Preparation and application of high-frequency ultralow-loss soft magnetic composite material

Abstract

The invention provides a method for preparing a high-frequency ultralow-loss soft magnetic composite material, and the method comprises the following steps: (1) iron alloy soft magnetic powder and ferrite powder are provided, the D50 particle size range of the iron alloy soft magnetic powder is 1-100 [mu] m, the average particle size of the ferrite powder is 1-100 nm, and the average particle size of the ferrite powder is 1-100 nm; the ferrite powder is prepared by a coprecipitation method; the mass ratio of the ferrite powder to the iron alloy soft magnetic powder is (0.05: 100)-(10: 100); (2) mixing and grinding the iron alloy soft magnetic powder and the ferrite powder in the step (1) for a period of time to obtain composite powder; (3) adding an adhesive into the composite powder in the step (2), uniformly mixing and granulating to obtain granulated composite powder; and (4) adding a lubricant into the granulated composite powder in the step (3), and mixing to prepare the high-frequency ultralow-loss soft magnetic composite material. According to the high-frequency ultra-low-loss soft magnetic composite material prepared by the invention, the hysteresis loss and the eddy-current loss of the composite material can be remarkably reduced.

Description

Technical Field

[0001] This invention belongs to the field of magnetic component technology and relates to a method for preparing insulating coated soft magnetic alloy powder, specifically a soft magnetic composite material with low loss at high frequencies and its preparation method. Background Technology

[0002] Inductors, playing crucial roles in circuits such as energy storage, filtering, oscillation, and tuning, are a vital class of electronic components. The magnetic core, the core component of an inductor, is composed of various soft magnetic materials depending on its function. With the rapid development of artificial intelligence, new energy vehicles, and 5G communications, higher demands are being placed on inductors for higher frequencies, smaller size, and higher power. Among all soft magnetic materials, soft magnetic composite materials (SMCs) possess both high saturation magnetic flux density and high resistivity, showing potential applications in power inductors and next-generation AI computing and chip inductors. FeSiAl magnetic powder cores, in particular, are soft magnetic materials with near-zero magnetostriction and magnetocrystalline anisotropy, meeting the miniaturization and integration requirements of power electronic devices and representing the fastest-growing magnetic material in terms of development and application. However, with the commercialization of third-generation semiconductors such as silicon carbide and gallium nitride, the frequency of inductors has increased from hundreds of kilohertz to megahertz, but current SMCs struggle to meet these demands, primarily due to their extremely high eddy current losses at megahertz frequencies.

[0003] To reduce high-frequency losses, insulating coating of SMCs is an essential process. Currently, mainstream insulating coating methods include phosphating, organic coating, and inorganic coating. Organic coating generally uses volatile chemicals such as epoxy resins and silicone resins, which can pollute the environment. Furthermore, the inductance of the magnetic core usually decreases significantly after baking. While traditional phosphating is low-cost, the resulting insulating layer is not heat-resistant and is prone to cracking and peeling during high-temperature annealing. Inorganic coating, such as using physical or chemical methods to coat oxides with high resistivity, like magnesium oxide, aluminum oxide, and silicon dioxide, while heat-resistant, is prone to agglomeration and poor dispersibility, leading to uneven powder coating and difficulty in obtaining low-loss magnetic powder cores. Additionally, because these oxides are non-magnetic, their addition to the SMC system causes severe magnetic dilution, resulting in a significant decrease in the permeability and saturation magnetization of the SMCs.

[0004] Ferrites, inherently soft magnetic materials with high resistivity, can be used to insulate SMCs (Silicon-Metal-Aluminum Composites), significantly mitigating magnetic dilution while reducing high-frequency eddy current losses. For example, some literature reports the use of a solvothermal method to prepare manganese-zinc ferrite for insulating coating of iron-silicon-aluminum powders, resulting in improved permeability of the composite. Other literature reports the in-situ growth of nickel-zinc ferrite on sheet-like iron-silicon-aluminum surfaces, achieving a total volumetric loss approaching 10000 mW / cm² at 1 MHz / 50 mT. 3 The loss of uncoated iron-silicon-aluminum powder is as high as 30,000 mW / cm³. 3 This indicates that ferrite coating can effectively reduce losses at high frequencies. However, for applications under megahertz conditions, the losses of SMCs obtained by the above method are still too high and cannot meet application requirements. Summary of the Invention

[0005] On one hand, the present invention provides a method for preparing high-frequency ultra-low loss soft magnetic composite materials, the method comprising the following steps:

[0006] (1) Provides ferroalloy soft magnetic powder and ferrite powder, wherein the D50 particle size range of the ferroalloy soft magnetic powder is 1μm-100μm, and the average particle size of the ferrite powder is 1nm-100nm, and the ferrite powder is prepared by co-precipitation method; the mass ratio of the ferrite powder to the ferroalloy soft magnetic powder is 0.05:100-10:100.

