Nanocrystalline soft magnetic alloy and its use

Abstract

The application discloses a nanocrystalline soft magnetic alloy prepared by rapidly heat treating an amorphous precursor strip, wherein the amorphous precursor strip is composed of Fe a Si b B c P d Ni e Cu f M g , wherein a+b+c+d+e+f+g=100, M is one or two of Nb, Mo or Ta elements, 0

Description

TECHNICAL FIELD

[0001] The present application relates to the field of magnetic functional materials, in particular to a nanocrystalline soft magnetic alloy and application thereof. BACKGROUND

[0002] High saturation magnetic induction nanocrystalline material has important application value in the field of electric power and electronics due to its high energy transmission density and energy saving and environmental protection advantages. In practical applications, the saturation magnetic induction of soft magnetic material has an important influence on the size of the device, and high saturation magnetic induction is an important indicator to realize the miniaturization of the device. The soft magnetic performance of soft magnetic material determines the ferromagnetic loss of the device, which is the premise to ensure the energy efficiency and working frequency of the device. It is very important for soft magnetic material to have high saturation magnetic induction and excellent soft magnetic performance.

[0003] Iron-based nanocrystalline soft magnetic material is a new type of soft magnetic material which is obtained by crystallizing nanocrystalline grains on the amorphous matrix through heat treatment technology. Journal of Applied Physics, Vol. 64, No. 10, pp. 6044-6046, “New Fe-based soft magnetic-alloys composed of ultrafine grain-structure” discloses a FeSiBNbCu alloy (FINEMET), which is the earliest disclosed iron-based nanocrystalline soft magnetic material.

[0004] Iron-based nanocrystalline soft magnetic material has the following characteristics: (1) continuous batch production is highly feasible: continuous iron-based amorphous ribbon can be produced by using melt quenching technology, and then nanocrystalline material is obtained by crystallizing the amorphous nanomaterial through heat treatment; (2) unique microstructure: iron-based nanocrystalline alloy has a dual-phase structure composed of α-Fe nanocrystalline phase and residual amorphous phase with a size of less than 50 nm, which is uniformly distributed and has strong magnetic exchange coupling; (3) excellent comprehensive soft magnetic performance: the saturation magnetic induction mainly depends on the composition, while the soft magnetic performance (coercivity, permeability, etc.) is greatly affected by the microstructure, and iron-based nanocrystalline soft magnetic material has the characteristics of high magnetic induction, low coercivity and high permeability.

[0005] Iron-based nanocrystalline soft magnetic alloy is praised as a new type of “double green energy-saving strategic new material” due to its excellent performance. FINEMET type alloy has been industrialized, replacing permalloy, soft magnetic ferrite and cobalt-based amorphous alloy, and has been widely used in the field of high-frequency power electronics and electronic information.

[0006] To further improve the saturation magnetic induction of Fe-based nanocrystalline soft magnetic material, make it more suitable for power applications, and promote the development of device miniaturization, researchers have carried out a lot of research. The patent with the publication number US 5449419 B discloses a Fe-M-B-Cu (M is Zr, Hf or Nb, etc.) alloy (NANOPERM) with high magnetic flux density (1.5-1.7T) and high permeability. However, it contains a large amount of pre-transition metal elements, which are expensive and easy to oxidize, and need to be prepared in a vacuum. It has not been widely used so far.

[0007] The patent with the publication number CN 102741437 B discloses a Fe-Si-B-P-(C)-Cu system NANOMET alloy, which has a magnetic induction of more than 1.8T and a minimum coercivity of 7A / m. However, its maximum coercivity can reach 100A / m, and the strip-making process and heat treatment conditions are relatively high. It has not been widely used so far.

[0008] High-saturation magnetic nanocrystalline materials often have high iron content. If the heating rate is low during the crystallization process of amorphous precursor heat treatment, iron grains are easy to grow, and the soft magnetic properties will deteriorate. Fast heating heat treatment process can effectively achieve extremely high nucleation rate in amorphous alloys with a saturation magnetic induction of more than 1.75T, which is the key to the industrial production and wide application of high-saturation magnetic nanocrystalline alloys.

