Iron-poor manganese zinc ferrite material with high magnetic conductivity and high Curie temperature and preparation method thereof

Abstract

The invention discloses a high-permeability and high-Curie-temperature iron-poor manganese zinc ferrite material and a preparation method thereof, and belongs to the field of soft magnetic ferrites. Comprising a main material and an auxiliary material, the main material is composed of an iron compound, a zinc compound, a cobalt compound and a manganese compound, the iron compound accounts for 46-50 mol% in terms of Fe2O3 conversion amount, the zinc compound accounts for 12-16 mol% in terms of ZnO conversion amount, the cobalt compound accounts for 1-3 mol% in terms of Co2O3 conversion amount, and the manganese compound accounts for the balance in terms of MnO conversion amount; the auxiliary material is prepared from the following components: TiO2, CaCO3, V2O5, SiO2 and Nb2O5. The method aims at obtaining the initial magnetic conductivity gt; 3000, Curie temperature gt; and the iron-poor manganese zinc ferrite material can be obtained at 180 DEG C.

Description

Technical Field

[0001] The invention belongs to the field of soft magnetic ferrites, and more specifically, relates to a low-iron manganese-zinc ferrite material with high magnetic permeability and high Curie temperature and a preparation method thereof. Background Art

[0002] With the development of Internet of Things technology, there are more and more electromagnetic interference (EMI) in the space we live in. To eliminate these electromagnetic interferences, electromagnetic compatibility (EMC) design is needed, which requires anti-EMI materials. Usually, manganese-zinc ferrite (iron-rich) materials are used in the frequency band <10MHZ, and nickel-zinc ferrite materials are used in the frequency band >10MHZ. In order to reduce costs, iron-poor manganese-zinc ferrite materials that can be used in the frequency band >10MHZ have made certain progress and replaced some of the application areas of nickel-zinc ferrite. Manganese-zinc ferrite has a larger saturation magnetization intensity than nickel-zinc ferrite, and its magnetocrystalline anisotropy, magnetostriction, grain size and defects are small. Therefore, the low-frequency magnetic permeability of manganese-zinc ferrite is significantly higher than that of nickel-zinc ferrite; similarly, the low-frequency impedance of manganese-zinc ferrite is also significantly higher than that of nickel-zinc ferrite. However, due to the Fe in iron-rich manganese-zinc ferrite, the 2+ More, Fe 2+ with Fe 3+ The electron transition between the two makes the resistivity drop sharply and the dielectric constant increase. Dispersion occurs in the lower frequency band, which makes the cutoff frequency of the iron-rich manganese-zinc ferrite low. The high-frequency and high-impedance materials adopt the iron-deficient formula. The Fe in the spinel structure 2+ Very few, and the sintering process of poor iron manganese zinc ferrite is simpler than that of rich iron manganese zinc ferrite, which makes poor iron manganese zinc ferrite have high resistivity, small eddy current loss, and high magnetic permeability in the high frequency band, so the poor iron manganese zinc ferrite sample still has high impedance in the high frequency band. The poor iron manganese zinc ferrite sample combines the low-frequency high impedance characteristics of rich iron manganese zinc ferrite and the high-frequency high impedance characteristics of nickel zinc ferrite.

[0003] The reported initial magnetic permeability of the iron-poor manganese-zinc ferrite material is as high as 4000, but the Curie temperature does not exceed 130°C at high magnetic permeability. The invention application with publication number CN111892395A provides an iron-poor high-impedance manganese-zinc ferrite material, whose magnetic permeability is 3000, but its Curie temperature is only 140°C, and the saturation magnetic induction intensity is low. The invention application with publication number CN111233452A provides a high-frequency and high-impedance iron-poor manganese-zinc ferrite and a preparation method thereof, whose Curie temperature can reach 170°C, but its magnetic permeability is only 2000, and the saturation magnetic induction intensity is also low, which limits its application in some fields, such as automotive electronics.

[0004] Therefore, there is a need for an iron-poor manganese-zinc ferrite material having both high Curie temperature and high magnetic permeability. Summary of the invention

[0005] 1. Problem to be solved

[0006] One of the purposes of the present invention is to provide a high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material, aiming to obtain a poor iron manganese zinc ferrite material with both initial magnetic permeability>3000 and Curie temperature>180°C, and at the same time further optimize the scheme to have a higher impedance in the high frequency range of 1MHZ to 500MHZ.

