| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel sheet in which the generation of initial period rust is sufficiently delayed even under chlorine ion environment at a low cost and its manufacturing method. SOLUTION: The steel sheet is characterized by having a chemical composition containing, by mass%, 2.1 to 3.5% Si, 0.4% or less Mn, 0.5 to 5.0% Al, and satisfying [Si]/[Mn]≥6, and having an oxide film of≥10% in a maximum Al mass ratio on the surface where [M] denotes a content (mass%) of an element (M); the maximum Al mass ratio is a maximum value in the thickness direction of the mass ratio of Al with respect to the total amount of Fe, Si and Al in the oxide film obtained by the glow discharge spectrochemical analysis (GDS). COPYRIGHT: (C)2010,JPO&INPIT |
