JP2018073945A - Composite magnetic particle and magnetic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide composite magnetic particles which enable the arrangement of a mold increased in the volume percentage of a soft magnetic material, which can reduce the iron loss Pcv of a mold thereof, and which can increase an initial magnetic permeability μand a saturated magnetic flux density Bs; and a magnetic component.SOLUTION: A composite magnetic particle 1 comprises: soft magnetic alloy powder 11 including at least one of amorphous metal alloy powder and nanocrystal alloy powder; and a columnar crystal layer 12 having a thickness of 1 μm or less on at least a part of the surface of the soft magnetic alloy powder 11.SELECTED DRAWING: Figure 1

Description

  The present invention relates to composite magnetic particles and a magnetic component using a molded body containing the composite magnetic particles.

Soft magnetic alloy powders such as amorphous alloy powders and nanocrystalline alloy powders used in conventional magnetic parts are soft magnetic alloy powders in order to prevent an increase in iron loss due to eddy currents generated when high frequency excitation is performed. An attempt is made to reduce the iron loss by forming an insulating layer with a silicon oxide film (SiO ₂ ), magnesium oxide (MgO), alumina (Al ₂ O ₃ ), or the like on the surface.

For example, a pulverized powder obtained by pulverizing an Fe-based amorphous alloy ribbon having a crystallization temperature Tx of 420 ° C. to 600 ° C. and an Fe-based amorphous alloy atomized spherical powder are mixed, molded, and heat-treated to form a dust core (core ), A particle structure is proposed in which the pulverized powder is a thin plate having an average thickness of 20 μm to 60 μm and an average particle diameter of 60 μm to 80 μm and an SiO ₂ film is formed thereon (see Patent Document 1).

However, since the insulating layer such as SiO ₂ , MgO, Al ₂ O ₃ formed on the surface of the conventional soft magnetic alloy powder described in Patent Document 1 does not exhibit magnetism, the compact is formed by forming a compact. In the case of the powder magnetic core (core), there is a problem that the volume ratio of the soft magnetic material is low and the saturation magnetic flux density Bs and the initial permeability μ _{i of} the powder magnetic core are low.

Japanese Patent Laid-Open No. 2016-27656

The present invention makes it possible to form a molded body in which the volume ratio of the soft magnetic material is increased, reduce the iron loss Pcv of the molded body, and increase the initial magnetic permeability μ _i and the saturation magnetic flux density Bs. It aims at providing the magnetic component using the molded object containing a grain and this composite magnetic grain.

  In order to achieve the above object, the first aspect of the present invention includes (a) a soft magnetic alloy powder containing at least one of an amorphous alloy powder and a nanocrystalline alloy powder, and (b) a surface of the soft magnetic alloy powder. The gist of the present invention is a composite magnetic grain provided with a columnar crystal layer having a thickness of 1 μm or less provided at least in part.

  The gist of the second aspect of the present invention is a magnetic component using a molded body containing the composite magnetic particles described in the first aspect.

According to the present invention, it is possible to configure a molded body in which the volume ratio of the soft magnetic material is increased, the iron loss Pcv of the molded body can be reduced, and the initial permeability μ _i and the saturation magnetic flux density Bs can be increased. It is possible to provide a magnetic component using composite magnetic particles and a molded body containing the composite magnetic particles.

