| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a non-oriented electrical steel sheet having a magnetic flux density B50 of not less than 1.60 T, a core loss W<SB>10/400</SB>of not higher than 23 W/kg and a fatigue limit of 330 MPa or more and being free from problems in rotor manufacturing. <P>SOLUTION: The non-oriented electrical steel sheet has a composition consisting of, by mass, ≤4% Si, 0.05 to 5% Mn, ≤3% Al and the balance Fe with inevitable impurities. In this steel sheet, a region in which hardness is ≥1.3 times the Vickers hardness at the central part of the sheet thickness ranges between 5 and 50μm from the surface of the steel sheet toward the central part of the sheet thickness. <P>COPYRIGHT: (C)2008,JPO&INPIT |
