Soft magnetic alloy ribbons and magnetic components

Abstract

To provide a soft magnetic alloy thin strip that is high in corrosion resistance and good in magnetic property.SOLUTION: Provided is a soft magnetic alloy thin strip that contains Fe and M. M is at least one selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Cr and Ti, and a part of M forms an oxide. When the concentration distribution of the elements contained in the soft magnetic alloy thin strip is measured from the surface of the soft magnetic alloy thin strip toward the inside in the thickness direction, the maximum point of the concentration of M forming at least one oxide is present in the region within 20 nm from the surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a soft magnetic alloy ribbon and a magnetic component. [Background technology]

[0002] Soft magnetic alloy materials are known as one type of soft magnetic material. Magnetic cores using soft magnetic alloy ribbons, which are soft magnetic alloy materials formed into a ribbon shape, are also known. To reduce the size and improve the performance of magnetic cores, it is necessary to improve the magnetic properties (saturation magnetic flux density) of the soft magnetic alloy ribbons.

[0003] Patent Document 1 describes an invention relating to an amorphous alloy ribbon and a nanocrystalline soft magnetic alloy, etc. According to Patent Document 1, by controlling the amount of C in the ribbon and further controlling the gas atmosphere near the cooling roll, it is possible to control the segregation of C that occurs on the ribbon surface.

[0004] Patent Document 2 describes an invention relating to an amorphous alloy ribbon and a nanocrystalline soft magnetic alloy, etc. According to Patent Document 2, by controlling the ribbon temperature on the roll during ribbon production, it is possible to control the segregation of Cu that occurs on the ribbon surface.

[0005] Patent Document 3 describes a soft magnetic alloy ribbon having a matrix in which fine crystal grains having an average grain size of 60 nm or less are dispersed in an amorphous matrix at a volume fraction of 50% or more, and having an oxide film on the surface, with a B concentration in part of the oxide film being lower than the average B concentration in the matrix. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-182594 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-263775 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-149045 Summary of the Invention [Problem to be solved by the invention]

[0007] Typically, soft magnetic alloy ribbons are manufactured by a rapid cooling method such as a single roll method. When soft magnetic alloy ribbons are mass-produced, they are generally manufactured in an air atmosphere. Therefore, Fe near the surface of the soft magnetic alloy ribbon is oxidized, resulting in a decrease in the total amount of magnetic material. Patent Documents 1 and 2 do not mention Fe oxidation. The soft magnetic alloy ribbon of Patent Document 3 has a thick oxide film, resulting in a decrease in the total amount of magnetic material.

[0008] An object of the present invention is to obtain a soft magnetic alloy ribbon having high corrosion resistance and good magnetic properties. [Means for solving the problem]

[0009] In order to achieve the above object, a soft magnetic alloy ribbon of the present invention is a soft magnetic alloy ribbon containing Fe and M, M is at least one selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Ti and Cr, and a part of M forms an oxide; When the concentration distribution of elements contained in the soft magnetic alloy ribbon is measured from the surface of the soft magnetic alloy ribbon toward the inside in the thickness direction, a maximum point of the concentration of at least one kind of M forming an oxide is present in a region within 20 nm from the surface.

[0010] The soft magnetic alloy ribbon of the present invention has the above-mentioned characteristics, and is therefore a soft magnetic alloy ribbon with high corrosion resistance and excellent magnetic properties.

[0011] The soft magnetic alloy ribbon of the present invention may further contain Si, A part of Si may form an oxide, When a concentration distribution of elements contained in the soft magnetic alloy ribbon is measured from a surface of the soft magnetic alloy ribbon toward the inside in a thickness direction, a maximum point of the concentration of Si forming an oxide may be present in a region within 20 nm from the surface.

[0012] The concentration of M forming an oxide at a maximum point of the concentration of the at least one M forming an oxide is defined as [M], and the concentration of Si forming an oxide at a maximum point of the concentration of Si forming an oxide is defined as [Si], [Si] / [M]≧1.50 may be satisfied.

[0013] In the soft magnetic alloy ribbon of the present invention, the composition ratio of Si may be 0.1 at % or more and 10 at % or less.

[0014] In the soft magnetic alloy ribbon of the present invention, the composition ratio of M may be more than 3 at % and 10 at % or less.

[0015] The soft magnetic alloy ribbon of the present invention may be amorphous.

