MANUFACTURE OF HOT ROLLED ORIGINAL SHEET FOR CONTINUOUSLY ANNEALED COLD ROLLED STEEL SHEET OR CONTINUOUSLY GALVANIZED COLD ROLLED STEEL SHEET AT HIGH YIELD

• Main Authors: UEDA TOSHIZUMI, ITO NOBUAKI, MATSUZU NOBUHIKO, KOYAMA KAZUO
• Format: Patent
• Language: English
• Published: 23.02.1993
• Subjects: ALLOYS; 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; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PURPOSE:To offer a manufacturing method of a hot rolled original sheet for a continuously annealed cold rolled steel sheet or a continuously galvanized cold rolled steel sheet used for automobile parts or the like at a high yield. CONSTITUTION:At the time of subjecting a steel contg. 0.01 to 0.025% C, 0.05 to 0.2% Mn, <=0.015% P, 0.004 to 0.015% S, 0.05 to 0.15% Al and <=0.0025% N to hot rolling and coiling it at 640 to 700 deg.C, the coiling temp. in the part with each >=3% length of both edge parts of the coil is regulated to 680 to 850 deg.C to prevent loosening, and the cooling rate at the edge parts is regulated to <=3 deg.C/min from the temp. of >=550 deg.C. Furthermore, immediately after the start of the coiling, it is possible to expand a mandrel and to seam the inner circumferential part tight.