[0007] (2) The iron alloy soft magnetic powder and ferrite powder from step (1) are mixed and ground for a period of time to obtain composite powder;

[0008] (3) Add adhesive to the composite powder in step (2), mix and granulate to obtain granulated composite powder;

[0009] (4) In step (3), lubricant is added to the granulated composite powder to prepare a high-frequency ultra-low loss soft magnetic composite material.

[0010] In one embodiment, the D50 particle size range of the iron alloy soft magnetic powder in step (1) is 1μm-15μm, for example, 5μm-10μm, or 6μm, 7μm, 8μm, 9μm.

[0011] In one embodiment, the average particle size of the ferrite powder is 10nm-50nm, for example, 20nm, 30nm, or 40nm.

[0012] In one embodiment, the mass ratio of the ferrite powder to the iron alloy soft magnetic powder is 0.05:100-5:100, for example, 1:100, 2:100, 3:100, or 4:100.

[0013] In one embodiment, the ferrite powder is prepared by a coprecipitation method, which includes mixing and dissolving the raw materials in a solvent in a certain proportion, heating, adjusting to a suitable pH for reaction, collecting the precipitate, drying to obtain a ferrite powder precursor, and then sintering under anaerobic conditions to obtain the ferrite powder.

[0014] In one embodiment, the solvent of the coprecipitation method contains organic macromolecules or small molecules that can form cage-like or network structures, such as poly(4-styrenesulfonic acid-copolymer-maleic acid), PEG, ferritin, bovine serum albumin, viral capsid protein, or citric acid, or a combination of the above molecules; preferably, poly(4-styrenesulfonic acid-copolymer-maleic acid).

[0015] Preferably, the molar ratio of 4-styrenesulfonic acid to maleic acid in the poly(4-styrenesulfonic acid-copolymer-maleic acid) is 1:1 or 3:1, preferably 3:1.

[0016] In one embodiment, the amount (mass / volume) of the poly(4-styrenesulfonic acid-copolymer-maleic acid) is 0.1%-5%, for example, 0.5%, 1%, 2%, 3%, 4%.

[0017] In one embodiment, the iron alloy soft magnetic powder is selected from at least one of iron-silicon-aluminum soft magnetic alloy powder, iron-nickel soft magnetic alloy powder, iron-silicon soft magnetic alloy powder, iron-silicon-chromium soft magnetic alloy powder, iron-nickel-molybdenum soft magnetic alloy powder, amorphous / nanocrystalline soft magnetic alloy powder, and carbonyl iron powder; preferably, it is iron-silicon-aluminum soft magnetic alloy powder.

[0018] In one embodiment, the ferrite powder is selected from at least one of nickel-zinc ferrite powder, manganese-zinc ferrite powder, copper-zinc ferrite powder, manganese ferrite powder, nickel ferrite powder, cobalt ferrite powder, and zinc ferrite powder; preferably, nickel-zinc ferrite powder.

[0019] In one embodiment, grinding in step (2) takes 10 to 60 minutes, for example, 20, 30, 40 or 50 minutes.

[0020] In one embodiment, the adhesive in step (3) is prepared using silicone resin or epoxy resin and acetone solution.

[0021] In one embodiment, the lubricant in step (4) is aluminum stearate or zinc stearate lubricant.

[0022] In a preferred embodiment, the ferrite powder is nickel-zinc ferrite powder, and the method for preparing the nickel-zinc ferrite powder includes the following steps:

[0023] Weigh out the trivalent iron salt, divalent nickel salt, and divalent zinc salt in proportion, or weigh out the hydrates of the trivalent iron salt, divalent nickel salt, and divalent zinc salt in proportion; dissolve them in water, stir, and heat; adjust the pH to ≥12, and continue stirring for a period of time; after the reaction is complete, collect the precipitate and wash it until the pH is less than 11 (e.g., less than 10, 9, or 8); dry to obtain the nickel-zinc ferrite powder precursor; then sinter it at 300℃-800℃ under a nitrogen or argon atmosphere for a period of time (e.g., 2-4 hours) to obtain the nickel-zinc ferrite powder.

