Preparation method of manganese zinc ferrite material

Abstract

The invention relates to a preparation method of a manganese-zinc ferrite material, which comprises the following steps: prefabricating a finished product material: respectively granulating according to different formulas with the numbers of A1 to An to prepare the manganese-zinc ferrite finished product material with the numbers of A1 to An, n being an integer greater than or equal to 2; wherein the manganese zinc ferrite material prepared by each formula corresponds to different electromagnetic properties; selecting more than two manganese zinc ferrite finished product materials with the serial numbers of A1 to An, and fully mixing according to a specified mass ratio to prepare a blended material; pressing the co-mixture into a green body, and then sintering and molding to prepare the manganese zinc ferrite material; wherein the electromagnetic property of the manganese-zinc ferrite material prepared from the blending material is different from the electromagnetic property corresponding to the manganese-zinc ferrite material prepared from each manganese-zinc ferrite finished product material contained in the blending material. The method has the beneficial effects that the research and development and preparation efficiency of the ferrite material is improved, the cost is saved, and the method has wide popularization value.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic material preparation, and particularly to a preparation method of manganese-zinc ferrite materials. Background Art

[0002] Manganese-zinc soft magnetic ferrites are a type of magnetic materials with characteristics such as high magnetic permeability, high saturation magnetic flux density, and low loss, and are widely used in electronic devices such as inductors, transformers, chokes, suppressors, and filters. With the rapid development of electronic technology, these devices are facing new challenges such as high frequency, wide bandwidth, high definition, and surface mount technology. Therefore, higher requirements are put forward for soft magnetic ferrites, such as high frequency and low power consumption, high magnetic permeability and wide bandwidth, double-high (high initial magnetic permeability μi and high saturation magnetic flux density Bs) materials, as well as materials with low sintering temperature and low thermal resistance. These requirements have promoted the development of soft magnetic ferrite materials towards more efficient performance to adapt to the changing application environment.

[0003] Manganese-zinc ferrite materials are mainly produced by dry processes, which mainly involve multiple steps such as mixing (including primary ball milling, pre-sintering, doping, and secondary ball milling), forming, sintering, and grinding. More specifically, the main formula usually consists of three components, Fe 2 O 3 , MnO, and ZnO, and the performance of ferrite cores prepared with different or different ratios of the main components is significantly different. After the main component powder is dried by primary ball milling, it needs to be further pre-sintered and complete part of the solid-phase reaction to become a pre-sintered material with a certain hardness. There are a rich variety (more than a hundred kinds) of auxiliary agents available for secondary doping of the pre-sintered material, and the doping amount is usually from a few ten-thousandths to a few percent. The influence of the doping amounts of different auxiliary agents in the auxiliary agent formula on the performance of the ferrite is also extremely significant. After secondary doping of the pre-sintered material, it is subjected to secondary ball milling, drying, and then granulated to obtain a granular finished material, and then the subsequent forming and sintering steps are carried out. The sintering of the finished material further adjusts some performance parameters of the ferrite by controlling parameters such as the sintering atmosphere, sintering time, and cooling atmosphere, and finally prepares the ferrite material.

[0004] From the above process steps, it can be seen that after granulation, the composition of a main formula and an auxiliary agent formula is relatively fixed, and it is impossible to adjust the components therein by simple process means. Therefore, in the research and development of optimizing numerous electromagnetic performance parameters of ferrite materials, it is necessary to start from the main formula of raw materials and auxiliary agents, and carry out a complex, long, and extremely costly research and development and preparation process.

[0005] In addition, due to the differences in the formulations of different ferrite materials, the mixing step in actual production is prone to powder contamination, so independent equipment or frequent cleaning is required, which undoubtedly increases the production cost of ferrite materials and reduces production efficiency. Alternatively, the adjusted ferrite material formula or the corresponding sintering process is not good, resulting in the electromagnetic properties of the ferrite material not meeting the conditions of use, and also causing waste of resources. These challenges limit the research and development and preparation efficiency of manganese-zinc ferrite materials. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for preparing a manganese-zinc ferrite material, which solves the technical problems of low efficiency and high cost in the research and development and preparation of the existing manganese-zinc ferrite.

