A manganese-zinc ferrite material and a method for producing the same

Abstract

The application relates to a manganese-zinc ferrite material and a preparation method thereof, the manganese-zinc ferrite material comprising a main component and an auxiliary component; the main component comprises ZnO 19.6-21.48 mol%, MnO 26.02-29.52 mol% and the balance of Fe2O3 in terms of molar percentage; and the auxiliary component comprises CaCO3 100-2000 ppm, Bi2O3 200-2000 ppm, MoO 100-2000 ppm and CoO 100-1500 ppm, with the main component as a reference. The manganese-zinc ferrite material provided by the application has high magnetic permeability, high Curie temperature (>=135 DEG C), wide temperature, wide frequency, low temperature coefficient characteristics and the like by designing the range of the main component and the auxiliary component, so that the mu (25 DEG C-60 DEG C) reaches the range of 15000-16000 and has a lower temperature coefficient.

Description

Technical Field

[0001] This invention relates to the field of ferrites, specifically to a manganese-zinc ferrite material and its preparation method. Background Technology

[0002] Currently, high-permeability manganese-zinc ferrites are widely used in electronic signal transmission, electromagnetic interference suppression technology, and environmental protection and energy conservation. With the rapid development of the electronic information industry, including communications, computers, and networks, and the advancements in high-frequency, high-speed integrated circuits and microelectromechanical systems (MEMS), the total power density of electronic components is increasing, leading to a greater demand for miniaturization and integration. However, as electronic components become smaller, heat flux density increases dramatically, resulting in a significant increase in the operating temperature around the components. This poses a significant challenge to the stable operation of electronic components in high-temperature environments. Therefore, the development of high Curie temperature materials is required. With the development of electronic devices, the demand for materials is increasingly trending towards multifunctionality: manganese-zinc ferrites that combine high permeability, wide temperature range, wide frequency range, low temperature coefficient, and high Curie temperature.

[0003] For example, CN104628371A discloses a manganese-zinc ferrite with high initial permeability and high Curie temperature. Its main components are 51-54 mol% iron oxide, 20-26 mol% zinc oxide, and the remainder manganese oxide. The auxiliary agents are 50-300 ppm calcium oxide, 10-800 ppm bismuth oxide, 20-1500 ppm titanium dioxide, and 10-500 ppm titanium dioxide. Within this composition range, the Curie temperature for permeability is greater than 135℃, but the permeability is far below 15000 (10 kHz, 0.25 mT). It is evident that achieving an initial permeability of over 15000 and a Curie temperature greater than or equal to 135℃ is very difficult.

[0004] For example, CN103833346A discloses a broadband manganese-zinc ferrite material and its preparation method. Iron oxide is in the range of 52.0-53.0 mol%, zinc oxide is in the range of 20.0-22.5 mol%, and the remainder is manganese oxide. The Bs (25℃) is 462 mT, although the Curie temperature reaches 136℃. However, the initial permeability μi (25℃, 10 kHz, 200 kHz) is <14000, indicating a relatively low initial permeability.

[0005] It is evident that existing manganese-zinc ferrite materials still suffer from low magnetic permeability and low Curie temperature. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of this invention is to provide a manganese zinc ferrite material and its preparation method, so as to solve the problems of low magnetic permeability and low Curie temperature that manganese zinc ferrite materials still have.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a manganese-zinc ferrite material, the manganese-zinc ferrite material comprising a main component and an auxiliary component;

[0009] The main components, in molar percentage, include ZnO 19.6-21.48 mol%, MnO 26.02-29.52 mol%, with the balance being Fe2O3;

[0010] The auxiliary components include: CaCO3 100-2000ppm, Bi2O3 200-2000ppm, MoO 100-2000ppm, and CoO 100-1500ppm, based on the main component.

[0011] The manganese-zinc ferrite material provided by this invention, through the range of the main formula and the range of auxiliary components, can produce a manganese-zinc ferrite material with high magnetic permeability, high Curie temperature (≥135℃), wide temperature range, wide frequency range, and low temperature coefficient. Specifically, cobalt is added as an auxiliary agent, and the content of Fe in the main formula is reduced, strictly controlling the proportions of iron, manganese, and zinc to ensure high magnetic permeability. Furthermore, by adding cobalt and rationally proportioning the iron element in the main components after sintering, the position of the second peak is adjusted to flatten the temperature curve, achieving a μi (25℃-60℃) within the range of 15000-16000 with a low temperature coefficient.

