72 results about "Coercivity" patented technology

This application relates to the field of LNG cryogenic pressure vessel welding technology, specifically disclosing a multi-level collaborative control method for magnetic blow in 7Ni steel welding based on a quantified remanent magnetization threshold. Addressing the problems of severe magnetic blow and poor all-position welding stability caused by the high permeability, high coercivity, and difficulty in demagnetizing 7Ni steel, the method uses a remanent magnetization threshold of ≤50Gs to construct a collaborative control system encompassing pre-welding quantitative management, welding polarity and ground wire optimization, welding parameter and sequence constraints, real-time monitoring and automatic demagnetization closed-loop during welding, and post-weld quality verification. This application can effectively suppress all-position magnetic blow, avoiding defects such as arc deviation, incomplete penetration, slag inclusion, and porosity; achieving a first-pass yield of ≥97.5% for the main weld of the LNG storage tank, with a joint impact energy of ≥80J at -196℃ and a hardness of ≤300HV10, meeting cryogenic service specifications and applicable to the industrial welding production of large 7Ni steel LNG storage tanks.

The application relates to the technical field of magnetic materials, in particular to a preparation method of high-performance heavy-rare-earth-free neodymium iron boron magnets; the preparation method comprises the following steps: rapidly quenching a main phase alloy into a flake, obtaining coarse powder after hydrogen breaking; immersing the coarse powder in an ethanol mixed solution containing lanthanum nitrate and cerium nitrate, drying the pretreated coarse powder after ultrasonic-magnetic stirring cooperative treatment; adding an antioxidant and a lubricant into the pretreated coarse powder, preparing fine powder with an average particle size of 2-3.5 microns through airflow milling; performing magnetic field orientation compression molding on the fine powder under nitrogen protection, improving the density through cold isostatic pressing; finally, performing vacuum sintering and step-by-step tempering treatment to obtain the high-performance heavy-rare-earth-free neodymium iron boron magnets; wherein the main phase alloy is composed of the following components with mass percentage: 28-31wt.% Pr25Nd75, 0.88-1.2wt.% B, 0-0.1wt.% Al, 0.05-0.3wt.% Ti, 0.05-0.4wt.% Cu, 0.5-1.4wt.% Co, 0.1-0.4wt.% Ga, and the balance is Fe; the prepared neodymium iron boron magnet has the dual characteristics of high coercivity and high remanence, and effectively guarantees the performance and quality.

This invention relates to an Fe-Ni based alloy with enhanced soft magnetic properties utilizing a medium-range ordered structure and its preparation method. The chemical formula of the alloy is: Fe bal Ni a Cr y Si b B c M d Cu e X f Its microstructure is as follows: the alloy matrix is ​​mainly amorphous, with dispersed atomic-scale medium-range ordered (MRO) clusters comprising 15%–40% by volume. The size of these clusters is controlled between 1 nm and 5 nm, and no long-range crystalline phases larger than 10 nm are formed. By introducing Ni element to couple magnetic moments with Fe to reduce the saturation magnetostriction coefficient, and by using a low-temperature relaxation annealing process to control the pre-precipitation behavior of Cu element, a high-density MRO-reinforced framework is established in the amorphous matrix. This material possesses high saturation magnetic induction, low coercivity, and excellent high-frequency permeability, which can improve the problems of large magnetostriction coefficients and high high-frequency noise in existing high-Bs iron-based nanocrystalline alloys. It is particularly suitable for high-frequency high-power transformers and wireless charging magnetic shielding modules.

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.

A high-power, high-temperature-stability M-type strontium ferrite belongs to the field of ferrite material preparation technology. The ferrite comprises a main formulation of SrCO3, La2O3, CaCO3, MnO, SnO2, Fe2O3, and Co2O3, and additives composed of CaCO3, SiO2, H3BO3, and La2O3. This invention introduces Sn-Mn ions for co-substitution, thereby constructing a Sn... 4+ -Mn 2+ The charge balance mechanism effectively suppressed the Fe ionization induced by the introduction of high-valence ions. 3+ To Fe 2+ Price change behavior, effective compensation after replacement due to the introduction of non-magnetic Sn 4+ This results in a loss of lattice magnetic moment. Simultaneously, through a stepped pre-sintering and sintering process, a CoFe2O4 hard magnetic spinel phase is induced to precipitate in the M-type strontium ferrite main phase. The negative coercivity temperature coefficient of the CoFe2O4 phase complements the inherent positive temperature coefficient of the matrix.

