A high-permeability, high-impedance manganese-zinc ferrite material for high-frequency applications and its preparation method.

Abstract

This invention belongs to the technical field of soft magnetic ferrite ceramic materials, specifically relating to a high-permeability, high-impedance manganese-zinc ferrite material for high frequencies and its preparation method. The high-permeability, high-impedance manganese-zinc ferrite material for high frequencies comprises a main component and trace additives: the main component, based on oxides, consists of Fe₂O₃ 48.0-52.0 mol%, MnO₂ 31.0-33.0 mol%, with the balance being ZnO; the trace additives, based on the weight of the main component, consist of the following components: CaO 200-700 ppm, CoO 2000-4000 ppm, MoO 200-400 ppm, Bi₂O₃ 300-500 ppm, and Nb₂O₅ 20-100 ppm. The manganese-zinc ferrite material provided by this invention possesses high saturation magnetic flux density, high initial permeability, high impedance at high frequencies, and a high Curie temperature.

Description

Technical Field

[0001] This invention belongs to the technical field of soft magnetic ferrite ceramic materials, specifically relating to a high-permeability, high-impedance manganese-zinc ferrite material for high frequencies and its preparation method. Background Technology

[0002] Soft magnetic ferrites are non-metallic functional ceramic materials widely used in the electronics industry. Modern electronic devices not only strive for miniaturization and weight reduction in their design, but also require optimized electronic properties to meet the demands of high performance and high stability. However, with the increasing density of electronic components and the rise in design frequencies, electromagnetic interference (EMI) has gradually become a challenge that cannot be ignored. As component size shrinks and operating frequencies increase, the electromagnetic coupling effect within the system intensifies, leading to more severe EMI. This not only causes signal noise and system instability, but may even cause frequency resonance with surrounding components, further affecting the overall reliability and lifespan of the circuit.

[0003] Electromagnetic compatibility (EMC) design is considered the most effective solution to this problem. Its core lies in using materials with excellent electromagnetic suppression capabilities to reduce or shield the negative impact of electromagnetic interference on electronic devices. Among many materials, manganese-zinc ferrite, with its combination of high permeability and high impedance, has become a key choice for solutions. This material can effectively suppress high-frequency noise and plays an indispensable role in power management, signal transmission, and high-performance computing.

[0004] As electronic components continue to develop towards miniaturization, high power density, and high frequency, the requirements for the performance of manganese zinc ferrites are also increasing. How to further develop manganese zinc ferrites that combine high saturation magnetic flux density, high permeability, and high-frequency impedance characteristics has become an important research topic in materials science and the electronics industry.

[0005] The inventors previously developed a high-Tc, high-frequency, and high-impedance MnZn ferrite material and applied for a related patent, publication number CN118791295A. In this technical solution, the MnZn ferrite is formed by multi-stage sintering of the main components and auxiliary modifiers. The main components consist of iron oxide, zinc oxide, and manganese oxide, while the auxiliary modifiers consist of calcium carbonate, silicon dioxide, tin oxide, and other metal oxides. By performing multi-stage sintering of the main components and auxiliary modifiers, uniform grain growth is promoted during the ferrite sintering process, reducing the grain size range of the ferrite grains, improving the uniformity of the ferrite grain size distribution, and enhancing the impedance performance of the ferrite. It has the advantages of high Curie temperature, high permeability, strong impedance performance, and suitability for high-temperature use scenarios during automotive operation, making it easy to promote and implement. However, this technical solution is applicable to the 1MHz-2MHz frequency range, while some existing manganese-zinc ferrite materials have been applied to the high-frequency range of 10MHz and above. Therefore, the inventors have conducted further research and development on manganese-zinc ferrite materials.

[0006] The inventors have discovered that although existing manganese-zinc ferrite materials used in high-frequency applications have high impedance at high frequencies, they suffer from low permeability (generally around 2000-3000) or low Curie temperature. This is because the Curie temperature decreases as the permeability of the ferrite material increases, making it difficult to simultaneously increase both permeability and Curie temperature. This technical problem is also a problem that urgently needs to be solved in this field.