[0012] In this invention, the ZnO content in the main component of the manganese-zinc ferrite material is 19.6-21.48 mol%, for example, it can be 19.6 mol%, 19.7 mol%, 19.8 mol%, 19.9 mol%, 20 mol%, 20.1 mol%, 20.2 mol%, 20.3 mol%, 20.4 mol%, 20.5 mol%, 20.6 mol%, 20.7 mol%, 20.8 mol%, 20.9 mol%, 21 mol%, 21.1 mol%, 21.2 mol%, 21.3 mol%, 21.4 mol%, or 21.48 mol%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0013] In this invention, the main component of the manganese-zinc ferrite material contains MnO in a molar percentage of 26.02-29.52 mol%, for example, 26.02 mol%, 26.2 mol%, 26.4 mol%, 26.6 mol%, 26.8 mol%, 27 mol%, 27.2 mol%, 27.4 mol%, 27.6 mol%, 27.8 mol%, 28 mol%, 28.2 mol%, 28.4 mol%, 28.6 mol%, 28.8 mol%, 29 mol%, 29.2 mol%, 29.4 mol%, or 29.52 mol%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0014] In this invention, based on the main component, the content of CaCO3 in the auxiliary component is 100-2000 ppm, for example, it can be 100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm, 800 ppm, 900 ppm, 1000 ppm, 1100 ppm, 1200 ppm, 1300 ppm, 1400 ppm, 1500 ppm, 1600 ppm, 1700 ppm, 1800 ppm, 1900 ppm or 2000 ppm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0015] In this invention, based on the main component, the content of Bi2O3 in the auxiliary component is 200-2000 ppm, for example, it can be 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm, 800 ppm, 900 ppm, 1000 ppm, 1100 ppm, 1200 ppm, 1300 ppm, 1400 ppm, 1500 ppm, 1600 ppm, 1700 ppm, 1800 ppm, 1900 ppm or 2000 ppm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0016] In this invention, based on the main component, the content of MoO in the auxiliary component is 100-2000 ppm, for example, it can be 100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm, 800 ppm, 900 ppm, 1000 ppm, 1100 ppm, 1200 ppm, 1300 ppm, 1400 ppm, 1500 ppm, 1600 ppm, 1700 ppm, 1800 ppm, 1900 ppm or 2000 ppm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0017] In this invention, based on the main component, the content of CoO in the auxiliary component is 100-1500 ppm, for example, it can be 100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm, 800 ppm, 900 ppm, 1000 ppm, 1100 ppm, 1200 ppm, 1300 ppm, 1400 ppm or 1500 ppm, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0018] As a preferred technical solution of the present invention, the manganese-zinc ferrite material includes a main component and an auxiliary component;

[0019] The main components, in terms of molar percentage, include ZnO 20-21.2 mol%, MnO 27-28 mol%, with the balance being Fe2O3;

[0020] The auxiliary components include: CaCO3 200-400ppm, Bi2O3 450-600ppm, MoO 200-800ppm, and CoO 1000-1500ppm, based on the main component.

[0021] In a second aspect, the present invention provides a method for preparing the manganese-zinc ferrite material as described in the first aspect, the method comprising:

[0022] Prepare the main ingredients and auxiliary ingredients according to the formula;

[0023] The main component material is sequentially ball-milled, dried and pre-calcined, then mixed with auxiliary component material, sand-milled and dried to obtain ferrite mixture;

[0024] The obtained ferrite mixture was subjected to heat treatment in sequence, then mixed with a binder and granulated to obtain ferrite granules. After sintering in a mixed atmosphere and cooling, manganese-zinc ferrite material was obtained.

[0025] In this invention, the cooling after sintering is carried out under equilibrium oxygen partial pressure.

[0026] As a preferred technical solution of the present invention, the ball milling method is wet ball milling.

