TW201824304A - Magnetic material and magnetic component employing the same - Google Patents

Abstract

A magnetic material is provided. The magnetic material includes a core portion consisting of above 99 wt% of Fe, based on the total weight of the core portion. An alloy layer including a FeM alloy is disposed on the surface of the core portion, wherein M is Cr, Si, Al, Ti, Zr, or a combination thereof. An oxide layer including M and an oxide of M is disposed on the surface of the alloy layer. A magnetic component is also provided. The magnetic component includes a sintered product of the magnetic material and a metal.

Description

 Magnetic material and magnetic component including the same  

The disclosure relates to a magnetic material and a magnetic component comprising the same.

With the demand for miniaturization of electronic devices such as smart phones and tablets, the inductors are also miniaturized, and the required frequency and withstand current are also increased. In order to meet such demands, the literature has now used metals to replace commonly used metal oxides (such as iron oxides) as magnetic materials for inductors to increase magnetic permeability, saturation magnetization, and withstand current.

Most of the metals currently used as magnetic materials are alloys, and their magnetic properties are inferior to those of pure metal materials (eg, saturation magnetization (emu/g): FeSi=205, NiFeMo=80-160<pure Fe=217). However, when applied to a laminated inductor, the magnetic material needs to be co-fired with silver and cannot form an electrical path with silver. However, the pure metal is easily partially oxidized by the high-temperature co-firing process, causing the magnetic properties to be degraded and forming a flux with silver. The circuit loses its inductor characteristics.

Therefore, there is a need for a magnetic material having higher performance, which is applicable not only to a conventional wound inductor but also to a cofired laminated inductor or other type of magnetic component.

According to an embodiment, the present disclosure provides a magnetic material comprising: a core body comprising 99 wt% or more of Fe, based on the total weight of the core body; an alloy layer on the surface of the core body, including a FeM alloy, wherein M is Cr, Si, Al, Ti, Zr, or a combination thereof; and a mixed layer on the surface of the alloy layer, including oxides of M and M.

According to an embodiment, the present disclosure provides a magnetic material comprising: a core body comprising 99 wt% or more of Fe, based on the total weight of the core body; a first passivation layer on the surface of the core body, including FeM alloy An oxide, wherein M is Cr, Si, Al, Ti, Zr, or a combination thereof; and a second passivation layer on the surface of the first passivation layer, including an M oxide.

According to another embodiment, the present disclosure provides a magnetic component comprising a magnetic material of the foregoing and a sintered metal.

The above and other objects, features, and advantages of the present invention will become more apparent and understood.

1, 2, 3, 4‧‧‧ magnetic particles

10, 20, 30, 40‧‧‧ core subjects

12, 32‧‧‧ alloy layer

14, 34‧‧‧ mixed layer

22, 42‧‧‧ first passivation layer

24, 44‧‧‧ second passivation layer

100‧‧‧First particle

200‧‧‧Second particles

I‧‧‧First area

II‧‧‧Second area

III‧‧‧ Third Area

1 is a schematic cross-sectional view showing a magnetic material according to an embodiment of the present disclosure.

2 is a schematic cross-sectional view showing a magnetic material according to another embodiment of the present disclosure.

3A-3C are schematic views showing an intermediate process for manufacturing a magnetic material according to an embodiment of the present disclosure.

Fig. 4 is a view showing magnetic permeability of a magnetic material according to some comparative examples and examples.

Fig. 5 is a view showing magnetic permeability of a magnetic material according to some comparative examples and examples.

Fig. 6A is a cross-sectional view showing a magnetic material of an embodiment of the present invention observed by a scanning electron microscope (SEM).

Fig. 6B is an enlarged view of a region indicated by a square in Fig. 6A.

Fig. 7A is a cross-sectional view showing a magnetic material of another embodiment of the present invention observed by a scanning electron microscope (SEM).

Figure 7B is an enlarged view of the area shown in the box in Figure 7A and the results of the EDS-Line Scan.

Fig. 8A is a cross-sectional view of the magnetic element of Comparative Example 3 obtained by a scanning electron microscope (SEM).

Fig. 8B is a cross-sectional view showing the magnetic element of the embodiment of the present invention observed by a scanning electron microscope (SEM).

