High saturation high resistance magnetic powder core and manufacturing method thereof, inductor

Abstract

This invention discloses a high-saturation, high-resistivity magnetic powder core and its manufacturing method, as well as an inductor. The high-saturation, high-resistivity magnetic powder core includes a core portion and a permeation portion, with the permeation portion covering the core portion. The resistivity of the core portion differs from that of the permeation portion, and the saturation magnetization of the core portion differs from that of the permeation portion. The high-saturation, high-resistivity magnetic powder core proposed in this invention solves the technical problem that existing high-saturation, high-resistivity magnetic powder cores cannot simultaneously achieve high saturation magnetization and high resistivity. Furthermore, when using this magnetic powder core to manufacture inductor devices, the inductor devices can meet the requirements of high-frequency, high-current operating environments.

Description

Technical Field

[0001] This invention relates to the technical field of electronic components, and in particular to a high-saturation, high-resistivity magnetic powder core and its manufacturing method, as well as an inductor. Background Technology

[0002] Strategic emerging fields such as new energy and next-generation mobile communications are placing higher demands on electronic components. High power density, high frequency, high efficiency, high cost-effectiveness, and miniaturization have become the main directions for power inductor research and development. High power density and high frequency require the magnetic powder core to possess both high saturation magnetization and high resistivity. However, for uniform magnetic powder cores, there is a trade-off between high saturation magnetization and high resistivity, making it difficult to achieve both simultaneously. Summary of the Invention

[0003] The purpose of this invention is to solve the technical problem that existing high-saturation, high-resistivity magnetic powder cores cannot simultaneously achieve high saturation magnetization and high resistivity, and to propose a high-saturation, high-resistivity magnetic powder core, its manufacturing method, and an inductor.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A high-saturation, high-resistivity magnetic powder core includes a core and a permeation section, wherein the permeation section covers the core, the resistivity of the core is different from that of the permeation section, and the saturation magnetization of the core is different from that of the permeation section.

[0006] In some embodiments of the present invention, the resistivity of the core is less than the resistivity of the permeation portion.

[0007] In some embodiments of the present invention, the saturation magnetization of the core is greater than that of the permeation portion.

[0008] In some embodiments of the present invention, the thickness of the permeation portion is 10 to 300 micrometers.

[0009] In some embodiments of the present invention, the elements and contents in the permeation section are: Fe 81-96 wt%, Si 2-11 wt%, and also include at least one of Al, Cr, B, C, and O.

[0010] In some embodiments of the present invention, when the permeation section contains Al, the Al content is 0.5–8 wt%; when the permeation section contains Cr, the Cr content is 0.5–8 wt%; when the permeation section contains B, the B content is 0.5–8 wt%; when the permeation section contains C, the C content is 0.5–8 wt%; and when the permeation section contains O, the O content is 0.5–5 wt%.

[0011] In some embodiments of the present invention, the elements and their contents in the core are: Fe 83-97 wt%, Si 1-9 wt%, and also include at least one of Al, Cr, B, C, and O.

[0012] In some embodiments of the present invention, when the core contains Al, the Al content is 0.5–8 wt%; when the core contains Cr, the Cr content is 0.5–8 wt%; when the core contains B, the B content is 0.5–8 wt%; when the core contains C, the C content is 0.5–8 wt%; and when the core contains O, the O content is 0.3–2 wt%.

[0013] In some embodiments of the present invention, a surface coating is also included, the surface coating being located on the outermost layer and covering the permeation portion.

[0014] This invention also proposes a method for manufacturing a high-saturation, high-resistivity magnetic powder core, used to manufacture the high-saturation, high-resistivity magnetic powder core as described in any of the preceding claims, characterized by comprising the following steps: S1: obtaining the core of the high-saturation, high-resistivity magnetic powder core by powder coating, granulation, pressing, and sintering; S2: coating the surface of the core with insulating particles using a coating-diffusion heat treatment or vacuum impregnation method, and allowing them to penetrate into the surface layer of the core, to obtain the high-saturation, high-resistivity magnetic powder core with the penetrating portion covering the core.

[0015] The present invention also proposes an inductor comprising a high-saturation, high-resistivity magnetic powder core and a coil as described in any of the preceding claims, the coil being wound around the surface of the high-saturation, high-resistivity magnetic powder core.

