COLD ROLLED STEEL PLATE HAVING EXCELLENT BAKING HARDENABILITY NON-COLD AGEING CHARACTERISTICES AND MOLDABILITY, AND MOLTEN ZINC-PLATED COLD-ROLLED STEEL PLATE AND METHOD OF MANUFACTURING THE SAME

• Main Authors: YOSHINAGA, NAOKI, AKISUE, OSAMU, NISHIMURA, KUNIO, USHIODA, KOHSAKU
• Format: Patent
• Language: English; Korean
• Published: 06.02.1997
• Edition: 6
• 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

A cold rolled steel plate having excellent baking hardenability, non-cold-ageing characteristics and moldability, and a molten zinc-plated cold-rolled steel plate and a method of manufacturing the same. The structure of an annealed product is turned into mixed structure by positively adding Mn and Cr to a base material of very low carbon steel or very low carbon steel containing not less than one of Ti and Nb. This enables a steel plate having both a high paint-baking hardenability and a high non-cold-ageing characteristics as well as a high processability represented by an average r-value (deep drawing characteristics) to be obtained. Especially, the paint-baking hardenability is such that a cold-rolled steel plate and a molten zinc-plated cold-rolled steel plate which provide a BH amount as high as around 10 kgf/mm as necessary, and which also have excellent non-cold-ageing characteristics, can be provided.