KR20090078858A - Fabrication method of fe-si type soft magnet powder and soft magnet core using the same - Google Patents

Abstract

A manufacturing method for the Fe-Si system soft magnetic powder and a soft magnetic core using the same are provided to make applicable to all kinds of the high-ends soft magnetic since the core loss is less although it uses in the high frequency range. A manufacturing method for the Fe-Si system soft magnetic powder comprises: a step of ball milling the Fe-Si alloy power; and a step of heat-treating the obtained powder. During the ball milling or the thermal process, the step of mixing the pure Fe powder in the Fe-Si alloy power is performed. The ball milling performs to the speed of 400~1000 rpm with 1~100 for hour. The thermal process performs at 500~600°C, under vacuum or the argon gas environment.

Description

Fabrication method of Fe-Si-based soft magnetic powder, and soft magnetic core using the same {Fabrication Method of Fe-Si type soft magnet powder and soft magnet core using the same}

The present invention is excellent in the molding density and low core loss at high frequency, the production of Fe-Si-based soft magnetic powder applicable to various fields, such as high-frequency power supply, transformer, magnetic switching core, electronic devices, etc. where high performance soft magnetic is required A method, and a soft magnetic core using the same.

Soft magnetic products include iron, silicon steel (Fe-Si), soft ferrite, permalloy, sendust, amorphous materials, and the like.

When the soft magnetic products used are classified into frequency ranges, silicon steel sheets and pure iron are used for low frequency, spinel type ferrite, Ni-ferrite, etc. are used for high frequency, and the middle is permalloy, sendust, Co-based amorphous material is filled. High frequency of soft magnetic core is made of powder core, Fe-Si alloy has high permeability and electrical resistance [BD Cullity, CD Graham, Introduction to Magnetic Materials, Wesley-IEEE, 2006; J. Smit, Magnetic Properties of Materials , McGraw-Hill, New York, 1971].

Recently, studies have been made to use a soft magnetic material having a nanostructure as a soft magnetic core for high frequency because it shows good characteristics even at a very high frequency band. However, the metal-based nanostructure soft magnetic core has a problem of high core loss in the frequency region of MHz or higher due to low electrical resistance. Accordingly, there is an urgent need to develop a technology for controlling the interface between the nano-sized grains in order to lower the electrical resistance of the nanostructured soft magnetic core.

The powder core is used for high frequency of about 100kHz or more. At this frequency, the bulk metal material has a large loss, but crushing the metal with fine powder eliminates the eddy current causing the loss. However, even if the powder itself has a high permeability, the permeability is greatly reduced in this process because it is known that the magnetic field of the self-extinguishing magnetic field increases due to the air gap of the insulator.

The powder core is manufactured through a process of coating and molding the surface of the powder, and the relative density thereof is about 80 to 90%, and it is known that powder having nano size and nano structure exhibits superior soft magnetic properties. When using a metal powder having a nano-size and nano-structure, due to the large increase in the specific surface area when manufacturing a soft magnetic core, the friction between powders increases, so that even when a high pressure is applied during molding, it is difficult to have a relative density of 70% or more. As a result, the saturation magnetic flux density is lowered, resulting in a worse core characteristic. Moreover, in the case of Fe-Si alloy powder, Si has a feature of reducing core loss by lowering magnetic anisotropy and increasing electrical resistance.

Republic of Korea Patent Publication No. 2002-64713, referring to the Fe-Si-based alloy core, controlled the content of Si and Fe, Fe-Si-based alloy having 2 to 10 wt% Si, 90 to 98 wt% Fe The manufacture of the core is disclosed.

In addition, Korean Patent Laid-Open No. 2001-76803 discloses a method for producing a soft magnetic core using silicon steel powder, and specifically, a water glass system of 0.1 to 4 wt% based on silicon steel alloy powder containing 5 to 8 wt% of Si and remaining amount of Fe. Insulation coating is performed at least once by adding mixed ceramics, and after adding a lubricant such as Zn, ZnS, Zn-Stearate to 1wt% or less to improve moldability and mold protection, the core is manufactured by high-pressure molding. A method of performing heat treatment at a temperature of 500 to 800 ° C. has been proposed.

