A laminated soft magnetic composite and a method of manufacturing the same

Abstract

The application discloses a laminated soft magnetic composite material and a preparation method thereof. The composite material is formed by alternately stacking insulating layers and magnetic conductive layers along the thickness direction. The insulating layer is formed by amorphous and / or nanocrystalline soft magnetic alloy spherical powder through a flow casting process, aiming to form a high-resistance area to inhibit eddy current loss. The magnetic conductive layer is formed by amorphous and / or nanocrystalline soft magnetic alloy flaky powder through a flow casting process, aiming to form a low-magnetic-resistance area to improve the magnetic permeability. The preparation method comprises the following steps: preparing spherical powder and flaky powder; preparing corresponding flow casting films respectively; alternately stacking the two flow casting films to form a laminated preform; adopting a two-step pressing process of low-pressure fitting first and high-pressure densification later to form; and finally, heat treatment. Through structure design and process adaptation, the application can effectively reduce the forming stress while ensuring high density, so that the material has high magnetic permeability, low loss and high quality factor under the condition of 1MHz and 10mT, and is suitable for high-frequency electronic components.

Description

Technical Field

[0001] This invention belongs to the field of soft magnetic composite material technology, specifically relating to a layered soft magnetic composite material and its preparation method. Background Technology

[0002] With the trend towards higher frequencies and miniaturization in electronic power devices, soft magnetic composite materials need to simultaneously meet the requirements of low loss and high permeability. Amorphous and / or nanocrystalline soft magnetic alloys are considered ideal magnetic phases for preparing high-frequency soft magnetic composite materials due to their low coercivity and high resistivity. However, these alloys themselves have extremely high strength (approximately 4000 MPa), which presents a key technical challenge in their molding process: to obtain sufficient density to ensure high permeability, very high molding pressure must be used; but extremely high molding pressure introduces significant residual stress, which impairs the soft magnetic properties of the material, manifesting as increased loss and decreased permeability.

[0003] To improve the performance of amorphous and / or nanocrystalline soft magnetic composite materials, existing technologies mainly focus on two approaches: process optimization and material composite methods. Regarding process optimization, for example, hot pressing (e.g., CN120072501A) can be used to increase the molding temperature and reduce the required pressure. However, the high-temperature environment easily leads to the decomposition and failure of the organic insulating coating, damaging the insulation integrity and increasing eddy current losses. Alternatively, multi-stage heat treatment (e.g., CN119419028A) can be used to fully release internal stress, but the process is complex and imposes stringent requirements on the thermal stability of the insulating layer. Regarding material composite methods, for example, the introduction of a highly ductile iron-nickel alloy (FeNi) can improve pressing performance, and high-resistivity manganese-zinc ferrite can be composited to reduce eddy current losses (e.g., CN118866496A). However, this method often achieves this by introducing non-magnetic or weakly magnetic phases, which essentially sacrifices the saturation magnetization of the material, limiting the full realization of its magnetic permeability potential.

[0004] It is evident that existing improvement methods are adjustments and compromises based on existing foundations, failing to address the fundamental contradiction between high-density molding and low stress, high performance through innovative structural design. Summary of the Invention

[0005] The purpose of this invention is to solve the aforementioned technical problems existing in the prior art and to provide a layered soft magnetic composite material and its preparation method. This material, through a unique structural design of alternating layers of insulating and magnetically conductive layers, combined with a suitable two-step pressing process, can achieve high densification of the material while controlling molding stress, thereby obtaining excellent comprehensive soft magnetic properties that combine high permeability, low loss, and high stability.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a layered soft magnetic composite material, characterized by its macroscopic layered structure: it is not composed of a uniform mixture of magnetic powders of a single form, but rather of two functionally different structural layers alternately stacked along its thickness direction. Specifically, one layer is an insulating layer formed by amorphous and / or nanocrystalline soft magnetic alloy spherical powder through a casting process, and the other layer is a magnetically conductive layer formed by amorphous and / or nanocrystalline soft magnetic alloy sheet powder through a casting process. These two functional layers are combined into a dense whole through a specific two-step pressing and subsequent heat treatment process. The insulating layer mainly utilizes the characteristic that spherical powder is easily coated by an insulating medium to form a high resistivity region and effectively suppress eddy current losses; the magnetically conductive layer utilizes the planar easy magnetization characteristic of sheet powder to form a low magnetic resistance region and provide high magnetic permeability.

