JP2021158148A - Powder magnetic core - Google Patents

Abstract

To provide a powder magnetic core with higher performance.SOLUTION: A powder magnetic core 10 includes: a metal magnetic powder 11; and a thermosetting first resin and second resin having a thermosetting property. The second resin has a degree of thermosetting shrinkage higher than that of the first resin; the elasticity when thermosetting is lower than that of the first resin, and the content is less than or equal to the first resin.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a dust core used in inductors such as choke coils and transformers.

In recent years, an automatic driving system (Autonomous Driving System) and an automatic driving support system (Advanced Driver Assistance System) for vehicles have been developed. Behind this was the expansion of sensors mounted on vehicles and the development of highly integrated circuits such as SoCs (System on Chip) for high-speed processing of large amounts of information obtained from those sensors. There is. Inductors used in such applications are required to be compact, compatible with large currents, and have a low DCR.

As the above-mentioned inductor, for example, a metal composite, which is a coil-embedded magnetic element using a dust core produced by pressure-molding a metal magnetic material powder, is known. Since the metal composite uses a metal magnetic powder, it has a high saturation magnetic flux density, is excellent in DC superimposition characteristics, and has a dead spaceless structure, so that it can be miniaturized. As a dust core used for such a metal composite, Patent Document 1 discloses a composite magnetic material in which a metal magnetic powder is bound with a thermosetting resin.

U.S. Patent Application Publication No. 2002-097124

By the way, the above-mentioned conventional composite magnetic material may not have sufficient performance as a dust core. In view of the above, the present disclosure aims to provide a higher performance dust core.

The dust core according to one aspect of the present disclosure includes a metal magnetic material powder and a first resin and a second resin having thermosetting properties, and the second resin has a shrinkage degree at the time of thermosetting. It is higher than one resin, has a lower elasticity at the time of thermosetting than the first resin, and has a content of less than or equal to the first resin.

According to the present disclosure, a higher performance dust core is provided.

FIG. 1 is a schematic perspective view showing a configuration of an electric component including a dust core according to an embodiment. FIG. 2 is an SEM observation image of the dust core according to the embodiment. FIG. 3 is a flowchart showing a method for manufacturing a dust core according to an embodiment. FIG. 4 is a diagram illustrating the effect of adding the epoxy resin according to the embodiment. FIG. 5A is a diagram illustrating the effect on magnetic permeability on the addition of the epoxy resin according to the embodiment. FIG. 5B is a diagram illustrating the effect on strength with respect to the addition of the epoxy resin according to the embodiment.

(Knowledge that led to disclosure)
The dust core is formed by adding a resin material having insulating properties and adhesiveness to the metal magnetic material powder, drying the metal magnetic material powder, and then pressure-molding the powder magnetic material powder in order to obtain insulation and adhesion between the metal magnetic material powders. Made in. In order to enhance the magnetic properties of the dust core, it is important to bring the particles of the metal magnetic powder close to each other. That is, it is important to densely fill the metal magnetic powder.

One of the measures for the above is to increase the pressure during pressure molding. Since the particles of the metallic magnetic powder are pressed against each other according to the pressure, the distance between them is shortened. Further, as another measure, it is possible to reduce the amount of the resin material added. Since the total amount of the resin material is reduced, the amount of the resin material arranged between the particles of the metal magnetic material powder is reduced when averaging is performed, and the filling rate of the metal magnetic material powder is improved.

However, although all of these measures can be filled with the metal magnetic material powder at a high density and are effective for obtaining a dust core having a high magnetic permeability, the binding between the particles of the metal magnetic material powder is broken. Therefore, cracks are likely to occur (mechanical strength or simply decrease in strength). When the pressure during pressure molding is reduced or the amount of the resin material added is reduced in order to suppress the occurrence of cracks, the density of the metal magnetic material powder is reduced, and a powder magnetic core having high magnetic properties is obtained. I can't. That is, there is a trade-off relationship between the strength of the dust core and the magnetic characteristics.

