64 results about "High saturation magnetization" patented technology

The present invention provides an iron-based nanocrystalline soft magnetic alloy powder, a soft magnetic composite material and a preparation method thereof, belonging to the technical field of soft magnetic materials. The iron-based nanocrystalline soft magnetic alloy powder has a heterogeneous nanocrystalline structure comprising a three-dimensional island-shaped amorphous region and a nanocrystalline region. The diameter of the three-dimensional island-shaped amorphous region is 50-100 nm, and the number density of the three-dimensional island-shaped amorphous region is 10 19 ‑10 20 m ‑3 The iron-based nanocrystalline soft magnetic alloy powder has the advantages of high sphericity, high saturation magnetization and low coercive force; the soft magnetic composite material comprises soft magnetic powder and a coating layer coated on the surface of the soft magnetic powder, and the coating layer comprises a binder, wherein the soft magnetic powder is the iron-based nanocrystalline soft magnetic alloy powder provided by the present invention, or is composited with at least one of iron-nickel, iron-nickel-molybdenum, iron-silicon, iron-silicon-aluminum, iron-silicon-chromium, carbonyl iron and pure iron powder, and has the advantages of low high-frequency loss, high magnetic permeability and high DC bias.

The invention provides amorphous nanocrystalline soft magnetic alloy powder, a preparation method thereof and a magnetic powder core, and relates to the technical field of soft magnetic materials. According to the preparation method of the amorphous nanocrystalline soft magnetic alloy powder, a high-energy electric pulse technology is adopted, an amorphous alloy material is instantly and rapidly heated and exploded, the particle size of the powder is accurately regulated and controlled by accurately regulating and controlling an energy input parameter and a spacing parameter, and the high-sphericity soft magnetic powder with the median particle size being 0.5-5 microns is prepared; the uniformity and dispersity of the powder are remarkably improved, and the problem of low particle size control precision in the prior art is solved. The preparation method is simple in technological process and low in energy consumption, impurities and defects introduced in a traditional multi-step technology are avoided, and the purity and performance of the material are improved. The prepared amorphous nanocrystalline soft magnetic alloy powder has the characteristics of small particle size, high sphericity, high saturation magnetization, low coercive force and high yield, and is particularly suitable for the fields of high-frequency magnetic elements and precision electronic devices.

The application relates to a preparation method of a high-dielectric high-Curie-temperature garnet ferrite without rare earth, which comprises the following steps: pre-treating raw materials to make the raw materials with different particle sizes basically reach the same particle size state, and then obtaining mixed materials with uniform components through mechanical stirring and one-time granulation, so that ideal pre-sintering effect can be realized. Meanwhile, three kinds of second grinding materials with different pre-sintering temperatures and particle sizes are uniformly mixed to control the sintering activity of the powder, and the sintering process is matched, so that the microstructure of the sintered body can be finally improved, the porosity of the ferrite material is reduced, and the ferromagnetic resonance line width is reduced. Through the combined substitution of bismuth, zirconium and calcium elements and the adjustment of the preparation process, the particle size of the powder is adjusted, the sintering stage is controlled to the end of continuous grain growth, the microstructure of the garnet ferrite material is improved, and finally the ferrite material with high dielectric constant, high saturation magnetization, low ferromagnetic resonance line width and high Curie temperature is prepared.

The application belongs to the technical field of ferrite material preparation, and particularly provides a modified self-biased hexagonal gyromagnetic ferrite material and a preparation method thereof. The modified self-biased hexagonal gyromagnetic ferrite material comprises a main component and an additive. The main component comprises 74.5 mol% to 82.8 mol% of Fe2O3, 1.3 mol% to 6.1 mol% of Cr2O3, and the rest of BaCO3. Taking the weight of the main component after pre-sintering as a calculation basis, the additive comprises 0.5 wt% to 2.0 wt% of CaCO3, 0.5 wt% to 2.0 wt% of SiO2, and 0.1 wt% to 2.0 wt% of Bi2O3. The modified self-biased hexagonal gyromagnetic ferrite material (BaM) prepared through a sintering process optimization has the characteristics of high saturation magnetization (4πM s : 3.9~4.2kGs), high remanence ratio (M r / M s : 0.6~0.8), coercivity (H c : 450~550Oe), and low ferromagnetic resonance line width (ΔH: 230~280Oe), and meets the engineering requirements of microwave devices.

