Wide-temperature low-power-consumption magnetic core and preparation method thereof

Abstract

The application relates to the technical field of magnetic core processing, in particular to a wide-temperature low-power-consumption magnetic core and a preparation method thereof. The wide-temperature low-power-consumption magnetic core comprises a main component, a first auxiliary material and a second auxiliary material, the main component is composed of Fe2O3, ZnO and MnO; the first auxiliary material comprises CaCO3, ZrO2, Nb2O, Co2O3, nano SiO2 and nano TiO2; and the second auxiliary material comprises Ta2O5, V2O5, Bi2O3 and HfO2. By controlling the adding range of the main component and the first auxiliary material, the manganese-zinc ferrite basically has the performance of wide temperature and low power consumption; the second auxiliary material is added to modify the loss, so that there is a relatively low power loss at each temperature, the application range of the wide-temperature low-power-consumption magnetic core under extreme conditions can be solved to a great extent, and the requirements of high energy conversion rate, low power loss and wide-temperature use for the wide-temperature low-power-consumption magnetic core are met.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of magnetic core processing, in particular to a wide-temperature low-power-consumption magnetic core and a preparation method thereof. BACKGROUND

[0002] The magnetic core refers to a sintered magnetic metal oxide composed of various iron oxide mixtures, and the current superior magnetic core is mostly made of soft magnetic ferrite. The soft magnetic ferrite material has been developed for more than 80 years since it was successfully developed by the Philips Laboratory in the Netherlands in 1935. Since the magnetism of the ferrite is derived from the ferrimagnetism, the saturation magnetization intensity of the ferrite is lower than that of the metal magnet, but the resistivity p of the ferrite is much higher than that of the metal magnet, so the ferrite has good high-frequency characteristics. In the weak electric high-frequency technical field, the soft magnetic ferrite has unique advantages. The magnetic core made of the material is the core component of various inductors, electronic transformers, choke coils, suppressors and filters.

[0003] Due to the rapid development of the electronic information industry, the electronic product update and replacement speed is accelerated, and the product develops towards the environment-friendly type, energy-saving type and miniaturization. This makes the magnetic material, the basic material of the electronic product, develop unprecedentedly. The massive application in the communication industry, the IT industry, the automobile industry and the like promotes the rapid development of the high-performance ferrite product.

[0004] At present, the household electronic product gradually reduces the volume, and requires energy saving and consumption reduction, which leads to the development of the structure of the power transformer towards miniaturization and flattening, the product weight is greatly reduced, and the cost is reduced. The existing magnetic material cannot meet the needs of the development of the industry due to the limitation of the use temperature, the magnetic permeability and the power consumption. SUMMARY

[0005] The application aims at the shortage of the current technology, and provides a wide-temperature low-power-consumption magnetic core and a preparation method thereof.

[0006] In a first aspect, the application provides a wide-temperature low-power-consumption magnetic core, which adopts the following technical scheme:

[0007] The application discloses a wide-temperature low-power magnetic core, which comprises a main component, a first auxiliary material and a second auxiliary material, wherein the main component is composed of Fe2O3, ZnO and MnO in terms of mole fraction, and the content of Fe2O3 is 52.3-52.9 mol%, the content of ZnO is 7.58.2 mol%, and the rest is MnO; the first auxiliary material comprises CaCO3, ZrO2, Nb2O, Co2O3, nano-SiO2 and nano-TiO2; the content of each auxiliary component in the total weight of the main component is as follows: the content of CaCO3 is 0.03-0.05 wt%, the content of ZrO2 is 0.002-0.005 wt%, the content of Nb2O is 0.02-0.03 wt%, the content of Co2O3 is 0.20-0.26 wt%, the content of nano-SiO2 is 0.004-0.007 wt%, and the content of nano-TiO2 is 0.006-0.009 wt%; the second auxiliary material comprises Ta2O5, V2O5, Bi2O3 and HfO2; the content of each auxiliary component in the total weight of the main component is as follows: the content of Ta2O5 is 0.03-0.05 wt%, the content of V2O5 is 0.06-0.09 wt%, the content of Bi2O3 is 0.05-0.08 wt%, and the content of HfO2 is 0.01-0.04 wt%, the particle size of the nano-SiO2 is 20-40 nm, and the particle size of the nano-TiO2 is 40-80 nm.