[0007] Another object of the present invention is to provide a method for preparing a low-iron manganese zinc ferrite material with high magnetic permeability and high Curie temperature, so as to prepare the low-iron manganese zinc ferrite material required above.

[0008] 2. Technical solution

[0009] In order to solve the above problems, the technical solution adopted by the present invention is as follows:

[0010] According to the purpose of the present invention, in order to ensure that the material has both high magnetic permeability and high Curie temperature, the first aspect of the present invention provides a high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material, including main materials and auxiliary materials:

[0011] The main ingredients are composed of iron compounds, zinc compounds, cobalt compounds and manganese compounds. 2 O 3 The conversion amount is 46-50 mol%, the zinc compound is 12-16 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The conversion amount is 1 to 3 mol%, and the manganese compound is calculated as the balance in terms of MnO conversion amount; the auxiliary material comprises TiO 2 、CaCO 3 、V 2 O 5 、SiO 2 , Nb 2 O 5 .

[0012] Furthermore, in the main material, the iron compound is Fe 2 O 3 The conversion amount is 48-50 mol%, the zinc compound is 13-15 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount is 1.1 to 1.6 mol%, and the manganese compound is the balance in terms of MnO.

[0013] Furthermore, the applicant introduces the Co element into the main material to control the high Curie temperature, that is, the Curie temperature Tc of the ferrite material satisfies the following conditions:

[0014] Tc=7.12×(a+3.8d-2c / 3)-125;

[0015] In the formula, a represents the molar content of the iron compound, d represents the molar content of the cobalt compound, and c represents the molar content of the zinc compound.

[0016] Furthermore, in the auxiliary material, TiO 2 500ppm~2000ppm of the total weight of the main material, CaCO 3 Accounting for 300ppm~600ppm of the total weight of the main material, V 2 O 5 Accounting for 200ppm~500ppm of the total weight of the main material, SiO 2 0ppm~100ppm of the total weight of the main material, Nb 2 O 5 It accounts for 100ppm to 400ppm of the total weight of the main material.

[0017] Furthermore, in the auxiliary material, TiO 2 Accounting for 1000ppm~2000ppm of the total weight of the main material, CaCO 3 Accounting for 500ppm~600ppm of the total weight of the main material, V 2 O 5 Accounting for 200ppm~400ppm of the total weight of the main material, SiO 2 Accounting for 40ppm~100ppm of the total weight of the main material, Nb 2 O 5 It accounts for 100ppm to 200ppm of the total weight of the main material.

[0018] Furthermore, in the auxiliary material, CaCO 3 and SiO 2 The weight ratio is 1:2.

[0019] The second aspect of the present invention provides a method for preparing a high magnetic permeability and high Curie temperature iron-poor manganese-zinc ferrite, comprising the following steps:

[0020] S1, batching process: weigh the main material and auxiliary material according to the above proportion, add deionized water to the main material for sand grinding, and spray dry to obtain the spray material;

[0021] S2, pre-burning process: pre-burning the spray material to obtain pre-burned material;

[0022] S3, secondary sand grinding process: after adding auxiliary materials to the pre-burned material, add deionized water for secondary sand grinding to obtain secondary sand abrasive;

[0023] S4, spray granulation step: spray granulation of the secondary sand abrasive to obtain iron-poor manganese-zinc ferrite granulated powder;

[0024] S5, forming process: forming the iron-poor manganese-zinc ferrite granulated powder into a ring blank;

[0025] S6. Sintering process: sinter the ring blank at 1250°C to 1330°C, and control the oxygen content of the atmosphere to 1% to 5%, so as to obtain high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite.

[0026] Furthermore, in step S2, the pre-firing temperature of the pre-firing process is 800-950° C., and the pre-firing time is 2-5 hours.

[0027] Furthermore, in step S3, the time of the secondary sand grinding process is controlled within 30 min to 90 min, and the particle size distribution is controlled within D50: 1.0 μm to 1.6 μm.