[0016] The soft magnetic alloy ribbon of the present invention may contain nanocrystals.

[0017] The magnetic component of the present invention is made of the above-described soft magnetic alloy ribbon. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a graph showing the relationship between the depth from the surface and the composition of sample No. 6. [Figure 2] FIG. 2 is an example of a chart obtained by X-ray crystal structure analysis. [Figure 3] FIG. 3 shows an example of a pattern obtained by profile fitting the chart of FIG. [Figure 4] FIG. 4 is a schematic diagram of a single-roll quenching ribbon apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0020] There is no particular limitation on the dimensions of the soft magnetic alloy ribbon of this embodiment, and it may have a thickness of 5 to 30 μm and a width of 5 to 250 mm, for example.

[0021] The soft magnetic alloy ribbon of this embodiment contains Fe and M. M is at least one selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Ti, and Cr, and a part of M forms an oxide.

[0022] When the concentration distribution of elements contained in the soft magnetic alloy ribbon is measured from the surface of the soft magnetic alloy ribbon toward the inside in the thickness direction, the maximum concentration point of M forming the oxide exists in a region within 20 nm from the surface.

[0023] The maximum concentration of M forming the oxide exists in a region within 20 nm from the surface, and thus an oxide layer of the M element segregates on the surface. As a result, oxidation of Fe can be suppressed, and the corrosion resistance of the soft magnetic alloy ribbon is improved. Furthermore, the magnetic properties are also improved.

[0024] The soft magnetic alloy ribbon of the present embodiment may further contain Si. When a concentration distribution of elements contained in the soft magnetic alloy ribbon is measured from a surface of the soft magnetic alloy ribbon toward the inside in the thickness direction, a maximum point of the concentration of Si forming an oxide may be present in a region within 20 nm from the surface.

[0025] FIG. 1 shows the results of measuring the concentration distribution of elements contained in the soft magnetic alloy ribbon according to this embodiment from the surface toward the inside in the thickness direction using X-ray photoelectron spectroscopy (XPS). XPS can distinguish between elemental substances and oxides, so it is possible to measure the concentration distribution of each element forming the oxide. Furthermore, although the soft magnetic alloy ribbon according to this embodiment has an uneven surface, XPS can be used to measure the concentration distribution of each element according to the SiO2-equivalent depth from the surface. Another method for measuring the concentration distribution of each element is to use a transmission electron microscope instead of XPS. The concentration distribution of each element can be measured using a transmission electron microscope and energy dispersive X-ray spectroscopy (EDS), electron energy loss spectroscopy (EELS), or the like. Like XPS, EELS can measure the valence of elements, so it is possible to distinguish between elemental substances and oxides.

[0026] As can be seen from Figure 1, the maximum concentration points of Nb-O (Nb forming oxide) and Si-O (Si forming oxide) are located within a region 20 nm from the surface (SiO2 equivalent depth 0 nm).

[0027] The concentration distribution is measured within a region of 50 nm from the surface, with the distance between measurement points being 1.0 nm or more and 4.0 nm or less in terms of SiO2.

[0028] The method for identifying the concentration maximum point in this embodiment will be described below. First, the concentration of each measurement point within the measurement range of the concentration distribution is confirmed. A measurement point with a higher concentration than any of its adjacent measurement points is the maximum point. Furthermore, if the concentrations of two or more adjacent measurement points are the same, the two or more measurement points are considered to be a single measurement point group. Then, if the concentration of the measurement point group is higher than the concentration of any of its adjacent measurement points, the measurement point of the measurement point group that is closest to the surface is the maximum point.

[0029] Furthermore, the concentration of M forming the oxide at the maximum concentration point of M forming the oxide may be [M], and the concentration of Si forming the oxide at the maximum concentration point of Si forming the oxide may be [Si], so that [Si] / [M]≧1.5 may be satisfied. By satisfying [Si] / [M]≧1.5, M and Si form a layer on the surface, thereby improving the corrosion resistance of the soft magnetic alloy ribbon. Furthermore, magnetic properties are also improved. Note that, when there are multiple maximum points, the concentration of the maximum point closest to the surface among the multiple maximum points is designated as [M] or [Si]. Note that there is no particular upper limit for [Si] / [M], but for example, [Si] / [M]≦20 may be satisfied.