[0024] In one embodiment, the trivalent iron salt is selected from any one or more of Fe2(SO4)3, FeCl3, and Fe(NO3)3.

[0025] In one embodiment, the divalent nickel salt is selected from any one or more of NiSO4, NiCl2, and Ni(NO3)2.

[0026] In one embodiment, the divalent zinc salt is selected from any one or more of ZnSO4, ZnCl2, and Zn(NO3)2.

[0027] In a more preferred embodiment, the method for preparing the nickel-zinc ferrite powder includes the following steps:

[0028] Add poly(4-styrenesulfonic acid-copolymer-maleic acid) to water to obtain a PSS-MA solution; weigh out ferric salt, nickel salt and zinc salt in proportion, or weigh out hydrates of ferric salt, nickel salt and zinc salt in proportion; dissolve in the above PSS-MA solution, stir and heat; adjust pH ≥ 12, and continue stirring for a period of time; after the reaction is complete, collect the precipitate and wash until pH is less than 11 (e.g., pH less than 10, 9 or 8); dry to obtain nickel-zinc ferrite powder precursor; then sinter at 300℃-800℃ under nitrogen or argon atmosphere for a period of time (e.g., 2-4h) to obtain nickel-zinc ferrite powder.

[0029] On the other hand, the present invention also provides a high-frequency ultra-low loss soft magnetic composite material prepared by the above method.

[0030] The high-frequency ultra-low loss soft magnetic composite material prepared by this invention can significantly reduce the hysteresis loss of the composite material. Attached Figure Description

[0031] Figure 1 TEM images of the morphology of nickel-zinc ferrites prepared by different methods.

[0032] Figure 2 SEM images of iron-silicon-aluminum raw powder and nickel-zinc ferrite prepared by different methods after coating iron-silicon-aluminum particles. Detailed Implementation

[0034] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0035] In this invention, unless otherwise specified, all raw materials are available from the market or are commonly used in this industry. The methods in the following embodiments are conventional methods in the art.

[0036] Example 1

[0037] This embodiment prepares nano-ferrites via a co-precipitation method, and the preparation method of the nano-ferrites includes the following steps:

[0038] (1) Weigh 1.6 g of Fe2(SO4)3·7H2O, 0.475 g of NiSO4·6H2O and 0.575 g of ZnSO4 into 200 ml of deionized water, dissolve them in the solution, stir mechanically for 30 minutes and heat to 80 °C.

[0039] (2) Slowly add 10 mol / L NaOH solution to the suspension to adjust the pH to 12, and continue mechanical stirring at 80°C for 30 minutes.

[0040] (3) After the reaction is complete, the precipitate is collected and then washed with deionized water until the pH value of the suspension is less than 11. The precipitate is dried in an oven at 80°C to obtain NiZn nano ferrite powder precursor, and then sintered at 500°C under nitrogen for 3 hours to obtain NiZn nano ferrite powder.

[0041] Example 2

[0042] This embodiment provides a nano-ferrite based on the concept of biomimetic mineralization and through a confined mineralization method. The preparation method of the nano-ferrite includes the following steps:

[0043] (1) Add 1 gram of poly(4-styrenesulfonic acid-copolymer-maleic acid) (PSS-MA3∶1, molecular weight about 20,000) to 200 ml of deionized water, stir mechanically for 30 minutes, and heat to 80°C.

[0044] (2) Weigh out 1.6 g of Fe2(SO4)3·7H2O, 0.475 g of NiSO4·6H2O, and 0.575 g of ZnSO4 respectively, and dissolve them in the PSS-MA solution in step (1). Stir at 80°C for 30 minutes. Then, slowly add 10 mol / L NaOH solution to the suspension to adjust the pH to 12, and continue mechanical stirring at 80°C for 30 minutes.

[0045] (3) After the reaction is complete, the precipitate is collected and then washed with deionized water until the pH value of the suspension is less than 11. The precipitate is dried in an oven at 80°C to obtain NiZn nano ferrite powder precursor, and then sintered at 500°C under nitrogen for 3 hours to obtain NiZn nano ferrite powder.

