Metal laminate cores can be assembled with laser pin welding through a thickness of a first laminate into a second laminate and successively laser pin welding a plurality of second laminates, ending with a third laminate to form the core stack. The laser pin welds are located within an outer perimeter of one or more of the laminates. Such laminated cores are often utilized in electrical motors, generators, transformers, lighting and other applications. The laser pin welds can be selectively provided under the control of a processor to index about the parts and/or change in intensity or even skip certain parts so as to be able to begin and end cores for some embodiments while also facilitating manual and/or automated stacking/welding embodiments and/or relative rotation of the cores.

A non-oriented electrical steel sheet has a predetermined chemical composition. The chemical composition satisfies (2×[Mn]+2.5×[Ni]+[Cu])−([Si]+2×[sol.Al]+4×[P])≥1.50%. In a case where Ahkl-uvw represents the area ratio of crystal grains in an {hkl}<uvw> orientation to the entire visual field when a plane at a depth of ½ of a sheet thickness from a surface parallel to a rolled surface is measured by SEM-EBSD, A411-011 is 15.0% or more, and the average grain size is 50 μm to 150 μm.

A soft magnetic alloy containing 1% by atom or more and 10% by atom or less of one or more elements M1 selected from Ga and Ge, substantially containing no Si, and containing Fe and unavoidable impurities as a balance.

A grain-oriented electrical steel sheet according to the present invention has a steel sheet surface provided with grooves and includes two or more broken lines including the grooves having a length of 5 to 10 mm on a straight line intersecting a rolling direction on the steel sheet surface. In each of the broken lines including the grooves, the grooves are arranged at equal intervals, and a ratio of the length of the groove to a length of a non-groove is in a range of 1:1 to 1.5:1.

A hybrid transformer core flGf includes comprises columns (21 23) of grain-oriented steel and yokes . A yoke includes a plurality of second plies including sheets of amorphous steel adhered to each other by an adhesive coating on an outer peripheral area of major faces of the sheets of amorphous steel.

A hybrid transformer core flGf includes comprises columns (21 23) of grain-oriented steel and yokes . A yoke includes a plurality of second plies including sheets of amorphous steel adhered to each other by an adhesive coating on an outer peripheral area of major faces of the sheets of amorphous steel.

In a magnetic core including a core assembly formed of multiple arranged thin strip blocks, each of the thin strip blocks has a structure that multiple nanocrystalline thin strips having a bcc-Fe phase as a main phase are laminated one above another, and an iron loss in the nanocrystalline thin strip positioned at a center of the thin strip block in a thickness direction thereof is lower than an iron loss in the nanocrystalline thin strip positioned in a surface layer of the thin strip block. The nanocrystalline thin strip may be a heat-treated product of an amorphous thin strip made of an amorphous alloy material, and the thin strip block may include a fixedly joined portion in which the nanocrystalline thin strips adjacent to each other in a lamination direction are fixedly joined together.

In a magnetic core including a core assembly having a structure that multiple thin strip blocks are arranged, the thin strip blocks being formed of multiple laminates of nanocrystalline thin strips made of a nanocrystal-containing alloy material, the thin strip block includes a fixedly joined portion in which the nanocrystalline thin strips adjacent to each other in a lamination direction are fixedly joined together. The fixedly joined portion may include side surfaces of the nanocrystalline thin strips and may be a laser welded portion.

It has been difficult to manufacture a large-capacity transformer having a laminated iron core structure using an amorphous alloy material easily. A laminated iron core structure includes a laminated iron core configured by aligning a plurality of laminated iron core blocks each configured by laminating iron core materials in a direction different from a lamination direction, a first frame extending along an outer periphery of the laminated iron core and a partition plate arranged between the plurality of laminated iron core blocks.

This coating composition for an electrical steel sheet is a coating composition for an electrical steel sheet containing an epoxy resin, a high-temperature curing agent, and inorganic fine particles, wherein a content of the high-temperature curing agent with respect to 100 parts by mass of the epoxy resin is 5 to 30 parts by mass, wherein the inorganic fine particles are one or more selected from metal hydroxides, metal oxides that react with water at 25° C. to become metal hydroxides and silicate minerals having a hydroxyl group, wherein the volume average particle diameter of the inorganic fine particles is 0.05 to 2.0 μm, wherein a content of the epoxy resin with respect to a total mass of the coating composition for an electrical steel sheet is 45 mass % or more, and wherein a content of the inorganic fine particles with respect to 100 parts by mass of the epoxy resin is 1 to 100 parts by mass.