Wide-temperature low-loss manganese zinc ferrite material as well as preparation method and application thereof

Abstract

The invention relates to a wide-temperature low-loss manganese zinc ferrite material and a preparation method and application thereof.The wide-temperature low-loss manganese zinc ferrite material comprises main components and additives, the main components comprise Fe2O3, ZnO and Mn3O4, and the additives comprise CaCO3, SiO2, TiO2 and Co2O3; and in the main components, the mass ratio of Fe2O3 is 69.7 wt%-70 wt%, the mass ratio of ZnO is 6 wt%-7.5 wt%, and the balance is Mn3O4 in percentage by mass. The specific resistance of the manganese-zinc ferrite material is effectively improved by adjusting the content of the main components, regulating and controlling the additive and the addition amount of the additive and optimizing the sintering process, so that the overall loss in the frequency range of about 300kHz is relatively low, and the energy conversion efficiency of operation at the frequency is remarkably improved.

Description

A wide-temperature, low-loss manganese-zinc ferrite material, its preparation method and application Technical Field

[0001] This disclosure relates to the field of preparation technology of manganese-zinc ferrite materials, and in particular to a wide-temperature, low-loss manganese-zinc ferrite material, its preparation method, and its application. Background Technology

[0002] Manganese-zinc ferrite, as a soft magnetic material, occupies an important position in the electronics industry. Due to its high permeability, high resistivity, and low loss characteristics, it is widely used in components such as transformers, inductors, and filters. With the development of digital technology and fiber optic communication technology in the information industry, ordinary magnetic cores are increasingly unable to meet customer needs, making high-performance manganese-zinc ferrite cores a growing market trend.

[0003] As high-end servers become more widespread, the application requirements for magnetic cores have also become more stringent, gradually moving from 100kHz to 300kHz or even higher. Compared to 100kHz applications, 300kHz places higher demands on the eddy current losses of the magnetic core, and increasing resistivity is an effective way to reduce eddy current losses in the magnetic core.

[0004] CN118271076A discloses a high-resistivity, wide-temperature, low-loss MnZn ferrite, its preparation method, and its applications. The main components of the ferrite include Fe2O3: 52.8~53.8 mol%, MnO: 37.2~38.2 mol%, and ZnO as the balance; the additives include CaCO3: 0.2~0.4 wt%, ZrO2: 0.03~0.06 wt%, HfO2: 0.05~0.07 wt%, TiO2: 0.1~0.3 wt%, and Bi2O3: 0.04~0.07 wt%, with a resistivity of approximately 12~14 Ω·m. CN108530050A discloses a wide-temperature, low-loss, high-impedance MnZn soft magnetic... The ferrite material and its preparation method are disclosed. The main components of the ferrite include Fe₂O₃: 52-55 mol%, ZnO: 9.5-12.5 mol%, and MnO as the balance. The auxiliary materials include CaO: 0.03-0.05 wt%. Additives include CaCO₃: 0.03-0.05 wt%, nano-BaTiO₃: 0.05-0.08 wt%, Bi₂O₃: 0.001-0.05 wt%, CaO: 0.001-0.035 wt%, Nb₂O₅: 0.001-0.02 wt%, HfO₂: 0.003-0.20 wt%, and Co₂O₃: 0.08-0.30 wt%, with a resistivity of approximately ≥30 Ω·m. The MnZn soft magnetic ferrite materials disclosed in the prior art are mainly suitable for applications under 100 kHz 200 mT conditions; the overall loss at relatively high frequencies of 300 kHz is not addressed.

[0005] Therefore, given the high requirements for magnetic cores, providing a wide-temperature, low-loss manganese-zinc ferrite material suitable for the frequency range of around 300kHz is a technical problem that urgently needs to be solved. Summary of the Invention

[0006] To address the aforementioned technical problems, this disclosure provides a wide-temperature, low-loss manganese-zinc ferrite material, its preparation method, and its applications. By adjusting the content of the main component and optimizing the additives and sintering process, this disclosure effectively improves the resistivity of the manganese-zinc ferrite material, resulting in lower overall losses in the frequency range of approximately 300 kHz. This significantly improves the energy conversion efficiency at this frequency. The resulting manganese-zinc ferrite material exhibits a power consumption ≤223 kW / m² at 25℃ within a wide temperature range of 25℃ to 140℃, under conditions of 300 kHz and 100 mT. 3 Power consumption at 100℃ ≤ 206kW / m 3 Power consumption at 140℃ ≤322kW / m 3 .