Fig. 8C is a cross-sectional view showing the magnetic element of another embodiment of the present invention observed by a scanning electron microscope (SEM).

Several different embodiments are set forth below in light of the different features disclosed herein. The specific elements and arrangements in the disclosure are intended to be simplified, but the disclosure is not limited to the embodiments. For example, a description of forming a first element on a second element can include an embodiment in which the first element is in direct contact with the second element, and also includes having additional elements formed between the first element and the second element such that An embodiment in which one element is not in direct contact with the second element. In addition, for the sake of brevity, the disclosure is represented by repeated element symbols and/or letters in different examples, but does not represent a particular relationship between the various embodiments and/or structures.

The disclosed embodiments provide a magnetic material having a high magnetic permeability and a high saturation magnetization, and a magnetic member obtained by co-sintering the magnetic material with a metal. The internal metal material is protected by the metal alloy passivation layer on the surface of the magnetic material, thereby avoiding the problem that the internal metal material is degraded due to oxidation.

An embodiment of the present invention provides a magnetic material 1, as shown in FIG. 1, comprising: a core body 10; an alloy layer 12 on the surface of the core body 10; and a mixed layer 14 on the surface of the alloy layer 12. The particle diameter of the magnetic material 1 may be, for example, 0.5 to 50 μm or 50 to 110 μm.

The core body 10 contains 99% by weight or more of Fe, based on the total weight of the core body 10. In an embodiment, the core body 10 comprises only the metallic element Fe, ie 100% by weight of Fe. In another embodiment, the core body 10 may comprise an oxide of Fe and Fe, wherein the oxide of Fe may include ferrous oxide (FeO), ferric oxide (Fe ₂ O ₃ ), and triiron tetroxide (Fe). ₃ O ₄ ), or a combination of the foregoing. In this embodiment, the content of Fe may be 99 wt% or more, for example, 99 wt%, 99.95 wt%, or 99.99 wt%, and the content of Fe oxide may be 1 wt% or less, for example, 0.01 wt%, 0.05 wt. %, or 1 wt%, based on the total weight of the core body 10.

Alloy layer 12 may comprise an FeM alloy wherein M is Cr, Si, Al, Ti, Zr, or a combination of the foregoing. The content of M in the alloy layer 12 may be 5 to 80% by weight based on the total weight of the FeM alloy. If the content of M is too low, for example, less than 5% by weight, the core body is liable to form oxides, resulting in a decrease in the overall magnetic properties; if the content of M is too high, for example, more than 80% by weight, the magnetic properties of M are worse than Fe. This causes the overall magnetic properties to drop too much. The alloy layer 12 may have a thickness of 0.05 to 10 μm, for example, 0.1 μm, 0.3 μm, 1.5 μm, 3 μm, or 5 μm.

The mixed layer 14 may include oxides of M and M, where M is Cr, Si, Al, Ti, Zr, or a combination of the foregoing. The mixed layer 14 has a thickness ranging from 0.05 to 10 μm, for example, 0.1 μm, 0.3 μm, 1.5 μm, 3 μm, or 5 μm. If the thickness of the mixed layer 14 is too thin, for example, less than 0.05 μm, the passivation layer cannot be formed after the subsequent sintering at 450 to 900 ° C, and the effective magnetic component cannot be formed by co-firing with silver; if the thickness of the mixed layer 14 is too thick, For example, when it exceeds 10 μm, the magnetic properties of the oxides of M and M in the thickness of the mixed layer 14 are inferior to Fe, resulting in an excessive decrease in the overall magnetic properties. Microscopically, the mixed layer 14 can include a plurality of granular protrusion structures.

Another embodiment of the present disclosure provides a magnetic material 2, as shown in FIG. 2, comprising: a core body 20; a first passivation layer 22 on the surface of the core body 20; and a second passivation layer 24 located at the The surface of a passivation layer 22. The particle diameter of the magnetic material 2 may be, for example, 0.5 to 50 μm or 50 to 110 μm.

