Wound core

A wound core including a substantially rectangular wound core main body in a side view,

• wherein the wound core main body includes a portion in which grain-oriented electrical steel sheets in which first planar portions and corner portions are alternately continuous in a longitudinal direction and an angle formed by two first planar portions adjacent to each other with each of the corner portions therebetween is 90° are stacked in a sheet thickness direction and has a substantially rectangular laminated structure in a side view,
• wherein in a side view of the grain-oriented electrical steel sheets, each of the corner portions has two or more bent portions having a curved shape and a second planar portion between the adjacent bent portions, and a sum of bent angles of the bent portions present in one corner portion is 90°,
• wherein the two or more bent portions in a side view has an inner radius of curvature r of 1 mm or more and 5 mm or less,
• wherein the grain-oriented electrical steel sheets have a chemical composition containing,
• in mass %,
• Si:
• 2.0 to 7.0%, with the remainder comprising Fe and impurities, and
• have a texture oriented in the Goss orientation, and
• wherein in one or more of the first planar portion and the second planar portion adjacent to at least one of the bent portions, an existence frequency of subgrain boundaries in a region within 9 mm in a direction perpendicular to a boundary with the at least one of the bent portions satisfies the following Formula (1):
• (Nac+Nal)/Nt≥0.010 (1)
• where, when a plurality of measurement points are arranged at intervals of 2 mm in a direction parallel to and direction vertical to the bent portion boundary in the region of the one or more of the first planar portion or the second planar portion adjacent to the at least one of the bent portions, Nt in Formula (1) is a total number of line segments connecting two adjacent measurement points in the parallel direction and the vertical direction,
• Nac in Formula (1) is the number of line segments at which subgrain boundaries are able to be identified among the line segments direction parallel to the bent portion boundary, and Nal in Formula (1) is the number of line segments at which subgrain boundaries are able to be identified among line segments in a direction perpendicular to the bent portion boundary.