CN115947594B - High-frequency band ferrite material and preparation method thereof - Google Patents
High-frequency band ferrite material and preparation method thereof Download PDFInfo
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Abstract
The invention relates to a high-frequency band ferrite material and a preparation method thereof, wherein the high-frequency band ferrite material comprises main components and auxiliary components, and the main components comprise the following components in parts by mole: 49-50mol% Fe 2 O 3 4-8mol% ZnO, 40-43mol% NiO and 6-8.5mol% CuO; the auxiliary component comprises the following components in percentage by weight, based on 100% of the total mass of the main component, of 0.15% by weight of Bi 2 O 3 、0.12wt％CaO、0.1wt％BaTiO 3 Meanwhile, a preparation method for preparing the ferrite material is also disclosed. The ferrite of the invention has the characteristics of high frequency band, stable performance, low production process cost and stable process.
Description
Technical Field
The invention relates to the field of magnetic materials, in particular to a high-frequency band ferrite material and a preparation method thereof.
Background
Ferrite is a novel nonmetallic magnetic material developed in the 40 th century. Along with the development of electronic devices and communication technologies, high-frequency ferrite is widely applied to various communication and electronic fields, and has higher requirements on materials and higher requirements on the properties of the materials. The existing high-frequency ferrite has unstable performance and high loss, and can not meet the requirements of the market on the comprehensive characteristics of materials.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a high-frequency band ferrite material capable of being rapidly cooled, effectively removing stress and reducing deformation degree and a preparation method thereof.
The technical scheme adopted for solving the technical problems is as follows: a high-frequency band ferrite material: the composite material comprises a main component and an auxiliary component, wherein the main component comprises the following components in parts by mole: 49-50mol% Fe 2 O 3 4-8mol% ZnO, 40-43mol% NiO and 6-8.5mol% CuO; the auxiliary component comprises the following components in percentage by weight, based on 100% of the total mass of the main component, of 0.15% by weight of Bi 2 O 3 、0.12wt％CaO、0.1wt％BaTiO 3 。
A preparation method of a high-frequency band ferrite material comprises the following steps:
s1, mixing the main ingredient ingredients and performing primary ball milling;
s2, drying the mixture after ball milling;
s3, presintering the dried mixture for a certain time, and naturally cooling to room temperature to obtain an intermediate product;
s4, doping the auxiliary components into the intermediate product;
s5, performing secondary ball milling on the intermediate product doped with the auxiliary components;
s6, drying and sieving the product after the secondary ball milling, and adding PVA with the weight percentage of 15wt% into the product passing through the mesh sieve for mixing;
s7, molding the mixture mixed with PVA on a mold;
and S8, sintering the molded product at a certain temperature for a certain time.
Preferably, the primary ball milling in the step S1 is performed by using steel balls, wherein the steel balls comprise steel balls with the diameter of 8mm and steel balls with the diameter of 6mm, and the steel balls are in weight percentage during ball milling: the main components are as follows: the water is 3.3:1:1.5, the ball milling rotating speed is 241rpm, and the ball milling time is 3 hours.
Preferably, the step S2 is to bake in an oven at 80 ℃ for 8 hours.
Preferably, the presintering in the step S3 is presintering under the condition that the temperature is 900 ℃, and the method comprises the following steps:
s3a, heating, namely heating from the room temperature of 20 ℃ to 900 ℃ at a speed of 2.0 ℃/min for 440min;
s3b, heat preservation is carried out, and heat preservation is carried out for 150min at the temperature of 900 ℃;
s3c, cooling, and naturally cooling to room temperature from 900 ℃ to obtain an intermediate product.
Preferably, the secondary ball ink in the step S5 is ball-milled by using zirconium balls with the diameter of 5mm, and the weight percentage of the zirconium balls is as follows: intermediate product: the water is 3.3:1:1.5, the ball milling rotating speed is 241rpm, and the ball milling time is 6 hours.
Preferably, the step S6 is to bake for 8 hours in an oven at 80 ℃, and then sequentially pass through a 40-mesh sieve and a 200-mesh sieve after baking.
