A kind of ultra-high magnetic saturation manganese-zinc ferrite core material and preparation method thereof

Abstract

The invention relates to the technical field of oxide magnetic material manufacturing, and in particular to an ultra-high magnetic saturation manganese-zinc ferrite core material and a preparation method thereof, wherein the ultra-high magnetic saturation manganese-zinc ferrite core material is characterized in that it comprises a main material and an additive, wherein the mass ratio of the main material to the additive is (8-10):1, the main material comprises ferric oxide, manganese oxide and zinc oxide, and the corresponding molar ratio is (4.8-5.2):(1.7-2.1):1; when the ultra-high magnetic saturation manganese-zinc ferrite core material is sintered, a temperature holding platform of 2-3h is designed at 900-920°C in both the heating stage and the cooling stage. The ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention has an initial magnetic permeability of 1400μi; a maximum core loss of 800mW (25℃100KHz 200mT); and a magnetic induction intensity (Bs) that can reach the theoretical limit of 600mT (25℃10kHz 1200A / m), thereby achieving a breakthrough in the industrial application of manganese-zinc ferrite.

Description

Technical Field

[0001] The invention relates to the technical field of oxide magnetic material manufacturing, and in particular to an ultra-high magnetic saturation manganese-zinc ferrite core material and a preparation method thereof. Background Art

[0002] With the development of communication technology and digitalization of electronic products, electronic equipment manufacturing technology is constantly being updated and improved. The magnetic core component market has an increasing demand for ultra-low loss power ferrite materials and high permeability ferrite materials for electromagnetic compatibility of modern network communication systems and digital electronic equipment.

[0003] Especially in recent years, the development of autonomous driving and new energy vehicles has put forward new requirements for soft magnetic ferrites and components. High-performance cores with large current DC load capacity are widely used in power supply devices such as new energy vehicles and charging piles, and have been widely used in common mode inductors, PFC, DC-DC, DC-AC inverter and other fields, replacing the iron-nickel field of soft magnetic alloys and expanding the application field of manganese-zinc. The reason for the replacement is that on the one hand, the loss of manganese-zinc ferrite core materials is 30% of that in the iron-nickel field, while the material cost is about 40% of that in the iron-nickel field. On the other hand, because manganese-zinc ferrite itself is also a very stable oxide, there is no oxidation problem in manganese-zinc ferrite core materials. Therefore, manganese-zinc ferrite core materials have both the low cost, high stability and high reliability requirements of automotive products.

[0004] Magnetic saturation capacity Bs refers to the influence of an external magnetic field on the magnetic core. At a fixed frequency, the magnetic core can withstand the maximum external magnetic field. When the external magnetic field is greater than the core's tolerable limit Bs, the initial magnetic permeability will collapse to zero. Therefore, magnetic saturation capacity represents the magnetic stability of the core material.

[0005] However, although the manganese-zinc ferrite in the prior art has a certain magnetic saturation capacity, it has been difficult to achieve a breakthrough in making the magnetic saturation capacity reach the theoretical value Bs 600.

[0006] In view of this, the present invention is proposed. Summary of the invention

[0007] The first object of the present invention is to provide an ultra-high magnetic saturation manganese-zinc ferrite core material, the magnetic induction intensity (Bs) of the core material can reach the theoretical limit of 600mT (25°C; 10kHz; 1200A / m), so that the industrial application of manganese-zinc ferrite has achieved a breakthrough progress;

[0008] The second object of the present invention is to provide a method for preparing an ultra-high magnetic saturation manganese-zinc ferrite core material. The sintering method adopted not only does not reduce the density of the core material, but on the contrary increases the density of the core material itself by 3%.

[0009] The present invention provides an ultra-high magnetic saturation manganese-zinc ferrite core material, comprising a main material and an additive, wherein the mass ratio of the main material to the additive is (8-10): 1,

[0010] The main ingredients include ferric oxide, manganese oxide and zinc oxide, and the corresponding molar ratio is (4.8-5.2): (1.7-2.1): 1;

[0011] When the ultra-high magnetic saturation manganese-zinc ferrite core material is sintered, a temperature holding platform of 2-3 hours is designed at 900-920° C. in both the heating stage and the cooling stage.

