Soft magnetic alloy with high saturation flux density, high plasticity and corrosion resistance and preparation method thereof

Abstract

The invention discloses a soft magnetic alloy with high saturation flux density, high plasticity and corrosion resistance and a preparation method thereof, belongs to the field of soft magnetic materials, and aims to solve the problem that the magnetic property, the mechanical property and the corrosion resistance of an existing soft magnetic alloy are difficult to cooperate. The alloy is prepared from the following components in percentage by atom: 75.2 to 76.6 at.% of Fe, 10.8 to 11.2 at.% of Co, 10.6 to 10.7 at.% of Cr, 1.2 to 2.8 at.% of Si, 0.4 to 0.6 at.% of Mo and impurities, wherein the total amount of Fe and Co is 86.0 to 87.8 at.%, and the total amount of Cr and Mo is 11.0 to 11.3 at.%; the preparation method comprises the following steps: firstly, carrying out step-by-step vacuum melting to ensure uniform components, and then carrying out suction casting forming, homogenization treatment, cold rolling and annealing to optimize the structure; the obtained alloy has high saturation magnetic induction (Bs is larger than or equal to 1.8 T), low coercive force (Hc is smaller than or equal to 250 A / m), excellent mechanical performance (the tensile strength is larger than or equal to 580 MPa, and the percentage elongation after fracture is larger than or equal to 32%) and outstanding corrosion resistance in a 3.5 wt.% NaCl solution. The material and the process are suitable for severe environments such as ocean engineering and high-speed motors, and have important application value.

Description

Technical Field

[0001] This invention relates to the field of soft magnetic materials technology, and in particular to a soft magnetic alloy with high saturation magnetic induction intensity, high strength and plasticity, and corrosion resistance, and its preparation method. This alloy is suitable for motors and transformers in marine engineering, ship power systems, and other applications that require a balance of soft magnetic properties, mechanical properties, and corrosion resistance. Background Technology

[0002] Soft magnetic materials are core materials in energy conversion devices such as transformers and motors, and their performance directly determines the efficiency, power density, and reliability of the equipment. Ideal soft magnetic materials must simultaneously possess high saturation magnetic induction. (To achieve high-efficiency conversion and device miniaturization), low coercivity (To reduce hysteresis loss) and good mechanical and corrosion resistance properties. In harsh environments such as marine engineering and ship power systems, materials also need to withstand high salt spray corrosion and huge centrifugal forces from high-speed rotation. Therefore, developing soft magnetic alloys with high magnetic induction, low loss, high strength and plasticity and excellent corrosion resistance has become a key technical challenge.

[0003] Existing soft magnetic alloys are mainly divided into two categories. One category is traditional crystalline alloys, such as Fe-Si, Fe-Ni, and Fe-Co systems, which have excellent soft magnetic properties but generally suffer from insufficient strength, limited plasticity, and poor corrosion resistance (especially in chloride ion environments). Although adding Cr can significantly improve corrosion resistance, its antiferromagnetism severely deteriorates magnetic properties, leading to a significant decrease in the permeability of existing corrosion-resistant soft magnetic alloys (such as the high-Cr Fe-Cr-Mo system). The other category is novel amorphous / nanocrystalline soft magnetic alloys (such as Fe-Si-B and Fe-Cu-Nb-Si-B systems), which have excellent magnetic properties and relatively good corrosion resistance, but are intrinsically brittle, difficult to process and form, and cannot meet the requirements of plasticity and machinability for complex components.

[0004] The core challenge facing current technology lies in the mutual constraints between soft magnetic properties, mechanical properties, and corrosion resistance. Traditional methods of strengthening alloys through solid solution, grain boundary strengthening, and precipitation introduce internal stress, hindering the movement of magnetic domain walls and leading to increased coercivity and magnetic loss. Conversely, improving corrosion resistance often requires adding elements that impair magnetism (such as high Cr content) or forming non-magnetic phases. Therefore, existing technologies struggle to synergistically achieve "high" magnetic properties within the same material system. ,Low The comprehensive goal of "high strength, high plasticity, and corrosion resistance" urgently requires breakthroughs in this bottleneck through new alloy design and preparation processes. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a soft magnetic alloy with high saturation magnetic induction, high strength and plasticity, and corrosion resistance, and its preparation method, aiming to solve the technical difficulty of traditional soft magnetic alloys simultaneously possessing high saturation magnetic induction, excellent mechanical properties, and outstanding corrosion resistance. By designing a specific Fe-Co-Cr-Mo-Si composition system and optimizing its atomic percentage, combined with stepwise vacuum melting, homogenization treatment, cold rolling, and annealing processes, microstructure control and composition homogenization are achieved, ultimately preparing a soft magnetic alloy with high magnetic induction (…). We aim to develop soft magnetic alloys with low coercivity, high strength and plasticity, and excellent resistance to corrosion in marine environments to meet the urgent needs of marine engineering, special motors and other fields for high-performance soft magnetic materials.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A soft magnetic alloy with high saturation magnetic induction intensity, high strength and plasticity, and corrosion resistance, wherein the alloy composition by atomic percentage is: Fe 75.2-76.6 at.%, Co 10.8-11.2 at.%, Cr 10.6-10.7 at.%, Si 1.2-2.8 at.%, Mo 0.4-0.6 at.%, with the balance being unavoidable impurities.

