A wound core equipped with a laminated body including plural electrical steel sheets stacked in a ring shape in side view. The laminated body includes plural bent portions, and plural block-shaped portions at positions between adjacent bent portions. At least one bent portion among the plural bent portions is a high stacking factor bent portion, wherein a stacking factor of the electrical steel sheets at the high stacking bent portion is higher than an average stacking factor of the steel sheets at the plural block-shaped portions.

An alloy having a formula Fe.sub.aCo.sub.bNi.sub.cCu.sub.dM.sub.eSi.sub.fB.sub.gX.sub.h is provided. M is at least one of V, Nb, Ta, Ti, Mo, W, Zr, Cr, Mn and Hf; a, b, c, d, e, f, g are in at. %; X denotes impurities and optional elements P, Ge and C; and a, b, c, d, e, f, g, h satisfy the following:
0≤b≤4,
0≤c<4,
0.5≤d≤2,
2.5≤e≤3.5,
14.5≤f≤16,
6≤g≤7,
h<0.5, and
1≤(b+c)≤4.5, where a+b+c+d+e+f+g=100. The alloy has a nanocrystalline microstructure, a saturation magnetostriction of |λ.sub.s|≤1 ppm, a hysteresis loop with a central linear part, and a permeability (μ) of 10,000 to 15,000.

Implementations described herein provide systems and methods for wireless charging. In one implementation, a portable electronic device comprises a housing, a planar inductor coil, and a ferromagnetic shield. The planar inductor coil is disposed in the housing and comprises a conductive wire wound a plurality of turns about a center point and in increasing radii. The ferromagnetic shield is disposed in the housing and overlaps the planar inductor coil. The ferromagnetic shield comprises a first layer comprising a first plurality of iron-based nanocrystalline ribbons arranged in adjacent rows along a first direction and a second layer comprising a second plurality of iron-based nanocrystalline ribbons overlapping the first layer. The second plurality of iron-based nanocrystalline ribbons is arranged in adjacent rows along a second direction different from the first direction.

An amorphous metal ribbon includes a plurality of laser irradiation mark rows each including a plurality of laser irradiation marks arranged in a row, in which when a distance between the laser irradiation mark rows that are adjacent to each other is set as d1, a distance between the laser irradiation marks in the laser irradiation mark row is set as d2, a diameter of the laser irradiation mark is set as d3, and a number density D of the laser irradiation marks is set as (1/d1)×(1/d2), the number density D of the laser irradiation marks is 0.05 pieces/mm.sup.2 or more and 0.50 pieces/mm.sup.2 or less, and when an area occupancy rate A of the laser irradiation marks is set as D×(d3/2).sup.2×π×100, the area occupancy rate A of the laser irradiation marks is 0.0035% or more and 0.040% or less.

An amorphous metal ribbon includes a plurality of laser irradiation mark rows each including a plurality of laser irradiation marks arranged in a row, in which when a distance between the laser irradiation mark rows that are adjacent to each other is set as d1, a distance between the laser irradiation marks in the laser irradiation mark row is set as d2, a diameter of the laser irradiation mark is set as d3, a depth of the laser irradiation mark is set as d4, and a volume occupancy rate V of the laser irradiation marks is set as (1/d1×d3×d4)×(1/d2)×100, the volume occupancy rate V of the laser irradiation marks is 0.00057% or more and 0.010% or less.

An amorphous metal ribbon includes a plurality of laser irradiation mark rows each including a plurality of laser irradiation marks arranged in a row, in which when a distance between the laser irradiation mark rows that are adjacent to each other is set as d1, a distance between the laser irradiation marks in the laser irradiation mark row is set as d2, a diameter of the laser irradiation mark is set as d3, a depth of the laser irradiation mark is set as d4, and a volume occupancy rate V of the laser irradiation marks is set as (1/d1×d3×d4)×(1/d2)×100, the volume occupancy rate V of the laser irradiation marks is 0.00057% or more and 0.010% or less.

A manufacturing method for a laminated iron core includes conveying a sheet steel strip in an intermittent manner in a lift up state, with upward movement of the strip being limited by a guiding member provided on a lower holder; punching an outer shape of each iron core laminae; and applying adhesive agent to a surface of the strip before the punching. The adhesive agent is applied in a state in which a pilot pin is inserted in a pilot hole of the strip and when the strip is about to be pressed against or is being pressed against the die plate by a stripper provided on an upper holder. After application of the adhesive agent, the strip is returned to the lift up state by raising the upper holder, with a lifter and the stripper plate being in abutment with the lower and upper surfaces of the strip, respectively.

A manufacturing method for a laminated iron core includes conveying a sheet steel strip in an intermittent manner in a lift up state, with upward movement of the strip being limited by a guiding member provided on a lower holder; punching an outer shape of each iron core laminae; and applying adhesive agent to a surface of the strip before the punching. The adhesive agent is applied in a state in which a pilot pin is inserted in a pilot hole of the strip and when the strip is about to be pressed against or is being pressed against the die plate by a stripper provided on an upper holder. After application of the adhesive agent, the strip is returned to the lift up state by raising the upper holder, with a lifter and the stripper plate being in abutment with the lower and upper surfaces of the strip, respectively.

An inductor includes a first magnetic body having a toroidal shape and having a ferrite; and a second magnetic body configured to be different from the first magnetic body and including a metal ribbon, wherein the second magnetic body includes an outer magnetic body disposed on an outer circumferential surface of the first magnetic body and an inner magnetic body disposed on an inner circumferential surface of the first magnetic body, and each of the outer magnetic body and inner magnetic body is wound in a plurality of layers in a circumferential direction of the first magnetic body.

An inductor includes a first magnetic body having a toroidal shape and having a ferrite; and a second magnetic body configured to be different from the first magnetic body and including a metal ribbon, wherein the second magnetic body includes an outer magnetic body disposed on an outer circumferential surface of the first magnetic body and an inner magnetic body disposed on an inner circumferential surface of the first magnetic body, and each of the outer magnetic body and inner magnetic body is wound in a plurality of layers in a circumferential direction of the first magnetic body.