[0012] The molar ratio of ferric oxide, manganese oxide and zinc oxide in the main material of the ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention is (4.8-5.2): (1.7-2.1): 1. At the same time, during the sintering process, a 2-3h temperature holding platform is designed at 900-920°C in both the heating stage and the cooling stage. Under the specific main material composition and proportion, the temperature holding platform in the heating stage can cause part of Mn2O3 to be converted into Mn3O4, while releasing oxygen, so that micropores are generated on the surface and inside of the core material. At the same time, the core material will shrink tightly at this temperature to make the material more compact; and in the cooling stage, this temperature holding platform can convert the remaining Mn2O3 into Mn3O4, thereby optimizing the density and avoiding the conversion of trivalent iron into divalent iron. Therefore, the magnetic induction intensity (Bs) of the manganese-zinc ferrite prepared by the sintering method of the present invention can reach the theoretical limit of 600mT (25°C, 10kHz, 1200A / m), and its magnetic properties have achieved a breakthrough development.

[0013] In addition, the preparation process of the manganese-zinc ferrite core material of the present invention also includes additives, and the present invention does not specifically limit the composition of the additives. Specifically, the additives include nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide, and the corresponding molar ratios are (6-8): (3-4): 1: (0.5-0.8): (0.1-0.15).

[0014] As a preferred embodiment of the present technical solution, the mass ratio of the main material to the additive is 9:1.

[0015] The present invention also discloses a method for preparing the ultra-high magnetic saturation manganese-zinc ferrite core material, which specifically comprises the following steps:

[0016] S1, grinding the main material and the additive respectively to obtain the ground main material and the additive;

[0017] S2, premixing the ground main material and additives in an atmosphere of 80% nitrogen + 20% air, and spray granulating after premixing to obtain granular material;

[0018] S3. The granular material is pressed and sintered to obtain an ultra-high magnetic saturation manganese-zinc ferrite core material.

[0019] As a preferred embodiment of the present technical solution, in step S3, during the sintering, the sintering procedure is controlled as follows:

[0020] First, the temperature is raised from room temperature to 900-920°C at a heating rate of 3-5°C / min, and kept at 900-920°C for 2-3h;

[0021] Then, the temperature is raised from 900-920°C to 1300-1400°C at a heating rate of 3-5°C / min, and kept at 1300-1400°C for 3-5h;

[0022] Then, the temperature is lowered from 1300-1400℃ to 900-920℃ by natural cooling, and kept at 900-920℃ for 2-3h;

[0023] Finally, the temperature is cooled down from 900-920℃ to room temperature through natural cooling.

[0024] The preparation method of the ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention comprises the steps of grinding, premixing, spray granulation and sintering, wherein the specific parameters and processes of grinding, premixing and spray granulation are not specifically limited, and can be adaptively adjusted according to the properties of the main materials and additives, or the methods in the prior art can be adopted. During the sintering process, the following sintering procedure is mainly adopted. A 2-3h temperature holding platform is designed at 900-920℃ in the heating stage and the cooling stage, and a maximum temperature holding platform is set at 1300-1400 degrees Celsius. The temperature holding platform in the heating stage can cause part of the Mn2O3 to be converted into Mn3O4, and release oxygen at the same time, so that micropores are generated on the surface and inside of the magnetic core material. At the same time, the magnetic core material will shrink tightly at this temperature to make the material more compact; in the cooling stage, this temperature holding platform can convert the remaining Mn2O3 into Mn3O4, thereby optimizing the density and avoiding the conversion of trivalent iron into divalent iron; and the setting of the maximum temperature holding platform is directly related to the growth of magnetic chips. When the temperature is held for too long, the magnetic chips are too large and the magnetic core is easy to break. If the temperature is held for too short, it is not conducive to the growth of the magnetic chips and may lead to a decrease in the initial magnetic permeability. Therefore, in the present invention, no matter how big the magnetic core is, the time of the maximum temperature holding platform is set to 3-5h. In summary, under the special sintering procedure of the present invention, the actual core density does not decrease due to the generation of pores during the sintering process. Instead, the density of the core material itself is increased by 3%. The increase in the core density can significantly increase the saturation magnetic induction intensity Bs of the core material.

