A NON-ORIENTED ELECTRICAL STEEL SHEET HAVING IMPROVED CORE LOSS AFTER STRESS RELIEF ANNEALING AND A

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PURPOSE : A method for manufacturing a non-oriented electrical steel sheet having improved core loss after stress relief annealing is provided, which increases magnetic density while reducing core loss by coarsening sulfide or nitride with the addition of misch metal. CONSTITUTION : The method includes the steps of reheating a steel slab comprising C <=0.005 wt.%, Si<=2.0 wt.%, Al<=1.0 wt.%, Mn<=1.5 wt.%, P<=0.15 wt.%, S<=0.010 wt.%, N<=0.010 wt.%, a balance of Fe and other inevitable impurities in a temperature range of 1100 to 1300 deg.C followed by hot rolling wherein the weight ratio of misch metal and S+N is 0.5 to 2.0; coiling the hot rolled steel sheet at less than 800 deg.C followed by pickling; cold rolling at a reduction ratio higher than 70 %; final annealing it in the temperature range of 650 to 850 deg.C; and subjecting a stress relief annealing in the temperature range of 700 to 850 deg.C for more than 30 minutes.