[0008] In a preferred embodiment, the magnetic matrix constituting the insulating layer and the magnetic conductive layer is an iron-based amorphous and / or nanocrystalline soft magnetic alloy. A representative alloy system has the following general chemical formula:

[0009] Fe (100-a-b-c-d-e-f-g-h) Co a Ni b Si c B d P e C f Nb g Cu h ;

[0010] By adjusting the contents of elements such as cobalt (Co), nickel (Ni), silicon (Si), boron (B), phosphorus (P), carbon (C), niobium (Nb), and copper (Cu), the amorphous forming ability, thermal stability, and magnetic properties of the alloy can be controlled.

[0011] The atomic percentages of each element preferably satisfy the following: 0≤a≤20.0; 0≤b≤20.0; 2.0≤c≤13.5; 6.0≤d≤9.0; 0≤e≤5.0; 0≤f≤2.0; 0≤g≤3.0; 0≤h≤1.5.

[0012] To control the overall magnetic properties of the final composite material, the relative thickness ratio of the insulating layer to the magnetically conductive layer can be adjusted. Preferably, the thickness ratio of the single layer of the insulating layer to the magnetically conductive layer is between 0.2:1 and 5:1. This design allows for optimization of the proportion of magnetically conductive channels in the magnetic circuit while ensuring sufficient interlayer insulation.

[0013] Based on the unique structural design described above, the composite material provided by this invention exhibits excellent soft magnetic properties when tested at a frequency of 1MHz and a magnetic flux density of 10mT: its effective permeability μe≥30, while the magnetic loss Pcv is not higher than 200kW / m³, and the quality factor Q is not lower than 55, achieving a good balance between high permeability and low loss.

[0014] Secondly, the present invention provides a method for preparing the above-mentioned laminated soft magnetic composite material. This method aims to achieve complete construction and low-stress densification of an alternating laminated structure of insulating and magnetically conductive layers, and includes the following steps:

[0015] S1. Provides spherical powder and flake powder of amorphous and / or nanocrystalline soft magnetic alloys. The spherical powder can be prepared by atomization; the flake powder can be prepared into corresponding amorphous ribbons by melt quenching methods such as single-roller rapid quenching or double-roller rapid quenching. Melt quenching can be carried out under a protective atmosphere of air, vacuum (e.g., vacuum degree better than 0.1 Pa), or inert gas (e.g., nitrogen or argon with purity better than 99.9%), followed by embrittlement heat treatment and ball milling. The embrittlement heat treatment is preferably carried out in the temperature range between 200°C below the alloy's crystallization temperature and the crystallization temperature, and the treatment time can be 30 to 240 minutes. In the ball milling process, controlling the mass ratio of grinding balls to powder (ball-to-powder ratio) between 20:1 and 50:1 helps to obtain flake powder with a suitable aspect ratio.

[0016] S2. Preparation of Cast Film: Spherical powder is mixed with binder and solvent to form a spherical powder casting slurry, which is then cast and dried to obtain a spherical powder cast film. Flake powder is mixed with binder and solvent to form a flake powder casting slurry, which is then cast and dried to obtain a flake powder cast film. The binder can be selected from at least one of polyvinyl butyral, polyurethane, and silicone resin. To further adjust the process performance and final insulation, plasticizers and / or insulating fillers can be selectively added to the casting slurry. The plasticizer can be selected from at least one of dibutyl phthalate and dimethyl silicone oil; the insulating filler can be nano-sized silica. The thickness of the obtained single-layer cast film is preferably controlled between 90 and 500 micrometers. After drying and subsequent processes, the binder, plasticizer, and insulating filler work together in the final composite material to bond and form the magnetic powder particles and to insulate them from each other.

[0017] S3. Alternately stack spherical powder cast films and sheet powder cast films to form a laminated preform. For example, they can be stacked in the order of one insulating film and one magnetic conductive film.