[0027] Preferably, the mass ratio of material to grinding balls in the ball mill is 1:(7-8), for example, it can be 1:7, 1:7.1, 1:7.2, 1:7.3, 1:7.4, 1:7.5, 1:7.6, 1:7.7, 1:7.8, 1:7.9 or 1:8, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0028] Preferably, the ball milling time is 30-50 minutes, for example, it can be 30 minutes, 31 minutes, 32 minutes, 33 minutes, 34 minutes, 35 minutes, 36 minutes, 37 minutes, 38 minutes, 39 minutes, 40 minutes, 41 minutes, 42 minutes, 43 minutes, 44 minutes, 45 minutes, 46 minutes, 47 minutes, 48 ​​minutes, 49 minutes, or 50 minutes, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0029] Preferably, the preheating temperature is 700-800℃, for example, it can be 700℃, 710℃, 720℃, 730℃, 740℃, 750℃, 760℃, 770℃, 780℃, 790℃ or 800℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0030] Preferably, the preheating time is 2-3 hours, for example, it can be 2 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours or 3 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0031] In this invention, pre-firing makes the additives more evenly distributed, thereby achieving high initial permeability, wide temperature range, and low temperature coefficient of Mn-Zn ferrite material.

[0032] As a preferred technical solution of the present invention, the sanding method is wet sanding.

[0033] Preferably, the grinding time is 70-90 minutes, for example, it can be 70 minutes, 71 minutes, 72 minutes, 73 minutes, 74 minutes, 75 minutes, 76 minutes, 77 minutes, 78 minutes, 79 minutes, 80 minutes, 81 minutes, 82 minutes, 83 minutes, 84 minutes, 85 minutes, 86 minutes, 87 minutes, 88 minutes, 89 minutes or 90 minutes, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0034] As a preferred technical solution of the present invention, the heat treatment temperature is 700-850℃, for example, it can be 700℃, 710℃, 720℃, 730℃, 740℃, 750℃, 760℃, 770℃, 780℃, 790℃, 800℃, 810℃, 820℃, 830℃, 840℃ or 850℃, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0035] Preferably, the heat treatment time is 3-3.5 hours, for example, 3 hours, 3.1 hours, 3.2 hours, 3.3 hours, 3.4 hours or 3.5 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0036] As a preferred embodiment of the present invention, the adhesive comprises polyvinyl alcohol.

[0037] Preferably, the amount of adhesive added is 8-10% of the mass of the ferrite mixture, for example, it can be 8%, 8.1%, 8.2%, 8.3%, 8.4%, 8.5%, 8.6%, 8.7%, 8.8%, 8.9%, 9%, 9.1%, 9.2%, 9.3%, 9.4%, 9.5%, 9.6%, 9.7%, 9.8%, 9.9% or 10%, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0038] As a preferred technical solution of the present invention, the mixed atmosphere includes a protective gas and oxygen, and the volume percentage of oxygen is 3-21%, for example, it can be 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20% or 21%, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0039] Preferably, the protective gas includes one or a combination of at least two of nitrogen, helium, neon, or argon.

[0040] As a preferred technical solution of the present invention, the sintering includes a first sintering;

[0041] Preferably, the first sintering is performed at 1280-1350°C for 4-10 hours in a mixed atmosphere with an oxygen volume percentage of 3-8%.

[0042] In this invention, the volume percentage of oxygen in the mixed atmosphere during the first sintering is 3-8%, for example, it can be 3%, 3.2%, 3.4%, 3.6%, 3.8%, 4%, 4.2%, 4.4%, 4.6%, 4.8%, 5%, 5.2%, 5.4%, 5.6%, 5.8%, 6%, 6.2%, 6.4%, 6.6%, 6.8%, 7%, 7.2%, 7.4%, 7.6%, 7.8%, or 8%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0043] In this invention, the first sintering temperature is 1280-1350℃, for example, it can be 1280℃, 1285℃, 1290℃, 1295℃, 1300℃, 1305℃, 1310℃, 1315℃, 1320℃, 1325℃, 1330℃, 1335℃, 1340℃, 1345℃ or 1350℃, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0044] In this invention, the first sintering time is 4-10h, for example, it can be 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, 9.5h or 10h, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0045] Preferably, the process includes a second sintering and a third sintering performed sequentially before the first sintering.

[0046] In this invention, the use of specific multi-stage sintering is beneficial to further improve the performance of the obtained manganese-zinc ferrite material.

[0047] In this invention, when sintering is multi-stage sintering, the first sintering time can be 4-8 hours, for example, it can be 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours or 8 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0048] Preferably, the second sintering is performed at 600-700°C for 1-3 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%.

