| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a steel sheet capable of being reduced in deterioration of magnetic properties after being sheared even when the electromagnetic steel sheet has a thickness of 0.220 mm or less, in the electromagnetic steel sheet used for a large transformer of a size as large as several meters. <P>SOLUTION: The electromagnetic steel sheet has a composition containing, by mass, 0.005% or less C, 1.0-8.0% Si, and 0.005-1.0% Mn, further 10-50 mass ppm, in total, of one or more elements selected from among Nb, Ta, V and Zr, with the balance consisting of Fe and inevitable impurities, and is characterized in that at least 10% of each content of the Nb Ta, V and Zr is present in a precipitated state, the precipitated objects have diameters (circle-equivalent diameters) of 0.02-3 μm on the average, the number of intervening objects having diameters of 10 μm or more is less than 1 piece/mm<SP POS="POST">2</SP>, and the average grain diameter of the secondary recrystallization grains in the steel sheet is 5 mm or more. <P>COPYRIGHT: (C)2012,JPO&INPIT |
