MANUFACTURE OF HIGH STRENGTH STEEL PLATE HAVING GOOD WORKABILITY AND CORROSION RESISTANCE

• Main Authors: OKAMOTO ATSUKI, TARUYA YOSHIO, NAGAI NAOMITSU
• Format: Patent
• Language: English
• Published: 19.05.1989
• 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 manufacture high strength steel plate having good workability and corrosion resistance by hot-rolling the steel containing the specific ratio of C, Si, Mn, P, Cr, Al, Cu, Ni, heating to the specific temp. and continuously executing hot dip galvernizing. CONSTITUTION:The steel having composition of 0.02-0.15% C, 0.2-1.5% Si, 0.10-0.80% Mn, <=0.09% P, 1.5-3.0% Cr, <=0.08% Al, <=1.0% Cu, <=1.0% Ni and the balance Fe with inevitable impurities is produced. Successively, after hot-rolling or cold-rolling this steel, the steel is heated to 750-880 deg.C and cooled at near zinc plating temp. of about 400-500 deg.C and the hot dip galvernizing is continuously executed. Then, if necessary, further alloying treatment is executed at about 530-650 deg.C for about 10sec. By this method, the steel plate having the corrosion resistance near stainless steel and the workability and the high strength more than mild steel plate is obtd.