[0016] The present invention has the following beneficial effects:

[0017] The high-saturation, high-resistivity magnetic powder core proposed in this invention comprises a core and a permeation layer. By utilizing the permeation layer to encapsulate the core, and because the resistivity of the core differs from that of the permeation layer, as does the saturation magnetization of the core, the magnetic powder core can simultaneously achieve different resistivities and different saturation magnetizations. Experimental data shows that the magnetic powder core in this invention exhibits improved permeability and high DC bias capability compared to existing technologies, while reducing volumetric power loss. This solves the technical problem of existing high-saturation, high-resistivity magnetic powder cores failing to simultaneously achieve high saturation magnetization and high resistivity. When using this magnetic powder core to manufacture inductor devices, the inductor device can meet the requirements of high-frequency, high-current operating environments.

[0018] In addition, some embodiments also have the following beneficial effects:

[0019] By making the resistivity of the core smaller than that of the penetrating part, and the saturation magnetization of the core greater than that of the penetrating part, the penetrating part of the magnetic powder core can have high resistivity and the core can have high saturation magnetization. When using this magnetic powder core to manufacture a wire-wound inductor, eddy current losses are concentrated in the penetrating part of the magnetic powder core, which requires a high resistivity. For the core of the magnetic powder core, eddy current losses are small, and a high resistivity is not required, but a high saturation magnetization can be provided. Thus, the wire-wound inductor with this magnetic powder core can simultaneously achieve both high saturation magnetization and high resistivity.

[0020] Other beneficial effects of the embodiments of the present invention will be further described below. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the high-saturation, high-resistivity magnetic powder core in an embodiment of the present invention;

[0022] Figure 2 This is a schematic cross-sectional view of a high-saturation, high-resistivity magnetic powder core in an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the inductor structure in an embodiment of the present invention;

[0024] Figure 4 This is a flowchart of the steps for fabricating a high-saturation, high-resistivity magnetic powder core in an embodiment of the present invention;

[0025] Figure 5 This is a flowchart illustrating the steps involved in manufacturing an inductor according to an embodiment of the present invention;

[0026] The attached figures are labeled as follows:

[0027] 100 is a high-saturation, high-resistivity magnetic powder core, 200 is a coil, and 300 is an inductor;

[0028] 110 is the core, 120 is the penetration part, and 130 is the surface coating. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0030] It should be noted that the directional terms such as left, right, up, down, top, and bottom in this embodiment are only relative concepts or are based on the normal use of the product, and should not be considered as restrictive.

[0031] The terminology mentioned in the embodiments of this invention is as follows:

[0032] Magnetic powder core: Magnetic powder core is a soft magnetic material made by mixing and pressing ferromagnetic powder particles with an insulating medium.

[0033] Power inductors: Power inductors are inductors that can carry large currents. They are used in switching power supplies and act as energy transfer stations. Currently, the most common type of power inductor is the wire-wound inductor, which is an inductor device made by winding a coil around a soft magnetic core.

[0034] To simultaneously improve the saturation magnetization and resistivity of the magnetic powder core, thereby enhancing the DC bias performance and high-frequency loss characteristics of the power inductor, the high saturation magnetization and high resistivity of the material translate into high DC bias capability and low loss in the device. Increasing the strength of the magnetic powder core improves the mechanical properties and yield of the device.

[0035] The following embodiments of the present invention provide a high-saturation, high-resistivity magnetic powder core 100, such as... Figure 1 and Figure 2 As shown, it includes a core 110 and a permeation portion 120. The permeation portion 120 covers the core 110. The resistivity of the core 110 is different from that of the permeation portion 120, and the saturation magnetization of the core 110 is different from that of the permeation portion 120.

[0036] In this embodiment of the invention, the thickness of the permeation portion 120 is 10 to 300 micrometers.

[0037] In other embodiments, the resistivity of the core 110 is less than that of the penetrating portion 120, and / or the saturation magnetization of the core 110 is greater than that of the penetrating portion 120. For wire-wound inductors, eddy current losses are concentrated on the outer surface of the magnetic powder core, therefore the surface of the magnetic powder core requires a high resistivity. For the core of the magnetic powder core, eddy current losses are small, and a high resistivity is not required, but a high saturation magnetization can be provided. Using a surface coating-penetration method, insulating particles are coated onto the surface of the magnetic powder core, and the insulating particles are penetrated into the surface of the magnetic powder core using high-temperature diffusion heat treatment or vacuum impregnation methods, so that a high-resistivity penetrating portion is formed on the surface of the magnetic powder core without changing the structure of the core. Using this method, a magnetic powder core with high surface resistivity and high saturation magnetization can be prepared.

