TW201738908A - Powder core, manufacturing method of powder core, inductor including powder core, and electronic/electric device having inductor mounted therein - Google Patents

Abstract

A powder core includes: a powder of a crystalline magnetic material; and a powder of an amorphous magnetic material, in which a median diameter D50A of the powder of the amorphous magnetic material is 15 [mu]m or less, and satisfies the following expression (1) with respect to a median diameter D50C of the powder of the crystalline magnetic material. 1 ≤ D50A/D50C ≤ 3.5 (1).

Description

Powder core, method for manufacturing the powder core, inductor having the powder core, and electronic/electrical machine to which the inductor is mounted

The present invention relates to a powder core, a method of manufacturing the powder core, an inductor having the powder core, and an electronic/electric machine to which the inductor is mounted. In the present specification, the "inductor" includes a passive element including a core material of a powder core and a coil, and includes a concept of a reactor.

A powder core used in a booster circuit such as a hybrid vehicle, a reactor for power generation/transformation equipment, a transformer, or a krypton or the like can be obtained by powder molding a soft magnetic powder. Inductors equipped with such a powder core are required to have both low iron loss and excellent DC superposition characteristics. Patent Document 1 discloses a method for solving the above problem (both having a low iron loss and excellent DC superposition characteristics), and an inductor is disclosed in which a magnetic powder and a binder are mixed. A coil is integrally embedded in the core formed by pressurization of the mixed powder, and a powder formed by mixing 5 to 20 wt% of the iron-iron alloy aluminum powder in the carbonyl iron powder is used as the magnetic powder. Patent Document 2 discloses an inductor including a magnetic core (powder core) containing an amorphous soft magnetic material of 90 to 98 mass% as an inductor capable of further reducing iron loss. The powder and 2 to 10 mass% of the crystalline soft magnetic powder are blended to form a mixture of the mixed powder and the insulating material. In the core (powder core), the amorphous soft magnetic powder is a material for reducing the solvent loss of the inductor, and the crystalline soft magnetic powder is positioned to increase the filling rate of the mixed powder, increase the magnetic permeability, and exert A material in which an amorphous soft magnetic powder adheres to each other. [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Patent Laid-Open No. Hei. No. 2006-13066 (Patent Document 2) Japanese Patent Laid-Open Publication No. 2010-118486

[Problems to be Solved by the Invention] In Patent Document 1, a powder of a different type of crystalline magnetic material is used as a raw material of a powder core to improve DC superposition characteristics, and in Patent Document 2, a powder of a crystalline magnetic material and The powder of the amorphous magnetic material serves as a raw material of the powder core to reduce the iron loss. However, in Patent Document 2, the evaluation of the DC superposition characteristics is not performed. Accordingly, an object of the present invention is to provide a powder core comprising a powder of a crystalline magnetic material and a powder of an amorphous magnetic material, and an inductor having the powder core can improve DC superposition characteristics and reduce iron loss. Another object of the present invention is to provide a method for producing the above-described powder core, an inductor having the powder core, and an electric/electric machine to which the inductor is attached. [Means for Solving the Problems] In order to solve the above problems, the inventors of the present invention conducted research, and as a result, obtained the following new findings: by appropriately adjusting the particle size distribution and amorphous of the powder of the crystalline magnetic material contained in the powder core The particle size distribution of the powder of the magnetic material can improve the DC superposition characteristic of the inductor having the powder core and reduce the iron loss. In a preferred embodiment, the powder of the crystalline magnetic material contained in the powder core can be exceeded. The DC superposition characteristics of the inductor including the powder core and the iron loss are improved nonlinearly in a range estimated from the mixing ratio of the powder of the amorphous magnetic material. The invention completed by this insight is as follows. One aspect of the present invention is a powder core characterized by comprising a powder of a crystalline magnetic material and a powder of an amorphous magnetic material, wherein the amorphous magnetic material has a powder median diameter D ₅₀ A of 15 The powder median diameter D ₅₀ C of μm or less and the above crystalline magnetic material satisfies the following formula (1). 1≦D ₅₀ A/D ₅₀ C≦3.5 (1) When the particle size distribution of the powder of the crystalline magnetic material contained in the powder core and the particle size distribution of the powder of the amorphous magnetic material satisfy the above relationship, The DC superposition characteristic of the inductor having the powder core can be increased and the nonlinearity can be increased non-linearly beyond the range estimated from the mixing ratio of the powder of the crystalline magnetic material contained in the powder core and the powder of the amorphous magnetic material. Iron loss. It is preferable that the powder median diameter D ₅₀ A of the amorphous magnetic material and the powder median diameter D ₅₀ C of the crystalline magnetic material satisfy the following formula (2). As shown in the following examples, by satisfying the following formula (2), it is easy to make two parameters (μ0 × μ5500 × Isat / ρ and μ0 × Isat / ρ) indicating the DC superposition characteristics are good. 1.2≦D ₅₀ A/D ₅₀ C≦2.5 (2) There is a case where the above amorphous is preferable from the viewpoint of more stably achieving the DC superposition characteristic of the inductor having the powder core and reducing the iron loss. The powder of the magnetic material has a median diameter D ₅₀ A of 7 μm or less. There is a case where the crystal loss of the inductor is more stably achieved from the viewpoint of more stably reducing the iron loss of the inductor than the inductor having the powder core of the powder containing only the amorphous magnetic material. The first mixing ratio is 40% by mass or less based on the mass ratio of the content of the powder of the crystalline magnetic material contained in the powder core to the total content of the powder of the amorphous magnetic material. The first mixing ratio may be 2% by mass or more. The crystalline magnetic material may be selected from the group consisting of Fe-Si-Cr alloys, Fe-Ni alloys, Fe-Co alloys, Fe-V alloys, Fe-Al alloys, Fe-Si alloys, and One or more materials selected from the group consisting of Fe-Si-Al alloys, carbonyl iron, and pure iron. Preferably, the crystalline magnetic material contains an Fe-Si-Cr alloy. The amorphous magnetic material may include one or two or more materials selected from the group consisting of Fe-Si-B alloys, Fe-PC alloys, and Co-Fe-Si-B alloys. Preferably, the amorphous magnetic material contains an Fe-PC alloy. Preferably, the powder of the above crystalline magnetic material comprises an insulating treated material. By applying the insulation treatment, the improvement of the insulation resistance of the powder core and the reduction of the iron loss in the high frequency band are more stably achieved. The powder core may contain a binder component that bonds the powder of the crystalline magnetic material and the powder of the amorphous magnetic material to other materials contained in the powder core. In this case, the above-mentioned bonding component preferably contains a component based on a resin material. Another aspect of the present invention is a method for producing a powder core, which is characterized by the method for producing the powder core, and comprising a forming step of obtaining a shaped article by a forming process, the forming process comprising The powder of the crystalline magnetic material, the powder of the amorphous magnetic material, and the mixture of the binder component containing the resin material are press-formed. By the manufacturing method, the above-described powder core can be manufactured more efficiently. In the above manufacturing method, the molded article obtained by the above-described forming step may be the above-mentioned powder core. Alternatively, it may include a heat treatment step of obtaining the above-mentioned powder core by heat-treating the above-mentioned formed product obtained by the above-described forming step. Still another aspect of the present invention is an inductor comprising: the powder core, a coil, and a connection terminal connected to each end of the coil, and at least a portion of the powder core is located via the connection terminal When the current is supplied to the coil, it is disposed in the induced magnetic field generated by the current. The inductor can have excellent DC superposition characteristics and low loss based on the excellent characteristics of the above-mentioned powder core. Still another aspect of the present invention provides an electronic/electrical device in which the inductor is mounted, and the inductor is connected to a substrate via the connection terminal. As the electronic/electrical device, a power supply device such as a power switch circuit, a voltage raising and lowering circuit, a smoothing circuit, or a small mobile communication device can be exemplified. Since the electric/electrical device of the present invention includes the above-described inductor, it is easy to cope with a large current and a high frequency. [Effects of the Invention] The powder core of the above invention is appropriately adjusted in the particle size distribution of the powder of the crystalline magnetic material and the particle size distribution of the powder of the amorphous magnetic material, so that the inductor having the powder core can be made to increase the direct current. Superposition characteristics and reduced iron loss. Moreover, according to the present invention, there is provided a method for producing the above-described powder core, an inductor having the powder core, and an electronic/electrical device to which the inductor is attached.