[0030] The concentration of each element inside the soft magnetic alloy ribbon is specifically an average value of the concentration of each element in a portion 1.0 to 1.3 μm from the surface of the soft magnetic alloy ribbon. Usually, the concentration of each element inside the soft magnetic alloy ribbon and the composition ratio of each element in the entire soft magnetic alloy ribbon are approximately the same.

[0031] The Si composition ratio in the soft magnetic alloy ribbon according to this embodiment is not particularly limited, and may be 0 at% or more and 18 at% or less, 0 at% or more and 13.5 at% or less, or 0.1 at% or more and 10 at% or less. When the Si composition ratio is 0.1 at% or more, corrosion resistance is likely to be improved. Furthermore, when the Si composition ratio is 0.1 at% or more and 10 at% or less, saturation magnetic flux density is likely to be improved.

[0032] The composition ratio of M in the soft magnetic alloy ribbon according to this embodiment is not particularly limited, but may be 0.1 at% or more and 15 at% or less, 3 at% or more and 12 at% or less, or more than 3 at% and 10 at% or less. In particular, when the composition ratio of M is more than 3 at% and 10 at% or less, corrosion resistance is likely to be improved.

[0033] In order to achieve both saturation magnetic flux density and corrosion resistance, the composition ratio of M may be 2 at % or more and 10 at % or less.

[0034] The microstructure of the soft magnetic alloy ribbon according to this embodiment is not particularly limited. For example, the soft magnetic alloy ribbon according to this embodiment may have a structure consisting of only amorphous, or may have a nanoheterostructure in which primary microcrystals exist in the amorphous. The primary microcrystals may have an average grain size of 0.3 to 10 nm. In this embodiment, when the amorphization rate described later is 85% or more, the soft magnetic alloy ribbon is considered to have a structure consisting of only amorphous or a nanoheterostructure.

[0035] The soft magnetic alloy ribbon according to the present embodiment may have a structure made of nanocrystals, and among the structures made of nanocrystals, may particularly have a structure made of Fe-based nanocrystals.

[0036] Nanocrystals refer to crystals with a particle size on the nanometer order. Fe-based nanocrystals refer to crystals with a particle size on the nanometer order and an Fe crystal structure of bcc (body-centered cubic lattice structure). In this embodiment, it is preferable to precipitate Fe-based nanocrystals with an average particle size of 5 to 30 nm. The soft magnetic alloy ribbon 24 in which such Fe-based nanocrystals are precipitated tends to have a high saturation magnetic flux density and a low coercive force. In this embodiment, in the case of a structure including nanocrystals and a structure including Fe-based nanocrystals, the amorphization rate described below is less than 85%.

[0037] Hereinafter, a method for confirming whether a soft magnetic alloy ribbon has an amorphous structure (a structure consisting only of amorphous or a nanoheterostructure) or a crystalline structure will be described. In this embodiment, a soft magnetic alloy ribbon having an amorphous ratio X shown in the following formula (1) of 85% or more has an amorphous structure, and a soft magnetic alloy ribbon having an amorphous ratio X of less than 85% has a crystalline structure. X = 100 - (Ic / (Ic + Ia) × 100) ... (1) Ic: Crystalline scattering integrated intensity Ia: Amorphous scattering integrated intensity

[0038] The amorphous ratio X is calculated by performing a crystal structure analysis on the soft magnetic alloy ribbon by X-ray diffraction (XRD), identifying the phase, reading the peaks of crystallized Fe or a compound (Ic: crystalline scattering integrated intensity, Ia: amorphous scattering integrated intensity), determining the crystallization ratio from the peak intensity, and then calculating the crystallization ratio X using the above formula (1). The calculation method will be described in more detail below.

[0039] The soft magnetic alloy ribbon according to this embodiment is subjected to crystal structure analysis by XRD to obtain a chart as shown in Fig. 2. This is subjected to profile fitting using the Lorentz function of the following formula (2), and a crystalline component pattern α indicating the crystalline scattering integrated intensity as shown in Fig. 3 is obtained. c , amorphous component pattern α showing amorphous scattering integrated intensity a , and the combined pattern α c+a The amorphization rate X is calculated from the crystalline scattering integrated intensity and amorphous scattering integrated intensity of the obtained pattern using the above formula (1). The measurement range is set to a diffraction angle 2θ of 30° to 60°, where a halo derived from amorphous matter can be confirmed. Within this range, the error between the integrated intensity actually measured by XRD and the integrated intensity calculated using the Lorentz function is set to within 1%.

