PRODUCTION OF GRAIN-ORIENTED SILICON STEEL SHEET HAVING HIGH MAGNETIC FLUX DENSITY

• Main Authors: NOZAWA TADAO, SUGA YOUZOU, NAKAYAMA TADASHI
• Format: Patent
• Language: English
• Published: 05.12.1984
• Edition: 3
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INDUCTANCES; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MAGNETS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TRANSFORMERS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PURPOSE:To produce a grain-oriented silicon steel sheet having a high magnetic flux density by specifying the content of N in the steel sheet at the start of secondary recrystallization in the stage of subjecting the silicon steel material contg. C, Si and solAl at specific ratios to secondary recrystallization annealing. CONSTITUTION:A silicon steel material consisting of 0.010-0.10% C, 2.5-4.0% Si, 0.010-0.065% solAl, and the balance Fe with inevitable impurities is subjected to secondary recrystallization annealing while a temp. gradient is given to the boundary region of the primary recrystallization region and secondary recrystallization region of final annealing in the stage of subjecting such steel material to hot rolling, cold rolling, decarburization annealing and final annealing. The content of nitrogen in the steel sheet at the start of the secondary recrystallization in the stage of such secondary recrystallization is adjusted to 130-200ppm and the steel sheet is annealed in an atmosphere contg. >=25% nitrogen and the balance hydrogen. The magnetic flux density B8 at 800AT/m magnetizing force is thus stabilized at about >=1.96T.