Preferably, the step S7 is performed by pressing the mold for 10S for 8 MPa.
Preferably, the step S8 is performed by sintering,
s8a, heating from room temperature to 300 ℃ at a heating rate of 1.5 ℃/min;
s8b, raising the temperature from 300 ℃ to 550 ℃ at a heating rate of 0.8 ℃/min;
s8c, heating from 550 ℃ to 750 ℃ at a heating rate of 2 ℃/min;
s8d, raising the temperature from 750 ℃ to 900 ℃ at a heating rate of 1.5 ℃/min;
s8e, rising the temperature from 900 ℃ to 1080-1100 ℃ at a heating rate of 1.0 ℃/min;
s8f, preserving heat for 3-5h at 1080-1100 ℃;
s8g, cooling from 1080-1100 ℃ to 1000 ℃ at a cooling rate of 1.0 ℃/min;
s8h, reducing the temperature from 1000 ℃ to 300 ℃ at a cooling rate of 2.0 ℃/min;
s8i, cooling from 300 ℃ to room temperature by natural cooling.
Preferably, in the step S8f, the temperature is 1080, the heat is preserved for 5 hours, and the temperature is 1100 ℃ and the heat is preserved for 3-5 hours.
The invention has the beneficial effects that: the material has the characteristics of high frequency band and low loss, optimizes the performance of ferrite, ensures that the ferrite has better comprehensive performance and more stable performance, and meets the comprehensive performance requirement of the market on the material. The preparation process has low cost, and the sintering temperature, the heat preservation time and the temperature rise and fall curve are stable by changing the contents of all components.
Detailed Description
For the purpose of illustrating more clearly the objects, technical solutions and advantages of embodiments of the present invention, the present invention will be further described in conjunction with the following embodiments, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by a person skilled in the art without any inventive effort, are intended to be within the scope of the present invention, based on the embodiments of the present invention.
The embodiment of the invention discloses a high-frequency band ferrite material: comprises main components and auxiliary components, wherein the main components compriseThe components with the following molar contents: 49-50mol% Fe 2 O 3 4-8mol% ZnO, 40-43mol% NiO and 6-8.5mol% CuO; the auxiliary component comprises the following components in percentage by weight, based on 100% of the total mass of the main component, of 0.15% by weight of Bi 2 O 3 、0.12wt％CaO、0.1wt％BaTiO 3 . By reacting Fe with 2 O 3 Adjusting the NiO content to optimize the saturation magnetic flux density, initial magnetic permeability, magnetic permeability temperature factor and Curie temperature of the material; the use frequency of the material is adjusted through the adjustment of ZnO content; the sintering temperature of the material is adjusted by adjusting the CuO content. Nano CaO is added into the minor components to improve the stress resistance of the material at different temperatures; adding nano Bi into the minor components 2 O 3 Reducing the sintering temperature to promote densification to improve the saturation magnetic flux density characteristics of the material, and having a cubic fluorite type structure in which 1/4 of oxygen ion sites in the crystal lattice are vacant, thus having very high oxygen ion conductivity; baTiO 3 The incident electromagnetic wave can be attenuated in an absorbed form and mainly dispersed by the thermal effect, when the angular frequency generated by the magnetocrystalline anisotropy of the ferrite is similar to the angular frequency generated by the incident electromagnetic field, resonance can be generated, and at the moment, baTiO 3 The energy is variably absorbed from the outside, so that the attenuation of electromagnetic energy is reduced, the thickness of a grain boundary is increased through the combination and addition of auxiliary components, and the temperature factors of the relative loss factor and the magnetic permeability of a high-frequency band are reduced; the crystal structure and grain boundary distribution of the material are further adjusted through the production process, so that the material has the characteristics of low permeability and low loss, and the material has the characteristics of low loss in a high frequency band, so that the ferrite has better comprehensive performance and stable performance, and the comprehensive performance requirement of the market on the material is met.