The present invention provides hexagonal ferrite magnetic powder which is extremely useful in achieving both an increase in recording density and an increase in SNR of a magnetic recording medium, is crystalline and has a high saturation magnetization. The hexagonal ferrite magnetic powder contains Bi in a range of a Bi / Fe molar ratio of 0.035 or less, has a saturation magnetization σs of 42.0 Am 2 / kg or more, and a Dx volume of 1800 nm 3 or less, based on a microcrystal diameter. The magnetic powder can be produced by a method for producing hexagonal ferrite magnetic powder, comprising a process of immersing hexagonal ferrite magnetic powder containing Bi in a solution in which a compound X that forms a complex with Bi is dissolved, thereby performing a treatment of dissolving a part of the Bi present in the hexagonal ferrite magnetic powder into the solution.

The application provides a magnetic tunnel junction device, comprising: a reference layer, a barrier layer, a free layer and a cap layer which are stacked, the reference layer has a fixed magnetization which is substantially perpendicular to the plane of the reference layer, the free layer has a magnetization which is substantially perpendicular to the plane of the free layer and can be switched between parallel or anti-parallel to the magnetization direction of the reference layer, the free layer comprises a first ferromagnetic layer and a second ferromagnetic layer which are stacked, the first ferromagnetic layer is arranged adjacent to the barrier layer and has a high saturation magnetization. The application can reduce the switching current of the magnetic tunnel junction device.

This invention discloses a method for preparing highly stable gyromagnetic ferrites, belonging to the field of magnetic material preparation technology. The method includes formulation preparation, multi-stage sand milling and granulation, molding and sintering, composite structure preparation, and precision machining steps. The formulation consists of VIII-series, IIIB-series, lanthanide-series, IVB-series, and VIIB-series metal oxides in a specific molar ratio, with rare earth nano-additives added to enhance lattice stability. Uniform slurry particle size is achieved through two-stage sand milling and spray granulation. A curved sintering process is used to control the temperature rise and oxygen content to obtain a high-density green body. A yttrium iron garnet or dysprosium iron garnet functional layer is formed on the surface of the green body by magnetron sputtering, constructing a multi-layer composite structure. Finally, a conductive modification layer is formed on the surface through integrated laser cutting and chemical mechanical polishing. The gyromagnetic ferrite material prepared by this method exhibits high saturation magnetization, low high-frequency loss, and excellent thermal stability, making it suitable for 5G communication, radar, and high-frequency microwave devices.

The application discloses a kind of dual-phase soft magnetic high-entropy alloy and preparation method thereof.The high-entropy alloy is composed of iron (Fe), cobalt (Co), chromium (Cr) and vanadium (V), with face-centered cubic (FCC) and body-centered cubic (BCC) dual-phase structure.The preparation method includes the following steps: design of dual-phase high-entropy alloy; preparation of alloy; homogenization treatment; controlled cold rolling; two-stage isothermal treatment.Based on the above process, the prepared high-entropy alloy has FCC and BCC dual-phase, FCC phase rich in Co, Cr and V, and BCC rich in Fe.Two-phase layered lamellar phase alternately forms pearlite-like structure.The dual-phase soft magnetic high-entropy alloy has high saturation magnetization (50-200 emu / g), low coercivity (50-100 Oe), high tensile yield strength (800-2000 MPa) and moderate plasticity (10-30%), and the mechanical and magnetic properties of the high-entropy alloy can be further adjusted by adjusting the heat treatment conditions.The method is simple and easy to operate, and can be widely applied to the preparation of various high-entropy alloys, with wide application prospect.

