Soft magnetic alloy and method for producing the same

Abstract

The application relates to the technical field of soft magnetic alloy, in particular to a soft magnetic alloy and a preparation method thereof. The preparation method comprises the following steps: providing a soft magnetic alloy blank; performing plastic deformation treatment on the soft magnetic alloy blank to obtain a plastic deformation piece; and performing post-treatment on the plastic deformation piece, wherein the post-treatment comprises at least one electric pulse treatment and at least one annealing heat treatment, so as to obtain the soft magnetic alloy. According to the method, plastic deformation is performed on the soft magnetic alloy blank, electric pulse treatment and annealing heat treatment are performed on the plastic deformation piece, and the synergy of the two energy fields can significantly improve the yield strength and elongation of the obtained soft magnetic alloy, effectively reduce the coercive force of the soft magnetic alloy, and make the soft magnetic alloy have excellent strength, excellent toughness and excellent magnetism.

Description

Technical Field

[0001] This application relates to the field of soft magnetic alloy technology, and in particular to a soft magnetic alloy and its preparation method. Background Technology

[0002] Soft magnetic alloys, due to their extremely high saturation magnetic induction, are core materials for advanced equipment such as aerospace and precision motors. However, there is a significant contradiction between the strength, toughness, and magnetism of these alloys. To obtain high strength and hardness, it is usually necessary to strengthen soft magnetic alloys with B2 ordered phases and precipitates, but this often leads to a sharp decrease in the plasticity and toughness of the soft magnetic alloys.

[0003] To improve the plasticity and magnetism of soft magnetic alloys, only conventional high-temperature annealing or solution treatment can be performed. However, this leads to coarse grains and a significant reduction in strength. Therefore, current processes cannot achieve a balance between strength, plasticity, and magnetic properties in soft magnetic alloys, which severely restricts their application in higher-performance scenarios.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of protection of this application. Summary of the Invention

[0005] This application provides a soft magnetic alloy and a method for preparing the same, in order to solve or alleviate one or more of the technical problems mentioned above.

[0006] A first aspect of this application provides a method for preparing a soft magnetic alloy, comprising the following steps:

[0007] A soft magnetic alloy billet is provided, wherein the soft magnetic alloy billet comprises 49%-51% cobalt, 0.8%-1.8% vanadium, no more than 0.04% carbon, no more than 0.3% manganese, no more than 0.3% silicon, no more than 0.02% phosphorus, no more than 0.02% sulfur, no more than 0.02% copper, and no more than 0.05% nickel, with the balance being iron and unavoidable impurities;

[0008] The soft magnetic alloy blank is subjected to plastic deformation treatment to obtain a plastically deformed part;

[0009] The plastically deformed part is subjected to post-processing, which includes at least one electrical pulse treatment and at least one annealing heat treatment to obtain the soft magnetic alloy.

[0010] The preparation method of this application involves plastic deformation of the soft magnetic alloy billet, at least one electrical pulse treatment of the plastically deformed part, and at least one annealing heat treatment. The synergistic effect of these two energy fields significantly improves the yield strength and elongation of the soft magnetic alloy while effectively reducing its coercivity, ultimately resulting in a soft magnetic alloy with excellent strength, toughness, and magnetism. This method is highly efficient and energy-saving. The electrical pulse treatment concentrates energy on the material bulk, has a short treatment time, and shortens the annealing heat treatment time. The current during the electrical pulse treatment promotes dislocation movement and annihilation in the material. Combined with the thermal diffusion effect of the annealing heat treatment, it allows for precise control of recrystallization degree, grain size, and second-phase precipitation behavior, thereby obtaining a fine, uniform, and ideal microstructure, enabling the soft magnetic alloy to exhibit high strength, high plasticity, and low coercivity.