[0025] As a preferred embodiment of the present technical solution, in step S3, during the sintering, the sintering procedure is controlled as follows:

[0026] First, the temperature is raised from room temperature to 910°C at a heating rate of 3-5°C / min, and kept at 910°C for 2-3h;

[0027] Then, the temperature is raised from 910°C to 1300-1400°C at a heating rate of 3-5°C / min, and kept at 1300-1400°C for 3-5h;

[0028] Then, the temperature is lowered from 1300-1400℃ to 910℃ by natural cooling, and kept at 910℃ for 2-3h;

[0029] Finally, the temperature is lowered from 910°C to room temperature through natural cooling.

[0030] Research shows that when a temperature holding platform of 2-3h is designed at 910℃ in both the heating stage and the cooling stage, the magnetic saturation capacity of the prepared ferrite core material can reach the ideal simulation value Bs 600. At the same time, due to the addition of additives such as nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide, the lattice parameters of the ferrite can be further adjusted, which is conducive to the reduction of the grain size and porosity of the manganese-zinc ferrite, and the density of the material is increased, thereby improving the magnetic properties of the ferrite, and giving the manganese-zinc ferrite core material a high magnetic flux rate at high frequency and ultra-high frequency. Therefore, the magnetic induction intensity (Bs) of the manganese-zinc ferrite prepared by the sintering method of the present invention can reach the theoretical limit of 600mT (25℃10kHz1200A / m), and its magnetic properties have achieved a breakthrough development, which provides the possibility for manganese-zinc ferrite to replace the soft magnetic alloy market across fields, and at the same time can reduce the cost of the vehicle-mounted PFC market by 70%.

[0031] On the basis of the above technical scheme, the present invention does not specifically limit the grinding method of the main material and the additive, and ball milling or other mechanical grinding methods can be selected, and the specific grinding time can be adjusted according to actual needs. Specifically, in step S1, the main material and the additive are both ground by ball milling for 1-3 hours.

[0032] As a preferred embodiment of the present technical solution, in step S2, during the premixing, the temperature is controlled to be 350-450° C. in an atmosphere of 80% nitrogen + 20% air to ensure the premixing effect of the main material and the additive.

[0033] As a preferred embodiment of the present technical solution, in step S3, the sintering is carried out in a vacuum furnace.

[0034] The ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention has at least the following technical effects:

[0035] 1. The ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention has ultra-high magnetic saturation capability through the special composition and ratio of the main materials and additives, and the special sintering method when making the magnetic core. The magnetic induction intensity (Bs) can reach the theoretical limit of 600mT (25℃10kHz1200A / m). Its magnetic properties have achieved a breakthrough development, which provides the possibility for manganese-zinc ferrite to replace the soft magnetic alloy market across fields, and at the same time can reduce the cost of the vehicle-mounted PFC market by 70%;

[0036] 2. The addition of additives such as nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide in the present invention can further adjust the lattice parameters of ferrite, which is beneficial to the reduction of grain size and porosity of manganese-zinc ferrite, improve the density of the material, and thus improve the magnetic properties of ferrite, give the manganese-zinc ferrite core material high magnetic flux at high frequency and ultra-high frequency, and improve the magnetic properties of manganese-zinc ferrite;

