STRIP CORE Russian patent published in 2024 - IPC H01F27/245 H01F1/147 C21D8/12 C22C38/02 

FIELD: electrical engineering.

SUBSTANCE: strip core includes a rectangular strip core body in a side view, in which the strip core body has a portion in which anisotropic electrical steel sheets, in which the first flat portions and the corner portions alternate continuously in the longitudinal direction, and an angle formed by the first two adjacent each other with each other flat parts, with each of the corner parts between them, is 90°, are stacked in a sheet thickness direction, and has a substantially rectangular laminated structure in side view, in which each of the corner portions has two or more curved portions having a curved shape in side view of the anisotropic electrical steel sheets, and the second flat portion between adjacent curved parts, and the sum of the bending angles of the curved parts in one corner part is 90°, in which each curved part in side view has an internal radius of curvature r equal to 1-5 mm. Sheets of anisotropic electrical steel have a chemical composition containing, wt.%, Si: C - up to 0.0050, not including 0, Si: 2.0-7.0, Fe and impurities are the rest and have a texture oriented in the Goss orientation, and in which at least one of the two or more curved parts present in at least one corner part satisfies the following equations (1 ) - (3): Tave≤ 40 nm (1), (To – Tu)/Tave≤ 0.5 (2), Tave (To – Tu)≤ 240 nm² (3), where the thickness T (nm) of the intermediate layer provided on the surface of the main steel sheet of the anisotropic electrical steel sheets is measured at a plurality of positions of the regions of the first and second flat parts adjacent to the curved parts, the average value of the thickness T (nm) the intermediate layer is denoted as Tave (nm), the maximum thickness is denoted as Tmax (nm), the minimum thickness is denoted as Tmin (nm), the average of the data where T>Tave is denoted as To (nm), and the average of the data where T <Tave, denoted by Tu, (nm).

EFFECT: strip core produced by bending steel sheets in advance so that a relatively small bending area with a radius of curvature of 5 mm or less is formed, and laminating the bent steel sheets to form the strip core, thereby minimizing unintended performance degradation.

4 cl, 5 tbl, 9 dwg