[0038] The elements and their contents in the permeation section 120 are: Fe 81-96 wt%, Si 2-11 wt%, and at least one of Al, Cr, B, C, and O. The raw materials used to manufacture the permeation section 120 are nano-SiO2, Al2O3, MgO, ZnO, Cr2O3, etc.

[0039] When the permeation section contains Al, the Al content is 0.5–8 wt%.

[0040] When the permeation section contains Cr, the Cr content is 0.5–8 wt%.

[0041] When the permeation section contains B, the content of B is 0.5-8 wt%.

[0042] When the permeation section contains C, the C content is 0.5–8 wt%.

[0043] When the permeation section contains O, the O content is 0.5–5 wt%.

[0044] The elements and their contents in the core 110 are: 83-97 wt% Fe, 1-9 wt% Si, and at least one of Al, Cr, B, C, and O. The raw material used to make the core 110 is a composite material made of FeSi-based alloy magnetic powder and 0.5-5 wt% epoxy resin, phenolic resin, or silicone resin.

[0045] When the core contains Al, the Al content is 0.5–8 wt%.

[0046] When the core contains Cr, the Cr content is 0.5–8 wt%.

[0047] When the core contains B, the content of B is 0.5-8 wt%.

[0048] When the core contains C, the C content is 0.5–8 wt%.

[0049] When the core contains oxygen, the oxygen content is 0.3–2 wt%.

[0050] In this embodiment of the invention, a surface coating 130 may also be included, which is located as the outermost layer and covers the permeation portion 120. The surface coating 130 has a thickness of approximately 1.5 mm and is composed of epoxy resin.

[0051] This invention also proposes a method for manufacturing a high-saturation, high-resistivity magnetic powder core 100, used to manufacture the high-saturation, high-resistivity magnetic powder core 100 described in any of the above embodiments. (See reference...) Figure 4 It includes the following steps:

[0052] S1: Core forming and sintering of magnetic powder core 110: The core 110 of high-saturation, high-resistivity magnetic powder core 100 is obtained by powder coating, granulation, pressing, and sintering. The specific parameters are as follows:

[0053] (1) Powder coating: Add 0.1% to 2% phosphoric acid by weight of powder, add 10% to 25% anhydrous ethanol or acetone, stir for 10 to 60 minutes, and dry at 70 to 150°C for 1 hour;

[0054] (2) Granulation: Add 0.5% to 5% of epoxy resin, phenolic resin or organosilicon resin by weight of powder, add 10% to 25% of anhydrous ethanol or acetone, stir for 10 to 60 minutes and then air dry naturally.

[0055] (3) Pressing: At room temperature, the pressure is 1200-2400MPa, and the pressure is held for 1-15s;

[0056] (4) Sintering: Hold at 350-800℃ for 30-240 minutes.

[0057] S2: Preparation of the penetrating part 120: Insulating particles (such as nano-SiO2, Al2O3, MgO, ZnO, Cr2O3, etc.) are coated onto the surface of the core using a coating-diffusion heat treatment or vacuum impregnation method, and are allowed to penetrate into the surface layer of the core 110 of the high-saturation high-resistivity magnetic powder core. The thickness of the penetrating part is 10 to 300 micrometers, so as to obtain the high-saturation high-resistivity magnetic powder core 100 with the penetrating part 120 covering the core 110. The specific parameters are as follows:

[0058] (1) Coating-diffusion heat treatment: The above oxide suspension is sprayed onto the magnetic powder core green body using a spraying method, ensuring that the content of the sprayed oxide accounts for 0.5% to 5% of the mass ratio of the magnetic powder core. The diffusion heat treatment temperature is 350 to 800℃, and the holding time is 30 to 240 min. The penetration thickness is controlled by controlling the diffusion heat treatment temperature and time.

[0059] (2) Vacuum impregnation: The impregnation solution is a suspension composed of epoxy resin or phenolic resin solution and the above-mentioned oxides. The vacuum degree is below 10⁻¹ Pa, and the impregnation time is 30–360 min, followed by drying at 80°C for 30–120 min.