[0008] (II) Technical solution

[0009] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0010] In a first aspect, an embodiment of the present invention provides a method for preparing a manganese-zinc ferrite material, comprising the following steps:

[0011] S1, prefabricated finished product material: granulate the manganese-zinc ferrite finished products numbered A1 to An according to the different formulas numbered A1 to An, where n is an integer ≥ 2;

[0012] Among them, the manganese-zinc ferrite materials prepared by each formula correspond to different electromagnetic properties;

[0013] S2, selecting two or more of the manganese-zinc ferrite finished products numbered A1 to An and mixing them in a specified mass ratio to prepare a blend;

[0014] S3. Pressing the blend into a green embryo, and then sintering it to form a green embryo, so as to prepare a manganese-zinc ferrite material; wherein the electromagnetic properties of the manganese-zinc ferrite material prepared from the blend are different from the corresponding electromagnetic properties of the manganese-zinc ferrite material prepared from each manganese-zinc ferrite finished material contained therein.

[0015] As a preferred embodiment of the present invention, the preparation method of the manganese-zinc ferrite material, in S1, any existing manganese-zinc ferrite material formula includes a main formula and an auxiliary agent formula, the main formula totals 100 mol%, and the formula is composed of 52-54.5 mol% of Fe 2 O 3 , 33.5-40 mol % MnO and 8-12 mol % ZnO;

[0016] Based on the total weight of the main formula, the total weight of the auxiliary formula is ≤0.2%.

[0017] As a preferred embodiment of the present invention, in the preparation method of the manganese-zinc ferrite material, in S2, the specified mass ratio is determined by the electromagnetic properties corresponding to each manganese-zinc ferrite finished product material in the blend.

[0018] The electromagnetic properties include magnetic permeability, saturation magnetic flux density, Curie temperature, coercive force, remanence, inductance value, temperature coefficient, specific temperature coefficient, power loss density, and magnetocrystalline anisotropy constant.

[0019] As a preferred embodiment of the present invention, in the preparation method of the manganese-zinc ferrite material, in S2, the blend includes two numbered manganese-zinc ferrite finished product materials, and the mass ratio of the two is 1-10:1-10.

[0020] As a preferred embodiment of the present invention, in the preparation method of the manganese-zinc ferrite material, the manganese-zinc ferrite finished product materials numbered A1 to An can be sintered respectively to prepare the manganese-zinc ferrite materials numbered A1 to An, and the sintering processes of the manganese-zinc ferrite materials numbered A1 to An correspond to the sintering temperature curves numbered T1 to Tn.

[0021] In S2, if the blend is composed of the manganese-zinc ferrite finished product materials numbered Ai and Aj, where i and j are integers from 1 to n and i≠j;

[0022] Then, in S3, the number of the sintering temperature curve corresponding to the sintering process of the blend is T. As the T sintering temperature curve changes with the sintering time, the specific temperature parameters are based on at least one of the Ti sintering temperature curve and the Tj sintering temperature curve, and the floating range ≤50%.

[0023] As a preferred embodiment of the present invention, in the preparation method of the manganese-zinc ferrite material, in S3, the specific temperature parameters include heating rate, holding temperature, holding time, and cooling rate.

[0024] The holding temperature is the highest temperature range maintained during the sintering process.

[0025] As a preferred embodiment of the present invention, in the preparation method of the manganese-zinc ferrite material, the sintering processes of the manganese-zinc ferrite materials numbered A1 to An correspond to the oxygen content change curves numbered F1 to Fn of the sintering atmosphere.

[0026] In S2, if the blend is composed of the manganese-zinc ferrite finished product materials numbered Ai and Aj, where i and j are integers from 1 to n and i≠j;

[0027] Then, in S3, the oxygen content variation curve of the sintering atmosphere corresponding to the sintering process of the blend is numbered F, and the F oxygen content variation curve is determined by the Fi oxygen content variation curve, the Fj oxygen content variation curve and the T sintering temperature curve;

[0028] The F oxygen content variation curve changes with the sintering time, and the specific parameters are based on at least one of the Fi oxygen content variation curve and the Fj oxygen content variation curve, and the floating range is ≤50%.