[0008] A further improvement of the technical solution of the present invention is that the total atomic percentage of Fe and Co in the alloy is 86.0 to 87.8 at.%, and the total atomic percentage of Cr and Mo is 11.0 to 11.3 at.%.

[0009] A method for preparing a soft magnetic alloy with high saturation magnetic induction intensity, high strength and ductility, and corrosion resistance includes the following steps:

[0010] Step 1, Raw material pretreatment: Weigh the purity... The elemental raw materials are surface-polished, cleaned, and dried.

[0011] Step 2, Step-by-step vacuum melting: Group the raw materials according to their melting points, and melt them under vacuum. Under these conditions, first melt the high melting point group, then add the medium melting point group and combine them, and repeat the melting process at least 5 times to obtain an alloy ingot with uniform composition.

[0012] Step 3, suction casting: The alloy ingot is remelted and poured into a water-cooled copper mold, and cooled to obtain an alloy ingot;

[0013] Step 4, Homogenization treatment: The alloy ingot is held at 1100-1200℃ for 1-10 hours, followed by water quenching;

[0014] Step 5, Cold rolling: The homogenized alloy ingot is cold rolled with a total reduction rate of 70-90%.

[0015] Step 6, Annealing optimization: The cold-rolled alloy is held at 700-800℃ for 8-12 hours under argon protection, and then cooled in the furnace at a rate of 5-10℃ / min.

[0016] A further improvement of the technical solution of the present invention is that: in step 1, the drying temperature is 120°C and the time is 2 hours.

[0017] A further improvement of the technical solution of the present invention is that: in step 2, the high melting point group is Cr and Mo, and the medium melting point group is Fe, Co and Si; during smelting, the smelting current of the high melting point group is 350-500A, the smelting current of the medium melting point group is 200-350A, and the ingot is flipped after each smelting.

[0018] A further improvement of the technical solution of the present invention is that: in step 3, the temperature of the alloy melt during casting is 1550-1600℃.

[0019] A further improvement of the technical solution of the present invention is that: in step 4, the homogenization process is carried out under vacuum conditions.

[0020] A further improvement of the technical solution of the present invention is that, in step 5, the thickness of the alloy sheet obtained after cold rolling is 0.65 to 2 mm.

[0021] A further improvement of the technical solution of the present invention lies in: the saturation magnetic induction intensity of the alloy. coercivity ,

[0022] A further improvement of the technical solution of the present invention lies in: the tensile strength of the alloy. It also exhibits excellent corrosion resistance in 3.5 wt.% NaCl solution.

[0023] The technological advancements achieved by this invention due to the adoption of the above technical solutions are as follows:

[0024] 1. This invention achieves an optimal ratio of magnetic main elements (Fe, Co), corrosion-resistant functional elements (Cr, Mo), and microstructure regulating elements (Si) through precise alloy composition design. By combining stepwise melting, homogenization, and cold rolling-annealing processes, it achieves microstructural refinement and compositional homogenization at the micro level, and successfully integrates high saturation magnetic induction intensity, low coercivity, high strength and ductility, and excellent resistance to marine environmental corrosion at the macro level, breaking through the bottleneck of mutual constraints among these properties in traditional alloys.

[0025] 2. The alloy prepared by this invention ensures high saturation magnetic induction intensity ( While maintaining low coercivity, it also achieved a high level of coercivity. This indicates that the material possesses both high magnetic energy conversion potential and low hysteresis loss characteristics, meeting the key requirements of high-efficiency, energy-saving, and miniaturized magnetic devices for core soft magnetic materials.