[0060] In a specific embodiment, since the magnetic powder core 110 is first fabricated, and then a permeation layer is fabricated in the magnetic powder core 110 using a fabrication method, a continuous transition layer exists between the core and the permeation layer of the fabricated magnetic powder core. Taking the permeation of SiO2 and Al2O3 as an example, the Si, Al, and O content of the magnetic powder core is a stable value. When a continuous increase in the composition of these elements is detected on the surface, it can be considered as the region of the permeation layer.

[0061] In this embodiment of the invention, step S3 is also included: spraying: an upper surface coating 130 is sprayed onto the high-saturation, high-resistivity magnetic powder core 100 containing the core 110 and the permeation part 120. The surface coating 130 can also be called a corrosion-resistant layer, such as epoxy resin, or it can be chloroprene rubber, chlorinated vinylene copolymer, chlorinated polyether, polytetrafluoroethylene, and polyvinyl chloride, etc.

[0062] This invention also proposes an inductor 300, comprising a high-saturation, high-resistivity magnetic powder core 100 and a coil 200 as described in any of the preceding embodiments, wherein the coil 200 is wound around the surface of the high-saturation, high-resistivity magnetic powder core 100. For example... Figure 3 and Figure 5 As shown, after steps S2 / S3 above, step S4 is performed: winding: a coil 200 is wound on the high-saturation, high-resistivity magnetic powder core 100 to obtain the inductor 300.

[0063] In summary, the embodiments of the present invention have the following advantages:

[0064] 1. High-saturation, high-resistivity magnetic powder cores can be fabricated, enabling their inductor devices to meet the requirements of high-frequency (50kHz~3MHz) and high-current (0.5~30A) operating environments.

[0065] 2. It can improve the strength of magnetic powder cores and their inductive devices, ensuring the yield rate of products.

[0066] 3. The preparation method of the permeation section is energy-efficient, environmentally friendly, low-cost, simple, highly automated, and easy to industrialize.

[0067] Example 1:

[0068] The primary application scenario achieved using the basic solution. In this embodiment, there may be individual optimizations to the basic solution to ensure it can smoothly support this embodiment.

[0069] This embodiment provides a high-saturation, high-resistivity magnetic powder core and its device. The inductor described above is also referred to as a device or inductor device in this and other embodiments. See also... Figure 2 and Figure 3 The magnetic powder core comprises a magnetic powder core body and a surface coating. The surface coating has a thickness of 1.5 mm and is composed of epoxy resin. The magnetic powder core body comprises a permeation layer and a core. In this embodiment, the mass percentages of Fe, Si, Al, C, and O in the core of the magnetic powder core are Fe: 84.0%, Si: 8.8%, Al: 5.0%, C: 0.9%, and O: 1.3%, respectively. The raw material for making the core is Fe. 85 A composite material made of Si9Al6 magnetic powder and epoxy resin. The mass percentages of Fe, Si, Al, C, and O in the permeated portion of the magnetic powder core are Fe: 81.2%, Si: 9.5%, Al: 5.5%, C: 0.9%, and O: 2.9%, respectively, with a thickness of 200–250 micrometers. The fabrication process involves... 85The core is a composite material (si9Al6 magnetic powder + epoxy resin) infiltrated with SiO2. The device is a wire-wound inductor, comprising a magnetic powder core and an enameled coil (preferably an enameled coil in this embodiment and the following embodiments). The enameled coil is copper wire coated with insulating varnish, with a circular or rectangular cross-section and a diameter of 0.3–2 mm. Table 1 shows the test results of the effective permeability at 100 kHz, volumetric power loss at 100 kHz and 100 mT, and DC bias capability at 100 Oe for Example 1 and Comparative Example 1. Compared with Comparative Example 1, the solution in Example 1 has significant advantages.

[0070] In this embodiment, the number of turns is customized and determines the final inductance. The coil is wound evenly on the magnetic powder core. The number of turns is determined based on application requirements and the size of the magnetic powder core.

[0071] Comparative Example 1

[0072] This comparative example provides a magnetic powder core and its device. The magnetic powder core body does not contain a permeation portion, and the device is a wire-wound inductor. Other structures and preparation methods are the same as in Example 1, so they will not be described again.

