Fe-si-b iron-based amorphous alloy ribbon with high saturation magnetic induction and preparation method and application thereof

Abstract

This invention belongs to the field of metallic materials technology, specifically relating to a Fe-Si-B iron-based amorphous alloy thin strip with high saturation magnetic induction intensity, its preparation method, and its applications. The mass percentage expression of the alloy is Fe... (100‑x‑y) Si x B y Where x is 0.2–3.5 and y is 2–4.5, and 4.2 ≤ x + y ≤ 5.5. This invention optimizes the soft magnetic properties of Fe-Si-B amorphous alloys by adjusting the addition ratio (x:y) of the metalloid elements Si and B, reducing their coercivity, and obtaining Fe-based amorphous alloys with excellent soft magnetization properties. The preparation method is simple and easy to implement, does not contain expensive metals, and has low development costs. The magnetization of this amorphous alloy increases sharply with the increase of the magnetic field under low magnetic field conditions and then gradually reaches saturation, exhibiting typical soft magnetic properties. It is particularly suitable for manufacturing cores of soft magnetic devices such as high-efficiency distribution transformers, drive motors for new energy vehicles, and high-frequency inductors.

Description

Technical Field

[0001] This invention belongs to the field of metallic materials technology, specifically relating to a Fe-Si-B iron-based amorphous alloy thin strip with high saturation magnetic induction intensity, its preparation method, and its application. Background Technology

[0002] Amorphous alloys possess excellent properties such as corrosion resistance, high strength, and high elasticity due to their short-range ordered and long-range disordered atomic arrangement. While traditional grain-oriented silicon steel offers the advantage of high saturation magnetic induction, its high high-frequency losses make it difficult to meet the energy-saving and miniaturization requirements of modern power electronic equipment. Iron-based amorphous alloys, with their high permeability, high resistivity, high saturation magnetic induction, and low coercivity, are widely used in distribution transformers.

[0003] However, the saturation magnetic induction of the most widely used Fe-Si-B amorphous alloys (such as Fe78Si9B13 and Fe82Si4B13C1) is typically between 1.56T and 1.64T, far lower than that of silicon steel. This performance limitation results in amorphous transformers being larger in size, significantly restricting their widespread application in the field of distribution transformers.

[0004] The most direct way to increase Bs is to increase the Fe content in the alloy. However, in the Fe-Si-B ternary system, as the Fe content increases (especially when the Fe mass fraction exceeds 93%), the amorphous forming ability (GFA) of the alloy decreases sharply. This causes the α-Fe crystalline phase to precipitate easily during rapid cooling of the melt, resulting in a significant increase in the material's coercivity (Hc > 100 A / m) and brittleness, making it impossible to wind and form. In existing technologies, the amorphous forming ability of high-Fe alloys is usually improved by adding elements such as Y, Ni, Nb, and Zr. However, rare earth elements are expensive, and refractory elements such as Nb and Zr increase the difficulty and cost of smelting. Therefore, developing a technology that does not contain expensive metals, relies solely on the Fe-Si-B ternary composition for control, and can produce fully amorphous, high-Bs strips under conventional industrial production conditions is a pressing problem for the industry. Summary of the Invention

[0005] To address the problems in existing technologies, this invention provides a Fe-Si-B iron-based amorphous alloy thin strip with high saturation magnetic induction, its preparation method, and its applications. This alloy, without relying on the addition of expensive rare earth elements or refractory metals, can achieve the production of a thin strip material with a fully amorphous structure, high Bs, and low Hc under conventional industrial production conditions simply by precisely controlling the content and ratio of Si and B, two metalloid elements, in the Fe-Si-B ternary system.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a Fe-Si-B iron-based amorphous alloy thin strip with high saturation magnetic induction intensity. The mass percentage composition expression of the amorphous alloy thin strip is Fe(100-xy)SixBy, wherein the value of x ranges from 0.2 to 3.5, the value of y ranges from 2 to 4.5, and satisfies: 4.2 ≤ x+y ≤ 5.5, preferably 4.5.