[0018] S4. The laminated preform is pressed and formed by first applying a first pressure P1 and holding it for a first time t1, and then applying a second pressure P2, which is greater than P1, and holding it for a second time t2 to obtain the composite material precursor. The first pressure P1 can be 400 to 1000 MPa, and the holding time t1 can be 5 to 45 seconds; the second pressure P2 can be 800 to 2400 MPa, and the holding time t2 can be 10 to 90 seconds. This two-step pressing method, involving low-pressure bonding followed by high-pressure densification, effectively alleviates interlayer stress concentration and structural damage caused by one-time high-pressure molding.

[0019] S5. Heat-treat the composite material precursor to eliminate molding internal stress, or crystallize it as needed, to obtain a laminated soft magnetic composite material.

[0020] Thirdly, based on the excellent high-frequency soft magnetic properties of the composite material of the present invention, it is suitable for manufacturing various high-frequency electronic components. Therefore, the present invention also provides an electronic component comprising any of the above-mentioned layered soft magnetic composite materials, which can be used as the magnetic core of devices such as high-frequency inductors and transformers.

[0021] The present invention, by adopting the above-described technical solution, has the following beneficial effects:

[0022] 1. By constructing an insulating layer and a magnetic permeable layer separately and stacking them alternately to obtain a composite structure, the synergistic effect of eddy current suppression and magnetic permeability enhancement is achieved macroscopically, providing a new design idea for solving the contradiction between high magnetic permeability and low loss.

[0023] 2. In view of the characteristics of the laminated structure, a two-step pressing process was adopted. By first bonding under low pressure and then densifying under high pressure, the residual stress of molding was significantly reduced while ensuring high density, thereby optimizing the final soft magnetic properties of the material.

[0024] 3. The prepared composite material simultaneously possesses high permeability, low loss, and high quality factor at a test frequency of 1MHz, exhibiting excellent comprehensive soft magnetic properties, making it suitable for high-frequency power electronic and communication devices with stringent requirements for efficiency and size. Attached Figure Description

[0025] The present invention will be further described below with reference to the accompanying drawings:

[0026] Figure 1 This is a schematic diagram of the cross-sectional structure of the laminated soft magnetic composite material of the present invention. Detailed Implementation

[0027] The core of this invention, the preparation of a layered soft magnetic composite material, lies in forming thin films with different functions through a casting process and employing a corresponding pressing strategy. Specifically, utilizing the characteristic that spherical powder is easily coated by an insulating medium, the resulting spherical powder casting film constitutes a high-insulation layer, aiming to form a high-resistivity region to suppress eddy current losses; utilizing the planar magnetization characteristics of flake powder, the resulting flake powder casting film constitutes a high-permeability layer, aiming to form a low-magnetic-resistivity region to improve magnetic permeability. These two functional thin films are alternately stacked and then pressed into shape. The pressing process employs a two-step method: first, a lower pressure is applied for a short time to achieve preliminary bonding and pre-densification between layers, expelling most of the interlayer air and forming a uniform and stable preform; subsequently, a higher pressure is applied for a longer time to achieve final complete densification based on the preform, filling any remaining pores. This sequence of bonding followed by densification effectively mitigates the stress damage caused to the layered structure by a single high-pressure molding process. In addition, the overall magnetic properties of the final composite material can be flexibly controlled by adjusting the relative thickness or the number of stacked layers of the insulating layer and the magnetically conductive layer cast film.

[0028] Example 1,

[0029] This embodiment prepares a layered amorphous soft magnetic composite material.

[0030] S1. Preparation of amorphous alloy spherical powder and amorphous alloy flake powder, as detailed below:

[0031] 1a) Preparation of Fe 81.7 Si2B 16 C 0.3 Amorphous spherical powder: Fe prepared by vacuum induction melting 81.7 Si2B 16 C 0.3 The master alloy (vacuum degree better than 0.1 Pa) was then pulverized using a water-gas combined atomization method under an argon protective atmosphere (purity > 99.9%) to obtain Fe. 81.7 Si2B 16 C 0.3 Amorphous spherical powder with a particle size distribution D50=25.0μm.