[0011] According to an embodiment of this application, the plastic deformation treatment includes warm rolling. Before warm rolling, the soft magnetic alloy billet is held at 600℃-800℃ for 10-60 minutes, and the reduction rate of the warm rolling is 55%-75%. This further promotes the formation of a soft magnetic alloy with both high strength, high plasticity, and low coercivity.

[0012] According to an embodiment of this application, the plastic deformation treatment includes cold rolling, the cold rolling process comprising: cold rolling the soft magnetic alloy billet at room temperature, wherein the cold rolling reduction rate is 50%-85%. This further promotes the resulting soft magnetic alloy to possess both high strength, high plasticity, and low coercivity.

[0013] According to an embodiment of this application, the post-processing is as follows: first, the electrical pulse treatment is performed, and then the product obtained from the electrical pulse treatment is subjected to the annealing heat treatment.

[0014] According to an embodiment of this application, the post-processing is as follows: first, the annealing heat treatment is performed, then the product obtained from the annealing heat treatment is cooled to room temperature, and then the cooled intermediate is subjected to the electrical pulse treatment.

[0015] According to an embodiment of this application, the post-processing is as follows: first, the first electrical pulse treatment is performed, then the product obtained from the electrical pulse treatment is subjected to the annealing heat treatment, then the product obtained from the annealing heat treatment is cooled to room temperature, and then the cooled intermediate is subjected to the second electrical pulse treatment.

[0016] According to embodiments of this application, the post-processing is performed cyclically, wherein the number of cycles is at least two. Thus, multiple cycles can facilitate the formation of hierarchical nanostructures in soft magnetic alloys.

[0017] According to an embodiment of this application, the conditions for the electrical pulse processing are: a current density of 50 A / mm². 2 -300A / mm 2 The time range is 0.1s-60s; the frequency range is 50Hz-1000Hz.

[0018] According to an embodiment of this application, the annealing heat treatment includes: heating to 500°C-950°C in a hydrogen atmosphere at a heating rate of 5°C / min-15°C / min, and holding at that temperature for 10 min-4 h.

[0019] A second aspect of this application provides a soft magnetic alloy, which is prepared using the preparation method described in the first aspect. The soft magnetic alloy has a grain size of 5μm-20μm, a yield strength of not less than 800MPa, an elongation of not less than 10%, and a coercivity of not more than 80A / m. Attached Figure Description

[0020] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0021] Figure 1 These are process flow diagrams for the preparation of soft magnetic alloys in some embodiments;

[0022] Figure 2 This is the EBSD grain orientation diagram of the soft magnetic alloy in Example 1;

[0023] Figure 3 This is the EBSD grain orientation diagram of the soft magnetic alloy in Comparative Example 1;

[0024] Figure 4 This is a TEM image of the soft magnetic alloy in Example 3. Detailed Implementation

[0025] The embodiments of this application are described in detail below. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0026] It should be noted that the terms "comprising" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, etc., that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products, etc.

[0027] In this application, when numerical intervals (i.e., numerical ranges) are involved, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include percentage intervals, ratio intervals, proportion intervals, etc.

[0028] Heat treatment of soft magnetic alloys often employs a single process: solution treatment, aging, or stress-relief annealing. For example, a two-step process of high-temperature solution quenching followed by low-temperature aging can, to some extent, balance the plasticity and magnetism of soft magnetic alloys, but it suffers from long processing times, limited precision in microstructure control, and unstable improvement in plasticity. Particularly for cold-rolled hardened strips, conventional annealing requires a long time to complete recrystallization and stress relief, and it is difficult to avoid excessive precipitation of harmful ordered phases. For instance, cold-rolled 1J22 alloy (soft magnetic alloy billet) contains high-density dislocations and work-hardened structures. While a single traditional annealing process can achieve recrystallization and stress relief, it often suffers from long processing times, high energy consumption, and difficulty in precisely controlling the morphology and distribution of the B2 ordered phase and Laves precipitates; the grains are prone to coarsening, leading to strength loss in the soft magnetic alloy. If lower-temperature annealing is used to maintain strength, recrystallization is insufficient, resulting in limited improvement in plasticity and magnetism. This makes it difficult for soft magnetic alloys to achieve simultaneous improvement in both magnetic properties and plasticity.