[0040]

number

[0041] The soft magnetic alloy ribbon of this embodiment has the composition formula (Fe (1-(α+β)) X1 α X2 β ) (1-(a+b+c+d)) M a B b P c Si d It may have a main component consisting of 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, Bi, S, N, O and rare earth elements; M is one or more selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Cr and Ti; 0.001≦a≦0.150 0.020≦b≦0.200 0≦c≦0.150 0≦d≦0.180 α≧0 β≧0 0≦α+β≦0.50 may be.

[0042] The soft magnetic alloy ribbon having the above composition is likely to form an amorphous phase. Furthermore, when the soft magnetic alloy ribbon having the above composition is heat-treated, Fe-based nanocrystals are likely to precipitate in the soft magnetic alloy ribbon.

[0043] Hereinafter, each component of the soft magnetic alloy ribbon 24 according to this embodiment other than M and Si will be described in detail.

[0044] The B content (b) may satisfy the condition 0.020≦b≦0.200, or 0.030≦b≦0.120.

[0045] The P content (c) may satisfy the relationship 0≦c≦0.150, or 0.010≦c≦0.050.

[0046] The Fe content (1-(a+b+c+d)) is not particularly limited, but may be 0.70≦(1-(a+b+c+d))≦0.900.

[0047] In the soft magnetic alloy ribbon of this embodiment, a portion of Fe may be substituted with X1 and / or X2.

[0048] X1 is one or more elements selected from the group consisting of Co and Ni. Regarding the content of X1, α may be 0. That is, X1 may not be contained. Furthermore, the number of atoms of X1 is preferably 40 at% or less, where 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)}≦0.400.

[0049] X2 is one or more elements selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Bi, S, N, O, and rare earth elements. β=0 may be satisfied for the content of X2. That is, X2 may not be contained. Furthermore, the number of atoms of X2 is preferably 3.0 at% or less, where the number of atoms in the entire composition is 100 at%. That is, it is preferable to satisfy the following relationship: 0≦β{1-(a+b+c+d)}≦0.030. Note that oxygen contained near the surface and forming oxides with M and Si is also included in X2, but this amount is so small as to be negligible when viewed from the perspective of the entire soft magnetic alloy ribbon.

[0050] The range of the amount of Fe substituted with X1 and / or X2 may be half or less of that of Fe on an atomic number basis, that is, 0≦α+β≦0.50.

[0051] The soft magnetic alloy ribbon of the present embodiment may contain elements other than those mentioned above as unavoidable impurities, for example, 0.1% by weight or less relative to 100% by weight of the soft magnetic alloy ribbon.

[0052] The compositions that make it easy to obtain a soft magnetic alloy ribbon having Fe-based nanocrystals have been described above, but there is no particular limitation on the microstructure of the soft magnetic alloy ribbon, and there is no particular limitation on the composition of the soft magnetic alloy ribbon other than that it contains M. It is sufficient that the soft magnetic alloy ribbon has a composition that contains M.

[0053] (Method of manufacturing soft magnetic alloy ribbon) The method for producing the soft magnetic alloy ribbon of this embodiment will be described below.

[0054] There is no particular limitation on the method for producing the soft magnetic alloy ribbon of this embodiment. For example, a single roll method may be used to produce the soft magnetic alloy ribbon. The ribbon may also be a continuous ribbon.

[0055] In the single-roll method, first, pure raw materials of each element to be contained in the soft magnetic alloy ribbon finally obtained are prepared and weighed so as to have the same composition as the soft magnetic alloy ribbon finally obtained. Then, the pure raw materials of each element are melted and mixed to prepare a master alloy. Note that any method for melting the pure raw materials may be used, but for example, a method in which the raw materials are melted by high-frequency heating after evacuating a chamber may be used. Note that the master alloy and the soft magnetic alloy ribbon finally obtained usually have the same composition.

[0056] Next, the produced master alloy is heated and melted to obtain a molten metal (molten metal). There are no particular restrictions on the temperature of the molten metal, but it can be set to 1200 to 1500°C, for example.

