STEEL SHEET FOR DEEP DRAWING HAVING EXCELLENT SECONDARY WORK EMBRITTLEMENT RESISTANCE, FATIGUE PROPERTIES AND PLATING PROPERTIES, AND METHOD FOR MANUFACTURING THE SAME

• Main Authors: CHOI, CHANG-SIK, CHIN, KWANG-KEUN, KANG, HEE-JAE, HAN, SANG-HO
• Format: Patent
• Language: English; French; German
• Published: 24.03.2010
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

A steel sheet for deep drawing used for automobiles, and a method for manufacturing the same are disclosed. The steel sheet comprises, by weight %, C: 0.010% or less, Si: 0.02% or less, Mn: 0.06~1.5%, P: 0.15% or less, S: 0.020% or less, Sol. Al: 0.10~0.40%, N: 0.010% or less, Ti: 0.003~0.010%, Nb: 0.003~0.040%, B: 0.0002~0.0020%, and the balance of Fe and other unavoidable impurities, wherein the composition of Ti, Al, B, and N satisfies the relationship: 1.0<(Ti[%]+Al[%]/16+6B[%])/3.43N[%]<4.1, and wherein the composition of Nb, Al, and C satisfies the relationship; 0.7<(Nb[%]+Al[%]/20)/7.75C[%]<3.5. The steel sheet exhibits excellent secondary work embrittlement, fatigue properties of welded joints, and an appealing plated surface as well as excellent formability.