The core body 20 contains 99% by weight or more of Fe, based on the total weight of the core body 20. In an embodiment, the core body 20 comprises only the metallic element Fe, ie 100% by weight of Fe. In another embodiment, the core body 20 may comprise an oxide of Fe and Fe, wherein the oxide of Fe may include ferrous oxide (FeO), ferric oxide (Fe ₂ O ₃ ), and triiron tetroxide (Fe). ₃ O ₄ ), or a combination of the foregoing. In this embodiment, the content of Fe may be 99 wt% or more, for example, 99 wt%, 99.95 wt%, or 99.99 wt%, and the content of Fe oxide may be 1 wt% or less, for example, 0.01 wt%, 0.05 wt. %, or 1 wt%, based on the total weight of the core body 20.

The first passivation layer 22 may comprise an oxide of a FeM alloy, where M is Cr, Si, Al, Ti, Zr, or a combination of the foregoing. The content of M in the first passivation layer 22 may be 5 to 80 wt%, based on the total weight of the oxide of the FeM alloy. If the content of M is too low, for example, less than 5% by weight, the core body is liable to form oxides, resulting in a decrease in overall magnetic properties; if the content of M is too low, for example, more than 80% by weight, the magnetic properties of M are worse than Fe. This causes the overall magnetic properties to drop too much. The first passivation layer 22 may have a thickness of 0.05 to 10 μm, for example, 0.1 μm, 0.3 μm, 1.5 μm, 3 μm, or 5 μm.

The second passivation layer 24 can include an oxide of M, where M is Cr, Si, Al, Ti, Zr, or a combination of the foregoing. The thickness of the second passivation layer 24 ranges from 0.05 to 10 μm, for example, 0.1 μm, 0.3 μm, 1.5 μm, 3 μm, or 5 μm. If the second passivation layer 24 is too thin, for example, less than 0.05 μm, when the magnetic material is co-fired with silver, the silver easily diffuses into the formation of an electrical path, causing the magnetic element to fail; if the thickness of the second passivation layer 24 is too thick, For example, when it exceeds 10 μm, the magnetic properties of the oxides of M and M in the second passivation layer 24 are inferior to Fe, resulting in an excessive decrease in the overall magnetic properties. Microscopically, the second passivation layer 24 can include a plurality of granular protrusion structures.

3A-3C are schematic views showing an intermediate process for manufacturing magnetic materials 3, 4 according to an embodiment of the present disclosure. Hereinafter, the manufacturing process of the magnetic materials 3, 4 of the present disclosure will be described according to an embodiment. However, the description of this embodiment is for illustrative purposes only, and the method of manufacturing the magnetic particles is not limited to this embodiment.

First, the second particles 200 as an outer layer material are ground fine, for example, 0.02 to 10 μm. Thereafter, the ground second particles 200 are dry-ball-mixed with the first particles 100 as a core body, and the second particles 200 are uniformly coated on the surface of the first particles 100 as shown in FIG. 3A. The second particles 200 may have voids between each other that do not completely cover the surface of the first particles 100. The first particles 100 and the second particles 200 may also be mixed by other suitable physical methods, such as shear agitation mixing, high speed agitation mixing, and the like. The chemical method may also coat the second particles 200 on the surface of the first particles 100. However, it is necessary to add an additional cleaning step, which may cause problems of solvent residue and easy oxidation of the material.

The first particles 100 may be Fe, Fe oxide or a combination thereof, such as ferrous oxide (FeO), ferric oxide (Fe ₂ O ₃ ), triiron tetroxide (Fe ₃ O ₄ ), or the foregoing The combination. When the first particles 100 are Fe, the particle diameter thereof may be 0.5 to 100 μm. When the first particles 100 are oxides of Fe, the particle diameter thereof may be 0.5 to 100 μm. The second particle 200 may be an oxide or hydroxide of M, wherein M is Cr, Si, CrSi, CrSiFe, Al, FeCr, FeSi, FeAl, Ti, Zr, or a combination thereof. The particle diameter of the second particles 200 may be 0.02 to 10 μm. The weight ratio when the first particles 100 are mixed with the second particles 200 may be 200:1 to 5:1.

Next, the mixture of the first particles 100 and the second particles 200 described above is placed in a hydrogen atmosphere of about 5%, and reacted at about 600 to 1200 ° C for about 2 to 15 hours to form a magnetic material 3.