[0049] In this invention, the volume percentage of oxygen in the mixed atmosphere of the second sintering is 19-21%, for example, it can be 19%, 19.1%, 19.2%, 19.3%, 19.4%, 19.5%, 19.6%, 19.7%, 19.8%, 19.9%, 20%, 20.1%, 20.2%, 20.3%, 20.4%, 20.5%, 20.6%, 20.7%, 20.8%, 20.9%, or 21%, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0050] In this invention, the second sintering temperature is 600℃-700℃, for example, it can be 600℃, 610℃, 620℃, 630℃, 640℃, 650℃, 660℃, 670℃, 680℃, 690℃ or 700℃, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0051] In this invention, the second sintering time is 1-3 hours, for example, it can be 1 hour, 1.1 hours, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours, 2 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours, or 3 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0052] Preferably, the third sintering is performed at 1000-1100°C for 4-8 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%.

[0053] In this invention, the volume percentage of oxygen in the mixed atmosphere of the third sintering is 19-21%, for example, it can be 19%, 19.1%, 19.2%, 19.3%, 19.4%, 19.5%, 19.6%, 19.7%, 19.8%, 19.9%, 20%, 20.1%, 20.2%, 20.3%, 20.4%, 20.5%, 20.6%, 20.7%, 20.8%, 20.9%, or 21%, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0054] In this invention, the third sintering temperature is 1000-1100℃, for example, it can be 1000℃, 1010℃, 1020℃, 1030℃, 1040℃, 1050℃, 1060℃, 1070℃, 1080℃, 1090℃ or 1100℃, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0055] In this invention, the third sintering time is 4-8 hours, for example, it can be 4 hours, 4.2 hours, 4.4 hours, 4.6 hours, 4.8 hours, 5 hours, 5.2 hours, 5.4 hours, 5.6 hours, 5.8 hours, 6 hours, 6.2 hours, 6.4 hours, 6.6 hours, 6.8 hours, 7 hours, 7.2 hours, 7.4 hours, 7.6 hours, 7.8 hours, or 8 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0056] As a preferred technical solution of the present invention, the preparation method includes:

[0057] Prepare the main ingredients and auxiliary ingredients according to the formula;

[0058] The main component material is sequentially ball-milled, dried and pre-calcined, then mixed with auxiliary component material, sand-milled and dried to obtain ferrite mixture;

[0059] The obtained ferrite mixture was subjected to heat treatment in sequence, then mixed with binder and granulated to obtain ferrite granules. After sintering in a mixed atmosphere and cooling, manganese-zinc ferrite material was obtained.

[0060] The ball milling method is wet ball milling; the mass ratio of material to grinding balls in the ball milling is 1:(7-8); the ball milling time is 30-50 min; the pre-firing temperature is 700-800℃; the pre-firing time is 2-3 h; the sand milling method is wet sand milling; the sand milling time is 70-90 min; the heat treatment temperature is 700-850℃; the heat treatment time is 3-3.5 h; the binder includes polyvinyl alcohol; the amount of binder added is 8-10% of the mass of the ferrite mixture; the mixing atmosphere includes a protective gas and oxygen, with the oxygen volume percentage being 3-21%; the protective gas includes one or a combination of at least two of nitrogen, helium, neon, or argon.

[0061] The sintering includes a second sintering, a third sintering, and a first sintering performed sequentially.

[0062] The second sintering is performed at 600-700℃ for 1-3 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%; the third sintering is performed at 1000-1100℃ for 4-8 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%; the first sintering is performed at 1280-1350℃ for 4-10 hours in a mixed atmosphere with an oxygen volume percentage of 3-8%.

[0063] Compared with existing technical solutions, the present invention has the following beneficial effects:

[0064] The technical solution of this invention prepares a manganese-zinc ferrite material with high magnetic permeability, high Curie temperature, wide temperature range, wide frequency range, and low temperature coefficient by limiting the range of the main formula and auxiliary components, and controlling the parameters of its low-temperature pre-firing and sintering processes. This achieves high magnetic permeability, wide temperature range, and low temperature coefficient manganese-zinc ferrite at low cost. Specifically, within the temperature range of 0-60℃, it exhibits a low temperature coefficient within the magnetic permeability range of 15000-16000, a Curie temperature ≥136℃, and an initial magnetic permeability (25℃, 10KHz, 100KHz) μi ≥15200. Detailed Implementation