It is typical sectional drawing explaining the outline of the structure of the composite magnetic grain which concerns on one Embodiment of this invention. It is a transmission electron microscope (TEM) photograph explaining the outline of the structure of the composite magnetic grain which concerns on one Embodiment of this invention. It is an element mapping figure explaining distribution of oxygen concentration of the composite magnetic grain concerning one embodiment of the present invention. It is an element mapping figure explaining distribution of the iron concentration of the composite magnetic grain concerning one embodiment of the present invention. It is a figure which shows the X-ray-diffraction profile of the non-heat processing state of the soft magnetic alloy powder which concerns on one Embodiment of this invention. It is a TEM photograph of the non-heat-treated state of the soft magnetic alloy powder which concerns on one Embodiment of this invention. It is a table | surface explaining the heat processing conditions of Examples 1-6. It is a TEM photograph after heat processing of the soft magnetic alloy powder which concerns on one Embodiment of this invention. It is a table | surface explaining the saturation magnetic flux density Bs after shaping | molding of Examples 1-6, initial permeability (micro | micron | mu) _i , and the iron loss Pcv of a powder magnetic core. It is a table | surface explaining the composition etc. of the soft magnetic alloy powder used for Comparative Examples 1-3. It is a table | surface explaining the saturation magnetic flux density Bs after shaping | molding of Comparative Examples 1-3, initial permeability (micro | micron | mu) _i , and the iron loss Pcv of a powder magnetic core. Insulating the thickness of each columnar crystal layer, the minor axis dimension of the columnar crystal layer, the oxygen concentration of the columnar crystal layer, the oxygen concentration of the metal structure of the soft magnetic alloy powder, etc. in Examples 7 to 9 and Comparative Examples 4 to 15 it is a table showing with the thickness of the layer (SiO ₂ layer). It is a table | surface explaining the saturation magnetic flux density Bs after shaping | molding of Examples 7-9 and Comparative Examples 4-15, initial permeability (micro | micron | mu) _i , and the iron loss Pcv of a powder magnetic core. It is a figure which shows the relationship between the saturation magnetic flux density Bs of Examples 7-9 and Comparative Examples 4-15, and the thickness of a columnar crystal layer. It is a figure which shows the relationship between the initial permeability (micro | micron | mu) _{i of} Examples 7-9 and Comparative Examples 4-15, and the thickness of a columnar crystal layer. The relationship between the iron loss Pcv of the dust cores according to Examples 7 to 9 and Comparative Examples 4 to 15 and the thickness of the columnar crystal layer is enlarged in the vicinity of 5000 kW / m ³ (4500 kW / m ^{3 to} 5500 kW / m ³ ). FIG. It is a figure which shows the relationship between the iron loss Pcv of the powder magnetic core which concerns on Examples 7-9 and Comparative Examples 4-15, and the thickness of a columnar crystal layer. It is the table | surface which displayed the relationship between the thickness of the insulating layer provided in the surface of soft-magnetic alloy powder, and the thickness of a columnar crystal layer about the sample of Examples 7-9 and Comparative Examples 4-15 in matrix form. It is the table | surface which displayed the value of each saturation magnetic flux density Bs by the matrix display corresponding to the matrix display of FIG. 18 about the sample of Examples 7-9 and Comparative Examples 4-15. As a table corresponding to the matrix in which the samples of Example 7, Comparative Example 7, and Comparative Example 12 in which the thickness of the columnar crystal layer is 200 nm are deleted from the matrix display sample of FIG. 18, the values of the respective saturation magnetic flux densities Bs are shown. It is a star chart. FIG. 19 is a table in which the values of initial magnetic permeability μ _i are displayed in a matrix form for the samples of Examples 7 to 9 and Comparative Examples 4 to 15 corresponding to the matrix display of FIG. 18. As a table corresponding to the matrix in which the samples of Example 7, Comparative Example 7, and Comparative Example 12 are deleted from the sample of the matrix display of FIG. 18, each of the initial permeability μ _i values is a star chart. It is the table | surface which displayed the value of the iron loss Pcv of each powder magnetic core by the matrix display corresponding to the matrix display of FIG. 18 about the sample of Examples 7-9 and Comparative Examples 4-15. The table corresponding to the matrix obtained by deleting the samples of Example 7, Comparative Example 7, and Comparative Example 12 from the sample of the matrix display of FIG. 18 is a star chart of the values of the iron loss Pcv of each dust core.

  Next, an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  In addition, the following embodiment exemplifies an apparatus and a method for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, structure, The arrangement is not specified as follows. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

(One embodiment)
As shown in FIG. 1, a composite magnetic grain 1 according to an embodiment of the present invention has a columnar crystal layer 12 mainly composed of iron oxide having a thickness of 1 μm or less on at least a part of the surface of a soft magnetic alloy powder 11. The composite soft magnetic alloy particles. The soft magnetic alloy powder 11 includes at least one of an amorphous alloy powder and a nanocrystalline alloy powder. When element mapping of the cross section of the composite magnetic particle 1 according to one embodiment is measured by an energy dispersive X-ray spectrometer (EDS), the oxygen (O) K-shell electrons shown in FIG. 3 are excited and emitted. As shown in the two-dimensional image of X-rays (K-rays) and the two-dimensional image of iron (Fe) K-rays shown in FIG. 4, the oxygen concentration of the columnar crystal layer 12 is the oxygen concentration of the metal structure of the soft magnetic alloy powder 11. It can be seen that the columnar crystal layer 12 is mainly composed of iron oxide.

  Although no color is displayed in FIG. 3, in the color mapping, a darker portion indicates a higher element concentration. In the color mapping of oxygen displayed in black and white in FIG. 3, the color of the band-shaped region corresponding to the columnar crystal layer 12 containing iron oxide as a main component is the soft magnetic alloy powder 11 on the inner side of the columnar crystal layer 12. It can be seen that it is darker than the color of the area corresponding to. As can be seen from the transmission electron microscope (TEM) photographs shown in FIGS. 2 and 8, the columnar crystal layer 12 is a structure having a large aspect ratio in which the minor axis dimension is 200 nm or less.

  The shape of the composite magnetic particle 1 according to an embodiment of the present invention may be spherical or non-spherical. In the case of a non-spherical shape, it may be a shape having a shape anisotropy such as a scale shape, an elliptical sphere shape, a droplet shape, a needle shape, or an indefinite shape having no special shape anisotropy. The shape of the composite magnetic particle 1 according to an embodiment may be a spherical shape, an elliptical spherical shape, a droplet shape, a needle shape, or the like obtained in the stage of manufacturing the composite magnetic particle 1, or the manufactured composite magnetic particle A shape such as a scale obtained by subjecting the grain 1 to secondary processing may be used. As will be described later, in the composite magnetic grains 1 according to Examples 7 to 8 in FIG. 12 and the like, the thickness of the columnar crystal layer provided on the surface of the spherical soft magnetic alloy powder 11, the minor axis of the columnar crystal layer The dimensions, the oxygen concentration of the columnar crystal layer, etc. are illustrated.

According to the composite magnetic particle 1 according to the embodiment of the present invention, the columnar crystal layer 12 mainly composed of iron oxide is provided on at least a part of the surface of the soft magnetic alloy powder 11, so that the volume of the soft magnetic material is increased. A composite magnetic particle 1 capable of forming a molded body with an increased ratio, reducing the iron loss Pcv of the molded body, and increasing the initial magnetic permeability μ _i and the saturation magnetic flux density Bs, and the composite magnetic particle 1 The magnetic component using the molded object containing can be provided.