[0008] By adopting the technical scheme, the main component Fe2O3, ZnO and MnO in the application are used to form the basis of the manganese-zinc ferrite, Fe2O3 provides magnetism, ZnO can improve the anti-saturation magnetic field capacity of the material, and MnO can increase the resistivity and specific permeability of the material. The first auxiliary material is mainly used to change the physical properties of the material by regulating the content of different elements. The addition of CaCO3 can promote the growth of the crystal grains and reduce the hysteresis loop, ZrO2 and Nb2O5 can improve the anti-saturation magnetic field capacity of the material, the addition of Co2O3 can increase the anti-magnetic field thermal stability of the material, and the addition of nano-SiO2 and nano-TiO2 can reduce the hysteresis loop and the loss of the magnetic permeability of the magnetic core. The second auxiliary material is used to further improve the performance of the material. The addition of Ta2O5 and V2O5 can significantly reduce the loss of the material, the addition of Bi2O3 can increase the saturation magnetic induction intensity and the residual induction intensity of the material, and the addition of HfO2 can improve the anti-magnetic field stability of the material. The synergistic effect of the components in the application is to comprehensively regulate the types and contents of the main component and the auxiliary materials, so that the manganese-zinc ferrite magnetic core has the performance of wide temperature and low power consumption. The main component provides the basic performance of the manganese-zinc ferrite, the first auxiliary material further improves the performance of the material by regulating the growth of the crystal grains, reducing the loss of the hysteresis loop and the magnetic permeability, and the addition of the second auxiliary material can modify the loss and enhance the stability of the material. Through the synergistic effect, the magnetic core can have low power consumption in a wide temperature range, and the requirements of high inductance, high energy conversion rate and wide temperature use can be met.

[0009] In a second aspect, the application provides a preparation method of a wide-temperature low-power-consumption magnetic core, which adopts the following technical scheme: a preparation method of a wide-temperature low-power-consumption magnetic core, which adopts the raw material of the wide-temperature low-power-consumption magnetic core, and comprises the following steps:

[0010] S21, batching and ball milling: the main components Fe2O3, ZnO and MnO are mixed according to the formula amount, then water is added in a ball mill for mixing and ball milling, the ball milling is cycled for 30-60 min, drying is performed, then pre-sintering is performed at a temperature of 850-900℃ in an air atmosphere for 1.5-2.5 h, and a pre-sintered material is obtained;

[0011] S22, secondary ball milling: the first auxiliary material, the second auxiliary material and the pre-sintered material obtained in step S31 are mixed, secondary ball milling and drying are performed, and a ball-milled powder material is obtained;

[0012] S23, spray granulation and forming: the powder material after stirring is completed is sequentially passed through a 100-mesh sieve, then is transferred into a spray tower, and is spray granulated into particles with a size of 50-200 μm; the particles are formed into a magnetic core blank;

[0013] S24, sintering: comprising the following sintering procedures: the magnetic core blank is heated to a first temperature of 1250-1350℃, a certain oxygen is introduced during first heat preservation, is cooled to a second temperature of 300-350℃ at a first cooling rate in an oxygen partial pressure atmosphere, is second heat preserved, is finally cooled to a third temperature of 60-70℃ at a second cooling rate, and is naturally cooled to room temperature, and a wide-temperature low-power-consumption magnetic core is obtained.

