66 results about "Initial permeability" patented technology

The invention relates to the technical field of magnetic material preparation and heat treatment, in particular to a heat treatment process window widening method for a high-magnetic-conductivity nanocrystalline strip, which comprises the following steps of: by gradient component design and pulsed magnetic field coupling heat treatment, enabling the initial magnetic conductivity of the strip to exceed 22,000 and widening the heat treatment temperature interval to 400-600 DEG C; the alloy comprises 73.5% of Fe, 1% of Cu, 3% of Nb, 13.5% of Si, 8.5% of B and 0.5% of Co, during heat treatment, the temperature is increased to 450 DEG C at the speed of 15 DEG C / min, a 0.8 T pulsed magnetic field is applied for heat preservation, then the temperature is increased to 550 DEG C for heat preservation, alpha-Fe (Si) nanocrystalline and Co-B amorphous interface phases are generated through crystallization, and Co is distributed in a solid solution mode. The method widens the heat treatment temperature interval, improves the initial magnetic conductivity of the strip, improves the toughness, meets automatic production, and reduces the cost by using the existing equipment; and the prepared strip is high in magnetic conductivity, good in stability, suitable for various scenes and good in economic benefit and social benefit.

The invention relates to a manganese zinc ferrite material and a preparation method thereof, the manganese zinc ferrite material comprises main components and auxiliary components, the main components comprise Fe2O3, ZnO and MnO, and the auxiliary components comprise CoO, CaO, Bi2O3 and MoO; and in the main components, the content of Fe2O3 is 52.0 to 53.0 mol percent, the content of ZnO is 18.0 to 19.0 mol percent, and the content of MnO is 28.0 to 30.5 mol percent in terms of mole percent. According to the manganese-zinc ferrite material, the initial permeability mu i is greater than or equal to 12000 in a wide temperature range of 0-145 DEG C, and the manganese-zinc ferrite material has a relatively low temperature coefficient in the temperature range; the magnetic conductivity does not drop under the high frequency of 300kHz, and mu i is greater than or equal to 9000; the Curie temperature Tc is greater than 145 DEG C, so that the stability of the manganese-zinc ferrite material applied to the field of automotive electronics or a conventional anti-EMI common-mode filter is greatly improved.

The present application provides a susceptor for inductively heating an aerosol generating substrate, a preparation method of the susceptor, and an aerosol generating article comprising the susceptor; the susceptor comprises a single alloy prepared by smelting iron, nickel and zircon as main element raw materials, has a Curie temperature of 300-600 DEG C, and the initial magnetic permeability of the alloy presents a peak characteristic with the increase of temperature. The single layer structure susceptor of the single alloy material of the present application realizes the functions of heating and temperature control at the same time, and overcomes the defects of the prior art, such as complex process, high preparation cost, and limited compatibility of electromagnetic induction heating appliances. Meanwhile, the susceptor has a relatively wide magnetic performance variation window and an aerosol generating system performance variation window, and can be flexibly adapted to more aerosol generating substrates.

The invention provides a method for testing the initial permeability of a soft magnetic material. The method comprises the following steps: arranging a protection box for a sample; confirming the number of turns of the magnetizing coil; confirming the number of turns of the induction coil; uniformly winding an induction coil and a magnetizing coil outside the protection box; inputting current to the magnetizing coil through test equipment, and calculating the test magnetic conductivity mu test of the test sample based on the magnetic flux of the induction coil and the sectional area S sample of the sample; and calculating the initial permeability [mu] real of the sample according to the test permeability [mu] test of the sample, the permeability [mu] box of the protection box, the sectional area S box of the protection box, the permeability [mu] gas of the air gap between the protection box and the sample, and the sectional area S gas of the air gap.