Hereinafter, embodiments of the present invention will be described in detail. 1. Powder core The powder core 1 of one embodiment of the present invention shown in Fig. 1 is a ring-shaped toroidal core having a ring shape and containing a powder of a crystalline magnetic material and a powder of an amorphous magnetic material. The powder core 1 of the present embodiment is produced by a production method including a forming process including press forming a mixture containing the powders. The powder core 1 of the present embodiment contains a powder in which a powder of a crystalline magnetic material and a powder of an amorphous magnetic material are adhered to other materials contained in the powder core 1 (in the case of the same material). There are also bonding components for the case of dissimilar materials. (1) Powder of crystalline magnetic material The crystalline magnetic material which provides the powder of the crystalline magnetic material contained in the dust core 1 of one embodiment of the present invention is crystallized (by ordinary X-ray diffraction measurement, A diffraction spectrum having a peak to a degree that can specify a specific material type can be obtained, and a condition of a ferromagnetic body, particularly a soft magnetic material, is not limited to a specific one. Specific examples of the crystalline magnetic material include Fe-Si-Cr alloy, Fe-Ni alloy, Fe-Co alloy, Fe-V alloy, Fe-Al alloy, Fe-Si alloy, and Fe. -Si-Al alloy, carbonyl iron and pure iron. The above crystalline magnetic material may contain either one material or a plurality of materials. The crystalline magnetic material which provides the powder of the crystalline magnetic material is preferably one or more selected from the group consisting of the above materials, and among these, it is preferable to contain an Fe-Si-Cr alloy, and more preferably It is preferable to contain an Fe-Si-Cr alloy. Among the Fe-Si-Cr alloy-based crystalline magnetic materials, a material having a relatively low iron loss Pcv can be obtained, so that even if the content of the powder of the crystalline magnetic material is increased relative to the powder of the crystalline magnetic material in the powder core 1. The mass ratio of the content of the powder to the amorphous magnetic material (also referred to as "the first mixing ratio" in the present specification) does not easily increase the iron loss Pcv of the inductor having the powder core 1. The content of Si and the content of Cr in the Fe-Si-Cr alloy are not limited. As an example of a non-limiting example, the content of Si is set to about 2 to 7 mass%, and the content of Cr is set to about 2 to 7 mass%. The shape of the powder of the crystalline magnetic material contained in the powder core 1 according to the embodiment of the present invention is not limited. The shape of the powder may be spherical or non-spherical. In the case of being non-spherical, it may have a shape having an anisotropic shape such as a scaly shape, an elliptical shape, a droplet shape, or a needle shape, or an amorphous shape having no special shape anisotropy. Examples of the powder of the amorphous shape include a case where a plurality of spherical powders are bonded to each other, or are combined in such a manner as to be partially buried in other powders. Such an amorphous powder is easily observed in carbonyl iron. The shape of the powder may be a shape obtained at the stage of producing the powder, or may be a shape obtained by secondary processing of the produced powder. The shape described in the former may be a spherical shape, an elliptical shape, a droplet shape, or a needle shape, and the shape described in the latter may be scaly. As described below, the particle size of the powder of the crystalline magnetic material contained in the powder core 1 according to the embodiment of the present invention is based on the particle diameter of the powder of the amorphous magnetic material contained in the powder core 1. And set. There is a case where the content of the powder of the crystalline magnetic material in the powder core 1 is preferably such that the first mixing ratio is 40% by mass or less. When the first mixing ratio is 40% by mass or less, it is easy to reduce the iron loss Pcv of the inductor including the powder core 1 when the magnetic material contained in the powder core contains only the amorphous magnetic material. . From the viewpoint of more stably reducing the iron loss Pcv of the inductor including the powder core 1, the first mixing ratio is preferably 35 mass% or less, more preferably 30 mass% or less, and particularly preferably 25% by mass. the following. Preferably, at least a portion of the powder of the crystalline magnetic material comprises a surface-insulated material, and more preferably the powder of the crystalline magnetic material comprises a surface-insulated material. When the surface of the crystalline magnetic material was subjected to surface insulation treatment, the tendency of the insulation resistance of the powder core 1 to rise was found. The type of surface insulation treatment applied to the powder of the crystalline magnetic material is not limited. Phosphoric acid treatment, phosphate treatment, oxidation treatment, and the like can be exemplified. (2) Powder of Amorphous Magnetic Material The amorphous magnetic material which provides the powder of the amorphous magnetic material contained in the powder core 1 of one embodiment of the present invention is amorphous (by ordinary X-ray) In the diffraction measurement, a diffraction spectrum having a peak to a degree that can specify a specific material type cannot be obtained, and a condition of a ferromagnetic body, particularly a soft magnetic material, is not limited to a specific one. Specific examples of the amorphous magnetic material include an Fe—Si—B based alloy, an Fe—P—C based alloy, and a Co—Fe—Si—B based alloy. The amorphous magnetic material may include one material or a plurality of materials. The magnetic material constituting the powder of the amorphous magnetic material is preferably one or more selected from the group consisting of the above materials, and among these, it is preferable to contain an Fe-PC-based alloy, and more preferably contain Fe-PC alloy. Specific examples of the Fe-P-C alloy include a Fe-based amorphous alloy, and the composition of the Fe-based amorphous alloy is Fe._{100 atom % - a - b - c - x - y - z - t} Ni_a Sn_b Cr_c P_x C_y B_z Si_t And 0 atom% ≦a ≦ 10 atom%, 0 atom% ≦b ≦ 3 atom%, 0 atom% ≦ c ≦ 6 atom%, 6.8 atom% ≦ x ≦ 13 atom%, 2.2 atom% ≦ y ≦ 13 Atomic %, 0 atom% ≦z ≦ 9 atom%, 0 atom% ≦t ≦ 7 atom%. In the above composition formula, Ni, Sn, Cr, B, and Si are arbitrary added elements. The addition amount a of Ni is preferably 0 atom% or more and 6 atom% or less, more preferably 0 atom% or more and 4 atom% or less. The addition amount b of Sn is preferably 0 atom% or more and 2 atom% or less, and may be added in a range of 1 atom% or more and 2 atom% or less. The amount c of Cr added is preferably 0 atom% or more and 2 atom% or less, more preferably 1 atom% or more and 2 atom% or less. The addition amount x of P is also preferably 8.8 atom% or more. The addition amount y of C is also preferably 5.8 at% or more and 8.8 at% or less. The amount z of addition of B is preferably 0 atom% or more and 3 atom% or less, more preferably 0 atom% or more and 2 atom% or less. The amount t of addition of Si is preferably 0 atom% or more and 6 atom% or less, more preferably 0 atom% or more and 2 atom% or less. The shape of the powder of the amorphous magnetic material contained in the powder core 1 according to the embodiment of the present invention is not limited. Since the type of the shape of the powder is the same as that of the powder of the crystalline magnetic material, the description thereof is omitted. There is also a case where it is easy to set the amorphous magnetic material into a spherical shape or an ellipsoidal shape in view of the manufacturing method. Further, in general, since the amorphous magnetic material is harder than the crystalline magnetic material, it is preferable to set the crystalline magnetic material to be non-spherical so as to be easily deformed during press molding. The shape of the powder of the amorphous magnetic material contained in the powder core 1 according to the embodiment of the present invention may be a shape obtained at the stage of producing the powder, or may be subjected to secondary processing by the produced powder. And get the shape. The shape described in the former may be a spherical shape, an elliptical shape, or a needle shape, and the shape described in the latter may be scaly. The particle size of the powder of the amorphous magnetic material contained in the powder core 1 according to the embodiment of the present invention is such that the cumulative particle size distribution from the small particle diameter side in the volume-based particle size distribution becomes 50% ( Also referred to as "median particle size" in this specification) D₅₀ A is 15 μm or less. By making the powder of the amorphous magnetic material the median diameter D₅₀ A is 15 μm or less, which is easy to improve the DC superposition characteristics of the powder core 1 and reduce the iron loss Pcv. From the viewpoint of more stably achieving the DC superposition characteristic of the powder core 1 and reducing the iron loss Pcv, there is preferably a powder median diameter D of the amorphous magnetic material.