A high-performance lean iron manganese zinc ferrite material made of ground clay and a preparation method and application thereof

Abstract

This invention discloses a high-performance lean-iron manganese-zinc ferrite material prepared by grinding, its preparation method, and its application, belonging to the technical field of manganese-zinc ferrite material preparation. The preparation steps of the high-performance lean-iron manganese-zinc ferrite material prepared by grinding include: adjusting the molar ratio of Fe2O3, Mn3O4, and ZnO in the dried and pulverized grinding mud with one or two of Fe2O3, Mn3O4, and ZnO to obtain a mixed powder; adding the auxiliary component Co2O3 to the mixed powder, adding water, and ball milling to obtain a slurry; adding a binder to the slurry, stirring evenly, and drying to prepare a pre-pressed powder; pressing the pre-pressed powder into shape and sintering to obtain the high-performance lean-iron manganese-zinc ferrite material prepared by grinding. The high-performance lean-iron manganese-zinc ferrite material prepared by this invention has the characteristics of high frequency, high permeability, and high impedance, which can meet the material performance requirements of medium- and high-frequency anti-electromagnetic interference devices and solve the problem of grinding mud treatment, realizing the resource utilization of waste.

Description

Technical Field

[0001] This invention belongs to the field of manganese-zinc ferrite material preparation technology, specifically relating to a high-performance iron-poor manganese-zinc ferrite material prepared by grinding, its preparation method, and its application. Background Technology

[0002] Electromagnetic pollution from electronic and electrical appliances is increasingly impacting people's lives, causing malfunctions in electrical equipment, image flickering in displays, and communication equipment failures. Its harm in today's electronic information society is no less than that of industrial pollution such as wastewater, exhaust gas, and solid waste. Therefore, countries worldwide have established corresponding mandatory market access regulations, requiring electronic and electrical equipment to meet the electromagnetic compatibility (EMC) levels stipulated by these regulations, making electromagnetic interference (EMI) immunity modules a mandatory component in electronic and electrical appliances.

[0003] Ferrite materials with high permeability, high frequency, and high impedance are mainly used in broadband transformers, pulse transformers, and EMI suppression devices in fiber optic communication and data network technologies. With the rapid development of communication and digital technologies, miniaturization and thinning of electronic components have become current trends, thus placing higher performance demands on devices such as broadband pulse transformers, inductors, and filters. Developing multi-performance ferrite materials that possess high permeability while also exhibiting high frequency, high impedance, and high saturation magnetic flux density is one of the important research directions in the high permeability sector of the current magnetic industry.

[0004] Currently, iron-poor manganese-zinc ferrite materials possess high permeability, high frequency, and high impedance characteristics, while also possessing the low frequency and high impedance characteristics of nickel-zinc ferrite materials, thus compensating for the shortcomings of low frequency and low permeability in nickel-zinc ferrite materials.

[0005] Existing technology CN111233452A discloses a high-frequency, high-impedance iron-poor manganese-zinc ferrite with an initial permeability of about 2000 H / m, an impedance of about 40 Ω at 1 MHz, about 50 Ω at 25 MHz, about 150 Ω at 100 MHz, and about 1800 Ω at 400 MHz. Existing technology CN117303883A discloses an iron-poor, high-impedance manganese-zinc ferrite material with an initial permeability of about 2000 H / m, an impedance of about 10 Ω at 1 MHz, about 60 Ω at 25 MHz, about 120 Ω at 100 MHz, an impedance ≥1330 Ω at 500 MHz, and a saturation magnetic flux density Bs ≥422 mT at 25℃.