[0065] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0066] Example 1

[0067] The designed formula is Fe2O3 52.21mol%, MnO 26.31mol%, ZnO 21.48mol%. After the main components are accurately weighed, they are put into a ball mill for ball milling (the mass ratio of material to grinding balls is 1:7.5) and mixed for 40 minutes until uniform. After drying in an oven, the pre-calcined powder is obtained by pre-calcining at 750℃ for 2.5 hours. Then, the designed auxiliary components (the auxiliary components are calculated based on the total amount of the main components, i.e., based on the main components) are added to the pre-calcined powder: Bi2O3 450ppm, CaCO3 200ppm, MoO 200ppm, CoO 1000ppm.

[0068] The material was sand-milled for 90 minutes, then dried and heat-treated at 750℃ for 3.2 hours. 8 wt% polyvinyl alcohol (based on the mass of the heat-treated material) was then mixed with the heat-treated material to obtain ferrite granules, which were then sieved. The ferrite granules were pressed into blanks with dimensions of H25×15×8 mm. These blanks were then sintered at 600℃ for 2 hours under N2 conditions with an oxygen content of 21 vol% (comprising oxygen and nitrogen), followed by sintering at 1100℃ for 6 hours under N2 conditions with an oxygen content of 21 vol% (comprising oxygen and nitrogen), and finally sintered at 1300℃ for 7 hours under N2 conditions with an oxygen content of 5.5 vol% (comprising oxygen and nitrogen). The mixture was then cooled under equilibrium oxygen pressure to obtain powder cores for testing.

[0069] The properties of the obtained materials are detailed in Table 1.

[0070] Example 2

[0071] The designed formula is Fe2O3 51.10mol%, MnO 26.44mol%, ZnO 22.46mol%. After the main components are accurately weighed, they are ball-milled (material to grinding balls mass ratio of 1:7) for 30 minutes to achieve uniformity. After drying in an oven, the mixture is pre-calcined at 700℃ for 3 hours to obtain pre-calcined material. Auxiliary components (based on the total amount of main components) are added to the pre-calcined material: CaCO3 400ppm, Bi2O3 600ppm, MoO 200ppm, and CoO 1500ppm.

[0072] The material was sand-milled for 70 minutes, then dried and heat-treated at 850℃ for 3 hours. 8 wt% polyvinyl alcohol (based on the mass of the heat-treated material) was then mixed with the heat-treated material to obtain ferrite granules, which were then sieved. The ferrite granules were pressed into blanks with dimensions of H25×15×8 mm. These blanks were then sintered at 600℃ for 3 hours under N2 conditions with an oxygen content of 19 vol% (gas composed of oxygen and nitrogen), sintered at 1000℃ for 4 hours under N2 conditions with an oxygen content of 19 vol% (gas composed of oxygen and nitrogen), and then sintered at 1340℃ for 4 hours under N2 conditions with an oxygen content of 3 vol% (gas composed of oxygen and nitrogen). The mixture was then cooled under balanced oxygen partial pressure to obtain powder cores for testing.

[0073] The properties of the obtained materials are detailed in Table 1.

[0074] Example 3

[0075] The designed formula is Fe2O3 52.32mol%, MnO 26.48mol%, ZnO 21.20mol%. After the main components are accurately weighed, they are ball-milled (material to grinding balls mass ratio of 1:8) for 50 minutes to achieve uniformity. After drying in an oven, the mixture is pre-calcined at 800℃ for 2 hours to obtain pre-calcined material. Auxiliary components (auxiliary components are calculated based on the total amount of main components) are added to the pre-calcined material: CaCO3 200ppm, Bi2O3 600ppm, MoO 200ppm, and CoO 1500ppm.

[0076] The material was sand-milled for 90 minutes, then dried and heat-treated at 700℃ for 3.5 hours. Afterwards, it was spray-granulated to obtain ferrite particles, which were then sieved. The ferrite particles were pressed into blanks with dimensions of H25×15×8. These blanks were then sintered at 700℃ for 1 hour under N2 conditions with an oxygen content (composed of oxygen and nitrogen) of 20 vol%. Next, they were sintered at 1100℃ for 8 hours under N2 conditions with an oxygen content (composed of oxygen and nitrogen) of 8 vol%. Finally, they were sintered at 1280℃ for 10 hours under balanced oxygen partial pressure. The resulting powder cores were then tested.