A preparation method of a high-frequency band ferrite material comprises the following steps:
s1, mixing the main ingredient ingredients, and performing primary ball milling, namely, the components with molar contents: 49-50mol% Fe 2 O 3 Mixing 4-8mol% ZnO, 40-43mol% NiO and 6-8.5mol% CuO, and mixing with abrasivePerforming primary ball milling, wherein the grinding material selects steel balls, the steel balls comprise steel balls with the diameter of 8mm and steel balls with the diameter of 6mm, and the proportion of the steel balls to the main components and water is as follows in percentage by weight during ball milling: the main components are as follows: the water is 3.3:1:1.5, the ball milling rotating speed is 241rpm, the ball milling time is 3 hours, 335g of steel balls with the diameter of 8mm and 335g of steel balls with the diameter of 6mm are selected in the examples, the main component is 200g, and the ball milling is carried out on 300g of water;
s2, drying the mixture after ball milling, namely, drying the mixture after ball milling in an oven at 80 ℃ for 8 hours;
s3, presintering the dried mixture for a certain time, and naturally cooling to room temperature to obtain an intermediate product, wherein the presintering is performed at 900 ℃, specifically, firstly, the temperature is increased from the room temperature of 20 ℃ to 900 ℃ at a speed of 2.0 ℃/min, and the heating time is 440min; then preserving heat at 900 ℃ for 150min; then naturally cooling the mixture to room temperature from 900 ℃ to obtain an intermediate product;
s4, doping the intermediate product with the auxiliary components, namely doping the intermediate product formed after presintering with 0.15wt% Bi 2 O 3 、0.12wt％CaO、0.1wt％BaTiO 3 In the examples, the specific doping ratio is shown below, wherein 200 is the total mass of the main component and the subcomponent, the units are g, the sample numbers represented by 1, 2 and 3, that is, parallel samples are simultaneously carried out, table 1 is the calculated value of the addition amount, table 2 is the actual measured value of the addition amount, and the values after the sample numbers in table 2 are the total mass of the main component and the subcomponent which are actually weighed;
| 1(200.0) | 2(200.0) | 3(200.0) | 4(200.0) | ||
| Bi 2 O 3 | 0.15wt％ | 0.31 | 0.31 | 0.31 | 0.31 |
| CaO | 0.12wt％ | 0.25 | 0.25 | 0.25 | 0.25 |
| BaTiO 3 | 0.10wt％ | 0.21 | 0.21 | 0.21 | 0.21 |
TABLE 1
| 1(198.1) | 2(200.1) | 3(200.6) | 4(199.0) | ||
| Bi 2 O 3 | 0.15wt％ | 0.31 | 0.31 | 0.31 | 0.31 |
| CaO | 0.12wt％ | 0.25 | 0.25 | 0.25 | 0.25 |
| BaTiO 3 | 0.10wt％ | 0.20 | 0.20 | 0.20 | 0.20 |
TABLE 2
S5, performing secondary ball milling on the intermediate product doped with the auxiliary components, wherein the grinding material is zirconium balls, the diameter of each zirconium ball is 5mm, and during ball milling, the weight percentage of the zirconium balls to the intermediate product to water is as follows: intermediate product: the water is 3.3:1:1.5, the ball milling rotating speed is 241rpm, the ball milling time is 6 hours, 660g of zirconium balls with the thickness of 5mm are selected in the examples, 200g of intermediate products and 300g of water are used for ball milling;
s6, drying and sieving the product after the secondary ball milling, adding PVA with 15 weight percent into the product passing through the mesh sieve, mixing, drying for 8 hours in an oven at 80 ℃, sequentially sieving the dried material with 40 meshes and 200 meshes, adding PVA with 15 weight percent into the product passing through the mesh sieve after sieving, mixing and granulating, wherein 15 weight percent of the PVA is calculated by 100 weight percent of the product after sieving;
s7, molding the mixture mixed with PVA on a mold, namely, firstly putting the material granulated in the previous step into the mold, then putting the mold on a press, and then pressurizing for 10 seconds under 8MPa to mold the material;