The present invention relates to the field of magnetic material preparation and heat treatment technology, specifically a method for widening the heat treatment process window of a high magnetic permeability nanocrystalline strip. By gradient composition design and pulsed magnetic field coupling heat treatment, the initial magnetic permeability of the strip exceeds 220,000 and the heat treatment temperature range is widened to 400°C-600°C; the alloy composition is Fe73.5%, Cu1%, Nb3%, Si13.5%, B8.5%, Co0.5%, and during heat treatment, the temperature is first raised to 450°C at 15°C / min and a 0.8T pulsed magnetic field is applied to keep the temperature, and then the temperature is raised to 550°C for keeping the temperature, crystallizing to generate α-Fe(Si) nanocrystals and Co-B amorphous interface phase, with Co distributed in the form of solid solution. This method widens the heat treatment temperature range, improves the initial magnetic permeability of the strip, improves toughness to meet automated production, and reduces costs using existing equipment; the prepared strip has high magnetic permeability and good stability, is suitable for a variety of scenarios, and has good economic and social benefits.

The invention discloses magnetically soft alloy powder and a preparation method and application thereof, and relates to the technical field of magnetic materials. The specific preparation method comprises the following steps: firstly, in an inert atmosphere, mixing, heating and smelting various raw materials into an alloy, continuously heating to obtain mixed steam, condensing the mixed steam, and collecting to obtain alloy powder; and then organic silicon resin is used as an insulating material, the insulating material is added into a solvent, then the alloy powder is added and evenly mixed, and finally the magnetically soft alloy powder is obtained through drying. The method is simple in process and short in production period, and a soft magnetic core made of the soft magnetic alloy powder prepared through the method has the advantages of being high in initial permeability and low in magnetic core loss.

The utility model relates to a zero sequence current transformer applied in the electrical field, which comprises an iron core made of ferromagnetic material with high initial permeability, a secondary winding is wound on the iron core, the outer side of the secondary winding is coated with a magnetic shielding layer, and the initial permeability of the ferromagnetic material in the magnetic shielding layer is higher than that of the iron core; the secondary winding is equally divided into a plurality of parts and then connected in series end to end, the output end of the secondary winding is connected with a plurality of divider resistors in series, each divider resistor is provided with a plurality of taps, and voltage output by each tap is subjected to data acquisition according to needs. And a voltage signal output by the tap with the highest amplitude but not exceeding a limit value is used as a standard basis. According to the utility model, main magnetic flux and leakage magnetic flux generated by primary current and secondary current of each phase are the same as much as possible, and unbalanced output is minimized.

The invention relates to a zero sequence current transformer applied in the electrical field, which comprises an iron core made of a ferromagnetic material with high initial permeability, a secondary winding is wound on the iron core, the outer side of the secondary winding is coated with a magnetic shielding layer, and the initial permeability of the ferromagnetic material in the magnetic shielding layer is higher than that of the iron core; the secondary winding is equally divided into a plurality of parts and then connected in series end to end, the output end of the secondary winding is connected with a plurality of divider resistors in series, each divider resistor is provided with a plurality of taps, and voltage output by each tap is subjected to data acquisition according to needs. And a voltage signal output by the tap with the highest amplitude but not exceeding a limit value is used as a standard basis. According to the invention, main magnetic flux and leakage magnetic flux generated by primary current and secondary current of each phase are the same as much as possible, and unbalanced output is minimized.

The present invention discloses a high-reliability, heat-shock-resistant, wide-temperature, low-loss ferrite and its preparation method and application, belonging to the technical field of magnetic materials. The present invention introduces a fourth main component NiO on the basis of the main formula of Fe2O3, ZnO and MnO to form a quaternary ferrite, thereby producing a uniform second phase and achieving a self-toughening effect; by introducing CaCO3, V2O5, Nb2O5, Co3O4, ZrO2 and Na2SiO3 as auxiliary components, the toughness of the ferrite is further improved. The high-reliability, heat-shock-resistant, wide-temperature, low-loss ferrite provided by the present invention has a power consumption of ≤350mW / cm at 25°C under the conditions of 100kHz and 200mT. 3 , 100℃ power consumption ≤350mW / cm 3 The initial magnetic permeability is 3100. Compared with existing magnetic materials, it has the characteristics of wide temperature and low power consumption, and can withstand temperature cycle shocks from ‑40°C to 150°C for more than 1,000 times.

