| 摘要 |
The present invention relates to a method for preparing nonoriented electric steel plate which is used as iron core of motor, dynamo, small transformer and the like. More specifically, method for preparing nonoriented electric steel plate having superior adhesion of insulating coating is provided. Said method comprises re-heating a steel slave containing C of not more than 0.05% (hereinafter refer to wt%), No more than 3.15% of Si, no more than 1.5% of Mn, no more than 0.15% of P and no more than 1.0% of Al are subject to hot rolling, acid washing with or without annealing of hot rolled plate, and cool rolling and annealing of cool rolled plate, insulating film coating and hardening heating, wherein annealing of cool rolled plate is separated into low temperature annealing and high temperature annealing, and low temperature annealing is carried out in atmosphere of 20 deg. C/65% of dew point, whereas high temperature annealing is carried out in non-oxidized dry atmosphere with dew point of less than 0 deg.C.
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