[0009] The patent with the publication number CN 107532267 B discloses a nanocrystalline magnetic alloy, which is FeCuxBySizAaXb, the atomic percentage of each element is 0.6≤x<1.2, 10≤y≤20, 0<z≤10, 0≤(y+z)≤24, 0≤a≤10, 0≤b≤5, the rest is Fe and incidental impurities, wherein A is selected from at least one element of Ni, Mn, Co, V, Cr, Ti, Zr, Nb, Mo, Hf, Ta or W, and X is selected from at least one element of Re, Y, Zn, As, In, Sn or rare earth elements. The heat treatment method is to heat the nanocrystalline alloy strip from room temperature or higher temperature to a predetermined holding temperature in the range of 430-530℃ at an average heating rate of more than 50℃ / s, the combined duration of heating and holding is 3-15 seconds, the obtained alloy has a saturation magnetic induction of more than 1.7T and a coercivity of less than 6.5A / m, and the magnetic core loss at 1.5T and 50Hz is less than 0.27W / kg.

[0010] The patent with the publication number CN 109844873 B discloses a nanocrystalline soft magnetic material with high saturation magnetization and low coercivity (HiBperm) and a manufacturing method. The molecular formula of the material is Fe 100-x-y Bx M y and Fe 100-a-b- c B a Cu b M c , M is one element of Nb, Mo, Ta, W, Ni, Co and Sn, wherein the atomic percentage of each element is 10≤x≤16, 0≤y≤8, 10≤a≤16, 0<b≤2, 0≤c≤8. The amorphous phase alloy with the above composition is heated at a heating rate of 125℃ / s or more, and kept at a temperature above the crystallization initiation temperature and below the initiation temperature of Fe-B compound formation for 0-17s, to obtain a nanocrystalline alloy with a saturation magnetic induction of 1.75T or more and a coercivity of 1.4-19A / m.

[0011] Although the above prior art heat treatment process has the feasibility of continuous production of iron-based nanocrystalline alloy, the heat treatment time window is extremely short, less than 20s, and the temperature range required to achieve optimal soft magnetic properties is small, which is difficult to control in the production process, and the preferred properties are not easy to maintain.

[0012] The current existing high saturation magnetic induction nanocrystalline soft magnetic alloy (B s ≥1.75T) has a high iron content in its composition, poor glass forming ability, and a very thin strip thickness required to achieve the critical cooling rate, which is difficult to meet in industrial technology, resulting in poor strip quality and affecting the soft magnetic properties. In addition, high heating rate heat treatment is a prerequisite to ensure the soft magnetic properties of high saturation magnetic induction nanocrystalline soft magnetic alloy, but the alloy based on this technology has a narrow optimal heat treatment window, high control difficulty in the production process, and it is difficult to achieve the preferred properties stably.

[0013] In view of the shortcomings of the above prior art, it is particularly important to develop a new type of iron-based nanocrystalline alloy material based on high heating rate heat treatment technology, which is suitable for current industrial strip production technology, has high saturation magnetic induction, excellent soft magnetic properties, and a wide optimal heat treatment temperature and time window. SUMMARY

[0014] To overcome the defects of low amorphous forming ability, poor soft magnetic properties, and high heat treatment control difficulty of the existing high saturation magnetic induction nanocrystalline soft magnetic alloy, the present application provides a nanocrystalline soft magnetic alloy, which has high saturation magnetic induction, low coercivity, excellent soft magnetic alloy properties and stable quality, and its preparation method is simple and suitable for industrial application.

[0015] A nanocrystalline soft magnetic alloy prepared by rapid heat treatment of an amorphous precursor strip, the composition of the amorphous precursor strip is Fe a Si b B c P d Nie Cu f M g wherein a+b+c+d+e+f+g=100, M is one or two of Nb, Mo or Ta element, 0<f≤1.8, 0.4≤g≤2, 1≤e / f≤3.