[0014] By adopting the technical scheme, the preparation method in the application mainly includes the following steps: S21, batching and ball milling: the purpose of this step is to mix and ball mill the main components Fe2O3, ZnO and MnO, and to uniformly mix the powder and make the crystal grains more fine by ball milling. The addition of deionized water during ball milling helps the mixing and ball milling of the powder. S22, secondary ball milling: in this step, the first auxiliary material, the second auxiliary material and the pre-sintered material are mixed and subjected to secondary ball milling to further enhance the uniformity of the mixing of the components, thereby obtaining more stable particle size. S23, spray granulation and forming: the ball-milled powder is subjected to spray granulation, which can form the powder into granular form, making it easier to form. During the forming process, the granules are formed into a blank of the magnetic core by pressing or injection molding, etc. S24, sintering: this step is to densify the magnetic core blank by high temperature treatment and form a solid structure. Through the processes of heating, holding and cooling, the crystal grains in the material are fused and a continuous structure is formed. Sintering plays a crucial role in improving the performance of the magnetic core. Through the synergistic effect of the above steps, a magnetic core with wide temperature and low power consumption performance can be prepared. During the batching and ball milling of the main components and the first auxiliary material, the ball milling uniformly mixes the powder and the crystal grains are fine, thereby improving the physical properties of the material. The addition of the second auxiliary material further modifies the loss of the material and improves the stability of the material. During the spray granulation and forming process, granules suitable for forming are formed and a magnetic core blank is obtained, providing a good prerequisite for subsequent sintering. Sintering fuses the crystal grains of the magnetic core and forms a dense structure, thereby enabling the magnetic core to have a wide temperature and low power consumption performance. Through the synergistic effect of each step, the preparation method in the application can realize the wide temperature and low power consumption performance of the manganese-zinc ferrite, and meet the requirements of high inductance, high energy conversion rate, low power loss and wide temperature use.

[0015] Preferably, in step S21, the mass ratio of the raw materials put into the ball mill: grinding medium: water is 1:6-8:1.2-1.6, and the grinding medium uses Φ0.4-0.55mm zirconium balls.

[0016] Preferably, in step S22, the secondary sand milling time is 2-3h; and the particle size D50 of the ball-milled powder is 0.8-1.0μm.

[0017] Preferably, in step S23, a binder is added during the spray granulation process, and the binder is a composition of polyvinyl alcohol and zinc stearate in a mass ratio of 5:1-3.

[0018] Preferably, the binder solution concentration is 6-8wt%, and the binder is 8-10% of the sieved powder of the ball-milled powder.

[0019] By adopting the above technical scheme, in step S23, the function of adding the binder in the spray granulation process is to agglomerate the powder into particles, and help to form the magnetic core blank. The composition of the binder is polyvinyl alcohol and zinc stearate, which can provide sufficient binding force and plasticity, so that the powder forms particles in the spray granulation process, and maintains the shape in the subsequent forming process. The solution concentration of the binder is 6-8wt%, by controlling the concentration, it can ensure that the solution has appropriate viscosity and fluidity, which is convenient for the process of spray granulation. The addition amount of the binder is 8-10% of the sieved ball milled powder, by controlling the addition amount of the binder, the powder can obtain sufficient binding force, so as to form a relatively stable particle structure. The addition of the binder in step S23 can make the powder more easily form particles, and maintain the stability of the particle shape, thereby providing good conditions for the subsequent forming process. The addition of the binder can also help to improve the density and strength of the particles in the spray granulation process, thereby improving the physical properties of the final magnetic core.

[0020] Preferably, in step S23, the pressure of the forming is 80-150MPa, and the time is 30-100s.

[0021] Preferably, in step S24, the heating rate of the heating is 2-3℃ / min, and the holding time of the first temperature is 3-6h.

[0022] Preferably, in step S24, the first cooling rate is 1.5-2℃ / min, the holding time of the second temperature is 5-8h, and the second cooling rate is 0.2-0.4℃ / min.

[0023] Preferably, in step S24, the oxygen content in the equilibrium oxygen partial pressure atmosphere is 1.8-2.3vol%.

