Production method of ultra-high magnetic flux density grain-oriented electrical steel sheet having excellent film properties and high magnetic field iron loss

摘要

PROBLEM TO BE SOLVED: To provide a ultara-high magnetic flux density grain-oriented silicon steel sheet having high magnetic field iron loss and excellent film characteristics and a method of manufacturing the same.;SOLUTION: The grain-oriented silicon steel sheet is characterized in that Bi exists at ≥0.01 to ≤1,000 ppm by weight at the boundary between base iron and a primary film. Such grain-oriented silicon steel sheet can be obtained by heating the steel sheet to a temperature region of ≥700°C at a heating rate of ≥100°C/s prior to decarburization annealing, then regulating the stangnaition time at ≥700°C to 1 to 20 second and controlling the atmosphere of this temperature region. The resultant grain-oriented silicon steel sheet is high in the magnetic field iron loss and excellent in the film adhesion.;COPYRIGHT: (C)2003,JPO