The invention relates to the technical field of amorphous alloy, in particular to a Fe-based amorphous alloy strip and a preparation method and application thereof, and the Fe-based amorphous alloy strip comprises the following elements of, by atomic percent, 75%-85% of Fe, 0.5%-4% of Si, 5%-12% of B, 0.1%-4% of P, 0.1%-4% of C, 0.5%-6% of Mo and 0.5%-5% of Ni. The sum of the atomic percentage contents of Fe, Si, B, P, C, Mo and Ni is 100%. According to the invention, the molybdenum element and the nickel element are introduced, so that the Fe-based amorphous alloy strip has high saturation magnetization, and meanwhile, the wear resistance and the toughness are remarkably improved.

This invention belongs to the field of metallic materials technology, and particularly relates to an Fe-Nb-B-Y amorphous alloy, its preparation method, and its applications. The alloy has the following atomic percentage expression: (Fe 85 B 14.7 Nb 0.3 ) 100‑x Y x Where 0.2≤x≤0.3. This Fe-Nb-B-Y amorphous alloy maintains high glass-forming ability while also possessing low coercivity and high saturation magnetization.

The invention discloses carbon-coated iron-cobalt nanoparticles with high saturation magnetization and low coercive force as well as a preparation method and application of the carbon-coated iron-cobalt nanoparticles. The preparation method comprises the following steps: mixing ferric nitrate and / or ferrous nitrate, cobalt salt, 2-methylimidazole and a solvent, stirring, and spin-drying to obtain an iron-cobalt bimetallic complex precursor; the molar ratio of ferric nitrate and / or ferrous nitrate to cobalt salt is (1-3): (1-2); the molar ratio of ferric nitrate and / or ferrous nitrate to 2-methylimidazole is 1: (1-25); and pyrolyzing the iron-cobalt bimetallic complex precursor in inert gas at 850-950 DEG C to obtain the carbon-coated iron-cobalt nanoparticles with high saturation magnetization and low coercive force. The method is mild in condition, simple in process and easy for large-scale production, and the graphitized carbon layer of the material can isolate oxygen and a corrosive medium and maintain high Ms of the iron-cobalt core; the electron coupling effect of the carbon shell and the iron-cobalt interface can reduce lattice distortion, inhibit magnetic domain wall pinning and reduce coercive force.

The invention discloses a metal-doped magnetic algae-based composite material as well as a preparation method and application thereof, and belongs to the technical field of composite material preparation. The preparation method comprises the following steps: crushing an algae biomass raw material to obtain pretreated algae slurry; the preparation method comprises the following steps: dissolving soluble trivalent ferric salt, soluble divalent ferrous salt and metal salt Mn < + > in water to prepare a mixed metal salt solution; adding the pretreated algae slurry into a mixed metal salt solution, under a stirring state, adjusting the pH value of a mixed system to be alkaline, carrying out a heating reaction, and after the reaction is finished, carrying out solid-liquid separation and washing to obtain a metal-doped magnetic algae-based precursor; and placing the metal-doped magnetic algae-based precursor in a high-temperature furnace under the protection of an inert atmosphere, carrying out heating treatment, and after pyrolysis is finished, cooling to room temperature to obtain the metal-doped magnetic algae-based composite material. The metal-doped magnetic algae-based composite material has high saturation magnetization, and can realize efficient adsorption of heavy metal ions and organic pollutants when being applied to wastewater treatment.

