1960results about How to "Improve magnetism" patented technology

The invention discloses a method for preparing sintered NdFeB with low dysprosium (Dy) content and high performance; the method comprises the following steps of: sputtering and plating the Dy element on the surface of jet mill powder by using the powder plate technology based on magnetron sputtering on the basis of preparing NdFeB powder, and then sufficiently dispersing the Dy element to micron-sized NdFeB crystal particles by dispersing the Dy element at high temperature in the sintering and tempering process, thereby achieving the effect of improving magnetic performance of the sintered NdFeB. Compared with the introduction of the Dy element in the proportioning process of the prior art, the method disclosed by the invention has the advantages: the low dysprosium content and high performance is limited in the nano-size by adopting the physical gas-phase deposition, the consumption quantity of the Dy element during the production process is controlled effectively and the preparationof sintered NdFeB with low dysprosium content and high performance is realized. Compared with the sintered NdFeB of the same components prepared by the traditional casting and powder metallurgy process, both the intrinsic coercivity and the maximum magnetic energy product of the sintered NdFeB rare-earth permanent magnetic material obtained according to the invention are improved obviously; compared with the sintered NdFeB with the same performance prepared by the traditional casting and powder metallurgy process, the dosage of the dysprosium element is reduced remarkably. The method can be widely applicable to producing and manufacturing sintered NdFeB with high performance.

A motor including an outside rotor having a rotor disc with plural magnets alternating polarities flush mounted in the disc, an inside stator assembly with a ring of pole pieces forming a channel to house a transversely wound stator windings, and a controller coupled with feedback electronics for monitoring a timing, speed and direction and coupling a signal to a processing unit for adjusting the drive electronics driving the phase windings. A u-shaped gap above the channel to receive the rotor disc and focus the captured magnetic flux in the pole pieces toward the magnets. In an embodiment the molded magnetic flux channel pole pieces of the inside stator are sets of molded magnetic flux channel pole pieces, each set forming a channel and corresponding to one phase of the motor; and a section of each one of the transverse windings passing through one channel, the remaining section folding back outside the set in close proximity to the outer base of the set of molded magnetic flux channel pole pieces.

A magnetoresistive element includes a magnetoresistive film including a magnetization pinned layer, a magnetization free layer, an intermediate layer arranged between the magnetization pinned layer and the magnetization free layer, a cap layer arranged on the magnetization pinned layer or on the magnetization free layer, and a functional layer formed of an oxygen- or nitrogen-containing material and arranged in the magnetization pinned layer, or in the magnetization free layer, and a pair of electrodes which pass a current perpendicularly to a plane of the magnetoresistive film, in which a crystalline orientation plane of the functional layer is different from a crystalline orientation plane of its upper or lower adjacent layer.

A cold rolling method for preparing high-Si steel sheet containing Fe (85-96 Wt%) and Si (4-15) includes such steps as providing raw material containing Si, B and Fe, smelting, casting, forging, hot rolling, warm rolling, heat treating and cold rolling.

The invention discloses a method for preparing a heavy rare earth hydride nano-particle doped sintered NdFeB permanent magnet, which belongs to the technical field of magnetic materials. The prior preparation method improves the coercive force and the temperature stability of magnets by adding heavy rare earth elements, namely terbium or dysprosium into master alloy, but the method can cause the residual magnetism of the magnets, the reduction of magnetic energy product and the increase of manufacturing cost. The method adopts heavy rare earth terbium hydride and dysprosium hydride nano-powder doping technology to prepare the sintered NdFeB permanent magnet with high coercive force and excellent magnetic property. The method comprises the following steps: preparing NdFeB powder by a rapidly solidified flake process and a hydrogen decrepitation process; preparing the terbium hydride or the dysprosium hydride nano-powder by physical vapor deposition technology; mixing the two powders, and performing magnetic field orientation and press forming; and performing dehydrogenation treatment, sintering and heat treatment on a green compact at different temperatures, and obtaining the sintered magnet. The coercive force of the magnet prepared by the method is higher than that of the prior sintered magnet with the same ingredients; and compared with the sintered magnet with the equivalent coercive force, the proportion of the terbium and dysprosium needed by the magnet prepared by the method is remarkably reduced.