[0007] To achieve this objective, the present disclosure adopts the following technical solution: Firstly, the present disclosure provides a wide-temperature, low-loss manganese-zinc ferrite material, comprising a main component and additives. The main component includes Fe2O3, ZnO, and Mn3O4, and the additives include CaCO3, SiO2, TiO2, and Co2O3. In the main component, the mass percentage of Fe2O3 is 69.7wt%~70wt%, for example, 69.7wt%, 69.72wt%, 69.75wt%, 69.78wt%, 69.8wt%, 69... The ZnO content is 6 wt% to 7.5 wt%, for example, 6 wt%, 6.1 wt%, 6.2 wt%, 6.3 wt%, 6.4 wt%, 6.5 wt%, 6.6 wt%, 6.7 wt%, 6.8 wt%, 6.9 wt%, 7 wt%, 7.1 wt%, 7.2 wt%, 7.3 wt%, 7.4 wt%, or 7.5 wt%, with the balance being Mn3O4.

[0008] This disclosure improves the resistivity of manganese-zinc ferrite materials by controlling the mass percentage of Fe2O3 in the main component to 69.7wt%~70wt%, ZnO to 6wt%~7.5wt%, with the balance being Mn3O4, and by adding additives. This results in a reduction of overall losses in the frequency range of approximately 300kHz, thereby improving the energy conversion efficiency at this frequency. Specifically, the addition of CaCO3 and SiO2 in the additives works together to precipitate CaSiO3 at the grain boundaries, forming a high-resistivity layer to increase the grain boundary resistivity and reduce eddy current losses. The addition of TiO2, on the one hand, during the sintering process, increases the resistivity of the TiO2 content. 4＋ Ions dissolve into the ferrite lattice, typically occupying octahedral (B-site) positions. Ti 4＋ The introduction of Ti alters grain boundary mobility, suppresses abnormal grain growth, refines grains, and thus reduces eddy current losses. On the other hand, Ti... 4＋ Ion replacement of Fe 3＋ Ions alter the distribution of cations, causing K1 (magnetocrystalline anisotropy constant) to approach 0, thus reducing hysteresis loss. Fe 3＋ Ions and Fe 2＋ Ions interconvert through the absorption and release of electrons; therefore, the addition of Co2O3 and Fe... 2＋ It forms a synergistic effect. Because it has a positive K1, it compensates for the negative K1 value of manganese zinc ferrite, which tends to 0, reducing hysteresis loss and thus achieving the effect of reducing loss under wide temperature conditions.

[0009] As a preferred technical solution of this disclosure, based on the total mass of the main component, the content of CaCO3 is 1200ppm~2000ppm, such as 1200ppm, 1300ppm, 1400ppm, 1500ppm, 1600ppm, 1700ppm, 1800ppm, 1900ppm or 2000ppm.

[0010] Preferably, based on the total mass of the main components, the SiO2 content is 50ppm to 200ppm, for example, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, 100ppm, 110ppm, 120ppm, 130ppm, 140ppm, 150ppm, 160ppm, 170ppm, 180ppm, 190ppm, or 200ppm.

[0011] Preferably, the TiO2 content is 1000ppm~2000ppm based on the total mass of the main component, for example, 1000ppm, 1100ppm, 1200ppm, 1300ppm, 1400ppm, 1500ppm, 1600ppm, 1700ppm, 1800ppm, 1900ppm or 2000ppm.

[0012] Preferably, based on the total mass of the main components, the content of Co2O3 is 3000ppm to 4000ppm, such as 3000ppm, 3100ppm, 3200ppm, 3300ppm, 3400ppm, 3500ppm, 3600ppm, 3700ppm, 3800ppm, 3900ppm, or 4000ppm.