However, as the content of Si increases, the brittleness is strong, so that it is difficult to increase the density of cracks and shaped bodies during molding.

Korean Patent Laid-Open No. 2006-81972 proposes a high frequency iron-based soft magnetic powder and a method of manufacturing the soft magnetic core using the same. Specifically, the Fe-Si-based alloy powder is deformed into a plate shape, and then mixed with a binder, press-molded, and an annular soft magnetic core is manufactured by heat treatment.

On the other hand, there has been an attempt to produce a soft magnetic core by using a new method called warm forming by applying high pressure at a high temperature rather than by pressing or cold forming (Hoganas AB, Warm Compaction, North American Hoganas, 1998).

The warm forming method is one of the most recently developed densification methods for sintered parts and was developed by Hogganas, Sweden. The warm forming method is increasing its application range as a solution to the needs of increasing the stability and high post-processing, high density, high degree of complex shape, large product weight and cost reduction. In order to apply the warm molding method, a special lubricant and a binder must be added to the raw material powder. The raw material powder and the mold are molded in a state of being heated at a constant temperature, and the molded body density up to the same density as that of the 2P-2S method is obtained in one molding. It is characterized by what can be obtained [HOGANAS, Handbook for Sintered Components, 4 (1998). J. Japan].

Korean Patent Laid-Open Publication No. 2005-16529 relates to a stainless steel powder composition and a warm molded and sintered body of the composition, and more particularly, to a composition of stainless steel powder (content of Cr, etc.), and the amount of lubricant used for warm molding. And type, type and content of additives, molding temperature and sintering temperature, and limited to stainless powder (Cr 10-30 wt.%) To propose warm forming.

Until now, a method of manufacturing a Fe-Si-based soft magnetic core using warm molding has not been disclosed, and most of them employ a high-pressure molding method for applying high pressure at room temperature.

Therefore, the present inventors adopt a warm forming process using a Fe-Si alloy having excellent high frequency characteristics, and establish a new process condition to overcome the low formability of the alloy to produce a soft magnetic core, 1 kHz to 1 MHz frequency range It was confirmed that it can be used in various types of soft magnetic materials such as expensive permalloy and sendust.

An object of the present invention is to provide a Fe-Si-based soft magnetic powder and a method for producing the same that can increase the molding density of the core molded body having excellent soft magnetic properties.

Another object of the present invention is to provide a soft magnetic core and a method for manufacturing the same, which have low core loss and are applicable to various high performance soft magnetic materials even when used in a high frequency range.

In order to achieve the above object, the present invention

S1) ball milling the Fe-Si alloy powder; And

S2) heat-treating the obtained powder;

It provides a method for producing a Fe-Si-based soft magnetic powder to perform the step of mixing the pure Fe powder to the Fe-Si alloy powder during the ball milling or heat treatment.

In another aspect, the present invention provides a Fe-Si-based soft magnetic powder prepared by the above method.

In addition, the present invention

S1) heat-treating the Fe-Si alloy powder after ball milling, whereby pure Fe powder is mixed with the Fe-Si alloy powder during the ball milling or heat-treatment to produce a Fe-Si-based soft magnetic powder;

S2) mixing the Fe-Si soft magnetic powder with one material selected from a binder, a lubricant, or a mixture thereof; And

S3) It provides a method of producing a Fe-Si-based soft magnetic core comprising the step of warm compacting the obtained powder (warm compaction).

In another aspect, the present invention provides a Fe-Si-based soft magnetic core prepared by the above method.

Fe-Si-based soft magnetic core manufactured according to the present invention has excellent soft magnetic properties and low core loss at high frequency, so products of various fields using high performance soft magnetic, for example, high frequency power supply, transformer, magnetic switching core, Applied to electronic devices.