[0077] The properties of the obtained materials are detailed in Table 1.

[0078] Example 4

[0079] The only difference from Example 1 is that a second sintering is not performed, that is, sintering at 600°C for 2 hours is not performed under conditions where the oxygen content (the gas consists of oxygen and nitrogen) is controlled at 21 vol%.

[0080] The properties of the obtained materials are detailed in Table 1.

[0081] Example 5

[0082] The only difference from Example 1 is that the third sintering is not performed, that is, the sintering at 1100°C for 6 hours is not performed under the condition that the oxygen content (the gas is composed of oxygen and nitrogen) is controlled at 21 vol% by N2.

[0083] The properties of the obtained materials are detailed in Table 1.

[0084] Example 6

[0085] The only difference from Example 1 is that the second and third sintering are not performed. That is, instead of sintering at 600°C for 2 hours under conditions where the oxygen content (gas is composed of oxygen and nitrogen) is controlled at 21 vol%, the sample is sintered at 1100°C for 6 hours under conditions where the oxygen content (gas is composed of oxygen and nitrogen) is controlled at 21 vol%.

[0086] The properties of the obtained materials are detailed in Table 1.

[0087] Example 7

[0088] The only difference from Example 1 is that the auxiliary components do not contain MoO.

[0089] The properties of the obtained materials are detailed in Table 1.

[0090] Example 8

[0091] The only difference from Example 1 is that CoO is replaced with an equal amount of Co2O3.

[0092] The properties of the obtained materials are detailed in Table 1.

[0093] Example 9

[0094] The only difference from Example 1 is that CaCO3 is replaced with an equal amount of CaO.

[0095] The properties of the obtained materials are detailed in Table 1.

[0096] Example 10

[0097] The only difference from Example 1 is that the ZnO content is adjusted to 12 mol%.

[0098] The properties of the obtained materials are detailed in Table 1.

[0099] In the above embodiments, the performance testing of the obtained material is carried out by placing 10 turns of the sample winding (diameter of 0.35 mm) into a high and low temperature oven and gradually heating it to the set temperature (0℃, 25℃, 40℃, 60℃). Each section is kept at the temperature for 30 minutes, and then the CH3302LCR testing equipment is used for testing.

[0100] Table 1

[0101]

[0102]

[0103] The results from the above embodiments demonstrate that the manganese-zinc ferrite material provided by this invention, through the range of the main formulation and the range of auxiliary components, can produce a manganese-zinc ferrite material with high magnetic permeability, high Curie temperature (≥135℃), wide temperature range, wide frequency range, and low temperature coefficient. Specifically, the addition of cobalt as an auxiliary agent, combined with a reduction in the Fe content of the main formulation, and strict control of the proportions of iron, manganese, and zinc, ensures high magnetic permeability. Furthermore, the addition of cobalt and a reasonable ratio of iron in the main components after sintering, adjusting the position of the two peaks and flattening the temperature curve, achieves a μi (25℃-60℃) within the range of 15000-16000 with a low temperature coefficient.

[0104] The present invention is described in detail through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0105] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0106] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0107] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A manganese-zinc ferrite material, characterized in that, The manganese-zinc ferrite material includes a main component and auxiliary components; The main components, in molar percentage, include ZnO 19.6-21.48 mol%, MnO 26.02-29.52 mol%, and the balance being Fe2O3; The auxiliary components include: CaCO3 100-2000ppm, Bi2O3 200-2000ppm, MoO2 100-2000ppm, CoO 1000-1500ppm, based on the main component; The manganese-zinc ferrite material is prepared by the following method, the method comprising: Prepare the main ingredients and auxiliary ingredients according to the formula; The main component material is sequentially ball-milled, dried and pre-calcined, then mixed with auxiliary component material, sand-milled and dried to obtain ferrite mixture; The obtained ferrite mixture was subjected to heat treatment in sequence, then mixed with binder and granulated to obtain ferrite granules. After sintering in a mixed atmosphere and cooling, manganese zinc ferrite material was obtained. The sintering process includes a second sintering, a third sintering, and a first sintering, performed sequentially.