₅₀ When A is 10 μm or less, it is more preferably 7 μm or less, and particularly preferably 5 μm or less. Further, the particle diameter of the powder of the amorphous magnetic material contained in the powder core 1 according to the embodiment of the present invention has the following relationship with the particle diameter of the powder of the crystalline magnetic material contained in the powder core 1. That is, the powder of the amorphous magnetic material has a median diameter D₅₀ Powder and median particle diameter D of crystalline magnetic material₅₀ C satisfies the following formula (1). 1≦D₅₀ A/D₅₀ C≦3.5 (1) by making D₅₀ A/D₅₀ C is in the range of 1 to 3.5, and it is easy to increase the DC superposition characteristic of the inductor having the powder core 1 and reduce the iron loss Pcv. Specifically, the inductor including the powder core 1 can be made nonlinearly beyond the range estimated from the mixing ratio of the powder of the crystalline magnetic material contained in the powder core 1 and the powder of the amorphous magnetic material. Improve DC superposition characteristics and reduce iron loss Pcv. There is preferably a powder of the amorphous magnetic material having a median particle size D₅₀ Powder and median particle diameter D of crystalline magnetic material₅₀ C satisfies the case of the following formula (2). As shown in the following examples, by satisfying the following formula (2), it is easy to make two parameters (μ0 × μ5500 × Isat / ρ and μ0 × Isat / ρ) indicating the DC superposition characteristics are good. 1.2≦D₅₀ A/D₅₀ C≦2.5 (2) If an inductor having a powder core including a magnetic material containing an amorphous magnetic material is compared with an inductor having a powder core having a magnetic material containing a crystalline magnetic material, it is magnetically oriented as a basic tendency. The inductor of the powder core containing the amorphous magnetic material has a lower iron loss Pcv but a lower DC superposition characteristic. Therefore, in general, the magnetic material contained in the powder core is made to contain a crystalline magnetic material and is improved if it contains only an amorphous magnetic material (the first mixing ratio is 0% by mass). In the case of a mixing ratio, the inductor having the powder core tends to have an increase in DC superposition characteristics but an increase in iron loss Pcv. However, in the inductor having the powder core 1 of one embodiment of the present invention, the improvement of the DC superposition characteristic occurs preferentially with the increase of the iron loss Pcv, thereby improving the DC superposition characteristic of the inductor having the powder core 1. And reduce the iron loss Pcv. In the powder core 1 according to a preferred embodiment of the present invention, it has been found that when the first mixing ratio is increased, the iron loss Pcv of the inductor including the powder core 1 tends to decrease. Therefore, in the powder core 1 according to the embodiment of the present invention, as long as the first mixing ratio is about 40% by mass, there is a case where the magnetic material contained in the powder core 1 contains only amorphous material. In the case of a magnetic material (in the case where the first mixing ratio is 0% by mass), the crystal-containing magnetic material is contained to increase the first mixing ratio, and the inductor having the powder core 1 does not increase the iron loss Pcv. Improve DC superposition characteristics. The first mixing ratio is preferably from 1% by mass to 40% by mass, and more preferably from 2% by mass to 40% by mass, from the viewpoint of obtaining such a preferred powder core 1 more stably. In some cases, it is more preferably 5% by mass or more and 40% by mass or less, and particularly preferably 5% by mass or more and 35% by mass or less. (3) Bonding Component The powder core 1 may contain a bonding component that bonds a powder of a crystalline magnetic material and a powder of an amorphous magnetic material to other materials contained in the powder core 1. The binder component is a powder which contributes to the powder of the crystalline magnetic material and the amorphous magnetic material contained in the powder core 1 of the present embodiment (in the present specification, the powders are collectively referred to as "magnetic In the case of powder, the material is fixed, and the composition is not limited. Examples of the material constituting the binder component include organic materials such as a thermal decomposition residue of a resin material and a resin material (referred to collectively as "components based on a resin material" in the present specification), inorganic materials, and the like. Examples of the resin material include an acrylic resin, an anthrone resin, an epoxy resin, a phenol resin, a urea resin, and a melamine resin. A glass-based material such as water glass can be exemplified as the binder component of the inorganic material. The bonding component can comprise either one material or a plurality of materials. The bonding component may also be a mixture of an organic material and an inorganic material. As the bonding component, an insulating material is usually used. Thereby, the insulation as the powder core 1 can be improved. 2. Method for Producing Powder Core The method for producing the powder core 1 according to the embodiment of the present invention is not particularly limited. However, the production method described below can be used to manufacture the powder core 1 with higher efficiency. . A method of manufacturing the powder core 1 according to an embodiment of the present invention includes the forming step described below, and may further include a heat treatment step. (1) Forming Step First, a mixture containing a magnetic powder and a component which provides a binder component in the powder core 1 is prepared. The component which provides the adhesive component (also referred to as "adhesive component" in the present specification) is either in the case of the adhesive component itself or in the case of a material different from the adhesive component. Specific examples of the latter include a case where the binder component is a resin material and a binder component is a thermal decomposition residue thereof. The shaped article can be obtained by a forming process including press forming of the mixture. The pressurization conditions are not limited, and may be appropriately determined depending on the composition of the binder component and the like. For example, in the case where the binder component contains a thermosetting resin, it is preferred to perform heating together with the pressurization to promote the hardening reaction of the resin in the mold. On the other hand, in the case of compression molding, although the pressing force is high, heating is not a necessary condition, and the pressing time is short. Hereinafter, the case where the mixture is a granulated powder and compression-molded will be described in some detail. Since the granulated powder is excellent in