Alloy material for inductor and preparation method therefor, and inductor

Abstract

An alloy material for an inductor. The particles of the alloy material are of a core-shell structure, wherein the shell is attached to the outer surface of the core, the core is an FeSiCr alloy particle, and the shell is a Cr2O3 layer. The median particle size D50 of the particles of the alloy material and the thickness T of the Cr2O3 layer satisfy the following relationship: when D50 is greater than or equal 3 μm and less than or equal to 5 μm, the percentage of T relative to D50 is greater than or equal to 0.98% and less than or equal to 2.49%; when D50 is greater than or equal 5 μm and less than or equal to 10 μm, the percentage of T relative to D50 is greater than 2.49% and less than or equal to 3.95%; and when D50 is greater than or equal 10 μm and less than or equal to 25 μm, the percentage of T relative to D50 is greater than 3.95% and less than or equal to 8.56%. The magnetic permeability and the insulation withstand voltage of the alloy material achieve a favorable balance, thereby improving the comprehensive performance of an inductor. The present application also relates to a preparation method for an alloy material for an inductor, and an inductor.

Description

An alloy material for inductors, its preparation method, and an inductor. Technical Field

[0001] This invention relates to the field of inductors, and in particular to an alloy material for inductors, a method for preparing the same, and an inductor. Background Technology

[0002] Currently, alloy materials used in power inductors often fail to achieve their theoretical performance values. In existing technologies, the insulation coating of most alloy materials is achieved through the following methods: 1. Coating the surface of alloy particles with an organic resin material to form an insulating layer. However, resin materials have poor thermal stability and are prone to decomposition or softening at high temperatures, affecting the insulation effect of the magnetic core. Furthermore, increasing the thickness of the resin material leads to a decrease in the inductance performance of the magnetic core, and uneven coating affects the tight packing between particles, resulting in performance degradation. 2. Generating an inorganic oxide film (such as SiO2, Al2O3, etc.) on the surface of alloy particles using chemical or physical methods to enhance insulation. This process is complex and easily leads to increased costs. 3. Coating alloy powders of different particle sizes before mixing and sintering to form a multilayer structure for insulation. This method is prone to oxide layer cracking or detachment during sintering, affecting the insulation effect, and the multilayer coating increases the difficulty and cost of sintering. Existing alloy materials for inductors suffer from insufficient balance between insulation withstand voltage and magnetic permeability.

[0003] It should be noted that the information disclosed in the background section above is only for understanding the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides an alloy material for inductors, a method for preparing the same, and an inductor.

[0005] The present invention adopts the following technical solution:

[0006] In a first aspect, an alloy material for inductors is provided, wherein the alloy material particles have a core-shell structure, the shell being attached to the outer surface of the core, the core being FeSiCr alloy particles, and the shell being a Cr2O3 layer, wherein the median particle size D50 of the alloy material particles and the thickness T of the Cr2O3 layer satisfy the following relationship: when 3μm≤D50<5μm, 0.98%≤T as a percentage of D50≤2.49%; when 5μm≤D50<10μm, 2.49%<T as a percentage of D50≤3.95%; and when 10μm≤D50<25μm, 3.95%<T as a percentage of D50≤8.56%.

[0007] In a second aspect, a method for preparing the alloy material for inductors described in the first aspect is provided, comprising the following steps:

[0008] (1) Using FeSiCr alloy powder as raw material, the surface of the powder is cleaned to remove the naturally oxidized part of the powder surface;

[0009] (2) Under an inert atmosphere containing oxygen, the FeSiCr alloy powder cleaned in step (1) is sintered to generate a Cr2O3 layer on the surface of the particles, thereby obtaining the inductor alloy material. The median particle size D50 of the inductor alloy material is in the range of 3 to 25 μm.

[0010] Thirdly, an inductor is provided, comprising the alloy material for inductors described in the first aspect.

[0011] The present invention has the following beneficial effects: It solves the problem of insufficient balance between insulation withstand voltage and magnetic permeability in existing inductor alloy materials. By controlling the ratio of the median particle size D50 of the alloy material to the thickness T of the Cr2O3 layer, the magnetic permeability of the alloy material is made closer to the theoretical value, while simultaneously possessing excellent insulation withstand voltage. The present invention achieves a better balance between the magnetic permeability and insulation withstand voltage of the alloy material, thus improving the overall performance of the inductor. Attached Figure Description

[0012] Figure 1 is a scanning electron microscope image of the alloy material in Example 1 of the present invention;

[0013] Figure 2 is a scanning electron microscope image of the alloy material in Example 2 of the present invention. Detailed Implementation

[0014] The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present invention. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0015] This invention provides an alloy material for inductors. The alloy material has a core-shell structure, with the shell attached to the outer surface of the core. The core is an FeSiCr alloy particle, and the shell is a Cr2O3 layer. The median particle size D50 of the alloy material and the thickness T of the Cr2O3 layer satisfy the following relationship: when 3μm ≤ D50 < 5μm, 0.98% ≤ T as a percentage of D50 ≤ 2.49%; when 5μm ≤ D50 < 10μm, 2.49% < T as a percentage of D50 ≤ 3.95%; when 10μm ≤ D50 < 25μm, 3.95% < T as a percentage of D50 ≤ 8.56%.