[0028] Furthermore, in step S6, the sintering process is sintering in a staged variable speed temperature rise, and the sintering temperature change curve is:

[0029] Raise the temperature from room temperature to 400-600°C at a rate of 2-4°C / min and keep warm for 2-4h;

[0030] Continue heating to 900-1100°C at a heating rate of 2-5°C / min;

[0031] Continue to heat up to 1250-1330°C at a heating rate of 1-3°C / min, and keep at 1250-1330°C for 4-8h;

[0032] After the insulation is completed, cool to room temperature at a rate of 2 to 5°C / min.

[0033] The manganese-zinc ferrite of the prior art is difficult to achieve the technical problem of high magnetic permeability and high Curie temperature at the same time. When the above technical solution is adopted, the poor iron manganese-zinc ferrite material of the present invention is adopted, and the poor iron manganese-zinc ferrite obtained by the special sintering process is obtained by adjusting the appropriate proportion of the four main ingredients of iron compound, zinc compound, cobalt compound and manganese compound to achieve an initial magnetic permeability>3000 and a Curie temperature>180°C. The high frequency 1MHZ to 500MHZ in the further optimized solution has a higher impedance. It is fully adapted to the application requirements of automotive electronics and other high-temperature working scenes, and realizes the coexistence of high magnetic permeability, high Curie temperature, high saturation magnetic induction intensity, and high impedance. Compared with the poor iron manganese-zinc ferrite published by peers, while maintaining the high magnetic permeability and high impedance characteristics, the Curie temperature and saturation magnetic induction intensity have also been greatly improved.

[0034] 3. Beneficial effects

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] Compared with the poor iron manganese zinc ferrite materials published by peers, the high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of the present invention has greatly improved Curie temperature and saturation magnetic induction intensity while maintaining high magnetic permeability and high impedance characteristics; it is fully adapted to the application requirements of automotive electronics and other high-temperature working scenarios, and achieves the coexistence of high magnetic permeability, high Curie temperature, high saturation magnetic induction intensity and high impedance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The permeability-temperature comparison curve of the ferrite material of Example 1 of the present invention and the high Curie temperature iron-poor material of the commercially available ferrite material is shown. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0039] In view of the deficiencies in the prior art mentioned in the background technology, a specific embodiment of the present invention provides a high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material, including main materials and auxiliary materials:

[0040] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds. 2 O 3 The conversion amount is 46-50 mol%, the zinc compound is 12-16 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount is 1 to 3 mol%, and the manganese compound is calculated as the balance in terms of MnO converted amount;

[0041] The auxiliary materials include TiO 2 、CaCO 3 、V 2 O 5 、SiO 2 , Nb 2 O 5 .

[0042] It has been found that by adjusting the appropriate ratios of iron compound, zinc compound, cobalt compound and manganese compound within the scope of the present invention, a synergistic effect between the components is formed, so that the iron-poor manganese-zinc ferrite material can have a high magnetic permeability and a high Curie temperature.

[0043] For example, iron compounds are Fe 2 O 3 The converted amounts were 46 mol%, 47 mol%, 48 mol%, 48.5 mol%, 49 mol%, and 50 mol%.

[0044] For example, the zinc compound is contained in an amount of 12 mol%, 13 mol%, 13.8 mol%, 14 mol%, or 15 mol% in terms of ZnO.

[0045] For example, cobalt compounds are Co 2 O 3 The converted amounts were 1 mol%, 1.15 mol%, 1.2 mol%, 2 mol%, and 3 mol%.

[0046] For example, the amount of the manganese compound in terms of MnO is 33 mol%, 35.5 mol%, 35.85 mol%, 37 mol%, 37.7 mol%, 38.85 mol%, and 41 mol%.

[0047] In some embodiments, the iron compound is Fe 2 O 3 The amount of the zinc compound is 13.8 mol% in terms of ZnO conversion, and the amount of the cobalt compound is 13.8 mol% in terms of Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound was the balance in terms of MnO.

[0048] In some embodiments, the iron compound is Fe 2 O 3 The amount of the zinc compound is 13 mol% in terms of ZnO, and the amount of the cobalt compound is 13 mol% in terms of Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound was the balance in terms of MnO.