[0026] 3. This invention achieves a stable and dense passivation film on the alloy surface by controlling the content of Cr and Mo elements. In a 3.5 wt.% NaCl solution simulating a marine environment, the corrosion rate of the alloy is no higher than 0.03 mm / a, demonstrating excellent resistance to chloride ion corrosion, making it suitable for direct application in harsh corrosive environments such as ship power systems and offshore platforms.

[0027] 4. The alloy prepared by this invention has a tensile strength of not less than 580 MPa and an elongation after fracture of not less than 32%, demonstrating a combination of high strength and good plasticity. This feature ensures that the material can withstand huge centrifugal forces when used as components such as high-speed motor rotors. At the same time, its good plasticity also facilitates subsequent cutting, stamping and other processing and forming, overcoming the shortcomings of traditional amorphous / nanocrystalline soft magnetic alloys, such as high brittleness and difficulty in processing.

[0028] 5. The preparation process adopted in this invention is clear and the parameters are well controlled. Through vacuum melting, homogenization treatment and controllable cold rolling-annealing process, alloy plates with uniform properties can be stably prepared, which has good process reproducibility and potential for large-scale production. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a metallographic diagram of the alloy prepared in Example 1 of the present invention;

[0031] Figure 2 This is a statistical analysis chart of the grain size of the alloy prepared in Example 1 of the present invention;

[0032] Figure 3 This is a hysteresis loop diagram of the alloy prepared in Example 1 of the present invention;

[0033] Figure 4 This is a potentiodynamic polarization curve of samples with different components in a 3.5 wt.% NaCl solution in an embodiment of the present invention;

[0034] Figure 5 This is a room temperature tensile stress-strain curve of the alloy of the present invention under different Si atomic percentages in the embodiments of the present invention. Detailed Implementation

[0035] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device 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 or devices.

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0037] A soft magnetic alloy with high saturation magnetic induction, high strength and ductility, and corrosion resistance, and its alloy composition design and principle:

[0038] This invention uses Fe and Co as the main ferromagnetic components (providing high magnetic moments and ensuring saturation magnetic induction); Cr and Mo as corrosion-resistant functional components (forming a dense passivation film and improving corrosion resistance); and Si as an element for microstructure regulation and performance optimization (refining grains, optimizing alloy microstructure, and assisting in balancing magnetic properties and corrosion resistance). Each element is optimized and controlled according to its atomic percentage to achieve simultaneous improvement in magnetic properties, mechanical properties, and corrosion resistance.

[0039] Specific composition (atomic percentage, at.%): Fe 75.2~76.6at.%, Co 10.8~11.2at.%, Cr 10.6~10.7at.%, Mo 0.4~0.6at.%, Si 1.2~2.8at.%, with the balance being unavoidable impurities.

[0040] Preferably, the total atomic percentage of Fe and Co is 86.0–87.8 at.% (to ensure the magnetic moment and achieve saturation magnetic induction). The total atomic percentage of Cr and Mo is 11.0 to 11.3 at.% (forming a stable passivation film and improving corrosion resistance in corrosive media).

[0041] A preparation method and process principle of a soft magnetic alloy with high saturation magnetic induction intensity, high strength and plasticity, and corrosion resistance:

[0042] This invention employs a "stepwise vacuum melting-suction casting-homogenization-cold rolling-annealing" process. Stepwise melting ensures uniform mixing of high / medium melting point elements, homogenization and cold rolling refine grains and eliminate segregation, and annealing optimizes the magnetic domain structure, ultimately achieving a synergistic improvement in magnetic properties, mechanical properties and corrosion resistance.

[0043] Specific steps:

[0044] Step 1, Raw material pretreatment: Weigh the purity... The Fe, Co, Cr, Si, and Mo elemental raw material particles are sanded (to remove the oxide layer), ultrasonically cleaned (15-20 min to remove oil stains), and then dried at 120℃ for 2 h for later use.

[0045] Step 2, Step-by-step vacuum melting: Place Cr and Mo (high melting point group) and Fe, Co, and Si (medium melting point group) separately into different copper crucibles in a vacuum arc melting furnace; evacuate the furnace until... Argon gas protection is applied afterward; first, the high melting point group is melted with a current of 350-500A (and held at that temperature for 2-5 minutes after melting), and then the medium melting point group is melted with a current of 200-350A. Then, the two groups of gold ingots are combined and melted repeatedly ≥5 times (the alloy ingots are turned over after each melting to ensure uniform composition).

[0046] Step 3, suction casting: The combined alloy ingots are suction cast into a water-cooled copper mold at 1550–1600°C, and then cooled to room temperature. Alloy ingots of a specific size.