[0007] As a further preferred embodiment of the technical solution of the present invention, the thickness of the amorphous alloy strip is 16-24 μm. This thickness range is the preferred result for achieving good amorphous state formation and soft magnetic property balance, and the optimal thickness is 22 μm.

[0008] This invention targets the common Fe-Si-B system of iron-based alloys. By adjusting the addition ratio (x:y) of the metalloid elements Si and B, the soft magnetic properties of Fe-Si-B amorphous alloys are optimized, thereby increasing their saturation magnetic induction and reducing their coercivity, resulting in Fe-based amorphous alloys with excellent soft magnetization properties.

[0009] This invention controls the appropriate content of the addition ratio (x:y) of the metallic elements Si and B in amorphous materials. An inappropriate ratio will lead to the deterioration of soft magnetic properties.

[0010] In a preferred embodiment of the Fe-Si-B amorphous alloy of the present invention, the amorphous alloy strip is composed of any of the following components: a) Fe95.5Si2B2.5, where the mass ratio of Si to B is 1:1.25. This expression indicates that the amorphous alloy has lower coercivity, higher magnetization, and better overall soft magnetic properties. b) Fe95.5Si1.5B3, wherein the mass ratio of Si to B is 1:2; c) Fe95.5Si1B3.5, wherein the mass ratio of Si to B is 1:3.5.

[0011] Secondly, the present invention provides a method for preparing the above-mentioned Fe-Si-B iron-based amorphous alloy thin strip, comprising the following steps: S1. Alloy melting and ingot preparation: Weigh Fe, Si, and B elemental raw materials with a purity of not less than 99.9% according to the designed composition, and place them in a crucible in the order of the lowest melting point at the bottom and the highest melting point at the top; after evacuating to below 3.5×10-3 Pa, fill the furnace with protective gas to a pressure of -0.06 MPa, melt all the raw materials, and obtain an alloy ingot after cooling; after turning the alloy ingot over, repeat the melting at least once under magnetic stirring to obtain an alloy ingot with uniform composition; S2. Single-roll melt quenching and forming: The alloy ingot obtained in step S1 is placed in a single-roll melt quenching device. Protective gas is introduced into the device under vacuum to a pressure of 400 mbar. After the alloy is melted, the molten alloy liquid drips onto the surface of the rotating cooling roller and quickly solidifies to form an amorphous alloy strip. S3. Annealing treatment: The amorphous alloy strip obtained in step S2 is annealed in a protective atmosphere at 300-400°C for 15 minutes.

[0012] In a preferred embodiment of the preparation method described in this invention, in step S1, the protective gas is high-purity argon with a purity of not less than 99.95 wt%.

[0013] As a preferred embodiment of the preparation method described in this invention, the Fe, Si, and B elemental raw materials are ultrasonically cleaned sequentially with petroleum ether and anhydrous ethanol before use.

[0014] In a preferred embodiment of the preparation method described in this invention, the melting under magnetic stirring is performed 6 times in step S1.

[0015] Thirdly, the present invention provides the application of the above-mentioned Fe-Si-B iron-based amorphous alloy thin strip in the preparation of soft magnetic materials.

[0016] As a preferred embodiment of the application described in this invention, the soft magnetic material is used to manufacture high-efficiency power distribution transformer cores, new energy vehicle drive motor cores, or high-frequency inductor cores.

[0017] As a preferred embodiment of the application described in this invention, the soft magnetic material is used to fabricate a magnetic sensor element.