[0016] Preferably, the atomic percentage of each element in the amorphous precursor strip is: 77≤a≤83, 3≤b≤5, 6≤c≤12, 2≤d≤5, 0.8≤e≤3, 0.8≤f≤1.8, 0.4≤g≤2.

[0017] The present application adopts higher Fe and Ni content to ensure the saturation magnetic induction of the alloy, adopts a certain atomic percentage of B, P, Ni and Mo, Nb and Ta elements to ensure the amorphous forming ability of the alloy, controls the content of Si, Cu and Mo, Nb and Ta to adjust the kinetic parameters of the alloy crystallization, ensures the soft magnetic properties of the alloy through high heating rate heat treatment, and further improves the soft magnetic properties of the alloy through reasonable addition of Ni and Cu.

[0018] Preferably, the amorphous precursor strip is prepared from alloy raw materials with the above composition by melt quenching method. The amorphous precursor strip prepared by the present application has smooth surface and neat edge, and the toughness meets the requirement that it will not be broken after being folded by 180°.

[0019] On the basis of high Fe content, the present application improves the amorphous forming ability of the alloy material through reasonable regulation and control of non-metallic elements B and P and the content of doped Ni and front transition metal Nb, Mo or Ta, and the amorphous forming ability meets the requirement of forming 17-20um thick amorphous strip, which is lower than the industrial index and is not difficult to manufacture.

[0020] Preferably, the amorphous precursor strip is completely amorphous or has partial nanocrystalline grains. The free surface of the amorphous precursor strip with partial nanocrystalline grains has a crystallization layer.

[0021] The present application can prepare nanocrystalline soft magnetic alloy through rapid heat treatment on the premise that the amorphous precursor strip has a crystallization layer, and the obtained alloy has excellent soft magnetic properties, which reduces the requirement for the quality of the amorphous strip and improves the stability of product quality.

[0022] Preferably, the rapid heat treatment is to heat the amorphous precursor strip to 450-550℃ at an average heating rate of 100-5000℃ / s, and the holding time is 5-600s. The temperature window of the rapid heat treatment is 30-60℃, and the time window is 600-60s.

[0023] Compared with the same kind of rapid heating treatment (heating rate ≥10℃ / s), the application can keep the optimal performance combination of the nanocrystalline soft magnetic alloy in a wider heat treatment temperature window and time window, reduces the control precision requirement in the rapid heat treatment process, improves the stability of product quality, and is suitable for industrial application.

[0024] The application controls the content of Si and Nb, Mo and Ta in the alloy raw material, and simultaneously adds Ni and Cu and controls the ratio of the two, adjusts the kinetic characteristics of the primary crystallization and secondary crystallization of the alloy, refines the microstructure of the nanocrystalline alloy, and ensures that the structure and performance of the alloy remain stable in a larger heat treatment temperature and time window.

[0025] Preferably, the saturation magnetic induction of the nanocrystalline soft magnetic alloy is ≥1.75T, the coercive force is ≤3.9A / m, the effective permeability at 1kHz, 1A / m is >9600, and the average grain size is 12-18nm.

[0026] More preferably, the average grain size of the nanocrystalline soft magnetic alloy is 12-15nm.

[0027] Preferably, when the composition of the nanocrystalline soft magnetic alloy is Fe 82 Ni1Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu1, the coercive force of the nanocrystalline soft magnetic alloy is ≤2.8A / m, the saturation magnetic induction is ≥1.79T, and the effective permeability at 1kHz, 1A / m is >9600 in a 30℃ wide temperature window of 460-490℃ for 5-600s.

[0028] Preferably, when the composition of the nanocrystalline soft magnetic alloy is Fe 81.7 Ni 1.5 Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu 0.8 , the coercive force of the nanocrystalline soft magnetic alloy is ≤2A / m, the saturation magnetic induction is ≥1.81T, and the effective permeability at 1kHz, 1A / m is >10500 in a 40℃ wide temperature window of 480-520℃ for 5-60s.