[0029] As a preferred embodiment of the present invention, in the method for preparing the manganese-zinc ferrite material, the sintering process of the manganese-zinc ferrite materials numbered A1 to An corresponds to the green density numbered M1-Mn;

[0030] In S2, if the blended material is formed by mixing the finished manganese-zinc ferrite materials numbered Ai and Aj, where i and j are integers from 1 to n, and i≠j;

[0031] Then, in S3, the density of the green embryo pressed from the blend is based on at least one of the green embryo density Mi and the green embryo density Mj, and the floating range is ≤10%.

[0032] As a preferred embodiment of the present invention, the preparation method of the manganese-zinc ferrite material is as follows:

[0033] In S1, before granulation, the main formula material is first ball-milled and pre-calcined, and then mixed with the auxiliary agent formula material, and then ball-milled and dried for a second time.

[0034] (III) Beneficial effects

[0035] The beneficial effects of the present invention are as follows: the preparation method of a manganese-zinc ferrite material of the present invention adopts finished materials made by more than two existing formulas (the final sintering step has not been completed) to be mixed according to a specified mass ratio, and then a new manganese-zinc ferrite material is prepared by sintering. The new manganese-zinc ferrite material has new and excellent electromagnetic properties relative to different finished materials. Compared with the prior art, it can save the complicated work of adjusting many main formulas and auxiliary agent formulas in the process of optimizing the electrical properties of ferrite materials. At the same time, it refers to the sintering process of existing finished materials for sintering, avoiding the extra workload and waste of raw materials caused by repeated exploration of sintering conditions. The research and development and preparation efficiency of ferrite materials is improved, costs are saved, and it has a wide range of promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is the volume power loss density (P cv )-temperature (T) curve;

[0037] Figure 2is the volume power loss density (P cv )-temperature (T) curve. DETAILED DESCRIPTION

[0038] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0039] The method for preparing a manganese-zinc ferrite material proposed in the embodiment of the present invention aims at the technical problems of low efficiency and high cost in the research and development and preparation of existing manganese-zinc ferrites; finished materials made from two or more existing formulas (the final sintering step has not yet been completed) are mixed according to a specified mass ratio, and then a new manganese-zinc ferrite material is prepared by sintering. The new manganese-zinc ferrite material has new and excellent electromagnetic properties relative to different finished materials. Compared with the existing technology, it can save the complicated work of adjusting many main formulas and auxiliary agent formulas in the process of optimizing the electrical properties of ferrite materials. At the same time, it refers to the sintering process of existing finished materials for sintering, avoiding the extra workload and waste of raw materials caused by repeated exploration of sintering conditions. The efficiency of research and development and preparation of ferrite materials is improved, costs are saved, and it has a wide range of promotion value.

[0040] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0041] Example 1

[0042] This embodiment provides a method for preparing a manganese-zinc ferrite material, which specifically includes the following steps:

[0043] (1) Different weighing: Finished material A1 and finished material A2 were weighed at a mass ratio of 3:1, and the materials were fully mixed in a blender to obtain blend 1. The components of finished material A1 and finished material A2 are shown in Table 1. The electromagnetic properties of finished material A1 and finished material A2 are shown in Table 2.

[0044] Finished material A1 and finished material A2 are both based on the components in Table 1, wherein the main formula material is first ball-milled and pre-burned, then mixed with the auxiliary agent formula material, and then ball-milled and dried for use.

[0045] When the finished material A1 and the finished material A2 are sintered separately to prepare the manganese-zinc ferrite material, the corresponding conditions are:

[0046] 1) Green embryo pressing: The finished product materials A1 and A2 are respectively pressed into annular green embryos A1 and A2 with dimensions of 20mm * 10mm * 5mm on a 16T molding press. The density of the green embryos is 3.0 g / cm 3 ;

[0047] 2) Sintering: The annular green embryos A1 and A2 are sintered respectively under nitrogen protection. The sintering temperature is 1300 °C, and the holding time is 5 h. The oxygen partial pressure during the holding stage is 5%. The sample rings are taken out after cooling down to below 200 °C by the equilibrium atmosphere method;

[0048] The inductance factors of the two sample rings are measured respectively at -25 °C - 125 °C under 0.1 V and 10 KHz, and their temperature coefficients are calculated. The electromagnetic properties of the two sample rings are shown in Table 2.