rationality, it is possible to improve the workability of the compression molding step which is short in molding time and excellent in productivity. (1-1) Granulated powder The granulated powder contains a magnetic powder and a binder component. The content of the binder component in the granulated powder is not particularly limited. When the content is too low, it is difficult for the binder component to retain the magnetic powder. Further, in the case where the content of the binder component is too low, in the powder core 1 obtained after the heat treatment step, the binder component containing the thermal decomposition residue of the binder component is difficult to insulate the plurality of magnetic powders from each other. On the other hand, when the content of the above-mentioned binder component is too high, the content of the binder component contained in the powder core 1 obtained after the heat treatment step is apt to increase. If the content of the binder component in the powder core 1 becomes high, the magnetic properties of the powder core 1 are liable to lower. Therefore, the content of the binder component in the granulated powder is preferably 0.5% by mass or more and 5.0% by mass or less based on the total amount of the granulated powder. The content of the binder component in the granulated powder is preferably 1.0% by mass or more and 3.5% based on the total amount of the granulated powder, from the viewpoint of lowering the possibility of lowering the magnetic properties of the powder core 1 more stably. The amount of the mass% or less is more preferably 1.2% by mass or more and 3.0% by mass or less. The granulated powder may also contain materials other than the above magnetic powder and binder components. As such a material, a lubricant, a decane coupling agent, an insulating filler, or the like can be exemplified. When a lubricant is contained, the kind is not particularly limited. It can be either an organic lubricant or an inorganic lubricant. Specific examples of the organic-based lubricant include metal soaps such as zinc stearate and aluminum stearate. It is considered that such an organic lubricant is vaporized in the heat treatment step and hardly remains in the powder core 1. The method for producing the granulated powder is not particularly limited. The granulated powder may be directly kneaded, and the obtained kneaded product may be pulverized or the like by a known method to obtain a granulated powder; or a dispersion medium may be added to the above-mentioned components (for example, water may be mentioned) The slurry formed, and then the slurry is dried and pulverized, whereby a granulated powder is obtained. After pulverization, sieving or grading can also be carried out to control the particle size distribution of the granulated powder. As an example of the method of obtaining the granulated powder from the slurry, a method using a spray dryer can be mentioned. As shown in FIG. 2, the rotor 201 is provided in the spray drying apparatus 200, and the slurry S is injected into the rotor 201 from the upper part of the apparatus. The rotor 201 is rotated at a specific number of revolutions, and the slurry S is sprayed in the form of a spray in the form of a spray by centrifugal force in a chamber inside the spray drying device 200. Further, hot air is introduced into the chamber inside the spray drying device 200, whereby the dispersion medium (water) contained in the droplet-shaped slurry S is maintained in a droplet shape and volatilized. As a result, the granulated powder P is formed from the slurry S. The granulated powder P is recovered from the lower portion of the apparatus 200. The parameters such as the number of revolutions of the rotor 201, the temperature of the hot air introduced into the spray drying device 200, and the temperature of the lower portion of the chamber may be appropriately set. As a specific example of the setting range of the parameters, the number of revolutions of the rotor 201 is 4,000 to 8,000 rpm, and the temperature of the hot air introduced into the spray drying device 200 is 130 to 170 ° C, and the temperature at the lower portion of the chamber is 80 to 90. °C. Moreover, the gas environment and the pressure inside the chamber can be appropriately set. As an example, the air chamber is an air environment, and the pressure difference between the pressure and the atmospheric pressure is 2 mmH.₂ O (about 0.02 kPa). The particle size distribution of the obtained granulated powder P can also be controlled by sieving or the like. (1-2) Pressurization Conditions The pressurization conditions at the time of compression molding are not particularly limited. It suffices to appropriately set the composition of the granulated powder, the shape of the molded article, and the like. When the pressing force at the time of compression molding of the granulated powder is too low, the mechanical strength of the molded article is lowered. Therefore, problems such as a reduction in the rationality of the molded article and a decrease in the mechanical strength of the powder core 1 obtained from the molded article are apt to occur. Further, there is a case where the magnetic characteristics of the powder core 1 are lowered or the insulation property is lowered. On the other hand, in the case where the pressing force at the time of compression molding of the granulated powder is too high, it is difficult to produce a molding die capable of withstanding the pressure. The granulated powder is compression-molded from the viewpoint of more stably reducing the possibility that the compression and pressurization step adversely affects the mechanical properties and magnetic gas characteristics of the powder core 1 and is industrially easy to mass-produce. The pressure is preferably 0.3 GPa or more and 2 GPa or less, more preferably 0.5 GPa or more and 2 GPa or less, and particularly preferably 0.8 GPa or more and 2 GPa or less. At the time of compression molding, it may be pressurized while being heated, or may be pressurized at normal temperature. (2) Heat Treatment Step The molded article obtained by the forming step may be the powder core 1 of the present embodiment, and the powder core 1 may be obtained by subjecting the molded article to a heat treatment step as described below. In the heat treatment step, the shaped article obtained by the above-described forming step is heated, thereby correcting the distance between the magnetic powders to adjust the magnetic characteristics, and alleviating the strain imparted to the magnetic powder in the forming step to adjust the magnetic properties. Gas characteristics, thereby obtaining the powder core 1. The purpose of the heat treatment step as described above is to adjust the magnetic characteristics of the powder core 1, and thus the heat treatment conditions such as the heat treatment temperature are set in such a manner as to optimize the magnetic characteristics of the powder core 1. As an example of the method of setting the heat treatment conditions, the heating temperature of the molded article is changed, and other conditions such as the temperature increase rate and the holding time at the heating temperature are fixed. The evaluation criteria of the magnetic gas characteristics of the powder core 1 when the heat treatment conditions are set are not particularly limited. Specific examples of the evaluation item include the iron loss Pcv of the powder core 1. In this case, the heating temperature of the molded article may be set so that the iron loss Pcv of the powder core 1 is the lowest. The measurement conditions of the iron loss Pcv are appropriately set, and as an example, a condition is set in which the frequency is set to 100 kHz and the maximum magnetic flux density Bm is set to 100 mT. The gas atmosphere at the time of heat treatment is not particularly limited. In the case of an oxidizing gas atmosphere, the possibility of excessive thermal decomposition of the binder component and the possibility of progress of oxidation of the magnetic powder are improved. Therefore, it is preferably reduced in an inert gas atmosphere such as nitrogen or argon or hydrogen. The heat treatment is carried out in a gas atmosphere. 