[0013] Secondly, this disclosure also provides a method for preparing a wide-temperature, low-loss manganese-zinc ferrite material as described in the first aspect. The preparation method includes the following steps: S1, mixing the main components in a first mixing process and pre-calcining them to obtain a pre-calcined material; S2, mixing the additives and the pre-calcined material obtained in step S1 in a second mixing process to obtain an intermediate powder, which is then granulated and sintered to obtain the wide-temperature, low-loss manganese-zinc ferrite material; the main components include Fe2O3, ZnO, and Mn3O4, and the additives include CaCO3, SiO2, TiO2, and Co2O3; in the main components, by mass percentage, Fe2O3 accounts for 69.7wt%~70wt%, ZnO accounts for 6wt%~7.5wt%, and the balance is Mn3O4.

[0014] This disclosure, while adjusting the content of the main components and supplementing with additives, further optimizes the sintering process, further improves the resistivity of the manganese-zinc ferrite material, and further reduces the overall loss in the frequency range of about 300kHz, significantly improving the energy conversion efficiency at this frequency.

[0015] As a preferred technical solution of this disclosure, the sintering in step S2 includes an initial heating section, a densification heating section, a holding section, and a cooling section.

[0016] As a preferred technical solution of this disclosure, the initial heating stage heats the temperature to T1, where T1 is 600℃~900℃, such as 600℃, 650℃, 700℃, 750℃, 800℃, 850℃ or 900℃.

[0017] Preferably, the heating rate of the initial heating section is 0.1℃ / min to 5℃ / min, for example, 0.1℃ / min, 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min.

[0018] Preferably, the sintering atmosphere in the initial heating section is an air atmosphere.

[0019] As a preferred technical solution of this disclosure, the dense heating section heats the temperature from T1 to the holding temperature T2.

[0020] Preferably, the heating rate of the dense heating section is 0.1℃ / min to 5℃ / min, for example, 0.1℃ / min, 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min.

[0021] Preferably, the sintering atmosphere in the dense heating section is an oxygen-containing atmosphere.

[0022] Preferably, the oxygen content in the oxygen-containing atmosphere used in the dense heating section is 1 vol% to 5 vol%, for example, 1 vol%, 2 vol%, 3 vol%, 4 vol%, or 5 vol%.

[0023] The sintering atmosphere of the densification heating section disclosed herein is an oxygen-containing atmosphere, and the oxygen content is controlled at 1 vol% to 5 vol%. It adopts a low-oxygen sintering method throughout the process (oxygen content is maintained at 1 vol% to 5 vol%). Compared with the traditional sintering process, which uses vacuum sintering (reaction atmosphere is nitrogen atmosphere) from around 700℃ to the highest temperature, low-oxygen sintering can slow down the densification process of the material, slow down the grain growth, and play a role in refining the grains, thereby reducing eddy current loss. In addition, the oxygen content in the densification heating section is maintained at 1 vol% to 5 vol%. If the oxygen content is too high or air is used directly, the porosity will increase, and the effect of reducing power consumption cannot be achieved.

[0024] Preferably, the oxygen-containing atmosphere used in the dense heating section includes a nitrogen-oxygen mixture or a nitrogen-air mixture.

[0025] As a preferred technical solution of this disclosure, the insulation temperature T2 of the insulation section is 1220℃~1270℃, such as 1220℃, 1230℃, 1240℃, 1250℃, 1260℃ or 1270℃.

[0026] Preferably, the heat preservation time of the heat preservation section is 360min~600min, for example 360min, 400min, 450min, 500min, 550min or 600min.

[0027] Preferably, the sintering atmosphere of the heat preservation section is an oxygen-containing atmosphere.

[0028] Preferably, the oxygen content in the oxygen-containing atmosphere used in the heat preservation section is 2 vol% to 4 vol%, for example, 2 vol%, 2.5 vol%, 3 vol%, 3.5 vol%, or 4 vol%.

[0029] Preferably, the oxygen-containing atmosphere in the insulation section uses a nitrogen-oxygen mixture or a nitrogen-air mixture.

[0030] Preferably, the cooling section is a balanced oxygen partial pressure sintering process.

[0031] As a preferred technical solution of this disclosure, step S1, the first mixing, and step S2, the second mixing, each independently include sand milling.

[0032] Preferably, the first mixture in step S1 further includes a solvent.

[0033] Preferably, the mixing time in step S1 is 1h to 2h, for example, 1h, 1.5h or 2h.

[0034] Preferably, after the first mixing is completed in step S1, a drying process is further included.

[0035] Preferably, the preheating temperature in step S1 is 750℃~850℃, such as 750℃, 760℃, 770℃, 780℃, 790℃, 800℃, 810℃, 820℃, 830℃, 840℃ or 850℃.

