A METHOD FOR MANUFACTURING GRAIN-ORIENTED Si-STEEL SHEET HAVING SUPERIOR MAGNETIC PROPERTY

摘要

The present invention relates to a method for producing a grain-oriented silicon steel sheet, in the production of grain-oriented silicon steel sheet, by aligning the grain boundary segregation of phosphorus, tin, boron and nitrogen effectively to suppress the normal growth of grains, to produce a grain-oriented silicon steel sheet excellent in magnetic properties It is an object to provide a method for producing a stable and low cost.;In the present invention, Si: 2.0 to 4.0%, C: 0.07% or less, Mn: 0.01% or more, P: 0.03 to 0.06%, Sn: 0.06 to 0.12%, B: 0.0005 to 0.0030%, S: 0.007 % Or less, Al: 0.01% or less, after reheating the steel slab composed of the remaining Fe and other unavoidable impurities, hot rolling and pickling, and cold rolling twice, including once cold rolling or intermediate heat treatment, are made of cold rolled steel sheet In the method for producing a grain-oriented silicon steel sheet by nitrogen enrichment at the same time with the decarburization in the atmosphere containing ammonia or by incubating the nitrogen after decarburization, the final heat treatment,;Technical aspect of the present invention relates to a method for producing a grain-oriented silicon steel sheet having excellent magnetic properties, characterized in that the total nitrogen in the steel is adjusted to 150 ppm to 250 ppm during the nitrogen enrichment treatment.