[0073] Example 2

[0074] This embodiment provides a high-saturation, high-resistivity magnetic powder core and its device. The magnetic powder core comprises a core body and a surface coating. The surface coating is the same as that in Embodiment 1. The core body comprises a permeated portion and a core portion. The mass percentages of Fe, Si, C, and O in the core portion of the magnetic powder core are Fe: 91.7%, Si: 4.6%, C: 1.3%, and O: 2.4%, respectively. In this embodiment, the raw material for the core portion is Fe. 96.5 Si 3.5 A composite material made of magnetic powder and epoxy resin. The mass percentages of Fe, Si, C, and O in the permeated part of the magnetic powder core are Fe: 88.8%, Si: 6.3%, C: 1.6%, and O: 3.3%, respectively. In this embodiment, the permeated part is fabricated by... 96.5 Si 3.5 The composite material made of magnetic powder and epoxy resin (i.e., the core) is infiltrated with SiO2, and the thickness of the infiltrated part is 200-250 micrometers. The above device is a wire-wound inductor, which includes a magnetic powder core and an enameled coil. The enameled coil is a copper wire coated with insulating varnish, with a circular or rectangular cross-section. The effective permeability at 100 kHz, the volumetric power loss at 100 kHz and 100 mT, and the DC bias capability at 100 Oe of Example 2 and Comparative Example 2 are shown in Table 1. Compared with Comparative Example 2, the scheme of Example 2 has obvious advantages.

[0075] Comparative Example 2

[0076] This comparative example provides a magnetic powder core and its device. The magnetic powder core body does not contain a permeation portion, and the device is a wire-wound inductor. Other structures and preparation methods are the same as in Example 2, so they will not be described again.

[0077] Example 3

[0078] This embodiment provides a high-saturation, high-resistivity magnetic powder core and its device. The magnetic powder core comprises a magnetic powder core body and a surface coating. The surface coating is the same as that in Embodiment 1. The magnetic powder core body comprises a permeation section and a core. In this embodiment, the raw material for the core is a composite material made of Fe96.5Si3.5 magnetic powder and epoxy resin. The mass percentages of Fe, Si, C, and O in the core of the magnetic powder core are Fe: 91.7%, Si: 4.6%, C: 1.3%, and O: 2.4%, respectively. The mass percentages of Fe, Si, C, and O in the permeation section of the magnetic powder core are Fe: 88.8%, Si: 6.3%, C: 1.6%, and O: 3.3%, respectively. The permeation section in this embodiment is fabricated by permeating SiO2 into the composite material made of Fe96.5Si3.5 magnetic powder and epoxy resin (i.e., the core). The difference between Embodiment 3 and Embodiment 2 lies in the thickness of the permeation section; in Embodiment 3, the thickness of the permeation section is 30–50 micrometers. The device is a wire-wound inductor, comprising a magnetic powder core and an enameled coil. The enameled coil is copper wire coated with insulating varnish, with a circular or rectangular cross-section. Table 1 shows the test results for the effective permeability at 100kHz, volumetric power loss at 100kHz and 100mT, and DC bias capability at 100Oe in Example 3, compared to Comparative Example 1. Compared to Comparative Example 2, the solution in Example 3 has significant advantages.

[0079] Example 4

[0080] This embodiment provides a high-saturation, high-resistivity magnetic powder core and its device. The magnetic powder core comprises a core body and a surface coating. The surface coating is the same as that in Embodiment 1. The core body comprises a permeation portion and a core portion. The mass percentages of Fe, Si, B, Cr, C, and O in the core portion of the magnetic powder core are Fe: 87.1%, Si: 4.6%, B: 1.6%, Cr: 3.5%, C: 1.2%, and O: 2.0%, respectively. The raw material for the core portion in this embodiment is Fe. 88.9 Si 5.7 B 2.2 C 0.8 Cr 2.4 A composite material made of magnetic powder and epoxy resin. The mass percentages of Fe, Si, B, Cr, C, and O in the permeated portion of the magnetic powder core are Fe: 83.2%, Si: 6.5%, B: 1.4%, Cr: 3.3%, C: 1.8%, and O: 3.8%, respectively, and the thickness of the permeated portion is 250-300 micrometers. The fabrication process of the permeated portion in the embodiment is as follows: [The text abruptly ends here, so the translation stops as well.]96.5 Si 3.5 SiO2 is infiltrated into the composite material made of magnetic powder and epoxy resin (i.e., the core). The above device is a wire-wound inductor, which includes a magnetic powder core and an enameled coil. The enameled coil is a copper wire coated with insulating varnish, with a circular or rectangular cross-section. The effective permeability at 100 kHz, the volumetric power loss at 100 kHz and 100 mT, and the DC bias capability at 100 Oe of Example 4 and Comparative Example 3 are shown in Table 1. Compared with Comparative Example 3, the scheme of Example 4 has obvious advantages.