  The composite magnetic particle 1 according to an embodiment oxidizes the surface of the soft magnetic alloy powder 11 by heat-treating the soft magnetic alloy powder 11, and has a thickness of 1 μm on at least a part of the surface of the soft magnetic alloy powder 11. The columnar crystal layer 12 mainly composed of the following iron oxide can be formed.

[Production of soft magnetic alloy powder]
In producing the soft magnetic alloy powder 11 used for the composite magnetic grain 1 according to the embodiment of the present invention, first, pure iron (Fe), metallic silicon (Si), ferroboron (Fe-B), phosphorous iron (Fe--). Weigh raw materials such as P), pure copper (Cu), and graphite (C). And the raw material prepared so that it may become the target alloy composition is melt | dissolved at 1400 degreeC in an alumina crucible by a high frequency induction heating method, and a molten metal (alloy molten metal) is produced | generated. The molten metal is cast into a copper mold and cooled to obtain a mother alloy.

  Then, the soft magnetic alloy powder 11 according to the embodiment is manufactured by various powdering methods such as a water atomizing method, a gas atomizing method, a rotating water atomizing method, a spray method, a cavitation method, and a spark erosion method. Atomizing methods such as the water atomizing method, gas atomizing method, and rotating water atomizing method are used to melt the mother alloy with a high-frequency induction heating device and spray the molten mother alloy at a high speed from the nozzle into the molten alloy flow. In this method, the molten alloy is refined and rapidly cooled to make the soft magnetic alloy powder 11 as a metal powder.

  By producing the soft magnetic alloy powder 11 according to one embodiment by such an atomizing method, it is possible to efficiently produce a very small soft magnetic alloy powder 11. Further, according to the atomizing method, the particle shape of the obtained soft magnetic alloy powder 11 becomes close to a spherical shape due to the action of surface tension. For this reason, when a soft magnetic core is manufactured using the soft magnetic alloy powder 11, a product with a high filling rate is obtained. That is, according to the atomization method, it is possible to obtain the soft magnetic alloy powder 11 capable of producing a dust core having a high magnetic permeability μ and a saturation magnetic flux density Bs.

  Among the atomization methods, if the water atomization method is adopted, it is possible to increase the size of the production equipment and increase the tapping rate of the molten alloy, so that mass productivity can be improved. Since the cooling rate is higher than the gas atomization method using an inert gas such as argon or various gases such as nitrogen and air, it is easily amorphized. Further, different media may be used for miniaturization and rapid cooling. In addition, it is easy to obtain an amorphous alloy in the case of a quenched ribbon manufactured by the liquid quenching method, but it is difficult to pulverize the ribbon into a uniform fine flat powder. It is preferable to manufacture the soft magnetic alloy powder 11 according to an embodiment in the form of a plate.

In the following Examples 1 to 6, soft magnetic alloy powder 11 having a median diameter d ₅₀ = 11.0 μm was produced by the rotating water atomizing method (high-speed rotating water atomizing method). According to the rotating water atomization method, the molten metal can be cooled at an extremely high speed, so that the disordered atomic arrangement in the molten metal can be solidified and maintained in a highly maintained state. High soft magnetic alloy powder 11 can be produced efficiently.

For example, as the soft magnetic alloy powder 11 according to one embodiment, an alloy powder containing Fe, Si, B, P, Cu, and C can be manufactured by a rotating water atomization method. Regardless element distribution in the soft magnetic alloy powder 11, when expressed by the composition formula of _{Fe a B b Si c P x} C y Cu z as an aggregate of the soft magnetic alloy powder 11 according to one embodiment,

79 ≦ a ≦ 86 at%,
5 ≦ b ≦ 13 at%,
0 <c ≦ 8 at%,
0 <x ≦ 10 at%,
0 ≦ y ≦ 5 at%,
0.4 ≦ z ≦ 1.4 at%,
0.08 ≦ z / x ≦ 1.2

It is preferable as satisfying one embodiment. In Examples 1 to 6 according to an embodiment, the powder composition a = 85.7 at%, b = 9.5 at%, c = 0.5 at%, x = 3.5 at%, y = 1 at%, z = Soft magnetic alloy powder 11 of (Fe _85.7 Si _0.5 B _9.5 P _3.5 Cu _0.8 ) ₉₉ C ₁ was prepared at _{0.8 at} % and z / x = 0.23.

  In the rotating water flow atomization method, a coolant is ejected and supplied along the inner peripheral surface of the cooling cylinder, and the cooling liquid layer is formed on the inner peripheral surface by swirling along the inner peripheral surface of the cooling cylinder. . On the other hand, a raw material of an amorphous alloy is melted, and a liquid or gas jet is sprayed on the obtained molten metal while naturally dropping the molten metal. Thereby, the molten metal is scattered, and the scattered molten metal is taken into the coolant layer. As a result, the molten metal which has been scattered and pulverized is rapidly cooled and solidified to obtain the soft magnetic alloy powder 11.