[0018] Advantages and beneficial effects of the present invention: This invention achieves a significant cost reduction by replacing some of the expensive boron with inexpensive silicon (Si), within an extremely narrow window of only 5.5% metalloid addition. Compared to similar high-Bs alloys, raw material costs can be reduced by 10%-15%. Simultaneously, with the strong support of high iron content, the alloy's saturation magnetic induction intensity remains stable between 1.68T and 1.74T, reaching or even exceeding the level of some nanocrystalline alloys. After stress-relief annealing, the coercivity decreases to 1.2-4 A / m, exhibiting excellent soft magnetic properties and broad application prospects in the field of magnetic materials. Attached Figure Description

[0019] Figure 1 The X-ray diffraction patterns of the Fe-Si-B amorphous alloys in Examples 1-6 of this invention are shown below. Figure 2 X-ray diffraction patterns of the Fe-Si-B amorphous alloys of Comparative Examples 1-3 of this invention; Figure 3The saturation magnetization curves of the Fe-Si-B amorphous alloys in Examples 1-6 of this invention are shown. Figure 4 The graphs show the saturation magnetization of the Fe-Si-B amorphous alloys in Comparative Examples 1-3 of this invention. Detailed Implementation

[0020] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to the accompanying drawings and specific embodiments. Unless otherwise specified, other materials and reagents used in the following embodiments are commercially available.

[0021] Example 1

[0022] This embodiment provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 95.5 Si2B 2.5 The metalloid elements Si and B are added in a ratio of 1:1.25, and the preparation method includes the following steps: S1. Using Fe, Si, and B elements with a purity of not less than 99.9% as raw materials, the elements are weighed according to the mass percentage of the alloy composition, and then placed in a copper crucible in the order of lowest melting point to highest melting point. The crucible is then evacuated to a vacuum of 3.5 × 10⁻⁶. -3 Pa, then introduce high-purity argon gas with a purity of 99.99wt% as a protective gas until the pressure inside the furnace reaches -0.06Mpa and stop the gas supply; melt all the raw materials, and after all the raw materials have melted to form an alloy ingot, cool and flip the alloy ingot, melt it again and turn on the magnetic stirring, with a melting current of 450A, repeat the melting 6 times to obtain the alloy ingot. S2. Place the alloy ingot from step S1 into the quartz tube of the single-roller melt quenching system, evacuate the vacuum, and introduce argon gas to 400 mbar. After the alloy ingot is completely melted, drip it onto the rotating copper roller, cool and form it to obtain a Fe-Si-B amorphous alloy strip with a thickness of 18 μm.

[0023] S3. Anneal the alloy strip obtained in step S2 in a medium-frequency induction furnace at 300°C for 15 minutes under a protective atmosphere.

[0024] Example 2

[0025] This embodiment provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 95.5 Si 1.5 B3, with a metalloid element Si and B added in a ratio of 1:2, is prepared in a manner similar to that of Example 1, except that the annealing temperature in step S3 is 330°C.

[0026] Example 3

[0027] This embodiment provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 95.5 Si1B 3.5 The ratio of metalloid elements Si and B added is 1:3.5. The preparation method is basically the same as in Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 22 μm and the annealing temperature in step S3 is 360℃.

[0028] Example 4

[0029] This embodiment provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 95 Si 0.5 B 4.5 The ratio of metalloid elements Si and B added is 1:9. The preparation method is basically the same as in Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 24 μm and the annealing temperature in step S3 is 400℃.

[0030] Example 5

[0031] This comparative example provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 95.8 Si 0.2 B4, with a metalloid element Si and B added in a ratio of 1:20, is prepared in a manner similar to that of Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 20 μm and the annealing temperature in step S3 is 400 °C.

[0032] Example 6

[0033] This comparative example provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 94.5 Si 3.5 B2, with a metalloid element Si and B added in a ratio of 1.5:1, is prepared in a manner similar to that of Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 18 μm and the annealing temperature in step S3 is 300 °C.

[0034] Comparative Example 1 This comparative example provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 94 Si4B2, with a metalloid element Si and B added in a ratio of 2:1, is prepared in a manner similar to that of Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 22 μm and the annealing temperature in step S3 is 330 °C.