[0049] In some embodiments, the iron compound is Fe 2 O 3 The amount of the zinc compound is 15 mol% in terms of ZnO, and the amount of the cobalt compound is 15 mol% in terms of Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound was the balance in terms of MnO.

[0050] In some embodiments, the iron compound is Fe 2 O 3 The amount of the zinc compound is 14 mol% in terms of ZnO, and the amount of the cobalt compound is 14 mol% in terms of Co 2 O 3 The converted amount was 1.2 mol%, and the manganese compound was the balance in terms of MnO.

[0051] At the same time, the proportion of the main material is adjusted to obtain not only high magnetic permeability and high Curie temperature, but also improved impedance: in the main material, the iron compound is Fe 2 O 3 The conversion amount is 48-50 mol%, the zinc compound is 13-15 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount is 1.1 to 1.6 mol%, and the manganese compound is the balance in terms of MnO.

[0052] In addition, by introducing Co element into the main material to control the high Curie temperature, the Curie temperature Tc of the ferrite material can be controlled, that is,

[0053] Tc=7.12×(a+3.8d-2c / 3)-125;

[0054] In the formula, a represents the molar content of the iron compound, d represents the molar content of the cobalt compound, and c represents the molar content of the zinc compound.

[0055] When the above Curie temperature relationship is met, the initial magnetic permeability of the ferrite material is >3000, the Curie temperature is >180°C, and the high frequency of 1MHZ to 500MHZ has a higher impedance, achieving the coexistence of high magnetic permeability, high Curie temperature, high saturation magnetic induction intensity, and high impedance.

[0056] In order to optimize the performance of iron-poor manganese-zinc ferrite, TiO 2 500ppm~2000ppm of the total weight of the main material, CaCO 3 Accounting for 300ppm~600ppm of the total weight of the main material, V 2 O 5 Accounting for 200ppm~500ppm of the total weight of the main material, SiO 2 0ppm~100ppm of the total weight of the main material, Nb 2 O 5 It accounts for 100ppm to 400ppm of the total weight of the main material.

[0057] In some examples, TiO 2 Accounting for 1000ppm~2000ppm of the total weight of the main material, CaCO 3 Accounting for 500ppm~600ppm of the total weight of the main material, V 2 O 5 Accounting for 200ppm~400ppm of the total weight of the main material, SiO 2 Accounting for 40ppm~100ppm of the total weight of the main material, Nb 2 O 5 It accounts for 100ppm to 200ppm of the total weight of the main material.

[0058] According to another embodiment of the present invention, a method for preparing a high magnetic permeability and high Curie temperature iron-poor manganese-zinc ferrite is provided, comprising the following steps:

[0059] S1, batching process: weigh the main material and auxiliary material according to the above proportion, add deionized water to the main material for sand grinding, and spray dry to obtain the spray material;

[0060] S2, pre-burning process: pre-burning the spray material to obtain pre-burned material;

[0061] S3, secondary sand grinding process: after adding auxiliary materials to the pre-burned material, add deionized water for secondary sand grinding to obtain secondary sand abrasive;

[0062] S4, spray granulation step: spray granulation of the secondary sand abrasive to obtain iron-poor manganese-zinc ferrite granulated powder;

[0063] S5, forming process: forming the iron-poor manganese-zinc ferrite granulated powder into a ring blank;

[0064] S6. Sintering process: sinter the ring blank at 1250°C to 1330°C, and control the oxygen content of the atmosphere to 1% to 5%, so as to obtain high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite.

[0065] In some examples, in step S2, the pre-firing temperature of the pre-firing process is 800-950° C., and the pre-firing time is 2-5 hours.

[0066] In some examples, in step S3, the time of the secondary sand grinding process is controlled within 30 min to 90 min, and the particle size distribution is controlled within D50: 1.0 μm to 1.6 μm.