[0036] Preferably, the heat preservation time for preheating in step S1 is 2h to 4h, such as 2h, 2.5h, 3h, 3.5h or 4h.

[0037] Preferably, the sintering atmosphere for pre-firing in step S1 is an air atmosphere.

[0038] As a preferred technical solution of this disclosure, the second mixed material in step S2 further includes a solvent.

[0039] Preferably, the mixing time in step S2 is 2h to 4h, for example, 2h, 2.5h, 3h, 3.5h or 4h.

[0040] Preferably, after the second mixing is completed in step S2, a drying process is further included to obtain an intermediate powder.

[0041] Preferably, the median particle size D50 of the intermediate powder in step S2 is 0.9μm to 1.2μm, such as 0.9μm, 1μm, 1.1μm or 1.2μm.

[0042] Preferably, the granulating agent used in step S2 includes polyvinyl alcohol (PVA) and / or polyvinyl butyral (PVB).

[0043] Preferably, the amount of granulating agent added is 5wt% to 10wt% of the mass of the intermediate powder, such as 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, or 10wt%.

[0044] Thirdly, this disclosure also provides an application of a wide-temperature, low-loss manganese-zinc ferrite material, wherein the wide-temperature, low-loss manganese-zinc ferrite material as described in the first aspect, or the wide-temperature, low-loss manganese-zinc ferrite material prepared by the preparation method described in the second aspect, is applied to electronic components.

[0045] Compared with the prior art, this disclosure has at least the following beneficial effects: 1) By adjusting the content of the main component and supplementing it with additives and optimizing the sintering process, this disclosure effectively improves the resistivity of manganese-zinc ferrite materials, thereby resulting in lower overall losses in the frequency range of about 300kHz, significantly improving the energy conversion efficiency at this frequency. The resulting manganese-zinc ferrite material has a power consumption of ≤223kW / m at 25℃ under the conditions of 300kHz and 100mT in a wide temperature range of 25℃~140℃. 3 Power consumption at 100℃ ≤ 206kW / m 3 Power consumption at 140℃ ≤322kW / m 3 .

[0046] 2) The sintering process disclosed herein includes an initial heating section, a dense heating section, a holding section, and a cooling section. In the dense heating section, a low-oxygen sintering method is adopted, which can slow down grain growth, refine grains, thereby reducing eddy current loss, and also reduce porosity, further reducing power consumption. Detailed Implementation

[0047] To facilitate understanding of this disclosure, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of this disclosure.

[0048] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0049] Example 1 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The main components of the wide-temperature, low-loss manganese-zinc ferrite material are 69.85 wt% Fe2O3, 7.0 wt% ZnO and the balance Mn3O4. Based on the total mass of the main components, the additives are 1600 ppm CaCO3, 100 ppm SiO2, 1500 ppm TiO2 and 3500 ppm Co2O3.

[0050] The preparation method includes the following steps: S1, Weigh the main components according to the formula: Fe2O3, ZnO and Mn3O4 (the total mass percentage of the main components is 100wt%), and weigh the additives: 1600ppm CaCO3, 100ppm SiO2, 1500ppm TiO2 and 3500ppm Co2O3 (all based on the total mass of the main components); Grind the main components Fe2O3, ZnO and Mn3O4, and deionized water for 1 hour, during which the mass ratio of the above materials, grinding balls and deionized water is 1:6:1.5. After drying, pre-calcine at 800℃ for 3 hours in an air atmosphere to obtain pre-calcined material; S2, Combine the additives CaCO3, SiO2, TiO2 and Co2O3 with the material from step S1. The pre-calcined material was milled with deionized water for 3 hours. During the process, the mass ratio of the above materials, grinding balls and deionized water was 1:6:1.5. After drying, an intermediate powder with a median particle size D50 of 1 μm was obtained. 8 wt% of PVA was added to the intermediate powder for granulation and molding, followed by sintering. The sintering process included first heating to 800℃ in air at a heating rate of 2.5℃ / min, which was the initial heating stage. Then, the temperature was increased from 800℃ to 1250℃ in a nitrogen-oxygen mixture (oxygen content of 3 vol%) at a heating rate of 2.5℃ / min, which was the densification heating stage. Finally, the temperature was held at 1250℃ for 480 min in a nitrogen-oxygen mixture (oxygen content of 3 vol%). The cooling stage met the equilibrium oxygen partial pressure sintering requirements, resulting in a wide-temperature, low-loss manganese-zinc ferrite material.