[0029] Preferably, when the composition of the nanocrystalline soft magnetic alloy is Fe 82 Ni1Si3B 8.4 P 3.6When Nb1Cu1, the nanocrystalline soft magnetic alloy has coercivity ≤3.4 A / m and saturation magnetic induction ≥1.75 T when being kept in a temperature window of 470-520 ℃ with a width of 50 ℃ for 5-60 s.

[0030] Preferably, when the nanocrystalline soft magnetic alloy has the composition of Fe 80 Ni 2.8 Si2B 8.4 P 3.6 Nb2Cu 1.2 When Nb1Cu1, the nanocrystalline soft magnetic alloy has coercivity ≤3.4 A / m and saturation magnetic induction ≥1.75 T when being kept in a temperature window of 470-520 ℃ with a width of 50 ℃ for 5-60 s.

[0031] The application also provides an application of the nanocrystalline soft magnetic alloy in a transformer soft magnetic core, an inductance coil magnetic core and a motor stator core.

[0032] Compared with the prior art, the application has at least the following beneficial effects:

[0033] 1. The application solves the problem that the nanocrystalline material cannot simultaneously have high saturation magnetic induction and excellent soft magnetic performance and is difficult to manufacture in industry by designing alloy components and adopting a rapid heat treatment scheme.

[0034] 2. The alloy components designed in the application can have excellent soft magnetic performance after heat treatment on the premise that there is a crystallization layer on the surface, reduce the requirement for the quality of amorphous strips and improve the stability of product quality.

[0035] 3. The application can maintain the optimal performance combination of the nanocrystalline soft magnetic alloy in a wider heat treatment temperature and time window, reduce the requirement for control precision in the rapid heat treatment process and is suitable for industrial application.

[0036] 4. The alloy components have high content of ferromagnetic elements (Fe, Ni), and the saturation magnetic induction after nanocrystallization can be ensured to be above 1.75 T, and the optimal components can be ensured to be above 1.8 T, which is in the forefront in terms of high saturation magnetic induction.

[0037] 5. The nanocrystalline soft magnetic alloy prepared by this invention maintains a high saturation magnetic induction (≥1.75T) while its coercivity can be stably below 4A / m. Its optimal composition can achieve a saturation magnetic induction ≥1.80T, while maintaining a coercivity stably below 2A / m, approaching the level of FINEMET alloys known for their soft magnetic properties. Its performance combination is leading among high-saturation magnetic induction nanocrystalline alloys. Attached Figure Description

[0038] Figure 1 The heating rate is the rate of increase in the rapid heat treatment process in Example 1;

[0039] Figure 2 The XRD diffraction pattern of the amorphous precursor ribbon prepared in Example 1;

[0040] Figure 3 The image shows a transmission electron microscope (TEM) image of the amorphous precursor ribbon prepared in Example 1.

[0041] Figure 4 The microstructure of the nanocrystalline soft magnetic alloy prepared under the conditions of rapid heat treatment at 500°C and holding time of 5s in Example 1 is shown. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Modifications or equivalent substitutions made by those skilled in the art based on their understanding of the technical solutions of this invention, without departing from the spirit and scope of the invention, should be covered within the protection scope of this invention.

[0043] Example 1

[0044] The alloy composition of this embodiment is Fe. 82 Ni1Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu1 is prepared using commercially available high-purity raw materials, including pure iron, pure nickel, pure silicon, iron-boron alloy, iron-phosphorus alloy, pure molybdenum, and pure copper. The raw materials conforming to the above alloy composition ratios are vacuum-melted to prepare a master alloy ingot. The resulting master alloy ingot is then processed into a completely amorphous or free-faced amorphous precursor strip using a rapid melt quenching method. The amorphous precursor strip is then subjected to rapid heat treatment under the following conditions: an average heating rate of 823℃ / s (e.g., ...). Figure 1The temperature was raised to 470℃, 480℃, 490℃, 500℃, 510℃ and 520℃ respectively, and then held for different holding times of 5s, 60s, 300s and 600s respectively. After the holding time was completed, the temperature was cooled to room temperature to obtain nanocrystalline soft magnetic alloy.

