| 摘要 |
PROBLEM TO BE SOLVED: To provide a grain oriented magnetic steel sheet in which the improvement of iron loss is efficiently maximized by a laser irradiation, the increase in magnetostriction is restrained to the utmost, the ferrite of steel sheet is not exposed in a laser irradiated part and re-coating is not needed. SOLUTION: This grain oriented magnetic steel sheet excellent in magnetic property is obtained by irradiating laser beams at the paired positions on both surfaces of the steel sheet to form a narrow closure domain. In this case, the width of the closure domain in a rolling direction is less than 0.3 mm, and the displacement amount of the paired closure domain positions on both surfaces in the rolling direction is within the width of the closure domain in the same direction. Further, the trace of laser irradiation exists on the surface of steel sheet, or the ferrite of steel sheet is not exposed in the laser irradiated part of the steel sheet surface. |