[0032] 1b) Preparation of Fe 78 Si9B 13 Non-crystalline powder: Fe prepared by vacuum induction melting 78 Si9B 13 The master alloy (vacuum degree better than 0.1 Pa) was then used to prepare Fe by single-roll rapid quenching and spinning under an argon protective atmosphere (purity > 99.9%). 78 Si9B 13 Amorphous ribbon. Then Fe... 78 Si9B 13The amorphous ribbon was placed in an annealing furnace and subjected to embrittlement heat treatment in a high-purity argon atmosphere. The embrittlement heat treatment temperature was 400℃, the heating rate was 10℃ / min, and the annealing time was 60min. Then, the embrittled Fe... 78 Si9B 13 Amorphous ribbon was placed in a ball mill with stainless steel grinding balls. The milling speed was 600 r / min, the ball-to-material ratio was 30:1, and the milling medium was anhydrous ethanol. The milling was carried out for 120 min to obtain Fe. 78 Si9B 13 The non-crystalline powder has a particle size of 50–200 μm, a thickness of 14–25 μm, and an aspect ratio of 8–15.

[0033] S2. Preparation of cast film:

[0034] 2a) Preparation of spherical powder cast film: 10g of Fe obtained in step S1 was used to prepare the spherical powder cast film. 81.7 Si2B 16 C 0.3 Amorphous spherical powder was mixed with 2.5g of polyvinyl butyral (PVB), 0.2g of dibutyl phthalate, 0.02g of dimethyl silicone oil, and 10g of ethanol, and ultrasonically stirred to obtain a casting slurry. The casting slurry was uniformly coated onto a fluoroethylene propylene copolymer (FEP) carrier using a doctor blade. The cast FEP carrier was then dried in a forced-air drying oven to obtain a spherical powder casting film with a thickness of 100μm.

[0035] 2b) Preparation of sheet-like powder cast film: 20g of Fe obtained in step S1 was used to prepare the film. 78 Si9B 13 Non-crystalline powder was mixed with 2.5g of polyvinyl butyral (PVB), 0.2g of dibutyl phthalate, 0.02g of dimethyl silicone oil, and 15g of ethanol, and ultrasonically stirred until homogeneous to obtain a casting slurry. The casting slurry was uniformly coated onto a fluoroethylene propylene copolymer (FEP) carrier using a doctor blade. The cast FEP carrier was then dried in a forced-air drying oven to obtain a 100μm thick flake powder casting film.

[0036] S3. Using a punching machine, cut several films with an outer diameter of 12.7 mm and an inner diameter of 7.6 mm from the spherical powder casting film and the sheet powder casting film respectively. Stack them alternately in the order of one spherical powder casting film and one sheet powder casting film, 6 of each, and place them in a mold to form a laminated preform.

[0037] S4. Press the laminated preform into shape by first holding it under 1000MPa pressure for 30s, and then holding it under 1800MPa pressure for 60s to obtain the laminated soft magnetic composite material precursor.

[0038] S5. Place the laminated soft magnetic composite material precursor in a heat treatment furnace, and under an argon protective atmosphere, heat it to 420℃ at a rate of 10℃ / min, hold it at that temperature for 60min for stress relief heat treatment, and then cool it with the furnace to obtain the laminated amorphous soft magnetic composite material product.

[0039] Comparative Example 1

[0040] Using only the spherical powder cast film obtained in step S2 of Example 1, films with an outer diameter of 12.7 mm and an inner diameter of 7.6 mm were cut from the spherical powder cast film, stacked into 12 sheets, and pressed into shape in a mold. The film was held at 1000 MPa for 30 s, then held at 1800 MPa for 60 s to obtain a spherical powder soft magnetic composite material precursor. The spherical powder soft magnetic composite material precursor was placed in a heat treatment furnace and, under an argon protective atmosphere, heated to 420°C at a rate of 10°C / min and held for 60 min for stress relief heat treatment. After furnace cooling, the finished spherical powder amorphous soft magnetic composite material was obtained.

