The invention relates to an inductive component (10) whose soft magnetic core (11) is produced by pouring a casting resin into a mold (1a) filled with a soft magnetic alloy powder and by subsequently hardening the casting resin with the alloy powder in order to form a solid soft magnetic core. Contrary to conventional injection molding methods, this technique prevents the surface insulation of the alloy particles from becoming damaged so that the formation of bulk eddy currents in the resulting soft magnetic cores can be prevented to a large extent. This enables a distinct reduction in the electric loss of the inductive component.

Inductive component and method for the production thereof

A magnet core is required to be particularly dense, made of alloys produced in a rapid solidification process and have a minimal coercitive field strength To achieve these aims, a coarse-grain powder fraction is first produced from an amorphous strip of a soft magnetic alloy In addition, at least one fine-grain powder fraction is produced from a nanocrystalline strip of a soft magnetic alloy The particle fractions are then mixed to produce a multi-modal powder, wherein the particles of the coarse-grain particle fraction have an amorphous structure and the particles of the fine-grain powder fraction have a nanocrystalline structure The multi-modal powder is then pressed to produce a magnet core

Method for the production of magnet cores, magnet core and inductive component with a magnet core

Magnet cores pressed using a powder of nanocrystalline or amorphous particles and a pressing additive should be characterised by minimal iron losses. These particles have first surfaces represented by the original strip surfaces and second surfaces represented by surfaces produced in pulverisation process, the overwhelming majority of these second particle surfaces being smooth cut or fracture surfaces without any plastic deformation, the proportion T of areas of plastic deformation of the second particle surfaces being 0 ≤ T ≤ 0.5.

Magnet core and method for its production

PURPOSE:To obtain a high permeability by constituting a composite soft magnetic material to be used for motor, speaker and head with filament type soft magnetic material bound by the binding agent CONSTITUTION:The soft iron, permalloy and 3% silicon steel are mixed and a mixture is rolled for obtaining filament Thereby, the filament in diameter of 20-100mum can be obtained It is then cut in such a length so that the ratio between length and diameter becomes 2-1,000 Then, a thermosetting resin such as epoxy resin, polyester and phenol is mixed to such filament while the vol% is kept at 50% These are sufficiently kneaded and then compressively molded into the desired shape and is then cured for about two hours at 150 degC Thereby, the material thus obtained is rather expensive than the grain soft magnetic material but assures excellent permeability and a composite soft magnetic material in high cost performance can be obtained

Composite soft magnetic material

PURPOSE:To produce a high tensile strength heat treated steel plate excellent in welding performance characteristic and discrimination characteristic by subjecting a slab of a low carbon steel with a specific composition to hot rolling, to cooling under specified temp. condition, or further to heat treatment under specified conditions after reheating. CONSTITUTION:A slab of a low carbon steel having a composition which contains, by weight, 0.03-0.12% C, =2 kinds among <1.0% Cr, <1.0% Ni, <1.0% Mo, <0.1% V, <0.1% Ti, <0.1% Nb, <0.005% B, <1.0% Cu, and <0.1% rare earth metal element and in which PCM(wt.%) represented by an equation I is regulated to <=0.22% is hot-rolled and, after hot rolling is finished at (Ar3 point + 100 deg.C), the resulting hot rolled plate is successively cooled from a temp. not lower than the Ar3 point at a cooling velocity not lower than air cooling velocity, or further, this hot rolled plate is reheated to a temp. not lower than the Ac3 point, cooled at a cooling velocity not lower than air cooling velocity, heated and held to and at temps. in the two phase region between the Ac3 point and the Ac1 point, cooled at a cooling velocity not lower than air cooling velocity, and successively subjected to tempering treatment at a temp. in the region not higher than the Ac1 point.

Production of high tensile strength heat treated steel plate having low yield ratio and excellent in welding performance characteristics and discrimination characteristic

PURPOSE:To reduce manufacturing cost, by a method wherein, after a mold or a container furnished with required winding is filled with slice-shaped magnetic powder or while being filled therewith, the winding is turned on a DC interminttently and further an insultaing resin is injected to impregnate and solidify said magnetic powder for molding. CONSTITUTION:For instance, the outer periphery of a bottomed cylindrical mold 1 consisting of paramagnetic material is furnished with windings 2 of the required number of turns, said winding 2 is connected with a DC power source 4, and the inside of the mold 1 is filled with slice-shaped magnetic powder 5 to highten filling density by turning the switch 3 on-off several times. Subsequently the fluid insulating resin 6 is injected to impregnate the magnetic powder 5 to be heated and solidified so that the magnetic dust 5 is solidified in the state of being oriented and treated. Thereafter the rod-shaped powder magnetic core 7 can be obtained by taking out from the mold 1. Thereby the automation of each process is simplified thus to reduce manufacturing cost.

Kanji Matsui

Papers

Manufacture of dust magnetic core and dust magnetic core coil