[0051] Example 2 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The main components of the wide-temperature, low-loss manganese-zinc ferrite material are 70 wt% Fe2O3, 6.0 wt% ZnO and the balance Mn3O4. Based on the total mass of the main components, the additives are 2000 ppm CaCO3, 200 ppm SiO2, 1000 ppm TiO2 and 3000 ppm Co2O3.

[0052] The preparation method includes the following steps: S1, Weigh the main components according to the formula: Fe2O3, ZnO and Mn3O4 (the total mass percentage of the main components is 100wt%), and weigh the additives: 2000ppm CaCO3, 200ppm SiO2, 1000ppm TiO2 and 3000ppm Co2O3 (all based on the total mass of the main components); Grind the main components Fe2O3, ZnO and Mn3O4, and deionized water for 2 hours, during which the mass ratio of the above materials, grinding balls and deionized water is 1:5:2. After drying, pre-calcine at 750℃ for 4 hours in an air atmosphere to obtain pre-calcined material; S2, Combine the additives CaCO3, SiO2, TiO2 and Co2O3 with the material from step S1. The pre-calcined material was milled with deionized water for 4 hours. During the process, the mass ratio of the above materials, grinding balls and deionized water was 1:5:2. After drying, an intermediate powder with a median particle size D50 of 0.9 μm was obtained. 5 wt% PVA was added to the intermediate powder for granulation and molding, followed by sintering. The sintering process included first heating to 900℃ in air at a heating rate of 2.5℃ / min, which is the initial heating stage. Then, the temperature was increased from 900℃ to 1270℃ in a nitrogen-oxygen mixture (oxygen content of 1 vol%) at a heating rate of 5℃ / min, which is the densification heating stage. Then, the temperature was held at 1270℃ for 600 min in a nitrogen-oxygen mixture (oxygen content of 4 vol%). The cooling stage met the equilibrium oxygen partial pressure sintering requirements, resulting in a wide-temperature, low-loss manganese-zinc ferrite material.

[0053] Example 3 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The main components of the wide-temperature, low-loss manganese-zinc ferrite material are 69.7 wt% Fe2O3, 7.5 wt% ZnO and the balance Mn3O4. Based on the total mass of the main components, the additives are 1200 ppm CaCO3, 50 ppm SiO2, 2000 ppm TiO2 and 4000 ppm Co2O3.

[0054] The preparation method includes the following steps: S1, weighing the main components according to the formula: Fe2O3, ZnO and Mn3O4 (the total mass percentage of the main components is 100wt%), and weighing the additives: 1200ppm CaCO3, 50ppm SiO2, 2000ppm TiO2 and 4000ppm Co2O3 (all based on the total mass of the main components); grinding the main components Fe2O3, ZnO and Mn3O4 with deionized water for 2 hours, during which the mass ratio of the above materials, grinding balls and deionized water is 1:7:1, drying and pre-calcining at 850℃ for 2 hours in air atmosphere to obtain pre-calcined material; S2, pre-calcining the additives CaCO3, SiO2, TiO2 and Co2O3 with the material from step S1. The material was milled with deionized water for 2 hours. During the process, the mass ratio of the above material, milling balls and deionized water was 1:7:1. After drying, an intermediate powder with a median particle size D50 of 1.2 μm was obtained. 10 wt% of PVA was added to the intermediate powder for granulation and molding, followed by sintering. The sintering process included first heating to 600℃ in air at a heating rate of 2.5℃ / min, which is the initial heating section. Then, the temperature was increased from 600℃ to 1220℃ in a nitrogen-oxygen mixture (oxygen content of 5 vol%) at a heating rate of 0.1℃ / min, which is the densification heating section. Then, the temperature was held at 1220℃ for 360 min in a nitrogen-oxygen mixture (oxygen content of 2 vol%). The cooling section met the equilibrium oxygen partial pressure sintering, resulting in a wide-temperature, low-loss manganese-zinc ferrite material.

[0055] Example 4 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The composition and content of the wide-temperature, low-loss manganese-zinc ferrite material are consistent with those in Example 1.