[0029] Accordingly, a first aspect of the embodiments of this application provides a method for preparing a soft magnetic alloy. (See reference...) Figure 1 The preparation method includes the following steps:

[0030] A soft magnetic alloy billet is provided, wherein the soft magnetic alloy billet comprises 49%-51% cobalt, 0.8%-1.8% vanadium, no more than 0.04% carbon, no more than 0.3% manganese, no more than 0.3% silicon, no more than 0.02% phosphorus, no more than 0.02% sulfur, no more than 0.02% copper, and no more than 0.05% nickel, with the balance being iron and unavoidable impurities;

[0031] The soft magnetic alloy blank is subjected to plastic deformation treatment to obtain a plastically deformed part;

[0032] The plastically deformed part is subjected to post-processing, which includes at least one electrical pulse treatment and at least one annealing heat treatment to obtain the soft magnetic alloy.

[0033] The preparation method of this application involves plastic deformation of the soft magnetic alloy billet, at least one electrical pulse treatment of the plastically deformed part, and at least one annealing heat treatment. The synergistic effect of these two energy fields significantly improves the yield strength and elongation of the soft magnetic alloy while effectively reducing its coercivity, ultimately giving the soft magnetic alloy excellent strength, excellent toughness, and excellent magnetic properties. This method is highly efficient and energy-saving. The electrical pulse treatment concentrates energy on the material bulk, has a short treatment time, and can also shorten the annealing heat treatment time. The current during the electrical pulse treatment promotes dislocation movement and annihilation in the material. Combined with the thermal diffusion effect of the annealing heat treatment, it allows for precise control of the degree of recrystallization, grain size, and second-phase precipitation behavior, thereby obtaining a fine, uniform, and ideal microstructure, enabling the soft magnetic alloy to exhibit excellent magnetic properties, excellent strength, and excellent plasticity.

[0034] According to an embodiment of this application, step (1) involves providing a soft magnetic alloy billet. In this step, the soft magnetic alloy billet comprises 49%-51% cobalt, 0.8%-1.8% vanadium, no more than 0.04% carbon, no more than 0.3% manganese, no more than 0.3% silicon, no more than 0.02% phosphorus, no more than 0.02% sulfur, no more than 0.02% copper, and no more than 0.05% nickel, with the balance being iron and unavoidable impurities. Such alloys often struggle to simultaneously improve both plasticity and magnetism. The method of this application addresses the unique performance contradictions of this type of alloy by employing electric pulse and annealing heat treatment. Through the temporal coupling of the two energy fields, a microstructure with fine and uniform grains and ideal precipitate distribution is obtained with a shorter cycle and lower energy consumption. This allows the soft magnetic alloy to simultaneously exhibit higher strength, higher plasticity, and lower coercivity.

[0035] According to an embodiment of this application, step (2) involves subjecting the soft magnetic alloy billet to plastic deformation treatment to obtain a plastically deformed part. In this step, plastic deformation is the driving force for enhancing recrystallization during subsequent post-processing.

[0036] In some embodiments, the plastic deformation treatment includes cold rolling. Cold rolling can introduce high-density dislocations into the soft magnetic alloy billet.

[0037] Furthermore, the cold rolling process includes: cold rolling the soft magnetic alloy billet at room temperature, wherein the cold rolling reduction rate is 50%-85%. This further promotes the obtaining of a soft magnetic alloy that possesses excellent strength, excellent toughness, and excellent magnetic properties.

[0038] In some embodiments, the plastic deformation treatment includes warm rolling. Warm rolling can form a unique transitional structure within the soft magnetic alloy billet, possessing both high dislocation energy storage and clear subgrain boundaries. This structure is an ideal precursor for subsequently obtaining a fine and uniform recrystallized structure.