[0016] In some embodiments, when the median particle size D50 of the alloy material is 3.04 μm, the percentage of T in D50 is in the range of 0.99% to 1.64%; when the median particle size D50 of the alloy material is 5.14 μm, the percentage of T in D50 is in the range of 2.53% to 2.92%; when the median particle size D50 of the alloy material is 10.50 μm, the percentage of T in D50 is in the range of 4.29% to 5.24%; and when the median particle size D50 of the alloy material is 21.7 μm, the percentage of T in D50 is in the range of 7.14% to 8.53%.

[0017] The present invention also provides a method for preparing the aforementioned alloy material for inductors, comprising the following steps:

[0018] (1) Using FeSiCr alloy powder as raw material, the surface of the powder is cleaned to remove the naturally oxidized part of the powder surface;

[0019] (2) Under an inert atmosphere containing oxygen, the FeSiCr alloy powder cleaned in step (1) is sintered to generate a Cr2O3 layer on the surface of the particles, thereby obtaining the inductor alloy material. The median particle size D50 of the inductor alloy material is in the range of 3 to 25 μm.

[0020] By directly sintering FeSiCr alloy powder to form a dense Cr2O3 layer on its surface, the insulation performance of the material can be effectively improved, and the following advantages are available: the sintered Cr2O3 oxide layer is dense and uniform, exhibiting high thermal stability; the direct formation of the oxide layer on the particle surface avoids the structural complexity of traditional coatings, resulting in tighter particle packing, a uniform packing structure, and reduced air gaps; compared to other coating methods, the process flow of this invention is simpler, helping to reduce production costs and improve the stability of the production process; furthermore, this invention controls the thickness of the Cr2O3 layer during sintering, thereby controlling the relationship between the median particle size D50 of the alloy material and the thickness T of the Cr2O3 layer. The proportional relationship satisfies the following: when 3μm≤D50<5μm, 0.98%≤T as a percentage of D50≤2.49%; when 5μm≤D50<10μm, 2.49%<T as a percentage of D50≤3.95%; when 10μm≤D50<25μm, 3.95%<T as a percentage of D50≤8.56%. This makes the electric field distribution inside the alloy material more uniform, and achieves a better balance between permeability and insulation withstand voltage, thus improving the overall performance of the inductor. If the proportional relationship between the median particle size D50 of the alloy material and the thickness T of the Cr2O3 layer is not within the above range, the insulation withstand voltage performance and permeability of the inductor will be difficult to improve simultaneously, which will affect the performance of the power inductor.

[0021] It is worth noting that during the sintering process, due to uneven powder distribution or local temperature differences, some alloy particles may not have a sufficient Cr2O3 layer formed on their surface. This local non-uniformity is unavoidable at the microscopic scale. Considering the errors in the actual process, it is expected that no more than 10 wt% of alloy particles will have this situation. This deviation is within the common error range in the manufacturing process and will not significantly affect the overall performance of the material.

[0022] In some implementations, the cleaning in step (1) refers to cleaning the surface of the powder with an inert gas.

[0023] In some embodiments, in step (2), the thickness of the Cr2O3 layer is controlled by controlling at least one of the sintering temperature, sintering time, and oxygen concentration in the inert atmosphere, thereby controlling the ratio between the median particle size D50 of the alloy material particles and the thickness T of the Cr2O3 layer.

[0024] In some embodiments, in step (2), the sintering temperature is 750-880℃ (preferably 800-880℃), the sintering time is 0.5-3h, and the oxygen concentration in the inert atmosphere is 21 vol% to 50 vol%.

[0025] In some embodiments, the inert atmosphere containing oxygen contains oxygen, and also contains at least one of nitrogen and argon.

[0026] In some embodiments, the Cr content in the FeSiCr alloy powder in step (1) is ≥2wt%; preferably, in step (1), the Cr content in the FeSiCr alloy powder is ≥2wt% and ≤4wt%.