The present application provides a magnetic layer having a coercive force Hc of 2.00 kOe or more and a residual magnetization Mrt per unit area of 2.00 memu / cm2 or more, which is achieved without using a non-magnetic underlayer for promoting in-plane orientation of the magnetic layer and without performing heat deposition 2 The above in-plane magnetization film, in-plane magnetization film multilayer structure, hard bias layer, magnetoresistance effect element, and sputtering target. The in-plane magnetization film has: a preliminary magnetic layer (12A) containing Co, Pt, and a non-magnetic grain boundary material and having a thickness of 1 to 32 nm; and a magnetic layer main portion (12B) formed on the preliminary magnetic layer (12A) and containing Co, Pt, and a non-magnetic oxide, the above non-magnetic grain boundary material of the preliminary magnetic layer (12A) containing at least one of a Zn oxide and a Ta oxide.

The application discloses a kind of saturation magnetic induction prediction of iron-based amorphous alloy, component design and super-high saturation magnetic induction iron-based amorphous / nanocrystalline alloy. Through machine learning model XGBoost combined with SHAP analysis reveals the core role of ferromagnetic element content, alloy mixing enthalpy and electronegativity difference, while maintaining high ferromagnetic element content, without deteriorating amorphous forming ability, after annealing can obtain very low coercivity, realize high saturation magnetic induction and amorphous forming ability, the synergistic optimization of coercivity. The parameters used in the composition design criteria proposed by the application do not require experimental data and can be calculated directly from the alloy composition. Combined with machine learning model, high-performance components can be quickly screened, significantly reducing the development cycle and cost of traditional trial-and-error method, providing systematic theoretical guidance for the development of high-performance soft magnetic materials and improving industrial feasibility.

This invention discloses a method for improving SmFe 12 A method for determining the magnetic properties of sintered permanent magnet materials. The method includes: using a low-melting-point rare-earth-rich alloy sheet as a diffusion source to conduct magnetic analysis on SmFe2... 12 The sintered permanent magnet material is sandwiched and heat-treated to achieve SmFe 12 The magnetic properties of sintered permanent magnet materials are improved; wherein the low-melting-point rare-earth-rich metal sheet includes Sm sheet and / or Sm alloy sheet. The modified SmFe prepared by this invention... 12 Sintered permanent magnet materials exhibit continuous grain boundary phases, high coercivity, and high energy product. Room temperature coercivity can be increased by 2000–8000 Oe. This method is simple and effective, and is applicable to SmFe... 12 This provides a new approach to improving the overall magnetic properties of sintered permanent magnet materials.

The application relates to the technical field of amorphous soft magnetic material preparation, and discloses a cobalt-based amorphous soft magnetic alloy material, a preparation method thereof and application. a Fe b Mo c Si d B e C f M g In the formula, a, b, c, d, e, f and g respectively represent the atomic percentage content of corresponding components; wherein 50<=a<=70, 2<=b<=8, 0.5<=c<=5, 10<=d<=20, 10<=e<=20, 0.01<=f<=0.5, 0.1<=g<=5, and a+b+c+d+e+f+g=100; and M represents at least one of elements V, Cr, Mn and Nb. The cobalt-based amorphous soft magnetic alloy material provided by the application has low saturation magnetic induction intensity, low coercive force, high rectangular ratio and other superior soft magnetic properties, is good in corrosion resistance and easy to prepare; and a magnetic probe prepared from the alloy material has high precision in sensor testing, and has important significance for promoting the development of small high-precision magnetic flux gate current sensors.

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 application relates to a low-cost high-saturation-flux-density iron-based amorphous nanocrystalline soft magnetic alloy and preparation and application thereof, and aims to solve the technical problems of high cost, difficult consideration of high saturation magnetic induction and low coercivity, and narrow heat treatment process window of existing iron-based nanocrystalline soft magnetic alloys. 82 Si a B b P c Mo 0.5 Cu x , wherein 2.79<=a<=2.87, 12.07<=b<=12.44, 1.39<=c<=1.44, 0.75<=x<=1.25, and a+b+c=17.5-x. The alloy can optimize the soft magnetic performance by adjusting the Cu content and the annealing process. Under the optimal test condition, the saturation magnetic flux density of the typical component alloy can reach 1.82 T, and the coercivity is as low as 1.4 A / m, thereby forming an excellent combination of high magnetic energy storage and low magnetic hysteresis loss, and being suitable for the scene of high magnetic flux and low loss of a soft magnetic device.