[0039] Furthermore, before the warm rolling, the soft magnetic alloy billet is held at 600℃-800℃ for 10-60 minutes, and the reduction rate of the warm rolling is 55%-75%. This further promotes the obtaining of a soft magnetic alloy with excellent strength, excellent toughness, and excellent magnetic properties.

[0040] As a specific example, the thickness of the soft magnetic alloy billet is 0.02 mm to 2.00 mm. The soft magnetic alloy billet is then warm-rolled, and before warm rolling, it is held at 600°C to 800°C for 10 to 60 minutes. After plastic deformation, the soft magnetic alloy billet forms an intermediate part with a thickness of 0.005 mm to 0.9 mm.

[0041] According to an embodiment of this application, step (3) involves post-processing the plastically deformed part, the post-processing including at least one pulse treatment and at least one annealing heat treatment to obtain the soft magnetic alloy.

[0042] In some embodiments, the post-processing involves first performing the electrical pulse treatment, and then subjecting the product obtained from the electrical pulse treatment to the annealing heat treatment. This sequential processing helps to obtain fine, uniform equiaxed recrystallized grains, avoiding grain coarsening or abnormal growth that may result from traditional long-term annealing, thereby improving the strength and magnetism of the soft magnetic alloy.

[0043] In some embodiments, the post-processing involves: first performing the annealing heat treatment, then cooling the annealed material to room temperature, and finally performing the electrical pulse treatment on the cooled intermediate. This sequential approach to processing the plastically treated material helps to first establish a stable and uniform baseline microstructure through annealing, then precisely control the microstructure established during the annealing heat treatment process using electrical pulses, and then selectively and non-equilibrium fine-tuning the microstructure. This allows for optimization of the microstructure interface state and redistribution of defects, ultimately resulting in a soft magnetic alloy with both superior strength and superior magnetic properties.

[0044] In some embodiments, the post-processing involves first performing the first electrical pulse treatment, followed by annealing heat treatment on the electrical pulse treatment result, then cooling the annealed heat treatment result to room temperature, and finally performing a second electrical pulse treatment on the cooled intermediate part. This sequence of electrical pulse treatment-annealing heat treatment-electrical pulse treatment allows the initial electrical pulse treatment to rapidly activate defects in the deformed structure and create numerous uniform, highly active nucleation sites; the annealing heat treatment drives recrystallization of the electrical pulse treatment result, thereby obtaining an ultrafine, uniform equiaxed grain structure; and the second electrical pulse treatment on the cooled intermediate part allows the instantaneous energy to suppress rapid grain boundary migration, freezing the fine grain size through interface effects, preventing subsequent grain coarsening, and ultimately obtaining a soft magnetic alloy with both superior strength and superior magnetic properties.

[0045] In some embodiments, the post-processing can be performed cyclically, wherein the number of cycles is at least 2, such as 2, 3, 4, 5, 6, etc. Multiple cycles can help form multi-level nanostructures in soft magnetic alloys, i.e., large-angle grain boundaries segmenting micron or submicron grains, and within the grains, small-angle grain boundaries or dislocation walls segmenting nanoscale cellular structures. This structure can simultaneously contribute ultra-high strength and good toughness to the soft magnetic alloy.

[0046] Furthermore, the current density of the electrical pulse treatment is 50 A / mm. 2 -300A / mm 2 For example, 50A / mm 2 100A / mm 2 200A / mm 2 250A / mm 2 300A / mm 2 wait.

[0047] Furthermore, the duration of the electrical pulse processing is 0.1s-60s, for example, 0.1s, 2s, 10s, 30s, 40s, 50s, 60s, etc.

[0048] Furthermore, the frequency of the electrical pulse processing is 50Hz-1000Hz, such as 50Hz, 60Hz, 70Hz, 80Hz, 100Hz, 500Hz, 1000Hz, etc.