[0007] For example, Chinese patent CN111892395B discloses a high-frequency, high-impedance manganese-zinc ferrite material and its preparation method. Its main components, calculated as oxides, consist of Fe2O3: 48-49.7 mol%, MnO: 29-33 mol%, ZnO: 19-21 mol%, and Co2O3: 0.03-0.08 mol%. The secondary components, by weight of the main components, include at least three of the following: Nb2O5: 0.01-0.05 wt%, CaCO3: 0.02-0.05 wt%, SnO2: 0.01-0.08 wt%, Bi2O3: 0.01-0.06 wt%, and MoO3: 0.01-0.05 wt%. The manganese-zinc ferrite material of this technical solution has a permeability of approximately 3000, and impedances of over 50 Ω and approximately 125 Ω at 25 MHz and 100 MHz, respectively, but the Curie temperature is between 130℃ and 140℃.

[0008] Chinese patent application CN120887716A discloses a manganese-zinc ferrite high-frequency high-impedance material and its preparation process. The raw materials for preparing the manganese-zinc ferrite high-frequency high-impedance material include Fe2O3, Mn3O4, ZnO, carbon nanotube-supported rare earth oxide composite material, P2O5, Co2O3, and CaCO3. The raw materials for preparing the carbon nanotube-supported rare earth oxide composite material include multi-walled carbon nanotubes and rare earth salts, with a mass ratio of multi-walled carbon nanotubes to rare earth salts of 1:(0.12-0.14). The manganese-zinc ferrite material of this technology exhibits impedances of over 50Ω at 25MHz and over 130Ω at 100MHz, with a Curie temperature of around 160℃. However, its permeability is only around 2000. Furthermore, this technology requires the use of a specific carbon nanotube-supported rare earth oxide composite material, resulting in a complex preparation process and limiting its industrial-scale mass production.

[0009] In addition, some manganese-zinc ferrite materials use highly toxic V2O5 in their formulations, which does not meet environmental protection requirements and limits the application of such manganese-zinc ferrite materials. Summary of the Invention

[0010] In order to overcome the shortcomings and deficiencies of the prior art, the primary objective of this invention is to provide a high-permeability, high-impedance manganese-zinc ferrite material for high frequencies.

[0011] Another objective of this invention is to provide a method for preparing high-permeability, high-impedance manganese-zinc ferrite materials at high frequencies.

[0012] The objective of this invention is achieved through the following solution:

[0013] A high-permeability, high-impedance manganese-zinc ferrite material for high-frequency applications, comprising a main component and trace additives: the main component, based on oxides, consists of Fe2O3 48.0-52.0 mol%, MnO2 31.0-33.0 mol%, with the balance being ZnO; the trace additives, based on the weight of the main component, consist of the following components: CaO 200-700 ppm, CoO 2000-4000 ppm, MoO 200-400 ppm, Bi2O3 300-500 ppm, and Nb2O5 20-100 ppm.

[0014] Furthermore, the main components, calculated as oxides, consist of 49.0-52.0 mol% Fe2O3, 31.0-33.0 mol% MnO2, with the balance being ZnO.

[0015] Furthermore, the main components, calculated as oxides, consist of 50.0-51.0 mol% Fe2O3, 31.0-32.0 mol% MnO2, with the balance being ZnO.

[0016] Furthermore, in the trace additive, the mass ratio of CoO, Bi2O3 and CaO is 15-20:1-2:1.

[0017] Furthermore, the high-permeability, high-impedance manganese-zinc ferrite material for high frequency comprises a main component and trace additives: the main component, calculated as oxides, consists of 50.0-51.0 mol% Fe2O3, 31.0-32.0 mol% MnO2, with the balance being ZnO; the trace additives, by weight of the main component, consist of the following components: 200 ppm CaO, 3500 ppm CoO, 300 ppm MoO, 300 ppm Bi2O3, and 50 ppm Nb2O5.