[0067] In some examples, in step S6, the sintering process is sintering in a staged variable speed temperature rise, and the sintering temperature variation curve is:

[0068] Raise the temperature from room temperature to 400-600°C at a rate of 2-4°C / min and keep warm for 2-4h;

[0069] Continue heating to 900-1100°C at a heating rate of 2-5°C / min;

[0070] Continue to heat up to 1250-1330°C at a heating rate of 1-3°C / min, and keep at 1250-1330°C for 4-8h;

[0071] After the insulation is completed, cool to room temperature at a rate of 2 to 5°C / min.

[0072] In some examples, the initial magnetic permeability of the poor iron manganese zinc ferrite after sintering in step S6 is >3000, for example, the initial magnetic permeability of the poor iron manganese zinc ferrite is 3280, 3030, 3050, 3070, 3140, 3160, or 3520.

[0073] In some examples, the Curie temperature of the iron-poor manganese-zinc ferrite after sintering in step S6 is > 180°C, for example, the Curie temperature of the iron-poor manganese-zinc ferrite is 180°C, 181°C, 185°C, 186°C, 196°C, or 203°C.

[0074] In some examples, the poor iron manganese zinc ferrite sintered in step S6 has a relatively high impedance at a high frequency of 1 MHZ to 500 MHZ. For example, the poor iron manganese zinc ferrite has an impedance of 105-120Ω at a high frequency of 1 MHZ to 500 MHZ.

[0075] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0076] Example 1

[0077] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment comprises main materials and auxiliary materials:

[0078] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3 The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0079] The auxiliary material comprises TiO 2 、CaCO 3 、V 2 O 5 , Nb 2 O 5 、SiO 2 , where TiO 2 1000ppm of the total weight of the main material, CaCO 3 500ppm of the total weight of the main material, V 2 O 5 200ppm of the total weight of the main material, Nb 2 O 5 Accounting for 200ppm of the total weight of the main material, SiO 2 It accounts for 40ppm of the total weight of the main material.

[0080] The method for preparing the high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite of this embodiment comprises the following steps:

[0081] S1, batching process: weigh the main material and auxiliary material according to the above proportion, add deionized water to the main material for sand grinding, and spray dry to obtain the spray material;

[0082] S2, pre-burning process: pre-burn the spray material, the pre-burning temperature is 800-950°C, the pre-burning time is 2-5 hours, and the pre-burned material is obtained;

[0083] S3, secondary sand grinding process: after adding auxiliary materials to the pre-burned material, add deionized water for secondary sand grinding, the time is controlled within 30min to 90min, and the particle size distribution is controlled within D50: 1.0μm to 1.6μm, to obtain secondary sand abrasive;

[0084] S4, spray granulation step: spray granulation of the secondary sand abrasive to obtain iron-poor manganese-zinc ferrite granulated powder;

[0085] S5, forming process: forming the iron-poor manganese-zinc ferrite granulated powder into a ring blank;

[0086] S6, sintering process: the ring blank is sintered at 1250℃~1330℃, and the oxygen content of the sintering atmosphere is controlled at 1%~5%. The sintering process is sintering in a staged variable speed heating process, and the sintering temperature change curve is:

[0087] Raise the temperature from room temperature to 400-600°C at a rate of 2-4°C / min and keep warm for 2-4h;

[0088] Continue heating to 900-1100°C at a heating rate of 2-5°C / min;

[0089] Continue to heat up to 1250-1330°C at a heating rate of 1-3°C / min, and keep at 1250-1330°C for 4-8h;

[0090] After the heat preservation is completed, the mixture is cooled to room temperature at a rate of 2-5°C / min to obtain the high magnetic permeability and high Curie temperature iron-poor manganese-zinc ferrite of the present embodiment.

[0091] Example 2

[0092] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment is basically the same as that of embodiment 1, except that the proportion of the main ingredients is: the iron compound is Fe 2 O 3 The conversion amount is 50 mol%, the zinc compound is 13 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0093] The preparation method is the same as that in Example 1.

[0094] Example 3

[0095] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment is basically the same as that of embodiment 1, except that the proportion of the main ingredients is: the iron compound is Fe 2 O 3 The conversion amount is 48 mol%, the zinc compound is 15 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0096] The preparation method is the same as that in Example 1.