[0035] Comparative Example 2 This comparative example provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 94Si2B4, with a metalloid element Si and B added in a ratio of 1:2, is prepared in a manner similar to that of Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 20 μm and the annealing temperature in step S3 is 310 °C.

[0036] Comparative Example 3 This comparative example provides an Fe-Si-B amorphous alloy, whose mass percentage is expressed as Fe 94 Si3B3, with a metalloid element Si and B added in a 1:1 ratio, is prepared in a manner similar to that of Example 1, except that the thickness of the amorphous alloy strip obtained in step S2 is 24 μm and the annealing temperature in step S3 is 300 °C.

[0037] Next, the Fe-Si-B amorphous alloy strips of Examples 1-6 and Comparative Examples 1-3 were tested: I. X-ray diffraction patterns of Fe-Si-B amorphous alloy thin strips from Examples 1-6 and Comparative Examples 1-3 were measured.

[0038] Using an X-ray diffractometer (XRD), Kα rays (λ=0.15406 nm) generated by a copper target were used for scanning. The scanning range was 30°~90° and the scanning speed was 4° / min to obtain the 2θ-intensity spectrum.

[0039] The X-ray diffraction patterns of Fe-Si-B amorphous alloy thin strips in Examples 1-6 are as follows: Figure 1 As shown, the results indicate that the diffraction peaks of the Fe-Si-B amorphous alloy thin strip in the embodiment do not have obvious sharp crystallization peaks, but are typical amorphous structure “bun peak” characteristics, indicating that it is a completely amorphous structure.

[0040] The X-ray diffraction patterns of the Fe-Si-B amorphous alloy thin strips in Examples 1-3 are as follows: Figure 2 As shown, the results indicate that the diffraction peaks of the Fe-Si-B amorphous alloy thin strip in the embodiment do not have obvious sharp crystallization peaks, but are typical amorphous structure “bun peak” characteristics, indicating that it is a completely amorphous structure.

[0041] 2. The coercivity and saturation magnetization of the amorphous alloys of Examples 1-6 and Comparative Examples 1-3 were tested.

[0042] The vibration sample magnetometer (VSM) is used to test the sample in the coil. An alternating signal is induced in the detection coil by the vibration of the sample in the coil. The alternating voltage is proportional to the magnetic moment of the sample. The hysteresis loop measured by the VSM is analyzed and the JH curve, coercivity and saturation magnetization are obtained by combining the VSM software.

[0043] The JH curves of the Fe-Si-B amorphous alloys in Examples 1-6 are as follows: Figure 3As shown, the results indicate that the Fe-Si-B amorphous alloy thin strips exhibit a rapid increase in magnetic field with increasing magnetic field under low magnetic field conditions, and then gradually reach saturation, indicating that this amorphous alloy exhibits typical soft magnetic properties.

[0044] The JH curves of the amorphous alloys in Comparative Examples 1-3 are as follows: Figure 4 As shown.

[0045] The coercivity and saturation magnetization results of the amorphous alloys in Examples 1-6 and Comparative Examples 1-3 are shown in Table 1.