[0024] By adopting the technical scheme, in step S24, when the magnetic core blank is sintered, a certain oxygen is introduced under the atmosphere of balanced oxygen partial pressure, and the oxygen content is 1.8-2.3 vol%. The presence and control of the balanced oxygen partial pressure in this step are very important, and are coordinated with other steps to realize the preparation of the wide-temperature low-power-consumption magnetic core. In the sintering process, the presence of the balanced oxygen partial pressure can affect the magnetic properties and electrical properties of the magnetic core. The appropriate oxygen content can control the crystal structure and magnetic properties of the magnetic core, and then affect the low power loss and wide-temperature characteristics of the magnetic core. Specifically, the appropriate oxygen content helps to form an ideal magnetic grain structure, improve the saturation magnetization and coercivity of the magnetic core, and thus improve the inductance and energy conversion rate of the magnetic core. In addition, controlling the oxygen content can also effectively regulate the magnetic hysteresis loss of the magnetic core, so that the magnetic core can maintain a low power loss in each temperature range. By controlling the oxygen content in the balanced oxygen partial pressure atmosphere, the regulation of the grain structure and magnetic properties of the magnetic core can be realized in the sintering process, thereby realizing the requirements of the wide-temperature low-power-consumption magnetic core.

[0025] In summary, the beneficial technical effects of the present application are:

[0026] 1. The addition range of the main components and the first auxiliary material is controlled, and the manganese-zinc ferrite has the performance of wide-temperature low-power-consumption. By mixing Fe2O3, ZnO and MnO and other main components, a magnetic core material with good wide-temperature characteristics can be obtained.

[0027] 2. The second auxiliary material is added to modify the loss, so that there is a low power loss at each temperature. By mixing the first auxiliary material, the second auxiliary material and the pre-fired material, the loss of the magnetic core can be adjusted to achieve the effect of low power consumption.

[0028] 3. The application range under extreme conditions is solved. The preparation method can maintain the wide-temperature low-power-consumption performance of the magnetic core under extreme temperature conditions, so that the magnetic core can still work normally in a high-temperature or low-temperature environment, thereby expanding the application range of the magnetic core.

[0029] 4. The requirements of high inductance, high energy conversion rate, low power loss and wide-temperature use of the wide-temperature low-power-consumption magnetic core are met. The magnetic core obtained by the preparation method has high inductance and energy conversion rate, and at the same time has low power loss, and can work stably in a wide temperature range. DETAILED DESCRIPTION

[0030] The embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only for illustration of the present application and should not be regarded as limiting the scope of the present application. If the specific conditions are not specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0031] Embodiment 1

[0032] A wide-temperature low-power magnetic core, comprising a main component, a first auxiliary material and a second auxiliary material, the main component is composed of Fe2O3, ZnO and MnO in terms of mole fraction, the content is Fe2O3 52.3mol%, ZnO 7.5mol%, and the rest is MnO; the first auxiliary material comprises CaCO3, ZrO2, Nb2O, Co2O3, nano-SiO2 and nano-TiO2; the content of each auxiliary component in the first auxiliary material is 0.03wt% of CaCO3, 0.002wt% of ZrO2, 0.02wt% of Nb2O, 0.20wt% of Co2O3, 0.004wt% of nano-SiO2 and 0.006wt% of nano-TiO2, based on the total weight of the main component; the second auxiliary material comprises Ta2O5, V2O5, Bi2O3 and HfO2; the content of each auxiliary component in the second auxiliary material is 0.03wt% of Ta2O5, 0.06wt% of V2O5, 0.05wt% of Bi2O3 and 0.01wt% of HfO2, based on the total weight of the main component; the particle size of the nano-SiO2 is 20-40nm, and the particle size of the nano-TiO2 is 40-80nm.

[0033] A preparation method of a wide-temperature low-power magnetic core, using the raw materials of the wide-temperature low-power magnetic core described above, comprising the following steps:

[0034] S21, batching and ball milling: mixing the main components Fe2O3, ZnO and MnO according to the formula amount, then adding water in a ball mill for mixing and ball milling, the mass ratio of the raw materials put into the ball mill: grinding medium: water is 1:6:1.2, the grinding medium uses Φ0.4-0.55mm zirconium balls, the cycle ball milling time is 30min, drying, then pre-burning at 850℃ in air atmosphere for 2.5h to obtain pre-burned material;

[0035] S22, secondary ball milling: mixing the first auxiliary material, the second auxiliary material and the pre-burned material obtained in step S31, then secondary ball milling and drying to obtain a ball milled powder, the secondary sand milling time is 2h, and the particle size D50 of the ball milled powder is 0.8-1.0μm;