[0046] Example 3

[0047] This embodiment provides a nano-ferrite / metal soft magnetic composite material, and the preparation method of the insulating coated soft magnetic powder includes the following steps:

[0048] (1) Take 30 grams of iron-silicon-aluminum powder and put it into a mortar. The D50 of the powder is 9 micrometers. Add 0.5 wt% of nano ferrite, specifically 0.15 grams of nano ferrite prepared in Example 1. Perform mechanical grinding for 20 minutes to obtain composite powder.

[0049] (2) Take 0.3g of silicone resin and add it to 2g of acetone solution and mix thoroughly to obtain an adhesive;

[0050] (3) Granulation and drying: Add the adhesive prepared in step (2) to the composite powder, stir evenly into a slurry, granulate, and bake in a 60℃ oven for 70 minutes to obtain granulated composite powder.

[0051] (4) The granulated composite powder is sieved through a 100-mesh screen, and aluminum stearate lubricant is added at 0.5% of the mass of the sieved composite powder to mix and obtain an integrally molded high-frequency low-loss soft magnetic composite material for inductors.

[0052] (5) Place the high-frequency, low-loss soft magnetic composite powder from step (4) into a mold and hold it under pressure of 1500MPa for 1 minute to obtain a magnetic ring.

[0053] Example 4

[0054] The difference between this embodiment and Example 3 is that the amount of nano-ferrite added is 1 wt%, that is, 0.3 g of nano-ferrite prepared in Example 1 is added to 30 g of iron-silicon-aluminum powder and mechanically ground for 20 minutes to obtain composite powder.

[0055] Example 5

[0056] The difference between this embodiment and Example 3 is that the amount of nano-ferrite added is 2wt%, that is, 0.6g of nano-ferrite prepared in Example 1 is added to 30g of iron-silicon-aluminum powder and mechanically ground for 20 minutes to obtain composite powder.

[0057] Example 6

[0058] The difference between this embodiment and Example 3 is that the amount of nano-ferrite added is 3wt%, that is, 0.9g of nano-ferrite prepared in Example 1 is added to 30g of iron-silicon-aluminum powder and mechanically ground for 20 minutes to obtain composite powder.

[0059] Example 7

[0060] This embodiment provides a nano-ferrite / metal soft magnetic composite material, and the preparation method of the insulating coated soft magnetic powder includes the following steps:

[0061] (1) Take 30 grams of iron-silicon-aluminum powder and put it into a mortar. The powder has a D50 of 9 micrometers. Add 0.5 wt% of nano ferrite, specifically 0.15 grams of nano ferrite prepared in Example 2. Perform mechanical grinding for 20 minutes to obtain composite powder.

[0062] (2) Take 0.3g of silicone resin and add it to 2g of acetone solution and mix thoroughly to obtain an adhesive;

[0063] (3) Granulation and drying: Add the adhesive prepared in step (2) to the composite powder, stir evenly into a slurry, granulate, and bake in a 60℃ oven for 70 minutes to obtain granulated composite powder.

[0064] (4) The granulated composite powder is sieved through a 100-mesh screen, and aluminum stearate lubricant is added at 0.5% of the mass of the sieved composite powder to mix and obtain a high-frequency low-loss soft magnetic composite material.

[0065] (5) Place the high-frequency, low-loss soft magnetic composite powder from step (4) into a mold and hold it under pressure of 1500MPa for 1 minute to obtain a magnetic ring.

[0066] Example 8

[0067] The difference between this embodiment and Example 7 is that the amount of nano-ferrite added is 1 wt%, that is, 0.3 g of nano-ferrite prepared in Example 2 is added to 30 g of iron-silicon-aluminum powder and mechanically ground for 20 minutes to obtain composite powder.

[0068] Example 9

[0069] The difference between this embodiment and Embodiment 7 is that the amount of nano-ferrite added is 2wt%, that is, 0.6g of the nano-ferrite prepared in Embodiment 2 is added to 30g of iron-silicon-aluminum powder, and mechanically ground for 20 minutes to obtain composite powder.

[0070] Example 10

[0071] The difference between this embodiment and Embodiment 7 is that the amount of nano-ferrite added is 3wt%, that is, 0.9g of the nano-ferrite prepared in Embodiment 2 is added to 30g of iron-silicon-aluminum powder, and mechanically ground for 20 minutes to obtain composite powder.