According to the present disclosure, by combining two types of resin materials and binding the particles of the metallic magnetic material powder to each other, the strength of the powder magnetic core is maintained while maintaining the magnetic characteristics regardless of such a trade-off relationship. , Or the magnetic properties of the dust core can be improved while maintaining the strength.

Hereinafter, embodiments will be specifically described with reference to the drawings.

It should be noted that all of the embodiments described below show a specific example of the present disclosure. The numerical values, shapes, materials, components, arrangement positions of the components, connection forms, steps, the order of steps, and the like shown in the following embodiments are examples, and are not intended to limit the present disclosure. Further, among the components in the following embodiments, the components not described in the independent claims will be described as arbitrary components.

(Embodiment)
[composition]
First, an electric component as an example of use of the dust core in the embodiment of the present disclosure will be described with reference to FIG. FIG. 1 is a schematic perspective view showing a configuration of an electric component including a dust core according to an embodiment. FIG. 1 shows an outline of the dust core 10 described later, and further shows the inside of the dust core 10 through the inside. For example, the components such as the coil member 40 hidden by being embedded in the dust core 10 are shown by broken lines, and express that they can be seen through the dust core 10.

As shown in FIG. 1, the electric component 100 includes a dust core 10, a coil member 40, a first terminal member 25, and a second terminal member 35.

As an example, the electric component 100 is a rectangular parallelepiped metal composite, and its approximate outer shape is determined by the shape of the dust core 10. The dust core 10 can be formed into an arbitrary shape by pressure molding. That is, the electric component 100 having an arbitrary shape can be realized depending on the shape of the dust core 10 at the time of pressure molding.

More specifically, the electric component 100 is an inductor, which is a passive element that stores electrical energy flowing between the first terminal member 25 and the second terminal member 35 as magnetic energy by the coil member 40. In the present embodiment, the electric component 100 will be described as one of the usage examples of the dust core 10, but the dust core 10 can be simply used as a magnetic material, and the electric component 100 of the present embodiment can be used. The usage examples are not limited. The dust core 10 may be used in a desired application in which the characteristics of a magnetic material having both high magnetic properties (specifically, high magnetic permeability) and high strength can be utilized.

Here, FIG. 2 is an SEM observation image of the dust core according to the embodiment. FIG. 2 shows an image obtained by observing a cross section of the dust core 10 using an SEM (Scanning Electron Microscope).

As shown in FIG. 2, the dust core 10 in the present embodiment is arranged so as to cover the periphery of the metal magnetic material powder 11 confirmed as a gray grain in the figure and the metal magnetic material powder 11. It is composed of a first resin and a second resin which is scattered around the first resin.

As the metal magnetic material powder 11, Fe-Si-Al-based, Fe-Si-based, Fe-Si-Cr-based, or Fe-Si-Cr-B-based metal magnetic material powder is used. The metal magnetic material powder 11 is useful in use under a large current because it has a higher saturation magnetic flux density than a magnetic material powder such as ferrite.

For example, when Fe-Si-Al-based metal magnetic powder is used, the composition elements are Si in an amount of 8% by weight or more and 12% by weight or less, an Al content of 4% by weight or more and 6% by weight or less, and the rest. The composition element of is composed of Fe and unavoidable impurities. Here, examples of the unavoidable impurities include Mn, Ni, P, S, C and the like. By setting the content of the composition elements that compose the metal magnetic powder 11 within the above composition range, high magnetic permeability and low coercive force can be obtained.

For example, when an Fe—Si-based metal magnetic powder is used, the composition elements consist of Si content of 1% by weight or more and 8% by weight or less, and the remaining composition elements are Fe and unavoidable impurities. The unavoidable impurities are the same as above.