[0036] S23, spray granulation and forming: the powder after stirring is transferred into a spray tower after passing through a 100-mesh sieve in sequence, and is spray granulated into particles of 50-200 μm; a binder is added in the process of spray granulation, the binder is a composition of polyvinyl alcohol and zinc stearate in a mass ratio of 5:1, the binder solution concentration is 6 wt%, the binder is 8% of the powder after ball milling and sieving, the particles are formed into a magnetic core blank, the forming pressure is 80 MPa, and the time is 100 s; S24, sintering: including the following sintering procedures: the magnetic core blank is heated to a first temperature of 1250℃ at a heating rate of 2℃ / min, a certain oxygen is introduced when the first temperature is kept for 6 h, the oxygen content is 1.8 vol% in the equilibrium oxygen partial pressure atmosphere, the temperature is lowered to a second temperature of 300℃ at a first cooling rate of 1.5℃ / min, the second temperature is kept for 8 h, finally the temperature is lowered to a third temperature of 60℃ at a second cooling rate of 0.2℃ / min, and then the temperature is naturally cooled to room temperature, to obtain a wide-temperature low-power magnetic core.

[0037] Example 2

[0038] A wide-temperature low-power magnetic core, comprising a main component, a first auxiliary material and a second auxiliary material, the main component is composed of Fe2O3, ZnO and MnO in terms of mole fraction, the content is Fe2O3 52.9 mol%, ZnO 8.2 mol%, and the rest is MnO; the first auxiliary material comprises CaCO3, ZrO2, Nb2O, Co2O3, nano-SiO2 and nano-TiO2; the content of each auxiliary component in the total weight of the main component is CaCO3 0.05 wt%, ZrO2 0.005 wt%, Nb2O 0.03 wt%, Co2O3 0.26 wt%, nano-SiO2 0.007 wt% and nano-TiO2 0.009 wt%; the second auxiliary material comprises Ta2O5, V2O5, Bi2O3 and HfO2; the content of each auxiliary component in the total weight of the main component is Ta2O5 0.05 wt%, V2O5 0.09 wt%, Bi2O3 0.08 wt% and HfO2 0.04 wt%, the particle size of the nano-SiO2 is 20-40 nm, and the particle size of the nano-TiO2 is 40-80 nm.

[0039] A preparation method of a wide-temperature low-power magnetic core, using the raw materials of the above wide-temperature low-power magnetic core, comprising the following steps:

[0040] S21, batching and ball milling: the main ingredients Fe2O3, ZnO and MnO are mixed according to the formula, and then water is added in a ball mill for mixing and ball milling, the mass ratio of the raw materials put into the ball mill: grinding medium: water is 1:8:1.6, the grinding medium uses Φ0.4-0.55mm zirconium ball, the cycle ball milling is 60min, drying, and then pre-burning at 900℃ in air atmosphere for 1.5h to obtain pre-burned material;

[0041] S22, secondary ball milling: the first auxiliary material, the second auxiliary material and the pre-burned material obtained in step S31 are mixed, and then secondary ball milling and drying are performed to obtain a ball milled powder, the secondary sand milling time is 3h, and the particle size D50 of the ball milled powder is 0.8-1.0μm;

[0042] S23, spray granulation and forming: after the stirring is completed, the powder is sequentially passed through a 100 mesh sieve, and then transferred into a spray tower for spray granulation into 50-200μm particles; a binder is added during the spray granulation, the binder is a composition of polyvinyl alcohol and zinc stearate in a mass ratio of 5:3, the binder solution concentration is 8wt%, the binder is 10% of the sieved ball milled powder, the particles are formed into a magnetic core blank, the forming pressure is 150MPa, and the time is 30s; S24, sintering: including the following sintering process: the magnetic core blank is heated to a first temperature of 1350℃ at a heating rate of 3℃ / min, a certain oxygen is introduced during the first holding for 3h, the oxygen content is 2.3vol% under the equilibrium oxygen partial pressure atmosphere, the temperature is lowered to a second temperature of 350℃ at a first cooling rate of 2℃ / min, the second holding is 3h, finally the temperature is lowered to a third temperature of 70℃ at a second cooling rate of 0.4℃ / min, and then naturally cooled to room temperature to obtain a wide temperature low-power magnetic core.