The application provides a manganese-zinc ferrite material and a preparation method and application thereof. The manganese-zinc ferrite material can have an initial permeability μi of 1837 H / m or higher, a saturation magnetic induction intensity Bs of 572 mT or higher at 25 DEG C, and a saturation magnetic induction intensity Bs of 487 mT or higher at 100 DEG C through specific setting of a formula, so that the power conversion efficiency of an electronic component is improved.

The embodiment of the invention discloses a method for acquiring frequency-dependent inductance parameters of a transformer and related equipment, and the method comprises the steps: constructing a homogenized iron core model of the transformer, and obtaining the initial permeability of the homogenized iron core model in different directions; optimizing the initial magnetic conductivities in different directions by using the thickness and conductivity of the silicon steel sheet, the magnetic field angular frequency of the transformer and the proportionality coefficient of the silicon steel sheet and the insulating coating in the iron core lamination direction to obtain the optimized magnetic conductivities in different directions; and obtaining inductance parameter values of the transformer at different frequencies by utilizing the optimized magnetic permeability in different directions at different frequencies and a preset static magnetic field solver. The thickness and conductivity of the silicon steel sheet, the magnetic field angular frequency of the transformer and the proportionality coefficient of the silicon steel sheet and the insulating coating in the iron core lamination direction are used for optimizing the initial magnetic conductivity in different directions, the magnetic conductance performance of the iron core can be effectively reflected, and therefore the precision of the obtained inductance parameter value is improved.

To provide soft magnetic metal particles that can provide a powder magnetic core having a high initial permeability μi.SOLUTION: A soft magnetic metal particle includes a core particle and an insulating film formed on the surface of the core particle. The insulating film has a first layer, a second layer, and a third layer. The first layer is in contact with the surface of the core particle, and the second layer is in contact with the first layer and the third layer. The first layer contains at least Fe, the second layer contains at least Ti, and the third layer contains at least Si.SELECTED DRAWING: Figure 1

The application discloses a kind of high-power radio frequency magnetron sputtering patterning preparation CoTaZr film and high-frequency performance regulation process, belongs to soft magnetic film preparation technical field.The application is with high-power radio frequency magnetron sputtering as core deposition process, stripe pattern is as characteristic regulation means, and the composition ratio of preparation patterned CoTaZr amorphous soft magnetic film is Co:89 at.%;Ta:5 at.%;Zr:6 at.% on Si (111) substrate;By 140W high sputtering power optimization film intrinsic structure and morphology, in combination with the mask plate induced shape anisotropy that stripe spacing is fixed at 50 μm, width 30 μm~70 μm, realize the synergic regulation of film high-frequency performance, surface morphology and resistivity.The application is carried out at room temperature, and compatible with standard CMOS process, the film cutoff frequency is continuously regulated at 2.19~3.06 GHz, saturation magnetization is stable at 12000~12500 Gs, initial permeability is 191~371 adjustable, surface roughness is 0.401~1.284 nm, resistivity keeps low loss characteristics, solve the problem that film morphology, resistivity and high-frequency performance are difficult to take into account in traditional process, can meet the application demand of GHz frequency band on-chip integrated inductor, 5G communication module and other high-frequency devices on magnetic core material.