[0027] In some embodiments, the FeSiCr alloy powder in step (1) contains 91.5wt%-93.5% Fe, 4.5wt% Si and 2.0wt%-4.0wt% Cr.

[0028] In some embodiments, in step (1), the FeSiCr alloy powder contains 91.5 wt% Fe, 4.5 wt% Si and 4.0 wt% Cr; or the FeSiCr alloy powder contains 92.5 wt% Fe, 4.5 wt% Si and 3.0 wt% Cr; or the FeSiCr alloy powder contains 93.5 wt% Fe, 4.5 wt% Si and 2.0 wt% Cr.

[0029] In some embodiments, the particle size distribution D50 of the FeSiCr alloy powder in step (1) is in the range of 2 to 20 μm.

[0030] A specific embodiment of the present invention also provides an inductor, which includes the aforementioned alloy material for inductors.

[0031] The following describes specific embodiments of the present invention.

[0032] Example 1

[0033] The preparation method of alloy materials includes the following steps:

[0034] 1. Select FeSiCr alloy powder with a median particle size distribution (D'50) of 3 μm (mass percentages of each component are as follows: Fe 91.5%, Si 4.5%, Cr 4.0%) to ensure uniform particle distribution and reduce the influence of fine particle impurities. Use inert gas to clean the powder surface to remove naturally oxidized portions, ensuring the uniformity and consistency of the Cr2O3 layer formed by oxidation.

[0035] 2. Under a nitrogen atmosphere, the cleaned FeSiCr alloy powder was heated to 800℃ in an environment with an oxygen volume fraction of 30 vol%, at a heating rate of 5℃ / min, and held at that temperature for 1 hour (i.e., the sintering and oxidation time was 1 hour). After natural cooling to room temperature, an alloy material with a median particle size D50 of 3.04 μm and a Cr2O3 layer thickness T of 30-50 nm was obtained. As shown in Figure 1, scanning electron microscopy analysis and measurement revealed that the Cr2O3 layer was uniform and smooth, with a thickness of 30-50 nm, and the percentage of the Cr2O3 layer thickness T to D50 ranged from 0.99% to 1.64%.

[0036] 3. Add an appropriate amount of binder to the alloy material obtained in step 2, place it into an 8×5×2mm mold, and apply a pressure of 900MPa to press the powder into shape. Place the pressed magnetic ring into a sintering mold, keep it sealed, introduce inert gas, and perform sintering treatment. The sintering temperature is controlled at 850℃ for 9 hours. This sintering temperature ensures that the Cr2O3 insulating layer between particles is not damaged during the sintering process and helps to form a stable interfacial bond between particles, resulting in higher core density.

[0037] 4. The performance of the molded magnetic ring was tested, and the test results are shown in Table 1.

[0038] Comparative Example 1

[0039] The difference from Example 1 is that the sintering oxidation time in step 2 is 20 min. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 1 was 10-20 nm, the median particle size D50 of the alloy material was 3.01 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 0.33% to 0.66%. Other steps were the same as in Example 1. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 1, and the test results are shown in Table 1.

[0040] Comparative Example 2

[0041] The difference from Example 1 is that the sintering oxidation time in step 2 is 5 hours. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 2 was 100-120 nm, the median particle size D50 of the alloy material was 3.11 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 3.22% to 3.86%. Other steps were the same as in Example 1. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 2, and the test results are shown in Table 1.

[0042] Table 1:

[0043] As shown in Table 1, the sample of Example 1 has a permeability of 110, an insulation resistance of 1800 MΩ, and a withstand voltage of 1401 V. The permeability is close to 92% of the theoretical value (the theoretical permeability of the material in this example is 120). Under the condition of meeting the insulation and withstand voltage requirements, the permeability of the sample of Example 1 is closer to the theoretical value. In contrast, the insulation and withstand voltage of the sample of Comparative Example 1 are poor, and the permeability of Comparative Example 2 is low. Therefore, Example 1 achieves excellent insulation and a good permeability value, meeting the design requirements.

[0044] Example 2

[0045] The preparation method of alloy materials includes the following steps:

[0046] 1. Select FeSiCr alloy powder with a particle size distribution (median particle size) D'50 = 5 μm. The mass percentage of each component in the alloy powder and the pretreatment are the same as in Example 1.

[0047] 2. The difference from step 2 of Example 1 is that the sintering oxidation temperature was set to 850℃ and the sintering oxidation time was set to 1.5 hours, resulting in an alloy material with a median particle size D50 of 5.14 μm and a Cr2O3 layer thickness T of 130-150 nm. As shown in Figure 2, the Cr2O3 layer thickness was measured using a scanning electron microscope. The Cr2O3 layer was uniform and flat, with a thickness of 130-150 nm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 2.53% to 2.92%.