[0045] XRD analysis was performed on the amorphous precursor ribbon prepared in this embodiment, and its XRD diffraction pattern was obtained. Figure 2 ). Figure 2 This embodiment shows that the roll-mounted surface of the amorphous precursor strip prepared in this example is completely amorphous, while its free surface has a crystalline layer. Observation of the crystalline layer on the free surface of the strip using a transmission electron microscope reveals that the grain size of the crystalline layer can reach 28 nm (e.g., ...). Figure 3 ).

[0046] The performance of the nanocrystalline soft magnetic alloy prepared in this embodiment was tested, and the test results are shown in Tables 1-3. As shown in Tables 1-3, when held at a temperature window of 460-510℃ (50℃) for 5-60s, the obtained nanocrystalline soft magnetic alloy exhibits a coercivity ≤2.6A / m, a saturation magnetic induction ≥1.79T, and an effective permeability >9600 under test conditions of 1kHz and 1A / m. When held at a temperature window of 40℃ (460-500℃) for 5-300s, the obtained nanocrystalline soft magnetic alloy exhibits a coercivity ≤2.8A / m, a saturation magnetic induction ≥1.79T, and an effective permeability >9600 under test conditions of 1kHz and 1A / m. When held at a temperature window of 30℃ (460-490℃) for 5-600s, the obtained nanocrystalline soft magnetic alloy exhibits a coercivity ≤2.8A / m, a saturation magnetic induction ≥1.79T, and an effective permeability >9600 under test conditions of 1kHz and 1A / m.

[0047] Table 1. Coercivity values ​​of the nanocrystalline soft magnetic alloys prepared in Example 1

[0048] Coercivity (A / m) 5s 60s 300s 600s 460℃ 2.0 2.6 2.8 2.7 470℃ 1.5 1.6 2.4 2.7 480℃ 1.6 1.6 1.3 2.7 490℃ 1.5 1.6 2.0 2.2 500℃ 1.6 2.0 1.3 4.5 510℃ 1.9 2.1

[0049] Table 2. Saturation magnetic induction values ​​of the nanocrystalline soft magnetic alloys prepared in Example 1

[0050] Saturation magnetic induction (T) 5s 60s 300s 600s 460℃ 1.79 1.81 1.80 1.82 470℃ 1.83 1.79 1.82 1.81 480℃ 1.81 1.81 1.79 1.82 490℃ 1.84 1.81 1.80 1.83 500℃ 1.84 1.82 1.81 1.84 510℃ 1.82 1.83

[0051] Table 3 Effective magnetic permeability of the nanocrystalline soft magnetic alloys prepared in Example 1

[0052] Initial relative magnetic permeability 5s 60s 300s 600s 460℃ 9683 10432 10065 9766 470℃ 9987 10816 11096 9998 480℃ 11038 10207 10819 10584 490℃ 10684 11153 10387 11257 500℃ 12173 9923 10123 8972 510℃ 11083 10684

[0053] It can be seen that, compared with the alloys disclosed in the prior art, the soft magnetic alloy prepared in the embodiment has higher saturation magnetic induction and lower coercivity, and the heat treatment temperature window and time window are significantly wider while maintaining the optimal performance of the alloy, and the manufacturing difficulty is lower.

[0054] Figure 4 The microstructure of the nanocrystalline soft magnetic alloy prepared under the condition of a rapid heat treatment temperature of 500℃ and a holding time of 5s is shown. It can be seen that the grain distribution of the nanocrystalline soft magnetic alloy prepared under this condition is uniform, and the average size is 13.1nm. The fine and uniform nanocrystalline structure ensures excellent soft magnetic performance of the alloy.