This invention discloses a method for preparing permanent magnets by low-temperature orientation molding and hot-pressing densification of omnidirectional NdFeB magnetic powder, relating to the field of permanent magnet materials technology. The invention includes the following steps: Fe, B-Fe alloy, and Co are melted, and Nd, Ga, Al, and Cu are added and melted. After casting, the mixture is vacuum annealed, crushed, and treated in a hydrogen atmosphere at 300-350℃, followed by vacuum treatment at 350℃, then treatment in a hydrogen atmosphere at 800-820℃ and 80kPa, and then vacuum treatment in a constant axial static magnetic field at 800℃, 0.08-0.1Pa, and 2.2-2.5T. After discharge, the material is pretreated with a dilute nitric acid aqueous solution, then modified with a modified suspension and modified nanosheet dispersion, and finally subjected to warm pressing, vacuum degreasing, and hot pressing to obtain an omnidirectional NdFeB permanent magnet with excellent remanence, intrinsic coercivity, maximum energy product, and squareness.

The present invention belongs to the technical field of rare earth permanent magnet materials, and specifically relates to a high-abundance rare earth rapid quenching alloy and a preparation method thereof. In order to synergistically improve the solubility of La, the Ce 3+ proportion and magnetic properties in the high-abundance rare earth rapid quenching alloy, the high-abundance rare earth rapid quenching alloy of the present invention is expressed in atomic percentage as (La 1.53 Ce 3.57 RE 11.9 )-M x Fe 78‑x -B6, where 0 < x < 1; RE is an optionally added rare earth element selected from one or more of Nd, Pr, Dy, and Tb; M is a doping element selected from at least one of Ag, Sn, Au, and Cu, and the mixing formation enthalpy of the binary system formed by M and Fe is greater than the mixing formation enthalpy of the binary system formed by La and Fe, and it is prepared by a two-step method of vacuum induction melting and melt rapid quenching. The present invention can significantly improve the solubility of La in the matrix phase, and while maintaining a high proportion of Ce 3+ , it greatly optimizes the coercivity and the maximum magnetic energy product.

This invention relates to a rare-earth permanent magnet material Sm2(Co,Fe,Cu,Zr). 17 The method for preparing the permanent magnet material, wherein the chemical formula of the permanent magnet material is Sm2Co. 17‑a‑b‑c Fe a Cu b Zr c Where 0.15≤a≤0.35, 0.05≤b≤0.15, 0.02≤c≤0.05, and a+b+c≤0.50; the permanent magnet material has a 2:17 rhombohedral crystal structure with space group R-3m and an average grain size of 3-8μm; the preparation method includes vacuum melting, homogenization treatment, powder preparation, magnetic field orientation forming, cold isostatic pressing, sintering, and graded aging treatment steps. This invention improves the coercivity and maximum energy product of the permanent magnet material and enhances its temperature stability by optimizing the Fe, Cu, and Zr element ratio and introducing a multi-stage heat treatment process.

This invention relates to the field of neodymium iron boron (NdFeB) magnet technology, specifically to a NdFeB magnet and its preparation method, comprising the following preparation steps: S1. Melting the alloy matrix and modified auxiliary alloy separately in a vacuum induction melting furnace, casting them into thin sheets to obtain a main phase alloy casting and a modified auxiliary phase alloy casting; S2. Mixing the main phase alloy casting and the modified auxiliary phase alloy casting, crushing them into coarse powder, and then pulverizing them into fine powder in an air jet mill; S3. Uniformly spraying the powder modifier onto the flowing magnetic powder through an atomizing nozzle at the discharge port, mixing them, magnetizing and oriented them in a directional magnetic field, pressing them, and then cold isostatically pressing them to obtain a green blank; S4. Sintering the green blank, holding it at a temperature, and then performing a two-stage tempering treatment to finally obtain the NdFeB magnet. This invention achieves a simultaneous increase in remanence, coercivity, and magnetic energy product through the synergistic effect of the modified auxiliary alloy and the powder modifier, breaking the trade-off between coercivity and remanence in traditional technologies.