  In the measurement by differential scanning calorimetry (DSC), the degree of amorphization of the soft magnetic alloy powder 11 in the non-heat treated state (as-Q) was 83.0 to 84.5%. As shown in FIG. 5, according to the X-ray diffraction measurement result of the soft magnetic alloy powder 11 in the non-heat treated state, it can be confirmed that the soft magnetic alloy powder 11 contains an amorphous phase and an αFe phase. Further, as shown in FIG. 6, according to the TEM observation result of the non-heat treated powder, the soft magnetic alloy powder 11 having a particle size of 10 μm or 20 μm was a mixed phase of dendritic crystal structure and amorphous structure.

[Heat treatment process]
The columnar crystal layer 12 used for the composite magnetic grain 1 according to one embodiment of the present invention shown in FIG. 1 is obtained by heat-treating the soft magnetic alloy powder 11 at 350 to 600 ° C., so that the surface of the soft magnetic alloy powder 11 is acidified. Thus, the columnar crystal layer 12 mainly composed of iron oxide can be formed. In the heat treatment of the soft magnetic alloy powder 11, the heating temperature (° C.) as shown in FIG. 7 is maintained for the samples of Examples 1 to 6 in an argon atmosphere with an infrared lamp heating device. Performed in minutes (minutes) to allow nanocrystallization.

  As shown in FIG. 7, the heating temperatures are 450 ° C. in Example 1 and Example 4, 460 ° C. in Example 2 and Example 5, and 470 ° C. in Example 3 and Example 6. The holding time is 1 minute for Examples 1 to 3, and 10 minutes for Examples 4 to 6.

  As shown in FIG. 8, according to the TEM observation result after the heat treatment of the soft magnetic alloy powder 11 according to one embodiment, the presence of both crystal grains of 60 nm or less and crystal grains of 100 nm or more can be confirmed. It can also be confirmed that the columnar crystal layer 12 mainly composed of iron oxide is present on the surface of the soft magnetic alloy powder 11.

[Molding of dust core]
Examples of the shape of the powder magnetic core according to one embodiment of the present invention include a toroidal type, an FT type, an ET type, an EI type, a UU type, an EE type, an EER type, a UI type, a drum type, a pot type, and a cup type. As described above, these powder magnetic cores can be manufactured by a powder production process for producing the soft magnetic alloy powder 11 and a heat treatment process for producing the composite magnetic grain 1 by heat treating the soft magnetic alloy powder 11 as described above. Thereafter, a core forming step of producing a dust core using the composite magnetic particles 1 is included. That is, the powder magnetic core according to one embodiment mixes the composite magnetic particles 1 according to one embodiment, the binder (binder), and the organic solvent, and supplies the obtained mixture to the molding die, Obtained by pressing and molding.

  Examples of the constituent material of the binder (binder resin) used in the production of the dust core include organic resins such as silicone resins, epoxy resins, phenol resins, polyamide resins, polyimide resins, and polyphenylene sulfide resins. Examples include materials, thermosetting inorganic materials such as magnesium phosphate, calcium phosphate, zinc phosphate, manganese phosphate, phosphate such as cadmium phosphate, and silicate (water glass) such as sodium silicate. However, in the following examples, the phenolic resin is mixed so as to be 3 wt% to obtain granulated powder. These binder resin materials can improve the manufacturability and heat resistance of the dust core.

  Further, the ratio of the binder to the composite magnetic particle 1 is slightly different depending on the intended saturation magnetic flux density Bs, mechanical characteristics, allowable iron loss Pcv, etc. of the produced dust core, but 0.5 mass % Or more and preferably 5% by mass or less, more preferably 1% by mass or more and 3% by mass or less. Thereby, while reliably insulating the particles of the composite magnetic particle 1, the density of the dust core is ensured to some extent, and the saturation magnetic flux density Bs and the permeability μ of the dust core are prevented from significantly decreasing. Can do. As a result, a dust core having a higher saturation magnetic flux density Bs and permeability μ and a lower iron loss Pcv can be obtained.

  The organic solvent for dissolving the binder is not particularly limited as long as it can dissolve the binder. For example, various solvents such as ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, toluene, chloroform, ethyl acetate and the like. Is mentioned.

  Examples of the lubricant for enhancing mold release from the mold include metal stearates such as zinc stearate, aluminum stearate, barium stearate, magnesium stearate, calcium stearate and strontium stearate. These metal stearates can be used alone or in combination of two or more as a lubricant.

  In an example according to one embodiment, zinc stearate is used as a lubricant from the viewpoint of a small so-called spring back. When a lubricant is used, the amount added is preferably 0.1 to 0.9 parts by weight, more preferably 100 parts by weight of the composite magnetic grains 1 with respect to 100 parts by weight of the composite magnetic grains 1. Is 0.3 to 0.7 parts by weight. When the amount of the lubricant is too small, it is difficult to remove the mold from the mold after molding, and molding cracks tend to occur.

  On the other hand, when there is too much lubricant, the molding density is lowered, and the magnetic permeability μ is reduced. When zinc stearate is used as the lubricant, the amount of zinc (Zn) in the obtained powder magnetic core is adjusted within the range of 0.004 to 0.2% by mass, and the addition amount is adjusted. Is preferred. When there is too much content of Zn, there exists a tendency which sufficient intensity | strength as a dust core cannot be acquired.