Hereinafter, the present invention will be described in more detail.

Fe-Si alloy powder is attracting attention as a high frequency powder core material because of its excellent soft magnetic properties. However, due to the brittleness of Si, cracking occurs when forming the core, and the Si content in the Fe-Si alloy cannot be greatly increased due to problems such as low molding density.

Therefore, in the present invention, the pure Fe powder is added to the Fe-Si alloy powder to control the atomic ratio of Si in the overall powder composition to maintain high soft magnetic properties, increase the density of the molded body, and reduce brittleness to reduce the loss after core molding. To prepare a Fe-Si-based soft magnetic powder.

In this case, the Fe-Si alloy powder referred to throughout this specification means a Fe-Si alloy, and the Fe-Si-based soft magnetic powder means a mixed powder in which Fe powder and Fe-Si alloy powder are mixed.

1 is a flow chart showing the manufacturing step of the Fe-Si-based soft magnetic powder according to the present invention.

Referring to Figure 1, Fe-Si-based soft magnetic powder

S1) ball milling the Fe-Si alloy powder; And

S2) heat-treating the obtained powder;

It is prepared through mixing the pure Fe powder to the Fe-Si alloy powder during the ball milling or heat treatment.

First, in step S1), the ball milling of the Fe-Si alloy powder, which is a raw material powder, is performed.

At this time, the Fe-Si alloy powder used as a raw material is not an alloy powder having a low content of Si, but an alloy containing at least 20 atomic% of Si, preferably Fe _1-x Si _x (where 0.2≤x ≤ 0.75).

The ball milling process is prepared by injecting Fe-Si alloy powder into a ball and ball mill and then ball milling in a dry or wet medium.

The ball is not particularly limited in the present invention, a known stainless steel ball, alumina ball or zirconium ball is used, wherein the ball is a raw material powder and a charging ratio (weight ratio) of 10: 1 to 50: 1, preferably The ball mill is performed smoothly by mixing in a weight ratio of 15: 1.

The ball mill apparatus that can be used at this time is not particularly limited in the present invention, and typically, an attritor, a 3-D mixer, a planetary ball mill, a vibratory ball mill, a horizontal ball mill Various ball mill devices such as ball-mills are possible.

The Fe-Si alloy powder is carried out in the above-described ball mill apparatus at a speed of 400 to 1000 rpm for 1 to 100 hours, preferably for 10 to 20 hours. This high energy ball mill process reduces the size of the grains and increases the internal strain due to external energy, thereby optimizing the particles of the Fe—Si alloy powder to be sufficiently finely and uniformly mixed.

The Fe-Si alloy powder obtained after the ball mill process was analyzed by XRD, and as a result, most of the powder had a Fe and Fe ₃ Si phase having a body centered cubic structure and a small amount of hexagonal close. -Packed) It can be seen that consists of the Fe ₅ Si ₃ phase of the structural structure (see Figure 4).

Next, in step S2) the ball-milled Fe-Si alloy powder is heat-treated.

The heat treatment is performed to remove residual stress, and is a necessary process for applying the soft magnetic core to the core used in the high frequency region. In the case of low frequency, even if such heat treatment process is excluded, there is no big difference in the final obtained physical properties, but in the case of high frequency products, there is a big difference in molding density according to frequency.

Preferably, in the present invention, the heat treatment is performed under a vacuum or argon gas atmosphere at 500 to 600 ° C., and the high frequency soft magnetic core is easily cracked or corroded when the heat treatment is not sufficiently performed.

In particular, the present invention adds the pure Fe powder to the Fe-Si alloy powder to produce the Fe-Si-based soft magnetic powder, the Fe-Si alloy powder in any one of the ball mill process or heat treatment process And mixing is possible.

