11 results about "Sendust" patented technology

The invention relates to the technical field of magnetic materials, in particular to a low-loss high-direct-current-bias soft magnetic composite material and a preparation method and application thereof.The low-loss high-direct-current-bias soft magnetic composite material is composed of nanometer titanium dioxide and iron-silicon-aluminum alloy powder; the nano titanium dioxide and the iron-silicon-aluminum alloy powder are combined in a core-shell structure form, the iron-silicon-aluminum alloy powder is used as a core, and the outer side of the iron-silicon-aluminum alloy powder is coated with a nano titanium dioxide shell. The soft magnetic composite material with low loss and high direct current bias has high direct current bias performance, relatively high magnetic conductivity and relatively low high-frequency loss, meanwhile, the preparation process of the soft magnetic composite material is simple, the prepared material has stable performance and very high direct current bias performance, and the soft magnetic composite material can be used for industrial batch production and has a wide application prospect.

A dust core according to the present invention is characterized by comprising a granulated powder in which 2.0 to 4.0 mass% of a binder containing an acrylic resin as a main component is added to a magnetic alloy powder. The pH (hydrogen ion index) of the binder is preferably 6.0 to 8.0. The glass transition point of the binder is preferably from -5°C to lower than 25°C. The magnetic alloy powder is preferably any one of sendust powder, an amorphous alloy powder, or a nanocrystalline alloy powder.

The present invention discloses a MHz-level low-loss sendust magnetic powder core and a preparation method thereof, comprising the following steps: (1) insulation coating: adding a coating agent, zinc acetate solution, to sendust alloy powder, stirring evenly, then frying on a heating furnace to dry, cooling, forming a passivated powder, then adding a binder, stirring evenly, heating and frying to dry, and cooling; (2) pressing and molding: adding a release agent to the coated powder, stirring evenly, and pressing into a green part; (3) heat treatment: annealing the green part in step (2) under a protective atmosphere, cooling, and obtaining a MHz-level low-loss sendust magnetic powder core. This technical solution creatively uses zinc acetate as a coating agent to passivate and coat sendust powder, thereby increasing its operating frequency to the high-frequency MHz range while maintaining a relatively low loss. At the same time, it also has a high effective magnetic permeability and magnetic flux density BS, suitable for MHz working conditions, and stable performance.

The invention discloses ultrathin iron-silicon-aluminum flaky powder and a preparation method thereof, and particularly relates to the field of metal and alloy powder preparation. The method comprises the steps that firstly, an alloy material containing iron, silicon and aluminum is melted into alloy steel liquid through medium-frequency induction or electric arc induction, the steel liquid flows out through a flow limiting opening with the diameter being 3-8 mm, and gas atomization is conducted on the steel liquid through high-pressure nitrogen / argon; spraying atomized molten steel drops to the surface of a copper roller or a copper disc rotating at a high speed, and carrying out quenching solidification to form flaky powder; finally, the flaky powder is subjected to annealing treatment under the protection of nitrogen / argon; and grading and screening according to the granularity requirement to finally obtain the ultrathin iron-silicon-aluminum sheet-shaped powder. According to the preparation method, the thickness of the flaky powder can be further reduced, and the flake diameter of the flaky powder is increased, so that the length-diameter ratio is increased, and the high-frequency magnetic conductivity is further improved.

The fasteners for chain-type accessories can be easily removed when needed, and the magnetic force is not transmitted to the surrounding area on the magnetic surface where it is not originally needed. This prevents magnetic clasps from attracting each other when multiple chain-type accessories are displayed side by side on display shelves, etc., and also prevents magnetic clasps from attracting to bag fittings when a hand is placed in a bag. [Solution] A fastener for a chain-like accessory is provided with a pair of magnets 2 at the fasteners at both ends of the chain 3 of the chain-like accessory, and the surfaces other than the joining surface 2a of the magnets are surrounded by a magnetic shielding material 4. The magnetic shielding material is made of iron, permalloy, sendust, or silicon copper, and a gap 5 is interposed between the magnet and the magnetic shielding material.