The invention discloses a preparation method of a wide-range current transformer iron core, which comprises the following steps of: selecting a first ferromagnetic material strip with initial permeability mu i greater than 50,000 and a second ferromagnetic material strip with saturation flux density Bs greater than 1.8 T, the thickness of the first material being 15-30 microns, and the thickness of the second material being 0.10-0.30 mm; the strip is precisely cut, and the dimensional tolerance is controlled within + / -0.02 mm; the cut strip is subjected to surface insulation treatment, and an insulation coating of 1-3 microns is formed on the surface of the second material; the two materials are combined into an annular iron core in an alternate lamination mode, and an insulating layer smaller than 5 microns is arranged between layers; and carrying out multi-stage annealing treatment in a protective atmosphere, wherein the multi-stage annealing treatment comprises a 300-450 DEG C destressing stage, a recrystallization stage and a 400-500 DEG C magnetic field annealing stage. According to the iron core manufactured by the method, the ratio error is less than 0.5% and the angular difference is less than 20 minutes within the rated current range of 0.1-200%, so that wide-range and high-precision measurement is realized, and a reliable technical basis is provided for accurate measurement of a power system.

The invention discloses a preparation method for improving the initial permeability of permalloy, which is based on Fe-Ni-Mo permalloy and adopts a ternary synergistic process of electron beam smelting, ultra-large cold rolling deformation and magnetic field heat treatment. The permalloy strip with the ultrahigh initial permeability is prepared through the method, three microscopic barriers including an impurity pinning barrier, a grain boundary and defect barrier and an intrinsic magnetic barrier which limit the magnetic performance of permalloy are overcome, the permalloy strip with the ultrahigh initial permeability is obtained, and the method has the advantages of being simple in process, low in cost, easy to produce in batches and the like, and can well meet the requirements of high-end electromagnetic elements.

In the present invention, by using metal magnetic particles having a circularity of 0.7 or more in an inductor, initial permeability can be improved and DC superposition characteristics can be improved.　This inductor comprises: a coil conductor including a winding part around which a conductive wire is wound and a pair of lead-out parts led out from the winding part; an element body that contains metal magnetic particles and a resin and includes the coil conductor; and an external electrode formed on the surface of the element body and connected to the lead-out part of the coil conductor. The metal magnetic particles have a circularity of 0.7 or more. The metal magnetic particles having no more than a 20° adjacent angle, which is formed by a line between adjacent metal magnetic particles and a line in the thickness direction of the element body, are present at an accumulation frequency of 20% or more in a portion of the element body surrounded by the winding part of the coil conductor.

The application discloses a DC superimposition-resistant and wide-temperature low-loss MnZn ferrite and a preparation method and application thereof. The MnZn ferrite main material is prepared according to the required raw material weight of 52.3-53.3 mol% of Fe2O3, 35.2-36.2 mol% of MnO, 0.12-0.18 mol% of TiO2 and the balance of ZnO; the additive is prepared by mixing 0.12-0.16 wt% of CaCO3, 0.02-0.04 wt% of SiO2, 0.03-0.04 wt% of V2O5, 0.12-0.18 wt% of Co2O3 and 0.1-0.3 wt% of SrTiO3 nano powder; the main material is put into a ball mill for primary ball milling mixing, and then is dried and pre-sintered; the pre-sintered powder and the additive are simultaneously put into the ball mill for secondary ball milling, and then are dried and granulated, and are formed into annular green bodies, and the ferrite is obtained by sintering the annular green bodies. The MnZn ferrite material with high DC superimposition resistance and low loss can be prepared, the initial permeability is 2933, the DC superimposition magnetic field value corresponding to a 70% reduction of the permeability is 200 A / m, the loss is lower than 330 kW / m μ70 at 100 kHz and 200 mT in the range of 25-100 DEG C. 3 ​

This invention discloses a low-temperature sintering NiCuZn ferrite material with high initial permeability and low power loss, and its preparation method. It belongs to the technical field of ferrite material preparation for LTCF inductors, and includes a main component and additives. The main component has the molecular formula Ni. 0.23‑x Cu 0.22+ x Zn 0.55 Fe2O4, x=0.01~0.04; based on the mass of the main component, the additives include: 0.4~0.9 wt% V2O5, 0.1~0.3 wt% Sb2O3. This invention employs a combined V2O5-Sb2O3 additive, whose synergistic effect provides more liquid-phase sintering sites for the liquid-phase sintering process, promotes sintering densification, and improves various magnetic properties of NiCuZn ferrite, achieving comprehensive optimization of permeability, saturation magnetic induction, and power loss at MHz-level frequencies.