3. Inductor, Electronic/Electrical Apparatus An inductor according to an embodiment of the present invention includes the powder core 1, the coil, and the connection terminal connected to each end portion of the coil according to an embodiment of the present invention. Here, at least a part of the powder core 1 is disposed so as to be within an induced magnetic field generated by the current when a current is supplied to the coil via the connection terminal. Since the inductor according to the embodiment of the present invention includes the powder core 1 according to the embodiment of the present invention, it has excellent DC superposition characteristics and is not easily increased even in the case of high-frequency iron loss. Therefore, it can be miniaturized as compared with the prior art inductor. An example of such an inductor is the toroidal coil 10 shown in FIG. The toroidal coil 10 is provided with a coil 2a which is formed by winding a covered conductive wire 2 around a ring-shaped powder core (ring core) 1. The end portions 2d and 2e of the coil 2a can be defined in a portion of the conductive line between the coil 2a composed of the wound coated conductive wire 2 and the end portions 2b and 2c covering the conductive wire 2. As described above, in the inductor of the present embodiment, the member constituting the coil and the member constituting the connection terminal may be formed of the same member. Another example of the inductor according to an embodiment of the present invention includes the coil-embedded inductor 20 shown in Fig. 4 . The coil-embedded inductor 20 can be formed into a sheet shape of a few millimeters (mm) square, and has a powder core 21 having a box shape, and a covered conductive wire 22 is embedded in the coil-embedded inductor 20 The coil portion 22c. The end portions 22a, 22b of the coated conductive wire 22 are located on the surface of the powder core 21 and exposed. One of the surfaces of the powder core 21 is partially covered by the connection ends 23a, 23b which are electrically independent of each other. The connection end portion 23a is electrically connected to the end portion 22a of the covered conductive wire 22, and the connection end portion 23b is electrically connected to the end portion 22b of the covered conductive wire 22. In the coil-embedded inductor 20 shown in FIG. 4, the end portion 22a of the covered conductive wire 22 is covered by the connection end portion 23a, and the end portion 22b of the covered conductive wire 22 is covered by the connection end portion 23b. The method of embedding the coil portion 22c of the conductive wire 22 in the powder core 21 is not limited. The member in which the coated conductive wire 22 is wound may be placed in a mold, and the mixture containing the magnetic powder (granulated powder) may be supplied into the mold and then subjected to press molding. Alternatively, a plurality of members in which a mixture of magnetic powders (granulated powder) is prepared in advance may be prepared, and the members may be combined, and the coated conductive wires 22 may be placed in the void portion defined at this time to obtain an assembly. Then, the assembly is subjected to press molding. The material of the covered conductive wire 22 including the coil portion 22c is not limited. For example, a copper alloy can be cited. The coil portion 22c may also be a side coil. The material of the connection end portions 23a and 23b is also not limited. From the viewpoint of excellent productivity, there is a case where a metal layer formed of a conductive paste such as silver paste or a plating layer formed on the metal layer is preferably used. The material forming the plating layer is not limited. Examples of the metal element contained in the material include copper, aluminum, zinc, nickel, iron, tin, and the like. An electronic/electrical device in which an inductor according to an embodiment of the present invention is mounted on an electronic/electrical device according to an embodiment of the present invention is connected to a substrate via the connection terminal. In the electronic/electrical device according to the embodiment of the present invention, since the inductor according to the embodiment of the present invention is mounted, even if a large current is applied to the device or a high frequency is applied, the function of the inductor is less likely to be lowered or the heat is generated. Causes failure and is easy to miniaturize the machine. The embodiments described above are described in order to facilitate the understanding of the present invention and are not intended to limit the invention. Therefore, the gist of the elements disclosed in the above embodiments also includes all design changes or equivalents within the technical scope of the present invention. [Examples] Hereinafter, the present invention will be specifically described by way of Examples and the like, but the scope of the present invention is not limited to the Examples and the like. (Example 1) (1) Preparation of Fe-based amorphous alloy powder to become Fe_{71 atom %} Ni_{6 atom %} Cr_{2 atom %} P_{11 atom %} C_{8 atom %} B_{2 atom %} In the form of a composition, the raw materials were weighed, and a powder (amorphous powder) of five kinds of amorphous magnetic materials having different particle size distributions was produced by a water atomization method. The particle size distribution of the obtained amorphous magnetic material powder was measured by volume distribution using "Microtrac particle size distribution measuring apparatus MT3300EX" manufactured by Nikkiso Co., Ltd. In the particle size distribution of the volume basis, the cumulative particle size distribution from the small particle size side becomes 50% (median diameter) D₅₀ A is 5 μm. Further, it is prepared to contain an Fe-Si-Cr alloy and the median diameter D₅₀ C is a powder of 2 μm as a powder of a crystalline magnetic material, wherein the Fe-Si-Cr alloy specifically has a content of Si of 6.4% by mass, a content of Cr of 3.1% by mass, and the remainder containing Fe and not An alloy of impurities that is avoided. (2) Preparation of granulated powder The powder of the amorphous magnetic material and the powder of the crystalline magnetic material were mixed so as to have a first mixing ratio shown in Table 1, to obtain a magnetic powder. 97.2 parts by mass of the magnetic powder, 2 to 3 parts by mass of the insulating binder containing the acrylic resin and the phenol resin, and 0 to 0.5 parts by mass of the lubricant containing zinc stearate are mixed in water as a solvent. Slurry. The obtained slurry was granulated under the above conditions using the spray drying apparatus 200 shown in Fig. 2 to obtain a granulated powder. (3) Compression molding The obtained granulated powder was filled in a mold, and subjected to pressure forming at a surface pressure of 0.5 to 1.5 GPa to obtain a ring shape having an outer diameter of 20 mm × an inner diameter of 12 mm × a thickness of 3 mm. Shaped body. (4) Heat treatment The obtained shaped body is placed in a furnace in a nitrogen gas flow environment, and the furnace temperature is heated from room temperature (23 ° C) at a heating rate of 10 ° C / minute to an optimum core heat treatment temperature of 200 to 400 ° C. And maintaining at this temperature for 1 hour, after which heat treatment was carried out in a furnace to cool to room temperature, thereby obtaining a toroidal core including a powder core. [Table 1] (Test Example 1) Measurement of Core Density ρ The size and weight of the toroidal core prepared in Example 1 were measured, and the density ρ (unit: g/cc) of each toroidal core was calculated from these values. The results are shown in Table 1. (Testing Example 2) Measurement of the magnetic permeability The toroidal coil obtained by winding the coated copper wire on the primary side with the toroidal core produced in the first embodiment was wound 40 times on the primary side and 10 times on the secondary side. The initial permeability μ0 was measured at 100 kHz using an impedance analyzer ("4192A" manufactured by HP). Further, a direct current was superimposed on the loop coil at 100 kHz, and the specific magnetic permeability μ5500 when the DC applied magnetic field generated thereby was 5500 A/m was measured. The results are shown in Table 1. (Test Example 3) Measurement of DC superposition