In the Example which concerns on one Embodiment of this invention, after putting the phenol resin melt | dissolved with the composite magnetic particle 1 and ethanol in the mortar and mixing uniformly by mortar mixing, after obtaining granulated powder of 3 wt% of phenol-type resin, Dry the ethanol. In addition, in order to improve the filling property to a metal mold | die, a coarse aggregate is crushed with a pestle. In an example according to one embodiment, granulated powder was formed under the following conditions:

Alloy powder: 10g
Binder: 0.53g
Lubricant: 0.30g

Kneading time: 10 minutes Drying temperature: 100 ° C
Solvent evaporation time: 30 minutes

  Then, the granulated powder is filled in a toroidal mold having an inner diameter of 8 mm, an outer diameter of 13 mm, and a height of 3 mm, and is formed into a dust core shape by applying a pressure of 1.5 GPa with a hydraulic hand press device. A molded body having a thickness of 3.5 mm was obtained.

  Next, the obtained molded body is heated to cure the binder and obtain a dust core. At this time, although the heating temperature varies slightly depending on the composition of the binder, etc., when the binder is composed of an organic material, it is preferably about 100 ° C. or more and 500 ° C. or less, more preferably 120 ° C. The temperature is about 250 ° C. or lower. In the example according to one embodiment, the heating temperature was set to 160 ° C. Further, although the heating time varies depending on the heating temperature, it is about 0.5 hours or more and 5 hours or less, but in the example according to one embodiment, the heating time is 1 hour.

[Measurement of magnetic properties]
FIG. 9 shows the result of measuring the saturation magnetic flux density Bs of the dust core (molded body) after the heat treatment with a vibrating sample magnetometer (VSM-5-10 manufactured by Toei Kogyo Co., Ltd.). In FIG. 9, the external dimensions and weight of each molded object of Examples 1-6 were measured, and the density of each molded object of Examples 1-6 was computed. The saturated magnetic flux density Bs of the compact is calculated by multiplying the value obtained by dividing the density of each compact of Examples 1 to 6 by the true specific gravity of the soft magnetic powder and the value of the saturation magnetic flux density Bs of the composite magnetic grain 1. ing. The outer dimensions of each molded body of Examples 1 to 6 are obtained by measuring the three points of the outer shape and the inner diameter using a caliper and calculating an average value. In the measurement, the thickness is measured at three points using a micrometer, and the average value is calculated. The relative density of each molded body of Examples 1 to 6 was calculated by measuring the weight of each molded body and dividing the volume by the volume of the molded body calculated from the dimensions of the molded body.

  The relative density of each compact can be calculated by dividing the density of each compact in Examples 1 to 6 by the true specific gravity of the composite magnetic grain 1. The value of the saturation magnetic flux density Bs of the composite magnetic particle 1 was obtained by taking 10 mg of the sample of the composite magnetic particle 1 of Examples 1 to 6, placing the sample on the nonmagnetic adhesive tape, folding the adhesive tape in half, It was formed into a plate shape having a length of 7 mm and a width of 7 mm. Next, using a vibrating sample magnetometer (VSM), the saturation magnetization was measured at a maximum applied magnetic field of 12000 A / m and room temperature (25 ° C.). And saturation magnetic flux density Bs was computed from this measured value and the true specific gravity of each sample of Examples 1-6.

In FIG. 9, the result of measuring the initial permeability (real part of complex relative permeability) μ _i and the iron loss Pcv of the dust core at the same time by winding a conductive member around the dust core according to Examples 1 to 6 is also shown. Show. The initial permeability μ _i is measured after a coated copper wire having a diameter of 0.3 mm is wound as a conductive member around the dust cores according to Examples 1 to 6 to produce a coil component. The number of turns of the primary winding and the secondary winding with the coated copper wire was 32 turns. Using an impedance analyzer 4294A manufactured by Agilent Technology Co., Ltd., the inductance of the coil component at a measurement frequency of 100 kHz was measured, and the initial permeability μ _i was calculated using the dimensions of the molded bodies according to Examples 1-6. . When measuring the iron loss Pcv of the dust core, similarly, a coated copper wire having a diameter of 0.3 mm is wound around the dust core according to Examples 1 to 6, and the coil component is measured for magnetic properties by Iwatatsu Measurement Co., Ltd. The iron loss Pcv of the dust core at an applied magnetic field of 100 mT and a measurement frequency of 100 kHz was measured using an apparatus (BH analyzer SY-8217).

  Regarding Examples 1 to 3 in which the holding time of the heat treatment shown in FIG. 7 is 1 minute, as shown in FIG. 9, the saturation magnetic flux density Bs of Example 1 is 1.72 T, and the saturation magnetic flux density Bs of Example 2 is. = 1.73, and the saturation magnetic flux density Bs of Example 3 is 1.76. On the other hand, with respect to Examples 4 to 6 having a holding time of 1 minute in FIG. 7, the saturation magnetic flux density Bs of Example 4 is 1.77, and the saturation magnetic flux density Bs of Example 5 is 1.77. The saturation magnetic flux density Bs = 1.79. Therefore, the saturation magnetic flux density Bs tends to increase as the heat treatment holding time is longer.

As shown in FIG. 9, an initial permeability mu _i = 14.6 Example 1 for Examples 1-3 of the holding time of 1 minute in FIG. 7, the initial permeability mu _i = 15 in Example 2. 1 and the initial permeability μ _{i of} Example 3 is 15.6, so that when the heating temperature is increased, the initial permeability μ _i tends to increase. On the other hand, with respect to Examples 4 to 6 having a holding time of 1 minute in FIG. 7, the initial permeability μ _i = 14.0 of Example 4 and the initial permeability μ _i = 14.2 of Example 5 were performed. Since the initial permeability μ _{i in} Example 6 is 13.9, when the holding time is long, the tendency of the change in the initial permeability μ _i due to the heating temperature is not recognized.