The present invention relates to a magnetic fish scale-based biochar and a preparation method thereof, as well as its application in degrading antibiotic wastewater. Cheap discarded fish scales are used as raw materials, which are modified by decalcification, crushing, and activation using an activator transition metal acetate. After freeze-drying, the pore structure is optimized by high-temperature pyrolysis to form a multi-activation site catalyst with surface-loaded bimetallic nanoparticles. The rapid electron transfer effect between carbon and transition metals is utilized to produce a large amount of active substances, thereby obtaining magnetic fish scale-based biochar with a high specific surface area and high saturation magnetization. The preparation method has simple and easy steps, low raw material cost, short production cycle, easy control of production process conditions, conventional equipment required, strong practicality and operability, and can be promoted and applied in large-scale industry. The application of the modified magnetic fish scale-based biochar in the treatment of antibiotic wastewater can effectively remove antibiotics in water and reduce the toxicity of wastewater.

The present invention relates to a magnetic TPE material and a preparation method thereof, belonging to the field of magnetic composite materials. The present invention discloses a magnetic TPE material and a preparation method thereof, wherein the weight components include 10-15 parts of hydrogenated styrene-butylene thermoplastic elastomer, 40-60 parts of active magnetic powder, 5-10 parts of polyolefin resin, 5-10 parts of polypropylene resin, 2-5 parts of compatibilizer, 10-25 parts of white oil, 0.1-0.5 parts of lubricant and 0.1-0.5 parts of antioxidant. The magnetic TPE material of the present invention adopts micro-nano lamination and low extrusion temperature preparation process. It can be used for injection molding or extrusion to make magnetic materials of different shapes, such as magnetic absorption nano data cables, charging cables, magnetic absorption panels, etc.; this product can obtain higher saturation magnetization while maintaining a good appearance, so that the product can maintain stable magnetic properties for a long time under different environments.

The invention discloses a high-entropy alloy modified fiber, a composite material and a preparation method thereof, and belongs to the technical field of protection. The high-entropy alloy modified fiber comprises carbon fiber and nano-particles which are physically pinned on the surface of the carbon fiber in a semi-embedded state; the nanoparticle comprises a metastable state high-entropy alloy core with high saturation magnetization, a dense dielectric oxide middle layer and a carbon shell. The ultra-fast Joule thermal shock technology is adopted to form a gradient sandwich core-shell structure of a metastable state alloy core, a compact oxide middle layer and a few-layer defect state carbon shell. The high-entropy alloy / fiber reinforced multifunctional composite material has a multi-stage interface structure, comprises a macroscopic fiber / matrix interface, a mesoscopic particle / fiber pinning interface and a microscopic particle internal core-shell interface, and is suitable for multifunctional integrated protection scenes such as electromagnetic stealth, severe environment corrosion resistance and impact and explosion resistance.

The application belongs to the field of soft magnetic high-entropy alloy material and magnetron sputtering technology, and particularly relates to a high-entropy alloy and nitride multilayer soft magnetic film for high frequency and a preparation method. The high-entropy alloy soft magnetic film layer comprises Zr and / or B, Fe, Co and Ni elements; the high-entropy alloy soft magnetic nitride film layer comprises Zr and / or B, Fe, Co, Ni and N elements, the N element is nitrogen gas with a certain partial pressure introduced in the magnetron sputtering process and nitrogen atoms are deposited into the high-entropy alloy soft magnetic nitride film layer, pure Ar and argon / nitrogen mixed gas are alternately used, the high-entropy alloy soft magnetic film layer and the high-entropy alloy soft magnetic nitride film layer are alternately sputtered on the surface of the substrate to obtain the multilayer soft magnetic film, the high-entropy alloy nitride soft magnetic film has high resistivity and low coercivity, the high-entropy alloy soft magnetic film has high saturation magnetization, the multilayer soft magnetic film has higher saturation magnetization and resistivity, and is suitable for high frequency application.