characteristics Using a toroidal coil formed of the toroidal core produced in Example 1, a direct current was superimposed on the toroidal coil in accordance with JIS C2560-2. The value L of the inductance L before the (initial) is applied by the amount of change ΔL of the inductance L relative to the superimposed current application₀ Ratio (ΔL/L)₀ When the current value Isat (unit: A) was applied at 30%, the DC superposition characteristic was evaluated. The measurement of the DC superposition characteristics was carried out using "4284" manufactured by HP. The results are shown in Table 1. (Test Example 4) Measurement of Iron Loss Pcv The ring-shaped magnetic core produced in Example 1 was wound 15 times on the primary side and 10 turns on the secondary side, respectively. For the coil, a BH analyzer ("SY-8217" manufactured by Iwasaki Communications Co., Ltd.) was used to measure the iron loss Pcv at a measurement frequency of 2 MHz under the condition that the maximum working magnetic flux density Bm was set to 15 mT. kW/m³ ). The results are shown in Table 1. (Evaluation Example 1) The value of the iron loss Pcv measured by Test Example 4 relative to Pcv, which was normalized by the case where the first mixing ratio was 0% by mass, was evaluated as relative Pcv. By the relative Pcv, even if the type of the crystalline magnetic material and the amorphous magnetic material contained in the powder core (ring core) are different, the change of the iron loss Pcv due to the change of the first mixing ratio can be relatively evaluated. The extent of it. The evaluation results are shown in Table 2. (Evaluation Example 2) μ0 × μ5500 × Isat / ρ The initial magnetic permeability μ0 measured by Test Example 2 and the specific magnetic permeability μ5500 when the DC applied magnetic field was 5500 A/m, and based on Test Examples 1 and 3 And the measured result Isat / ρ (ΔL / L₀ The numerical value of the product of the product of the applied current value Isat divided by the core density ρ measured in Test Example 1 at 30%, that is, μ0×μ5500×Isat/ρ is more suitable for the relative evaluation of DC superposition characteristics than Isat. . The evaluation results are shown in Table 2. Μ0 or μ5500 is a value which is normalized by volume, whereas Isat is a value which is not standardized by volume or mass. Therefore, it is affected by the size of the powder core (ring core). Therefore, by using the parameter of Isat/ρ obtained by dividing Isat by ρ as the evaluation target, the DC superimposition characteristic can be generalized, and the comparison can be easily performed. (Evaluation Example 3) μ0 × Isat / ρ The initial magnetic permeability μ0 measured by Test Example 2 and the numerical value of the product of Isat/ρ based on the results measured by Test Example 1 and Test Example 3, that is, μ0 ×Isat/ρ, like μ0×μ5500×Isat/ρ, is more suitable for relative evaluation of DC superposition characteristics than Isat. The evaluation results are shown in Table 2. [Table 2] (Examples 2 to 10) As shown in Table 3, the particle diameter of the powder using the amorphous magnetic material, the composition of the powder of the crystalline magnetic material, the surface treatment, and the particle diameter were different from those of the magnetic powder used in Example 1. The magnetic powder was obtained in the same manner as in Example 1 to obtain a toroidal core including a powder core. Further, the powder of the amorphous magnetic material used in Example 10 was produced by an atomization method in which gas atomization and water atomization were continuously performed. In Table 3, D₅₀ Column C shows the volume distribution based on the volume distribution of the powder of the crystalline magnetic material measured by the "Microtrac particle size distribution measuring device MT3300EX" manufactured by Nikkiso Co., Ltd. from the small particle size side. The cumulative particle size distribution becomes 50% of the particle diameter (median diameter, unit: μm). [table 3] The meanings of the symbols in Table 3 are as follows: • Composition type A-1: Fe-Si-Cr having a content of Si of 6.4% by mass, a content of Cr of 3.1% by mass, and the remainder containing Fe and unavoidable impurities Alloy (the composition is the same as in Example 1) A-2: Fe-Si-Cr alloy B- having a Si content of 6.3% by mass, a Cr content of 3.2% by mass, and the remainder containing Fe and unavoidable impurities 1: Fe content of 2.0% by mass, content of Cr of 3.5% by mass, and Fe-Si-Cr alloy B-2 containing Fe and unavoidable impurities in the remaining portion: Si content of 3.5% by mass, Cr Fe-Si-Cr alloy having a content of 4.5% by mass and containing Fe and unavoidable impurities C: carbonyl iron, surface treatment type I: no surface treatment (identical to Example 1) II: zinc phosphate system Surface Insulation Treatment III: Surface Insulation Treatment Comprising Phosphoration Regarding Examples 2 to 10, the results of the test examples are shown in Tables 4 to 12, and the results of the evaluation examples are shown in Tables 13 to 21. Further, in the tables, the case where the first mixing ratio is 0% by mass and the case where the first mixing ratio is 100% by mass includes the number of different embodiment numbers from the viewpoint of the conciseness of the improvement table. Case (Example 2-3, Example 3-1, etc.). [Table 4] [table 5] [Table 6] [Table 7] [Table 8] [Table 9] [Table 10] [Table 11] [Table 12] [Table 13] [Table 14] [Table 15] [Table 16] [Table 17] [Table 18] [Table 19] [Table 20] [Table 21] With respect to the above results, the correlation of the relative Pcv with respect to the first mixing ratio and the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio were collectively obtained by way of example, and Figs. 5 to 24 were produced. Fig. 5 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 1. Fig. 6 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 2. Fig. 7 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 3. Fig. 8 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 4. Fig. 9 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 5. Fig. 10 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 6. Figure 11 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 7. Figure 12 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 8. Figure 13 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 9. Figure 14 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 10. Fig. 15 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the first embodiment with respect to the first mixing ratio. Fig. 16 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the second embodiment. Fig. 17 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the third embodiment. Fig. 18 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the fourth embodiment. Fig. 19 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the fifth embodiment with respect to the first mixing ratio. Fig. 20 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the sixth embodiment with respect to the first mixing ratio. Fig. 21 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the seventh embodiment with respect to the first mixing ratio. Fig. 22 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the eighth embodiment with respect to the first mixing ratio. Fig. 23 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the first embodiment with respect to the first mixing ratio. Fig. 24 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the tenth embodiment. Fig. 25 is a graph showing the correlation of μ0 × Isat / ρ in the first embodiment with respect to the first mixing ratio. Fig. 26 is a graph showing the correlation of μ0 × Isat / ρ in the second embodiment with respect to the first mixing ratio. Fig. 27 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in the third embodiment. Fig. 28 is a graph showing the correlation of μ0 × Isat / ρ in the fourth embodiment with respect to the first mixing ratio. Fig. 29 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in the fifth embodiment. Fig. 30 is a graph showing the correlation of μ0 × Isat / ρ in the sixth embodiment with respect to the first mixing ratio. Figure 31 is a graph showing the correlation of μ0 × Isat / ρ in the seventh embodiment with respect to the first mixing ratio. Figure 32 