| 摘要 |
<p>An average load of 90-220 kg/mm2 is imparted to a finishing-annealed electromagnetic steel plate to form a groove therein, and the resultant steel plate is heat-treated at a temperature of not lower than 750oC to form minute crystals in a strain-introducing portion of the steel plate. These minute crystals enable the value of iron loss to decrease. Such an iron loss-decreasing effect is not lessened even during a strain-removing annealing operation.</p> |