[0041] Comparative Example 2

[0042] Using only the sheet-like powder cast film obtained in step S2 of Example 1, films with an outer diameter of 12.7 mm and an inner diameter of 7.6 mm were cut from the sheet-like powder cast film, stacked into 12 sheets, and pressed into shape in a mold. The film was held at 1000 MPa for 30 s, and then held at 1800 MPa for 60 s to obtain a sheet-like powder soft magnetic composite material precursor. The sheet-like powder soft magnetic composite material precursor was placed in a heat treatment furnace and, under an argon protective atmosphere, heated to 420°C at a rate of 10°C / min and held for 60 min for stress relief heat treatment. After furnace cooling, the finished sheet-like powder amorphous soft magnetic composite material was obtained.

[0043] The magnetic properties of the products obtained in Example 1, Comparative Example 1, and Comparative Example 2 were tested (1MHz, 10mT), and the results are shown in Table 1.

[0044] Table 1:

[0045] Finished product Effective permeability μe (1MHz, 10mT) Magnetic loss Pcv (kW / m3, 1MHz, 10mT) Quality factor Q (1MHz, 10mT) Example 1 33.9 182.7 57.5 Comparative Example 1 25.6 155.6 60.3 Comparative Example 2 28.4 227.5 52.8

[0046] Combination Figure 1 As can be seen from the photographs of the layered soft magnetic composite material, this invention successfully fabricated an alternating layered structure with a clear boundary between the insulating layer and the magnetically conductive layer. Table 1 shows that, compared to single-component materials, the layered amorphous soft magnetic composite material prepared by this invention exhibits significantly higher permeability than pure spherical powder (Comparative Example 1), while its loss is significantly lower than that of pure sheet-like powder (Comparative Example 2), and its quality factor remains at a high level. This fully demonstrates that the alternating layering design of spherical and sheet-like powder layers produces a synergistic effect, achieving a balance between high permeability and low magnetic loss that cannot be achieved with a single material.

[0047] Example 2

[0048] This embodiment prepares a layered nanocrystalline soft magnetic composite material.

[0049] S1. Preparation of amorphous alloy spherical powder and amorphous alloy flake powder, as detailed below:

[0050] 1a) Preparation of Fe 81 Si2B 16 C1 amorphous spherical powder: Fe prepared by vacuum induction melting 81 Si2B 16 C1 master alloy (vacuum degree better than 0.1 Pa). Subsequently, under an argon protective atmosphere (purity > 99.9%), Fe was obtained by water-gas combined atomization. 81 Si2B 16 C1 amorphous spherical powder with a particle size distribution D50=25.0μm.

[0051] 1b) Preparation of Fe 73.5 Si 13.5 B9Nb3Cu1 non-crystalline powder: Fe prepared by vacuum induction melting 73.5 Si 13.5 B9Nb3Cu1 master alloy (vacuum degree better than 0.1 Pa). Fe was then prepared by single-roll rapid quenching and spinning under an argon protective atmosphere (purity > 99.9%). 73.5 Si 13.5 B9Nb3Cu1 amorphous ribbon. Then Fe... 73.5 Si 13.5 The B9Nb3Cu1 amorphous ribbon was placed in an annealing furnace and subjected to embrittlement heat treatment in a high-purity argon atmosphere. The embrittlement heat treatment temperature was 450℃, the heating rate was 10℃ / min, and the annealing time was 30min. Then, the embrittled Fe... 73.5 Si 13.5 Amorphous B9Nb3Cu1 ribbon was placed in a ball mill with stainless steel grinding balls. The milling speed was 400 r / min, the ball-to-material ratio was 30:1, and the milling medium was anhydrous ethanol. The milling was carried out for 120 min to obtain Fe. 73.5 Si 13.5 B9Nb3Cu1 is a non-crystalline powder with a particle size of 50–240 μm, a thickness of 14–25 μm, and an aspect ratio of 8–15.

[0052] S2. Preparation of cast film:

[0053] 2a) Preparation of spherical powder cast film: 10g of Fe obtained in step S1 was used to prepare the spherical powder cast film. 81 Si2B 16C1 amorphous spherical powder was mixed with 2.8g of polyvinyl butyral (PVB), 0.3g of dibutyl phthalate, 0.03g of dimethyl silicone oil, and 12g of ethanol, and ultrasonically stirred until homogeneous to obtain a casting slurry. The casting slurry was uniformly coated onto a fluoroethylene propylene copolymer (FEP) carrier using a doctor blade. The cast FEP carrier was then placed in a forced-air drying oven to dry, resulting in a spherical powder casting film with a thickness of 100μm.