A method and apparatus for reconfiguring a file or logical volume stored on a magnetic disk storage system for optimal performance. The magnetic disk storage system contains a cache volume constituted as free storage. When appropriate, a file can be copied from its normal storage location to the cache volume with a different format to optimize the file for subsequent operations. After such operations are complete, the file can be transferred from the cache volume back to the normal storage location in the original format.

The invention discloses a preparation method of carbon-coated metallic nano-particles, which comprises the steps that: NaCl serves as dispersant and a carrier, and is fully mixed with a metal source and a solid carbon source; the mixed solution is dried under a vacuum condition, and mixture is obtained; the mixture is put into a tubular furnace and calcinated in the inertial/reduction atmosphere, and a calcinated product is obtained; and the calcinated product is washed and ground, and the carbon-coated metallic nano-particles are obtained. The method is safe, non-toxic, environmental-friendly and simple to operate, so that the grain sizes of the prepared carbon-coated nano-particles are controlled to be 0nm to 100nm, the graphitization degree of a carbon layer is high, the dispersion of the particles is good, and the yield is high. The carbon-coated metallic nano-particles which are prepared through the preparation method have better magnetism and larger specific surface areas, can be used for electronic and magnetic materials, and can be used for magnetic resonance imaging, targeted drug transportation and other fields through functionalization treatment and other steps.

A magnetic recording medium is provided with an orientation control layer and an underlayer disposed above the substrate, an underlayer disposed above the orientation control layer, and a recording layer having an hcp crystal structure and disposed on a surface of the underlayer. A part of the recording layer is epitaxially grown on the surface of the underlayer and has c-axes that are inclined with respect to a surface of the substrate.

The invention discloses a magnet and a manufacturing method thereof, more particularly a sintering magnet with outstanding corrosion resistance and high performance R-(Fe, TM)-Cu-B-X system and a manufacturing method thereof; condition of the magnet is HAST experiment of 130 DEG C, 95% rRH, 2,7bar air pressure, magnet weightlessness in 20 days is less than 2mg/cm<2>, sum of [(BH)max]+[jHc] reaches 64-75, density of the magnet reaches 7.56-7.8g/cm<2>; in the process of manufacturing, an oxygen-free procedure technology using inertia gases or N<2> gas for protection controls contents of oxygen, carbon, nitrogen and hydrogen in the magnet, adjusts cooling speed of a continuous casting furnace with blanks, and controls thickness of an alloy sheet, granularity of powders and pressed compact density within a special range in order to obtain the sintering magnet with outstanding corrosion resistance and high performance R-Fe-B system, greatly saving the strategic metal Co and reducing the cost.

A perpendicular magnetic write head having a conformal wrap around trailing shield. The write head includes a write pole that can be configured with a trapezoidal shape as viewed from the Air Bearing Surface (ABS) and which includes a wrap around trailing magnetic shield. The magnetic shield has a trailing portion that is separated from the leading edge of the writ pole by a non-magnetic trailing gap, and has side shield portions that are separated from first and second side portions of the write pole by first and second non-magnetic side gaps. The magnetic shield can be configured with notches at either side of the trailing portion of magnetic shield. These notches can extend in the trailing direction by a distance that is preferably ¼ to 1 times the trailing gap thickness. The width of the straight, trailing portion of the shield is preferable ½ to 1 times of the main pole width.

The invention discloses a preparing method of a metal magnetic powder core. The preparing method includes the following steps that (1) master alloy is melt through a vacuum induction furnace, and an alloy thin belt is obtained through a quick quenching device; (2) ball milling is conducted on the thin belt; (3) annealing is conducted on powder; (4) particle size distribution is conducted on the annealed powder; (5) passivant is added into the distributed powder to conduct passivating on the powder, and then a binding agent and an insulating agent are added into the powder to conduct insulating bonding and wrapping on the powder; (6) a lubricating release agent is then added, the mixture is mixed, and compression moulding is conducted; (7) annealing is conducted on a sample obtained through compression moulding, and the sample is cooled along with the furnace, and spraying and coating are conducted to obtain the target product. According to the preparing method, the master alloy contains an appropriate number of alloy elements, so that the alloy processing performance is improved; the alloy powder and an insulating medium are mixed and pressed to be the magnetic powder core, so that eddy-current loss under a high frequency can be greatly reduced; meanwhile, the problem that alloy materials are limited in use due to single shapes is solved through shape diversity of the magnetic powder core.