[0097] Example 4

[0098] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment is basically the same as that of embodiment 1, except that the proportion of the main ingredients is: the iron compound is Fe 2 O 3 The conversion amount is 49 mol%, and the zinc compound is 14 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount was 1.2 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0099] The preparation method is the same as that in Example 1.

[0100] Example 5

[0101] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment is basically the same as that of embodiment 1, except that the proportion of the main ingredients is: the iron compound is Fe 2 O 3 The conversion amount is 47 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0102] The preparation method is the same as that in Example 1.

[0103] Example 6

[0104] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment is basically the same as that of embodiment 1, except that the proportion of the main ingredients is: the iron compound is Fe 2 O 3The conversion amount is 48.5 mol%, the zinc compound is 16 mol% in terms of ZnO conversion, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0105] The preparation method is the same as that in Example 1.

[0106] Example 7

[0107] The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material of this embodiment is basically the same as that of embodiment 1, except that the proportion of the main ingredients is: the iron compound is Fe 2 O 3 The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.8 mol%, and the manganese compound accounted for the remainder in terms of MnO.

[0108] The preparation method is the same as that in Example 1.

[0109] Comparative Example 1

[0110] The manganese-zinc ferrite material of Comparative Example 1 comprises the following main materials and auxiliary materials:

[0111] The main ingredients are iron compounds, zinc compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3 The amount of the zinc compound was 48.5 mol % in terms of ZnO conversion, and the amount of the manganese compound was 37.7 mol % in terms of MnO conversion.

[0112] The auxiliary material comprises TiO 2 、CaCO 3 、V 2 O 5 , Nb 2 O 5 、SiO 2 , where TiO 2 1000ppm of the total weight of the main material, CaCO 3 500ppm of the total weight of the main material, V 2 O 5 200ppm of the total weight of the main material, Nb 2 O 5 Accounting for 200ppm of the total weight of the main material, SiO 2 It accounts for 40ppm of the total weight of the main material.

[0113] The preparation method is the same as that of Example 1, except that the main material does not contain cobalt compounds.

[0114] Comparative Example 2

[0115] The manganese-zinc ferrite material of Comparative Example 2 comprises the following main ingredients and auxiliary ingredients:

[0116] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3 The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the amount of the manganese compound was 36.55 mol% in terms of MnO.

[0117] The auxiliary material is composed of CaCO 3 、V 2 O 5 、SiO 2 , Nb 2 O 5 , among which CaCO 3 500ppm of the total weight of the main material, V 2 O 5 Accounting for 200ppm of the total weight of the main material, SiO 2 Accounting for 40ppm of the total weight of the main material, Nb 2 O 5 It accounts for 200ppm of the total weight of the main material.

[0118] The preparation method is the same as that of Example 1, except that no TiO 2 .

[0119] Comparative Example 3

[0120] The manganese-zinc ferrite material of Comparative Example 3 comprises the following main materials and auxiliary materials:

[0121] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3 The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the amount of the manganese compound was 36.55 mol% in terms of MnO.

[0122] The auxiliary material comprises TiO 2 、V 2 O 5 , Nb2 O 5 , where TiO 2 1000ppm of the total weight of the main material, V 2 O 5 200ppm of the total weight of the main material, Nb 2 O 5 It accounts for 200ppm of the total weight of the main material.

[0123] The preparation method is the same as that of Example 1, except that no CaCO is added. 3 、SiO 2 .

[0124] Comparative Example 4

[0125] The manganese-zinc ferrite material of Comparative Example 4 comprises the following main materials and auxiliary materials:

[0126] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3 The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the amount of the manganese compound was 36.55 mol% in terms of MnO.

[0127] The auxiliary material comprises TiO 2 、CaCO 3 、SiO 2 , Nb 2 O 5 , where TiO 2 1000ppm of the total weight of the main material, CaCO 3 500ppm of the total weight of the main material, SiO 2 Accounting for 40ppm of the total weight of the main material, Nb 2 O 5 It accounts for 200ppm of the total weight of the main material.

[0128] The preparation method is the same as that of Example 1, except that V is not added. 2 O 5 .

[0129] Comparative Example 5

[0130] The manganese-zinc ferrite material of Comparative Example 5 comprises the main material and auxiliary materials:

[0131] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 1.15 mol%, and the amount of the manganese compound was 36.55 mol% in terms of MnO.