[0056] The difference between the preparation method and Example 1 is that in step S2, a dense heating section is carried out under nitrogen (oxygen content of 0 vol%), while the rest of the preparation methods and parameters are consistent with Example 1.

[0057] Example 5 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The composition and content of the wide-temperature, low-loss manganese-zinc ferrite material are consistent with those in Example 1.

[0058] The difference between the preparation method and Example 1 is that in step S2, a dense heating section is carried out under a nitrogen-oxygen mixture (oxygen content of 6 vol%), while the rest of the preparation methods and parameters are consistent with Example 1.

[0059] Example 6 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The composition and content of the wide-temperature, low-loss manganese-zinc ferrite material are consistent with those of Example 1.

[0060] The difference between the preparation method and Example 1 is that in step S2, the densification heating section includes: heating from 800°C to 1100°C under nitrogen (oxygen content of 0 vol%), and then replacing it with heating from 1100°C to 1250°C under a nitrogen-oxygen mixture (oxygen content of 3 vol%). The remaining preparation methods and parameters are consistent with those of Example 1.

[0061] Example 7 This example provides a wide-temperature, low-loss manganese-zinc ferrite material and its preparation method. The composition and content of the wide-temperature, low-loss manganese-zinc ferrite material are consistent with those in Example 1.

[0062] The difference between the preparation method and Example 1 is that in step S2, the densification heating section includes: heating from 800°C to 1100°C in a nitrogen-oxygen mixture (oxygen content of 6 vol%), and then replacing it with heating from 1100°C to 1250°C in a nitrogen-oxygen mixture (oxygen content of 3 vol%). The remaining preparation methods and parameters are consistent with those of Example 1.

[0063] Comparative Example 1 This comparative example provides a manganese-zinc ferrite material and its preparation method. The difference between the manganese-zinc ferrite material and Example 1 is that the mass of Fe2O3 is 69.6wt%, the mass of ZnO is 7.6wt%, and the balance is Mn3O4. The remaining composition and content are the same as those in Example 1.

[0064] The difference between the preparation method described herein and Example 1 is that the formula is adjusted accordingly, while the remaining preparation methods and parameters remain the same as in Example 1.

[0065] Comparative Example 2 provides a manganese-zinc ferrite material and its preparation method. The difference between the manganese-zinc ferrite material and Example 1 is that the mass of Fe2O3 is 70.15wt%, the mass of ZnO is 5.8wt%, and the balance is Mn3O4. The remaining composition and content are the same as those in Example 1.

[0066] The difference between the preparation method described herein and Example 1 is that the formula is adjusted accordingly, while the remaining preparation methods and parameters remain the same as in Example 1.

[0067] Comparative Example 3 provides a manganese-zinc ferrite material and its preparation method. The difference between the manganese-zinc ferrite material and Example 1 is that CaCO3 is omitted, and the additives are 100 ppm SiO2, 1500 ppm TiO2 and 3500 ppm Co2O3. The remaining composition and content are the same as in Example 1.

[0068] The difference between the preparation method described herein and Example 1 is that the formula is adjusted accordingly, while the remaining preparation methods and parameters remain the same as in Example 1.

[0069] Comparative Example 4 provides a manganese-zinc ferrite material and its preparation method. The difference between the manganese-zinc ferrite material and Example 1 is that SiO2 is omitted, and the additives are 1600 ppm CaCO3, 1500 ppm TiO2 and 3500 ppm Co2O3. The remaining composition and content are the same as in Example 1.

[0070] The difference between the preparation method described herein and Example 1 is that the formula is adjusted accordingly, while the remaining preparation methods and parameters remain the same as in Example 1.

[0071] Comparative Example 5 provides a manganese-zinc ferrite material and its preparation method. The difference between the manganese-zinc ferrite material and Example 1 is that Co2O3 is omitted, and the additives are 1600ppm CaCO3, 100ppm SiO2 and 1500ppm TiO2. The remaining composition and content are the same as in Example 1.

[0072] The difference between the preparation method described herein and Example 1 is that the formula is adjusted accordingly, while the remaining preparation methods and parameters remain the same as in Example 1.