[0048] 3. The difference from step 3 of Example 1 is that the alloy material obtained in step 2 is pressed and sintered at a temperature of 870°C for 9 hours.

[0049] 4. The formed magnetic ring was tested, and the test results are shown in Table 2.

[0050] Comparative Example 3

[0051] The difference from Example 2 is that the sintering oxidation time in step 2 is 20 min. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 3 was 20-40 nm, the median particle size D50 of the alloy material was 5.03 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 0.40% to 0.80%. Other steps were the same as in Example 2. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 3, and the test results are shown in Table 2.

[0052] Comparative Example 4

[0053] The difference from Example 2 is that the sintering oxidation time in step 2 was 5 hours. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 4 was 210-230 nm, the median particle size D50 of the alloy material was 5.22 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 4.02% to 4.41%. Other steps were the same as in Example 2. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 4, and the test results are shown in Table 2.

[0054] Table 2:

[0055] As shown in Table 2, the sample of Example 2 has a permeability of 10⁴ and a withstand voltage of 1969V. The permeability is close to 87% of the theoretical value (the theoretical permeability of the material in this example is 120). The sample of Example 2, while meeting the insulation withstand voltage requirements, has a permeability closer to the theoretical value. In contrast, the sample of Comparative Example 3 has poor insulation withstand voltage, and the sample of Comparative Example 4 has a lower permeability. Therefore, Example 2 achieves a good balance between insulation and permeability, ensuring the stability and withstand voltage performance of the product under operating conditions.

[0056] Example 3

[0057] The preparation method of alloy materials includes the following steps:

[0058] 1. Select FeSiCr alloy powder with a particle size distribution (median particle size) D'50 = 10 μm. The mass percentage of each component in the alloy powder and the pretreatment are the same as in Example 1.

[0059] 2. The difference from step 2 of Example 1 is that the sintering oxidation temperature is set to 850℃ and the sintering oxidation time is set to 2 hours, resulting in an alloy material with a median particle size D50 of 10.50μm and a Cr2O3 layer thickness T of 450-550nm. The percentage of the Cr2O3 layer thickness T to D50 is in the range of 4.29% to 5.24%.

[0060] 3. The difference from step 3 of Example 1 is that the alloy material obtained in step 2 is pressed and sintered at a temperature of 870°C for 9 hours.

[0061] 4. The formed magnetic ring was tested, and the test results are shown in Table 3.

[0062] Comparative Example 5

[0063] The difference from Example 3 is that the sintering oxidation time in step 2 was 27 min. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 5 was 150-250 nm, the median particle size D50 of the alloy material was 10.20 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 1.47% to 2.45%. Other steps were the same as in Example 3. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 5, and the test results are shown in Table 3.

[0064] Comparative Example 6

[0065] The difference from Example 3 is that the sintering oxidation time in step 2 was 6 hours. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 6 was 950-1050 nm, the median particle size D50 of the alloy material was 11.00 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 8.64% to 9.55%. Other steps were the same as in Example 3. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 6, and the test results are shown in Table 3.

[0066] Table 3:

[0067] As shown in Table 3, Example 3 achieves a good balance between insulation and magnetic permeability, ensuring the stability and pressure resistance of the product under working conditions.

[0068] Example 4

[0069] The preparation method of alloy materials includes the following steps:

[0070] 1. Select FeSiCr alloy powder with a particle size distribution (median particle size) D'50 = 20 μm. The mass percentage of each component in the alloy powder and the pretreatment are the same as in Example 1.

[0071] 2. The difference from step 2 of Example 1 is that the sintering oxidation temperature is set to 880℃ and the sintering oxidation time is set to 3 hours, resulting in an alloy material with a median particle size D50 of 21.7μm and a Cr2O3 layer thickness T of 1550-1850nm. The percentage of the Cr2O3 layer thickness T to D50 is in the range of 7.14% to 8.53%.

[0072] 3. The difference from step 3 of Example 1 is that the alloy material obtained in step 2 is pressed and sintered at a temperature of 870°C for 9 hours.

[0073] 4. The formed magnetic ring was tested, and the test results are shown in Table 4.

[0074] Comparative Example 7

[0075] The difference from Example 4 is that the sintering oxidation time in step 2 was 25 min. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 7 was 300-500 nm, the median particle size D50 of the alloy material was 20.4 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 1.47% to 2.45%. Other steps were the same as in Example 4. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 7, and the test results are shown in Table 4.