[0018] A method for preparing high-permeability, high-impedance manganese-zinc ferrite materials for high frequencies includes the following steps:

[0019] Step S1: Mix the main components according to the ratio, calcine, and obtain calcined powder;

[0020] Step S2: Mix the calcined powder, trace additives, water and PVA (polyvinyl alcohol) to obtain a slurry;

[0021] Step S3: The slurry is ball-milled, and after ball milling, the slurry is spray-granulated to obtain ferrite particles;

[0022] Step S4: Compact the ferrite particles to obtain a green embryo;

[0023] Step S5: Perform staged sintering on the green blank to obtain a high permeability and high impedance manganese zinc ferrite material.

[0024] Further, the calcination temperature in step S1 is 900-1000℃, for example, it can be 900℃, 910℃, 920℃, 930℃, 940℃, 950℃, 960℃, 970℃, 980℃, 990℃ or 1000℃; preferably 900-920℃; the calcination time is 1-6h, for example, it can be 1h, 2h, 3h, 4h, 5h or 6h, preferably 2h.

[0025] Further, the mass ratio of the calcined powder to water in step S2 is 4-7:3, for example, it can be 4:2, 5:3, 6:3 or 7:3, preferably 5:3.

[0026] Further, the amount of PVA used in step S2 is 0.8-1.2 wt% of the calcined powder, for example, it can be 0.8 wt%, 0.9 wt%, 1.0 wt%, 1.1 wt% or 1.2 wt%, preferably 0.9 wt%.

[0027] Furthermore, the ball milling medium in step S3 is steel balls, with a size of 1 / 4 inch.

[0028] Furthermore, after ball milling in step S3, the particle size of the powder in the slurry is 1.0-2.0 μm.

[0029] Furthermore, the density of the embryo described in step S4 is 3.3 ± 0.2 g / cm³. 3 .

[0030] Furthermore, the staged sintering described in step S5 includes a heating stage, a isothermal stage, and a cooling stage.

[0031] Furthermore, the heating stage specifically involves heating at a rate of 2.5-4℃ / min. When the temperature reaches 800-900℃, the air intake valve is closed, and the nitrogen intake valve is activated for full nitrogen sintering. The heating continues at a rate of 2.5-4℃ / min. When the temperature reaches 1150-1250℃, the oxygen content of the atmosphere is controlled to be 2-6wt%.

[0032] The heating rate mentioned above can be, for example, 2.5℃ / min, 3℃ / min, 3.5℃ / min or 4℃ / min.

[0033] Furthermore, the constant temperature section specifically refers to a temperature of 1250-1320℃, an atmospheric oxygen content of 2-5wt%, and a constant temperature time of 4-8h.

[0034] Further, the cooling stage specifically involves: cooling at a rate of 3-5℃ / min; holding at 1150-1210℃ for 0.5-1h with the oxygen content controlled at 0.7-1.1wt%; continuing cooling at 4-6℃ / min after reaching 1150℃, controlling the oxygen partial pressure decrease rate at 0.006-0.011wt% / min; controlling the oxygen content at 1000-1010℃ with 0.1wt%; controlling the oxygen content at 900-910℃ with 0.01wt%; and using full nitrogen protection until sintering is complete after the temperature drops below 900℃.

[0035] The aforementioned cooling rate can be, for example, 4℃ / min, 4.5℃ / min, 5℃ / min, 5.5℃ / min, or 6℃ / min.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] Fe in the main component of manganese-zinc ferrite materials 3+ Ions can increase the Curie temperature, increase the Fe2O3 content, and increase Fe 3+ The number of ions will increase, but at the same time Fe 2+The number of ions will also increase, Fe 3+ Ions and Fe 2+ Electron migration between ions leads to a decrease in resistivity; appropriate Mn 2+ Mn 3+ and Mn 4+ Zn helps improve resistivity and reduce eddy current losses, which is crucial for reducing energy loss and improving electromagnetic performance in high-frequency applications; 2+ It helps reduce eddy current loss and hysteresis loss of materials at high frequencies, but its content is negatively correlated with the Curie temperature of manganese-zinc ferrite.