At this time, the content of the pure Fe powder is added in consideration of the ratio of Fe and Si in the final Fe-Si-based soft magnetic powder is obtained, it has a range that can contain at least 30 atomic% or more Si only considering the atomic ratio. Preferably, the Fe: Si of the finally obtained Fe-Si soft magnetic powder has an atomic ratio of 0.7: 0.3 to 0.25: 0.75.

The Fe-Si-based soft magnetic powder prepared through this step has a particle size of 10 to 100 nm, preferably 15 to 20 nm, at the nano level.

Particularly, in the Fe-Si soft magnetic powder according to the present invention, as shown in FIG. 3, Fe powder is present between the Fe-Si alloy powder, that is, the void space between the brittle fine Fe-Si alloy powder (voids). ) Is compactly transformed into ductile Fe powder to have a filled structure. The Fe powder is present between the brittle Fe-Si alloy powders, and has a buffering effect between these alloy powders to improve the molding density, thereby achieving high molding density of at least 80% or more and up to 95%.

Fe-Si-based soft magnetic powder according to the present invention can be applied as a soft magnetic core used in various high frequency products.

This soft magnetic core is obtained through warm compaction using Fe-Si-based soft magnetic powders obtained as described above.

Figure 2 is a flow chart showing a method of manufacturing a soft magnetic core using Fe-Si-based soft magnetic powder according to the present invention.

2, the soft magnetic core is

S1) heat-treating Fe-Si alloy powder after ball milling, in which case Fe-Si-based soft magnetic powder is prepared by mixing pure Fe powder with Fe-Si alloy powder during the ball milling or heat treatment,

S2) mixing the obtained Fe-Si-based soft magnetic powder and one material selected from a binder, a lubricant, or a mixture thereof; And

S3) is produced through the step of warm molding the obtained powder.

First, in step S1), the Fe-Si alloy powder is subjected to heat treatment after ball milling, in which case the Fe-Si soft magnetic powder is prepared by mixing pure Fe powder with Fe-Si alloy powder during the ball milling or heat treatment. Details of this step are as described above in the method for producing the Fe-Si-based soft magnetic powder.

Next, in step S2), the obtained Fe-Si-based soft magnetic powder and one material selected from a binder, a lubricant, or a mixture thereof are mixed.

The binder may be one selected from the group consisting of polyvinylpyrrolidone (PVP), polyester, polyimide, silicone resin, polyamide, polycarbonate, ABS resin, and combinations thereof. Stearates, paraffins, waxes, natural or synthetic fatty derivatives and one selected from the group consisting of these are possible, and polyvinylpyrrolidone is preferably used.

The type and content of the binder and the lubricant are selected in consideration of the molding density and magnetic properties of the soft magnetic core used in the component to be applied, and are used in an amount of 0.2 to 5.0% by weight, preferably 0.5 to 2.0% by weight in the total composition. . If the content thereof is less than the above range, the frictional force between the powders increases and the molding density decreases. On the contrary, if the content exceeds the above range, the magnetic properties are lowered.

In a preferred embodiment of the present invention, polyvinylpyrrolidone is used as a binder, and in the case of polyvinylpyrrolidone, it is dissolved in a solvent to increase wettability when mixed with Fe-Si-based soft magnetic powder and is in a wet state. Mix with. In this case, the solvent may be one selected from the group consisting of water, alcohols, organic solvents, and mixed solvents thereof, and an appropriate solvent may be selected according to a composition used, and the present invention is not limited thereto. This solvent is subsequently removed during the warm forming process.

Next, in step S3) to obtain a soft magnetic core by warm molding the powder obtained.

Warm compaction has an advantage of facilitating plastic deformation by using the yield point drop characteristic according to the temperature rise of the metal. This warm molding adds a special binder or lubricant to the raw material powder and molds the raw material powder and the mold in a state of being heated to a constant temperature to obtain a high level of compact density.

