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 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 method of manufacturing an inductor element includes preparing an insert member including a winding portion where a conductor is wound in a coil shape. A plurality of preliminary green compacts is obtained by conducting a preliminary compression molding of a granule containing a magnetic powder and a resin at a pressure of 2.5×10.sup.2 to 1×10.sup.3 MPa. The insert member and the plurality of preliminary green compacts are integrated so that a joint interface of the plurality of preliminary green compacts is formed intermittently.

A multilayer magnetic sheet comprises laminate substrates. Each of the laminate substrates is formed in a band shape having a short side and a long side and comprises magnetic strips stacked in layers. The laminate substrates are aligned and arranged in a plate shape in a direction, in which the long sides are adjacent to each other and the short sides extend. The laminate substrates aligned and arranged in the plate shape are stacked in layers in a thickness direction of the laminate substrates. Long side portions of the laminate substrates including the long sides and vicinities of the long sides overlap each other.

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.

A multilayer magnetic sheet comprises a first laminate substrate layer and a second laminate substrate layer, which are stacked in a thickness direction and in each of which laminate substrates each formed in a band shape are arranged in a plate shape such that long sides of the laminate substrates are adjacent to each other, the laminate substrate comprising two or more stacked layers of magnetic ribbons. A direction in which the long sides of the laminate substrates in the second laminate substrate layer extend intersects a direction in which the long sides of the laminate substrates in the first laminate substrate layer extend.

A method for manufacturing a wound magnetic core of a nanocrystalline soft magnetic alloy ribbon, the method including: a first heat treatment step of subjecting a wound magnetic core, which is formed by winding an amorphous soft magnetic alloy ribbon capable of nanocrystallization, to a heat treatment at a temperature that is 300° C. or higher and below a crystallization start temperature, with a first inner shape correction jig for holding the wound magnetic core in a non-circular shape placed in an internal space of the wound magnetic core; and a second heat treatment step of subjecting the wound magnetic core to a heat treatment for nanocrystallization at a temperature equal to or higher than the crystallization start temperature, with the first inner shape correction jig removed and with at least one second inner shape correction jig placed in the internal space of the wound magnetic core, wherein: a cross section of the second inner shape correction jig perpendicular to a direction in which the second inner shape correction jig extends is smaller than a cross section of the first inner shape correction jig perpendicular to a direction in which the first inner shape correction jig extends; and a magnetic field is applied to the wound magnetic core over a partial period of the second heat treatment step.

An Fe-based amorphous alloy ribbon reduced in an iron loss in a condition of a magnetic flux density of 1.45 T is provided. One aspect of the present disclosure provides an Fe-based amorphous alloy ribbon. The Fe-based amorphous alloy ribbon has continuous linear laser irradiation marks on at least one surface. The linear laser irradiation marks are formed along a direction orthogonal to a casting direction of the Fe-based amorphous alloy ribbon. Each linear laser irradiation mark has unevenness on its surface. When the unevenness is evaluated in the casting direction, a difference HL between a highest point and a lowest point in the thickness direction of the Fe-based amorphous alloy ribbon is 0.25 μm to 2.0 μm.

[PROBLEM] To provide a wound magnetic core and a method for manufacturing a wound magnetic core permitting improvement of insulation between ribbon layers in a wound magnetic core at which soft magnetic metal ribbon has been wound to form an annular wound body. [SOLUTION MEANS] 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.

An Fe-based amorphous alloy ribbon reduced in an iron loss in a condition of a magnetic flux density of 1.45 T is provided. One aspect of the present disclosure provides an Fe-based amorphous alloy ribbon. The Fe-based amorphous alloy ribbon has continuous linear laser irradiation marks on at least one surface. The linear laser irradiation marks are formed along a direction orthogonal to a casting direction of the Fe-based amorphous alloy ribbon. Each linear laser irradiation mark has unevenness on its surface. When the unevenness is evaluated in the casting direction, a difference HL between a highest point and a lowest point in the thickness direction of the Fe-based amorphous alloy ribbon is 0.25 μm to 2.0 μm.