[0132] The auxiliary material comprises TiO 2 、CaCO 3 、V 2 O 5 、SiO 2 , where TiO 2 1000ppm of the total weight of the main material, CaCO 3 500ppm of the total weight of the main material, V 2 O 5 Accounting for 200ppm of the total weight of the main material, SiO 2 40ppm of the total weight of the main material,

[0133] The preparation method is the same as that of Example 1, except that no Nb2O5 is added.

[0134] Comparative Example 6

[0135] The manganese-zinc ferrite material of Comparative Example 6 comprises a main material and an auxiliary material: comprising a main material and an auxiliary material:

[0136] The main ingredients are iron compounds, zinc compounds, cobalt compounds and manganese compounds, among which the iron compounds are mainly Fe 2 O 3 The conversion amount is 48.5 mol%, the zinc compound is 13.8 mol% in terms of ZnO, and the cobalt compound is Co 2 O 3 The converted amount was 0.8 mol%, and the amount of the manganese compound was 36.9 mol% in terms of MnO.

[0137] The auxiliary material comprises TiO 2 、CaCO 3 、V 2 O 5 , Nb 2 O 5 、SiO 2 , where TiO 2 1000ppm of the total weight of the main material, CaCO 3 500ppm of the total weight of the main material, V 2 O 5 200ppm of the total weight of the main material, Nb 2 O 5 Accounting for 200ppm of the total weight of the main material, SiO 2It accounts for 40ppm of the total weight of the main material.

[0138] The preparation method is the same as that in Example 1.

[0139] Performance Testing

[0140] The measured and theoretically calculated values ​​of the magnetic permeability, impedance and Curie temperature of the iron-poor manganese-zinc ferrite under broadband conditions obtained in each embodiment and comparative example are shown in Table 1:

[0141] Table 1 Performance test of iron-poor manganese-zinc ferrite obtained in each embodiment and comparative example

[0142]

[0143] It can be seen from Table 1 that:

[0144] The initial magnetic permeability of the iron-poor manganese-zinc ferrite in Examples 1 to 7 of the present application is greater than 3000, and the measured values ​​of the Curie temperature are all greater than 180°C. At the same time, the calculated value of the Curie temperature is within 6°C of the measured value, indicating that the formula of the present application has certain guiding significance.

[0145] The main material ratio of the iron-poor manganese-zinc ferrite of Examples 1 to 4 of the present application is better than that of Examples 5 to 7. It is measured that the impedance of the iron-poor manganese-zinc ferrite of Examples 1 to 4 is higher.

[0146] It can be seen from the comparison between Comparative Example 1 and Example 1 that in the absence of cobalt compounds, the initial magnetic permeability and Curie temperature are not high, indicating that adding cobalt compounds to the main material is beneficial to simultaneously improving the initial magnetic permeability and Curie temperature.

[0147] Comparative Examples 2 to 5 illustrate that the lack of one or two components in the auxiliary materials will affect the initial magnetic permeability.

[0148] Comparative Example 6 illustrates the effect of a small amount of cobalt compound in the main material on the magnetic permeability and Curie temperature.

[0149] In addition, the applicant made a ui-T curve for the iron-poor manganese-zinc ferrite obtained in Example 1 and three commercially available iron-poor manganese-zinc ferrites as shown in Figure 1 As shown in the figure, HFZ3 is the iron-poor manganese-zinc ferrite obtained in Example 1, DMR32 is DMEGC Materials (DMEGC Co., Ltd. of Hengdian Group), Ti30 is Tiantong Materials (Tiantong Holdings Co., Ltd.), and JPZ-3 is AnciGC Materials (Jiangmen AnciGC Electronics Co., Ltd.). All of the above are iron-poor materials launched by various companies. The Curie temperature of the ferrite in this application is greater than 180°C.