During the hydrogenation process, part of the second particles 200 undergo a reduction reaction to reduce the oxide of M to the metal element M. The metal element M diffuses into the first particle 100 and forms an alloy with the composition of the first particle 100, for example, an FeM alloy, and further forms an alloy layer 32 on the surface of the first particle 100. The thickness of the alloy layer 32 may be 0.05 to 10 μm depending on the time of the hydrogenation reaction. The hydrogenation reaction time may be 2 to 15 hours. If the hydrogenation reaction time is too short, the formed alloy layer 32 is too thin, resulting in failure to oxidize to form a passivation layer after subsequent sintering, and the core body 30 is easily oxidized to cause a decrease in magnetic properties. The remaining metal element M that is not diffused into the first particle 100 or the oxide of the unreduced M will remain on the surface of the alloy layer 32, referred to herein as the mixed layer 34. The portion inside the alloy layer 32 is referred to as the core body 30. In the embodiment in which the first particles 100 are oxides of Fe or Fe, the oxides of Fe are almost always reduced to Fe after the hydrogenation reaction, so that the core body 30 has Fe as a main component, so that it has a pure metal. Good magnetic properties.

Therefore, the magnetic material 3 produced after the hydrogenation reduction reaction includes the core main body 30 mainly composed of Fe (99 wt% or more), the alloy layer 32 on the surface of the core main body 30, and the mixed layer 34 on the surface of the alloy layer 32. As shown in Figure 3B.

It should be noted that the magnetic material of the present disclosure, through the above hydrogenation reduction reaction, comprises only a thin alloy layer on the surface of the core body, compared to the magnetic material in which the alloy is used as the entire core body in order to insulate the core body from the outside. It can achieve the purpose of making the core body less susceptible to oxidation and causing a decrease in magnetic properties, and can be co-fired with silver at 450-900 °C. In addition, since the inner core body is protected by the above-mentioned thin alloy layer, the present disclosure uses Fe or Fe and a very small amount of Fe oxide (about 1 wt% or less) as a core body, so the magnetic properties of the whole core body are compared with the alloy. Materials, the present disclosure greatly enhances magnetic properties such as overall saturation magnetization.

Next, the magnetic material 3 is placed in an air atmosphere and sintered at about 450 to 900 ° C for about 1 to 5 hours to form a magnetic material 4 .

Through the above sintering process, the alloy in the alloy layer 32 is further oxidized to form an oxide of the alloy to form the first passivation layer 42, and the metal element M in the mixed layer 34 is further oxidized to form an oxide of M to form the second passivation layer 44. Therefore, the magnetic material 4 produced after sintering includes the core body 40, the first passivation layer 42 on the surface of the core body 40, and the second passivation layer 44 on the surface of the first passivation layer 42. Further, after sintering, the magnetic materials 4 are bonded to each other through the second passivation layer 44 to form an aggregate of the magnetic material 4 as shown in FIG. 3C. However, it should be understood that although FIG. 3C only depicts an aggregate of two magnetic materials 4, in some embodiments, the magnetic material 4 may exist in an aggregate form of more magnetic materials 4. Alternatively, in other embodiments, the magnetic materials 4 are not bonded together, but are present in a monomeric form, as shown in FIG.

A further embodiment of the present disclosure provides a magnetic component comprising a magnetic material and a sinter of a metal. The magnetic material may be the aforementioned magnetic material 1 or magnetic material 2. The metal used may include: silver, copper, or an alloy of the foregoing. In the sinter, the magnetic material may be a magnetic material 1 or a powder monomer of the magnetic material 2, a fragment of the powder monomer, an aggregate of the powder monomer, or a combination thereof.

In one embodiment, silver may be co-sintered with magnetic material 1 or magnetic material 2, and the sintering temperature may be 450 to 900 °C. In this case, since the self-generated passivation layer is formed, it is not necessary to add an organic substance as an insulating material, and when an organic substance is used as an insulating layer, the insulating layer loses the insulating effect (forms carbon or carbon dioxide gas) after being subjected to a high temperature, causing the magnetic material to fail. . However, the temperature at which the magnetic material is co-sintered with the metal can be adjusted according to the oxide property of the outer layer of the magnetic material or the melting point of the different metal materials, and the passivation layer between the magnetic material and the metal is demanded.