[0055] Example 2

[0056] The alloy composition of the embodiment is Fe 81.7 Ni 1.5 Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu 0.8 The raw materials used for preparation are all commercially available high-purity raw materials, including pure iron, pure nickel, pure silicon, iron boron alloy, iron phosphorus alloy, pure molybdenum and pure copper. The raw materials meeting the above alloy composition ratio are vacuum melted to prepare a mother alloy ingot, and the mother alloy ingot obtained by melting is prepared into an amorphous precursor strip with complete amorphous or free surface with nanocrystalline grains by melt quenching method. The amorphous precursor strip is treated by rapid heat treatment method, and the conditions of rapid heat treatment are as follows: heating to 470℃, 480℃, 490℃, 500℃, 510℃, 520℃ at an average heating rate of 4000℃ / s, and then holding at different holding times, the holding times are 5s, 60s and 300s respectively, and then cooling to room temperature to obtain a nanocrystalline soft magnetic alloy.

[0057] Table 4 Coercivity value of the nanocrystalline soft magnetic alloy prepared in Example 2

[0058] Coercivity (A / m) 5s 60s 300s 470℃ 2.8 2.7 2.9 480℃ 1.2 1.7 1.6 490℃ 0.8 1.5 2.2 500℃ 1.0 1.8 2.7 510℃ 0.7 2.0 520℃ 1.6 1.9 530℃ 1.4 3.0

[0059] The nanocrystalline soft magnetic alloy prepared in the embodiment was subjected to performance testing, and the test results are shown in Tables 4-6. As shown in Tables 4-6, when the temperature window is 470-530℃ for a total of 60℃ and the holding time is 5-60s, the coercivity of the obtained nanocrystalline soft magnetic alloy is ≤3.0A / m, the saturation magnetic induction is ≥1.80T, and the effective permeability under the test condition of 1kHz, 1A / m is >9900; when the temperature window is 470-500℃ for a total of 30℃ and the holding time is 5-300s, the coercivity of the obtained nanocrystalline soft magnetic alloy is ≤2.9A / m, the saturation magnetic induction is ≥1.80T, and the effective permeability under the test condition of 1kHz, 1A / m is >9600. Especially when the temperature window is 480-520℃ for a total of 40℃ and the holding time is 5-60s, the performance of the obtained nanocrystalline soft magnetic alloy is very stable, at this time the coercivity of the alloy is ≤2A / m, the minimum is 0.7A / m, the saturation magnetic induction is ≥1.81T, and the effective permeability under the test condition of 1kHz, 1A / m is >10500.

[0060] Table 5: Saturation magnetic induction value of the nanocrystalline soft magnetic alloy prepared in Example 2

[0061] Saturation magnetic induction (T) 5s 60s 300s 470℃ 1.80 1.80 1.82 480℃ 1.81 1.81 1.80 490℃ 1.81 1.82 1.81 500℃ 1.82 1.81 1.82 510℃ 1.81 1.81 520℃ 1.83 1.82 530℃ 1.82 1.81

[0062] Table 6: Effective permeability value of the nanocrystalline soft magnetic alloy prepared in Example 2

[0063] Initial relative magnetic permeability 5s 60s 300s 470℃ 9918 10523 9673 480℃ 11932 10764 11042 490℃ 10983 10776 11059 500℃ 11782 11083 510℃ 12105 10583 520℃ 10514 10781

[0064] Example 3

[0065] The alloy composition of the embodiment is Fe 82 Ni1Si3B 8.4 P 3.6 Nb1Cu1, and the raw materials used for preparation are all commercially available high-purity raw materials, including pure iron, pure nickel, pure silicon, iron boron alloy, iron phosphorus alloy, pure niobium and pure copper. The raw materials meeting the above alloy composition ratio are vacuum melted to prepare a mother alloy ingot, and the mother alloy ingot obtained by melting is prepared into an amorphous precursor strip with complete amorphous or free surface with nanocrystalline grains by melt quenching method. The amorphous precursor strip is treated by rapid heat treatment method, and the rapid heat treatment conditions are: heating to 470℃, 480℃, 490℃, 500℃, 510℃, 520℃ at an average heating rate of 4000℃ / s, and then holding for different holding times, the holding times are 5s and 60s respectively, and then cooling to room temperature to obtain a nanocrystalline soft magnetic alloy.