[0049] (2) The blended material 1 is pressed into a green embryo and then sintered to prepare a manganese-zinc ferrite material with the composite properties of more than 2 kinds of finished manganese-zinc ferrite materials. Among them, the green embryo pressing conditions and sintering conditions are the same as those in the previous steps 1) and 2). The inductance factors of the manganese-zinc ferrite material with composite properties are measured respectively at -25 °C - 125 °C under 0.1 V and 10 KHz, and their temperature coefficients are calculated, as shown in Table 2 specifically.

[0050] Table 1 Formulation of the finished product material

[0051]

[0052] Table 2 Electromagnetic properties of the finished product material and the blended material

[0053]

[0054] Generally, the inductance stable operating temperature range of low temperature coefficient ferrite products is mostly -25 °C - 125 °C, and the corresponding low temperature coefficient is close to or higher than 2000×10 -6 / °C, and the high temperature coefficient is usually higher than 1000×10 -6 / °C. The low temperature specific temperature coefficient is usually higher than 1.0×10 -6 / °C, and the high temperature specific temperature coefficient is usually higher than 0.5×10 -6 / °C.

[0055] In this embodiment, referring to Table 1 and Table 2, it can be seen that the temperature coefficient and specific temperature coefficient of the blend 1 at -25°C and 125°C are significantly better than those of the finished products A1 and A2. The performance of the ferrite sample ring obtained through reasonable proportioning is far better than that of the existing products (the manganese-zinc ferrite materials prepared by separately sintering the finished products A1 and A2), and the formulations of the finished products A1 and A2 are the existing raw materials of our company, without going through the processes of main formula and auxiliary agent formula batching, as well as pre-sintering of the main formula, greatly saving production costs and improving production and R & D efficiency.

[0056] Example 2

[0057] This embodiment provides a preparation method of a manganese-zinc ferrite material, which specifically includes the following steps:

[0058] (1) Different weighing: Weigh the finished products A3 and A4 according to a mass ratio of 2:1, and fully mix the materials in a blender to obtain a blend. Among them, the components of the finished products A3 and A4 are shown in Table 3. The electromagnetic properties of the finished products A3 and A4 are shown in Table 4.

[0059] Both the finished products A3 and A4 are prepared according to the components in Table 3. Among them, the main formula materials are first subjected to primary ball milling and pre-sintering, and then doped with the auxiliary agent formula materials, and then subjected to secondary ball milling and drying to make them ready for use.

[0060] When separately sintering the finished products A3 and A4 to prepare manganese-zinc ferrite materials, the corresponding conditions are as follows:

[0061] 1) Green compact pressing: The finished products A3 and A4 are respectively pressed into annular green compacts A3 and A4 with dimensions of 20mm * 10mm * 5mm on a 16T molding press, and the green compact density is 3.0 g / cm 3 ;

[0062] 2) Sintering: The annular green compacts A3 and A4 are respectively sintered under nitrogen protection. The sintering temperature is 1270°C, and the holding time is 5h. The oxygen partial pressure during the holding stage is 4.2%. Cool down to below 200°C according to the equilibrium atmosphere method and take out the sample rings;

[0063] Measure the power loss density P of the two sample rings at 25°C - 125°C at 50KHz and 200mT respectively cv , as shown in Table 4 specifically.

[0064] (2) Press the blend into a green body, and then sinter it to prepare a manganese-zinc ferrite material with the composite properties of more than 2 kinds of finished manganese-zinc ferrite materials. Among them, the pressing conditions and sintering conditions of the green body are the same as those in the previous steps 1) and 2). The power loss density P of the two sample rings of the manganese-zinc ferrite material with composite properties is tested at 50 KHz and 200 mT respectively at 25 °C - 125 °C. cv , as shown in Table 4 specifically.

