1+140°C when e<0.4 is satisfied in the composition formula and is in the range of Tx1+60°C to Tx1+100°C when e≥0.4 is satisfied in the composition formula, where Tx1 represents the crystallization temperature of the alloy band.

Description

Nanocrystalline alloy ribbon manufacturing method and nanocrystalline alloy ribbon

[0001] The present disclosure relates to a method for producing a nanocrystalline alloy ribbon having a nanocrystalline structure, and to a nanocrystalline alloy ribbon.

[0002] Nanocrystalline alloy ribbons having a nanocrystalline structure have excellent magnetic properties and are used in transformers, electronic components, motors, and the like. These transformers, electronic components, motors, and the like are required to be smaller and more efficient. To this end, further improvements in the properties of soft magnetic alloys used in the magnetic cores of these components (transformers, electronic components, motors, and the like) are required. The properties required of such soft magnetic alloys include high saturation magnetic flux density and low core loss (iron loss). As semiconductors and other devices become increasingly high-frequency, efforts are being made to increase the operating frequency of these components and thereby reduce their size. Fe-based amorphous alloys and Fe-based nanocrystalline alloys, which have low core loss, have attracted attention. To promote their commercial adoption, soft magnetic alloys with excellent cost, productivity, and heat treatability are required.

[0003] In Patent Document 1, the composition formula is Fe １００－ａ－ｂ－ｃ B ａ Cu ｂ M' ｃ The publication describes a method for producing a soft magnetic material that achieves both high saturation magnetization and low coercive force by heating an alloy having a composition that satisfies 10≦a≦16, 0<b≦2, and 0≦c≦8 and that has an amorphous phase at a heating rate of 10°C / sec or more and holding the temperature at a temperature above the crystallization start temperature and below the temperature at which an Fe-B compound is generated for 0 to 80 seconds.

[0004] In Patent Document 2, the composition formula ((Fe （１－（α＋β）） X1 α X2 β )(1-(a+b+c+d+e))B ａ Si ｂ C ｃ Cu ｄ M ｅThe soft magnetic alloy is characterized in that X1 is at least one element selected from the group consisting of Co and Ni, X2 is at least one element selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Bi, N, O, and rare earth elements, and M is at least one element selected from the group consisting of Nb, Hf, Zr, Ta, Ti, Mo, W, and V, and the following relationships are satisfied: 0.140<a≦0.240, 0≦b≦0.030, 0<c<0.080, 0<d≦0.020, 0≦e≦0.030, α≧0, β≧0, 0≦α+β≦0.50. The soft magnetic alloy is described as having high saturation magnetic flux density, low coercive force, and high magnetic permeability μ'.

[0005] In Patent Document 3, Fe １００－ｘ－ｙ―ｚ A ｘ M ｙ X ｚ where A is at least one element selected from Cu and Au, M is at least one element selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, and X is at least one element selected from B and Si, and the atomic percentages are 0<x≦5, 0.4≦y<2.5, and 10≦z≦20, and the saturation magnetic flux density of the soft magnetic alloy is 1.7 T or more and the coercive force is 15 A / m or less.

[0006] International Publication No. 2018 / 025931 Japanese Patent Application Laid-Open No. 2019-94532 International Publication No. 2008 / 133301

[0007] The soft magnetic material described in Patent Document 1 has a high saturation magnetization. However, the soft magnetic material described in Patent Document 1 does not contain Si, and therefore does not contain SiO, which contributes to the corrosion resistance of the soft magnetic material. ２ Since no film is formed on the surface of the material, it is difficult to prevent rust and other problems.

[0008] The soft magnetic alloy described in Patent Document 2 does not have a very high saturation magnetic flux density (Bs). Generally, the saturation magnetic flux density increases as the Fe content increases, but in Example 6, where the Fe content is 84 at %, the saturation magnetic flux density (Bs) is 1.76 T. In addition, the relatively high B content is thought to result in insufficient heat treatability.

[0009] The soft magnetic alloy described in Patent Document 3 is expensive because it contains a large amount of expensive M elements such as Nb. In addition, anisotropy is imparted in the casting direction, and the ratio of the magnetic flux density when a magnetic field of 80 A / m is applied in the casting direction to the magnetic flux density when a magnetic field of 80 A / m is applied in a direction perpendicular to the casting direction is large, making it unsuitable for applications requiring isotropy.

[0010] The nanocrystalline alloy ribbon is produced by ejecting a molten alloy adjusted to a predetermined alloy composition onto a rotating chill roll, rapidly solidifying the alloy ribbon, and then heat-treating the alloy ribbon. The nanocrystalline alloy ribbon is produced as a thin, long ribbon with a predetermined width. This production method easily introduces anisotropy in the casting direction (longitudinal direction), and even after heat treatment, the magnetic properties tend to differ between the longitudinal direction and the width direction perpendicular to the longitudinal direction.

[0011] For example, nanocrystalline alloy ribbons used in motors, etc., are required to have as isotropic properties as possible. However, as described above, it has been difficult to obtain a nanocrystalline alloy ribbon that has excellent magnetic properties (high saturation magnetic flux density, low iron loss) and isotropy.

[0012] An object of the present disclosure is to provide a method for manufacturing a nanocrystalline alloy ribbon that provides an isotropic nanocrystalline alloy ribbon having excellent magnetic properties. Another object of the present disclosure is to provide an isotropic nanocrystalline alloy ribbon having excellent magnetic properties.

[0013] The present disclosure has the following configuration: <1> Composition formula (Fe １－ｘ A ｘ ) ａ Si ｂ B ｃ Cu ｄ M ｅA method for producing a nanocrystalline alloy ribbon having a structure in which crystal grains having an average grain size of 30 nm or less exist in an amorphous phase by heat-treating an alloy ribbon represented by the formula (I), wherein A is at least one of Ni and Co, M is one or more selected from the group consisting of Nb, Mo, V, Zr, Hf, and W, and the contents thereof are, in atomic %, 81≦a≦86, 0.15≦b≦5.0, 12.5≦c≦15, 0≦d≦1.0, 0≦e≦1.0, and 0≦x≦0.1, the method comprising: applying a tension of 10 MPa to 160 MPa to the alloy ribbon; conveying the alloy ribbon while bringing the alloy ribbon into contact with a heater; and heat-treating the alloy ribbon so that the temperature rise rate of the alloy ribbon is 100 K / sec or more; The method for producing a nanocrystalline alloy ribbon according to <1>, wherein, when a crystallization temperature of the alloy ribbon is Tx1, the temperature Ta of the heater is in a range of Tx1+85°C to Tx1+140°C when e<0.4 in the composition formula, and in a range of Tx1+60°C to Tx1+100°C when e≥0.4 in the composition formula. <2> The method for producing a nanocrystalline alloy ribbon according to <1>, wherein the nanocrystalline alloy ribbon has a saturation magnetic flux density Bs of 1.6 T or more, and wherein, when a remanent magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in a longitudinal direction of the nanocrystalline alloy ribbon is LBr and a remanent magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in a width direction perpendicular to the longitudinal direction is WBr, LBr / WBr is 0.2 to 1.8. <3> The method for producing a nanocrystalline alloy ribbon according to <1> or <2>, wherein the nanocrystalline alloy ribbon has a maximum magnetic permeability μm of 4000 or more, and wherein, when the maximum magnetic permeability μm in the longitudinal direction of the nanocrystalline alloy ribbon (maximum measured magnetic field Hm=80 A / m) is L μm and the maximum magnetic permeability μm in the width direction perpendicular to the longitudinal direction (maximum measured magnetic field Hm=80 A / m) is W μm, L μm / W μm is 0.3 to 1.7.