[0043] Example 3

[0044] A wide temperature low power consumption magnetic core, comprising a main component, a first auxiliary material and a second auxiliary material, the main component is composed of Fe2O3, ZnO and MnO in terms of mole fraction, the content is Fe2O3 52.6mol%, ZnO 7.9mol%, and the rest is MnO; the first auxiliary material comprises CaCO3, ZrO2, Nb2O, Co2O3, nano SiO2 and nano TiO2; the content of each auxiliary component of the first auxiliary material is 0.04wt% of CaCO3, 0.004wt% of ZrO2, 0.025wt% of Nb2O, 0.23wt% of Co2O3, 0.006wt% of nano SiO2 and 0.007wt% of nano TiO2, based on the total weight of the main component; the second auxiliary material comprises Ta2O5, V2O5, Bi2O3 and HfO2; the content of each auxiliary component of the second auxiliary material is 0.04wt% of Ta2O5, 0.07wt% of V2O5, 0.07wt% of Bi2O3 and 0.03wt% of HfO2, based on the total weight of the main component, the particle size of the nano SiO2 is 20-40nm, and the particle size of the nano TiO2 is 40-80nm.

[0045] A preparation method of a wide temperature low power consumption magnetic core, using the raw material of the wide temperature low power consumption magnetic core, comprising the following steps:

[0046] S21, batching and ball milling: the main ingredients Fe2O3, ZnO and MnO are mixed according to the formula, then water is added in a ball mill for mixing and ball milling, the mass ratio of the raw materials put into the ball mill: grinding medium: water is 1:7:1.4, the grinding medium uses Φ0.4-0.55mm zirconium balls, the cycle ball milling time is 45min, drying, then pre-sintering at a temperature of 880℃ in an air atmosphere for 2h, to obtain a pre-sintered material; S22, secondary ball milling: mixing the first auxiliary material, the second auxiliary material and the pre-sintered material obtained in step S31, to obtain a ball milled powder after secondary ball milling and drying, the secondary ball milling time is 2.5h, the particle size D50 of the ball milled powder is 0.8-1.0μm; S23, spray granulation and forming: the powder after stirring is completed is transferred into a spray tower in turn after passing through a 100 mesh sieve, and is spray granulated into particles with a size of 50-200μm; a binder is added in the process of spray granulation, the binder is a composition of polyvinyl alcohol and zinc stearate with a mass ratio of 5:2, the binder solution concentration is 7wt%, the binder is 9% of the powder after the ball milled powder is sieved, the particles are formed into a magnetic core blank, the forming pressure is 120MPa, and the time is 70s; S24, sintering: including the following sintering procedures: the magnetic core blank is heated to a first temperature of 1300℃ at a heating rate of 2.5℃ / min, a certain oxygen is introduced when the first temperature is kept for 4h, the oxygen content is 2vol% in the equilibrium oxygen partial pressure atmosphere, the temperature is lowered to a second temperature of 330℃ at a first cooling rate of 1.8℃ / min, the second temperature is kept for 7h, finally the temperature is lowered to a third temperature of 65℃ at a second cooling rate of 0.3℃ / min, and then the temperature is naturally cooled to room temperature, to obtain a wide temperature low-power magnetic core.

[0047] Comparative Example 1

[0048] The same as Example 3, except that the content of ZnO is changed to ZnO 7.0mol%.

[0049] Comparative Example 2

[0050] The same as Example 3, except that the content of nano-TiO2 is changed to 0, i.e. no TiO2 is added.

[0051] Comparative Example 3

[0052] The same as Example 3, except that the content of nano-TiO2 is changed to 0.015wt%.

[0053] Comparative Example 4

[0054] The same as Example 3, except that the content of Ta2O5 is changed to 0, i.e. no Ta2O5 is added.

[0055] Comparative Example 5

[0056] The same as example 3, except that the content of Ta2O5 is changed to 0.08wt%.