[0037] 3. When the ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention is sintered, a 2-3h temperature holding platform is designed at 900-920°C in both the heating stage and the cooling stage. The temperature holding platform in the heating stage can cause part of Mn2O3 to be converted into Mn3O4, while releasing oxygen, so that micropores are generated on the surface and inside of the core material. At the same time, the core material will shrink tightly at this temperature to make the material more compact; and in the cooling stage, this temperature holding platform can convert the remaining Mn2O3 into Mn3O4, thereby optimizing the density and avoiding the conversion of trivalent iron into divalent iron. In the sintering process, the actual core density does not decrease due to the generation of pores, but instead increases the density of the core material itself by 3%, and the increase in the core density can significantly increase the saturation magnetic induction intensity Bs of the core material. Therefore, the sintering method of the present invention can effectively control the density, grain size, porosity and distribution of ferrite materials inside and between grains, thereby increasing the saturation magnetic induction intensity Bs of the magnetic core material;

[0038] 4. The ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention has an initial magnetic permeability of 1400μi; a maximum core loss of 800mW (25℃100KHz 200mT); and a magnetic induction intensity (Bs) that can reach the theoretical limit of 600mT (25℃10kHz 1200A / m), thereby achieving a breakthrough in the industrial application of manganese-zinc ferrite. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 The saturation magnetic induction intensity of the manganese-zinc ferrite prepared in Example 1 of the present invention;

[0041] Figure 2 The saturation magnetic flux density of the conventional manganese-zinc ferrite prepared in the comparative example of the present invention;

[0042] Figure 3 This is a comparison chart of the current resistance of the present invention (wherein X28A is the manganese-zinc ferrite obtained in Example 1);

[0043] Figure 4 The power loss curve of the manganese-zinc ferrite prepared in Example 1 of the present invention at room temperature varies with the peak magnetic flux density;

[0044] Figure 5 The power loss of the manganese-zinc ferrite prepared in Example 1 of the present invention varies with temperature;

[0045] Figure 6 The graph shows the change of magnetic permeability of the manganese-zinc ferrite obtained in Example 1 of the present invention with temperature. DETAILED DESCRIPTION

[0046] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0047] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this description, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0048] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] Example 1

[0050] Raw material composition of manganese-zinc ferrite core material

[0051] The molar ratio of ferric oxide, manganese oxide and zinc oxide in the main material is 5:2:1;

[0052] The molar ratio of nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide in the additive is 7:3.5:1:0.6:0.12;

[0053] The mass ratio of main material to additive is 9:1.

[0054] The method for preparing a manganese-zinc ferrite core material comprises the following steps:

[0055] S11, ball-milling the main material and the additives respectively to obtain the ground main material and the additives;

[0056] S12, premixing the ground main material and additives at 400° C. in an atmosphere of 80% nitrogen + 20% air, and spray granulating the premixed material to obtain a granular material;

[0057] S13, the pellets are pressed and sintered, and the sintering procedure is as follows:

[0058] First, the temperature was raised from room temperature to 910°C at a heating rate of 4°C / min and kept at 910°C for 2.5 h;

[0059] Then, the temperature was increased from 910°C to 1350°C at a heating rate of 4°C / min and kept at 1350°C for 3 h;

[0060] Then, the temperature was lowered from 1350°C to 910°C by natural cooling, and kept at 910°C for 2.5 hours;

[0061] Finally, the temperature was lowered from 910°C to room temperature by natural cooling to obtain an ultra-high magnetic saturation manganese-zinc ferrite core material.

[0062] Example 2

[0063] Raw material composition of manganese-zinc ferrite core material

[0064] The molar ratio of ferric oxide, manganese oxide and zinc oxide in the main material is 4.8:1.7:1;

[0065] The molar ratio of nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide in the additive is 6:3:1:0.8:0.1;

[0066] The mass ratio of main material to additive is 9:1.

[0067] The method for preparing a manganese-zinc ferrite core material comprises the following steps:

[0068] S21, ball-milling the main material and the additives respectively to obtain the ground main material and the additives;

[0069] S22, premixing the ground main material and additives at 400° C. in an atmosphere of 80% nitrogen + 20% air, and spray granulating the premixed material to obtain a granular material;

[0070] S23, the pellets are pressed and sintered, and the sintering procedure is as follows:

[0071] First, the temperature was raised from room temperature to 920°C at a heating rate of 3°C / min and kept at 920°C for 2.5 h;

[0072] Then, the temperature was increased from 920°C to 1400°C at a heating rate of 3°C / min and kept at 1400°C for 3 h;

[0073] Then, the temperature was lowered from 1400°C to 920°C by natural cooling, and kept at 920°C for 3 hours;

[0074] Finally, the temperature was lowered from 920°C to room temperature by natural cooling to obtain an ultra-high magnetic saturation manganese-zinc ferrite core material.

