A multilayer block core includes a multilayer block in which nanocrystalline alloy ribbon pieces are layered, the nanocrystalline alloy ribbon pieces having a composition represented by the following Composition Formula (A).
Fe.sub.100-a-b-c-dB.sub.aSi.sub.bCu.sub.cM.sub.d  Composition Formula (A) In Composition Formula (A), each of a, b, c, and d is an atomic percent; the expressions 13.0≤a≤17.0, 3.5≤b≤5.0, 0.6≤c≤1.1, and 0≤d≤0.5 are satisfied; and M represents at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

A method for manufacturing a shielding film is provided. The method includes providing a band of an amorphous soft magnetic alloy; thermally treating the band at a temperature of 500° C. to 600° C. for 1 minute to 1 hour under an N2- or H2-containing atmosphere and under the Earth's magnetic field, thereby creating a nanocrystalline soft magnetic band with a round hysteresis loop; applying an adhesive layer to at least one side of the band; and wherein the band is first applied to a substrate, then thermally treated, after which an adhesive film is applied to the band and, finally, the band is structured by breaking.

A multilayer magnetic sheet comprises laminate substrates each comprising two or more stacked layers of band-shaped magnetic ribbons. The laminate substrates are arranged side by side in a plate shape in a direction in which long sides of the laminate substrates are adjacent to each other and short sides of the laminate substrates extend. The plate shapes each provided by the laminate substrates arranged side by side are stacked in a thickness direction of the laminate substrate. Ten or more layers of the magnetic ribbons are stacked in total. Positions of the long sides of the laminate substrates adjacent to each other in a direction in which the laminate substrates are stacked are different and separated from each other by 0.5 mm or more in the direction in which the short sides extend.

Provided is a soft magnetic alloy including Fe as a main component, in which a slope of an approximate straight line, plotted between cumulative frequencies of 20 to 80% on Fe content in each grid of 80000 grids or more, each of which has 1 nm×1 nm×1 nm, is −0.1 to −0.4, provided that Fe content (atom %) of each grid is Y axis, and the cumulative frequencies (%) obtained in descending order of Fe content in each grid is X axis, and an amorphization ratio X is 85% or more.

A method for producing a magnetic core includes a processing step of giving a desired shape to a strip made of an alloy composition, a heat-treating step of forming bcc-Fe crystals, and then a stacking step of obtaining a magnetic core having a shape. Here, the alloy composition is Fe—B—Si—P—Cu—C and has an amorphous phase as a primary phase. In the heat-treating step, the strip is heated up to a temperature higher than a crystallization temperature of the alloy composition at a high heating rate.

An assembly device for a three-dimensional triangular iron core is provided according to the present application, including iron core driving devices each for driving an iron core to be assembled with adjacent iron cores. There are three iron core driving devices, and each of the iron core driving devices includes an iron core fixing device and a driving assembly for driving the iron core fixing device to move. When the three-dimensional triangular iron core is required to be assembled, firstly, the three iron cores are mounted on the corresponding iron core fixing devices respectively, then the iron core fixing devices are driven by driving assemblies to move toward one another, thereby driving adjacent iron cores to move toward each other until the adjacent iron cores are assembled, and then each two adjacent iron cores are wound and assembled.

Provided is an electromagnetic field shielding plate, etc., in which it is possible to reduce weight while achieving high shielding performance from relatively high-frequency electromagnetic fields. The electromagnetic field shielding plate is configured by layering a permalloy layer 3 comprising a plate or sheet of permalloy, and an amorphous layer 1 comprising an Fe—Si—B—Cu—Nb-based amorphous plate or sheet.

A method is provided for the production of a wound nanocrystalline magnetic core in which a nanocrystalline metal strip made of (Fe.sub.1-aM.sub.a).sub.100-x-y-z-α-βCu.sub.xSi.sub.yB.sub.zM′.sub.αX.sub.β is pre-wound to form a first coil. An insulating foil is provided that is coated with an adhesive on at least one side. An adhesive is applied to the nanocrystalline metal strip to laminate the insulating foil onto the metal strip and thereby to stabilise the metal strip as it is wound off the coil. The laminated nanocrystalline metal strip and the insulating foil are bifilar wound to form a bifilar, layer-insulated coil.

A soft magnetic alloy comprising a main component having a compositional formula of ((Fe.sub.(1−(α+β))X1.sub.αX2.sub.β).sub.(1−(a+b+c))M.sub.aB.sub.bCr.sub.c).sub.1−dC.sub.d, and a sub component including P, S and Ti, wherein X1 is selected from the group Co and Ni, X2 is selected from the group Al, Mn, Ag, Zn, Sn, As, Sb, Bi and rare earth elements, “M” is selected from the group Nb, Hf, Zr, Ta, Mo, W and V, 0.030≤a≤0.14, 0.005≤b≤0.20, 0<c≤0.040, 0≤d≤0.040, α≥0, β≥0, and 0≤α+β≤0.50 are satisfied, when soft magnetic alloy is 100 wt %, P is 0.001 to 0.050 wt %, S is 0.001 to 0.050 wt %, and Ti is 0.001 to 0.080 wt %, and when a value obtained by dividing P by S is P/S, then P/S satisfies 0.10≤P/S≤10.

A nonmagnetic insulating metal oxide powder is made to adhere to a surface of a soft magnetic metal ribbon having an amorphous structure; this is wound in annular fashion and made into a wound body at which the metal oxide powder intervenes between ribbon layers; the wound body is made to undergo heat treatment in a nonoxidizing atmosphere; the wound body is thereafter subjected to treatment for formation of an oxide film in an oxidizing atmosphere adjusted to be at a temperature lower than that at the heat treatment to cause oxidation of the surface of the soft magnetic metal ribbon; and spaces between ribbon layers at the wound body are moreover impregnated with resin and curing is carried out to fuse the metal oxide powder thereto.