[0014] <4> The anisotropic energy E (maximum measured magnetic field Hm=800 A / m) of the nanocrystalline alloy ribbon is 400 J / m ３<5> The method for producing a nanocrystalline alloy ribbon according to any one of <1> to <4>, wherein, when LE is an anisotropic energy E of the nanocrystalline alloy ribbon in a longitudinal direction (maximum measured magnetic field Hm=800 A / m) and WE is an anisotropic energy E in a width direction perpendicular to the longitudinal direction (maximum measured magnetic field Hm=800 A / m), LE / WE is 0.2 to 1.8. <6> The method for producing a nanocrystalline alloy ribbon according to any one of <1> to <4>, wherein a magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied is 0.4 T or more, and LB80 is the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied in the longitudinal direction, and WB80 is the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied in the width direction perpendicular to the longitudinal direction, and LB80 / WB80 is 0.3 to 1.7. <6> The method for producing a nanocrystalline alloy ribbon according to any one of <1> to <5>, wherein, during the heat treatment of the alloy ribbon, the temperature of the alloy ribbon is controlled so as not to exceed Ta + 50° C. <7> The method for producing a nanocrystalline alloy ribbon according to any one of <1> to <6>, wherein the heating body is composed of a plurality of heating parts with different temperatures, and the temperature of the heating part with the highest temperature among the plurality of heating parts is the temperature Ta.

[0015] <8> A nanocrystalline alloy ribbon having a structure in which crystal grains with an average grain size of 30 nm or less exist in an amorphous phase, the nanocrystalline alloy ribbon having a composition formula (Fe １－ｘ A ｘ ) ａ Si ｂ B ｃ Cu ｄ M ｅwherein A is at least one of Ni and Co, and M is one or more selected from the group consisting of Nb, Mo, V, Zr, Hf, and W, and the atomic percentages are 81≦a≦86, 0.15≦b≦5.0, 12.5≦c≦15, 0≦d≦1.0, 0≦e≦1.0, and 0≦x≦0.1; the saturation magnetic flux density Bs is 1.6 T or more; and the residual magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in the longitudinal direction of the nanocrystalline alloy ribbon is LBr, and the residual magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in the width direction perpendicular to the longitudinal direction is WBr, where LBr is the residual magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in the width direction perpendicular to the longitudinal direction. <9> The nanocrystalline alloy ribbon according to <8>, wherein the nanocrystalline alloy ribbon has a maximum magnetic permeability μm of 4000 or more, and wherein, when the maximum magnetic permeability μm in the longitudinal direction of the nanocrystalline alloy ribbon (maximum measured magnetic field Hm=80 A / m) is L μm and the maximum magnetic permeability μm in the width direction perpendicular to the longitudinal direction (maximum measured magnetic field Hm=80 A / m) is W μm, L μm / W μm is 0.3 to 1.7. <10> The nanocrystalline alloy ribbon has an anisotropic energy E (maximum measured magnetic field Hm=800 A / m) of 400 J / m ３ <11> The nanocrystalline alloy ribbon according to any one of <8> to <10>, wherein a magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto is 0.4 T or more, and wherein, when LB80 is the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto in the longitudinal direction and WB80 is the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto in the width direction orthogonal to the longitudinal direction, LB80 / WB80 is 0.3 to 1.7. <12> The nanocrystalline alloy ribbon according to any one of <8> to <11>, having a thickness of 15 μm or more and a width of 5 mm or more. <13> The nanocrystalline alloy ribbon according to any one of <8> to <12>, having a space factor of 86% or more. <14> The nanocrystalline alloy ribbon according to any one of <8> to <13>, having a saturation magnetostriction of 30 ppm or less.

[0016] According to the present disclosure, it is possible to provide a method for manufacturing a nanocrystalline alloy ribbon that can obtain a nanocrystalline alloy ribbon having excellent magnetic properties and isotropy. Also, it is possible to provide a nanocrystalline alloy ribbon having excellent magnetic properties and isotropy.

[0017] 1 is a diagram showing an example of an in-line annealing apparatus that can be used for the heat treatment of the present disclosure, and is a diagram plotting examples of the present disclosure and comparative examples, with the X axis representing Ta-Tx1 (°C) and the Y axis representing tension (MPa).

[0018] Hereinafter, embodiments of the present disclosure will be described in detail. The present disclosure is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present disclosure.

[0019] In the present disclosure, a numerical range indicated using "to" indicates a range that includes the numerical values ​​described before and after "to" as the lower and upper limits, respectively. In the numerical ranges described in stages in the present disclosure, the upper or lower limit described in a certain numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described in the present disclosure, the upper or lower limit described in a certain numerical range may be replaced with a value shown in the examples. In the present disclosure, a combination of two or more preferred aspects is a more preferred aspect.

[0020] The nanocrystalline alloy ribbon of the present disclosure has a composition formula (Fe １－ｘ A ｘ ) ａ Si ｂ B ｃ Cu ｄ M ｅ wherein A is at least one of Ni and Co, M is one or more selected from the group consisting of Nb, Mo, V, Zr, Hf, and W, and the atomic percentages are 81≦a≦86, 0.15≦b≦5.0, 12.5≦c≦15, 0≦d≦1.0, 0≦e≦1.0, and 0≦x≦0.1.