[0072] Example 11

[0073] This embodiment provides a nano-ferrite / metal soft magnetic composite material, and the preparation method of the insulating coated soft magnetic powder includes the following steps:

[0074] (1) Take 30 grams of iron-silicon-aluminum powder and put it into a mortar. Add 2 wt% ferrite, specifically 0.6 grams of ball milling nickel-zinc ferrite, and grind for 20 minutes.

[0075] (2) Take 0.3g of silicone resin, add it to 2g of acetone solution and mix thoroughly to obtain adhesive;

[0076] (3) Granulation and drying: Add the adhesive prepared in step (2) to the composite powder, stir evenly into a slurry, granulate, and bake in a 60℃ oven for 70 minutes to obtain granulated powder.

[0077] (4) The granulated composite powder is sieved through a 100-mesh sieve, and aluminum stearate lubricant is added at 0.5% of the mass of the sieved composite powder to be mixed to obtain the material;

[0078] (5) Place the powder from step (4) into the mold and hold it under pressure of 1500MPa for 1 minute to obtain the magnetic ring.

[0079] Comparative Example 1

[0080] (1) Take 30 grams of iron-silicon-aluminum powder and put it into a mortar. Do not add nano ferrite. Use it directly for subsequent granulation.

[0081] (2) Take 0.3g of silicone resin, add it to 2g of acetone solution and mix thoroughly to obtain adhesive;

[0082] (3) Granulation and drying: Add the adhesive prepared in step (2) to the composite powder, stir evenly into a slurry, granulate, and bake in a 60℃ oven for 70 minutes to obtain granulated powder.

[0083] (4) The granulated composite powder is sieved through a 100-mesh sieve, and aluminum stearate lubricant is added at 0.5% of the mass of the sieved composite powder to be mixed to obtain the material;

[0084] (5) Place the powder from step (4) into the mold and hold it under pressure of 1500MPa for 1 minute to obtain the magnetic ring.

[0085] Table 1. Performance test results of magnetic rings obtained in each embodiment and comparative example.

[0086]

[0087] Figure 1 These are TEM images of the morphology of nickel-zinc ferrites prepared by biomimetic confined mineralization (a) (Example 2), coprecipitation (b) (Example 1), and ball milling (c) (Example 11), respectively. The images show that the nickel-zinc ferrites prepared by biomimetic confined mineralization have the smallest particle size, with an average particle size of approximately 15.7 nm, and exhibit the best dispersibility. The nickel-zinc ferrites prepared by coprecipitation have a particle size of approximately 31 nm, but exhibit very poor dispersibility and severe aggregation. The nickel-zinc ferrites prepared by ball milling, due to the inherent limitations of the method, have particle sizes that are primarily in the micrometer range, which is unfavorable for insulating coating of iron, silicon, and aluminum.

[0088] Figure 2 The images show SEM images of raw iron-silicon-aluminum powder (a) and nickel-zinc ferrites prepared by ball milling (b), co-precipitation (c), and biomimetic confined mineralization (d) respectively, after coating the iron-silicon-aluminum particles. The images show that the surface of the raw iron-silicon-aluminum powder is smooth. The ferrite prepared by ball milling has the worst coating effect on the iron-silicon-aluminum, with only a small number of large particles adhering to the surface. Since the ferrite prepared by co-precipitation also has a nanometer-sized particle size, it can coat a portion of the particles. The best coating effect is achieved by the ferrite prepared by biomimetic confined mineralization, which has a smaller particle size, better dispersibility, and can achieve uniform and complete coating of the iron-silicon-aluminum.

[0089] In addition, as shown in Table 1, the composite material with added nano-ferrites has significantly reduced losses compared to the material without added nano-ferrites.