For example, when Fe-Si-Cr-based metal magnetic powder is used, the composition elements include Si in an amount of 1% by weight or more and 8% by weight or less, a Cr content of 2% by weight or more and 8% by weight or less, and The remaining composition elements consist of Fe and unavoidable impurities. The unavoidable impurities are the same as above.

For example, when Fe-S-Cr-B-based metal magnetic powder is used, the composition elements include Si of 1% by weight or more and 8% by weight or less, Cr content of 2% by weight or more and 8% by weight or less, and , The remaining constituent elements consist of Fe and unavoidable impurities. The unavoidable impurities are the same as above.

The role of Si in the composition elements of the above-mentioned metal magnetic powder is to provide the effects of reducing magnetic anisotropy and magnetostriction constant, increasing electrical resistance, and reducing eddy current loss. By setting the Si content in the composition element to 1% by weight or more, the effect of improving the soft magnetic characteristics can be obtained, and by setting it to 8% by weight or less, the decrease in saturation magnetization is suppressed and the DC superimposition characteristic is exhibited. The decrease can be suppressed.

Further, by adding Cr to the metal magnetic powder, it is possible to impart the effect of improving the weather resistance. By setting the Cr content in the composition element to 2% by weight or more, the effect of improving weather resistance can be obtained, and by setting it to 8% by weight or less, deterioration of soft magnetic properties can be suppressed.

The average particle size of these metallic magnetic powders is, for example, 5.0 μm or more and 35 μm or less. From the viewpoint of ensuring the withstand voltage, it is preferable to make the average particle size of the metal magnetic powder small in order to alleviate the electric field concentration between the particles, and by setting the average particle size as described above, a high filling rate is ensured. can do. Further, by setting the average particle size of the metal magnetic powder to 35 μm or less, the core loss can be reduced in the high frequency region, and the eddy current loss can be reduced in particular. The average particle size of the metal magnetic powder is measured by using a laser diffraction / scattering method or the like.

Further, in the present embodiment, the first resin is a silicone resin, and is present at, for example, a portion indicated by an upward white arrow in the figure. The silicone resin mainly exists so as to cover the metal magnetic material powder 11, and electrically insulates the particles of the metal magnetic material powder 11 from each other.

On the other hand, the second resin is scattered in places of the first resin covering the metal magnetic powder 11. In the present embodiment, the second resin is an epoxy resin, and is present at, for example, a portion indicated by a downward white arrow in the figure. Since the epoxy resin mainly has high strength, it contributes to improving the strength of the dust core 10 by being contained in the dust core 10.

As described above, the dust core 10 in the present embodiment is composed of two types of thermosetting resin materials. It should be noted that these two types of thermosetting resins are the second resin having a higher shrinkage than the first resin at the time of heat curing, and the relationship between the second resin having a lower elasticity at the time of heat curing than the first resin. Is not limited to the combination of silicone resin and epoxy resin. Any combination of the first resin and the second resin satisfying the above relationship can be used to form a thermosetting resin used for forming the dust core 10. Further, as the thermosetting resin used in the present invention, it is preferable to select a thermosetting resin whose main agent is a liquid at room temperature.

In addition to the first resin and the second resin, the dust core 10 has a third resin different from the first resin and the second resin, and the insulating property between the particles of the metal magnetic powder is further strengthened. Other substances such as an electric insulating material may be mixed.

With reference to FIG. 1 again, the dust core 10 has a rectangular facing surface on which the first terminal member 25 and the second terminal member 35 are formed, and the four sides of each facing surface are top surfaces. , Bottom surface, and the shape of a substantially square column connected by two sides. In the present embodiment, the bottom surface and the top surface have a rectangular shape having dimensions of 14.0 mm × 12.5 mm, and the separation distance from the bottom surface to the top surface is 8.0 mm.