The embodiment of the invention discloses a preparation method of nano-silver dispersion liquid. The preparation method comprises the following steps that thickening agents and dispersing agents are added into pure water or deionized water, then, soluble silver salt is dissolved in solution, and the silver salt solution is obtained; and under the stirring effect, silver complexing agents are firstly added into the silver salt solution, then, reducing agents are added, or silver complexing reduction agents are directly added, the reaction is carried out for at least 12 hours under the condition of room temperature to 90 DEG C, silver ions in the silver salt solution are reduced into metal silver, the nano-silver dispersion liquid is obtained, the silver complexing agents and the silver complexing reduction agents can form the chemical bonding with the nano-silver particle surface, and in addition, functional groups with the cross linking effect are reserved. The invention correspondingly provides the nano-silver dispersion liquid prepared by the method. The process of the preparation method is simple, the stability of the prepared nano-silver dispersion liquid is good, nano-silver particles are uniform, the application is convenient, and the bonding force of the nano-silver and substrates is high. In addition, the invention also provides a preparation method of a nano-silver antibacterial coating.

The invention discloses a preenrichment-three segment suspension roasting-magnetic separation treatment method of complex refractory iron ores, and belongs to the technical field of mineral processing. The method comprises the following steps: 1, levigating the complex refractory iron ores, carrying out weak magnetic separation, and carrying out strong magnetic separation on mine tailings; 2, putting concentrate obtained after strong magnetic separation in a suspension roasting furnace, and heating to 450-800DEG C in a suspension state in order to carry out pre-oxidation roasting; 3, introducing nitrogen to displace air, and introducing a reducing gas to carry out reduction in a suspension loose state; 4, introducing air when the temperature decreases to 250-400DEG C in order to oxidize, taking out the obtained material when the temperature decreases to below 100DEG C, and carrying out ore milling; and 5, carrying out third segment magnetic separation, and mixing concentrate obtained after three segment magnetic separation with concrete obtained after the weak magnetic separation to obtain finial concentrate. The method has the advantages of simple process, improvement of the recovery rate of the complex refractory iron ores, strong adaptability, safe and reliable process, uniform and stable product quality, energy saving and consumption reduction.

The invention discloses a flexible rare earth bonded magnet with roll anisotropy and a manufacturing method thereof. The magnet comprises the following components in part by mass: 94 to 97 parts of anisotropic rare earth composite permanent magnet powder, 2.8 to 5.5 parts of binder and 0.2 to 0.5 part of processing aid, wherein the anisotropic rare earth composite permanent magnet powder comprises anisotropic ferrite permanent magnet powder, anisotropic samarium-iron-nitrogen permanent magnet powder, anisotropic neodymium-iron-nitrogen permanent magnet powder and neodymium-iron-boron permanent magnet powder with roll anisotropy. The anisotropic rare earth composite permanent magnet powder is subjected to surface treatment by using a surface treatment agent. A permanent magnet product with the thickness of 0.35 to 8mm and the maximum width of 1,000mm can be manufactured by processing the components by a calendering method; the disadvantages of various conventional permanent magnet materials are overcome; and a magnetic material which has a thin wall, large length-diameter ratio, high flexibility and higher magnetic performance can be manufactured under the condition that an oriented magnetic field is not required to be applied.

The invention discloses a method and a device for preparing a high-silicon silicon steel thin strip under a magnetic field through a powder diffusion method. According to the method, holes are formed in a low-silicon steel strip to be machined, then surface reinforcing treatment is carried out on the low-silicon steel strip to be machined, the holes are filled with an iron-silicon alloy powder and rolling forming is carried out on the powder, and then heat treatment is carried out on the powder in a magnetic field environment to obtain the high-silicon silicon steel thin strip with certain orientation, a silicon content of 6.5wt%Si and excellent magnetic performance. According to the method and the device, long-size and continuous operation can be realized; and moreover, a near-net-shape thin strip can be prepared, and therefore, a preparation cost can be remarkably lowered.