[0076] Comparative Example 8

[0077] The difference from Example 4 is that the sintering oxidation time in step 2 was 6 hours. Scanning electron microscopy analysis and measurement showed that the thickness of the Cr2O3 layer on the surface of the alloy material obtained in Comparative Example 8 was 2400-2700 nm, the median particle size D50 of the alloy material was 22.5 μm, and the percentage of the Cr2O3 layer thickness T to D50 was in the range of 10.67% to 12.00%. Other steps were the same as in Example 4. Performance tests were performed on the magnetic ring formed using the alloy material of Comparative Example 8, and the test results are shown in Table 4.

[0078] Table 4:

[0079] As shown in Table 4, Example 4 achieves a good balance between insulation and magnetic permeability, ensuring the stability and pressure resistance of the product under working conditions.

[0080] The above embodiments optimize the magnetic permeability and insulation withstand voltage of the alloy material by adjusting the ratio of the median particle size D50 of the alloy material to the thickness T of the Cr2O3 layer through adjusting the thickness of the Cr2O3 layer. Therefore, the alloy material of the present invention has a simple preparation process, higher stability, durability and electrical performance, and has high market competitiveness and application value.

[0081] The above description provides a further detailed explanation of the present invention in conjunction with specific / preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. An alloy material for inductors, characterized in that, The alloy material particles have a core-shell structure, with the shell attached to the outer surface of the core. The core is an FeSiCr alloy particle, and the shell is a Cr2O3 layer. The median particle size D50 of the alloy material particles and the thickness T of the Cr2O3 layer satisfy the following relationship: when 3μm ≤ D50 < 5μm, 0.98% ≤ T as a percentage of D50 ≤ 2.49%; when 5μm ≤ D50 < 10μm, 2.49% < T as a percentage of D50 ≤ 3.95%; when 10μm ≤ D50 < 25μm, 3.95% < T as a percentage of D50 ≤ 8.56%.

2. The alloy material for inductors as described in claim 1, characterized in that, When the median particle size D50 of the alloy material is 3.04 μm, the percentage of T in D50 is in the range of 0.99% to 1.64%; when the median particle size D50 of the alloy material is 5.14 μm, the percentage of T in D50 is in the range of 2.53% to 2.92%; when the median particle size D50 of the alloy material is 10.50 μm, the percentage of T in D50 is in the range of 4.29% to 5.24%; and when the median particle size D50 of the alloy material is 21.7 μm, the percentage of T in D50 is in the range of 7.14% to 8.53%.

3. A method for preparing an alloy material for inductors according to any one of claims 1-2, characterized in that, Includes the following steps: (1) Using FeSiCr alloy powder as raw material, the surface of the powder is cleaned to remove the naturally oxidized part of the powder surface; (2) Under an inert atmosphere containing oxygen, the FeSiCr alloy powder cleaned in step (1) is sintered to generate a Cr2O3 layer on the surface of the particles, thereby obtaining the inductor alloy material. The median particle size D50 of the inductor alloy material is in the range of 3 to 25 μm.

4. The preparation method according to claim 3, characterized in that, In step (2), the thickness of the Cr2O3 layer is controlled by controlling at least one of the sintering temperature, sintering time, and oxygen concentration in the inert atmosphere, thereby controlling the ratio between the median particle size D50 of the alloy material particles and the thickness T of the Cr2O3 layer.

5. The preparation method according to claim 4, characterized in that, In step (2), the sintering temperature is 750-880℃, the sintering time is 0.5-3h, and the oxygen concentration in the inert atmosphere is 21 vol% to 50 vol%.

6. The preparation method according to claim 3, characterized in that, The Cr content in the FeSiCr alloy powder of step (1) is ≥2wt%.

7. The preparation method according to claim 3, characterized in that, In step (1), the Cr content in the FeSiCr alloy powder is ≥2wt% and ≤4wt%.

8. The preparation method according to claim 3, characterized in that, The FeSiCr alloy powder in step (1) contains 91.5wt%-93.5% Fe, 4.5wt% Si and 2.0wt%-4.0wt% Cr.

9. The preparation method according to claim 8, characterized in that, In step (1), the FeSiCr alloy powder contains 91.5 wt% Fe, 4.5 wt% Si and 4.0 wt% Cr; or the FeSiCr alloy powder contains 92.5 wt% Fe, 4.5 wt% Si and 3.0 wt% Cr; or the FeSiCr alloy powder contains 93.5 wt% Fe, 4.5 wt% Si and 2.0 wt% Cr.

10. The preparation method according to claim 3, characterized in that, The median particle size D50 of the FeSiCr alloy powder in step (1) is in the range of 2 to 20 μm.

11. An inductor, characterized in that, It includes the alloy material for inductors as described in any one of claims 1-2.

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