[0073] Comparative Example 6 provides a manganese-zinc ferrite material and its preparation method. The difference between the manganese-zinc ferrite material and Example 1 is that TiO2 is omitted, and the additives are 1600 ppm CaCO3, 100 ppm SiO2 and 3500 ppm Co2O3. The remaining composition and content are the same as in Example 1.

[0074] The difference between the preparation method described herein and Example 1 is that the formula is adjusted accordingly, while the remaining preparation methods and parameters remain the same as in Example 1.

[0075] The wide-temperature, low-loss manganese-zinc ferrite materials obtained in Examples 1-7 and Comparative Examples 1-6 were placed on the SY8219 testing equipment, and the loss of the standard ring (25×15×8mm) was tested under the conditions of 300kHz 100mT, T=25℃, 100℃ and 140℃ respectively. The results are shown in Table 1.

[0076] The resistance R of the wide-temperature, low-loss manganese-zinc ferrite materials obtained in Examples 1-7 and Comparative Examples 1-6 was tested using a Keysight E4991A impedance analyzer at 40Hz, 0.25V, and T=25℃ (material size 4×4×40mm). The resistivity was calculated according to the formula ρ=RS / l, and the results are shown in Table 1.

[0077] Table 1 The test results show that: (1) As can be seen from Examples 1 to 3, this disclosure effectively improves the resistivity of manganese-zinc ferrite material by adjusting the content of the main component and supplementing it with additives and optimizing the sintering process, thereby making the overall loss in the frequency range of about 300kHz lower and significantly improving the energy conversion efficiency at this frequency. The resulting manganese-zinc ferrite material has a power consumption of ≤223kW / m at 25℃ under the conditions of 300kHz and 100mT in a wide temperature range of 25℃ to 140℃. 3 Power consumption at 100℃ ≤ 206kW / m 3 Power consumption at 140℃ ≤322kW / m 3 .

[0078] (2) As can be seen from Examples 1 and 4 to 7, this disclosure further controls the sintering atmosphere of the densification heating section to be an oxygen-containing atmosphere, and controls the oxygen content to be 1 vol% to 5 vol%. It adopts a low-oxygen sintering method throughout the process (oxygen content is maintained at 1 vol% to 5 vol%). Compared with the traditional sintering process, which uses vacuum sintering (reaction atmosphere is nitrogen atmosphere) from about 700°C to the highest temperature, low-oxygen sintering can slow down the densification process of the material, slow down the growth of grains, and play a role in refining grains, thereby reducing eddy current loss. In addition, the oxygen content of the densification heating section is maintained at 1 vol% to 5 vol%. If the oxygen content is too high or air is used directly, the porosity will increase and the effect of reducing power consumption cannot be achieved.

[0079] (3) As can be seen from Example 1 and Comparative Examples 1 to 6, this disclosure can further improve the resistivity of manganese zinc ferrite material by adjusting the mass ratio of Fe2O3 in the main component to 69.7wt%~70wt%, the mass ratio of ZnO to 6wt%~7.5wt%, and the balance to Mn3O4, and by adding additives including CaCO3, SiO2, TiO2 and Co2O3. This can reduce the overall loss in the frequency range of about 300kHz and improve the energy conversion efficiency at this frequency. If the mass ratio of Fe2O3 and the mass ratio of ZnO in the main component are too high or too low, or if the selection of additives is omitted, it is impossible to achieve the overall loss reduction of manganese zinc ferrite material in the wide temperature range of 25℃~140℃ under the conditions of 300kHz and 100mT.

[0080] In summary, this disclosure effectively improves the resistivity of manganese-zinc ferrite materials by adjusting the content of the main components and supplementing them with additives and optimizing the sintering process. This results in lower overall losses in the frequency range of approximately 300 kHz, significantly improving the energy conversion efficiency at this frequency. The resulting manganese-zinc ferrite material exhibits a power consumption of ≤223 kW / m at 25℃ within a wide temperature range of 25℃ to 140℃ at 300 kHz and 100 mT.3 Power consumption at 100℃ ≤ 206kW / m 3 Power consumption at 140℃ ≤322kW / m 3 .

[0081] The applicant declares that the above description is only a specific implementation of this disclosure, but the protection scope of this disclosure is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this disclosure fall within the protection and disclosure scope of this disclosure.