[0021] The composition of the nanocrystalline alloy ribbon of the present disclosure will be described in detail below. The Fe (iron) content is 81% or more and 86% or less in atomic percent. By setting the Fe content to 81% or more, a high saturation magnetic flux density can be obtained. The Fe content is preferably 82% or more, more preferably 82.5% or more, even more preferably 83% or more, even more preferably 83.5% or more, and even more preferably 84% or more. Furthermore, since it becomes difficult to form an amorphous structure when the Fe content exceeds 86%, the Fe content is set to 86% or less, and preferably 85.5% or less.

[0022] The content of Si (silicon) is 0.15% or more and 5.0% or less in atomic percent. By containing Si, SiO ２ This allows the formation of an oxide film of the above-mentioned Si. This improves the corrosion resistance of the nanocrystalline alloy ribbon. In order to obtain this effect of improving corrosion resistance, the Si content is set to 0.15% or more, preferably 1.0% or more. If the Si content exceeds 5.0%, it becomes difficult to obtain a high saturation magnetic flux density, and it also becomes difficult to increase the plate thickness of the alloy ribbon. For this reason, the Si content is set to 5.0% or less, preferably 4% or less, more preferably 3% or less, and even more preferably 2% or less.

[0023] The content of B (boron) is 12.5% ​​or more and 15% or less in atomic percent. Since it is difficult to form an amorphous phase when the B content is less than 12.5%, the B content is set to 12.5% ​​or more. It is preferably 13.0% or more, and more preferably 13.5% or more. When the B content exceeds 15%, the difference between the bccFe (αFe) crystallization onset temperature and the FeB precipitation onset temperature becomes small, narrowing the temperature range in which heat treatment is possible. This makes it difficult to obtain a uniform, fine nanocrystalline structure capable of achieving an iron loss of 25 W / kg or less at 1 T and 1 kHz. Therefore, the B content is set to 15% or less. It is preferably 14.5% or less, more preferably 14.4% or less, and even more preferably 14.0% or less.

[0024] The content of Cu (copper) is 0% or more and 1.0% or less in atomic percent. The Cu content may be 0%, but adding Cu makes it easier to obtain a uniform and fine nanocrystalline structure. In particular, adding Cu is preferable to achieve low iron loss. For this reason, the Cu content is preferably 0.05% or more. More preferably, it is 0.1% or more, even more preferably 0.2% or more, even more preferably 0.4% or more, and even more preferably 0.5% or more. If the Cu content exceeds 1.0%, the nanocrystalline alloy ribbon becomes easily embrittled, making it difficult to increase the thickness of the ribbon. For this reason, the Cu content is set to 1.0% or less. It is preferably 0.9% or less, even more preferably 0.85% or less, even more preferably 0.7% or less, and even more preferably 0.6% or less.

[0025] The M element is one or more elements selected from the group consisting of Nb, Mo, V, Zr, Hf, and W, and is present in an atomic percentage range of 0% to 1.0%. While the M element may be 0%, the inclusion of the M element can shift the precipitation start temperature of FeB compounds, which significantly degrade soft magnetic properties, to a higher temperature. This widens the difference between the bccFe (αFe) crystallization start temperature (also known as the crystallization temperature) and the FeB precipitation start temperature, thereby widening the optimal heat treatment temperature range and easing the heat treatment conditions. The M element is preferably present in an amount of 0.1% or more, and more preferably 0.15% or more. The M element is expensive, which increases the price. Therefore, a lower content is preferable. Therefore, the M element content is set to 1.0% or less. It is preferably present in an amount of 0.9% or less, more preferably 0.8% or less, even more preferably 0.7% or less, and even more preferably 0.6% or less. The M element content is also preferably less than 0.4%, more preferably 0.3% or less, and even more preferably 0.25% or less.

[0026] In the nanocrystalline alloy ribbon of the present disclosure, a portion of Fe may be substituted with at least one element selected from Ni and Co. (Fe １－ｘ A ｘ ), A is at least one of Ni and Co, and x is 0.1 or less.

[0027] The nanocrystalline alloy ribbon of the present disclosure may contain C (carbon), preferably 1 mass % or less.

[0028] Furthermore, the nanocrystalline alloy ribbon of the present disclosure may contain impurities other than the elements described above. Examples of impurities include S (sulfur), O (oxygen), N (nitrogen), Cr, Mn, P, Ti, and Al. For example, the S content is preferably 200 mass ppm or less, the O content is preferably 5000 mass ppm or less, and the N content is preferably 1000 mass ppm or less. The total content of these impurities is preferably 0.5 mass% or less. Furthermore, elements corresponding to the impurities may be added as long as they are within the above ranges.

[0029] The nanocrystalline alloy ribbon of the present disclosure has a structure in which crystal grains with an average grain size of 30 nm or less exist in an amorphous phase. This structure in which crystal grains with an average grain size of 30 nm or less exist in an amorphous phase is also called a nanocrystalline structure. The average grain size was calculated from the Scherrer equation using the full width at half maximum of the diffraction peak from the (110) plane in an X-ray diffraction pattern obtained from an X-ray diffraction experiment. The full width at half maximum of the (110) peak was calculated by peak resolution using a pseudo-Voigt function for the diffraction pattern. Given that the average grain size is D, the full width at half maximum is W, the diffraction angle is θ, the Scherrer constant is K, and the X-ray wavelength is λ, D can be calculated from the Scherrer equation (Equation 1) given below. In this case, the X-ray wavelength λ was assumed to be 0.154050 nm and the Scherrer constant K was assumed to be 0.891.

[0030]

[0031] A method for producing a nanocrystalline alloy ribbon according to the present disclosure will be described. The nanocrystalline alloy ribbon according to the present disclosure can be obtained by ejecting a molten alloy having the above-described alloy composition onto a rotating chill roll, rapidly solidifying the alloy ribbon on the chill roll, and heat-treating the alloy ribbon. The alloy ribbon obtained by rapidly solidifying the molten alloy is in an amorphous state, becoming an amorphous alloy ribbon. The amorphous alloy ribbon (amorphous alloy ribbon) is heat-treated to obtain a nanocrystalline alloy ribbon. The amorphous alloy ribbon may have a crystalline phase consisting of fine crystals.

[0032] The molten alloy can be prepared by blending the element sources (pure iron, ferroboron, ferrosilicon, etc.) that will result in the desired alloy composition, heating them in an induction heating furnace, and melting them above their melting points. The molten alloy is ejected onto a rotating chill roll from a slit-shaped nozzle of a predetermined shape, and the molten alloy is rapidly solidified on the chill roll to obtain an alloy ribbon. The chill roll can have an outer diameter of 350 to 1,000 mm, a width of 100 to 400 mm, and a peripheral speed of rotation of 20 to 35 m / s. The chill roll is internally equipped with a cooling mechanism (e.g., water cooling) to suppress temperature increases at the outer periphery. The outer periphery of the chill roll is preferably made of a Cu alloy with a thermal conductivity of 120 W / (m·K) or higher. By ensuring that the thermal conductivity of the outer periphery is 120 W / (m·K) or higher, the cooling rate of the molten alloy when cast into an alloy ribbon can be increased. This suppresses embrittlement of the alloy ribbon, enabling the alloy ribbon to be thickened, and also suppresses surface crystallization during casting, thereby suppressing coarsening of crystal grains during heat treatment and reducing iron loss.