[0057] A schematic diagram of a single-roll quenching ribbon apparatus used in the single-roll method according to this embodiment is shown in Fig. 4. Inside a chamber 25, molten metal 22 is quenched by being sprayed as a continuous liquid from a nozzle 21 through a slit at the bottom of the nozzle 21 and supplied to a roll 23 rotating in the direction of the arrow, thereby producing a uniform ribbon 24 in the rotation direction of the roll 23. In this embodiment, the material of the roll 23 is, for example, Cu. There are no particular restrictions on the atmosphere inside the chamber 25, but an air atmosphere is particularly suitable for mass production.

[0058] 4, the single-roll quenching ribbon apparatus has a stripping gas injection device 26 and a blowing gas injection device 27. By controlling the oxygen concentrations of the gases injected from the stripping gas injection device 26 and the blowing gas injection device 27, it is possible to control the concentration distribution of oxides of each element near the surfaces of both sides of the ribbon.

[0059] There are no particular restrictions on the oxygen concentration in the stripping gas and the spray gas, but it may be 0.5 to 100%, 5 to 100%, or 30 to 100%. There are also no particular restrictions on the injection pressure of the stripping gas and the spray gas, for example, 10 kPa or more and 300 kPa or less. The stripping gas and the spray gas may have the same oxygen concentration and / or injection pressure, or they may have different oxygen concentrations and / or injection pressures.

[0060] The soft magnetic alloy ribbon 24 obtained by the above method may not contain crystals having a grain size of more than 30 nm. The soft magnetic alloy ribbon 24 may have a structure consisting of only amorphous material, or may have a nanoheterostructure in which crystals having a grain size of 30 nm or less exist in the amorphous material.

[0061] There is no particular limitation on the method for confirming whether or not the soft magnetic alloy ribbon 24 contains crystals with a grain size greater than 30 nm. For example, the presence or absence of crystals with a grain size greater than 30 nm can be confirmed by ordinary X-ray diffraction measurement. Alternatively, direct observation may be performed using a transmission electron microscope.

[0062] There are no particular limitations on the method for observing the presence or absence of the primary microcrystals and the average particle size. For example, the presence or absence of the primary microcrystals and the average particle size can be confirmed by obtaining a selected area diffraction image, a nanobeam diffraction image, a bright-field image, or a high-resolution image using a transmission electron microscope on a sample sliced ​​by ion milling. When using a selected area diffraction image or a nanobeam diffraction image, ring-shaped diffraction is formed in the diffraction pattern in the case of an amorphous material, whereas diffraction spots due to the crystalline structure are formed in the case of a non-amorphous material. When using a bright-field image or a high-resolution image, a magnification of 1.00 × 10 5 ~3.00×10 5 The presence or absence of primary microcrystals and their average particle size can be observed by visual observation at a magnification of 100x.

[0063] By controlling the oxygen concentrations of the gases injected from the stripping gas injection device 26 and the blowing gas injection device 27, the soft magnetic alloy ribbon 24 having a concentration distribution of the oxide of M according to this embodiment can be obtained.

[0064] The heat treatment conditions for producing the soft magnetic alloy ribbon of this embodiment are not particularly limited as long as oxidation of the surface of the soft magnetic alloy ribbon does not progress. The preferred heat treatment conditions vary depending on the composition of the soft magnetic alloy ribbon. Generally, the preferred heat treatment temperature is approximately 400 to 700°C, and the preferred heat treatment time is approximately 0.5 to 10 hours. However, depending on the composition, the preferred heat treatment temperature and heat treatment time may be outside the above ranges. Furthermore, the heat treatment is performed in an inert atmosphere such as Ar gas or in a vacuum atmosphere to maintain the surface condition of the soft magnetic alloy ribbon.

[0065] By performing heat treatment in an inert atmosphere or a vacuum atmosphere, the diffusion of elements constituting the soft magnetic alloy ribbon 24 can be promoted while maintaining the surface state, allowing the thermodynamic equilibrium state to be reached in a short time, and strain and stress present in the soft magnetic alloy ribbon can be removed. As a result, a soft magnetic alloy with improved saturation magnetic flux density can be easily obtained. Furthermore, when heat treatment is performed at a temperature above the temperature at which Fe-based nanocrystals precipitate, Fe-based nanocrystals precipitate. Therefore, by performing heat treatment in an inert atmosphere at a temperature above the temperature at which Fe-based nanocrystals precipitate, a soft magnetic alloy ribbon with further improved saturation magnetic flux density can be easily obtained.

