PRODUCTION OF GRAIN ORIENTED SILICON STEEL SHEET HAVING GOOD MAGNETIC CHARACTERISTIC

摘要

PURPOSE:To smooth the surface of a steel sheet and to produce a grain oriented silicon steel sheet having good magnetic characteristics by subjecting the surface of the grain oriented silicon steel sheet subjected to finish annealing successively to mechanical polishing by an elastic polishing material and electrolytic treatment by a water soluble chloride soln. CONSTITUTION:The surface of the grain oriented silicon steel sheet subjected to the finish annealing is mechanically polished by using the elastic polishing material which does not deteriorate the magnetic characteristics. The base material which holds the abrasive grains of the elastic polishing material consists of an elastic stock having about <=10<4>kg/cm<2> compressive Young's modulus and the grain size thereof is preferably about >=#100 grain size. The perpendicular pressure to be exerted on the surface of the steel sheet is confined to about <=3kg/cm<2>. The steel sheet is subjected to the electrolytic treatment (about 1,000A/dm<2>) by the water soluble chloride soln. (NaCl soln.) after polishing by about >=0.5mu per face by the mechanical polishing. A tensile film is further coated on the surface at need. The grain oriented silicon steel sheet which is greatly improved in the iron loss is thus produced at the low cost.