[0033] The thermal conductivity of the outer periphery is preferably 150 W / (m K) or more, and more preferably 180 W / (m K) or more. In particular, when the thickness of the nanocrystalline alloy ribbon is 30 μm or more, the thermal conductivity of the outer periphery is preferably 150 W / (m K) or more. The outer periphery of the chill roll is the portion that comes into contact with the molten alloy, and its thickness may be about 5 to 15 mm, and the inside thereof may be made of a structural material that maintains the roll structure.

[0034] A nanocrystalline alloy ribbon is obtained by heat-treating the alloy ribbon produced by the above-described quenching method. The method for producing a nanocrystalline alloy ribbon according to the present disclosure is characterized by the heat-treatment method. In the heat-treatment method according to the present disclosure, the alloy ribbon is conveyed while applying a tension of 10 MPa to 160 MPa to the alloy ribbon, and the alloy ribbon is brought into contact with a heating body, and heat-treated so that the temperature rise rate of the alloy ribbon is 100 K / sec or more. When the crystallization temperature of the alloy ribbon is Tx1, the temperature Ta of the heating body is in the range of Tx1 + 85°C to Tx1 + 140°C when e<0.4 in the composition formula, and in the range of Tx1 + 60°C to Tx1 + 100°C when e≧0.4 in the composition formula. In the present disclosure, the crystallization temperature of the alloy ribbon refers to the crystallization start temperature of bccFe (αFe).

[0035] In the heat treatment method disclosed herein, the alloy ribbon is conveyed under tension and heated by contacting it with a heater. The tension, heater temperature, and heating rate of the alloy ribbon are important factors in this process. By appropriately setting the tension, heater temperature, and heating rate of the alloy ribbon, it is possible to obtain a nanocrystalline alloy ribbon that has excellent magnetic properties (high saturation magnetic flux density, low core loss) and isotropy.

[0036] In the present disclosure, the effect of obtaining isotropic magnetic properties can be expected by applying tension and performing heat treatment at a fast temperature increase rate. The tension is set to 10 MPa to 160 MPa, preferably 30 MPa or more, more preferably 34 MPa or more, and preferably 150 MPa or less, more preferably 145 MPa or less.

[0037] In the present disclosure, it has been found that the preferred temperature range of the heater temperature Ta varies depending on the composition. It has also been found that the heater temperature Ta can be set by a relational expression with the crystallization temperature Tx1 of the alloy ribbon (the crystallization onset temperature of bccFe (αFe)). When e<0.4 in the composition formula, the heater temperature Ta is set in the range of Tx1+85°C to Tx1+140°C. It is preferably Tx1+90°C or higher, more preferably Tx1+95°C or higher. It is preferably Tx1+120°C or lower, more preferably Tx1+115°C or lower. Furthermore, when e≧0.4 in the composition formula, the heater temperature Ta is set in the range of Tx1+60°C to Tx1+100°C. When a lower temperature range is selected within this temperature range, it may be preferable to extend the contact time of the alloy ribbon with the heater.

[0038] [Crystallization Temperature (Crystallization Start Temperature of bccFe (αFe)) Tx1, FeB Precipitation Start Temperature Tx2] When a nanocrystalline alloy ribbon is obtained by heat-treating an alloy ribbon, the FeB precipitation start temperature Tx2 exists at a temperature higher than the crystallization temperature. If the alloy ribbon reaches the FeB precipitation start temperature, the crystals become coarse and FeB, which deteriorates the magnetic properties, precipitates. Therefore, the heat treatment must be performed so that the temperature does not reach the FeB precipitation start temperature. The crystallization temperature and FeB precipitation start temperature of the alloy ribbon can be obtained as follows. The crystallization temperature and FeB precipitation start temperature vary depending on the heating rate. However, the upper limit of the heating rate of a general thermal analyzer is about 2° C. / sec, which makes it impossible to measure the heating rate during the heat treatment of the present disclosure. Therefore, values ​​at a heating rate of 50° C. / sec were determined as the crystallization temperature and FeB precipitation start temperature by the following method. Using a Rigaku DSC8231 differential scanning calorimeter, the crystallization temperature and the FeB precipitation start temperature were measured at three heating rates of 5°C / min (0.083°C / sec), 20°C / min (0.333°C / sec), and 50°C / min (0.833°C / sec). The values ​​were plotted with the logarithm of the heating rate on the X axis and the crystallization temperature or the FeB precipitation start temperature on the Y axis, and the value at a heating rate of 50°C / sec was extrapolated from the approximation curve.

[0039] In the present disclosure, the heating rate of the alloy ribbon is set to 100 K / sec or more. This heating rate was calculated by determining the slope of the tangent near the heat treatment temperature Ta during heating. It is preferably 300 K / sec or more, more preferably 500 K / sec or more. The upper limit may be set within the range possible depending on the equipment and process conditions. For example, it can be set to 4000 K / sec or less. It is preferably 3000 K / sec or less, more preferably 2500 K / sec or less.

[0040] In the present disclosure, the alloy ribbon is heat-treated while being transported. The alloy ribbon is formed into a long length, and by carrying out the heat treatment while being transported, the long alloy ribbon can be efficiently heat-treated. In the present disclosure, the contact time between the alloy ribbon and the heating body is preferably 0.5 seconds to 60 seconds. In the present disclosure, the transport speed of the alloy ribbon is preferably 3 m / min to 300 m / min, and more preferably 200 m / min or less.

[0041] In the present disclosure, the heater may be composed of a plurality of heating parts with different temperatures. In this case, the temperature of the heating part with the highest temperature among the plurality of heating parts is defined as the temperature Ta.

[0042] The alloy ribbon may generate heat by itself due to crystallization during heat treatment. As described above, if the temperature of the alloy ribbon reaches the FeB precipitation start temperature, the desired magnetic properties of the nanocrystalline alloy ribbon cannot be obtained. Furthermore, even if the temperature does not reach the FeB precipitation start temperature, if the temperature rises too much, the growth of the crystal grain size is accelerated, resulting in deterioration of iron loss. In the present disclosure, when there is no temperature rise due to self-heating, the heating temperature of the alloy ribbon reaches a maximum temperature Ta of the heater. In contrast, when there is a temperature rise due to self-heating, the heating temperature of the alloy ribbon exceeds the temperature Ta of the heater. In this case, it is preferable to suppress an excessive temperature rise. In the present disclosure, it is preferable to control the temperature of the alloy ribbon due to the temperature rise due to self-heating so that it does not exceed Ta + 50°C.