[0065] Table 3 Formulation of the finished material

[0066]

[0067] Table 4 Electromagnetic properties of the finished material and the blend

[0068]

[0069] In this embodiment, referring to Figure 1 , Table 3 and Table 4, the P cv valleys of the manganese-zinc ferrite materials prepared by separately sintering the finished material A3 and the finished material A4 are at 85 °C and 65 °C respectively, and near the valleys, P cv shows a significant increasing trend. In contrast, referring to Figure 1 , the P cv of the sample ring prepared from the blend 2 changes relatively flatly in a relatively wide temperature range and does not show an obvious increasing trend, which meets the requirements of wide temperature and low loss of manganese-zinc ferrite materials for various devices such as transformers.

[0070] Example 3

[0071] This embodiment provides a preparation method of a manganese-zinc ferrite material, which specifically includes the following steps:

[0072] (1) Different weighing: Weigh the finished material A5 and the finished material A6 according to the mass ratio of 2.5:1, and fully mix the materials in a blender to obtain a blend. Among them, the components of the finished material A5 and the finished material A6 are shown in Table 5. The electromagnetic properties of the finished material A5 and the finished material A6 are shown in Table 6.

[0073] Both the finished material A5 and the finished material A6 are in accordance with the components in Table 4. Among them, the main formula materials are first ball-milled and pre-sintered once, and then doped with the auxiliary agent formula materials, and then ball-milled and dried twice to make them ready for use.

[0074] The corresponding conditions for separately sintering the manganese-zinc ferrite materials using the finished material A5 and the finished material A6 are both:

[0075] 1) Green compact pressing: The finished materials A5 and A6 are respectively pressed into annular green compacts A5 and A6 with dimensions of 20mm * 10mm * 5mm on a 16T molding press, and the density of the green compacts is 3.0 g / cm 3 ;

[0076] 2) Sintering: The annular green compacts A5 and A6 are sintered respectively under nitrogen protection. The sintering temperature is 1285 °C, and the holding time is 4 h. The oxygen partial pressure during the holding stage is 5.3%. The sample rings are taken out after cooling down to below 200 °C by the equilibrium atmosphere method;

[0077] The power loss density P of the two sample rings is measured respectively at 50 KHz and 200 mT from 25 °C to 125 °C cv , and the inductance factor of the sample rings is measured at 0.1 V and 10 KHz from -55 °C to 125 °C, and its temperature coefficient is calculated, as shown in Table 6 specifically.

[0078] (2) The blend is pressed into a green compact and then sintered to prepare a manganese-zinc ferrite material with the composite properties of more than 2 types of finished manganese-zinc ferrite materials. Among them, the green compact pressing conditions and sintering conditions are the same as those in the previous steps 1) and 2). The power loss density P of the two sample rings of the manganese-zinc ferrite material with composite properties is measured respectively at 50 KHz and 200 mT from 25 °C to 125 °C cv , as shown in Table 6 specifically.

[0079] Table 5 Formulation of the finished material

[0080]

[0081] Table 6 Electromagnetic properties of the finished material and the blend

[0082]

[0083] In this embodiment, referring to Table 5 and Table 6, the sample ring of the manganese-zinc ferrite material prepared by sintering the finished material A5 alone has the characteristics of wide temperature range and low loss, but the high and low temperature coefficients of the magnetic permeability are too high. The sample ring of the manganese-zinc ferrite material prepared by sintering the finished material A6 alone has a lower temperature coefficient of magnetic permeability, but P cv shows an obvious increasing trend with the increase of temperature, and P cv is relatively high. The sample ring prepared from the blend 3 effectively combines the advantages of the finished materials A5 and A6, having both a lower temperature coefficient and the characteristics of wide temperature range and low loss. That is to say, according to the electromagnetic properties of the finished materials, a new manganese-zinc ferrite material can be prepared by simply mixing and firing the finished materials, thereby improving the electromagnetic properties of the manganese-zinc ferrite material, which greatly broadens the application range of the new manganese-zinc ferrite material.