[0090] Compared to Comparative Example 1, the nickel-zinc ferrite prepared by co-precipitation and biomimetic synthesis in Examples 3-10 for insulating the iron-silicon-aluminum composite material can reduce high-frequency losses. Furthermore, as can be seen from Examples 3-10 and Comparative Example 1, as the amount of nickel-zinc ferrite added gradually increases, the loss first decreases and then increases, reaching its lowest point when the amount of nickel-zinc ferrite added is 2%. This indicates that the insulating coating of nickel-zinc ferrite can effectively improve the resistivity of the composite material and reduce eddy current losses at high frequencies. Further, as can be seen from Examples 3-10 and Comparative Example 1, as the amount of nickel-zinc ferrite added gradually increases, the permeability first increases and then decreases, with the highest permeability occurring when the amount of nickel-zinc ferrite is 1%. This indicates that the addition of nickel-zinc ferrite not only does not bring about a magnetic dilution effect, but also increases the permeability of the composite material. This is because nickel-zinc ferrite itself is magnetic, and an appropriate amount of nickel-zinc ferrite can fill the gaps in the iron-silicon-aluminum composite, thus increasing the permeability. When the content of nickel-zinc ferrite is excessive, the permeability begins to decrease. As can be seen from Examples 3-10, the nickel-zinc ferrite prepared by adding PSSMA has better performance. This is because PSSMA provides a confined space for mineralization, resulting in finer and more dispersed nickel-zinc ferrite particles after synthesis, which reduces the hysteresis loss of the composite material. On the other hand, the smaller particle size of the nickel-zinc ferrite provides a more complete coating of iron, silicon, and aluminum, thus reducing the eddy current loss of the composite material.

[0091] Furthermore, as can be seen from Example 11, the addition of ferrite prepared by the conventional ball milling method not only did not reduce the loss, but also increased the loss of the metal magnetic powder core by 44.6% compared with the original powder.

[0092] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for preparing high-frequency ultra-low loss soft magnetic composite materials, the method comprising the following steps: (1) Provides ferroalloy soft magnetic powder and ferrite powder, wherein the D50 particle size range of the ferroalloy soft magnetic powder is 1μm-100μm, and the average particle size of the ferrite powder is 1nm-100nm, and the ferrite powder is prepared by co-precipitation method; the mass ratio of the ferrite powder to the ferroalloy soft magnetic powder is 0.05:100-10:

100. (2) The iron alloy soft magnetic powder and ferrite powder from step (1) are mixed and ground for a period of time to obtain composite powder; (3) Add adhesive to the composite powder in step (2), mix and granulate to obtain granulated composite powder; (4) In step (3), lubricant is added to the granulated composite powder to prepare a high-frequency ultra-low loss soft magnetic composite material.

2. The method according to claim 1, characterized in that, The D50 particle size range of the iron alloy soft magnetic powder in step (1) is 1μm-15μm; the average particle size of the ferrite powder is 10nm-50nm.

3. The method according to claim 1, characterized in that, The mass ratio of ferrite powder to iron alloy soft magnetic powder is 0.5:100-5:

100.

4. The method according to claim 1, characterized in that, In step (1), the coprecipitation method includes mixing and dissolving each raw material in a solvent in a certain proportion, heating, adjusting to a suitable pH for reaction, collecting the precipitate, drying to obtain ferrite powder precursor, and then sintering under anaerobic conditions to obtain ferrite powder.

5. The method according to claim 4, characterized in that, The solvent of the coprecipitation method contains organic macromolecules or small molecules that can form cage-like or network structures, such as poly(4-styrenesulfonic acid-copolymer-maleic acid), PEG, ferritin, bovine serum albumin, viral capsid protein, or citric acid, or a combination of the above molecules; preferably, poly(4-styrenesulfonic acid-copolymer-maleic acid).

6. The method according to claim 5, characterized in that, The molar ratio of 4-styrenesulfonic acid to maleic acid in the poly(4-styrenesulfonic acid-copolymer-maleic acid) is 1:1 or 3:1, preferably 3:

1.

7. The method according to claim 5, characterized in that, The amount (mass / volume) of the poly(4-styrenesulfonic acid-copolymer-maleic acid) is 0.1%-5%.

8. The method according to claim 1, characterized in that, The iron alloy soft magnetic powder is selected from at least one of the following: iron-silicon-aluminum soft magnetic alloy powder, iron-nickel soft magnetic alloy powder, iron-silicon soft magnetic alloy powder, iron-silicon-chromium soft magnetic alloy powder, iron-nickel-molybdenum soft magnetic alloy powder, amorphous / nanocrystalline soft magnetic alloy powder, and carbonyl iron powder.

9. The method according to claim 1, characterized in that, The ferrite powder is selected from at least one of nickel-zinc ferrite powder, manganese-zinc ferrite powder, copper-zinc ferrite powder, manganese ferrite powder, nickel ferrite powder, cobalt ferrite powder, and zinc ferrite powder.

10. A high-frequency ultra-low loss soft magnetic composite material prepared by any one of the methods of claims 1-9.

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