s8, sintering the molded product at a certain temperature for a certain time, wherein the sintering steps are as follows: firstly, raising the temperature from room temperature to 300 ℃ at a heating rate of 1.5 ℃/min; then raising the temperature from 300 ℃ to 550 ℃ at a heating rate of 0.8 ℃/min; then the temperature is increased from 550 ℃ to 750 ℃ at a heating rate of 2 ℃/min; then the temperature is increased from 750 ℃ to 900 ℃ at a heating rate of 1.5 ℃/min; finally, the temperature is increased from 900 ℃ to 1080-1100 ℃ at the heating rate of 1.0 ℃/min; then preserving heat for 3-5h at 1080-1100 ℃, wherein the final sintering temperature and the preserving heat time can be adopted according to different weight ingredients, for example, preserving heat for 5h at 1080 and preserving heat for 3-5h at 1100 ℃; the temperature reduction stage is carried out after the heat preservation is finished, and when the temperature is reduced, the temperature is reduced from 1080-1100 ℃ to 1000 ℃ at a temperature reduction rate of 1.0 ℃/min; then cooling from 1000 ℃ to 300 ℃ at a cooling rate of 2.0 ℃/min; and finally, naturally cooling to room temperature from 300 ℃ to obtain the final high-frequency band ferrite. The following tables are the performance parameters of the ferrite prepared at different sintering temperatures for the above-mentioned several samples, the table 3 is the product test parameters for sintering at 1080 ℃ for 5 hours, the table 4 is the product test parameters for sintering at 1100 ℃ for 3 hours, and the table 5 is the product test parameters for sintering at 1100 ℃ for 5 hours.
TABLE 3 Table 3
TABLE 4 Table 4
TABLE 5
It will be understood that modifications and variations will be apparent to those skilled in the art from the foregoing description, and it is intended that all such modifications and variations be included within the scope of the following claims.
Claims (8)
1. A high-band ferrite material, characterized in that: the composite material comprises a main component and an auxiliary component, wherein the main component comprises the following components in parts by mole: 49-50mol% Fe 2 O 3 4-8mol% ZnO, 40-43mol% NiO and 6-8.5mol% CuO; the auxiliary component comprises the following components in percentage by weight, based on 100% of the total mass of the main component, of 0.15% by weight of Bi 2 O 3 、0.12wt％CaO、0.1wt％BaTiO 3 。
2. A preparation method of a high-frequency band ferrite material is characterized by comprising the following steps:
s1, mixing the main ingredient ingredients in the method of claim 1 for primary ball milling;
s2, drying the mixture after ball milling;
s3, presintering the dried mixture for a certain time, naturally cooling to room temperature to obtain an intermediate product, wherein the presintering is performed under the condition that the temperature is 900 ℃, and the specific steps are as follows:
s3a, heating, namely heating from the room temperature of 20 ℃ to 900 ℃ at a speed of 2.0 ℃/min for 440min;
s3b, heat preservation is carried out, and heat preservation is carried out for 150min at the temperature of 900 ℃;
s3c, cooling, namely naturally cooling to room temperature from 900 ℃ to obtain an intermediate product;
s4, doping the auxiliary component in the claim 1 into the intermediate product;
s5, performing secondary ball milling on the intermediate product doped with the auxiliary components;
s6, drying and sieving the product after the secondary ball milling, and adding PVA with the weight percentage of 15wt% into the product passing through the mesh sieve for mixing;
s7, molding the mixture mixed with PVA on a mold;
s8, sintering the molded product at a certain temperature for a certain time, wherein the method comprises the following specific steps of:
s8a, heating from room temperature to 300 ℃ at a heating rate of 1.5 ℃/min;
s8b, raising the temperature from 300 ℃ to 550 ℃ at a heating rate of 0.8 ℃/min;
s8c, heating from 550 ℃ to 750 ℃ at a heating rate of 2 ℃/min;
s8d, raising the temperature from 750 ℃ to 900 ℃ at a heating rate of 1.5 ℃/min;
s8e, rising the temperature from 900 ℃ to 1080-1100 ℃ at a heating rate of 1.0 ℃/min;
s8f, preserving heat for 3-5h at 1080-1100 ℃;
s8g, cooling from 1080-1100 ℃ to 1000 ℃ at a cooling rate of 1.0 ℃/min;
s8h, reducing the temperature from 1000 ℃ to 300 ℃ at a cooling rate of 2.0 ℃/min;
s8i, cooling from 300 ℃ to room temperature by natural cooling.