The conditions to be considered in the warm molding should be the setting of the molding temperature, the selection and selection of the optimum binder or lubricant, and the temperature at which the flow of the powder is most optimized. That is, the molding temperature should be within a temperature range lower than the temperature at which the binder or binder mixed with the soft magnetic powder is pyrolyzed, and the molding process is preferably performed under high pressure at the maximum temperature before pyrolysis.

Preferably, the warm molding according to the present invention provides a pressure of 100 MPa to 1 GPa, preferably 300 to 700 MPa for 1 minute to 1 while gradually increasing the temperature in the mold to 120 to 550 ° C, preferably 240 to 480 ° C. It is carried out for a period of time, preferably 10 minutes to 40 minutes. If the warm molding is performed in a range lower than the temperature, pressure and time, the molding (soft magnetic core) may not be sufficiently formed, and thus the molding density may decrease or cracks may occur. Since there is no further increase in effect and it is uneconomical, it performs suitably within the said range.

In this case, the mold may be manufactured in various forms, and thus it may be applied to parts of various fields requiring a soft magnetic core.

The soft magnetic core manufactured through the above-described steps has excellent soft magnetic properties and low core loss at high frequency, so all fields requiring high performance soft magnetic, for example, high frequency power supply, transformer, magnetic switching core, electronic device, etc. It is preferably used.

Hereinafter, preferred examples are provided to aid in understanding the present invention. However, the following examples are merely provided to more easily understand the present invention, and the contents of the present invention are not limited by the examples.

( Example  One) Fe - Si system Soft magnetic  Manufacture of powder

Fe powder having a purity of 99% or more (powder size 10-200 μm) and Fe ₆₇ Si ₃₃ alloy powder (powder size 5-100 μm) were used as raw material powders.

It is sealed to the container in an argon or hydrogen atmosphere in order to refine the raw material powder, and 100 hours of Fe powder and a Fe _{0 .67} Si _{0 .33} ball milling a mixture of the alloy powder to ball milling apparatus for 1 hour at a rotating speed of 400 rpm While varying the time. At this time, the charging ratio of the ball to the powder was carried out at 15: 1.

The resulting mixed powder was mounted on a furnace and subjected to heat treatment at a temperature of 600 ° C. while injecting Ar gas to prepare a Fe—Si-based soft magnetic powder.

( Example  2) Fe - Si system Soft magnetic  Manufacture of powder

Fe-Si-based soft magnetic powder was prepared in the same manner as in Example 1, except that ball milling of the Fe powder and the Fe _0.67 Si _0.33 alloy powder was performed.

( Example  3) Fe - Si system Soft magnetic  Manufacture of core

Poly-vinyl pyrrolidone (PVP) and siloxane resin (dimethyl, phemyl siloxane, methoxy terminated, D3074, Dow Corning) were added to the Fe-Si soft magnetic powder prepared in Example 1 as a binder. In the mixer, the final composition was mixed for 1 hour to 10 hours so that the Fe _0.9 Si _0.1 (average particle size 3㎛, size distribution 0.5 ~ 12㎛). At this time, the binder was dissolved in water as 0.8% by weight so that the binder can be applied to the powder surface.

Next, the mixed powder was subjected to warm molding for 30 minutes while varying the applied pressure from 300 MPa to a maximum of 650 MPa at a die and powder temperature of 240 ° C. to prepare a soft magnetic core molded body.

( Comparative example  One) Cold  Molding Fe - Si Soft magnetic  Manufacture of core

In the same manner as in Example 1, but was carried out for 10 seconds at a preliminary pressure of 100 MPa at room temperature, and cold-molded for 1 minute at a main pressure of 650 MPa to prepare a Fe-Si soft magnetic core molded body.

( Experimental Example  One) Fe - Si system Soft magnetic  Scanning electron micrograph of powder

Figure 4 is a scanning electron micrograph showing the shape of the Fe-Si-based soft magnetic powder obtained after the ball mill in Example 1.

Referring to FIG. 4, the soft magnetic powder has a size of about 1 to 3 μm, and can be seen to have a relatively uniform size. However, the actual particle size was measured at the nano-particle size in the following experimental example.