[0038] Trace additives in manganese-zinc ferrite materials can significantly alter the ionic valence state, microstructure, and grain boundary composition of the materials, thereby affecting the initial permeability at room temperature, saturation magnetic flux density at room temperature, power loss at high frequencies, and even the Curie temperature. For example, trace additives such as V₂O₅, Bi₂O₃, and In₂O₃ can reduce grain boundary energy, promote uniform grain growth during sintering, improve the density and initial permeability of manganese-zinc ferrite materials, increase grain size, and thus improve the magnetic properties of the materials. CaO, SiO₂, and Nb₂ are also noteworthy additives. Trace additives such as O5 can form a high-resistivity layer at grain boundaries, reducing eddy current losses at grain boundaries, lowering power loss at high frequencies, and improving the electromagnetic stability of the material. Trace additives such as CoO, MoO, SnO2, and TiO2 can dissolve in the spinel lattice, replacing the main component ions and adjusting the saturation magnetization, Curie temperature, and temperature characteristics of the material. Since the synergistic effect of a single component is minimal, multiple components are often required in combination. However, there are often interactions and interferences between various trace additives. Different amounts and types of additives will have different effects on the performance of manganese-zinc ferrite materials.

[0039] Therefore, in the actual research and development process, the adjustment of the amount of main component raw materials and the composition and amount of trace additives will have unpredictable effects on the initial permeability, saturation magnetic flux density, high-frequency impedance performance and Curie temperature of manganese zinc ferrite materials at room temperature. The content range of the main component, the composition and amount of trace additives that the present invention claims protection for are finally determined by the inventors after a large number of creative experiments. Under the specific content range of the main component, combined with the trace additives of the specific composition and content of the present invention, the manganese zinc ferrite material can have high initial permeability (>3800), high saturation magnetic flux density (≥425mT), high impedance at high frequency (1MHz>20Ω, 25MHz>65Ω, 100MHz>110Ω) and high Curie temperature (≥145℃). Detailed Implementation

[0040] To enable those skilled in the art to more clearly understand the technical solutions described in this invention, the following embodiments are provided for illustration. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0041] Unless otherwise specified, the raw materials, reagents or apparatus used in the following examples and comparative examples are available from conventional commercial sources or can be obtained by existing known methods.

[0042] In the examples and comparative examples below, the degree of polymerization of PVA is 400-1800, and the weight-average molecular weight is approximately 23,000-30,000. Example 1

[0043] The method for preparing high-frequency, high-permeability, high-impedance manganese-zinc ferrite materials according to this embodiment includes the following steps:

[0044] Step S1: The main components, calculated as oxides, are mixed at Fe2O3 49.43mol%, MnO2 32.24mol%, with the balance being ZnO, and calcined at 910±10℃ for 2h to obtain calcined powder.

[0045] Step S2: Mix calcined powder, trace additives, water and PVA (the mass ratio of calcined powder to water is 5:3, the amount of PVA used is 0.9 wt% of calcined powder, and the trace additives, by weight of the main components, consist of the following components: CaO 200 ppm, CoO 3500 ppm, MoO 300 ppm, Bi2O3 300 ppm, Nb2O5 50 ppm) to obtain a slurry;

[0046] Step S3: The slurry is ball-milled with 1 / 4-inch steel balls until the particle size of the powder in the slurry is 1.0-2.0 μm for 3 hours. After ball milling, the slurry is spray-granulated to obtain ferrite particles.

[0047] Step S4: Compact the ferrite particles to obtain a green core with specifications of T25*15*10 (outer diameter 25mm, inner diameter 15mm, height 10mm) and a target density of 3.3±0.2g / cm³. 3 ;

[0048] Step S5: Perform staged sintering on the green blank to obtain a high permeability and high impedance manganese zinc ferrite material.

[0049] The staged sintering process includes a heating stage, a isothermal stage, and a cooling stage.

[0050] The heating stage is as follows: the temperature is increased at a rate of 3℃ / min. When the temperature reaches 870℃, the air intake valve is closed and the nitrogen intake valve is started for full nitrogen sintering. The temperature continues to increase at a rate of 3℃ / min. When the temperature reaches 1210℃, the oxygen content of the atmosphere is controlled at 3wt%, and the process is ready to enter the constant temperature stage.