In the coil member 40, a conducting wire, which is a long conductor covered with an insulating film, is wound (wound portion), and both ends of the conducting wire are connected to the first terminal member 25 and the second terminal member 35, respectively (the winding portion). Lead portions 20 and 30). In the present embodiment, it is assumed that a round conductor having a cross-sectional diameter of 0.65 mm is used as the conductor. The thickness and shape of the conductor are not particularly limited, and a round conductor, a flat conductor having a rectangular cross section, or the like can be appropriately selected and used as long as the conductor can be wound. The winding portion is embedded near the center of the dust core 10. Further, in the lead portions 20 and 30, each of both ends of the conducting wire continuously extends to each of the facing surfaces from the winding portion toward the facing surface, and protrudes to the outside of the dust core 10. Here, a part of the lead portion is extended so as to have a flat shape, and is bent along the facing surface and the bottom surface. The insulating film is peeled off from the stretched portion so that it can be electrically connected to the outside.

The first terminal member 25 and the second terminal member 35 are made of a conductor plate such as phosphor bronze material or copper material. Each of the first terminal member 25 and the second terminal member 35 has a recess near the center along the facing surface, and is configured to be recessed into the dust core 10. Lead portions 20 and 30 are arranged outside the recess, and the lead portions 20 and 30 are electrically connected to the first terminal member 25 and the second terminal member 35. The lead portions 20 and 30 and the first terminal member 25 and the second terminal member 35 are connected by resistance welding or the like. Further, the first terminal member 25 and the second terminal member 35 are bent so as to be inserted toward the inside of the dust core 10, and the first terminal member 25 and the second terminal member 35 are inserted into the dust core 10 at the bent portion. The terminal member 25, the second terminal member 35, and the dust core 10 are fixed.

Further, the first terminal member 25 and the second terminal member 35 are bent together with the lead portions 20 and 30 along the bottom surface of the dust core 10. As a result, the lead portions 20 and 30 are surrounded by the bottom bottom side of the electric component 100 while being held by the first terminal member 25 and the second terminal member 35. That is, the lead portions 20 and 30 can be directly connected to a land (not shown) such as a mounting board on which the electric component 100 is mounted.

note that. The first terminal member 25 and the second terminal member 35 are not essential components. If the lead portions 20 and 30 have the strength to maintain the shape independently, the first terminal member 25 and the second terminal member 35 may not be provided.

[Production method]
Next, the method for manufacturing the powder magnetic core 10 described above will be described with reference to FIG. FIG. 3 is a flowchart showing a method for manufacturing a dust core according to an embodiment. In the production of the dust core 10 according to the present embodiment, first, the metal magnetic material powder 11 containing a predetermined composition element is prepared (preparation step S101). Next, the metallic magnetic material powder 11 and the electrical insulating material are mixed (not shown). Mixing of the electrical insulating material is not an essential requirement in the embodiment, such as when the electrical insulating material is replaced by a resin material to be added later, and the treatment may be skipped. By mixing, the thermosetting resin is mixed in a state where the metal magnetic powder 11 and the electrical insulating material are substantially uniformly dispersed.

Specifically, first, the silicone resin, which is the first resin, is dissolved in a solvent such as IPA (Isopropyl Alcohol) in advance, and then added to the mixture of the metallic magnetic powder 11 and the electric insulating material, and further. Mix (knead) (first mixing step S102). The metal magnetic powder 11 is coated with an electric insulating material and a silicone resin to electrically insulate between the particles.

Next, the epoxy resin, which is the second resin, is dissolved in a solvent such as IPA in advance, and then added to the mixture of the metal magnetic powder 11, the electrical insulating material, and the silicone resin, and further mixed (kneaded). (Second mixing step S103). The thermosetting resin shown above is kneaded by mixing the uncured resin material with a mortar, a mixer, or the like. The ratio of the amount of the silicone resin to the epoxy resin added in the present embodiment is 0.08 or more and 1.00 or less in the epoxy resin / silicone resin ratio.

By heating this mixture at a temperature of 65 ° C. or higher and 150 ° C. or lower, the solvent is evaporated and pulverized to obtain a composite magnetic material having good moldability. Further, by classifying this composite magnetic material to obtain a mixed powder having a particle size within a predetermined range, the moldability can be further improved.

