GRAIN ORIENTED ELECTRICAL STEEL SHEET GRAIN ORIENTED ELECTRICAL STEEL SHEET PRODUCTION METHOD GRAIN ORIENTED ELECTRICAL STEEL SHEET EVALUATION METHOD AND IRON CORE

摘要

A grain oriented electrical steel sheet having a forsterite coating on a steel sheet the grain oriented electrical steel sheet being characterized in that the proportion of the total area of defect sections scattered over the forsterite coating when viewed from the surface is less than 1.5% of the surface area of the forsterite layer. In the present invention at least some of the defect sections are preferably in the form of streaks. A grain oriented electrical steel sheet evaluation method for evaluating the adhesion between a forsterite coating and a steel sheet surface of a grain oriented electrical steel sheet having a forsterite coating on a steel sheet the grain oriented electrical steel sheet evaluation method characterized by irradiating the surface of the grain oriented electrical steel sheet with an electron beam splitting the generated light into a spectrum and evaluating the adhesion between the forsterite coating and the steel sheet surface using at least one of the intensity of an emission peak A and/or an emission peak B appearing at a wavelength of 380 600 nm and the intensity ratio thereof.