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in Example 8. Figure 33 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in Example 9. Fig. 34 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in the tenth embodiment. In each graph, a quadratic curve to the evaluation result is performed, and the quadratic curve obtained as a result is shown in a solid line in the graph, and a function representing the quadratic curve is expressed (in the formula, x is the first The value of a mixing ratio, y is relative to the value of Pcv, the value of μ0 × μ5500 × Isat / ρ or the value of μ 0 × Isat / ρ is recorded in the vicinity of the graph. By x² The coefficients are compared and the nonlinearity of the curve can be relatively evaluated. Regarding the results of Example 1, the relationship between the iron loss Pcv and μ0 × μ5500 × Isat / ρ and the relationship between the iron loss Pcv and μ0 × Isat / ρ were plotted. The results of these are shown in FIGS. 35 and 36. As shown in FIG. 35 and FIG. 36, before the first mixing ratio becomes 40% by mass, as the first mixing ratio increases, μ0×μ5500×Isat/ρ or μ0×Isat/ρ preferentially rises, and the iron loss Pcv and When the first mixing ratio is 0% by mass, it is equivalent or less. Therefore, it was confirmed that the powder core produced by the first embodiment provides a powder core of an inductor which is particularly excellent in DC superposition characteristics and particularly low in iron loss Pcv and extremely excellent. Regarding the results of Example 10, the relationship between the iron loss Pcv and μ0 × μ5500 × Isat / ρ and the relationship between the iron loss Pcv and μ0 × Isat / ρ were plotted. The results of these are shown in FIGS. 39 and 40. As shown in FIG. 39 and FIG. 40, before the first mixing ratio becomes 30% by mass, as the first mixing ratio increases, μ0×μ5500×Isat/ρ or μ0×Isat/ρ preferentially rises, and the iron loss Pcv and When the first mixing ratio is 0% by mass, it is equivalent or less. However, the powder core produced by the tenth embodiment has a larger value of the iron loss Pcv than the powder core produced by the first embodiment. Think that it is subject to D₅₀ A/D₅₀ C is up to 3.8. From the viewpoints of comparing the results of Examples 1 to 8 and Example 10 in which the composition of the crystalline magnetic material is Fe-Si-Cr-based alloy, the first mixing ratio in the examples is selected as In the case of 30% by mass (Table 22), the relationship between the iron loss Pcv and μ0 × μ5500 × Isat / ρ and the relationship between the iron loss Pcv and μ0 × Isat / ρ were plotted. The results of these are shown in FIGS. 37 and 38. [Table 22] The description of the symbols in Figs. 37 and 38 is as follows. The white circle (○) is a result when the first mixing ratio in each of the examples is 30% by mass. The black diamond (◆) is the result when the first mixing ratio in Examples 1 to 9 is 0% by mass. The white diamond (◇) is the result when the first mixing ratio in Example 10 is 0% by mass. The black triangle (▲) is a result when the first mixing ratio in each of the examples is 100% by mass. The result of the cross (x)-based crystalline magnetic material being carbonyl iron and the first mixing ratio being 5 mass% to 30 mass% (Example 9-2 to Example 9-6). 37 and 38 are lines which are substantially connected to the result when the first mixing ratio is 0% by mass and the result when the first mixing ratio is 100% by mass, on the dotted line or the dotted line. The upper portion, preferably in the case of the upper left side as indicated by the hollow arrows in the respective figures, indicates that a powder core is provided which provides an inductor which exceeds the powder based on the crystalline magnetic material contained in the powder core. The mixing ratio with the powder of the amorphous magnetic material is expected, that is, beyond the simple addition property, the DC superposition property is excellent and the iron loss is lowered. On the other hand, when it is located on the lower side of the broken line of FIG. 37 and FIG. 38, especially when the black arrow in each figure is located on the lower right side, it means that the powder core which provides the following inductor is obtained, which is obtained. The DC superposition characteristics are inferior and the iron loss is increased as compared with the expectation that the powder of the crystalline magnetic material contained in the powder core is mixed with the powder of the amorphous magnetic material. As shown in FIG. 37 and FIG. 38, the result of the embodiment 10-2 is located on the lower right side of the broken line, and the powder core manufactured by the embodiment 10 is not said to provide excellent DC superposition characteristics and reduced iron loss. The powder core of the inductor. It is considered that it is subjected to the same D as the results of FIGS. 39 and 40 described above.₅₀ A/D₅₀ The value of C is as large as 3.8. (Examples 11 and 12) to become Fe_{71 atom %} Ni_{6 atom %} Cr_{2 atom %} P_{11 atom %} C_{8 atom %} B_{2 atom %} In the form of a composition, the raw materials were weighed, and a powder (amorphous powder) of five kinds of amorphous magnetic materials having different particle size distributions was produced by a water atomization method. The particle size distribution of the powder of the obtained amorphous magnetic material was measured by volume distribution using "Microtrac particle size distribution measuring apparatus MT3300EX" manufactured by Nikkiso Co., Ltd. In the particle size distribution of the volume basis, the cumulative particle size distribution from the small particle size side becomes 50% (median diameter) D₅₀ A is 10 μm. The amorphous powder and the median diameter D used in Examples 2 to 10 were prepared.₅₀ A is an amorphous powder of 5 μm, 7 μm and 15 μm. Further, a powder of the following crystalline magnetic material was prepared as the material used in Example 11: Fe-Si containing a content of Si of 3.5% by mass, a content of Cr of 4.5% by mass, and the balance containing Fe and unavoidable impurities. The -Cr alloy is subjected to a treatment corresponding to the surface treatment type II (zinc phosphate-based surface insulation treatment) as a surface treatment, and the median diameter D₅₀ C is 4 μm and 6 μm. Further, a powder of the following crystalline magnetic material was prepared as the material used in Example 12: Fe-Si containing a content of Si of 6.4% by mass, a content of Cr of 3.1% by mass, and the balance containing Fe and unavoidable impurities. -Cr-based alloy (composition type A-1 described above), which was not subjected to surface treatment (corresponding to the above surface treatment type I), and the median diameter D₅₀ C is 2 μm. The powder of the amorphous magnetic material and the powder of the crystalline magnetic material were mixed so that the first mixing ratio became 30% by mass, and the magnetic properties of Examples 11-1 to 11-5 shown in Table 23 were obtained. Powder and magnetic powder of Example 12. The same tests and evaluations as in Examples 2 to 10 were carried out for the magnetic powders. The results are shown in Table 23. [Table 23] Based on the result of Example 11 shown in Table 23, μ0 × μ 5500 × Isat / ρ and D₅₀ A/D₅₀ Relationship between C, and μ0 × Isat / ρ and D₅₀ A/D₅₀ The relationship curve of C is shown in Fig. 41. As shown in Figure 41, in D₅₀ A/D₅₀ When C is 1 or more and 3.5 or less, obtaining μ0 × μ 5500 × Isat / ρ and μ 0 × Isat / ρ is a good result, which tends to D₅₀ A/D₅₀ When C is 1.2 or more and 2.5 or less, it is remarkable. According to the present invention, it is possible to obtain a powder core which provides an excellent inductor having excellent DC superposition characteristics and a reduced iron loss, and it is confirmed by the present embodiment that the degree of goodness is beyond the crystalline magnetic material contained in the powder core. The mixing ratio of the powder and the powder of the amorphous magnetic material is expected. [Industrial Applicability] The inductor including the powder core of the present invention can be used as a component of a booster circuit such as a hybrid vehicle, a component of a power generation/transformation device, a component such as a transformer or a choke coil. And preferably used.