[0066] There is no particular limitation on the method for calculating the average particle size of the Fe-based nanocrystals contained in the soft magnetic alloy ribbon obtained by heat treatment. For example, it can be calculated by observation using a transmission electron microscope. There is also no particular limitation on the method for confirming that the crystal structure is a bcc (body-centered cubic lattice structure). For example, it can be confirmed using X-ray diffraction measurement.

[0067] Hereinafter, a method for obtaining the core and inductor according to this embodiment will be described, but the method for obtaining the core and inductor from the soft magnetic alloy ribbon is not limited to the method described below.

[0068] Examples of methods for obtaining a core from a soft magnetic alloy ribbon include a method of winding or laminating the soft magnetic alloy ribbon. When laminating soft magnetic alloy ribbons with an insulator interposed therebetween, a core with further improved properties can be obtained.

[0069] Furthermore, an inductor can be obtained by winding a wire around the core. There are no particular limitations on the method of winding the wire or the method of manufacturing the inductor. For example, there is a method in which a wire is wound at least one turn around the core manufactured by the above method.

[0070] The magnetic components according to the present embodiment, particularly the cores and inductors (coils) using the cores, can be obtained from the soft magnetic alloy ribbon according to the present embodiment. The cores can also be used in applications other than inductors, such as transformers. Transformers and inductors are used in power devices and the like.

[0071] The core according to this embodiment is particularly suitable for use in small power devices. Transformers and inductors typically occupy a large volume within a power device. However, the core according to this embodiment can maintain a sufficiently high saturation magnetic flux density even when miniaturized. Therefore, transformers and inductors using the core according to this embodiment can easily maintain a sufficiently high maximum magnetic flux density when the power device is operating, even when their volumes are reduced. For these reasons, the core according to this embodiment is particularly suitable for use in small power devices.

[0072] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

[0073] The soft magnetic alloy ribbon according to this embodiment can control the oxidation state of the soft magnetic alloy ribbon surface by using a stripping gas and a spray gas even when produced in an air atmosphere. Therefore, the oxidation of Fe on the soft magnetic alloy ribbon surface can be uniformly controlled, and the corrosion resistance of the soft magnetic alloy ribbon can be controlled. Furthermore, when Fe is locally oxidized on the soft magnetic alloy ribbon surface, the oxidation of Fe tends to progress in the air, and the Fe oxide phase tends to grow. This tends to reduce the total amount of magnetic material in the soft magnetic alloy ribbon. Therefore, as described above, the soft magnetic alloy ribbon according to this embodiment is particularly suitable for use in magnetic components that require an improvement in saturation magnetic flux density. Therefore, the magnetic components according to this embodiment are particularly suitable for miniaturizing power supply circuits, etc., of electronic devices, information devices, communication devices, etc. [Example]

[0074] The present invention will be specifically described below based on examples.

[0075] (Experimental Example 1) The raw materials were weighed so as to have the alloy composition shown in Table 1, and were melted by high-frequency heating to prepare master alloys.

[0076] The mother alloy was then heated to melt it to form a molten metal at 1300°C, and the metal was then sprayed onto a roll by a single roll method in which the roll was rotated at a rotation speed of 30 m / sec., to produce a thin ribbon. The roll material was Cu.

[0077] The roll was rotated in the direction shown in FIG. 4, and the roll temperature was set to 30°C. The differential pressure (injection pressure) between the chamber and the injection nozzle was set to 60 kPa. The slit width of the slit nozzle was set to 50 mm, the distance from the slit opening to the roll was set to 0.2 mm, and the roll diameter was set to φ300 mm, resulting in a ribbon having a thickness of 20 to 30 μm and a width of 50 mm.

[0078] Furthermore, the oxygen concentrations of the stripping gas and spray gas when using the single roll method are shown in Tables 1 and 2. Note that for samples with an oxygen concentration of 0% in the stripping gas and spray gas, N2 gas was sprayed, and for samples with an oxygen concentration other than 0% in the stripping gas and spray gas, N2-O2 mixed gas was sprayed.

[0079] Furthermore, we confirmed whether the ribbons before the heat treatment were amorphous or crystalline. The amorphization rate X of each ribbon was measured using XRD, and when X was 85% or more, the ribbon was deemed to be amorphous.

