GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a method for improving furthermore magnetic properties of a grain-oriented electrical steel sheet by heightening tension of a surface film comprising a base coating mainly composed of forsterite and a phosphate-based overcoating coated thereon.SOLUTION: The ratio [P(K)/P(Na)] between K intensity and Na intensity of an X-ray fluorescence analysis of a steel sheet surface is in the range of 1.0 or higher and 8.0 or lower.