[0006] Transformers made from manganese-zinc ferrite cores are generally made by pairing two cores. In order to achieve inductance stability and saturation resistance, the functional surfaces of the cores are usually processed, and an air gap is opened to increase its saturation resistance. A large amount of core debris, also known as abrasive, is generated during the processing. This abrasive has always been treated as a low-end material because it is not clean to recycle and contains a lot of impurities. Summary of the Invention

[0007] The purpose of this invention is to provide a high-performance iron-manganese-zinc ferrite material prepared from milled clay, its preparation method, and its applications. This invention uses low-value milled clay as raw material to prepare a high-performance iron-manganese-zinc ferrite material with an initial permeability μi ≥ 2500 H / m at 10 kHz and 0.25 V, 2000 ± 10% H / m at 500 kHz and 0.25 V, and 1625 ± 10% H / m at 1000 kHz and 0.25 V; a standard impedance value ≥ 12 Ω at 1 MHz, ≥ 45 Ω at 5 MHz, ≥ 70 Ω at 10 MHz, ≥ 125 Ω at 30 MHz, and ≥ 150 Ω at 100 MHz; and a saturation magnetic flux density Bs ≥ 380 mT at 25 °C. The provided iron-manganese-zinc ferrite material exhibits characteristics of high frequency, high permeability, and high impedance.

[0008] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a method for preparing high-performance iron-poor manganese-zinc ferrite materials by grinding and sludge, comprising the following steps: The molar proportions of Fe2O3, Mn3O4, and ZnO in the dried and pulverized sludge are adjusted to Fe2O3: 42%–44%, Mn3O4: 37%–39%, and ZnO: 17%–21% to obtain a mixed powder. Co2O3 is added to the mixed powder, and water is added and ball-milled to obtain a slurry. A binder is added to the slurry, and after stirring evenly, it is dried to prepare a pre-compressed powder. The pre-compressed powder is pressed into a green body, and the green body is sintered to obtain the high-performance iron-poor manganese-zinc ferrite material made from the sludge.

[0009] Preferably, the amount of Co2O3 added is 0.5% to 1% of the mass of the mixed powder.

[0010] Preferably, during the ball milling process of the slurry, the material-to-water mass ratio is 1:(1-1.1), and the average particle size of the powder in the slurry is 0.9-1.1 μm after ball milling.

[0011] Preferably, the adhesive is a polyvinyl alcohol (PVA) solution.

[0012] More preferably, the concentration of the PVA solution is 8 wt%, and the amount of PVA solution added is 10% of the mass of the slurry.

[0013] Preferably, the average particle size of the pre-compressed powder is 20–50 μm.

[0014] Preferably, a lubricant is added to the pre-compressed powder during the compression molding process.

[0015] More preferably, the lubricant is zinc stearate, and the amount added is 2‰ of the mass of the pre-compressed powder.

[0016] Preferably, the density of the green body is 3 ± 0.05 g / cm³. 3 .

[0017] Preferably, the sintering is curve sintering, which specifically involves: raising the temperature from room temperature to 1280℃ to 1330℃ in air for 5 to 6 hours, holding at 1280℃ to 1330℃ for 8 to 10 hours, with an oxygen content of 2 to 3 vol% during the holding period, and then cooling to room temperature in a balanced atmosphere at a cooling rate of 3 to 5℃ / min.

[0018] In this invention, room temperature refers to a temperature of 10–30°C.

[0019] Generally speaking, the oxygen partial pressure (P) in the surrounding atmosphere O2 When appropriate, oxides and ferrites neither oxidize nor reduce, or in other words, the absorbed oxygen equals the released oxygen, reaching a state of chemical equilibrium. The oxygen partial pressure at this point is called the equilibrium oxygen partial pressure. The equilibrium atmosphere is a function of temperature. Because the oxygen density inside the ferrite sample is greater than that in the surrounding atmosphere, as the temperature rises, the oxygen decomposition pressure inside the ferrite sample increases faster than the oxygen partial pressure in the surrounding atmosphere. As a result, the ferrite sample releases oxygen, and vice versa. To ensure that the composition, ionic state, and microstructure of the ferrite meet the requirements, ferrite sintering must be carried out in an equilibrium atmosphere.

[0020] The curve sintering of the present invention can solve the problems of glue removal cracking, product over-oxidation or over-reduction during the sintering process, and ensure the excellent electromagnetic properties of the product.

[0021] The second technical solution of the present invention provides a high-performance low-iron manganese-zinc ferrite material prepared by grinding according to the above-mentioned preparation method of high-performance low-iron manganese-zinc ferrite material prepared by grinding.

[0022] The third technical solution of the present invention provides an application of the above-mentioned high-performance iron-poor manganese-zinc ferrite material prepared by grinding mud in the preparation of high-frequency electromagnetic interference suppression devices.