[0075] Example 3

[0076] Raw material composition of manganese-zinc ferrite core material

[0077] The molar ratio of ferric oxide, manganese oxide and zinc oxide in the main material is 5.2:2.1:1;

[0078] The molar ratio of nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide in the additive is 8:4:1:0.5:0.15;

[0079] The mass ratio of main material to additive is 9:1.

[0080] The method for preparing a manganese-zinc ferrite core material comprises the following steps:

[0081] S31, ball-milling the main material and the additives respectively to obtain the ground main material and the additives;

[0082] S32, premixing the ground main material and additives at 400° C. in an atmosphere of 80% nitrogen + 20% air, and spray granulating the premixed material to obtain a granular material;

[0083] S33, the pellets are pressed and sintered, and the sintering procedure is as follows:

[0084] First, the temperature was raised from room temperature to 900°C at a heating rate of 5°C / min and kept at 900°C for 3 h;

[0085] Then, the temperature was increased from 900°C to 1300°C at a heating rate of 5°C / min and kept at 1300°C for 5 h;

[0086] Then, the temperature was lowered from 1300°C to 900°C by natural cooling, and kept at 900°C for 3 hours;

[0087] Finally, the temperature was naturally cooled from 900°C to room temperature to obtain an ultra-high magnetic saturation manganese-zinc ferrite core material.

[0088] Comparative example (conventional manganese-zinc ferrite)

[0089] The raw material composition and pre-sintering treatment of the manganese-zinc ferrite core material are the same as those in Example 1, and the sintering procedure is as follows:

[0090] During sintering, the temperature is first increased from 600°C to 1000°C at a heating rate of 4°C per minute, and then continued to be increased at 4°C per minute to the highest temperature holding platform. The highest temperature holding platform is set to 1350°C, and the holding time is set to 3h. After the highest temperature holding period, it is cooled to room temperature by natural cooling to obtain a traditional manganese-zinc ferrite core material.

[0091] In order to characterize the saturation magnetic flux density of the manganese-zinc ferrite obtained by the special sintering method of the present invention, the saturation magnetic flux density of the manganese-zinc ferrite obtained in the embodiment and the comparative example was tested. The test results are as follows: Figure 1-2 shown.

[0092] contrast Figure 1-2 It can be seen that the saturation magnetic induction intensity of traditional manganese-zinc ferrite is lower than 500mT at room temperature of 25°C. The saturation magnetic induction intensity (Bs) of the manganese-zinc ferrite obtained by sintering in Example 1 of the present invention can reach the theoretical limit of 600mT, which is significantly improved compared with the manganese-zinc ferrite obtained by the traditional sintering method, making a breakthrough in the industrial application of manganese-zinc ferrite.

[0093] The current resistance can more intuitively characterize the magnitude of the saturation magnetic induction intensity of the manganese-zinc ferrite. Therefore, the current resistance of the manganese-zinc ferrite X28A sintered in Example 1 and the conventional manganese-zinc ferrite obtained in the control example was tested. The test results are as follows: Figure 3 shown.

[0094] Depend on Figure 3It can be seen that the magnetic saturation capacity of traditional manganese-zinc ferrite drops sharply when the current exceeds 300mA in the range of 25-120°C. Compared with the manganese-zinc ferrite obtained by the traditional sintering method, the magnetic saturation capacity of X28A of the present invention is relatively stable in the range of 25-120°C and has excellent current resistance.

[0095] In addition, the present invention also tests the power loss of the manganese-zinc ferrite obtained by sintering Example 1. The test results are as follows: Figure 4-6 shown.