[0046] Table 1. Coercivity and saturation magnetization results of amorphous alloys in Examples 1-6 and Comparative Examples 1-3. Amorphous alloy Coercivity (Hc, A / m) Saturation magnetization (Ms, T) Example 1 <![CDATA[Fe 95.5 Si2B 2.5 ]]> 2.4 1.74 Example 2 <![CDATA[Fe 95.5 Yes 1.5 B3]]> 1.3 1.71 Example 3 <![CDATA[Fe 95.5 Si1B 3.5 ]]> 2.9 1.73 Example 4 <![CDATA[Fe 95 You 0.5 B 4.5 ]]> 3.1 1.69 Example 5 <![CDATA[Fe 95.8 Yes. 0.2 B4]]> 3.8 1.68 Example 6 <![CDATA[Fe 94.5 Si 3.5 B2]]> 4 1.66 Comparative Example 1 <![CDATA[Fe 94 Si4B2]]> 3.9 1.63 Comparative Example 2 <![CDATA[Fe 94 Si2B4]]> 2.3 1.61 Comparative Example 3 <![CDATA[Fe 94 Si3B3]]> 5.4 1.64 Table 1 shows that by increasing the proportions of metalloid elements Si and B, the saturation magnetization gradually increases while the coercivity significantly decreases. Compared to traditional Fe-Si-B amorphous alloys, the Fe-Si-B amorphous alloy of this invention exhibits higher saturation magnetization, lower coercivity, and superior overall soft magnetic properties. The coercivity of the Fe-Si-B amorphous alloy initially decreases and then increases with increasing proportions of Si and B; therefore, the proportions should not be too high.

[0047] As shown in Comparative Examples 1-3, increasing the proportion of metalloid elements Si and B does not necessarily improve the overall soft magnetic properties in a regular manner; it only plays a significant role within a specific range of iron content.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A Fe-Si-B iron-based amorphous alloy thin strip with high saturation magnetic induction, characterized in that, The mass percentage composition of the amorphous alloy ribbon is expressed as Fe. (100-x-y) Si x B y The value of x ranges from 0.2 to 3.5, and the value of y ranges from 2 to 4.5, satisfying: 4.2 ≤ x + y ≤ 5.

5.

2. The Fe-Si-B iron-based amorphous alloy thin strip according to claim 1, characterized in that, The amorphous alloy strip is composed of any of the following components: a) Fe 95.5 Si2B 2.5 The mass ratio of Si to B is 1:1.

25. b) Fe 95.5 Si 1.5 B3, wherein the mass ratio of Si to B is 1:2; c) Fe 95.5 Si1B 3.5 The mass ratio of Si to B is 1:3.

5.

3. A method for preparing Fe-Si-B iron-based amorphous alloy thin strips as described in any one of claims 1-2, characterized in that, Includes the following steps: S1. Alloy smelting and ingot preparation: Weigh Fe, Si, and B elemental raw materials with a purity of not less than 99.9% according to the designed composition, and place them in the crucible in the order of the lowest melting point at the bottom and the highest melting point at the top. Vacuum up to 3.5×10 -3 After the pressure drops below Pa, a protective gas is introduced until the furnace pressure reaches -0.06 MPa, all raw materials are melted, and after cooling, an alloy ingot is obtained. The alloy ingot is then turned over and melted at least once under magnetic stirring to obtain a uniform alloy ingot. S2. Single-roll melt quenching and forming: The alloy ingot obtained in step S1 is placed in a single-roll melt quenching device. Protective gas is introduced into the device under vacuum to a pressure of 400 mbar. After the alloy is melted, the molten alloy liquid drips onto the surface of the rotating cooling roller and quickly solidifies to form an amorphous alloy strip. S3. Annealing treatment: The amorphous alloy strip obtained in step S2 is annealed in a protective atmosphere at 300-400°C for 15 minutes.

4. The method according to claim 3, characterized in that, The protective gas is high-purity argon with a purity of not less than 99.95 wt%.

5. The method according to claim 3, characterized in that, The Fe, Si, and B elemental raw materials are ultrasonically cleaned sequentially with petroleum ether and anhydrous ethanol before use.

6. The method according to claim 3, characterized in that, In step S1, the melting under magnetic stirring is performed 6 times.

7. The application of Fe-Si-B iron-based amorphous alloy thin strips as described in any one of claims 1-2 in the preparation of soft magnetic materials.

8. The application according to claim 7, characterized in that, The soft magnetic material is used to manufacture high-efficiency distribution transformer cores, new energy vehicle drive motor cores, or high-frequency inductor cores.

9. The application according to claim 7, characterized in that, The soft magnetic material is used to fabricate magnetic sensor elements.

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