To provide a powder magnetic core that uses a magnetic alloy powder and has excellent radial crushing strength and moldability, and a method for manufacturing the same.SOLUTION: A powder magnetic core according to the present invention is made of granulated powder obtained by adding 2.0 mass% or more and 4 mass% or less of a binder whose main component is acrylic resin to a magnetic alloy powder. The pH (hydrogen ion exponent) of the binder is preferably 6 or more and 8 or less. The glass transition point of the binder is preferably -5°C or more and less than 25°C. The magnetic alloy powder is preferably any one of sendust powder, amorphous alloy powder, and nanocrystalline alloy powder.SELECTED DRAWING: Figure 1

The present invention belongs to the field of soft magnetic functional materials, and specifically relates to a low-loss, high-overlap sendust magnetic powder core and a preparation method thereof, comprising the following steps: preparing a coating agent, passivating the coated powder, bonding and lubricating, and pressing and annealing. This method is based on the hydrolysis characteristics of metasilicic acid and the hydrolysis-promoting effect of an alkaline catalyst to prepare nanoporous silica as a coating agent. At the same time, the etching effect of alkaline substances on silica can effectively increase the specific surface area of nanoporous silica and enhance the bonding strength with sendust powder; the vacuum calcination treatment not only removes residual reagents, but also promotes the full thermal decomposition of metasilicic acid into silica for in-situ coating, and stabilizes its lattice structure. The coating layer of the low-loss, high-overlap sendust magnetic powder core of the present invention is firmly bonded, thin and uniform in thickness, and has a stable and dense structure, which can effectively reduce the hysteresis loss of the sendust magnetic powder core, improve DC bias performance, and avoid the increase of eddy current loss.

According to this disclosure, a means may be provided for an electromagnetic wave shielding laminate film that is less prone to breakage when bonded to an object having a bent portion, and that achieves a high electromagnetic wave shielding effect when the object has a bent portion. [Solution] This disclosure relates to an electromagnetic wave shielding laminate film comprising a resin layer and a conductive layer, wherein the resin layer contains at least one compound selected from the group consisting of elastomers and cellulosic polymers and a magnetic material, the conductive layer contains a conductor, and the magnetic material comprises at least one selected from the group consisting of permalloy, ferrite and sendust, and the elongation at break at 170°C is 110% or more and 200% or less.

The invention relates to iron-silicon-aluminum magnetic powder core forming equipment and a process thereof. Comprising a fixing plate, a supporting plate is arranged above the fixing plate through a spring rod, and a mounting plate and a sliding plate are sequentially arranged above the supporting plate. An extrusion device is arranged on the fixing plate and comprises an extrusion mechanism and a vibration mechanism. According to the device, the following problems existing in the forming process of the sendust material in the prior art can be solved: firstly, by arranging the vibration mechanism, before extrusion forming is carried out on sendust magnetic powder, the interior and exterior of the sendust magnetic powder are leveled through vibration, and the particle distribution uniformity of the sendust magnetic powder is greatly improved; and secondly, the multiple sets of mold rings are arranged and matched with the extrusion device, the iron-silicon-aluminum magnetic powder of the multiple mold rings can be extruded and formed at the same time, compared with a traditional single-piece production mode that only a single mold is used, the multiple sets of mold rings can extrude multiple magnetic powder blanks at the same time, and the overall production period is greatly shortened.

The utility model provides an iron-silicon-aluminum inductor, which relates to the technical field of inductors and comprises an iron-silicon-aluminum shell and an iron-silicon-aluminum cover, a placing cavity is arranged in the iron-silicon-aluminum shell, a cylinder is arranged in the center of the interior of the placing cavity, fixing components are arranged on two sides of the periphery of the cylinder, and the fixing components are arranged on the periphery of the cylinder. A wire spool is arranged in the containing cavity and located on the periphery of the fixing assembly in a sleeved mode, a copper wire is wound on the wire spool, and by winding the copper wire on the wire spool, when the iron-silicon-aluminum inductor is damaged and the internal copper wire needs to be replaced, the wire spool is taken out, a new wire spool and a new copper wire on the wire spool are replaced, or the copper wire on the wire spool is detached, and then the iron-silicon-aluminum inductor is replaced. And the new copper wire is manually wound on the wire spool, so that the operation is simple, the manual operation is convenient, the automatic production can be realized, and the practicability is high.

A highly weather-resistant low-frequency radar absorber and its preparation method. The low-frequency radar absorber is composed of nickel-zinc ferrite as a main component, doped with small amounts of sendust and graphene. The nickel-zinc ferrite content is ≥90wt%, the sendust content is 6-8wt%, and the graphene content is 1-2wt%. The sendust is a specially processed flaky sendust, i.e., the sendust is ball-milled with alcohol to a particle size of 20±10μm. The present invention also includes a preparation method for the low-frequency radar absorber. The low-frequency radar absorber of the present invention has strong weather resistance, good radar absorption performance, and is thin in thickness. Its preparation method is simple.