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 method for manufacturing a non-circular wound magnetic core composed of a nano-crystallized soft magnetic alloy thin strip comprises: a step for acquiring a multilayer body by winding a soft magnetic alloy thin strip; a step for nano-crystallizing the soft magnetic alloy thin strip by inserting a heat treatment inner peripheral jig to the inner peripheral side of the multilayer body, maintaining the multilayer body in a non-circular shape, and subjecting the multilayer body to a heat treatment; and a step for maintaining the nano-crystallized multilayer body in the non-circular shape by using outer and inner peripheral jigs and impregnating resin between the layers of the multilayer body. The resin impregnation inner and outer peripheral jigs are shaped so as to not contact the inner peripheral surface and/or the outer peripheral surface of the multilayer body at a part where the multilayer body has a large degree of curvature.

Provided is a soft magnetic powder that can produce a dust core having excellent magnetic properties. The soft magnetic powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of Fe.sub.aSi.sub.bB.sub.cP.sub.dCu.sub.eM.sub.f, where the M is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b<6 at %, 0 at %<c≤10 at %, 4 at %<d≤11 at %, 0.2 at %≤e≤0.53 at %, 0 at %≤f≤4 at %, a+b+c+d+e+f=100 at %, a particle size is 1 mm or less, and a median of circularity of particles constituting the soft magnetic powder is 0.4 or more and 1.0 or less.

A soft magnetic alloy including an internal area having a soft magnetic type alloy composition including Fe and Co, a Co concentrated area existing closer to a surface side than the internal area and having a higher Co concentration than in the internal area, and a SB concentrated area existing closer to the surface side than the Co concentrated area and having a higher concentration of at least one element selected from Si and B than in the internal area.

To provide a soft magnetic alloy or the like, from which a magnetic component having a good temperature property of core loss can be obtained. The soft magnetic alloy includes Fe. The soft magnetic alloy includes a crystallite, and an amorphous phase existing around the crystallite. A total area ratio of the crystallite in a cross section of the soft magnetic alloy is 40% or more and less than 60%. An average thickness of the amorphous phase is 3.0 nm or more and 10.0 nm or less. A standard deviation of a thickness of the amorphous phase is 10.0 nm or less.

A method for the production of a metal strip is provided. The method includes providing an amorphous metal strip having a first main surface and a second, opposing main surface. The first and/or the second main surface are treated with a wet-chemical etching process and/or a photochemical etching process.

An Fe-based nanocrystalline alloy is represented by Composition Formula, (Fe.sub.(1-a)M.sup.1a).sub.100-b-c-d-e-gM.sup.2.sub.bB.sub.cP.sub.dCu.sub.eM.sup.3.sub.g, where M.sup.1 is at least one element selected from the group consisting of Co and Ni, M.sup.2 is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, and Mn, M.sup.3 is at least two elements selected from the group consisting of C, Si, Al, Ga, and Ge but necessarily includes C, and 0≤a≤0.5, 1.5<b≤3, 10≤c≤13, 0<d≤4, 0<e≤1.5, and 8.5≤g≤12.