The magnetic component may include a laminated inductor, a wound inductor, or an Electromagnetic Interference (EMI) suppression component. However, the magnetic element described in the present disclosure is not limited thereto. In addition, the manufacturing methods vary depending on the type of magnetic component. Taking a laminated inductor as an example, the magnetic material 1 or the magnetic material 2 may be uniformly mixed with the slurry and then coated to form a film. Next, the metal wiring is printed on the film by a method such as screen printing. Then, the film is placed in an air atmosphere, and co-sintered at about 450 to 900 ° C for about 0.5 to 10 hours to form a laminated inductor. Similarly, the magnetic material 1 or the magnetic material 2 can also be applied to other types of magnetic elements. In view of the fact that various magnetic element manufacturing methods are well known to those of ordinary skill in the art, they can be used by those of ordinary skill in the art. Modification and application, so I will not repeat them here.

The magnetic material provided by the present disclosure uses Fe or Fe and a very small amount of Fe oxide (about 1 wt% or less) as a core body, and only penetrates the thin alloy layer and the thin passivation layer outside the core body to insulate the core body from the outside. The purpose is to substantially improve the magnetic properties such as the overall saturation magnetization compared to the magnetic material in which the alloy is used as the entire core body. Therefore, the magnetic material provided by the present disclosure has a high magnetic permeability, a high saturation magnetization amount, and can be co-fired with a metal to produce a self-generated passivation layer to form an active magnetic element. In addition, the magnetic element formed by the magnetic material provided by the present disclosure also has advantages of high magnetic permeability and high saturation magnetization.

The magnetic materials and characteristics thereof provided by the present disclosure are illustrated by the following examples and comparative examples:

Comparative Example 1 / Example 1

Comparative Example 1 and Example 1 were prepared in accordance with the contents shown in Table 1. Except for Comparative Example 1-1, both the first particles and the second particles were mixed by dry ball milling, and the resulting mixture was further subjected to a process shown in Table 1 to form a magnetic material.

The magnetic permeability of each of the particles of Comparative Examples 1-1 to 1-5 and Examples 1-1 to 1-8 was measured, and the results are shown in Table 2. .

Comparative Example 2 / Example 2

Comparative Example 2 and Example 2 were prepared in accordance with the contents shown in Table 3. Except for Comparative Example 2-1, both the first particles and the second particles were mixed by dry ball milling, and the resulting mixture was further subjected to a process shown in Table 3 to form a magnetic material.

The results of measuring the magnetic permeability of each of the particles of Comparative Examples 2-1 to 2-2 and Examples 2-1 to 2-8 are shown in Table 4.

Referring to Tables 2 and 4, it was found from the results of Comparative Examples 1-1 and 2-1 that although the metal Fe originally had a good magnetic permeability, the above properties were remarkably deteriorated after the sintering process. Similarly, from the results of Comparative Examples 1-2 and 2-2, it was also found that although the mixture of the first particles Fe and the second particles Cr ₂ O ₃ originally had a good magnetic permeability, after the sintering process, the above properties were also Significantly worse. From Comparative Example 1-3, it was found that the ferromagnetic permeability was poor by using ferric oxide (Fe ₂ O ₃ ) as the first particle and Cr ₂ O ₃ as the second particle mixture.

From the above, it can be seen that although the metal Fe is the first particles (such as Comparative Examples 1-1 and 1-2), after the sintering process (such as Comparative Examples 2-1 and 2-2), the good magnetic permeability of the original metal Fe will be Greatly affected. Further, ferric oxide (Fe ₂ O ₃ ) was used as the first particles (e.g., Comparative Examples 1-3), and did not have good magnetic permeability.