1‧‧‧Powder core (ring core)
2‧‧‧covered conductive wire
2a‧‧‧ coil
2b, 2c‧‧‧ covered end of conductive wire 2
2d, 2e‧‧‧ end of coil 2a
10‧‧‧Circular coil
20‧‧‧Coil-embedded inductors
21‧‧‧Powder core
22‧‧‧coated conductive wire
22a‧‧‧End
22b‧‧‧End
22c‧‧‧ coil department
23a‧‧‧Connected end
23b‧‧‧Connecting end
200‧‧‧ spray drying device
201‧‧‧Rotor
S‧‧‧Slurry
P‧‧‧Powder powder

Fig. 1 is a perspective view conceptually showing the shape of a powder core according to an embodiment of the present invention. Fig. 2 is a view conceptually showing a spray drying apparatus used in an example of a method of producing a granulated powder and an operation thereof. Fig. 3 is a perspective view conceptually showing the shape of an inductor-annular coil as one of the powder cores according to an embodiment of the present invention. Fig. 4 is a perspective view conceptually showing the shape of an inductor-coil embedded inductor including one of the powder cores according to an embodiment of the present invention. Fig. 5 is a graph showing the correlation of the relative Pcv (relative iron loss) in the first embodiment with respect to the first mixing ratio. Fig. 6 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 2. Fig. 7 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 3. Fig. 8 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 4. Figure 9 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 5. Figure 10 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 6. Figure 11 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 7. Figure 12 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 8. Figure 13 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 9. Figure 14 is a graph showing the correlation of relative Pcv with respect to the first mixing ratio in Example 10. Fig. 15 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the first embodiment with respect to the first mixing ratio. Fig. 16 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the second embodiment. Fig. 17 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the third embodiment. Fig. 18 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the fourth embodiment. Fig. 19 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the fifth embodiment with respect to the first mixing ratio. Fig. 20 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the sixth embodiment with respect to the first mixing ratio. Fig. 21 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the seventh embodiment with respect to the first mixing ratio. Fig. 22 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the eighth embodiment with respect to the first mixing ratio. Fig. 23 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ in the first embodiment with respect to the first mixing ratio. Fig. 24 is a graph showing the correlation of μ0 × μ5500 × Isat / ρ with respect to the first mixing ratio in the tenth embodiment. Fig. 25 is a graph showing the correlation of μ0 × Isat / ρ in the first embodiment with respect to the first mixing ratio. Fig. 26 is a graph showing the correlation of μ0 × Isat / ρ in the second embodiment with respect to the first mixing ratio. Fig. 27 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in the third embodiment. Fig. 28 is a graph showing the correlation of μ0 × Isat / ρ in the fourth embodiment with respect to the first mixing ratio. Fig. 29 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in the fifth embodiment. Fig. 30 is a graph showing the correlation of μ0 × Isat / ρ in the sixth embodiment with respect to the first mixing ratio. Figure 31 is a graph showing the correlation of μ0 × Isat / ρ in the seventh embodiment with respect to the first mixing ratio. Figure 32 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in Example 8. Figure 33 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in Example 9. Fig. 34 is a graph showing the correlation of μ0 × Isat / ρ with respect to the first mixing ratio in the tenth embodiment. Fig. 35 is a graph showing the results of plotting the relationship between the iron loss Pcv and μ0 × μ5500 × Isat / ρ as a result of the first embodiment. Fig. 36 is a graph showing the results of plotting the relationship between the iron loss Pcv and the μ0 × Isat / ρ as a result of the first embodiment. 37 is a view showing a comparison between the results of the first embodiment to the eighth embodiment and the tenth embodiment, and the first mixing ratio in each of the examples was selected to be 30% by mass, and the iron loss Pcv and μ0×μ5500× were selected. A graph of the results obtained by plotting the relationship of Isat/ρ. 38 is a view showing the comparison between the results of the first embodiment to the eighth embodiment and the tenth embodiment, and the first mixing ratio in each of the examples was selected to be 30% by mass, and the iron loss Pcv and μ0×Isat/. A graph of the results obtained by plotting the relationship of ρ. Fig. 39 is a graph showing the results of plotting the relationship between the iron loss Pcv and μ0 × μ5500 × Isat / ρ as a result of Example 10. Fig. 40 is a graph showing the results of plotting the relationship between the iron loss Pcv and μ0 × Isat / ρ as a result of Example 10. 41 is a graph showing the relationship between μ0×μ5500×Isat/ρ and D ₅₀ A/D ₅₀ C and the relationship between μ0×Isat/ρ and D ₅₀ A/D ₅₀ C based on the result of Example 11. Figure.

Claims (17)

A powder core comprising: a powder of a crystalline magnetic material and a powder of an amorphous magnetic material, wherein the amorphous magnetic material has a powder median diameter D ₅₀ A of 15 μm or less and The powder median diameter D ₅₀ C of the magnetic material satisfies the following formula (1): 1 ≦ D ₅₀ A/D ₅₀ C ≦ 3.5 (1). The powder core of claim 1, wherein the powder median diameter D ₅₀ A of the amorphous magnetic material and the powder median diameter D ₅₀ C of the crystalline magnetic material satisfy the following formula (2): 1.2≦D ₅₀ A/D ₅₀ C≦2.5 (2). The powder core of claim 1 or 2, wherein the amorphous magnetic material has a powder median diameter D ₅₀ A of 7 μm or less. The powder core of claim 1 or 2, wherein the mass ratio of the content of the powder of the crystalline magnetic material to the sum of the content of the powder of the crystalline magnetic material and the powder of the amorphous magnetic material is A mixing ratio is 40% by mass or less. The powder core of claim 4, wherein the first mixing ratio is 2% by mass or more. The powder core of claim 1 or 2, wherein the crystalline magnetic material comprises a Fe-Si-Cr alloy, an Fe-Ni alloy, an Fe-Co alloy, an Fe-V alloy, and an Fe-Al system. One or more materials selected from the group consisting of alloys, Fe-Si alloys, Fe-Si-Al alloys, carbonyl iron, and pure iron. The powder core of claim 6, wherein the crystalline magnetic material comprises an Fe-Si-Cr alloy. The powder core of claim 1 or 2, wherein the amorphous magnetic material comprises a group selected from the group consisting of Fe-Si-B alloys, Fe-PC alloys, and Co-Fe-Si-B alloys. One or two or more materials. The powder core of claim 8, wherein the amorphous magnetic material comprises an Fe-P-C alloy. The powder core of claim 1 or 2, wherein the powder of the crystalline magnetic material comprises an insulating treated material. The powder core of claim 1 or 2, which comprises a binder component which bonds the powder of the crystalline magnetic material and the powder of the amorphous magnetic material to other materials contained in the powder core. The powder core of claim 11, wherein the bonding component comprises a component based on a resin material. A method for producing a powder core, characterized in that it is a method for producing a powder core according to claim 12, and comprising a forming step of obtaining a shaped article by a forming process, the forming process comprising the above-mentioned crystalline magnetic property Press molding of a powder of a material, a powder of the above amorphous magnetic material, and a mixture of binder components including the above resin material. The method for producing a powder core according to claim 13, wherein the above-mentioned molded article obtained by the above-described forming step is the above-mentioned powder core. The method for producing a powder core of claim 13, which comprises a heat treatment step of obtaining the above-mentioned powder core by heat treatment for heating the above-mentioned shaped article obtained by the above-described forming step. An inductor comprising the powder core of claim 1 or 2, a coil, and a connection terminal connected to each end of the coil, and at least a portion of the powder core is located to the coil via the connection terminal When the current is supplied, it is configured in the induced magnetic field generated by the above current. An electronic/electrical device in which an inductor according to claim 16 is mounted, and the inductor is connected to a substrate via the connection terminal.