This invention discloses an iron-based amorphous nanocrystalline nanoparticle and its pressed magnetic core, preparation method, and application, belonging to the field of soft magnetic materials technology. The preparation method includes: target material preparation, using an induction melting furnace to prepare a master alloy ingot, and then machining it into the desired alloy target material using wire cutting; atomic fabrication of nanoparticles, using laser inert gas condensation technology to prepare iron-based amorphous nanocrystalline nanoparticle powder; and pressing molding, with a minimum molding pressure of less than 0.1 GPa. The iron-based amorphous nanocrystalline nanoparticle magnetic core of this invention has the following advantages: extremely low high-frequency loss, P cv (0.05 T, 100 kHz)=78‑94 mW / cm 3 , P cv (0.01 T, 1 MHz)=11‑53 mW / cm 3 It has a loss value far lower than that of traditional amorphous and nanocrystalline magnetic powder cores under the same conditions; and a high saturation magnetization intensity, which can reach 160-188 emu / g.

To achieve both a high saturation magnetization Ms and a low coercivity Hc in an iron-based amorphous alloy. An iron-based amorphous alloy is an iron-based amorphous alloy represented by a composition formula FeaSibBcPdCe, the composition ratio a satisfying 76.0≤a≤80.0, the composition ratio b satisfying 3.0≤b≤6.9, the composition ratio c satisfying 9.9≤c≤14.0, the composition ratio d satisfying 0.8≤d≤4.6, the composition ratio e satisfying 1.0≤e≤4.1.

The invention provides a hollow PtAgS nanocrystalline material as well as a preparation method and application thereof, and belongs to the technical field of synthesis of nano materials. A simple two-step hydrothermal method is adopted, firstly, a gel precursor is synthesized to serve as a self-sacrifice template, then a platinum source, a silver source, a sulfur source and the template are subjected to a hydrothermal reaction together, and the hollow PtAgS nanocrystal is obtained. According to the preparation method disclosed by the invention, platinum and silver atoms are induced to diffuse outwards from a sulfur-containing core by utilizing twin crystal defects formed in the initial stage of reaction, so that a hollow structure is formed; the process is simple and efficient, the product is pure, the structure is uniform and controllable, and the prepared hollow PtAgS nanocrystal is a ternary alloy nanocrystal with a uniform hollow structure, has twin crystal defects, shows excellent soft magnetic properties including high saturation magnetization and low coercive force, is particularly suitable for high-frequency and low-loss magnetic devices, and has wide application prospects. Such as miniaturized electronic components and magnetic sensors, and has a wide industrial application prospect.

The present application belongs to the field of electronic information functional materials and microelectronic devices, and relates to a microwave ferrite material, and particularly provides an LTCC high-curie-temperature NiZn ferrite substrate material and a preparation method thereof, to solve the defects of the existing low-temperature sintering NiCuZn ferrite substrate material, such as low curie temperature, high microwave magnetic loss and dielectric loss, low saturation magnetization and low dielectric constant; the present application uses Cu-doped high Ni / Zn ratio NiZn ferrite as a main material, and uses Bi2O3-CuO composite eutectic mixture as an auxiliary material, and the two are low-temperature co-fired to form a substrate material, which not only has a low sintering temperature (about 900 DEG C), but also has excellent microwave characteristics: high curie temperature (about 302 DEG C), low ferromagnetic resonance line width (about 100 Oe), low dielectric loss (loss tangent value about 8*10 ‑4 ) and high saturation magnetization (about 4959 Guass), which not only meets the requirements of the LTCC process, but also has excellent magnetic properties of the key substrate material required by the microwave ferrite device.

The invention provides a double-phase composite ferrite material as well as a preparation method and application thereof. The biphase composite ferrite material is prepared by compounding a SrBaM ferrite phase and a LiZn ferrite phase. The double-phase composite ferrite material is obtained by compounding the SrBaM ferrite phase and the LiZn ferrite phase, the SrBaM ferrite phase has the advantages of high saturation magnetization intensity, high residual magnetic induction intensity, high coercive force and the like, the LiZn ferrite phase has the advantages of high residual magnetism ratio, low line width, high Curie temperature and the like, and the SrBaM ferrite phase and the LiZn ferrite phase cooperate with each other, so that the composite material has the advantages of high saturation magnetization intensity, high residual magnetic induction intensity, high coercive force and the like. The structure and the electromagnetic property of the double-phase composite ferrite are improved, so that the double-phase composite ferrite has the advantages of low line width, low delta H, high remanence ratio, high Curie temperature and the like, and is suitable for a Ka-band self-biased circulator.