The mixed powder obtained as described above is put into a mold and pressure-molded into a desired shape to obtain a dust core 10 (molding step S104). In the molding step S104, pressure molding is performed within a pressure range of 3 to ^{7 ton / cm 2.}

As described above, in the method for producing the dust core 10 in the present embodiment, the first mixing step S102 and the first mixing step S102 in which the metal magnetic material powder and the first resin before curing having thermosetting property are mixed. After the mixing step S102, the second mixing step S103 for mixing the second resin before curing having thermosetting property and the molding step S104 for pressure molding are included, and the second resin shrinks during thermosetting. The degree is higher than that of the first resin, the elasticity at the time of thermosetting is lower than that of the first resin, and the content is less than or equal to that of the first resin.

The first resin among the thermosetting resins used for the dust core 10 is a silicone resin, which has both insulation and elasticity. Further, after the metal magnetic powder 11 is coated with the first resin, an epoxy resin, which is a second resin having a strength stronger than that of the first resin, is added so as to have a content smaller than that of the first resin. Curing of the second resin occurs after the volume has expanded once. In the process of volume expansion of the second resin, the second resin softens once and is dispersed and scattered inside the first resin.

After that, the shrinkage rate of the second resin during the curing process is larger than that of the first resin, and the distance between the particles of the metal magnetic powder 11 can be reduced during the curing process. In this way, the distance between particles is small and the particles are densely packed. Therefore, in the present embodiment, the dust core 10 having a large magnetic permeability and strength can be obtained. Further, the powder magnetic core 10 to be formed is also imparted with heat resistance, which is a characteristic of silicone resin.

Hereinafter, an example of the dust core 10 based on the above embodiment will be described in detail.

(Example)
In the following examples, the dust core 10 using the Fe—Si—Cr-based metal magnetic material powder having an average particle diameter of 10 μm as the metal magnetic material powder 11 will be described.

A mixed powder was prepared by mixing 100 g of the metallic magnetic material powder with a silicone resin and an epoxy resin at the addition rate shown in FIG. FIG. 4 is a diagram illustrating the effect of adding the epoxy resin according to the embodiment.

The mixed powder was dried under a temperature condition of 80 ° C., then classified and the particle size was adjusted to a predetermined range. The sized mixed powder thus obtained was ^{pressure-molded at room temperature under a pressure of 4 ton / cm 2} , and a ring core having an outer diameter of 14.0 mm, an inner diameter of 10.0 mm, and a thickness of 2.00 mm was formed. Was produced. Further, the powder magnetic core 10 in this example was produced by drying for 2 hours under a temperature condition of 150 ° C. and curing the thermosetting resin.

[First magnetic permeability]
To calculate the initial magnetic permeability, the inductance L at 0 A was measured using an LCR meter, and the initial magnetic permeability μi was obtained from the following equation 1 (measurement frequency 100 kHz).

μi = (L × le) / (μ0 × Ae × n ² ) ・ ・ ・ (1)

Le is the effective magnetic path length, μ0 is the magnetic permeability of the vacuum, Ae is the cross-sectional area, and n is the number of turns of the measurement coil.

[Strength]
In the measurement of strength, ^{pressure molding was performed under a pressure of 4 ton / cm 2} to prepare a pre-curing test piece having a length of 12.0 mm, a width of W12.0 mm and a thickness of T0.70 mm, and then a temperature condition of 150 ° C. The pre-curing test piece was cured by drying for 2 hours in the above, and a test piece was prepared.

A load was applied to the prepared test piece by a three-point bending test at a speed of 0.5 mm / min, and the load applied when the test piece was broken was used as a measured value. From the obtained measured values, the intensity σ (N / mm ² ) was calculated by the following formula 2.