[0080] Thereafter, the ribbons of each of the examples and comparative examples in Table 1 were heat-treated at 600°C for 60 minutes in an N2 atmosphere (oxygen concentration 10 ppm or less). The crystal grain size of each heat-treated ribbon was measured using a transmission electron microscope. It was confirmed that the ribbons contained nanocrystals with crystal grain sizes of 5 nm to 30 nm. The results are shown in Table 2.

[0081] Furthermore, for sample number 6 in Table 1, a ribbon before heat treatment was produced under the same conditions as those in Example 1, except that the type of M was changed, and heat treatment was carried out under the same conditions. The results are shown in Table 3.

[0082] For each ribbon in Tables 1 to 3, the concentration distribution of elements contained in the soft magnetic alloy ribbon was measured using XPS from the surface (thickness 0 nm) toward the inside in the thickness direction. The concentration distribution measurement was performed so that the distance between measurement points in a region within 16 nm from the surface was 1.6 nm in SiO2 equivalent, and the distance between measurement points in a region 16 nm deep or more was 3.2 nm in SiO2 equivalent. Tables 1 to 3 show the presence or absence of maximum points and maximum values ​​for the M element forming an oxide and the Si element forming an oxide. Note that if a maximum point is present, it is recorded as "present," and if no maximum point is present, it is recorded as "absent."

[0083] The saturation magnetic flux density of each heat-treated ribbon was measured using a vibrating sample magnetometer (VSM) in a magnetic field of 1500 kA / m.

[0084] The obtained ribbons were subjected to a corrosion resistance test to confirm their corrosion resistance. Specifically, each sample was placed in a thermostatic chamber maintained at a temperature of 85°C and a humidity of 85%, and the surface of each sample was visually inspected every 30 minutes to confirm the presence or absence of rust spots. The time until the first rust spots were observed was rated A when it was 2.0 times or more compared to each comparative example (when N2 gas was sprayed), B when it was 1.2 times or more but less than 2.0 times, C when it was more than 1.0 times but less than 1.2 times, and D when it was 1.0 times or less, as shown in Tables 1 to 3. A rating of C or higher was considered good. Sample No. 1 is used as the standard in Table 1, and sample No. 9 is used in Tables 2 and 3.

[0085] The microstructure of the soft magnetic alloy ribbons of each example and comparative example was confirmed by X-ray diffraction measurement and observation using a transmission electron microscope. The results are shown in Tables 1 to 3. In addition, it was confirmed by ICP analysis that there was no change in the alloy composition before and after the heat treatment.

[0086] [Table 1]

[0087] [Table 2]

[0088] As can be seen from Tables 1 and 2, when the maximum concentration of M (Nb) forming the oxide was present within 20 nm from the surface, the corrosion resistance was superior to that when the maximum concentration of M forming the oxide was not present. Furthermore, when the maximum concentration of M (Nb) forming the oxide was present within 20 nm from the surface after heat treatment, the saturation magnetic flux density was also better than that of the same composition except that the maximum concentration of M forming the oxide was not present.

[0089] In particular, when [Si] / [M]≧1.50 was satisfied, the corrosion resistance was particularly good.

[0090] [Table 3]

[0091] From Table 3, it can be seen that the same results were obtained even when the type of M element was changed from Nb.

[0092] (Experimental Example 2) Experiments similar to those in each of the experimental examples in Table 2 were conducted by changing the composition from that of experimental example 1. The results are shown in Tables 4 to 6. The corrosion resistance test was conducted using sample number 22 in Table 4, sample number 32 in Table 5, and sample number 40 in Table 6 as the reference. The microstructure of the soft magnetic alloy ribbons in each of the examples and comparative examples was nanocrystalline.

[0093] [Table 4]

[0094] [Table 5]

[0095] [Table 6]

[0096] From Tables 4 to 6, when the maximum point of the concentration of M(Nb) forming an oxide exists in the region within 20 nm from the surface even if the composition is changed, the corrosion resistance was excellent compared to the case where it did not exist. Further, when comparing Sample No. 22 and Sample No. 23 having the same composition with each other, Sample No. 23 in which the maximum point of the concentration of M forming an oxide exists had an excellent saturation magnetic flux density compared to Sample No. 22 in which the maximum point of the concentration of M forming an oxide did not exist. When comparing Sample No. 32 and Sample No. 33 having the same composition with each other, Sample No. 33 in which the maximum point of the concentration of M forming an oxide exists had an excellent saturation magnetic flux density compared to Sample No. 32 in which the maximum point of the concentration of M forming an oxide did not exist. When comparing Sample No. 40 and Sample No. 41 having the same composition with each other, Sample No. 41 in which the maximum point of the concentration of M forming an oxide exists had an excellent saturation magnetic flux density compared to Sample No. 40 in which the maximum point of the concentration of M forming an oxide did not exist.