[0051] The constant temperature section is specifically designed as follows: the temperature is controlled at 1290℃, the oxygen content in the atmosphere is 3wt%, and the constant temperature time is 7h.

[0052] The cooling process is as follows: Cooling is carried out at a rate of 3℃ / min. When the temperature drops to 1190℃, it is held for 0.5 hours, with the oxygen content of the atmosphere controlled at 1.0wt%. When the temperature drops to 1150℃, cooling continues at a rate of 3℃ / min, with the oxygen partial pressure decreasing at a rate of 0.008wt% / min. When the temperature drops to 1000℃, the oxygen content of the atmosphere is controlled at 0.1wt%. When the temperature drops to 900℃, the oxygen content of the atmosphere is controlled at 0.01wt%. When the temperature drops below 900℃, full nitrogen protection is used until the sintering is completed. Example 2

[0053] The high-permeability, high-impedance manganese-zinc ferrite material of this embodiment differs from that of Embodiment 1 only in that the main components are mixed as oxides, with Fe2O3 48.79 mol%, MnO2 32.49 mol%, and the balance being ZnO; all other conditions are the same as in Embodiment 1. Example 3

[0054] The high-permeability, high-impedance manganese-zinc ferrite material of this embodiment differs from that of Example 1 only in that the main components are mixed as oxides, with Fe2O3 50.25 mol%, MnO2 31.89 mol%, and the balance being ZnO; all other conditions are the same as in Example 1.

[0055] Comparative Example 1

[0056] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 1 only in that the main components, calculated as oxides, are mixed at 52.15 mol% Fe2O3, 30.76 mol% MnO2, with the balance being ZnO; all other conditions are the same as in Example 1.

[0057] Comparative Example 2

[0058] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 1 only in that the main components, calculated as oxides, are mixed at 47.76 mol% Fe2O3, 33.42 mol% MnO2, with the balance being ZnO; all other conditions are the same as in Example 1.

[0059] Comparative Example 3

[0060] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the CoO content in the trace additive is adjusted to 4500 ppm; all other conditions are the same as in Example 2.

[0061] Comparative Example 4

[0062] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the CoO content in the trace additive is adjusted to 1700 ppm; all other conditions are the same as in Example 2.

[0063] Comparative Example 5

[0064] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the Bi2O3 in the trace additive is adjusted to 600 ppm; all other conditions are the same as in Example 2.

[0065] Comparative Example 6

[0066] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the Bi2O3 in the trace additive is adjusted to 200 ppm; all other conditions are the same as in Example 2.

[0067] Comparative Example 7

[0068] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high-frequency applications differs from Example 2 only in that the CaO content in the trace additive is adjusted to 800 ppm; all other conditions are the same as in Example 2.

[0069] Comparative Example 8

[0070] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the CaO content in the trace additive is adjusted to 100 ppm; all other conditions are the same as in Example 2.

[0071] Comparative Example 9

[0072] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high-frequency applications differs from Example 2 only in that the Nb2O5 in the trace additive is adjusted to 0 ppm; all other conditions are the same as in Example 2.

[0073] Comparative Example 10

[0074] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the trace additives are adjusted: Nb2O5 is replaced with 1000 ppm NiO; all other conditions are the same as in Example 2.

[0075] Comparative Example 11

[0076] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the trace additives are adjusted: CoO is replaced with 15 ppm SiO2; all other conditions are the same as in Example 2.

[0077] Comparative Example Twelve

[0078] The comparative example of a high-permeability, high-impedance manganese-zinc ferrite material for high frequency differs from Example 2 only in that the trace additives are adjusted: Bi2O3 is replaced with 500 ppm SnO2; all other conditions are the same as in Example 2.

[0079] Performance testing: The high permeability and high impedance manganese zinc ferrite materials of the above embodiments and comparative examples were tested using an Agilent 4294A precision impedance analyzer. The initial permeability ui value was tested using 10 turns of 0.25 mm wire; the impedance and Curie temperature (Tc) were tested using 1 turn of 0.55 mm wire. The results are shown in Table 1 below.