[0081] Comparative Example 3

[0082] This comparative example provides a magnetic powder core and its device. The magnetic powder core body does not contain a permeation portion, and the device is a wire-wound inductor. Other structures and preparation methods are the same as in Example 4, so they will not be described again.

[0083] Table 1

[0084]

[0085] As shown in Table 1:

[0086] 1. The embodiments of the present invention have a DC bias capability that is more than 2% better than that of the comparative examples, which is a significant improvement.

[0087] 2. In existing technologies, the doping of insulating materials typically involves large quantities, diluting the magnetic material and significantly reducing permeability. However, the method for manufacturing the magnetic powder core and its device / inductor in this embodiment of the invention introduces less insulating material, resulting in a smaller reduction in permeability. Therefore, the method for manufacturing the magnetic powder core and its device / inductor in this embodiment of the invention does not improve permeability.

[0088] 3. The simultaneous presence of low power loss and high DC bias capability demonstrates that the magnetic powder core and its devices / inductors in the embodiments of the present invention simultaneously achieve high resistivity and high saturation magnetization.

[0089] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, several equivalent substitutions or obvious modifications can be made without departing from the concept of the present invention, and all such modifications, achieving the same performance or purpose, should be considered within the scope of protection of the present invention.

Claims

1. A high-saturation, high-resistivity magnetic powder core, characterized in that, The core comprises a core and a permeation layer, the permeation layer covering the core. The resistivity of the core is lower than that of the permeation layer, and the saturation magnetization of the core is greater than that of the permeation layer. During the formation of the high-resistivity permeation layer on the surface of the magnetic powder core, the microstructure of the core remains unchanged. The elements and their contents in the core are: Fe 83-97 wt%, Si 1-9 wt%, and at least one of Al, Cr, B, C, and O. The thickness of the permeation layer is 10 to 300 micrometers. The raw materials used to fabricate the permeation layer are at least one of nano-SiO2, Al2O3, MgO, ZnO, and Cr2O3.

2. The high-saturation, high-resistivity magnetic powder core according to claim 1, characterized in that, The elements and their contents in the permeation section are: Fe 81-96 wt%, Si 2-11 wt%, and also include at least one of Al, Cr, B, C, and O.

3. The high-saturation, high-resistivity magnetic powder core according to claim 2, characterized in that, When the permeation section contains Al, the Al content is 0.5~8 wt%; When the permeation section contains Cr, the Cr content is 0.5~8 wt%; When the permeation section contains B, the content of B is 0.5~8 wt%; When the permeation section contains C, the C content is 0.5~8wt%; When the permeation section contains O, the O content is 0.5~5wt%.

4. The high-saturation, high-resistivity magnetic powder core according to claim 1, characterized in that, When the core contains Al, the Al content is 0.5~8 wt%; When the core contains Cr, the Cr content is 0.5~8wt%; When the core contains B, the content of B is 0.5~8 wt%; When the core contains carbon, the carbon content is 0.5~8 wt%; When the core contains O, the O content is 0.3~2wt%.

5. The high-saturation, high-resistivity magnetic powder core according to claim 1, characterized in that, It also includes a surface coating, which is located on the outermost layer and covers the permeation portion.

6. A method for manufacturing a high-saturation, high-resistivity magnetic powder core, used to manufacture a high-saturation, high-resistivity magnetic powder core as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1: The core of the high-saturation, high-resistivity magnetic powder core is obtained by powder coating, granulation, pressing and molding, and sintering. S2: Using a coating-diffusion heat treatment or vacuum impregnation method, insulating particles are coated on the surface of the core and allowed to penetrate into the surface layer of the core to obtain the high-saturation, high-resistivity magnetic powder core with the penetrating part covering the core.

7. An inductor, characterized in that, It includes a high-saturation, high-resistivity magnetic powder core and a coil as described in any one of claims 1 to 5, wherein the coil is wound around the surface of the high-saturation, high-resistivity magnetic powder core.

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