Claims

1. A wide-temperature, low-loss manganese-zinc ferrite material, characterized in that, The wide-temperature, low-loss manganese-zinc ferrite material comprises a main component and additives. The main component includes Fe2O3, ZnO, and Mn3O4, and the additives include CaCO3, SiO2, TiO2, and Co2O3. In the main component, by mass percentage, Fe2O3 accounts for 69.7wt%~70wt%, ZnO accounts for 6wt%~7.5wt%, and the balance is Mn3O4.

2. The wide-temperature, low-loss manganese-zinc ferrite material according to claim 1, characterized in that, Based on the total mass of the main components, the content of CaCO3 is 1200ppm~2000ppm; preferably, based on the total mass of the main components, the content of SiO2 is 50ppm~200ppm; preferably, based on the total mass of the main components, the content of TiO2 is 1000ppm~2000ppm; preferably, based on the total mass of the main components, the content of Co2O3 is 3000ppm~4000ppm.

3. A method for preparing a wide-temperature, low-loss manganese-zinc ferrite material as described in claim 1 or 2, characterized in that, The preparation method includes the following steps: S1, mixing the main components in a first mixing process, followed by pre-calcination to obtain a pre-calcined material; S2, mixing the additives and the pre-calcined material obtained in step S1 in a second mixing process to obtain an intermediate powder, followed by granulation and sintering to obtain a wide-temperature, low-loss manganese-zinc ferrite material; the main components include Fe2O3, ZnO and Mn3O4, and the additives include CaCO3, SiO2, TiO2 and Co2O3; in the main components, by mass percentage, Fe2O3 accounts for 69.7wt%~70wt%, ZnO accounts for 6wt%~7.5wt%, and the balance is Mn3O4.

4. The preparation method according to claim 3, characterized in that, The sintering process in step S2 includes an initial heating section, a densification heating section, a holding section, and a cooling section.

5. The preparation method according to claim 4, characterized in that, The initial heating stage raises the temperature to T1, where T1 is 600℃~900℃.

6. The preparation method according to claim 4, characterized in that, The densification heating section heats the temperature from T1 to the holding temperature T2; preferably, the heating rate of the densification heating section is 0.1℃ / min to 5℃ / min; preferably, the sintering atmosphere of the densification heating section is an oxygen-containing atmosphere; preferably, the oxygen content in the oxygen-containing atmosphere used in the densification heating section is 1 vol% to 5 vol%; preferably, the gas used in the oxygen-containing atmosphere of the densification heating section includes a nitrogen-oxygen mixture or a nitrogen-air mixture.

7. The preparation method according to claim 4, characterized in that, The heat preservation temperature T2 of the heat preservation section is 1220℃~1270℃; preferably, the heat preservation time of the heat preservation section is 360min~600min; preferably, the sintering atmosphere of the heat preservation section is an oxygen-containing atmosphere; preferably, the oxygen content in the oxygen-containing atmosphere used in the heat preservation section is 2vol%~4vol%; preferably, the gas used in the oxygen-containing atmosphere of the heat preservation section includes a nitrogen-oxygen mixture or a nitrogen-air mixture; preferably, the cooling section is a balanced oxygen partial pressure sintering.

8. The preparation method according to claim 3, characterized in that, Step S1, the first mixing, and step S2, the second mixing, each independently include sand milling; preferably, the time for the first mixing in step S1 is 1h to 2h; preferably, the holding temperature for pre-firing in step S1 is 750℃ to 850℃; preferably, the holding time for pre-firing in step S1 is 2h to 4h; preferably, the sintering atmosphere for pre-firing in step S1 is an air atmosphere.

9. The preparation method according to claim 3, characterized in that, The mixing time in step S2 is 2h~4h; preferably, after the second mixing in step S2 is completed, a drying process is further included to obtain intermediate powder; preferably, the median particle size D50 of the intermediate powder in step S2 is 0.9μm~1.2μm; preferably, the granulating agent used in step S2 includes polyvinyl alcohol and / or polyvinyl butyral; preferably, the amount of granulating agent added is 5wt%~10wt% of the mass of the intermediate powder.

10. An application of a wide-temperature, low-loss manganese-zinc ferrite material, characterized in that, The wide-temperature, low-loss manganese-zinc ferrite material as described in claim 1 or 2, or the wide-temperature, low-loss manganese-zinc ferrite material prepared by the preparation method as described in any one of claims 3 to 9, is applied to electronic components.

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