GRAIN-ORIENTED ELECTRICAL STEEL SHEET, METHOD FOR MANUFACTURING GRAIN-ORIENTED ELECTRICAL STEEL SHEET, AND ANNEALING SEPARATOR UTILIZED FOR MANUFACTURE OF GRAIN-ORIENTED ELECTRICAL STEEL SHEET

摘要

Grain-oriented electrical steel sheet excellent in magnetic properties and excellent in adhesion of primary coating to steel sheet provided with a base metal steel sheet having a predetermined chemical composition and a primary coating formed on a surface of the base metal steel sheet and containing Mg2SiO4 as a main constituent, where a peak position of Al emission intensity obtained when performing elemental analysis by glow discharge optical emission spectrometry from a surface of the primary coating in a thickness direction of the grain-oriented electrical steel sheet is arranged within a range of 2.4 to 12.0 μm from the surface of the primary coating in the thickness direction, a number density of Al oxides at the peak position of Al emission intensity and of a size of 0.2 μm or more in terms of a circle equivalent diameter based on the area is 0.03 to 0.18/μm2, and, in a plurality of Al oxides in an observed region in an observed region of 30 μm×50 μm at the peak position of Al emission intensity, a total cross-sectional area of identified Al oxides with cross-sectional areas of 0.4 to 10.0 μm2 is 75.0% or more of the total cross-sectional area of all Al oxides in the observed region.