[0054] 2b) Preparation of sheet-like powder cast film: 20g of Fe obtained in step S1 was used to prepare the film. 73.5 Si 13.5 B9Nb3Cu1 non-crystalline powder was mixed with 2.8g of polyvinyl butyral (PVB), 0.3g of dibutyl phthalate, 0.03g of dimethyl silicone oil, and 20g of ethanol, and ultrasonically stirred to obtain a casting slurry. The casting slurry was then uniformly coated onto a fluoroethylene propylene copolymer (FEP) carrier using a doctor blade. The cast FEP carrier was then dried in a forced-air drying oven to obtain a 100μm thick flake powder casting film.

[0055] S3. Using a punching machine, cut several films with an outer diameter of 12.7 mm and an inner diameter of 7.6 mm from the spherical powder casting film and the sheet powder casting film respectively. Stack them alternately in the order of one spherical powder casting film and one sheet powder casting film, 6 of each, and place them in a mold to form a laminated preform.

[0056] S4. Press the laminated preform into shape by first holding it under 1000MPa pressure for 40s, and then holding it under 1800MPa pressure for 60s to obtain the laminated soft magnetic composite material precursor.

[0057] S5. Place the laminated soft magnetic composite material precursor in a heat treatment furnace, and under an argon protective atmosphere, heat it to 520℃ at a rate of 10℃ / min, hold it at that temperature for 30min for crystallization heat treatment, and then cool it with the furnace to obtain the laminated nanocrystalline soft magnetic composite material product.

[0058] Comparative Example 3

[0059] Using only the spherical powder cast film obtained in step S2 of Example 2, films with an outer diameter of 12.7 mm and an inner diameter of 7.6 mm were cut from the spherical powder cast film, stacked into 12 sheets, and pressed into shape in a mold. The film was held at 1000 MPa for 30 s, then held at 1800 MPa for 60 s to obtain a spherical powder soft magnetic composite material precursor. The spherical powder soft magnetic composite material precursor was placed in a heat treatment furnace and heated to 520°C at a rate of 10°C / min under an argon protective atmosphere, held for 30 min for crystallization heat treatment, and then cooled in the furnace to obtain the finished spherical powder nanocrystalline soft magnetic composite material.

[0060] Comparative Example 4

[0061] Using only the sheet-like powder cast film obtained in step S2 of Example 2, films with an outer diameter of 12.7 mm and an inner diameter of 7.6 mm were cut from the sheet-like powder cast film, stacked into 12 sheets, and pressed into shape in a mold. The film was held at 1000 MPa for 30 s, and then held at 1800 MPa for 60 s to obtain a sheet-like powder soft magnetic composite material precursor. The sheet-like powder soft magnetic composite material precursor was placed in a heat treatment furnace and heated to 520 °C at a rate of 10 °C / min under an argon protective atmosphere, and held for 30 min for crystallization heat treatment. After furnace cooling, the finished sheet-like powder nanocrystalline soft magnetic composite material was obtained.

[0062] The magnetic properties of the products obtained in Example 2, Comparative Example 3, and Comparative Example 4 were tested (1MHz, 10mT), and the results are shown in Table 2.

[0063] Table 2:

[0064] Finished product Effective permeability μe (1MHz, 10mT) Magnetic loss Pcv (kW / m3, 1MHz, 10mT) Quality factor Q (1MHz, 10mT) Example 2 42.4 161.6 59.8 Comparative Example 3 28.8 125.5 65.2 Comparative Example 4 39.4 201.8 55.7

[0065] As shown in Table 2, the results of Example 2 also verify the beneficial effects of the present invention. Compared with single-component materials, the layered nanocrystalline composite material has a much higher magnetic permeability than pure spherical powder materials (Comparative Example 3), while its loss is significantly lower than that of pure sheet powder materials (Comparative Example 4), thus achieving excellent comprehensive performance.

[0066] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of the present invention.

