| 摘要 |
<p>A method for manufacturing a grain-oriented electrical steel sheet with excellent magnetic properties is provided to enlarge grains of a first recrystallized steel sheet by controlling the content of nitrogen contained in a base steel composition, and uniformize and enlarge sizes of first recrystallized grains by controlling the content of sulfur contained in the base steel composition to a very low value and simultaneously performing decarburization and nitriding of a steel sheet. In a method for manufacturing a grain-oriented electrical steel sheet by reheating a slab for the grain-oriented electrical steel sheet comprising, by weight percent, 2.0 to 7.0% of Si, 0.015 to 0.035% of acid soluble Al, 0.20% or less(excluding 0%) of Mn, and the balance of Fe and other inevitable impurities to a temperature of 1100 to 1200 deg.C, hot-rolling the reheated slab, skipping or performing annealing of a hot-rolled steel sheet, cold-rolling the non-annealed or annealed steel sheet, performing simultaneous decarburizing-nitriding annealing of the cold-rolled steel sheet, and subjecting the simultaneous decarburizing-nitriding annealed steel sheet to second recrystallization annealing, a method for manufacturing a grain-oriented electrical steel sheet with excellent magnetic properties comprises adding N and S in the amount of not higher than 0.003%(excluding 0%) by weight into the slab in the slab reheating step such that AlN and MnS are generated and subjected to complete solid solution. The simultaneous decarburizing-nitriding annealing of the cold-rolled steel sheet is carried out at a temperature of 800 to 900 deg.C in the atmosphere of mixed gas of ammonia, hydrogen and nitrogen.</p> |
