Patent ID: 6241829
Filing Date: 2001-06-05
Classification: C21D,C22C,C23C,H01F

Abstract:
A method for producing a silicon steel sheet comprising the steps of:preparing a steel slab containing C in an amount of 0.01 wt. % or less and Si in an amount of from 4 to 10 wt. %;hot rolling the steel slab to produce a hot rolled steel sheet;descaling the hot rolled steel sheet;cold rolling the descaled hot rolled steel sheet to produce a cold rolled steel sheet; andsubjecting the cold rolled steel sheet to a final annealing treatment at a temperature of at least 700.degree. C. wherein the cooling speed in the annealing treatment is 5.degree. C./sec. or more in a temperature range of from 700.degree. C. to 300.degree. C. to produce a silicon steel sheet having grain boundaries and carbides and wherein carbides which are precipitated on the grain boundaries have an area of 20% or less of the area of the grain boundaries.