[0084] 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 them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and 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. A method for preparing a manganese-zinc ferrite material, characterized in that: The following steps are involved: S1, prefabricated finished product material: granulate the manganese-zinc ferrite finished products numbered A1 to An according to the different formulas numbered A1 to An, where n is an integer ≥ 2; Among them, the manganese-zinc ferrite materials prepared by each formula correspond to different electromagnetic properties; S2, selecting two or more of the manganese-zinc ferrite finished products numbered A1 to An and mixing them in a specified mass ratio to prepare a blend; S3. Pressing the blend into a green embryo, and then sintering it to form a green embryo, so as to prepare a manganese-zinc ferrite material; wherein the electromagnetic properties of the manganese-zinc ferrite material prepared from the blend are different from the corresponding electromagnetic properties of the manganese-zinc ferrite material prepared from each manganese-zinc ferrite finished material contained therein.

2. The method for preparing the manganese-zinc ferrite material according to claim 1, characterized in that: In S1, any existing manganese-zinc ferrite material formula includes a main formula and an auxiliary agent formula, the main formula totaling 100 mol%, consisting of 52-54.5 mol% of Fe2O3, 33.5-40 mol% of MnO and 8-12 mol% of ZnO; Based on the total weight of the main formula, the total weight of the auxiliary formula is ≤0.2%.

3. The method for preparing the manganese-zinc ferrite material according to claim 2, characterized in that: In S2, the specified mass ratio is determined by the electromagnetic properties corresponding to each manganese-zinc ferrite finished material in the blend; Electromagnetic properties include magnetic permeability, saturation flux density, Curie temperature, coercivity, remanence, inductance, temperature coefficient, specific temperature coefficient, power loss density, and magnetocrystalline anisotropy constant.

4. The method for preparing the manganese-zinc ferrite material according to claim 3, characterized in that: In S2, the blend includes two types of numbered manganese-zinc ferrite finished products, and the mass ratio of the two is 1-10:1-10.

5. The method for preparing the manganese-zinc ferrite material according to claim 2, characterized in that: The manganese-zinc ferrite finished products numbered A1 to An can be sintered to prepare manganese-zinc ferrite materials numbered A1 to An, and the sintering processes of the manganese-zinc ferrite materials numbered A1 to An correspond to the sintering temperature curves numbered T1 to Tn; In S2, if the blended material is formed by mixing the manganese-zinc ferrite finished materials numbered Ai and Aj, where i and j are integers from 1 to n, and i≠j; Then, in S3, the sintering temperature curve corresponding to the sintering process of the blend is numbered T. As the sintering time progresses, the specific temperature parameters of the T sintering temperature curve are based on at least one of the Ti sintering temperature curve and the Tj sintering temperature curve, and the floating range is ≤50%.

6. The method for preparing the manganese-zinc ferrite material according to claim 5, characterized in that: In S3, the specific temperature parameters include heating rate, insulation temperature, insulation time, and cooling rate; The holding temperature is the highest temperature range maintained during the sintering process.

7. The method for preparing the manganese-zinc ferrite material according to claim 5, characterized in that: The sintering process of the manganese-zinc ferrite materials numbered A1 to An corresponds to the oxygen content variation curve of the sintering atmosphere numbered F1 to Fn; In S2, if the blended material is formed by mixing the finished manganese-zinc ferrite materials numbered Ai and Aj, where i and j are integers from 1 to n, and i≠j; Then, in S3, the oxygen content variation curve of the sintering atmosphere corresponding to the sintering process of the blend is numbered F, and the F oxygen content variation curve is determined by the Fi oxygen content variation curve, the Fj oxygen content variation curve and the T sintering temperature curve; The F oxygen content variation curve changes with the sintering time, and the specific parameters are based on at least one of the Fi oxygen content variation curve and the Fj oxygen content variation curve, and the floating range is ≤50%.

8. The method for preparing the manganese-zinc ferrite material according to claim 5, characterized in that: The sintering process of the manganese-zinc ferrite materials numbered A1 to An corresponds to the green density numbered M1-Mn; In S2, if the blended material is formed by mixing the finished manganese-zinc ferrite materials numbered Ai and Aj, where i and j are integers from 1 to n, and i≠j; Then, in S3, the density of the green embryo pressed from the blend is based on at least one of the green embryo density Mi and the green embryo density Mj, and the floating range is ≤10%.

9. The method for preparing the manganese-zinc ferrite material according to claim 1, characterized in that: In S1, before granulation, the main formula material is first ball-milled and pre-calcined, and then mixed with the auxiliary agent formula material, and then ball-milled and dried for a second time.

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