[0066] The nanocrystalline soft magnetic alloy prepared in the embodiment was subjected to performance test, and the test results are shown in Tables 7-8. The nanocrystalline soft magnetic alloy prepared can stably maintain coercivity ≤ 3.9 A / m and saturation magnetic induction ≥ 1.75 T when being kept at a temperature window of 470-510 ℃ with a width of 40 ℃ for 5-300 s. The nanocrystalline soft magnetic alloy prepared can stably maintain coercivity ≤ 3.4 A / m and saturation magnetic induction ≥ 1.75 T when being kept at a temperature window of 470-520 ℃ with a width of 50 ℃ for 5-60 s.

[0067] Table 7 Coercivity values of the nanocrystalline soft magnetic alloy prepared in Example 3

[0068] Coercivity (A / m) 5s 60s 300s 470℃ 2.3 3.4 3.9 480℃ 2.1 2.7 3.4 490℃ 1.8 2.6 3.4 500℃ 2.6 2.4 3.6 510℃ 2.8 2.7 3.4 520℃ 2.8 3.2 5.2 530℃ 2.9 4.4 8.8 540℃ 3.0 6.2 11.2

[0069] Table 8 Saturation magnetic induction values of the nanocrystalline soft magnetic alloy prepared in Example 3

[0070] Saturation magnetic induction (T) 5s 60s 300s 470℃ 1.75 1.76 1.77 480℃ 1.75 1.77 1.76 490℃ 1.76 1.76 1.77 500℃ 1.77 1.77 1.78 510℃ 1.76 1.77 1.78 520℃ 1.77 1.78 530℃ 1.76 1.77

[0071] Example 4

[0072] The alloy composition of the embodiment is Fe 80 Ni 2.8 Si2B 8.4 P 3.6 Nb2Cu 1.2 The raw materials used for preparation are all commercially available high-purity raw materials, including pure iron, pure nickel, pure silicon, iron boron alloy, iron phosphorus alloy, pure niobium and pure copper. The raw materials meeting the above alloy composition ratio are vacuum melted to prepare a mother alloy ingot, and the mother alloy ingot obtained by melting is prepared into an amorphous precursor strip with complete amorphous or free surface with nanocrystalline grains by melt quenching method. The amorphous precursor strip is treated by rapid heat treatment method, and the conditions of rapid heat treatment are as follows: heating to 470 ℃, 480 ℃, 490 ℃, 500 ℃, 510 ℃, 520 ℃ at an average heating rate of 4000 ℃ / s, and then keeping at different holding times, the holding times are 5 s and 60 s respectively, and then cooling to room temperature to obtain a nanocrystalline soft magnetic alloy.

[0073] Table 9 Coercivity values of the nanocrystalline soft magnetic alloy prepared in Example 4

[0074] Coercivity (A / m) 5s 60s 300s 470℃ 2.7 2.8 3.0 480℃ 2.8 2.7 2.8 490℃ 2.1 2.5 2.7 500℃ 2.6 2.4 510℃ 2.8 2.6 520℃ 2.8 2.8 530℃ 2.9 3.0 540℃ 3.0 2.9

[0075] Table 10 Saturation magnetic induction values of the nanocrystalline soft magnetic alloy prepared in Example 4

[0076] Saturation magnetic induction (T) 5s 60s 300s 470℃ 1.75 1.75 1.76 480℃ 1.75 1.76 1.76 490℃ 1.76 1.77 1.76 500℃ 1.76 1.76 510℃ 1.75 1.76 520℃ 1.76 1.77 530℃ 1.76 1.76

[0077] As shown in Tables 9-10, the coercivity of the obtained nanocrystalline soft magnetic alloy is ≤3.0 A / m, and the saturation magnetic induction is ≥1.75 T when the temperature window is 60 ℃ wide and the holding time is 5-60 s at 470-530 ℃; the coercivity of the obtained nanocrystalline soft magnetic alloy is ≤3.0 A / m, and the saturation magnetic induction is ≥1.75 T when the temperature window is 20 ℃ wide and the holding time is 5-300 s at 470-490 ℃.