As can be seen from FIG. 9, the iron loss Pcv of the dust core according to Example 1 is 5344 kW / m ³ for Examples 1 to 3 in which the heat treatment holding time is 1 minute in FIG. Since the iron loss Pcv of the powder magnetic core is 4945 kW / m ³ and the iron loss Pcv of the powder magnetic core according to Example 3 is 4600 kW / m ³ , if the heating temperature is high when the holding time of the heat treatment is short, There is a tendency for the iron loss Pcv of the magnetic core to decrease. On the other hand, for Examples 4 to 6 having a holding time of 1 minute in FIG. 7, the iron loss Pcv of the dust core according to Example 4 is 5190 kW / m ³ and the iron loss Pcv of the dust core according to Example 5 is as follows. = 5731 kW / m ³ and iron loss Pcv of the dust core according to Example 6 = 5710 kW / m ³ , so when the heat treatment holding time is long, the iron core loss Pcv of the dust core due to the heating temperature tends to change It is not allowed.

In order to compare with the measurement results of the dust cores according to Examples 1 to 6, FIG. 11 shows the results of measurement similar to FIG. 9 for Comparative Examples 1 to 3 classified in FIG. Comparative Example 1 is Fe _85.7 Si _0.5 B _9.5 P _3.5 Cu _0.8 ) ₉₉ C ₁ having the same composition as Examples 1 to 6, but is not heat-treated Because of the powder, the columnar crystal layer as shown in FIG. 1 or the like is not formed on the soft magnetic alloy powder. Comparative Example 2 is an Fe-based amorphous material having a composition of (Fe _0.97 Cr _0.03 ) ₇₆ (Si _0.5 B _0.5 ) ₂₂ C ₂ , and Comparative Example 2 is (Fe _0.8 Co _0.2 ) A Fe-based amorphous material having a composition of ₇₅ Si ₄ B ₂₀ Nb ₁ . For the samples of Comparative Examples 1 to 3, as in Examples 1 to 6, the granulated powder was filled in a toroidal mold having an inner diameter of 8 mm, an outer diameter of 13 mm, and a height of 3 mm. By applying a pressure of 5 GPa, it was molded into the shape of a dust core, and the same measurement as in Examples 1 to 6 was performed.

As shown in FIG. 11, the initial permeability μ _i = 16.5 of the dust core of Comparative Example 1 and the initial permeability μ _i = 16.2 of the dust core of Comparative Example 2 are compared. Regarding 1 and 2, the initial permeability μ _i tends to be larger than those in Examples 1-6. On the other hand, since the initial permeability μ _i of the dust core of Comparative Example 3 is 14.6, the initial permeability μ _i is about the same as in Examples 1-6. As can be seen from FIG. 11, the iron loss Pcv of the dust core according to Comparative Example 1 is 5986 kW / m ³ , the iron loss Pcv of the dust core according to Comparative Example 2 is 7850 kW / m ³ , and Comparative Example 3 Therefore, it can be seen that the iron loss Pcv of the dust core is larger than those of Examples 1 to 6. Thus, the iron loss Pcv of the dust core is 7881 kW / m ³ .

FIG. 12 shows the thickness of the columnar crystal layer of the composite magnetic grain 1, the minor axis dimension of the columnar crystal layer, the oxygen concentration of the columnar crystal layer, and the soft magnetic alloy for the samples of Examples 7 to 9 and Comparative Examples 4 to 15. The oxygen concentration of the metal structure of the powder is shown together with the thickness of the insulating layer (SiO ₂ layer). Regarding Examples 7 to 9 and Comparative Examples 4 to 5, there is no insulating layer on the surface of the soft magnetic alloy powder, and in Comparative Examples 6 to 10, the thickness of the insulating layer provided on the surface of the soft magnetic alloy powder is 0. The thickness of the insulating layer in Comparative Examples 11 to 15 is 2 μm. Comparative Examples 4, 6, and 11 have a structure in which the columnar crystal layer is not attached to the composite magnetic grains. FIG. 18 is a table showing a matrix display of the relationship between the thickness of the insulating layer provided on the surface of the soft magnetic alloy powder and the thickness of the columnar crystal layer. FIG. 13 shows the results of measuring the saturation magnetic flux density Bs, the initial permeability μ _i , and the iron loss Pcv of the dust core for the samples of Examples 7 to 9 and Comparative Examples 4 to 15 shown in FIG. Yes.

  FIG. 14 is a diagram showing the relationship between the saturation magnetic flux density Bs and the thickness of the columnar crystal layer in Examples 7 to 9 and Comparative Examples 4 to 15 shown in FIG. As shown in FIG. 14, it can be seen that the values of the saturation magnetic flux density Bs of Examples 7 to 9 are larger than the value of the saturation magnetic flux density Bs of Comparative Examples 4 to 15. In the comparison of Examples 7 to 9, it is recognized that the value of the saturation magnetic flux density Bs decreases as the thickness of the columnar crystal layer increases. Moreover, when the values of the saturation magnetic flux density Bs of Comparative Examples 4 to 15 are compared, it can be seen that the value of the saturation magnetic flux density Bs decreases as the thickness of the insulating layer increases to 0 μm, 0.5 μm, and 2 μm.