( Experimental Example  2) Fe - Si system Soft magnetic  Powder XRD  analysis

In this experiment, XRD analysis was performed to measure the crystal structure and average grain size of soft magnetic powder.

Figure 5 is a graph showing the phase analysis of the Fe-Si-based soft magnetic powder according to the ball milling time, Figure 6 is a graph showing the particle size of the Fe-Si-based soft magnetic powder with ball milling time.

5, Fe 5 of the Fe-Si-based soft magnetic powder is Fe ₅ and Fe ₃ Si phase having a body centered Cubic structure and a small amount of hexagonal close-packed structure of Fe ₅ It was confirmed from the XRD pattern analysis that the Si ₃ phase.

Figure 6 shows the grain size calculated by the Hall-Willamson equation of the XRD pattern of Figure 5, it can be seen that the particle size decreases with the ball milling time. Specifically, in the case of the ball milled powder for about 10 hours or more, the particle size is about 10-20 nm, and it is understood that it is preferable to perform the ball mill process for 10 hours in order to produce a core having better soft magnetic properties. Can be.

( Experimental Example  3) Fe - Si system Soft magnetic  Magnetic property measurement of powder

This experiment was performed to investigate the magnetism of Fe-Si soft magnetic powder.

7 is a result of measuring the saturation magnetization and the coercive force of the Fe-Si soft magnetic powder using a Vibration Sample Magnetometer (VSM).

Referring to Figure 7, it can be seen that the Fe-Si-based soft magnetic powder prepared in accordance with the present invention shows an approximation to the saturation magnetization value of the known general Fe _0.9 Si _0.1 alloy composition.

Experimental Example 4 Density Measurement of Soft Magnetic Core Molded Body

This experiment measured the density of the soft magnetic core prepared in Example 3.

8 is a graph showing a density change measured by the Archimedes method (Archimedes' principle) of the soft magnetic core prepared in Example 3. At this time, the density change of the soft magnetic core of Comparative Example 1 is shown for comparison.

Referring to FIG. 8, as a result of measuring the density after warm forming and cold forming, it can be seen that the warm forming according to the present invention can obtain a density improvement of about ¹ to 1.5 g / cm ³ as compared to cold forming.

Experimental Example 5 Measurement of Core Loss of Soft Magnetic Core Molded Body

In this experiment, the core loss of the soft magnetic core prepared in Example 3 was measured in the range of low frequency to high frequency. The core loss was measured in the form of toroids.

9 is a graph showing the core loss of the soft magnetic core with the applied pressure during warm forming.

Referring to FIG. 9, it can be seen that as the applied pressure increases, the loss of the soft magnetic core is reduced. In the case of the soft magnetic core manufactured under the pressure of 650 MPa, the core loss is 30 W / kg in the high frequency range of 1000 kHz. You can see that it is very low.

Fe-Si alloy powder and soft magnetic core prepared according to the present invention is preferably applicable to high-performance soft magnetic components and manufacturing, such as high-frequency power supply, electromagnetic noise removal, magnetic shielding, magnetic switching core, pulse transformer.

1 is a flow chart showing the manufacturing step of the Fe-Si-based soft magnetic powder according to the present invention.

Figure 2 is a flow chart showing the manufacturing step of the soft magnetic core using the Fe-Si-based soft magnetic powder according to the present invention.

Figure 3 is a schematic diagram showing the form of the Fe-Si-based soft magnetic powder according to the present invention.

Figure 4 is a scanning electron micrograph showing the shape of the Fe-Si-based soft magnetic powder obtained after the ball mill in Example 1.

Figure 5 is a graph showing the phase analysis according to the ball milling time of the Fe-Si-based soft magnetic powder.

6 is a graph showing the particle size of the Fe-Si-based soft magnetic powder according to the ball milling time.

7 is a result of measuring the saturation magnetization and the coercive force value of the Fe-Si soft magnetic powder using a Vibration Sample Magnetometer (VSM).

