| 摘要 |
PROBLEM TO BE SOLVED: To provide a high carbon steel sheet excellent in local ductlity such as stretch-flanging properties or the like. SOLUTION: This steel sheet is the one composed of high carbon steel of, by mass, 0.7 to 1.5% or >0.8 to 1.5% C and <=0.01% S, in which carbides are dispersed into ferrite in such a manner that the average carbide grain size is controlled to 0.4 to 1.2μm, the notch tensile elongation Elv is >=30%, and also, the hole expanding ratioλis >=30%. The one in which, as steel components, Si, Mn, Cr, Mo, Cu, Ni or the like is added by suitable quantity can be used.
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