The present invention discloses an optimization design method for an inductive magnetic sensor. First, the quality, length, and target noise level of the design requirements are proposed, and then the noise of the inductive magnetic sensor is systematically analyzed. According to the quality factor, the quality of the magnetic core and the winding is allocated. Then, according to the aspect ratio m of the magnetic core and the initial magnetic permeability μ of the magnetic core material r , the magnetic core is optimized in design. Finally, the winding is optimized in design to obtain the optimal wire diameter #imgabs0# and the optimal number of coil turns n opt . Ultimately, the optimal design scheme of the inductive magnetic sensor in the theoretical case is obtained. This method deeply and systematically analyzes the noise of the inductive magnetic sensor, establishes a mathematical model from two perspectives of the sensor magnetic core design and the coil design, numerically calculates various parameters required for the design, and uses the calculation results to manufacture the inductive magnetic sensor. The calculation process of this optimization design method is simple, greatly shortening the development time and reducing the R & D cost, and having good practicability.

The invention discloses a ferromagnetic material sleeve for anti-icing of an alternating-current power transmission line and a deicing method, the sleeve is of an annular split structure with an opening in the axial direction and is formed by splicing two symmetrical semi-ring pieces, the semi-ring pieces are made of iron-nickel alloy materials, and an integrated cylindrical magnetic circuit is formed after the semi-ring pieces are spliced; connecting structures are arranged on the two sides of the axial openings of the semi-ring pieces and used for achieving mutual connection between the two semi-ring pieces in the assembling process. The inner wall of each semi-ring piece is provided with a heat-conducting insulating lining which is used for achieving heat conduction and electric insulation of the sleeve to the power transmission conductor. The ferromagnetic material sleeve has extremely high initial permeability and extremely low coercive force under power frequency, strong coupling and low-loss transmission of a wire magnetic field can be achieved, and the sleeve is not saturated early and can output thermal power under large current. The sleeve can be quickly assembled on an alternating-current power transmission wire to form a closed magnetic circuit under the condition of no power failure, so that magnetic flux is converted into hysteresis heat, and the sleeve is used for preventing icing of a power transmission line.

The invention discloses a method for testing clay permeability along with temperature change, and relates to the technical field of soil body testing. According to the method, the change of the clay permeability along with the temperature is analyzed through a nuclear magnetic resonance technology, firstly, the initial permeability of a soil sample is measured and subjected to vacuum saturation, and then nuclear magnetic resonance relaxation signals are collected at different constant temperatures of 30-60 DEG C; a quantitative relation between temperature and nuclear magnetic signal intensity is established through a dry fine sand calibration experiment, and a relaxation spectrum signal is converted into water mass. And finally, calculating the permeability of the clay at different temperatures based on the fitting slope of the T2 spectrum logarithmic mean value and the temperature. According to the method, lossless quantitative evaluation of the clay permeability under the influence of the temperature is realized. According to the present invention, the fluidity of the water molecules in the cohesive soil can be determined based on the low-field nuclear magnetic resonance technology, the determination method only needs the determination of the initial permeability without the long-time penetration test after the temperature change every time, and the advantages of rapidness and high efficiency are provided.

The invention discloses a magnetic conductivity initial value prediction method for improving motor finite element analysis and calculation efficiency, and belongs to the technical field of motor design and electromagnetic field numerical calculation. The problem of improving the solving speed of a motor finite element model is solved. The method comprises the steps of establishing a stator side equivalent magnetic circuit model; establishing a rotor side magnetic field distribution prediction model for predicting air gap magnetic field distribution under different rotor topological structures; constructing a rotor side equivalent magnetic circuit model based on air-gap magnetic field distribution under different rotor topological structures predicted by a rotor side magnetic field distribution prediction model, and then solving by combining the stator side equivalent magnetic circuit model and the obtained rotor side equivalent magnetic circuit model. And obtaining magnetic conductivity approximate distribution data of a motor iron core area as an initial value, substituting the initial value into the finite element model of the motor, and carrying out iterative solution to obtain a motor electromagnetic performance analysis result. The method effectively solves the problems that in traditional finite element analysis, due to blind setting of the initial magnetic conductivity, the number of non-linear iterations is large, and calculation time is long.