However, referring to Table 2, the results of Comparative Examples 1-1 to 1-8 and Comparative Example 1-1 revealed that the first particles (Fe, Fe ₂ O ₃ ) and the different second particles (Cr ₂ O _{3 )} The mixture of Al(OH) ₃ , SiO ₂ , Fe ₂ O ₃ ) was ball milled, and after the hydrogenation reaction, the magnetic permeability (@ 10 MHz) was significantly improved compared with Comparative Example 1-1. Further, the results of Comparative Examples 1-1 to 1-8 and Comparative Examples 1-4 and 1-5 were found to be found in comparison with Comparative Examples 1-4 in which Fe alloys (FeSi, FeNiMo) were the first particles, 1-5. The magnetic particles obtained in Examples 1-1 to 1-5 were excellent in magnetic permeability (@1 MHz, @10 MHz). It is worth mentioning that although Example 1-5 uses Fe ₂ O ₃ as the first particle, after the hydrogenation reaction, the magnetic permeability (@ 1 MHz, @ 10 MHz) is greatly improved compared with Comparative Example 1-3. .

Fig. 4 shows the magnetic permeability of the magnetic materials of Comparative Example 1-1 and Examples 1-1 and 1-5. It can be seen that the magnetic permeability of the examples 1-1 and 1-5 is improved at a high frequency (for example, 1 MHz to 100 MHz) compared with the comparative example 1-1.

Next, referring to Table 4, it can be found by comparing the results of Examples 2-1 to 2-8 with Comparative Example 2-1 that the first particles (Fe, Fe ₂ O ₃ ) and the different second particles (Cr ₂ O _{3 )} , Al(OH) ₃ , SiO ₂ , Fe ₂ O ₃ ), the mixture after ball milling, in the case of hydrogenation reaction before the sintering process, the magnetic permeability (@ 1 MHz, @ 10 MHz) compared to Comparative Example 2 -1 has a significant improvement. Further, the results of Comparative Examples 2-1 to 2-8 and Comparative Example 2-2 revealed that the first particles (Fe, Fe ₂ O ₃ ) and the different second particles (Cr ₂ O ₃ , Al (OH) ₃ ) SiO ₂ , Fe ₂ O ₃ ) The mixture after ball milling is subjected to a hydrogenation reaction before the sintering process, and the magnetic permeability (@ 1 MHz) is also significantly higher than that of Comparative Example 2-2. Upgrade.

Fig. 5 shows the magnetic permeability of the magnetic materials of Comparative Examples 2-1 and 2-2 and Examples 2-1 and 2-5. It can be seen that the magnetic permeability of the examples 2-1 and 2-5 is improved at a high frequency (for example, 1 MHz to 100 MHz) compared with the comparative examples 2-1 and 2-2.

Scanning electron microscope (SEM) observation

Fig. 6A is a scanning electron microscope (SEM) sectional view showing the magnetic material obtained in Example 2-1. It can be seen that there is an alloy region uniformly distributed around the core of the main body. Fig. 6B is an enlarged view of the region indicated by the square in Fig. 6A, wherein the first region is Fe, the second region is a passivation layer containing FeCr oxide, and the third region is included. Passivation layer of Cr oxide (Cr ₂ O ₃ ).

Component Analysis (EDS-Line Scan) results

Fig. 7A is a scanning electron microscope (SEM) sectional view showing the magnetic material obtained in Example 2-1. Fig. 7B is an enlarged view of a region indicated by a square in Fig. 7A. After performing the component analysis (EDS-Line Scan) on the area shown in Fig. 7B, it was found that the content of Fe in the first region close to the center was the highest, and only a small amount of Cr and O elements were contained, which confirmed that the magnetic material center of the present disclosure was almost It consists only of Fe. Further, it can also be seen that the content of the Cr element decreases from the third region toward the center, confirming that the Cr element in the magnetic material has indeed diffused from the third region to the second region. Judging from the content of the O element, it is presumed that the second region includes an oxide of FeCr, and the third region includes an oxide of Cr. In addition, the Fe content of the third region shown in Fig. 7B may be caused by an error in the detection position during the component analysis. Theoretically, only a small amount of Fe diffuses from the first region near the center during the heat treatment to Zone II and Zone III.

Comparative example 3

The magnetic material prepared in Comparative Example 1-1 was co-fired with silver at a sintering temperature of 600 ° C to form a co-fired inductor (forming conditions: ψ 9 mm × ψ 5 mm mold, and the temperature was continued to 600 ° C and sintering was continued for 1 hr. Finally naturally cooled). Fig. 8A shows an SEM image of Comparative Example 3. It can be seen from Fig. 8A that no self-generated passivation layer is formed.