3. The method for preparing the high-frequency band ferrite material according to claim 2, wherein the primary ball milling in the step S1 is performed by using steel balls, the steel balls comprise steel balls with diameters of 8mm and steel balls with diameters of 6mm, and the steel balls are in weight percentage during ball milling: the main components are as follows: the water is 3.3:1:1.5, the ball milling rotating speed is 241rpm, and the ball milling time is 3 hours.
4. The method of manufacturing a high-band ferrite material according to claim 2, wherein the step S2 is to bake in an oven at 80℃for 8 hours.
5. The method for preparing the high-frequency ferrite material according to claim 2, wherein the secondary ball ink in the step S5 is ball-milled by adopting zirconium balls with the diameter of 5mm, and the weight percentage of the zirconium balls is as follows: intermediate product: the water is 3.3:1:1.5, the ball milling rotating speed is 241rpm, and the ball milling time is 6 hours.
6. The method of manufacturing a high-band ferrite material according to claim 2, wherein the step S6 is to bake for 8 hours in an oven at 80℃and then sequentially pass through a 40 mesh sieve and a 200 mesh sieve.
7. The method of manufacturing a high-band ferrite material according to claim 2, wherein the step S7 is performed by pressing the mold for 10S under a pressure of 8 MPa.
8. The method for preparing a high-frequency band ferrite material according to claim 2, wherein the temperature in the step S8f is 1080, the temperature is kept for 5 hours, and the temperature is 1100 ℃ and the temperature is kept for 3-5 hours.
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| WO2013121972A1 (en) * | 2012-02-13 | 2013-08-22 | 戸田工業株式会社 | Ni-Zn-Cu-BASED FERRITE POWDER, GREEN SHEET COMPRISING SAID Ni-Zn-Cu-BASED FERRITE POWDER, AND SINTERED Ni-Zn-Cu-BASED FERRITE |
| CN103332928A (en) * | 2012-11-02 | 2013-10-02 | 横店集团东磁股份有限公司 | Soft-magnetic nickel-copper-zinc ferrite material and preparation method thereof |
| CN110655397A (en) * | 2019-11-04 | 2020-01-07 | 宝鸡文理学院 | Wide-temperature-range high-permeability low-loss NiCuZn soft magnetic ferrite material and preparation method thereof |
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| JP2006151741A (en) * | 2004-11-29 | 2006-06-15 | Tdk Corp | Ferrite material and electronic component using the same |
| EP2330604A4 (en) * | 2008-09-30 | 2018-03-28 | Soshin Electric Co. Ltd. | Composite electronic component |
| CN108558383B (en) * | 2018-04-04 | 2021-10-15 | 全球能源互联网研究院有限公司 | NiZn ferrite material and preparation method thereof |
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| WO2013121972A1 (en) * | 2012-02-13 | 2013-08-22 | 戸田工業株式会社 | Ni-Zn-Cu-BASED FERRITE POWDER, GREEN SHEET COMPRISING SAID Ni-Zn-Cu-BASED FERRITE POWDER, AND SINTERED Ni-Zn-Cu-BASED FERRITE |
| CN103332928A (en) * | 2012-11-02 | 2013-10-02 | 横店集团东磁股份有限公司 | Soft-magnetic nickel-copper-zinc ferrite material and preparation method thereof |
| CN110655397A (en) * | 2019-11-04 | 2020-01-07 | 宝鸡文理学院 | Wide-temperature-range high-permeability low-loss NiCuZn soft magnetic ferrite material and preparation method thereof |
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