ELECTROMAGNETIC STEEL SHEET HAVING INSULATING COATING

摘要

An insulating coating for application to an electromagnetic steel sheet, comprised mainly of a Zr compound, an Al compound and a Si compound, optionally further phosphoric acid and/or a phosphate salt, wherein the total content of Zr compound (in terms of ZrO2) and phosphoric acid or the like (in terms of PO4) is regulated so as to range from 45 to 90 mass% on a reduced basis per the total mass of solid contents of the insulating coating. The thus obtained insulating coating despite one whose main components are inorganic substances not containing chromium excels in, after baking at <=300°C but before strain-removing annealing, corrosion resistance, anti-powdering property and appearance and excels in, after strain-removing annealing, scratch resistance. Further application of an upper layer coating containing a resin, etc. is also preferable.