[0043] The method for heat-treating the alloy ribbon by conveying the alloy ribbon under tension and bringing it into contact with a heater can be based on the method for manufacturing an amorphous alloy ribbon disclosed in International Publication No. WO2019 / 009309. The in-line annealing apparatus described in International Publication No. WO2019 / 009309 is shown in Figure 1.

[0044] The heat treatment of the present disclosure can use, for example, an in-line annealing apparatus shown in Fig. 1. The in-line annealing apparatus 100 shown in Fig. 1 includes an unwinding roller 12 (unwinding device) that unwinds the alloy ribbon 10 from a wound body 11 of the alloy ribbon, a heating element (heating plate) 22 that heats the alloy ribbon 10 unwound from the unwinding roller 12, a cooling plate 32 that cools the alloy ribbon 10 heated by the heating element 22, and a winding roller 14 (winding device) that winds up the alloy ribbon 10 that has been cooled by the cooling plate 32. In Fig. 1, the running direction of the alloy ribbon 10 is indicated by an arrow R.

[0045] As shown in the enlarged circled portion in FIG. 1 , the heating element 22 includes a first plane 22S on which the alloy ribbon 10 unwound from the unwind roller 12 runs while contacting the first plane 22S. The heating element 22 heats the alloy ribbon 10 running on the first plane 22S while contacting the first plane 22S via the first plane 22S. This allows the running alloy ribbon 10 to be stably and rapidly heated. The heating element 22 may be a combination of multiple heating units that can be set to different temperatures, or may have a configuration in which the above-mentioned first plane 22S portion is integrated but can be set to multiple heating temperatures. In this way, the heating element can be configured from multiple heating units.

[0046] The heating element 22 is housed in the heating chamber 20. The heating chamber 20 may be equipped with a heat source for controlling the temperature of the heating chamber, separate from the heat source for the heating element 22. In the in-line annealing apparatus shown in FIG. 1 , as shown in the enlarged circled area, the cooling plate 32 includes a second flat surface 32S on which the alloy ribbon 10 runs while contacting it. The cooling plate 32 lowers the temperature of the alloy ribbon 10 running on the second flat surface 32S while contacting the second flat surface 32S, via the second flat surface 32S. The cooling plate 32 is housed in the cooling chamber 30.

[0047] The winding roller 14 is equipped with a rotation mechanism (for example, a motor) that rotates about its axis in the direction of arrow W. The rotation of the winding roller 14 causes the alloy ribbon 10 to be wound at a desired speed.

[0048] The in-line annealing apparatus 100 is provided with a guide roller 41, a dancer roller 60 (one of the tension adjusting devices), a guide roller 42, and a pair of guide rollers 43A and 43B, along the travel path of the alloy ribbon 10, between the unwinding roller 12 and the heating chamber 20. Tension adjustment is also performed by controlling the operation of the unwinding roller 12 and the take-up roller 14. The dancer roller 60 is provided so as to be movable in the vertical direction (the direction of the double-sided arrow in FIG. 1 ). The tension of the alloy ribbon 10 can be adjusted by adjusting the position of this dancer roller 60 in the vertical direction (the direction of the double-sided arrow). The same applies to the dancer roller 62.

[0049] A plurality of openings may be provided in the first plane of the heating element 22 to allow for suction, thereby improving the adhesion between the alloy ribbon and the heating element. Examples of materials for the heating element include copper, copper alloys (bronze, brass, etc.), aluminum, iron, and iron alloys (stainless steel, etc.). Of these, copper, copper alloys, and aluminum are preferred because they have a high thermoelectric coefficient (heat transfer coefficient). The heating element may be plated with Ni, Ag, or the like.

[0050] The nanocrystalline alloy ribbon according to the present disclosure is obtained by the above-described production method, has the above-described composition, and is provided with excellent magnetic properties and isotropy. The nanocrystalline alloy ribbon according to the present disclosure is a nanocrystalline alloy ribbon having a structure in which crystal grains having an average grain size of 30 nm or less exist in an amorphous phase, and has a saturation magnetic flux density Bs of 1.6 T or more. When LBr is the residual magnetic flux density Br (maximum measured magnetic field Hm = 80 A / m) in the longitudinal direction of the nanocrystalline alloy ribbon and WBr is the residual magnetic flux density Br (maximum measured magnetic field Hm = 80 A / m) in the width direction perpendicular to the longitudinal direction, LBr / WBr is 0.2 to 1.8. LBr / WBr is preferably 0.4 to 1.6, more preferably 0.6 to 1.4, and even more preferably 0.8 to 1.2.

[0051] Furthermore, the nanocrystalline alloy ribbon of the present disclosure preferably has an iron loss of 25 W / kg or less at 1 kHz and 1 T, more preferably 20 W / kg or less, and even more preferably 15 W / kg or less. Furthermore, the saturation magnetic flux density Bs is preferably 1.65 T or more, more preferably 1.7 T or more, and even more preferably 1.75 T or more.

[0052] Furthermore, the nanocrystalline alloy ribbon of the present disclosure has a maximum magnetic permeability μm of 4000 or more, and when the maximum magnetic permeability μm in the longitudinal direction of the nanocrystalline alloy ribbon (maximum measured magnetic field Hm=80 A / m) is L μm and the maximum magnetic permeability μm in the width direction perpendicular to the longitudinal direction (maximum measured magnetic field Hm=80 A / m) is W μm, the ratio L μm / W μm is preferably 0.3 to 1.7, more preferably 0.6 to 1.4, and even more preferably 0.8 to 1.2.

[0053] Furthermore, the nanocrystalline alloy ribbon of the present disclosure has an anisotropic energy E (maximum measured magnetic field Hm=800 A / m) of 400 J / m ３ When the anisotropic energy E (maximum measured magnetic field Hm=800 A / m) in the longitudinal direction of the nanocrystalline alloy ribbon is LE and the anisotropic energy E (maximum measured magnetic field Hm=800 A / m) in the width direction perpendicular to the longitudinal direction is WE, the ratio LE / WE is preferably 0.2 to 1.8, more preferably 0.4 to 1.6, still more preferably 0.6 to 1.4, and still more preferably 0.8 to 1.2.