[0023] The beneficial technical effects of the present invention are as follows: The high-performance lean iron-manganese-zinc ferrite material prepared by this invention has an initial permeability μi of ≥2500H / m at 10kHz and 0.25V, 2000±10%H / m at 500kHz and 0.25V, and 1625±10%H / m at 1000kHz and 0.25V; its standard impedance value is ≥12Ω at 1MHz, ≥45Ω at 5MHz, ≥70Ω at 10MHz, ≥125Ω at 30MHz, and ≥150Ω at 100MHz; and its saturation magnetic flux density Bs at 25℃ is ≥380mT. This high-performance lean iron-manganese-zinc ferrite material prepared by grinding can meet the material performance requirements of mid-to-high frequency electromagnetic interference suppression devices and solve the problem of grinding mud disposal, realizing the resource utilization of waste. Detailed Implementation

[0024] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0025] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0026] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0027] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0028] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0029] This invention provides a method for preparing high-performance iron-poor manganese-zinc ferrite materials by grinding and slurry preparation, comprising the following steps: The molar proportions of Fe2O3, Mn3O4, and ZnO in the dried and pulverized sludge are adjusted to Fe2O3: 42%–44%, Mn3O4: 37%–39%, and ZnO: 17%–21% to obtain a mixed powder. Co2O3 is added to the mixed powder, and water is added and ball-milled to obtain a slurry. A binder is added to the slurry, and after stirring evenly, it is dried to prepare a pre-compressed powder. The pre-compressed powder is pressed into a green body, and the green body is sintered to obtain the high-performance iron-poor manganese-zinc ferrite material made from the sludge.

[0030] Furthermore, the amount of Co2O3 added is 0.5% to 1% of the mass of the mixed powder.

[0031] Furthermore, during the ball milling process of the slurry, the material-to-water mass ratio is 1:(1-1.1), and the average particle size of the powder in the slurry is 0.9-1.1 μm after ball milling.

[0032] Furthermore, the adhesive is a PVA solution.

[0033] Furthermore, the concentration of the PVA solution is 8 wt%, and the amount of PVA solution added is 10% of the mass of the slurry.

[0034] Furthermore, the average particle size of the pre-compressed powder is 20–50 μm.

[0035] Furthermore, a lubricant was added to the pre-compressed powder during the compression molding process.

[0036] Furthermore, the lubricant is zinc stearate, and the amount added is 2‰ of the mass of the pre-compressed powder.

[0037] Furthermore, the density of the green body is 3 ± 0.05 g / cm³. 3 .

[0038] Furthermore, the sintering is a curve sintering, which specifically involves: raising the temperature from room temperature to 1280℃ to 1330℃ in air for 5 to 6 hours, holding at 1280℃ to 1330℃ for 8 to 10 hours with an oxygen content of 2 to 3 vol% during the holding period, and then cooling to room temperature in an equilibrium atmosphere at a cooling rate of 3 to 5℃ / min.

[0039] The present invention also provides a high-performance low-iron-manganese-zinc ferrite material prepared by grinding according to the above-described method for preparing high-performance low-iron-manganese-zinc ferrite material; and the application of the high-performance low-iron-manganese-zinc ferrite material prepared by grinding in the preparation of high-frequency electromagnetic interference suppression devices.

[0040] Example 1 1) Take clean grinding mud and dry it. Put the dried grinding mud into a pulverizer and pulverize it to obtain grinding mud powder.

[0041] 2) Perform principal component analysis on the sludge powder from step 1) (analysis results: Fe2O3: 69.07 mol%, Mn3O4: 17.71 mol%, ZnO: 13.22 mol%). Add one or two of Fe2O3, Mn3O4 and ZnO to compensate for the target of Fe2O3: 43.8 mol%, Mn3O4: 37.8 mol%, ZnO: 18.4 mol%, to obtain a mixed powder.