The invention relates to an iron-based amorphous alloy, a powder body thereof and a powder pressing material thereof. In the iron-based amorphous alloy, both high saturation magnetization Ms and low coercive force Hc are considered. The iron-based amorphous alloy is represented by the composition formula FeaSibBcPdCe, where the composition ratio a satisfies 76.0 < = a < = 80.0, the composition ratio b satisfies 3.0 < = b < = 6.9, the composition ratio c satisfies 9.9 < = c < = 14.0, the composition ratio d satisfies 0.8 < = d < = 4.6, and the composition ratio e satisfies 1.0 < = e < = 4.1.

The invention belongs to the field of electrochemical catalytic materials, and particularly relates to a method for preparing a ferromagnetic NiFeCo / CNFs alkaline OER catalyst based on Joule heat, which comprises the following steps: preparing a spinning solution, preparing CNFs precursor fibers by electrostatic spinning, and preparing the catalyst by Joule heat at different temperatures (600 / 800 / 1000 / 1200 / 1400 DEG C). Compared with other temperature samples, the NiFeCo / CNFs prepared by Joule heat at 1200 DEG C has the highest saturation magnetization intensity (13.7 emu / g) and the optimal alkaline OER performance, and the 30h stability retention rate exceeds 95%. The preparation method is simple and controllable, the material has high magnetism and high catalytic activity, a high-quality catalyst can be provided for the field of hydrogen production through water electrolysis, and the application prospect is good.

The present invention provides an undercooling solidification method for preparing an amorphous or nanocrystalline soft magnetic alloy with high Fe content and the applicable amorphous or nanocrystalline alloy composition. The undercooling solidification is realized by glass purification combined with cyclical superheating or electromagnetic levitation melting. An undercooling solidification alloy is prepared into amorphous strips or powders through rapid quenching or atomization of melt, and can be prepared into a nanocrystalline alloy through heat treatment. The chemical formula of the applicable amorphous or nanocrystalline alloy is FeSiBM, wherein M is one or more of P, C, Nb, Mo, Zr, Hf, Mo, Y, Cu and Co. The amorphous or nanocrystalline alloy prepared by undercooling non-equilibrium solidification has the characteristics of high amorphous forming ability, high saturation magnetization and low coercive force.

The application discloses a composite gyromagnetic ferrite substrate material for an LTCF phase shifter and belongs to the technical field of electronic ceramic materials. 4+ 3+ 3+ The main LiZn ferrite is selected from Ti 4+ , Mn 3+ , Bi 3+ ion substituted iron-deficient formula, which ensures low-temperature sintering and has high saturation magnetization and low ferromagnetic resonance line width; the auxiliary SrM ferrite is selected from micro-nano structure particles with high Curie temperature, the SrM ferrite with the structure has high sintering activity, and is beneficial to forming a multiple dense microstructure mainly with fine grains in the low-temperature sintering process, so that the material has high residual magnetism ratio and high saturation magnetization.

To provide a Co-free ferrite calcined body having a high saturation magnetization σs. [Solution] General formula showing the atomic ratio of metallic elements Ca, R, Fe, and Zn (where R is at least one rare earth element and must contain La): Ca 1-x R x Fe 2n-y Zn y A ferrite calcined body in which x, y, and n (where 2n is a molar ratio and is expressed as 2n = (Fe + Zn) / (Ca + R)) satisfy the following conditions: 0.35 ≤ x ≤ 0.7, 0 ≤ y < 0.5, and 4.5 ≤ n ≤ 6.0.