The invention relates to a double-hard magnetic main phase mixed rare-earth permanent magnet and a preparation method thereof. The permanent magnet comprises double hard magnetic main phases and a rear-earth-rich phase, wherein the double hard magnetic main phases are MM<2>Fe<14>B and (PrNd)<2>Fe<14>B respectively; the permanent magnet is prepared from the following chemical component in percentage by mass: [MM<x1>(PrNd)<1-x1>]<x>Fe<100-x-y-z>B<y>TM<z>; x is smaller than or equal to 31 and greater than or equal to 27; x1 is smaller than or equal to 1 and greater than or equal to 0; y is smaller than or equal to 1 and greater than or equal to 0.9; z is smaller than or equal to 1.5 and greater than 0; TM is a composition of more of the elements Al, Cu, Co, Nb, Ga, Tb and Zr; and MM is a mixed rare-earth alloy which is directly separated from raw ore and contains La, Ce, Pr and Nd. The anisotropic sintered mixed rare-earth permanent magnet with high cost performance within a range of 10-48MGOe can be prepared by adjusting the content of PrNd. A basic rare-earth raw material used by the permanent magnet is cheap mixed rare earth, so that a separation and purification technology for the rare earth can be reduced, efficient utilization of lanthanum-cerium rare earth is achieved and the double-hard magnetic main phase mixed rare-earth permanent magnet meets the requirements of low carbon economy on green production technology innovation of a rare-earth permanent magnet product.

The invention discloses a nano toughening NdFeB magnetic material and a preparation method of the nano toughening NdFeB magnetic material. The main mechanism is that a nano composite crystal boundary phase is formed on an NdFeB main phase crystal boundary, an H-grade rare earth permanent magnetic material with high coercive force M is prepared without doping any heavy rare earth, and then, a SH-grade rare earth permanent magnetic material is prepared by adding a little heavy rare earth. The nano material is prepared by a plasma arc method, has a grain size of 5-80nm and mainly contains metallic elements, such as Al, Cu, Cr, Co, Fe, Zn and the like, and all kinds of rare earth elements. A NdFeB main phase having a rare earth content of Pr-Nd is prepared by a SC-HD process; after smelting and hydrogen breaking, the product grain size is milled to be about 3.5 microns by an air-current mill, and in the argon protection atmosphere, a nano additive is added in a manner of jetting composite, so the nano additive is uniformly attached to the NdFeB main phase. In the sintering process, the nano powder and the main phase form the crystal boundary, the coercive force of NdFeB is greatly increased, and since the product has uniform crystal components, the machining property is also elevated well, the NdFeB magnetic material can be applied to the wider field. At the same time, the technical process is simple, low-cost and suitable for the batch production.

The invention relates to a non-oriented high-silicon electrical steel ribbon and its making method, and belongs to the fields of the metallurgical technology and the material science. The chemical components of the ribbon comprise 4.5-7.0wt% of Si, 2.0-5.0wt% of Cr, 0.06-1.0wt% of Al, 0.3-0.8wt% of Mn, 0.005wt% or less of N, 0.004wt% or less of S, 0.02wt% or less of P, 0.003wt% or less of O, 0.005wt% or less of C, and the balance Fe, and the thickness of the ribbon is 0.35-0.5mm. The making method comprises the following steps: smelting non-oriented high-silicon steel in a vacuum smelting furnace; carrying out double-roller ribbon roll-casting at a casting temperature of 1420-1460DEG C to the ribbon thickness of 1.0-1.5mm; carrying out hot rolling of the ribbon at 800-1100DEG C to the hot rolled ribbon thickness of 0.8-1.0mm; pickling, and preheating the ribbon, and carrying out warm rolling at 400-700DEG C; and annealing. The addition of the Cr element in the high-silicon electrical steel ribbon obviously improves the processing performance of the high-silicon steel ribbon, the iron loss value is same to the iron losses of present high-silicon steel products, and the magnetic induction intensity is above 0.03T higher than that of the present products. The making method has the advantages of simple technology, low energy consumption, high yield, and excellent product magnetic property.

The invention belongs to the field of magnetic material and specifically relates to a ferrite injection molding granule, which contains the following constituents in percentage by weight: 85-92% of ferrite magnetic powder, 0.3-0.5% of coupling agent, 7-14% of bonder and 0.1-0.5% of lubricant, wherein the bonder is mixture of PPS (polyphenylene sulfite) and PA (polyamide). The invention also provides a preparation method of the ferrite injection molding granule, which comprises a step of modifying magnetic powder surface, a step of mixing glue with magnetic powder, a step of lubricating and a step of mixing and pelletizing, wherein the step of lubricating is an individual step, namely, lubricant is added after the glue mixing process is finished and the magnetic powder has formed uniform mixture along with the bonder. The ferrite granule prepared by the invention has the characteristics of ferrite/PPS granule and ferrite/PA granule, and has good high temperature resistance and better mechanical property.