2. The manganese-zinc ferrite material as described in claim 1, characterized in that, The manganese-zinc ferrite material includes a main component and auxiliary components; The main components, in terms of molar percentage, include ZnO 20-21.2 mol%, MnO 27-28 mol%, with the balance being Fe2O3; The auxiliary components include: CaCO3 200-400ppm, Bi2O3 450-600ppm, MoO2 200-800ppm, and CoO 1000-1500ppm, based on the main component.

3. A method for preparing the manganese-zinc ferrite material as described in claim 1, characterized in that, The preparation method includes: Prepare the main ingredients and auxiliary ingredients according to the formula; The main component material is sequentially ball-milled, dried and pre-calcined, then mixed with auxiliary component material, sand-milled and dried to obtain ferrite mixture; The obtained ferrite mixture was subjected to heat treatment in sequence, then mixed with binder and granulated to obtain ferrite granules. After sintering in a mixed atmosphere and cooling, manganese zinc ferrite material was obtained. The sintering process includes a second sintering, a third sintering, and a first sintering, performed sequentially.

4. The preparation method according to claim 3, characterized in that, The ball milling method is wet ball milling.

5. The preparation method according to claim 3, characterized in that, The mass ratio of material to grinding balls in the ball mill is 1:(7-8).

6. The preparation method according to claim 3, characterized in that, The ball milling time is 30-50 minutes.

7. The preparation method according to claim 3, characterized in that, The preheating temperature is 700-800℃.

8. The preparation method according to claim 3, characterized in that, The preheating time is 2-3 hours.

9. The preparation method according to claim 3, characterized in that, The grinding method is wet grinding.

10. The preparation method according to claim 3, characterized in that, The grinding time is 70-90 minutes.

11. The preparation method according to claim 3, characterized in that, The heat treatment temperature is 700-850℃.

12. The preparation method according to claim 3, characterized in that, The heat treatment time is 3-3.5 hours.

13. The preparation method according to claim 3, characterized in that, The adhesive includes polyvinyl alcohol.

14. The preparation method according to claim 3, characterized in that, The amount of adhesive added is 8-10% of the mass of the ferrite mixture.

15. The preparation method according to claim 3, characterized in that, The mixed atmosphere comprises a protective gas and oxygen, with the oxygen content being 3-21% by volume.

16. The preparation method according to claim 15, characterized in that, The protective gas includes one or a combination of at least two of nitrogen, helium, neon, or argon.

17. The preparation method according to claim 3, characterized in that, The first sintering is carried out at 1280-1350℃ for 4-10 hours in a mixed atmosphere with an oxygen volume percentage of 3-8%.

18. The preparation method according to claim 3, characterized in that, The second sintering is carried out at 600-700℃ for 1-3 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%.

19. The preparation method according to claim 3, characterized in that, The third sintering is carried out at 1000-1100℃ for 4-8 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%.

20. The preparation method according to claim 3, characterized in that, The preparation method includes: Prepare the main ingredients and auxiliary ingredients according to the formula; The main component material is sequentially ball-milled, dried and pre-calcined, then mixed with auxiliary component material, sand-milled and dried to obtain ferrite mixture; The obtained ferrite mixture was subjected to heat treatment in sequence, then mixed with binder and granulated to obtain ferrite granules. After sintering in a mixed atmosphere and cooling, manganese zinc ferrite material was obtained. The ball milling method is wet ball milling; the mass ratio of material to grinding balls in the ball milling is 1:(7-8); the ball milling time is 30-50 min; the pre-firing temperature is 700-800℃; the pre-firing time is 2-3 h; the sand milling method is wet sand milling; the sand milling time is 70-90 min; the heat treatment temperature is 700-850℃; the heat treatment time is 3-3.5 h; the binder includes polyvinyl alcohol; the amount of binder added is 8-10% of the mass of the ferrite mixture; the mixing atmosphere includes a protective gas and oxygen, with the oxygen volume percentage being 3-21%; the protective gas includes one or a combination of at least two of nitrogen, helium, neon, or argon. The sintering includes a second sintering, a third sintering, and a first sintering performed sequentially. The second sintering is performed at 600-700℃ for 1-3 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%; the third sintering is performed at 1000-1100℃ for 4-8 hours in a mixed atmosphere with an oxygen volume percentage of 19-21%; the first sintering is performed at 1280-1350℃ for 4-10 hours in a mixed atmosphere with an oxygen volume percentage of 3-8%.

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