GRAIN-ORIENTED ELECTRICAL STEEL SHEET, AND METHOD FOR PRODUCING SAME

摘要

The present invention provides a grain oriented electrical steel sheet that has been subjected to magnetic domain refining treatment by means of electron beam irradiation and exhibits excellent low-noise properties when assembled as an actual transformer, in which tension exerted on the steel sheet by the forsterite film is 2.0 MPa or higher both in a rolling direction and a direction transverse (perpendicular) to the rolling direction, and a ratio of an irradiation pitch in a thermal strain introduced region (B) to a spot diameter (A) on an electron beam irradiation surface satisfies a relation: 0.5 ‰¤ B/A ‰¤ 5.0.