[0080] Table 1 Test Results

[0081]

[0082] Results analysis:

[0083] The manganese-zinc ferrite materials provided in Embodiments 1-3 of this invention possess high initial permeability, high saturation magnetic flux density, high impedance at high frequencies, and high Curie temperature.

[0084] As can be seen from Comparative Examples 1 and 2, when the molar percentages of Fe2O3, MnO2 and ZnO in the main components are not within the scope of protection claimed in this invention, although the Curie temperature and saturation magnetic flux density may increase, the initial permeability decreases and the high-frequency impedance characteristics deteriorate.

[0085] As can be seen from Comparative Examples 3 and 4, when the amount of CoO added in the trace additive or the mass ratio of CoO, Bi2O3 and CaO is not within the scope of protection claimed in this invention, although the Curie temperature and saturation magnetic flux density do not change much, the initial permeability decreases significantly and the high-frequency impedance deteriorates.

[0086] As can be seen from Comparative Examples 5 and 6, when the amount of Bi2O3 added in the trace additive or the mass ratio of CoO, Bi2O3 and CaO is not within the scope of protection claimed in this invention, the initial permeability decreases significantly, the high-frequency impedance deteriorates, and the saturation magnetic flux density decreases.

[0087] As can be seen from Comparative Examples 7 and 8, when the amount of Bi2O3 added in the trace additive or the mass ratio of CoO, Bi2O3 and CaO is not within the scope of protection claimed in this invention, the initial permeability decreases slightly, the high-frequency impedance deteriorates, and the saturation magnetic flux density decreases.

[0088] As can be seen from Comparative Example 9, when the amount of Nb2O5 added in the trace additive is 0, although the initial magnetic permeability is slightly improved and the saturation magnetic flux density does not change much, the high-frequency impedance deteriorates.

[0089] As can be seen from Comparative Example 10, replacing Nb2O5 with NiO significantly reduces the initial permeability, worsens the high-frequency impedance, and slightly reduces the saturation magnetic flux density.

[0090] As can be seen from Comparative Example 11, replacing CoO with SiO2 significantly reduces the initial permeability, worsens the high-frequency impedance, and slightly reduces the saturation magnetic flux density.

[0091] As can be seen from Comparative Example 12, replacing Bi2O3 with SnO2 slightly decreases the initial permeability, worsens the high-frequency impedance, and slightly decreases the saturation magnetic flux density.

[0092] In summary, by using a specific amount of main component and a specific amount of trace additives under a specific sintering process, this invention yields a manganese-zinc ferrite material that possesses high initial permeability, high impedance at high frequencies, high Curie temperature, and high saturation magnetic flux density.