According to the low-cost high-magnetic-conductivity high-magnetic-shielding magnetically soft alloy and the preparation method thereof, Fe-Si-Al is adopted as a basic system, microalloying elements such as B and Nb are creatively introduced, specific critical cold rolling and magnetic field heat treatment processes are adopted, and the obtained magnetically soft alloy has high magnetic conductivity and high magnetic shielding effectiveness. Wherein the resistivity of the alloy is effectively improved and the magnetocrystalline anisotropy is optimized through the synergistic effect of Si and Al; the grain boundary segregation effect of the B element purifies the grain boundary, and the moving resistance of the magnetic domain wall is remarkably reduced; and the dispersed precipitated phase formed by the Nb element effectively refines the initial crystal grains and lays a foundation for subsequent formation of uniform and thick recrystallized crystal grains. Particularly, a strong Gaussian texture is induced through accurately controlled critical cold rolling deformation, and magnetic domains are directionally arranged in an easy magnetization direction in combination with magnetic field heat treatment applied near a Curie point, so that the coercive force is fundamentally reduced, and the initial magnetic conductivity is improved.

The invention discloses a super-tough Fe-P-C series amorphous magnetically soft alloy ribbon and a preparation method thereof, the Fe-P-C series amorphous magnetically soft alloy ribbon comprises the components of FexPyCz, x, y and z represent the atomic percent of each element and satisfy the following conditions: 82 < x < 85, 8 < y < 12, 5 < z < 7, and x + y + z = 100. The preparation method of the super-toughness Fe-P-C series amorphous soft magnetic alloy thin strip is simple, and the material is endowed with excellent soft magnetic performance and good plasticity and toughness. Specifically, the saturation flux density of the material is 1.60-1.68 T, the coercive force of the material is 4.0-8.0 A / m, and the initial magnetic conductivity of the material is 2600-10300. Under the conditions that the magnetic flux density is 0.5 T and the magnetization frequency is 50 Hz, the iron loss range of the Fe-P-C amorphous alloy ribbon sample is 0.358-1.525 W / kg. As an amorphous soft magnetic alloy with excellent comprehensive performance, the amorphous soft magnetic alloy is expected to replace traditional silicon steel sheets and other materials in the fields of electronics, electric power and the like, and has a wide application prospect.

The invention relates to a wide-temperature, low-temperature-coefficient and high-permeability soft magnetic ferrite material, and belongs to the technical field of electronic ceramic materials. The material is composed of main components and auxiliary components, wherein the main components comprise Fe2O3, ZnO and MnO; and the auxiliary components comprise Bi2O3, MoO3, CaCO3 and CoO. The preparation method comprises the following steps: pre-sintering the main components, carrying out ball milling on the main components and the auxiliary components, granulating, carrying out compression molding, and sintering under a specific atmosphere curve. Through the magnetocrystalline anisotropy compensation effect of CoO and in combination with the co-sintering of Bi2O3 / MoO3 and the grain boundary regulation and control effect of CaCO3, the excellent comprehensive performance that the initial magnetic conductivity of the material can reach 6500 within the extremely wide temperature range of-50 DEG C to 170 DEG C, the temperature coefficient alpha F of the material is-0.5-0.5 at the temperature of-50 DEG C to 50 DEG C, and the alpha F of the material is 0-1 at the temperature of 50 DEG C to 80 DEG C is achieved synergistically.