Claims

1. A layered soft magnetic composite material, characterized in that: It includes alternating stacked insulating and magnetic layers, wherein the insulating layers are formed by combining amorphous and / or nanocrystalline soft magnetic alloy spherical powder with an insulating bonding system, and the magnetic layers are formed by combining amorphous and / or nanocrystalline soft magnetic alloy sheet powder with an insulating bonding system.

2. The laminated soft magnetic composite material according to claim 1, characterized in that: The general chemical formula of the amorphous and / or nanocrystalline soft magnetic alloy is: Fe (100-a-b-c-d-e-f-g-h) Co a Ni b Si c B d P e C f Nb g Cu h The atomic percentages satisfy the following conditions: 0≤a≤20.0; 0≤b≤20.0; 2.0≤c≤13.5; 6.0≤d≤9.0; 0≤e≤5.0; 0≤f≤2.0; 0≤g≤3.0; 0≤h≤1.

5.

3. The laminated soft magnetic composite material according to claim 1, characterized in that: The thickness ratio of the insulating layer to the magnetic conductive layer is from 0.2:1 to 5:

1.

4. A method for preparing the laminated soft magnetic composite material as described in any one of claims 1-3, characterized in that, Includes the following steps: S1. Provide amorphous and / or nanocrystalline soft magnetic alloy spherical powder and amorphous and / or nanocrystalline soft magnetic alloy flake powder; S2. Preparation of cast film: The spherical powder is mixed with binder and solvent to form a spherical powder casting slurry, which is then cast and dried to obtain a spherical powder cast film; The sheet powder is mixed with binder and solvent to form a sheet powder casting slurry, which is then cast and dried to obtain a sheet powder cast film. S3. Alternately stack the spherical powder casting film and the sheet-shaped powder casting film to form a laminated preform; S4. The laminated preform is pressed and formed by first holding it under a first pressure P1 for a first time t1, and then holding it under a second pressure P2 greater than P1 for a second time t2 to obtain a composite material precursor. S5. The composite material precursor is subjected to heat treatment to obtain the laminated soft magnetic composite material as described in any one of claims 1 to 3.

5. The method for preparing a layered soft magnetic composite material according to claim 4, characterized in that: In step S4, the first pressure P1 is 400-1000 MPa, and the first time t1 is 5-45 s; the second pressure P2 is 800-2400 MPa, and the second time t2 is 10-90 s.

6. The method for preparing a layered soft magnetic composite material according to claim 4, characterized in that: In step S2, the thickness of the spherical powder casting film and the sheet-shaped powder casting film are each independently 90-500 μm.

7. The method for preparing a layered soft magnetic composite material according to claim 4, characterized in that: The adhesive is at least one of polyvinyl butyral, polyurethane, and silicone resin.

8. The method for preparing a layered soft magnetic composite material according to claim 7, characterized in that: The casting paste also contains a plasticizer, which is at least one of dibutyl phthalate and dimethyl silicone oil.

9. A method for preparing a laminated soft magnetic composite material according to claim 7 or 8, characterized in that: The casting slurry also contains nano-sized silica as an insulating filler.

10. The method for preparing a layered soft magnetic composite material according to claim 4, characterized in that: In step S1, the spherical powder is prepared by atomization; the flake powder is prepared into amorphous and / or nanocrystalline ribbons by melt quenching, and then subjected to embrittlement heat treatment and ball milling.

11. The method for preparing a layered soft magnetic composite material according to claim 10, characterized in that: In the embrittlement heat treatment, the embrittlement heat treatment temperature range is from 200°C below the crystallization temperature of amorphous and / or nanocrystalline materials to their crystallization temperature, and the embrittlement heat treatment time is 30 to 240 minutes.

12. The method for preparing a layered soft magnetic composite material according to claim 10, characterized in that: In the ball mill, the ball-to-material ratio is 20:1 to 50:

1.

13. The method for preparing a layered soft magnetic composite material according to claim 4, characterized in that: The obtained laminated soft magnetic composite material was tested at a frequency of 1MHz and a magnetic flux density of 10mT. The effective permeability μe≥30, the magnetic loss Pcv≤200kW / m³, and the quality factor Q≥55.

14. An electronic component, characterized in that: It comprises a laminated soft magnetic composite material as described in any one of claims 1 to 3.

Images