σ = 3 × Pb × Ls / 1WT ² ... (2)

Pb indicates the load (measured value) applied when the test piece was broken, and Ls indicates the distance between fulcrums in mm.

[result]
The test results of each sample prepared in this example will be described with reference to FIGS. 5A and 5B together with FIG.

FIG. 5A is a diagram illustrating the effect on magnetic permeability on the addition of the epoxy resin according to the embodiment. Further, FIG. 5B is a diagram illustrating the effect on strength with respect to the addition of the epoxy resin according to the embodiment. The initial magnetic permeability obtained as a result of the above test is shown as the magnetic permeability in the fifth column of FIG. 4, and the strength [N / mm ² ] obtained as a result of the above test is shown in the sixth column of FIG. Further, in FIG. 5A, corresponding to the fifth column of FIG. 4, a graph showing the magnetic permeability of the sample with respect to the addition rate of the epoxy resin is shown. Further, in FIG. 5B, corresponding to the sixth column of FIG. 4, a graph showing the strength of the sample with respect to the addition rate of the epoxy resin is shown. In the first column of FIG. 4, in addition to the sample number as No, "*" is attached to distinguish the comparative example. For example, the sample of the sample number 1 is given a "*" for comparison. It shows that it is a sample according to an example.

As shown in the samples of sample numbers 1 to 3 in FIG. 4, in a sample containing only a silicone resin as a thermosetting resin, the magnetic permeability decreases as the amount of the thermosetting resin added increases.

On the other hand, as shown in the samples of sample numbers 4 to 10 in FIG. 4, 5A, and 5B, the samples in which the epoxy resin is added in addition to the silicone resin as the thermosetting resin are compared with the samples of sample number 2. Then, the strength increases according to the amount of the epoxy resin added, and the magnetic permeability temporarily increases with the sample of sample number 8 as a peak. Further, the sample of sample number 10 is significantly stronger than the sample of sample number 3 in which the total amount of thermosetting resin added (that is, silicone resin + epoxy resin) is lower, while maintaining the same magnetic permeability. It turns out that it is a high sample.

The result is that by adding the epoxy resin after coating the metal magnetic powder 11 with the silicone resin, the epoxy resin is softened during curing and shrinking, and the epoxy resin is scattered in the silicone resin. caused by. Since the curing shrinkage of the scattered epoxy resins is larger than that of the silicone resin, the distance between the particles of the metal magnetic powder 11 can be reduced during the curing process, and a larger magnetic permeability can be obtained. .. At the same time, it is possible to obtain a dust core 10 having both the high strength of the epoxy resin and the high heat resistance of the silicone resin.

If the ratio of the addition amount of the silicone resin to the epoxy resin is 1 or more in the epoxy resin / silicone resin ratio, the influence of the epoxy resin becomes dominant in the formation of the gap between the metal magnetic material powders, and the magnetic permeability becomes small. .. Therefore, the content of the second resin is preferably less than or equal to that of the first resin. As described above, even if the dust core containing a large amount of epoxy resin is formed, the powder magnetic core having low magnetic permeability is only produced, and there is an appropriate addition range of the epoxy resin.

For example, the sample of sample number 4 is prepared by adding 3.00% by weight of a silicone resin and 0.25% of an epoxy resin and processing the sample. In the sample obtained as a result, in the SEM observation image of the cross section, the area occupancy of the epoxy resin was 2.28%, the area occupancy of the metal magnetic powder was 65.95%, and the area occupancy of the silicone resin was 31.77%. be. Therefore, the area ratio of the sample after preparation of the epoxy resin to the silicone resin is 2.28 / 31.77 = 0.07.