The invention discloses manganese zinc ferrite with ultra-wide temperature width magnetic conductivity and low loss as well as a preparation method and application thereof, and belongs to the technical field of magnetic materials. By adopting the formula of more Fe2O3 and less ZnO, the magnetocrystalline anisotropy constant K1 and the saturation magnetostriction coefficient lambda s are reduced, the saturation magnetization Ms is increased, the internal and external stress of the material is reduced, an accurate and uniform microstructure is formed, and the magnetic material with high initial permeability, high saturation magnetic flux density and ultralow power consumption can be obtained; caCO3, TiO2, Nb2O5, Co3O4 and SnO2 are introduced as auxiliary components, the auxiliary components can enter crystal grains and crystal boundaries, solid-phase reaction is promoted, the sintering temperature is reduced, crystal grain growth is controlled, the ultra-wide-temperature-width magnetic conductivity of the manganese-zinc ferrite is improved, the obtained manganese-zinc ferrite with the ultra-wide-temperature-width magnetic conductivity and low loss has wide temperature and ultra-low power consumption, and the application temperature range is from-40 DEG C to 160 DEG C.

The application discloses a high-frequency low-loss composite magnetic core material and a preparation method and application thereof, and particularly relates to the technical field of soft magnetic composite materials; the composite magnetic core material is prepared from a base component and a doping component through pre-burning, pressing and sintering; the base component comprises Fe2O3, MnO and ZnO; the doping component comprises BiFeO3, SrTiO3, WO3, Co2O3, CaCO3, Nb2O5 and V2O5; the application optimizes the synergistic effect of the base component and the doping component, suppresses the loss, improves the initial magnetic permeability, realizes the balance between the high frequency and the low loss and the high magnetic permeability, and meets the high-performance requirement of high-frequency power electronic devices on the magnetic core material.

The invention provides a magnet, a preparation method thereof and electronic equipment. The magnet comprises a soft magnetic material and a hard magnetic material, the mass ratio of the soft magnetic material to the hard magnetic material is (90-99): (10-1), and the magnet has a magnetic field. By means of the magnet, on the basis that the number of turns of coils in an inductor is not increased, the magnetic core can keep high initial magnetic permeability, and meanwhile the bias characteristic of the inductor is greatly improved.

The invention discloses a high-performance ferrite core as well as a preparation method and application thereof. The preparation method comprises the following steps: weighing Fe2O3, Mn3O4, ZnO and a small amount of additives according to specific parts by mass, carrying out primary ball milling and pre-sintering, adding an ammonium polyacrylate dispersing agent in secondary ball milling, and controlling the pH value to obtain superfine slurry with D50 of 0.5-1.0 mu m; adding a polyvinyl alcohol adhesive, and carrying out spray granulation and high-pressure molding to obtain a green body; and finally, carrying out staged sintering in a controllable atmosphere, fully discharging glue at 400-600 DEG C, and carrying out heat preservation sintering at 1250-1350 DEG C under the oxygen partial pressure of 1.0-5.0%. The prepared magnetic core is uniform and fine in grain, the average size is 3-10 microns, the initial magnetic conductivity reaches 3200-3800 under 100 kHz, the saturation magnetic flux density is larger than or equal to 510 mT, and the power loss is smaller than or equal to 350 kW / m < 3 > under the conditions of 100 kHz, 200 mT and 100 DEG C. The magnetic core is suitable for a power transformer and an inductor of a 100kHz-1MHz high-frequency switching power supply, and has high magnetic conductivity, high saturation magnetic flux density and extremely low loss.

Multi-layered shielded cabin that an outer shell (2) with a first soft magnetic alloy having an initial permeability µ i1 and a maximum permeability µ max1 exhibits an inner shell (3) with a second soft magnetic alloy having an initial permeability µ i2 and a maximum permeability µ max2 exhibits, exhibits where µ i denotes the initial permeability at a control output of H=0.1 A / m, and wherein the outer shell (2) encloses the inner shell (3) and µ max1 > µ max2 and µ i2 > µ i1 .