[0097] From Table 4, the saturation magnetic flux density increased when the composition ratio of Si was 0.1 at% or more and 10 at% or less, that is, 0.001 ≦ d ≦ 0.100. From Table 5, the corrosion resistance increased when the composition ratio of M exceeded 3 at% and was 10 at% or less, that is, 0.030 < a ≦ 0.100. From Table 6, the corrosion resistance was good when the content of P satisfied 0.1 at% or more and 15 at% or less, that is, 0 ≦ c ≦ 0.150.

[0098] (Experimental Example 3) After changing the composition of the soft magnetic alloy ribbon to a commonly used composition, experiments similar to those of the experimental examples in Table 2 were conducted. The results are shown in Table 7. In the corrosion resistance test, sample number 47 was based on sample number 46, sample number 49 was based on sample number 48, sample number 51 was based on sample number 50, and sample number 53 was based on sample number 52. Table 7 also shows the microstructures of the soft magnetic alloy ribbons of the examples and comparative examples.

[0099] [Table 7]

[0100] As can be seen from Table 7, even when the composition was changed, when the maximum concentration of M (Nb) forming the oxide was present in a region within 20 nm from the surface, the corrosion resistance and saturation magnetic flux density were superior compared to when the maximum concentration of M forming the oxide was not present. [Explanation of symbols]

[0101] 21... Nozzle 22... Molten metal 23... Roll 24… Soft magnetic alloy ribbon 25... Chamber 26... Stripping gas injection device 27... Spray gas injection device

Claims

1. A soft magnetic alloy ribbon containing Fe and M, The soft magnetic alloy ribbon has a composition formula (Fe (1-( α + β )) X1αX2β) (1-(a+b+c+d)) M a B b P c Si d It consists of 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, Bi, S, N, O and rare earth elements; M is at least one selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Cr, and Ti, and a part of M forms an oxide; 0.001≦a≦0.150 0.020≦b≦0.200 0≦c≦0.150 0≦d≦0.180 0.70≦(1-(a+b+c+d))≦0.900 0≦α{1-(a+b+c+d)}≦0.400 0≦β{1-(a+b+c+d)}≦0.030 ０≦α＋β≦０．５０ and The soft magnetic alloy ribbon may contain elements other than those described above as unavoidable impurities in an amount of 0.1% by weight or less relative to 100% by weight of the soft magnetic alloy ribbon, When a concentration distribution of elements contained in the soft magnetic alloy ribbon is measured from a surface of the soft magnetic alloy ribbon toward the inside in a thickness direction, a maximum point of the concentration of at least one kind of M forming an oxide is present in a region within 20 nm from the surface, The soft magnetic alloy ribbon has a concentration of M forming an oxide at a maximum concentration point of the at least one M forming an oxide, and [M] is 0.6 at% or more.

2. A soft magnetic alloy ribbon further containing Si, A part of Si forms an oxide, 2. The soft magnetic alloy ribbon according to claim 1, wherein, when a concentration distribution of elements contained in the soft magnetic alloy ribbon is measured from a surface of the soft magnetic alloy ribbon toward the inside in a thickness direction, a maximum point of a concentration of Si forming an oxide is present in a region within 20 nm from the surface.

3. The concentration of Si forming the oxide at the maximum point of the concentration of Si forming the oxide is defined as [Si], The soft magnetic alloy ribbon according to claim 2, wherein [Si] / [M]≧1.50 is satisfied.

4. 4. The soft magnetic alloy ribbon according to claim 1, wherein the composition ratio of Si is 0.1 at % or more and 10 at % or less.

5. 5. The soft magnetic alloy ribbon according to claim 1, wherein the composition ratio of M is more than 3 at % and 10 at % or less.

6. The soft magnetic alloy ribbon according to any one of claims 1 to 5, which is amorphous.

7. The soft magnetic alloy ribbon according to any one of claims 1 to 5, which contains nanocrystals.

8. A magnetic part made of the soft magnetic alloy ribbon according to any one of claims 1 to 7.

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