Similarly, the sample of sample number 10 is produced by adding 3.00% by weight of a silicone resin and 3.00% of an epoxy resin for processing. In the sample obtained as a result, in the SEM observation image of the cross section, the area occupancy of the epoxy resin was 19.62%, the area occupancy of the metal magnetic powder was 58.36%, and the area occupancy of the silicone resin was 22.02%. be. Therefore, the area ratio of the sample after preparation of the epoxy resin to the silicone resin is 19.62 / 22.02 = 0.89. That is, the area occupancy of the second resin in the cross section is effective when it is contained at least in a small amount, and exists in the range of 19.62% (that is, 20%) or less. In other words, the area occupancy of the second resin in the cross section may be greater than 0.0% and 20% or less. The area ratio of the second resin to the first resin in the cross section is 0.07 or more, which is larger than 0.0, and 0.89 or less, which is smaller than 0.9. In other words, the area ratio of the second resin to the first resin in the cross section may be in the range of more than 0.0 and less than 0.9.

[Effects, etc.]
As described above, the dust core 10 according to the present embodiment includes the metal magnetic material powder 11 and the first resin and the second resin having thermosetting property, and the second resin has a shrinkage degree at the time of thermosetting. It is higher than the first resin, has lower elasticity at the time of thermosetting than the first resin, and has a content of less than or equal to the first resin.

In such a dust core 10, the second resin scattered in the first resin is dispersed in the first resin, and when the second resin is cured and shrunk, the particles of the metal magnetic powder 11 are brought close to each other. The magnetic permeability of the entire magnetic core 10 can be improved. That is, the magnetic characteristics of the dust core 10 can be improved. Therefore, a higher performance dust core 10 can be realized.

Further, for example, the first resin may be a silicone resin, and the second resin may be an epoxy resin.

According to this, the above-mentioned dust core 10 can be realized by using a silicone resin as the first resin and an epoxy resin as the second resin. Further, the strength of the dust core 10 can be improved due to the high strength property of the epoxy resin. Therefore, a higher performance dust core 10 can be realized.

Further, for example, the area occupancy of the second resin in the cross section of the dust core may be larger than 0.0% and 20% or less.

According to this, the dust core 10 containing the second resin can be formed at an appropriate content. Therefore, a higher performance dust core 10 can be realized within an appropriate range of the content of the second resin.

Further, for example, the area ratio of the second resin to the first resin in the cross section of the dust core may be larger than 0.0 and smaller than 0.9.

According to this, the dust core 10 containing the second resin can be formed in an appropriate area ratio. Therefore, a higher performance dust core 10 can be realized within an appropriate area ratio of the second resin.

(Other embodiments, etc.)
Although the dust core according to the embodiment of the present disclosure has been described above, the present disclosure is not limited to this embodiment.

For example, a coil component using the above-mentioned magnetic material is also included in the present invention. Examples of the coil component include an inductance component such as a reactor for high frequency, an inductor, and a transformer. The present invention also includes a power supply device including the coil components described above.

Further, the present disclosure is not limited to this embodiment. As long as the gist of the present disclosure is not deviated, various modifications that can be conceived by those skilled in the art are applied to the present embodiment, and a form constructed by combining components in different embodiments is also within the scope of one or more embodiments. May be included within.

The magnetic material according to the present disclosure can be applied to a material for a magnetic core of an inductor for high frequencies and a transformer.

10 Powder magnetic core 11 Metal magnetic powder 20, 30 Lead part 25 1st terminal member 35 2nd terminal member 40 Coil member 100 Electrical component

Claims (4)

Metal magnetic powder and
A thermosetting first resin and a second resin are provided.
The second resin is
The degree of shrinkage during thermosetting is higher than that of the first resin.
The elasticity at the time of thermosetting is lower than that of the first resin.
A dust core having a content equal to or less than that of the first resin. The first resin is a silicone resin.
The dust core according to claim 1, wherein the second resin is an epoxy resin. The dust core according to claim 1 or 2, wherein the area occupancy of the second resin in the cross section of the dust core is greater than 0.0% and 20% or less. The dust core according to any one of claims 1 to 3, wherein the area ratio of the second resin to the first resin in the cross section of the dust core is larger than 0.0 and smaller than 0.9.

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