[0049] In some embodiments, the annealing heat treatment includes: heating to 500℃-950℃ (e.g., 500℃, 600℃, 700℃, 800℃, 900℃, 950℃, etc.) at a heating rate of 5℃ / min-15℃ / min (e.g., 5℃ / min, 10℃ / min, 15℃ / min, etc.) in a hydrogen atmosphere, and holding at that temperature for 10min-4h (10min, 30min, 60min, 2h, 3h, 4h, etc.).

[0050] In some embodiments, before obtaining the soft magnetic alloy, the product of the post-processing is cooled after the post-processing.

[0051] It is understood that the cooling methods described in this application can all include furnace cooling or controlled cooling to room temperature. Controlled cooling includes air cooling, wind cooling, water cooling, etc. It should be noted that the cooling method can be selected according to actual needs.

[0052] A second aspect of this application provides a soft magnetic alloy, which is prepared using the preparation method described in the first aspect. The soft magnetic alloy has a grain size of 5μm-20μm, a yield strength of not less than 800MPa, an elongation of not less than 10%, and a coercivity of not more than 80A / m.

[0053] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0054] Example 1

[0055] A 1J22 alloy billet with a thickness of 0.1 mm is provided, with the following elemental contents: Fe 49.38% by mass, Co 49.2% by mass, V 1.17% by mass, Mn 0.05% by mass, Si 0.037% by mass, C 0.023% by mass, P 0.006% by mass, S 0.001% by mass, Cu 0.006% by mass, and Ni 0.001% by mass. Impurities are unavoidable in the 1J22 alloy billet. The 1J22 alloy billet is cold rolled at room temperature to 0.05 mm, and is designated as intermediate product 1.

[0056] Intermediate product 1 was subjected to pulsed current treatment at room temperature under the following conditions: current density 180 A / mm². 2 The frequency is 100Hz and the total processing time is 5s.

[0057] The material obtained from the electrical pulse treatment was immediately placed in a tube furnace filled with pure hydrogen gas, heated to 800°C at a rate of 10°C / min, held for 30 min, and then cooled with the furnace to obtain a soft magnetic alloy.

[0058] Example 2

[0059] A 1J22 alloy billet with a thickness of 0.1 mm is provided, with the following elemental contents: Fe 49.38% by mass, Co 49.2% by mass, V 1.17% by mass, Mn 0.05% by mass, Si 0.037% by mass, C 0.023% by mass, P 0.006% by mass, S 0.001% by mass, Cu 0.006% by mass, and Ni 0.001% by mass. Impurities are unavoidable in the 1J22 alloy billet. The billet is cold-rolled at room temperature to 0.04 mm, and is designated as intermediate product 2.

[0060] Intermediate product 2 was subjected to annealing heat treatment under the following conditions: in a hydrogen atmosphere, the temperature was increased from room temperature to 860°C at a rate of 10°C / min and held for 20 min.

[0061] After cooling the annealed heat treatment product to room temperature, a pulsed current treatment was applied under the following conditions: current density 120 A / mm². 2 A soft magnetic alloy was obtained by setting a frequency of 500Hz and a duration of 2s.

[0062] Example 3

[0063] A 1J22 alloy billet with a thickness of 0.1 mm is provided, with the following elemental contents: Fe mass fraction 49.38%, Co mass fraction 49.2%, V mass fraction 1.17%, Mn mass fraction 0.05%, Si mass fraction 0.037%, C mass fraction 0.023%, P mass fraction 0.006%, S mass fraction 0.001%, Cu mass fraction 0.006%, and Ni mass fraction 0.001%. Impurities are also unavoidable in the 1J22 alloy billet. The billet is cold rolled at room temperature to 0.03 mm, and is designated as intermediate product 3.