[0042] 3) Add 0.5% (by weight) of Co2O3 to the mixed powder obtained in step 2), then ball mill to obtain a slurry; wherein the mass ratio of ball milling material to water is 1:1, the mass ratio of material to ball milling material is 1:4 (the balls are steel balls with a diameter of φ=3mm), the ball milling time is 120 min, and the average particle size of the powder in the slurry is 1.0 μm. Add 10% (by weight) of PVA solution (concentration of 8wt%) to the slurry, stir for 15 min, and spray dry to obtain pre-compressed powder.

[0043] 4) Add zinc stearate to the pre-compressed powder obtained in step 3) at a rate of 2 wt‰, then press and shape the powder, controlling the green density to 3 g / cm³. 3 .

[0044] 5) The green body obtained in step 4) is subjected to curved sintering: heating stage: 25℃~1300℃, heated in air for 6 hours; holding stage: 1300℃, oxygen content 2 vol% (the remainder is nitrogen), held for 9 hours; cooling stage: 1300℃~25℃, cooled in a balanced atmosphere (oxygen content 2 vol%, the remainder is nitrogen) at a rate of 5℃ / min. High-performance lean iron-manganese-zinc ferrite material is obtained by grinding.

[0045] Examples 2-5 The differences in parameter settings between Example 1 and Example 2 are shown in Table 1.

[0046] The performance of the high-performance iron-poor manganese-zinc ferrite materials prepared by grinding in Examples 1-5 was determined. The test items and test results are shown in Table 1.

[0047] Table 1. Performance of high-performance iron-poor manganese-zinc ferrite materials prepared by grinding in Examples 1-5 The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing high-performance lean iron-manganese-zinc ferrite material by grinding and slurry preparation, characterized in that, Includes the following steps: The molar proportions of Fe2O3, Mn3O4, and ZnO in the dried and pulverized sludge are adjusted to Fe2O3: 42%–44%, Mn3O4: 37%–39%, and ZnO: 17%–21% to obtain a mixed powder. Co2O3 is added to the mixed powder, and water is added and ball-milled to obtain a slurry. A binder is added to the slurry, and after stirring evenly, it is dried to prepare a pre-compressed powder. The pre-compressed powder is pressed into a green body, and the green body is sintered to obtain the high-performance iron-poor manganese-zinc ferrite material made from the sludge.

2. The method for preparing high-performance lean iron manganese zinc ferrite material by grinding and sludge according to claim 1, characterized in that, The amount of Co2O3 added is 0.5% to 1% of the mass of the mixed powder.

3. The method for preparing high-performance lean iron-manganese-zinc ferrite material by grinding according to claim 1, characterized in that, During the ball milling process of the slurry, the material-to-water mass ratio is 1:(1-1.1), and the average particle size of the powder in the slurry is 0.9-1.1 μm after ball milling.

4. The method for preparing high-performance lean iron manganese zinc ferrite material by grinding and sludge according to claim 1, characterized in that, The adhesive is a polyvinyl alcohol solution.

5. The method for preparing high-performance lean iron-manganese-zinc ferrite material by grinding according to claim 1, characterized in that, The average particle size of the pre-compressed powder is 20–50 μm.

6. The method for preparing high-performance lean iron manganese zinc ferrite material by grinding and sludge according to claim 1, characterized in that, Lubricant was added to the pre-compressed powder during the pressing process.

7. The method for preparing high-performance lean iron-manganese-zinc ferrite material by grinding according to claim 1, characterized in that, The density of the green body is 3 ± 0.05 g / cm³. 3 .

8. The method for preparing high-performance lean iron manganese zinc ferrite material by grinding according to claim 1, characterized in that, The sintering is a curve sintering, which specifically involves: heating from room temperature to 1280℃ to 1330℃ in air for 5 to 6 hours, holding at 1280℃ to 1330℃ for 8 to 10 hours with an oxygen content of 2 to 3 vol% during the holding period, and then cooling to room temperature in a balanced atmosphere at a cooling rate of 3 to 5℃ / min.

9. A high-performance low-iron manganese-zinc ferrite material prepared by the method of preparing high-performance low-iron manganese-zinc ferrite material by grinding according to any one of claims 1 to 8.

10. The application of the high-performance lean iron manganese zinc ferrite material prepared by grinding as described in claim 9 in the preparation of high-frequency electromagnetic interference suppression devices.

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