[0047] Step 4, Homogenization treatment: The alloy ingot is placed in a tube furnace and heated to 1100-1200℃ under vacuum conditions by a mechanical pump. After holding at this temperature for 1-10 hours, it is cooled by water quenching (rapid cooling eliminates component segregation and refines grains).

[0048] Step 5, cold rolling: The homogenized ingot is cold rolled, and the total reduction is controlled at 70-90% to obtain an alloy sheet with a thickness of 0.65-2mm (cold rolling introduces deformation energy storage, which provides conditions for subsequent annealing optimization).

[0049] Step 6, Annealing optimization: The cold-rolled sheet is placed in a small muffle furnace and heated to 700-800℃ under argon atmosphere protection. After holding at this temperature for 8-12 hours, it is cooled with the furnace at a rate of 5-10℃ / min (annealing releases deformation energy, optimizes magnetic domain structure, and reduces coercivity).

[0050] The present invention will be further described below with reference to the embodiments (all components in the embodiments are atomic percentages, at.%). The description of the technical features described below is based on representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments.

[0051] Example 1

[0052] A soft magnetic alloy with high saturation magnetic induction, high strength and ductility, and corrosion resistance:

[0053] 1) Composition design: Fe 76.6%, Co 11.0%, Cr 10.7%, Si 1.2%, Mo 0.5%.

[0054] 2) Preparation process:

[0055] Step 1, Material pretreatment: Weigh each elemental raw material according to the ratio, polish with sandpaper, ultrasonically clean, and dry at 120℃ for 2 hours;

[0056] Step 2, Vacuum melting in stages: The high melting point group (Cr, Mo) is melted with a current of 450A and held at that temperature for 3 minutes; the medium melting point group (Fe, Co, Si) is melted with a current of 300A. The two groups are then melted together and the melting process is repeated 6 times (the ingot is turned over each time).

[0057] Step 3, suction casting: Under argon atmosphere, the alloy is injected into a water-cooled copper mold at 1580℃ and cooled to obtain an alloy ingot;

[0058] Step 4, Homogenization treatment: Hold at 1150℃ for 2 hours, then water quench;

[0059] Step 5, cold rolling: total reduction rate of 80%, to obtain a sheet with a thickness of 1.3mm;

[0060] Step 6, Annealing optimization: Hold at 750℃ for 10 hours, then cool with the furnace at a rate of 8℃ / min.

[0061] 3) Performance testing:

[0062] Magnetic properties: , ;

[0063] Corrosion resistance: Corrosion rate in 3.5 wt.% NaCl solution = 0.015 mm / a, such as... Figure 4 As shown;

[0064] Mechanical properties: Tensile strength = 585 MPa, elongation after fracture = 32%, such as Figure 5 As shown.

[0065] Cut from the center of the annealed alloy sheet The samples were polished sequentially with sandpaper ranging from 400# to 2000#, then polished with diamond polishing paste (1μm particle size) until the surface was free of scratches. Subsequently, they were etched with aqua regia (a mixture of concentrated hydrochloric acid and concentrated nitric acid in a volume ratio of 3:1) for 15 seconds, rinsed with water, and dried. The microstructure was then observed under an optical microscope.

[0066] like Figure 1 As shown, the alloy exhibits a uniform equiaxed crystal structure with no obvious elemental segregation or second-phase precipitation, and the grain boundaries are clear and complete; Figure 2 The grain size histogram shown indicates that the grain size distribution ranges from 8.2 to 22.5 μm. Statistical calculations using Image-Pro Plus software revealed the average grain size... The fine and uniform grain structure benefits from the compositional homogenization effect of stepwise vacuum melting and the grain recrystallization control during annealing, laying the foundation for the alloy to simultaneously achieve high magnetic properties and corrosion resistance.

[0067] In magnetic property testing, by Figure 3 As can be seen, the curve exhibits the narrow hysteresis loop characteristic of typical soft magnetic materials. The loop is symmetrical on both sides and rapidly approaches saturation, intuitively reflecting the alloy's easy magnetization and demagnetization characteristics. Quantitative analysis of the curve reveals that the alloy's saturation magnetic induction intensity... Reaching 1.91T, coercivity The value is 210 A / m, which meets the trade-off between high saturation magnetic induction and low coercivity.

[0068] For Example 1 (corresponding) Figure 5 The black curve (Si atomic percentage 1.2%) and the room temperature stress-strain curves of alloy samples with different Si contents in the same system.