[0150] The raw materials and equipment used in the present invention, unless otherwise specified, are all commonly used raw materials and equipment in the art; the methods used in the present invention, unless otherwise specified, are all conventional methods in the art. The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiments according to the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. High magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material, characterized by: It includes main materials and auxiliary materials: the main materials are composed of iron compounds, zinc compounds, cobalt compounds and manganese compounds, the iron compound is 46-50 mol% calculated on the basis of Fe2O3, the zinc compound is 12-16 mol% calculated on the basis of ZnO, the cobalt compound is 1-3 mol% calculated on the basis of Co2O3, and the manganese compound is the remainder calculated on the basis of MnO; the auxiliary materials include TiO2, CaCO3, V2O5, SiO2 and Nb2O5.

2. The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material according to claim 1, characterized in that: In the main material, the iron compound is 48-50 mol% in terms of Fe2O3 conversion, the zinc compound is 13-15 mol% in terms of ZnO conversion, the cobalt compound is 1.1-1.6 mol% in terms of Co2O3 conversion, and the manganese compound is the balance in terms of MnO conversion.

3. The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material according to claim 1 or 2, characterized in that: The Curie temperature Tc of ferrite materials meets the following conditions: Tc=7.12×(a+3.8d-2c / 3)-125; In the formula, a represents the molar content of the iron compound, d represents the molar content of the cobalt compound, and c represents the molar content of the zinc compound.

4. The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material according to claim 3, characterized in that: Among the auxiliary materials, TiO2 accounts for 500ppm to 2000ppm of the total weight of the main material, CaCO3 accounts for 300ppm to 600ppm of the total weight of the main material, V2O5 accounts for 200ppm to 500ppm of the total weight of the main material, SiO2 accounts for 0ppm to 100ppm of the total weight of the main material, and Nb2O5 accounts for 100ppm to 400ppm of the total weight of the main material.

5. The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material according to claim 3, characterized in that: Among the auxiliary materials, TiO2 accounts for 1000ppm to 2000ppm of the total weight of the main material, CaCO3 accounts for 500ppm to 600ppm of the total weight of the main material, V2O5 accounts for 200ppm to 400ppm of the total weight of the main material, SiO2 accounts for 40ppm to 100ppm of the total weight of the main material, and Nb2O5 accounts for 100ppm to 200ppm of the total weight of the main material.

6. The high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite material according to claim 3, characterized in that: Among the auxiliary materials, the weight ratio of CaCO3 and SiO2 is 1:

2.

7. A method for preparing a high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite, comprising the following steps: S1, batching process: weigh the main material and auxiliary material according to the proportion of the poor iron manganese zinc ferrite material in any one of claims 1 to 6, add deionized water to the main material for sand grinding, and spray dry to obtain the spray material; S2, pre-burning process: pre-burning the spray material to obtain pre-burned material; S3, secondary sand grinding process: after adding auxiliary materials to the pre-burned material, add deionized water for secondary sand grinding to obtain secondary sand abrasive; S4, spray granulation step: spray granulation of the secondary sand abrasive to obtain iron-poor manganese-zinc ferrite granulated powder; S5, forming process: forming the iron-poor manganese-zinc ferrite granulated powder into a ring blank; S6. Sintering process: sinter the ring blank at 1250°C to 1330°C, and control the oxygen content of the atmosphere to 1% to 5%, so as to obtain high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite.

8. The method for preparing high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite according to claim 7, characterized in that: In step S2, the pre-firing temperature of the pre-firing process is 800 to 950°C, and the pre-firing time is 2 to 5 hours.

9. The method for preparing high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite according to claim 7, characterized in that: In step S3, the time of the secondary sand grinding process is controlled within 30 min to 90 min, and the particle size distribution is controlled within D50: 1.0 μm to 1.6 μm.

10. The method for preparing high magnetic permeability and high Curie temperature poor iron manganese zinc ferrite according to claim 7, characterized in that: In step S6, the sintering process is sintering in a staged variable speed temperature rise, and the sintering temperature change curve is: Raise the temperature from room temperature to 400-600°C at a rate of 2-4°C / min and keep warm for 2-4h; Continue heating to 900-1100°C at a heating rate of 2-5°C / min; Continue to heat up to 1250-1330°C at a heating rate of 1-3°C / min, and keep at 1250-1330°C for 4-8h; After the insulation is completed, cool to room temperature at a rate of 2 to 5°C / min.

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