A METHOD FOR MANUFACTURING GRAIN-ORIENTED Si-STEEL SHEET WITH HIGH MAGNETIC PROPERTY

摘要

PURPOSE: A method for manufacturing grain-oriented Si-steel sheets with high magnetic property is provided, in which a specific amount of Sb is contained in steel at steelmaking step and Sb and N is effectively segregated along grain boundaries by enriching a specific amount of N in steel after cold rolling. CONSTITUTION: The method includes the steps of hot rolling a steel slab comprising Si 2.0-4.0 wt.%, C 0.07 wt.% or less, Mn 0.01 wt.% or less, P 0.02 wt.% or less, Sb 0.01-0.12 wt.%, Al 0.015 wt.% or less, a balance of Fe and other inevitable impurities; primary cold rolling, process annealing, secondary cold rolling; decarburization annealing and nitrogen-enrichment to control total amount of N within 150-250ppm.