[0096] Combination Figure 4-6 It can be concluded that the initial magnetic permeability of the sintered manganese-zinc ferrite is 1400μi, and the maximum core loss is 800kW / m at 25°C, 100KHz, and 200mTBs. 3 .

[0097] In summary, the ultra-high magnetic saturation manganese-zinc ferrite core material of the present invention has an initial magnetic permeability of 1400μi; a maximum core loss of 800mW (25℃100KHz 200mT); and a magnetic induction intensity (Bs) that can reach the theoretical limit of 600mT (25℃10kHz 1200A / m). Therefore, the magnetic induction intensity (Bs) of the manganese-zinc ferrite prepared by the sintering method of the present invention can reach the theoretical limit of 600mT (25℃10kHz 1200A / m), and its magnetic properties have achieved a breakthrough development, which provides the possibility for manganese-zinc ferrite to replace the soft magnetic alloy market across fields, and at the same time can reduce the cost of the vehicle-mounted PFC market by 70%.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements 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. An ultra-high magnetic saturation manganese-zinc ferrite core material, characterized in that: It comprises a main material and an additive, wherein the mass ratio of the main material to the additive is (8-10):1, The main ingredients include ferric oxide, manganese oxide and zinc oxide, and the corresponding molar ratio is (4.8-5.2): (1.7-2.1): 1; When the ultra-high magnetic saturation manganese-zinc ferrite core material is sintered, a 2-3h temperature holding platform is designed at 900-920°C in both the heating stage and the cooling stage; The additives include nickel oxide, silicon oxide, calcium oxide, niobium oxide and molybdenum oxide, and the corresponding molar ratios are (6-8): (3-4): 1: (0.5-0.8): (0.1-0.15); The method for preparing the ultra-high magnetic saturation manganese-zinc ferrite core material comprises the following steps: S1, grinding the main material and the additives respectively to obtain the ground main material and the additives; S2, premixing the ground main material and additives in an atmosphere of 80% nitrogen + 20% air, and spray granulating after premixing to obtain granular material; S3, the granular material is pressed and sintered to obtain an ultra-high magnetic saturation manganese-zinc ferrite core material; In step S3, during the sintering, the sintering procedure is controlled as follows: First, the temperature is raised from room temperature to 900-920°C at a heating rate of 3-5°C / min, and kept at 900-920°C for 2-3h; Then, the temperature is raised from 900-920°C to 1300-1400°C at a heating rate of 3-5°C / min, and kept at 1300-1400°C for 3-5h; Then, the temperature is lowered from 1300-1400℃ to 900-920℃ by natural cooling, and kept at 900-920℃ for 2-3h; Finally, the temperature is cooled down from 900-920℃ to room temperature through natural cooling.

2. The ultra-high magnetic saturation manganese-zinc ferrite core material according to claim 1, characterized in that: The mass ratio of the main material to the additive is 9:

1.

3. The ultra-high magnetic saturation manganese-zinc ferrite core material according to claim 1, characterized in that: In step S3, during the sintering, the sintering procedure is controlled as follows: First, the temperature is raised from room temperature to 910°C at a heating rate of 3-5°C / min, and kept at 910°C for 2-3h; Then, the temperature is raised from 910°C to 1300-1400°C at a heating rate of 3-5°C / min, and kept at 1300-1400°C for 3-5h; Then, the temperature is lowered from 1300-1400℃ to 910℃ by natural cooling, and kept at 910℃ for 2-3h; Finally, the temperature is lowered from 910°C to room temperature through natural cooling.

4. The ultra-high magnetic saturation manganese-zinc ferrite core material according to claim 1, characterized in that: In step S1, the main material and the additive are ground by ball milling for 1-3 hours.

5. The ultra-high magnetic saturation manganese-zinc ferrite core material according to claim 1, characterized in that: In step S2, during the premixing, the temperature is controlled to be 350-450°C.

6. The ultra-high magnetic saturation manganese-zinc ferrite core material according to claim 1, characterized in that: In step S3, the sintering is performed in a vacuum furnace.

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