[0093] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A high-permeability, high-impedance manganese-zinc ferrite material for high-frequency applications, characterized in that, It consists of a main component and trace additives: the main component, calculated as oxides, consists of Fe2O3 50.0-51.0 mol%, MnO2 31.0-32.0 mol%, with the balance being ZnO; the trace additives, calculated by weight of the main component, consist of the following components: CaO 200-700 ppm, CoO 2000-4000 ppm, MoO 200-400 ppm, Bi2O3 300-500 ppm, Nb2O5 20-100 ppm; In the trace additive, the mass ratio of CoO, Bi2O3 and CaO is 15-20:1-2:1; The method for preparing high-permeability, high-impedance manganese-zinc ferrite material for high frequency includes the following steps: Step S1: Mix the main components according to the ratio, calcine, and obtain calcined powder; Step S2: Mix the calcined powder, trace additives, water and PVA to obtain a slurry; Step S3: The slurry is ball-milled, and after ball milling, the slurry is spray-granulated to obtain ferrite particles; Step S4: Compact the ferrite particles to obtain a green embryo; Step S5: Perform staged sintering on the green blank to obtain a high permeability and high impedance manganese zinc ferrite material; The staged sintering described in step S5 includes a heating section, a isothermal section, and a cooling section; The specific heating stage is as follows: The temperature is increased at a rate of 2.5-4℃ / min. When the temperature reaches 800-900℃, the air intake valve is closed, and the nitrogen intake valve is activated for full nitrogen sintering. The temperature continues to increase at a rate of 2.5-4℃ / min. When the temperature reaches 1150-1250℃, the oxygen content of the atmosphere is controlled at 2-6 wt%. The constant temperature section is specifically defined as follows: the temperature is controlled at 1250-1320℃, the oxygen content in the atmosphere is 2-5wt%, and the constant temperature time is 4-8h; The cooling stage specifically involves the following steps: Cooling is performed at a rate of 3-5℃ / min. When the temperature drops to 1150-1210℃, the temperature is held for 0.5-1h, with the oxygen content of the atmosphere controlled at 0.7-1.1wt%. After the temperature drops to 1150℃, cooling continues at a rate of 4-6℃ / min, with the oxygen partial pressure decreasing at a rate of 0.006-0.011wt% / min. When the temperature drops to 1000-1010℃, the oxygen content of the atmosphere is controlled at 0.1wt%. When the temperature drops to 900-910℃, the oxygen content of the atmosphere is controlled at 0.01wt%. When the temperature drops below 900℃, full nitrogen protection is used until the sintering is completed.

2. The high permeability high impedance Mn-Zn ferrite material for high frequency according to claim 1, characterized by, The high-permeability, high-impedance manganese-zinc ferrite material used for high-frequency applications consists of a main component and trace additives. Composition: The main components, calculated as oxides, consist of 50.0-51.0 mol% Fe2O3, 31.0-32.0 mol% MnO2, with the balance being ZnO; the trace additives, calculated by weight of the main components, consist of the following components: 200 ppm CaO, 3500 ppm CoO, 300 ppm MoO, 300 ppm Bi2O3, and 50 ppm Nb2O5.

3. The production method of high permeability high impedance Mn-Zn ferrite material for high frequency according to any one of claims 1 to 2, characterized by, Includes the following steps: Step S1: Mix the main components according to the ratio, calcine, and obtain calcined powder; Step S2: Mix the calcined powder, trace additives, water and PVA to obtain a slurry; Step S3: The slurry is ball-milled, and after ball milling, the slurry is spray-granulated to obtain ferrite particles; Step S4: Compact the ferrite particles to obtain a green embryo; Step S5: Perform staged sintering on the green blank to obtain a high permeability and high impedance manganese zinc ferrite material; The staged sintering described in step S5 includes a heating section, a isothermal section, and a cooling section; The specific heating stage is as follows: The temperature is increased at a rate of 2.5-4℃ / min. When the temperature reaches 800-900℃, the air intake valve is closed, and the nitrogen intake valve is activated for full nitrogen sintering. The temperature continues to increase at a rate of 2.5-4℃ / min. When the temperature reaches 1150-1250℃, the oxygen content of the atmosphere is controlled at 2-6 wt%. The constant temperature section is specifically defined as follows: the temperature is controlled at 1250-1320℃, the oxygen content in the atmosphere is 2-5wt%, and the constant temperature time is 4-8h; The cooling stage specifically involves the following steps: Cooling is performed at a rate of 3-5℃ / min. When the temperature drops to 1150-1210℃, the temperature is held for 0.5-1h, with the oxygen content of the atmosphere controlled at 0.7-1.1wt%. After the temperature drops to 1150℃, cooling continues at a rate of 4-6℃ / min, with the oxygen partial pressure decreasing at a rate of 0.006-0.011wt% / min. When the temperature drops to 1000-1010℃, the oxygen content of the atmosphere is controlled at 0.1wt%. When the temperature drops to 900-910℃, the oxygen content of the atmosphere is controlled at 0.01wt%. When the temperature drops below 900℃, full nitrogen protection is used until the sintering is completed.

4. The method of producing high permeability high impedance Mn-Zn ferrite material for high frequency according to claim 3, characterized by, The calcination temperature in step S1 is 900-1000℃; the calcination time is 1-6h.

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