8 is a graph showing a density change measured by the Archimedes method (Archimedes' principle) of the soft magnetic core prepared in Example 3.

9 is a graph showing the core loss of the soft magnetic core with the applied pressure during warm forming.

Claims (18)

S1) ball milling the Fe-Si alloy powder; And S2) heat-treating the obtained powder; Method of producing a Fe-Si-based soft magnetic powder to perform the step of mixing the pure Fe powder to the Fe-Si alloy powder during the ball milling or heat treatment. The method of claim 1, The Fe-Si alloy powder is Fe _{1 - x} Si _x (0.2≤x≤0.75) method of producing a Fe-Si-based soft magnetic powder. The method of claim 1, The ball mill is a method for producing a Fe-Si-based soft magnetic powder that is performed for 1 to 100 hours at a speed of 400 to 1000 rpm. The method of claim 1, The heat treatment is a method of producing a Fe-Si-based soft magnetic powder that is carried out under a vacuum or argon gas atmosphere at 500 ~ 600 ℃. The method of claim 1, The Fe powder is a method of producing a Fe-Si-based soft magnetic powder is added so that the Si: Fe in the final Fe-Si-based soft magnetic powder to satisfy the atomic ratio of 1: 9 to 3: 7. The Fe-Si soft magnetic powder prepared according to any one of claims 1 to 5. The method of claim 6, The Fe-Si soft magnetic powder is a Fe-Si soft magnetic powder having a particle size of 10 to 100 nm. The method of claim 6, The Fe-Si soft magnetic powder is Fe-Si-based soft magnetic powder that Fe powder is present between the Fe-Si alloy powder. S1) heat-treating the Fe-Si alloy powder after ball milling, whereby pure Fe powder is mixed with the Fe-Si alloy powder during the ball milling or heat-treatment to produce a Fe-Si-based soft magnetic powder; S2) mixing the Fe-Si soft magnetic powder with one material selected from a binder, a lubricant, or a mixture thereof; And S3) A method for producing a Fe-Si soft magnetic core comprising the step of warm compacting the obtained powder (warm compaction). The method of claim 9, The Fe-Si alloy powder is Fe _{1 - x} Si _x (0.2≤x≤0.75) method of producing a Fe-Si-based soft magnetic core. The method of claim 9, The ball milling is a method for producing a Fe-Si-based soft magnetic core that is performed for 1 to 100 hours at a speed of 400 to 1000 rpm. The method of claim 9, The heat treatment is a method of producing a Fe-Si-based soft magnetic core that is performed under vacuum or argon gas atmosphere at 500 ~ 600 ℃. The method of claim 9, The Fe powder is a method for producing a Fe-Si soft magnetic core is added so that Fe: Si in the final Fe-Si soft magnetic powder to satisfy the atomic ratio of 0.7: 0.3 to 0.25: 0.75. The method of claim 9, The binder is one selected from the group consisting of polyvinylpyrrolidone (PVP), polyester, polyimide, silicone, polyamide, polycarbonate, ABS resin, and combinations thereof, and the lubricant includes metal stearate, Method for producing a Fe-Si-based soft magnetic core is one selected from the group consisting of paraffin, wax, natural or synthetic fat derivatives and combinations thereof. The method of claim 9, The method of producing a Fe-Si-based soft magnetic core of one selected from the binder, the lubricant, or a mixture thereof in step S2) is used at 0.2 to 5.0% by weight in the total composition. The method of claim 9, The warm forming is a method of producing a Fe-Si soft magnetic core is performed for 1 minute to 1 hour at a pressure of 100 MPa ~ 1GPa while heating the mold to 120 ~ 550 ℃. A Fe—Si based soft magnetic core manufactured by the method according to any one of claims 9 to 16. The method of claim 17, The Fe-Si soft magnetic core is a Fe-Si soft magnetic core having a molding density of 80 to 95%.

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