[0057] Comparative example 6

[0058] The same as example 3, except that the content of V2O5 is changed to 0, i.e. no V2O5 is added.

[0059] Comparative example 7

[0060] The same as example 3, except that the content of V2O5 is changed to 0.13wt%.

[0061] Comparative example 8

[0062] The same as example 3, except that the oxygen content in the equilibrium oxygen partial pressure atmosphere is changed to 1.4vol%.

[0063] Comparative example 9

[0064] The same as example 3, except that an equal amount and concentration of polyvinyl alcohol is used instead of the binder being a composition of polyvinyl alcohol, zinc stearate in a mass ratio of 5:2.

[0065] Comparative example 10

[0066] The same as example 3, except that an equal amount and concentration of zinc stearate is used instead of the binder being a composition of polyvinyl alcohol, zinc stearate in a mass ratio of 5:2.

[0067] Performance test

[0068] The performance of the wide temperature low power consumption magnetic core prepared in example 1, example 3 and comparative examples 1-10 was detected, and the specific detection method was as follows: according to the standard SJ20966-2006 soft magnetic ferrite material measurement method, an IWATSUB-H analyzer (SY-8219) was used, and the results are shown in table 1.

[0069] Table 1

[0070]

[0071] From Table 1, it can be seen that the wide-temperature low-power-consumption magnetic cores prepared in Examples 1-3 effectively reduce the loss of the wide-temperature low-power-consumption magnetic cores at-40-150℃ by controlling the content of ZnO, TiO2, Ta2O5, V2O5, the type and amount of the binder, and the oxygen content of the sintering process, and have the advantages of wide temperature range and low power consumption. The wide-temperature low-power-consumption magnetic cores of the application basically achieve the performance of wide-temperature low-power-consumption of manganese-zinc ferrite by controlling the addition range of the main component and the first auxiliary material, and add the second auxiliary material to modify the loss, so that there is a lower power loss at each temperature, which can greatly solve the application range of the wide-temperature low-power-consumption magnetic cores under extreme conditions, meet the requirements of high inductance, high energy conversion rate, low power loss and wide temperature use of the wide-temperature low-power-consumption magnetic cores, and have great application potential.

[0072] From Table 1, it can be seen that the performance of the wide-temperature low-power-consumption magnetic cores obtained in Example 3 and Comparative Example 1 is compared and analyzed, and the loss is high when the content of ZnO is too low.

[0073] From Table 1, it can be seen that the performance of the wide-temperature low-power-consumption magnetic cores obtained in Example 3 and Comparative Examples 2-3 is compared and analyzed, and the loss trend is not smooth and the loss is high when the content of TiO2 is too low or too high.

[0074] From Table 1, it can be seen that the performance of the wide-temperature low-power-consumption magnetic cores obtained in Example 3 and Comparative Examples 4-5 is compared and analyzed, and the loss is significantly affected when the content of Ta2O5 is too low or too high.

[0075] From Table 1, it can be seen that the performance of the wide-temperature low-power-consumption magnetic cores obtained in Example 3 and Comparative Examples 6-7 is compared and analyzed, and the loss is significantly affected when the content of V2O5 is too low or too high.

[0076] From Table 1, it can be seen that the performance of the wide-temperature low-power-consumption magnetic cores obtained in Example 3 and Comparative Example 8 is compared and analyzed, and the loss is high due to the low oxygen content.

[0077] From Table 1, it can be seen that the performance of the wide-temperature low-power-consumption magnetic cores obtained in Example 3 and Comparative Examples 9-10 is compared and analyzed, and the performance of the wide-temperature low-power-consumption magnetic cores obtained by using the binder as polyvinyl alcohol and zinc stearate in a mass ratio of 5:2 is better.

[0078] The above examples are only used to explain the technical solutions of the application and not to limit them, although the above examples have been specifically described, relevant technical personnel should understand that the specific embodiments of the application can still be modified or replaced by equivalents without departing from the spirit and scope of the application, any modification and equivalent replacement thereof should be covered in the protection scope of the application.