  When the matrix display of the saturation magnetic flux density Bs in FIG. 19 is seen from the matrix display of the thickness of the insulating layer and the thickness of the columnar crystal layer in FIG. 18, the value of the saturation magnetic flux density Bs in Examples 7 to 9 without the insulating layer. However, the value of the saturation magnetic flux density Bs is larger than the value of the saturation magnetic flux density Bs of Comparative Examples 4 to 15, and the value of the saturation magnetic flux density Bs tends to decrease as the thickness of the insulating layer increases to 0 μm, 0.5 μm, and 2 μm. The table shown in FIG. 20 corresponds to a matrix obtained by deleting the samples of Example 7, Comparative Example 7, and Comparative Example 12 in which the columnar crystal layer has a thickness of 200 nm from the sample of the matrix display of FIG. In the matrix display of FIG. 20, when the superiority or inferiority of the saturation magnetic flux density Bs is indicated by ◎, ○, Δ, ×, Comparative Example 4 having a structure without an insulating layer and without a columnar crystal layer, and insulation Example 8 with no layer and columnar crystal layer of 500 nm is the highest. In addition, Example 9 in which there is no insulating layer and the columnar crystal layer is 1000 nm is the next highest, which exceeds 1.7T. In comparative examples other than these, all are small and are less than 1.7T. In particular, Comparative Examples 11 to 15 in which the thickness of the insulating layer is 2 μm are extremely small, 1.37T to 1.43T.

FIG. 15 is a diagram showing the relationship between the initial permeability μ _i and the thickness of the columnar crystal layer in Examples 7 to 9 and Comparative Examples 4 to 15 shown in FIG. As shown in FIG. 15, the value of the initial permeability mu _i of Example 7-9, it is found greater than the value of the initial permeability mu _i of the comparative examples 4-15. In the comparison of Examples 7 to 9, it is recognized that the value of the initial permeability μ _i tends to decrease as the thickness of the columnar crystal layer increases. Further, comparing the values of the initial permeability μ _i of Comparative Examples 4 to 15, it can be seen that the value of the initial permeability μ _i decreases as the thickness of the insulating layer becomes 0 μm, 0.5 μm, and 2 μm. .

From the matrix display sample of the insulating layer thickness and the columnar crystal layer thickness of FIG. 18, even if the matrix display of the initial permeability μ _i of FIG. the value of mu _i is greater than the value of the initial permeability mu _i of the comparative examples 4-15, the thickness of the insulating layer is 0 .mu.m, 0.5 [mu] m, in accordance with thicker and 2 [mu] m, the value of the initial permeability mu _i decreases The tendency to do. The table shown in FIG. 22 corresponds to a matrix obtained by deleting the samples of Example 7, Comparative Example 7, and Comparative Example 12 in which the columnar crystal layer has a thickness of 200 nm from the sample of the matrix display of FIG. In the matrix display of FIG. 22, when the superiority or inferiority of the value of the initial magnetic permeability μ _i is indicated by 、, ○, Δ, ×, Example 8 in which there is no insulating layer and the columnar crystal layer is 500 nm is the highest. Comparative Example 4 having no insulating layer and no columnar crystal layer, and Example 9 having no insulating layer and having a columnar crystal layer of 1000 nm are the next largest. In comparative examples other than these, all are small and are less than 1.5. Particularly, Comparative Examples 11 to 15 in which the thickness of the insulating layer is 2 μm are remarkably small as 11.5 to 12.3.

16 and 17 are diagrams showing the relationship between the iron loss Pcv of the dust cores according to Examples 7 to 9 and Comparative Examples 4 to 15 shown in FIG. 13 and the thickness of the columnar crystal layer. FIG. 16 shows an enlarged view of the vicinity (4500 kW / m ^{3 to} 5500 kW / m ³ ) of the iron loss Pcv of FIG. 17 at 5000 kW / m ³ . As shown in FIG. 15, the value of the iron loss Pcv of Example 7 in which the thickness of the columnar crystal layer is as thin as 185 nm is larger than the value of the iron loss Pcv of Comparative Examples 5 to 15, but the thickness of the columnar crystal layer The value of the iron loss Pcv of Example 8 having a thickness of 970 nm and the value of the iron loss Pcv of Example 9 having a columnar crystal layer thickness of 970 nm is the level of the lowest value of the iron loss Pcv of Comparative Examples 4 to 15. . However, as shown in FIG. 17, the value of the iron loss Pcv of the comparative example 4 having the structure without the insulating layer and without the columnar crystal layer is 9120 kW / m ³ and the iron loss Pcv of the examples 7 to 9. Bigger than. Further, when the values of the iron loss Pcv of Comparative Examples 5 to 15 are compared, it can be seen that the value of the iron loss Pcv decreases as the thickness of the insulating layer increases to 0 μm, 0.5 μm, and 2 μm.