[0069] Depend on Figure 5 As can be seen from the curves, the alloy of the present invention exhibits excellent strength-ductility matching characteristics. Taking the black curve corresponding to Example 1 as an example, its tensile strength reaches about 580 MPa and its elongation exceeds 30%. When the Si content is increased to 2.0% (green curve), the tensile strength further increases to about 642 MPa, and the elongation remains above 35%. Even when the Si content is increased to 2.4% (blue curve), the tensile strength is still maintained at about 647 MPa and the elongation is 32%.

[0070] This result confirms the flexibility of the composition design in this invention: by adjusting the percentage of Si atoms (1.2%–2.4%), soft magnetic properties can be guaranteed. , It achieves a balance between excellent corrosion resistance and mechanical properties (tensile strength 580–640 MPa, elongation 30%–36%). This is in contrast to existing technologies using traditional soft magnetic materials (such as non-oriented silicon steel, where tensile strength is often below 550 MPa and elongation is low). The alloy prepared by this invention not only overcomes the limitation of "insufficient mechanical properties of soft magnetic materials" but also avoids the brittle defects of amorphous materials, achieving a synergistic improvement in performance of "high magnetic induction, strong corrosion resistance, and excellent mechanical properties", providing more dimensions of adaptability for the selection of materials for electromagnetic devices under different working conditions.

[0071] Example 2

[0072] A soft magnetic alloy with high saturation magnetic induction, high strength and ductility, and corrosion resistance:

[0073] 1) Composition design: Fe 75.8%, Co 11.0%, Cr 10.7%, Si 2.0%, Mo 0.5%.

[0074] 2) Preparation process:

[0075] Step 1, Raw material pretreatment: Same as in Example 1;

[0076] Step 2, step-by-step vacuum melting: the high melting point group is melted with a current of 500A and held at that temperature for 4 minutes; the medium melting point group is melted with a current of 250A, and the two groups are combined and melted repeatedly 5 times.

[0077] Step 3, suction casting: The alloy ingot is suction cast into a water-cooled copper mold at 1600℃ and cooled to obtain an alloy ingot;

[0078] Step 4, Homogenization treatment: Hold at 1200℃ for 5 hours, then water quench;

[0079] Step 5, cold rolling: total reduction rate of 90%, to obtain a sheet with a thickness of 0.65mm;

[0080] Step 6, Annealing optimization: Hold at 800℃ for 8 hours, then cool with the furnace at a rate of 10℃ / min.

[0081] 3) Performance testing:

[0082] Magnetic properties: , ;

[0083] Corrosion resistance: Corrosion rate in 3.5 wt.% NaCl solution = 0.007 mm / a, such as... Figure 4 As shown;

[0084] Mechanical properties: Tensile strength = 642 MPa, elongation after fracture = 36%, such as Figure 5 As shown;

[0085] Cut from alloy sheet The sample was encapsulated in epoxy resin and exposed. The test surface, after grinding and polishing, was subjected to potentiodynamic polarization testing in a 3.5 wt.% NaCl solution (using an electrochemical workstation): a saturated calomel electrode was used as the reference electrode, a platinum sheet as the counter electrode, and the sample as the working electrode. Before testing, the sample was immersed in the solution for 2 hours to achieve a stable state. The scan rate was 1 mV / s, and the scan range was [missing information]. (Relative to open circuit potential).

[0086] Corresponding to the red curve marked Example 2 in Figure 4, the corrosion potential of this alloy The corrosion current density was calculated using the Tafel extrapolation method. It is significantly lower than that of other component samples (such as...) Sample This indicates that it has excellent corrosion resistance in simulated marine corrosive media, which is closely related to the dense passivation film formed by Cr and Mo elements and the uniform grain structure.

[0087] Example 3

[0088] A soft magnetic alloy with high saturation magnetic induction, high strength and ductility, and corrosion resistance:

[0089] 1) Composition design: Fe 75.4%, Co 1.0%, Cr 10.7%, Si 2.4%, Mo 0.5%.

[0090] 2) Preparation process:

[0091] Step 1, Raw material pretreatment: Same as in Example 1;

[0092] Step 2, step-by-step vacuum melting: the high melting point group is melted with a current of 450A and held at that temperature for 5 minutes; the medium melting point group is melted with a current of 350A, and the two groups are combined and melted repeatedly 7 times.