This invention relates to a low-loss microwave ferrite material for LTCF phase shifters and its preparation method, belonging to the field of electronic ceramic materials technology. The microwave ferrite material comprises a main material and auxiliary materials, with the auxiliary materials accounting for 0.01–2 wt.% of the main material. The main material consists of: Li₂CO₃ 11.65–12.33 mol%, ZnO 17.61–22.18 mol%, TiO₂ 8.22–13.31 mol.%, Mn₃O₄ 1.85–1.96 mol%, Fe₂O₃ 50.93–59.79 mol%, and Bi₂O₃ 0.08–0.09 mol%. The auxiliary material is rutile or anatase TiO₂ with a particle size of 5 nm–50 nm. The low-loss microwave ferrite material for LTCF phase shifters prepared by this invention, in addition to having a low sintering temperature (≤910℃), also has a narrow ferromagnetic resonance linewidth (≤90Oe) and low dielectric loss (<3×10⁻⁶). ‑4 It possesses high saturation magnetization (>3700 Gauss), high remanence ratio (>0.85), and high Curie temperature (>300℃). The fabricated microwave ferrite not only meets the requirements of LTCF process but also possesses excellent magnetic properties required for key substrate materials in microwave devices such as low-loss phase shifters.

This invention relates to the preparation of a nanocomposite permanent magnet material with high magnetic energy product and coercivity, comprising: preparation of solid epoxy resin, preparation of MnBi alloy ingot, and preparation of Mn... 55 Bi 45 Preparation of alloy hard magnetic phase bonded magnets, preparation of nanocrystalline Fe-Ni soft magnetic composite materials, and Mn 55 Bi 45 The preparation of Fe-Ni nanocomposite permanent magnet materials: This invention creatively combines methods such as arc melting, mechanical alloying, high-energy ball milling, and heat treatment. The resulting nanocomposite permanent magnet materials possess high magnetic energy product, excellent coercivity, high saturation magnetization, acid and alkali resistance, and high performance at low cost, making Mn... 55 Bi 45 / Fe-Ni nanocomposite permanent magnet materials have significant advantages in medical device applications within the big health industry.

The invention discloses a system, a process and a catalyst for driving rapid cold start of ammonia decomposition through magnetic induction heating, and belongs to the technical field of hydrogen energy preparation. The system comprises a gas path unit, a catalyst bed filled with a magnetic cobalt-based catalyst, a detection unit, a magnetic induction heating device and a hydrogen fuel cell integration unit. The catalyst takes Al2O3 as a carrier, metal cobalt nanoparticles are loaded, and the catalyst has high saturation magnetization. When the system works, the magnetic induction heating device generates an alternating magnetic field, so that the catalyst quickly generates heat, the ammonia decomposition reaction temperature can be reached within 10 seconds, and second-level cold start is realized. Meanwhile, the catalyst has high activity on ammonia decomposition, and the ammonia conversion rate is close to 100%. The problems that a traditional ammonia decomposition system is slow in starting and high in energy consumption are solved, and the system is particularly suitable for mobile scenes such as ammonia power vehicles and portable fuel cells needing rapid and instant hydrogen production.

This invention relates to the field of ferrite materials technology, and discloses a LiZnFe ferrite material with high saturation magnetization Ms and low ferromagnetic resonance linewidth. It utilizes a combination of main and auxiliary materials. The main materials are Li₂CO₃, Fe₂O₃, ZnO, MnCO₃, and TiO₂, with a molar ratio of 13-14:75-77:6-7.5:1.5-2.8:0.55-0.95. The auxiliary materials are CaCO₃ and Bi₂O₃, added at 0.5-2 wt% and 0.3-1.8 wt% of the total main materials, respectively. This invention solves the problems of insufficient magnetization Ms and low resonance linewidth in existing technologies by addressing both the formulation and preparation process, ensuring the material performance meets the requirements. The Ms can reach 5000 Gs, and the resonance linewidth can be within 200 Oe.