The present disclosure relates to a magnetic multilayer composite that may include a core substrate layer, an outer magnetic layer overlying a first surface of the core substrate layer, and an inner magnetic layer underlying a second surface of the core substrate layer. The composite may include a magnetic volume ratio V.sub.M/V.sub.S of at least about 0.005, where V.sub.M is equal to the total volume of magnetic material in the composite and V.sub.S is the total volume of substrate. The composite may further include a permeability rating (X, Y), where the permeability rating (X, Y) is equal to a peak point (X, Y) along a plot of the imaginary part of magnetic permeability (μ″) of the composite plotted as a function of frequency, where X is within the range of 10 MHz to 10 GHz, and Y is greater than 100.

A method includes producing an amorphous precursor to a nanocomposite, the amorphous precursor comprising a material that is substantially without crystals not exceeding 20% volume fraction; performing devitrification of the amorphous precursor, wherein the devitrification comprises a process of crystallization; forming, based on the devitrification, the nanocomposite with nano-crystals that contains an induced magnetic anisotropy; tuning, based on one or more of composition, temperature, configuration, and magnitude of stress applied during annealing and modification, the magnetic anisotropy of the nanocomposite; and adjusting, based on the tuned magnetic anisotropy, a magnetic permeability of the nanocomposite.

A method for the heat treatment of at least one sheet made of a soft magnetic alloy is provided. At least one sheet made of a soft magnetic alloy is heat treated at a temperature of between 400° C. and 1300° C. for a period of at least 15 minutes in a hydrogen-containing atmosphere. During this heat treatment the gas pressure level of the hydrogen-containing atmosphere is changed at least twice.

A dust core contains a powder of a crystalline magnetic material powder and a powder of an amorphous magnetic material. The sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 83 mass percent or more. The mass ratio of the content of the crystalline magnetic material powder to the sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 20 mass percent or less. The median diameter D50a of the amorphous magnetic material powder is greater than or equal to the median diameter D50c of the crystalline magnetic material powder. A 10% cumulative diameter D10a in a volume-based cumulative particle size distribution of the amorphous magnetic material powder is 9.5 μm or less.

A dust core contains a powder of a crystalline magnetic material powder and a powder of an amorphous magnetic material. The sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 83 mass percent or more. The mass ratio of the content of the crystalline magnetic material powder to the sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 20 mass percent or less. The median diameter D50a of the amorphous magnetic material powder is greater than or equal to the median diameter D50c of the crystalline magnetic material powder. A 10% cumulative diameter D10a in a volume-based cumulative particle size distribution of the amorphous magnetic material powder is 9.5 μm or less.

A powder core includes a compact including a soft magnetic powder, and an outer coating of the compact. The outer coating contains polyethersulfone. An electric or electronic component including the powder core, and an electric or electronic device having the electric or electronic component mounted therein are also provided.

A specific depth at which a concentration of Fe reaches 10 at % is 18 nm or more and 500 nm or less from the first surface, and from the first surface to the specific depth, the concentration of Fe is less than 10 at %, and a positive increase region is present in which the concentration of Fe increases with a substantially positive concentration gradient, in a case where the concentration of Fe is measured in a depth direction from a first surface of a ribbon.

Provided a soft magnetic alloy ribbon containing Fe and B. Convex portions having an average convex portion height of 7 nm to 130 nm are present on an alloy surface.

A magnetic film includes iron and copper distributed between opposing first and second major surfaces of the magnetic film. The copper has a first atomic concentration C1 at a first depth d1 from the first major surface and a peak second atomic concentration C2 at a second depth d2 from the first major surface, d2>d1, C2/C1≥5.

A coupled inductor has two coils made by film processes, wherein a first coil is disposed on a top surface of a magnetic sheet and a second coil is disposed on a bottom surface of the magnetic sheet, for controlling the variations of the gap between the two coils in a smaller range.