Claims

1. A wide temperature low power consumption magnetic core, characterized by, The application relates to a wide-temperature low-power-consumption magnetic core, which comprises a main component, a first auxiliary material and a second auxiliary material, wherein the main component is composed of Fe2O3, ZnO and MnO in terms of molar fraction, and the content of Fe2O3 is 52.3-52.9 mol%, the content of ZnO is 7.5-8.2 mol%, and the rest is MnO; the first auxiliary material comprises CaCO3, ZrO2, Nb2O5, Co2O3, nano-SiO2 and nano-TiO2; the content of each auxiliary material component in the first auxiliary material is 0.03-0.05 wt% of CaCO3, 0.002-0.005 wt% of ZrO2, 0.02-0.03 wt% of Nb2O5, 0.20-0.26 wt% of Co2O3, 0.004-0.007 wt% of nano-SiO2 and 0.006-0.009 wt% of nano-TiO2, based on the total weight of the main component; the second auxiliary material comprises Ta2O5, V2O5, Bi2O3 and HfO2; the content of each auxiliary material component in the second auxiliary material is 0.03-0.05 wt% of Ta2O5, 0.06-0.09 wt% of V2O5, 0.05-0.08 wt% of Bi2O3 and 0.01-0.04 wt% of HfO2, based on the total weight of the main component; the particle size of the nano-SiO2 is 20-40 nm; and the particle size of the nano-TiO2 is 40-80 nm. The preparation method of the wide-temperature low-power-consumption magnetic core comprises the following steps: S21, dosing and ball milling: the main components Fe2O3, ZnO and MnO are mixed according to the formula amount, then water is added in a ball mill for mixing and ball milling, the ball milling is cycled for 30-60 min, drying is conducted, then pre-sintering is conducted at a temperature of 850-900 DEG C under an air atmosphere for 1.5-2.5 h, and pre-sintered material is obtained; S22, secondary ball milling: the first auxiliary material, the second auxiliary material and the pre-sintered material obtained in the step S21 are mixed, secondary ball milling and drying are conducted, and ball milled powder material is obtained; S23, spray granulation and forming: the powder material after stirring is completed is sequentially passed through a 100-mesh sieve, then is transferred into a spray tower, and is spray granulated into particles with a size of 50-200 mu m; and the particles are formed into a magnetic core blank; S24, sintering: the sintering process comprises the following steps: the magnetic core blank is heated to a first temperature of 1250-1350 DEG C, oxygen is introduced during first temperature maintaining, the temperature is lowered to a second temperature of 300-350 DEG C at a first temperature lowering rate under an oxygen partial pressure atmosphere, second temperature maintaining is conducted, finally the temperature is lowered to a third temperature of 60-70 DEG C at a second temperature lowering rate, and natural cooling is conducted to room temperature, and a wide-temperature low-power-consumption magnetic core is obtained; the oxygen content in the oxygen partial pressure atmosphere is 1.8-2.3 vol%; In the step S23, a binder is added in the process of spray granulation, the binder is a composition of polyvinyl alcohol and zinc stearate with a mass ratio of 5:1-3; the binder concentration is 6-8 wt%; and the binder is 8-10% of the powder after the ball milled powder is sieved.

2. The wide temperature low power consumption magnetic core of claim 1, wherein, In step S21, the mass ratio of raw material: grinding medium: water put into the ball mill is 1:6-8:1.2-1.6, the grinding medium uses zirconium ball with Φ0.4-0.55mm.

3. The wide temperature low power consumption magnetic core of claim 1, wherein, In step S22, the time of the secondary ball milling is 2-3h; the particle size D50 of the ball-milled powder is 0.8-1.0μm.

4. The wide temperature low power consumption magnetic core of claim 1, wherein, In step S23, the pressure of the molding is 80-150MPa, and the time is 30-100s.

5. The wide temperature low power consumption magnetic core of claim 1, wherein, In step S24, the heating rate of the temperature rising is 2-3℃ / min, and the holding time at the first temperature is 3-6h.

6. The wide temperature low power consumption magnetic core of claim 1, wherein, In step S24, the first cooling rate is 1.5-2℃ / min, the holding time at the second temperature is 5-8h, and the second cooling rate is 0.2-0.4℃ / min.

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