  Comparison of the structure having no insulating layer and no columnar crystal layer even when the matrix display of the iron loss Pcv in FIG. 23 is seen from the matrix display of the insulating layer thickness and the columnar crystal layer thickness of FIG. It turns out that the value of the iron loss Pcv of Example 4 is very large. Further, the value of the iron loss Pcv of Example 7 where the thickness of the columnar crystal layer is as thin as 185 nm is larger than the value of the iron loss Pcv of Comparative Examples 5 to 15, but the thickness of the columnar crystal layer is 515 nm. It can be seen that the iron loss Pcv value of 8 and the iron loss Pcv value of Example 9 in which the thickness of the columnar crystal layer is 970 nm are minimum values equivalent to the level of the iron loss Pcv of Comparative Examples 14 and 15. . Furthermore, it can be seen that the value of the iron loss Pcv tends to decrease as the thickness of the insulating layer increases to 0 μm, 0.5 μm, and 2 μm.

The table shown in FIG. 24 corresponds to a matrix in which the samples of Example 7, Comparative Example 7, and Comparative Example 12 in which the thickness of the columnar crystal layer is 200 nm are deleted from the matrix display sample of FIG. In the matrix display of FIG. 24, when the superiority or inferiority of the value of iron loss Pcv is indicated by ◎, ○, Δ, ×, the value of Comparative Example 4 having a structure without an insulating layer and without a columnar crystal layer is 9120 kW / is a large value projects in m ^3. Except for Comparative Example 4, all values are as small as 5020 kW / m ³ or less.

As described above, the condition having the three characteristics of the saturation magnetic flux density Bs, the initial permeability μi, and the iron loss Pcv is the case where there is no insulating layer, the columnar crystal layer has a thickness of 1 μm or less. According to the magnetic component according to one embodiment of the present invention, the surface of the soft magnetic alloy powder 11 is not covered with the insulating layer, and the columnar crystal layer 12 having a thickness of iron oxide as a main component and having a thickness of 1 μm or less is formed. Since the composite magnetic particle 1 provided at least in part is included as a main component, the volume ratio of the soft magnetic material can be increased when a molded body is formed. Therefore, according to the magnetic component according to the embodiment of the present invention, when the molded body is configured, the iron loss Pcv of the molded body can be reduced, and the initial magnetic permeability μ _i and the saturation magnetic flux density Bs can be increased.

(Other embodiments)
As described above, the present invention has been described according to an embodiment. However, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, in the description of the above-described embodiment, the dust core is exemplified as one magnetic component of the present invention, and the coil component in which the conductive member is wound around the dust core has been described. The magnetic component is not limited to a dust core or a coil part product using a dust core. The present invention can be applied to various magnetic parts using magnetic force such as a reactor, a transformer, an inductor, a motor, a noise filter, etc., noise related, and a choke coil.

  In Examples 1 to 9 and the like of the present invention, the structure including the dust core (dust core) that is a magnetic member and the conductive member having a coil shape has been described. However, the magnetic according to the embodiment of the present invention is described. The member may be a magnetic sheet. The magnetic sheet as an example of another magnetic component may include other fixing members such as a double-sided tape. Moreover, the structure by which the coil is embed | buried under the inside of the molded object of a magnetic member may be sufficient. The shape and composition of the conductive member are not limited as long as the conductive member can be embedded in the magnetic member.

  By including the magnetic component according to the embodiment of the present invention, the electric / electronic device according to the embodiment of the present invention can be configured. When the magnetic component according to the embodiment of the present invention includes an inductance element, the device on which the inductance element is mounted corresponds to the electric / electronic device according to the embodiment of the present invention, and the magnetic component according to the embodiment of the present invention. When the component is made of a magnetic sheet, a device in which the magnetic sheet is attached to, for example, a housing or a substrate corresponds to the electric / electronic device according to the embodiment of the present invention. Specifically, a power supply device including a switching power supply, a voltage raising / lowering circuit, a smoothing circuit, an inverter device, a small information device such as a notebook computer or a mobile phone, a thin CRT, a flat panel display, etc. It is illustrated as an electrical / electronic device according to the above.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

  The present invention can be used in the industrial field of manufacturing magnetic parts and in the technical field of manufacturing electrical / electronic devices such as notebook computers, small portable devices, and thin displays using the magnetic components.

DESCRIPTION OF SYMBOLS 1 ... Composite magnetic grain 11 ... Soft magnetic alloy powder 12 ... Columnar crystal layer

Claims (5)

A soft magnetic alloy powder comprising at least one of an amorphous alloy powder and a nanocrystalline alloy powder;
A columnar crystal layer having a thickness of 1 μm or less provided on at least a part of the surface of the soft magnetic alloy powder;
A composite magnetic grain comprising:   The element concentration measurement by an energy dispersive X-ray spectrometer for the cross section of the composite magnetic grain, wherein the oxygen concentration of the columnar crystal layer is higher than the oxygen concentration of the metal structure of the soft magnetic alloy powder. 2. The composite magnetic particle according to 1.   The composite magnetic grain according to claim 1 or 2, wherein the columnar crystal layer has a minor axis dimension of 200 nm or less. The soft magnetic alloy powder is Fe, Si, B, P, Cu, includes C, and when expressed by _{Fe a B b Si c P x} C y Cu composition formula of _z as a collection of powder, 79 ≦ a ≦ 86 at%, 5 ≦ b ≦ 13 at%, 0 <c ≦ 8 at%, 0 <x ≦ 10 at%, 0 ≦ y ≦ 5 at%, 0.4 ≦ z ≦ 1.4 at%, and 0.08 ≦ z / x The composite magnetic grain according to claim 1, wherein a condition of ≦ 1.2 is satisfied.   A magnetic component comprising the composite magnetic particle according to any one of claims 1 to 4 as a main component of a molded body.