[0078] The above-described embodiments are merely preferred modes of the present application, and are not intended to limit the scope of the present application. Various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art without departing from the design spirit of the present application shall fall within the protection scope of the present application as defined by the claims.

Claims

1. A nanocrystalline soft magnetic alloy characterized by, Prepared from an amorphous precursor strip by rapid thermal processing, the composition of the amorphous precursor strip being Fe a Si b B c P d Ni e Cu f M g wherein a+b+c+d+e+f+g=100, M is one or two of the elements Nb, Mo or Ta, 77 ≤ a ≤ 83, 3 ≤ b ≤ 5, 6 ≤ c ≤ 12, 2 ≤ d ≤ 5, 0.8 ≤ e ≤ 3, 0.8 ≤ f ≤ 1.8, 0.4 ≤ g ≤ 2; The rapid heat treatment is heating the amorphous precursor strip to 450-550 ℃ at an average heating rate of 100-5000 ℃ / s, and holding for 5-600 s, the temperature window of the rapid heat treatment is 30-60 ℃, and the time window is 600-60 s. The nanocrystalline soft magnetic alloy has a saturation magnetic induction ≥ 1.75 T, a coercive force ≤ 3.9 A / m, an effective magnetic permeability > 9600 at 1 kHz and 1 A / m, and an average grain size of 12-18 nm.

2. The nanocrystalline soft magnetic alloy of claim 1, wherein The amorphous precursor strip is completely amorphous or has partial nanocrystalline grains.

3. The nanocrystalline soft magnetic alloy of claim 1, wherein, When the composition of the nanocrystalline soft magnetic alloy is Fe 82 Ni1Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu1, the coercivity of the nanocrystalline soft magnetic alloy is ≤ 2.8 A / m, the saturation magnetic induction is ≥ 1.79 T, and the effective permeability at 1 kHz, 1 A / m is > 9600 within a temperature window of 460-490 ℃, a total of 30 ℃, and a holding time of 5-600 s.

4. The nanocrystalline soft magnetic alloy of claim 1, wherein, When the composition of the nanocrystalline soft magnetic alloy is Fe 81.7 Ni 1.5 Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu 0.8 When the composition of the nanocrystalline soft magnetic alloy is Fe 81.7 Ni 1.5 Si 3.6 B 8.4 P 3.6 Mo 0.4 Cu 0.8 , and the nanocrystalline soft magnetic alloy is kept at a temperature window of 480-520 ℃, which is 40 ℃ in total, for 5-60 s, the coercivity of the nanocrystalline soft magnetic alloy is ≤ 2 A / m, the saturation magnetic induction is ≥ 1.81 T, and the effective permeability at 1 kHz, 1 A / m is > 10500.

5. The nanocrystalline soft magnetic alloy of claim 1, wherein, When the composition of the nanocrystalline soft magnetic alloy is Fe 82 Ni1Si3B 8.4 P 3.6 Nb1Cu1, the coercivity of the nanocrystalline soft magnetic alloy is ≤ 3.4 A / m, and the saturation magnetic induction is ≥ 1.75 T when annealing at a temperature window of 470-520 ℃, a total of 50 ℃, for 5-60 s.

6. The nanocrystalline soft magnetic alloy of claim 1, wherein When the composition of the nanocrystalline soft magnetic alloy is Fe 80 Ni 2.8 Si2B 8.4 P 3.6 Nb2Cu 1.2 When the composition of the nanocrystalline soft magnetic alloy is Fe 80 Ni 2.8 Si2B 8.4 P 3.6 Nb2Cu 1.2 , and annealing at a temperature window of 470-530 ℃, which is 60 ℃ in total, for 5-60 s, the coercivity of the nanocrystalline soft magnetic alloy is ≤ 3.0 A / m, and the saturation magnetic induction is maintained at ≥ 1.75 T.

7. Application of the nanocrystalline soft magnetic alloy according to any one of claims 1-6 in a transformer soft magnetic core, an inductor magnetic core, and a motor stator core.

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