The present disclosure relates to a sintered neodymium-iron-boron magnet and a method for preparing the same, the magnet comprising a main phase and a grain boundary phase, a ratio of an average grain size of a surface layer of the magnet to an average grain size of a central region of the magnet being 1.05-1.35; wherein the surface layer of the magnet refers to a region at a distance of 35 μm or less from a surface of the magnet; and the central region of the magnet refers to a region at a distance of 500 μm or more from the surface of the magnet. The sintered neodymium-iron-boron magnet has a sum of a maximum magnetic energy product (BH)max and an intrinsic coercivity HcJ of greater than 80; and a remanence Br of greater than 13 KGs; the maximum magnetic energy product (BH)max has a unit of MGOe, and the intrinsic coercivity HcJ has a unit of KOe.

The application discloses a permanent magnet ferrite and a preparation method thereof, and belongs to the field of permanent magnet materials. The permanent magnet ferrite comprises single-domain main phase crystal grains and a calcium-rich grain boundary phase coated outside the single-domain main phase crystal grains, and the chemical formula of the single-domain main phase crystal grains is: SrFe 12‑y‑z‑m‑n Al y Cr z Mn m Ti n O 19 wherein 0.05<=y<=1.0, 0.05<=z<=0.6, 0.10<=y+z<=1.5, 0.005<=m<=0.10, 0.005<=n<=0.10, and 0.8<=m / n<=1.2; Mn and Ti elements are enriched on the outer edge of the single-domain main phase crystal grains and form a double-layer pinning structure with the calcium-rich grain boundary phase. In the preparation process, a segmented magnetic field assisted sintering is used to control the grain orientation. Through the synergistic effect of the grain boundary pinning mechanism and the magnetic field orientation control, the grain size is controlled within the single-domain range, the grain interior does not have obvious multi-domain structure, the orientation consistency and the magnetic performance of the material are improved, and the permanent magnet ferrite has high coercivity and high remanence performance.

This invention discloses an iron-cobalt-based nanocrystalline alloy material and its preparation method, relating to the technical field of soft magnetic alloy materials. The material composition is: (Fe... a Co b ) 73.5‑x Cu c Nb d Si e B f Y x The specific contents of a, b, c, d, e, f, and x are as follows: 0 ≤ x ≤ 5, 0.7 ≤ a ≤ 0.9, 0.1 ≤ b ≤ 0.3, a + b = 1, 0.9 ≤ c ≤ 1.1, 2.8 ≤ d ≤ 3.2, 12.0 ≤ e ≤ 16.0, 8 ≤ f ≤ 10, c + d + e + f = 26.5. This invention provides an iron-cobalt-based nanocrystalline alloy material with higher permeability, higher saturation magnetic induction, and lower coercivity. Furthermore, this material exhibits a higher specific magnetic susceptibility, meeting the requirements of high-power-density devices for material miniaturization and lightweighting.

The application discloses a neodymium-iron-boron magnet material and a preparation method, application and motor thereof. The neodymium-iron-boron magnet material comprises an amorphous RE-rich phase in a grain boundary phase, the element composition and atomic ratio of the amorphous RE-rich phase are TM:RE:Cu:Ga=(15-30):(40-60):(10-25):(10-30), and the volume ratio of the amorphous RE-rich phase in the grain boundary phase is 3-8%. TM is Fe and Co, and RE is a rare earth element. The neodymium-iron-boron magnet material can improve coercivity without using or using heavy rare earth elements, while maintaining high remanence and magnetic energy product.

The application relates to the technical field of soft magnetic alloy, in particular to a soft magnetic alloy and a preparation method thereof. The preparation method comprises the following steps: providing a soft magnetic alloy blank; performing plastic deformation treatment on the soft magnetic alloy blank to obtain a plastic deformation piece; and performing post-treatment on the plastic deformation piece, wherein the post-treatment comprises at least one electric pulse treatment and at least one annealing heat treatment, so as to obtain the soft magnetic alloy. According to the method, plastic deformation is performed on the soft magnetic alloy blank, electric pulse treatment and annealing heat treatment are performed on the plastic deformation piece, and the synergy of the two energy fields can significantly improve the yield strength and elongation of the obtained soft magnetic alloy, effectively reduce the coercive force of the soft magnetic alloy, and make the soft magnetic alloy have excellent strength, excellent toughness and excellent magnetism.