[0064] Intermediate product 3 was subjected to pulsed current treatment at room temperature under the following conditions: current density 200 A / mm². 2 The frequency is 50Hz and the total processing time is 10s.

[0065] Immediately place the product obtained after electrical pulse treatment into a tube furnace filled with pure hydrogen for annealing heat treatment, heating to 750℃ at a rate of 10℃ / min and holding for 15min.

[0066] After cooling the annealed heat treatment product to room temperature, a pulsed current treatment was applied under the following conditions: current density 150 A / mm². 2 A soft magnetic alloy was obtained by setting a frequency of 200Hz and a duration of 3s.

[0067] Comparative Example 1

[0068] A 1J22 alloy billet with a thickness of 0.1 mm was provided, with the following elemental contents: Fe 49.38% by mass, Co 49.2% by mass, V 1.17% by mass, Mn 0.05% by mass, Si 0.037% by mass, C 0.023% by mass, P 0.006% by mass, S 0.001% by mass, Cu 0.006% by mass, and Ni 0.001% by mass. Impurities were unavoidably present in the 1J22 alloy billet. The billet was heat-treated at 900℃ for 2 hours, then cooled to 600℃ and held for 1 hour, and finally air-cooled to obtain a soft magnetic alloy.

[0069] Comparative Example 2

[0070] A 0.1 mm thick 1J22 alloy billet with the following elemental composition is provided: Fe 49.38% by mass, Co 49.2% by mass, V 1.17% by mass, Mn 0.05% by mass, Si 0.037% by mass, C 0.023% by mass, P 0.006% by mass, S 0.001% by mass, Cu 0.006% by mass, and Ni 0.001% by mass. Impurities are unavoidable in the 1J22 alloy billet. The billet is cold-rolled at room temperature to 0.05 mm, and this is designated as intermediate product 4.

[0071] Intermediate product 4 was subjected to electrical pulse treatment only at room temperature, with the following parameters: current density 200 A / mm². 2 The frequency was 50Hz and the total processing time was 10s to obtain a soft magnetic alloy.

[0072] The soft magnetic alloys obtained in Examples 1-3 and Comparative Examples 1-2 were tested as follows, and the results are shown in Table 1:

[0073] Grain size: Determined according to the national standard GB / T 6394-2017 "Method for determination of average grain size of metals".

[0074] Yield strength and elongation: The tests were conducted in accordance with the national standard GB / T 228.1-2021 "Metallic materials - Tensile testing - Part 1: Test method at room temperature".

[0075] Coercivity: The coercivity of soft magnetic materials was measured according to the national standard GB / T 3656-2008 "Measurement Method of Coercivity of Soft Magnetic Materials".

[0076] Table 1 Test results of the examples and comparative examples

[0077]

[0078] As shown in Table 1 above, the soft magnetic alloys prepared in Examples 1-3 achieve excellent synergy of high strength, high elongation, and low coercivity while obtaining fine and uniform grains. In contrast, Comparative Example 1, which only uses traditional heat treatment, although having acceptable strength and elongation, suffers from poor magnetic properties and a coercivity as high as 100 A / m, and has coarse grains (e.g., 35 μm). Comparative Example 2, which only uses single electric pulse treatment, lacks the synergistic effect of annealing heat treatment, resulting in incomplete recrystallization, extremely poor plasticity (elongation <5%), and high coercivity. This fully demonstrates the unique advantage of the synergistic combination of electric pulse and heat treatment sequence in the post-processing of this application in resolving the "strength-plasticity-magnetism" contradiction in alloys like 1J22.

[0079] Figure 2 This is the EBSD grain orientation diagram of the soft magnetic alloy in Example 1. As can be seen from the diagram, the soft magnetic alloy has obtained uniform and fine equiaxed recrystallized grains with random orientation distribution and weak texture. These are the key microstructure features for achieving a synergistic improvement in high strength, good plasticity and low coercivity.