[0054] Furthermore, the nanocrystalline alloy ribbon of the present disclosure has a magnetic flux density B80 of 0.4 T or more when a magnetic field of 80 A / m is applied thereto, and when the magnetic flux density B80 when a magnetic field of 80 A / m is applied in the longitudinal direction of the nanocrystalline alloy ribbon is defined as LB80 and the magnetic flux density B80 when a magnetic field of 80 A / m is applied in the width direction perpendicular to the longitudinal direction is defined as WB80, the ratio LB80 / WB80 is preferably 0.3 to 1.7, more preferably 0.6 to 1.4, and even more preferably 0.8 to 1.2.

[0055] Furthermore, the nanocrystalline alloy ribbon of the present disclosure preferably has a thickness of 15 μm or more. More preferably, it is 30 μm or more. A thickness of 15 μm or more can reduce the number of steps and manufacturing costs when laminating nanocrystalline alloy ribbons to produce a magnetic core. A thickness of 32 μm or more is even more preferable. Furthermore, for applications requiring lower iron loss in a high frequency band exceeding 1 kHz, a ribbon with a thickness of approximately 15 to 25 μm is preferable. Furthermore, a width of 5 mm or more is preferable. The width is more preferably 10 mm or more, more preferably 100 mm or more, and even more preferably 200 mm or more.

[0056] Furthermore, the nanocrystalline alloy ribbon of the present disclosure preferably has a space factor of 86% or more. Furthermore, the space factor is preferably 88% or more, and more preferably 90% or more. Due to the high space factor, when soft magnetic alloy ribbons are stacked, the lamination thickness can be thinner compared to alloy ribbons with a low space factor, even with the same number of layers, contributing to the miniaturization of magnetic cores and components. The space factor can be measured by the following method in accordance with JIS C 2534:2017. Twenty ribbons cut to a length of 120 mm are stacked and placed on a flat sample stage. A flat anvil with a diameter of 16 mm is placed on the stacked ribbons under a pressure of 50 kPa, and the height is measured at 10 mm intervals in the width direction. The maximum height at this time is defined as hmax (μm), and the space factor LF is calculated using the following formula: LF (%) = sample weight (g) / density (g / cm ３ ) / hmax (μm) / sample length (240 cm) / ribbon width (cm) × 10000 At this time, density (g / cm ３ ) is the density of the alloy ribbon after heat treatment, and is 7.5 g / cm 3In addition, it is preferable that the saturation magnetostriction is 30 ppm or less.

[0057] The nanocrystalline alloy ribbon of the present disclosure can be used to form magnetic cores for transformers, electronic components, motors, and the like, thereby obtaining magnetic cores with excellent properties. When forming a magnetic core, the alloy ribbon can be cut into a predetermined shape and stacked, wound, or stacked and bent. Furthermore, by combining the magnetic core of the present disclosure with a winding to form a component such as a transformer, electronic component, or motor, a component with excellent properties can be obtained. In this case, the magnetic core of the present disclosure may be combined with a magnetic core made of another magnetic material.

[0058] Example 1: Element sources were blended to obtain the compositions shown in Table 1 and heated to 1,300°C to prepare molten alloys. The molten alloys were then ejected onto a chill roll with an outer diameter of 400 mm and a width of 200 mm, rotating at a peripheral speed of 30 m / s, and rapidly solidified on the chill roll to produce alloy ribbons. The outer periphery of the chill roll was made of a Cu alloy with a thermal conductivity of 150 W / (m·K), and the chill roll was equipped with an internal cooling mechanism for controlling the temperature of the outer periphery. The produced alloy ribbons were in an amorphous state and were amorphous alloy ribbons. For each material, the crystallization temperature (crystallization onset temperature of bccFe (αFe)) Tx1 and the FeB precipitation onset temperature Tx2 were measured using the method described above, and the results are shown in Table 1.

[0059] Using alloy ribbons of each material, heat treatment was performed by changing the tension, the temperature Ta of the heater, and the contact time with the heater. The conditions and evaluation results are shown in Tables 2, 3, and 4. The alloy ribbons after the heat treatment were nanocrystalline alloy ribbons having a structure in which crystal grains with an average grain size of 30 nm or less existed in an amorphous phase.

[0060] For each sample, iron loss, saturation magnetic flux density Bs, residual magnetic flux density Br, magnetic flux density B80, maximum magnetic permeability μm, anisotropy energy, and coercive force Hc were measured.

[0061] [Iron Loss] The heat-treated single sheet sample was measured using an AC magnetic measuring device TWM18SR manufactured by Toei Kogyo under the conditions of a magnetic flux density of 1 T and a frequency of 1 kHz.

[0062] [Saturation Magnetic Flux Density Bs] A magnetic field of 8000 A / m is applied to the heat-treated single sheet sample using a DC magnetization characteristic tester manufactured by Metron Giken, and the maximum magnetic flux density at that time is measured and designated as Bs. The nanocrystalline alloy ribbon of the present disclosure has a property that is relatively prone to saturation, and therefore is saturated at the time when a magnetic field of 8000 A / m is applied, and B ８０００ Since the saturation magnetic flux density Bs is almost the same as B ８０００ It is expressed as:

[0063] [Residual magnetic flux density Br] Using a DC magnetization characteristic tester manufactured by Metron Giken, a magnetic field of 80 A / m was applied to a nanocrystalline alloy ribbon, and then the magnetic field was gradually weakened until the applied magnetic field reached 0 A / m, and the magnetic flux density was defined as the residual magnetic flux density Br. Furthermore, a magnetic field of 80 A / m was applied to the nanocrystalline alloy ribbon in the longitudinal direction (casting direction) and in the width direction perpendicular to the longitudinal direction, and then the magnetic flux densities when the applied magnetic field reached 0 A / m were defined as LBr and WBr, respectively, and the ratio LBr / WBr was calculated to evaluate isotropy.

[0064] [Magnetic Flux Density B80] A magnetic field of 80 A / m was applied to the nanocrystalline alloy ribbon using a DC magnetization characteristic tester manufactured by Metron Giken Co., Ltd., and the maximum magnetic flux density at this time was defined as B80. In addition, a magnetic field of 80 A / m was applied to the nanocrystalline alloy ribbon in the longitudinal direction (casting direction) and in the width direction perpendicular to the longitudinal direction, and the maximum magnetic flux densities at this time were defined as LB80 and WB80, respectively, and the ratio LB80 / WB80 was calculated to evaluate isotropy.