Example 3-1

The magnetic material obtained in Example 1-6 was co-fired with silver at a sintering temperature of 600 ° C to form a co-fired inductor (forming conditions: ψ 9 mm × ψ 5 mm mold, and the temperature was continued to 600 ° C and sintering was continued for 1 hr. Finally naturally cooled). Fig. 8B shows an SEM image of Example 3-1. The formation of the self-generated passivation layer (indicated by the arrow) can be seen from Fig. 8B.

Example 3-2

The magnetic materials prepared in Examples 1-8 were co-fired with silver at a sintering temperature of 600 ° C to form a co-fired inductor (forming conditions: ψ 9 mm × ψ 5 mm mold, and the temperature was continued to 600 ° C and sintering was continued for 1 hr. Finally naturally cooled). Figure 8C shows an SEM image of Example 3-2. The formation of the autogenous passivation layer (pointed by the arrow) can be seen from Fig. 8C.

The above results confirm that the magnetic particles provided by the present disclosure form a self-generated passivation layer with a metal (for example, silver) to insulate the magnetic particles from the metal, and successfully form an effective inductor.

The present disclosure has been disclosed in the above-described preferred embodiments, and is not intended to limit the disclosure. Any one of ordinary skill in the art can make any changes without departing from the spirit and scope of the disclosure. And the scope of protection of this disclosure is subject to the definition of the scope of the patent application.

Claims (16)

 A magnetic material comprising: a core body comprising 99% by weight or more of Fe, based on the total weight of the core body; an alloy layer on the surface of the core body, including FeM alloy, wherein M is Cr, Si, Al, Ti, Zr, or a combination thereof; and a mixed layer on the surface of the alloy layer, including oxides of M and M.   The magnetic material according to claim 1, wherein the Fe oxide comprises: ferrous oxide (FeO), ferric oxide (Fe ₂ O ₃ ), triiron tetroxide (Fe ₃ O ₄ ), Or a combination of the foregoing.  The magnetic material according to claim 1, wherein the magnetic material has a particle diameter of 0.5 to 110 μm.    The magnetic material according to claim 1, wherein the content of M in the alloy layer is 5 to 80% by weight based on the total weight of the FeM alloy.    The magnetic material according to claim 1, wherein the alloy layer has a thickness of 0.05 to 10 μm.    The magnetic material according to claim 1, wherein the mixed layer has a thickness of 0.05 to 10 μm.    A magnetic material comprising: a core body comprising 99 wt% or more of Fe, based on the total weight of the core body; a first passivation layer on the surface of the core body, comprising an oxide of a FeM alloy, wherein M Is a combination of Cr, Si, Al, Ti, Zr, or a combination thereof; and a second passivation layer on the surface of the first oxide layer, including an oxide of M.   The magnetic material according to claim 7, wherein the Fe oxide comprises: ferrous oxide (FeO), ferric oxide (Fe ₂ O ₃ ), triiron tetroxide (Fe ₃ O ₄ ), Or a combination of the foregoing.  The magnetic material according to claim 7, wherein the magnetic material has a particle diameter of 0.5 to 110 μm.    The magnetic material according to claim 7, wherein the content of M in the first passivation layer is 5 to 80% by weight based on the total weight of the oxide of the FeM alloy.    The magnetic material according to claim 7, wherein the first passivation layer has a thickness of 0.05 to 10 μm.    The magnetic material according to claim 7, wherein the second passivation layer has a thickness of 0.05 to 10 μm.    A magnetic element comprising a magnetic material and a sinter of a metal, wherein the magnetic material comprises the magnetic material of any one of claims 1 to 12.    The magnetic component of claim 13, wherein the magnetic component comprises: a laminated inductor, a wound inductor, or an electromagnetic interference (EMI) suppression component.    The magnetic component of claim 13, wherein the metal comprises: silver, copper, or an alloy of the foregoing.    The magnetic component according to claim 13, wherein the magnetic material in the sintered body is a powder monomer, a fragment of the powder monomer, an aggregate of the powder monomer, or a combination thereof .