| 摘要 |
<p>A grain-oriented electromagnetic steel sheet comprising an electromagnetic steel sheet with recesses, subdividing magnetic domains, formed by irradiating the surface of the electromagnetic steel sheet with a pulsed laser beam, wherein rows of recesses provided along the widthwise direction of the steel sheet are provided at predetermined spacings in the rolling direction and the recesses satisfy the following requirements: length of recesses in rolling direction, dl: 50 mu m ≤ dl ≤ 300 mu m, length of recesses in widthwise direction of sheet, dc: 100 mu m ≤ dc ≤ 3000 mu m, provided that dl/dc < 1 depth of recess, d: 10 mu m ≤ d ≤ 30 mu m, row pitch of recess in rolling direction, Pl: 3 mm ≤ P1 ≤ 10 mm, and pitch of recesses in widthwise direction of sheet, Pc: dc - 50 mu m ≤ Pc ≤ dc + 50 mu m, and a process for producing a grain-oriented electromagnetic steel sheet, characterized by focusing a pulsed laser beam in a rectangular or elliptical form on the surface of an electromagnetic steel sheet to form the recesses.</p> |