[0065] [Maximum magnetic permeability μm] A magnetic field of up to 80 A / m was applied to a nanocrystalline alloy ribbon using a DC magnetization characteristic tester manufactured by Metron Giken Co., Ltd., and the maximum value of the quotient of the magnetic flux density and the magnetic field at that time was defined as the maximum magnetic permeability μm. The maximum magnetic permeabilities measured in the longitudinal direction (casting direction) and in the width direction perpendicular to the longitudinal direction were defined as L μm and W μm, respectively, and the ratio L μm / W μm was calculated to evaluate isotropy.

[0066] [Anisotropic Energy] A magnetic field of up to 800 A / m was applied to a nanocrystalline alloy ribbon using a DC magnetization property tester manufactured by Metron Giken. The anisotropic energy E was determined by subtracting the area of ​​the magnetic flux density-magnetic field curve from the product of the maximum magnetic flux density and the maximum measured magnetic field at that time. The anisotropic energies measured in the longitudinal direction (casting direction) and the width direction perpendicular to the longitudinal direction were defined as L and W, respectively, and the ratio L / W was calculated to evaluate isotropy.

[0067] [Coercive force Hc] A magnetic field of 8000 A / m was applied to the nanocrystalline alloy ribbon in the longitudinal direction (casting direction) using a DC magnetization characteristic tester manufactured by Metron Giken, and then the magnetic field was gradually weakened until the magnetic flux density reached 0 T, which was taken as the coercive force.

[0068]

[0069]

[0070]

[0071]

[0072] In Tables 2 and 3, for materials A, B, D, and G, which are materials with a composition formula of e<0.4, samples with an LBr / WBr ratio in the range of 0.2 to 1.8 are designated as Examples, and samples outside this range are designated as Comparative Examples. Figure 2 shows a plot of Examples and Comparative Examples, with ● representing Examples and ▲ representing Comparative Examples, with Ta-Tx1 (°C) on the X axis and tension (MPa) on the Y axis. As shown in Figure 2, when Ta-Tx1 is 81°C or less, it is designated as Comparative Examples, and when it is above 81°C, it is designated as Examples. Therefore, when e<0.4 in the composition formula, it is clear that a highly isotropic nanocrystalline alloy ribbon can be obtained by setting the tension to 10 MPa to 160 MPa and setting the heater temperature Ta in the range of Tx1+85°C to Tx1+140°C.

[0073] In this case, in the above example, L μm / W μm is in the range of 0.3 to 1.7, LE / WE is in the range of 0.2 to 1.8, and LB80 / WB80 is in the range of 0.3 to 1.7.

[0074] In Tables 2 and 3, for materials C, E, and F, which are materials with a composition formula of e≧0.4, good values ​​were obtained when Ta−Tx1 was 77°C, 81°C, and 83°C. When e≧0.4 in the composition formula, it can be seen that a highly isotropic nanocrystalline alloy ribbon can be obtained by setting the tension to 10 MPa to 160 MPa and the heater temperature Ta in the range of Tx1+60°C to Tx1+100°C. At this time, the heating rate was 100 K / sec or more. In the above example, Lμm / Wμm was in the range of 0.3 to 1.7. Also, LE / WE was in the range of 0.2 to 1.8. Also, LB80 / WB80 was in the range of 0.3 to 1.7.

[0075] Furthermore, as shown in Table 4, the nanocrystalline alloy ribbons according to the examples of the present disclosure have an iron loss of 10 W / kg or less, and thus have low-loss nanocrystalline alloy ribbons with an iron loss of 25 W / kg or less. Furthermore, the nanocrystalline alloy ribbons have a saturation magnetostriction of 15 ppm or less, and thus have saturation magnetostriction of 30 ppm or less.

[0076] [Saturation magnetostriction] The saturation magnetostriction was measured by applying a 5 kOe magnetic field to a sample with a strain gauge attached by Kyowa Electric Industrial Co., Ltd., rotating the electromagnet by 360° and changing the direction of the magnetic field applied to the sample by 360°. The maximum change in the elongation and contraction of the sample was measured from the change in the electrical resistance of the strain gauge. Saturation magnetostriction = ⅔ × maximum change.

[0077] Table 4 shows the self-heating. This self-heating is the temperature rise (temperature of the alloy ribbon - Ta) that exceeds the heating temperature (temperature of the heater Ta) due to heat generation during crystallization of the alloy ribbon. According to the examples of the present disclosure, the self-heating can be controlled to a range not exceeding Ta + 50°C.

[0078] Example 2 A nanocrystalline alloy ribbon was produced in the same manner as in Example 1 using materials B and G shown in Table 1. Table 5 shows the tension, the temperature Ta of the heater, the heating rate of the ribbon, the contact time with the heater, the crystalline volume fraction, and the average grain size. Here, the average grain size refers to the average grain size of the nanocrystals. The average grain size of the nanocrystals was calculated using the Scherrer formula (Mathematical Formula 1) described above. In the examples of the present disclosure, it can be seen that the average grain size is 30 nm or less. Therefore, the nanocrystalline alloy ribbon of the present disclosure has a structure in which crystal grains with an average grain size of 30 nm or less exist in an amorphous phase.

[0079] In Table 5, the crystalline volume fraction is the volume fraction of crystal grains (nanocrystals) with an average particle size of 30 nm or less. The portion other than the nanocrystals is amorphous. The crystalline volume fraction is the ratio of the integrated intensity of the nanocrystals to the integrated intensity of (crystalline + amorphous). The integrated intensities of the peaks exhibited by the nanocrystals and the halo patterns exhibited by the amorphous phase are determined by peak resolution using a pseudo-Voigt function for the X-ray diffraction pattern. If the total integrated intensity of all peaks exhibited by the nanocrystals is Ic and the total integrated intensity of all halo patterns exhibited by the amorphous phase is Ia, the volume fraction V can be determined from the following equation (Equation 2).

[0080]

[0081]

[0082] As shown in Table 5, the heating rate of each sample was 100 K / sec or more.

[0083] Example 3 Nanocrystalline alloy ribbons were produced in the same manner as in Example 1, using material B shown in Table 1. In this example, the heater had a structure having two heating portions. For example, the heater (heating plate) 22 shown in FIG. 1 had a structure capable of setting two temperatures, with the temperature of the first portion set to T1 and the second temperature set to T2. The higher of T1 and T2 was set to Ta. Table 6 shows the tension of each sample, the heater temperatures T1, T2, and Ta, and the conveying speed of the alloy ribbon. Table 7 shows the properties of each sample produced under these conditions. When a nanocrystalline alloy ribbon was produced using a heater with a structure having multiple heating portions, a nanocrystalline alloy ribbon with higher isotropy was obtained.