[0080] Figure 3 The figure shows the EBSD grain orientation diagram of the soft magnetic alloy in Comparative Example 1. It can be seen from the figure that the soft magnetic alloy that has undergone only two conventional heat treatments has abnormally large grains and obvious preferred orientations, which is the main reason for the significant increase in its coercivity (102 A / m). This shows that it is difficult to optimize the texture and magnetic properties while refining the grains by relying solely on conventional heat treatment.

[0081] Figure 4 The image shows a TEM image of the soft magnetic alloy in Example 3. It can be seen from the image that a large number of fine nanoscale spherical precipitates are dispersed inside the grains, and typical Laves precipitate particles are present in the soft magnetic alloy. These precipitates can effectively pin grain boundaries and dislocations, refine and stabilize the microstructure, thereby achieving lower coercivity while further improving strength and elongation.

[0082] It should also be noted that the terms "some embodiments," "other embodiments," and "embodiments" used in this application refer to specific features, structures, or characteristics described in connection with those embodiments, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0083] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0084] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of protection of this application. Any equivalent structural or procedural transformations made based on the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of protection of this application.

Claims

1. A method for preparing a soft magnetic alloy, characterized in that, Includes the following steps: A soft magnetic alloy billet is provided, wherein the soft magnetic alloy billet comprises 49%-51% cobalt, 0.8%-1.8% vanadium, no more than 0.04% carbon, no more than 0.3% manganese, no more than 0.3% silicon, no more than 0.02% phosphorus, no more than 0.02% sulfur, no more than 0.02% copper, and no more than 0.05% nickel, with the balance being iron and unavoidable impurities; The soft magnetic alloy blank is subjected to plastic deformation treatment to obtain a plastically deformed part; The plastically deformed part is subjected to post-processing, which includes at least one electrical pulse treatment and at least one annealing heat treatment to obtain the soft magnetic alloy; The conditions for the electrical pulse processing are: current density of 50 A / mm². 2 -300A / mm 2 The time range is 0.1s-60s; the frequency range is 50Hz-1000Hz. The annealing heat treatment includes: heating to 500℃-950℃ in a hydrogen atmosphere at a heating rate of 5℃ / min-15℃ / min, and holding at that temperature for 10min-4h.

2. The preparation method according to claim 1, characterized in that, The plastic deformation treatment includes warm rolling. Before the warm rolling, the soft magnetic alloy billet is held at 600℃-800℃ for 10min-60min. The reduction rate of the warm rolling is 55%-75%.

3. The preparation method according to claim 1, characterized in that, The plastic deformation treatment includes cold rolling, and the cold rolling process includes: The soft magnetic alloy billet is cold-rolled at room temperature, with a reduction rate of 50%-85%.

4. The preparation method according to claim 1, characterized in that, The post-processing is as follows: First, the electrical pulse treatment is performed, and then the product obtained from the electrical pulse treatment is subjected to the annealing heat treatment.

5. The preparation method according to claim 1, characterized in that, The post-processing is as follows: First, the annealing heat treatment is performed, then the product obtained from the annealing heat treatment is cooled to room temperature, and then the cooled intermediate is subjected to the electrical pulse treatment.

6. The preparation method according to claim 1, characterized in that, The post-processing is as follows: First, the first electrical pulse treatment is performed, then the product obtained from the electrical pulse treatment is subjected to the annealing heat treatment, then the product obtained from the annealing heat treatment is cooled to room temperature, and then the cooled intermediate is subjected to the second electrical pulse treatment.

7. The preparation method according to any one of claims 4-6, characterized in that, The post-processing is performed repeatedly, wherein the repeated processing is performed at least twice.

8. A soft magnetic alloy, characterized in that, The soft magnetic alloy is prepared by any one of claims 1-7, and has a grain size of 5μm-20μm, a yield strength of not less than 800MPa, an elongation of not less than 10%, and a coercivity of not more than 80A / m.

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