This invention relates to the field of soft magnetic materials technology, and in particular to a Fe-Co-Al soft magnetic material, its preparation method, and its applications. The material is prepared from Fe, Co, and Al as raw materials, weighed according to an atomic ratio of Fe:Co:Al = 3:1:1, and then processed through melting, rapid cooling, and heat treatment to obtain a soft magnetic material with the chemical formula Fe₃CoAl. The resulting material has a fully ordered cubic crystal structure of type DO₃. At room temperature, it exhibits a saturation magnetization of 162 emu / g, a coercivity of approximately 28.5 Oe, and a steep initial magnetization curve, demonstrating excellent magnetization sensitivity and rapid response even under weak magnetic fields. The Fe₃CoAl soft magnetic material of this invention significantly improves permeability and reduces coercivity through the introduction of Co, and its preparation process is simple, has a short cycle time, and is suitable for industrial production.

The application discloses a method for regulating energy state of amorphous alloy to improve soft magnetic performance. The method adopts a base bearing type hot pressing process, lays an iron-based, cobalt-based or nickel-based soft magnetic amorphous strip on the surface of a porous base, carries out hot pressing treatment under the synchronous action of heating and pressing, and cools under the pressure maintaining condition, so that the energy state of the soft magnetic amorphous alloy is effectively regulated. The obtained soft magnetic amorphous alloy maintains a complete amorphous structure, the energy state is obviously optimized relative to the original strip, the saturation magnetic induction intensity is improved, and the coercive force is reduced. The application has the advantages of mild process, conventional equipment and easy large-scale production, and has important significance for performance regulation and engineering application of amorphous soft magnetic materials.

This invention discloses a dual-phase cerium-rich NdFeB magnet and its preparation method, comprising 29%~33% Re, 0.1%~2% M, 0.9%~1% B, and the balance Fe by mass percentage. This application also provides a method for preparing the magnet, which employs a dual-phase alloy composition design. By adding a high-praseodymium-neodymium main phase alloy II, grain boundaries are improved, coercivity is enhanced, and the squareness of the magnet is ensured. Simultaneously, Al is introduced to ensure uniform distribution within the NdFeB main phase grains and grain boundary regions, thereby improving the magnetic properties of the magnet while significantly enhancing its mechanical properties and structural stability.

System 12 comprises a permanent magnet 14, a switchable magnet system 16 and optionally a magnetic field conduit 18 (e.g. comprising steel or soft ferromagnetic material with coercivity of <1 kA / m) ar

This invention provides a soft magnetic powder that combines low coercivity and high saturation magnetic flux density, a pressed magnetic core containing the magnetic powder, magnetic components, and an electronic device capable of miniaturization and high output. The soft magnetic powder is characterized by comprising particles having Fe... x Cu a Nb b (Si 1‑ y B y ) 100‑x‑a‑b [Where, a, b, and x are numbers in atomic percentage, satisfying 0.3 ≤ a ≤ 2.0, 2.0 ≤ b ≤ 4.0, and 73.0 ≤ x ≤ 79.5; furthermore, y is a number satisfying f(x) ≤ y ≤ 0.99, and f(x) = (4 × 10⁻⁶) / ( ... ‑34 )x 17.56 The composition is represented by ], wherein the particles contain crystalline grains with a diameter of 1.0 nm or more and 30.0 nm or less, and include a Cu segregation portion, wherein the Cu segregation portion exists at a depth of more than 30 nm from the surface of the particles, and the maximum Cu concentration of the Cu segregation portion is greater than 6.0 atomic percentage.

This invention belongs to the field of rare earth permanent magnet materials technology, specifically relating to a neodymium iron boron magnet material and its preparation method. The magnet material is composed of PrNd 26.0~30.0%, B 0.88~0.98%, Co 0.25~0.45%, Zr 0.15~0.30%, Ga 0.15~0.30%, Al 0.05~0.15%, Cu 0.15~0.30%, Ca 0.05~0.25%, Sr 0.03~0.15%, Ba 0.02~0.10%, and the balance Fe. The preparation process involves first smelting the main alloy in small quantities and then powdering it. The remaining components are then vapor-deposited with alkaline earth metals onto the surface of the powder. The resulting material is then formed, sintered, and tempered to obtain the magnet. This invention achieves high remanence, high coercivity, high squareness, and excellent batch consistency without using heavy rare earth elements.