[0084]

[0085]

[0086] As described above, according to the present disclosure, a method for manufacturing a nanocrystalline alloy ribbon that has excellent magnetic properties and isotropy can be obtained, and a nanocrystalline alloy ribbon that has excellent magnetic properties and isotropy can be obtained.

Claims

1. A method for producing a nanocrystalline alloy ribbon having a structure in which crystal grains having an average grain size of 30 nm or less are present in an amorphous phase, by heat treating an alloy ribbon represented by a composition formula of (Fe1-xAx)aSibBcCudMe, A being at least one of Ni and Co, and M being at least one selected from the group consisting of Nb, Mo, V, Zr, Hf and W, and satisfying, in atomic %, 81≦a≦86, 0.15≦b≦5.0, 12.5≦c≦15, 0≦d≦1.0, 0≦e≦1.0 and 0≦x≦0.1, a heating unit that heats the alloy ribbon while conveying the alloy ribbon in a state where a tension of 10 MPa to 160 MPa is applied to the alloy ribbon, and the alloy ribbon is brought into contact with a heating body so that the temperature rise rate of the alloy ribbon is 100 K / sec or more; When the crystallization temperature of the alloy ribbon is Tx1, the temperature Ta of the heater is in the range of Tx1+85°C to Tx1+140°C when e<0.4 in the composition formula, and in the range of Tx1+60°C to Tx1+100°C when e≧0.4 in the composition formula.

2. 2. The method for producing a nanocrystalline alloy ribbon according to claim 1, wherein the nanocrystalline alloy ribbon has a saturation magnetic flux density Bs of 1.6 T or more, a residual magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in a longitudinal direction of the nanocrystalline alloy ribbon is LBr, and a residual magnetic flux density Br (maximum measured magnetic field Hm=80 A / m) in a width direction perpendicular to the longitudinal direction is WBr, and LBr / WBr is 0.2 to 1.

8.

3. The nanocrystalline alloy ribbon according to claim 1 or 2, wherein the nanocrystalline alloy ribbon has a maximum magnetic permeability μm of 4000 or more, and the maximum magnetic permeability μm in the longitudinal direction of the nanocrystalline alloy ribbon (maximum measured magnetic field Hm=80 A / m) is L μm, and the maximum magnetic permeability μm in the width direction perpendicular to the longitudinal direction (maximum measured magnetic field Hm=80 A / m) is W μm, where L μm / W μm is 0.3 to 1.

7.

4. The method for producing a nanocrystalline alloy ribbon according to claim 1 or 2, wherein the anisotropic energy E (maximum measured magnetic field Hm = 800 A / m) of the nanocrystalline alloy ribbon is 400 J / m3 or less, and LE / WE is 0.2 to 1.8, where LE is the anisotropic energy E (maximum measured magnetic field Hm = 800 A / m) of the nanocrystalline alloy ribbon in the longitudinal direction and WE is the anisotropic energy E (maximum measured magnetic field Hm = 800 A / m) of the nanocrystalline alloy ribbon in the width direction perpendicular to the longitudinal direction.

5. The method for producing a nanocrystalline alloy ribbon according to claim 1 or 2, wherein the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto is 0.4 T or more, and when the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto in the longitudinal direction thereof is defined as LB80, and the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto in the width direction perpendicular to the longitudinal direction is defined as WB80, LB80 / WB80 is 0.3 to 1.

7.

6. The method for producing a nanocrystalline alloy ribbon according to claim 1 or 2, wherein the temperature of the alloy ribbon is controlled so as not to exceed Ta+50° C. during the heat treatment of the alloy ribbon.

7. The method for producing a nanocrystalline alloy ribbon according to claim 1 or claim 2, wherein the heating body is composed of a plurality of heating parts with different temperatures, and the temperature of the heating part with the highest temperature among the plurality of heating parts is the temperature Ta.

8. The nanocrystalline alloy ribbon has a structure in which crystal grains having an average grain size of 30 nm or less exist in an amorphous phase, The nanocrystalline alloy ribbon is represented by a composition formula (Fe1-xAx)aSibBcCudMe, A is at least one of Ni and Co, M is at least one selected from the group consisting of Nb, Mo, V, Zr, Hf, and W, and has atomic percentages of 81≦a≦86, 0.15≦b≦5.0, 12.5≦c≦15, 0≦d≦1.0, 0≦e≦1.0, and 0≦x≦0.1, and has a saturation magnetic flux density Bs of 1.6 T or more, The nanocrystalline alloy ribbon has a residual magnetic flux density Br (maximum measurable magnetic field Hm=80 A / m) in a longitudinal direction thereof as LBr and a residual magnetic flux density Br (maximum measurable magnetic field Hm=80 A / m) in a width direction perpendicular to the longitudinal direction as WBr, in which LBr / WBr is 0.2 to 1.

8.

9. The nanocrystalline alloy ribbon according to claim 8, wherein the nanocrystalline alloy ribbon has a maximum magnetic permeability μm of 4000 or more, a maximum magnetic permeability μm in the longitudinal direction of the nanocrystalline alloy ribbon (maximum measured magnetic field Hm=80 A / m) is L μm, and a maximum magnetic permeability μm in the width direction perpendicular to the longitudinal direction (maximum measured magnetic field Hm=80 A / m) is W μm, and L μm / W μm is 0.3 to 1.

7.

10. The nanocrystalline alloy ribbon according to claim 8 or 9, wherein the anisotropic energy E (maximum measured magnetic field Hm=800 A / m) of the nanocrystalline alloy ribbon is 400 J / m3 or less, and LE / WE is 0.2 to 1.8, where LE is the anisotropic energy E (maximum measured magnetic field Hm=800 A / m) of the nanocrystalline alloy ribbon in the longitudinal direction and WE is the anisotropic energy E (maximum measured magnetic field Hm=800 A / m) of the nanocrystalline alloy ribbon in the width direction perpendicular to the longitudinal direction.

11. The nanocrystalline alloy ribbon according to claim 8 or claim 9, wherein the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto is 0.4 T or more, and when the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto in the longitudinal direction thereof is defined as LB80, and the magnetic flux density B80 of the nanocrystalline alloy ribbon when a magnetic field of 80 A / m is applied thereto in the width direction perpendicular to the longitudinal direction is defined as WB80, the ratio LB80 / WB80 is 0.3 to 1.

7.

12. 10. The nanocrystalline alloy ribbon according to claim 8 or 9, which has a thickness of 15 μm or more and a width of 5 mm or more.

13. The nanocrystalline alloy ribbon according to claim 8 or 9, which has a space factor of 86% or more.

14. 10. The nanocrystalline alloy ribbon according to claim 8 or 9, wherein the saturation magnetostriction is 30 ppm or less.