[0093] Step 3, suction casting: The alloy ingot is suction cast into a water-cooled copper mold at 1550℃ and cooled to obtain an alloy ingot;

[0094] Step 4, Homogenization treatment: Hold at 1100℃ for 8 hours, then water quench;

[0095] Step 5, cold rolling: total reduction rate of 70%, to obtain a sheet with a thickness of 1.95mm;

[0096] Step 6, Annealing optimization: Hold at 700℃ for 12 hours, then cool with the furnace at a rate of 5℃ / min.

[0097] 3) Performance testing:

[0098] Magnetic properties: , ;

[0099] Corrosion resistance: Corrosion rate in 3.5 wt.% NaCl solution = 0.027 mm / a, such as... Figure 4 As shown;

[0100] Mechanical properties: Tensile strength = 647 MPa, elongation after fracture = 32%, such as Figure 5 As shown.

[0101] Furthermore, the upper and lower limits and ranges of the process parameters of this invention (such as atomic percentage, time, temperature, current, total reduction, thickness, rate, etc.) can all achieve this invention, and examples are not listed here.

[0102] In summary, the soft magnetic alloy and its preparation method provided by this invention have successfully developed a new type of soft magnetic material that simultaneously meets the requirements of high efficiency, high reliability, long life and resistance to harsh environments. It is particularly suitable for marine engineering equipment, special motors and transformers, and other fields that have comprehensive requirements for soft magnetic properties, mechanical load-bearing capacity and corrosion resistance, and has important engineering application value.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A soft magnetic alloy with high saturation magnetic induction intensity, high strength and plasticity, and corrosion resistance, characterized in that, The alloy has the following composition by atomic percentage: Fe 75.2-76.6 at.%, Co 10.8-11.2 at.%, Cr 10.6-10.7 at.%, Si 1.2-2.8 at.%, Mo 0.4-0.6 at.%, with the balance being unavoidable impurities.

2. The high saturation magnetic induction intensity, high strength and plasticity, corrosion-resistant soft magnetic alloy according to claim 1, characterized in that, The total atomic percentage of Fe and Co in the alloy is 86.0–87.8 at.%, and the total atomic percentage of Cr and Mo is 11.0–11.3 at.%.

3. A method for preparing a soft magnetic alloy with high saturation magnetic induction intensity, high strength and plasticity, and corrosion resistance as described in claim 1 or 2, characterized in that, Includes the following steps: Step 1, Raw material pretreatment: Weigh the elemental raw materials with a purity ≥ 99.95% wt.%, and then perform surface polishing, cleaning and drying; Step 2, Step-by-step vacuum melting: Group the raw materials according to their melting points, and melt them under vacuum. Under these conditions, first melt the high melting point group, then add the medium melting point group and combine them, and repeat the melting process at least 5 times to obtain an alloy ingot with uniform composition. Step 3, suction casting: The alloy ingot is remelted and poured into a water-cooled copper mold, and cooled to obtain an alloy ingot; Step 4, Homogenization treatment: The alloy ingot is held at 1100-1200℃ for 1-10 hours, followed by water quenching; Step 5, Cold rolling: The homogenized alloy ingot is cold rolled with a total reduction rate of 70-90%. Step 6, Annealing optimization: The cold-rolled alloy is held at 700-800℃ for 8-12 hours under argon protection, and then cooled in the furnace at a rate of 5-10℃ / min.

4. The preparation method according to claim 3, characterized in that, In step 1, the drying temperature is 120°C and the drying time is 2 hours.

5. The preparation method according to claim 3, characterized in that, In step 2, the high melting point group consists of Cr and Mo, and the medium melting point group consists of Fe, Co and Si. During smelting, the smelting current for the high melting point group is 350-500A, and the smelting current for the medium melting point group is 200-350A. The ingot is flipped after each smelting.

6. The preparation method according to claim 3, characterized in that, In step 3, the temperature of the alloy melt during casting is 1550–1600℃.

7. The preparation method according to claim 3, characterized in that, In step 4, the homogenization process is performed under vacuum conditions.

8. The preparation method according to claim 3, characterized in that, In step 5, the thickness of the alloy sheet obtained after cold rolling is 0.65 to 2 mm.

9. The high saturation magnetic induction intensity, high strength and plasticity, corrosion-resistant soft magnetic alloy according to claim 1 or 2, characterized in that, The saturation magnetic induction intensity of the alloy coercivity .

10. The high saturation magnetic induction intensity, high strength and plasticity, corrosion-resistant soft magnetic alloy according to claim 1 or 2, characterized in that, The tensile strength of the alloy It also exhibits excellent corrosion resistance in 3.5 wt.% NaCl solution.

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