| 摘要 |
PROBLEM TO BE SOLVED: To provide a corrosion resistant steel material for a vessel ballast tank, which is economical and excellent in coating film blistering resistance, exhibits excellent coating film corrosion resistance under a severe sea water corrosive environment such as of a vessel ballast tank, particularly, under an environment of a combination of a sea water immersion environment and a dry-wet repeating environment where FeOtends to be generated, therefore can prolong the time until repair coating, and can lead to reduction of an operation for the repair coating.SOLUTION: A steel material for a vessel ballast tank has a component composition including, by mass, 0.03-0.20% C, 0.05-0.50% Si, 0.7-2.00% Mn, ≤0.035% P, ≤0.010% S, ≤0.100% Al, 0.005-0.030% Ti, 0.0010-0.010% N, 0.02-0.20% Sn, and <0.10% Cr, and further including one or more elements selected from 0.02-0.20% Sb, 0.005-0.50% W, 0.01-0.50% Mo, and 0.003-0.030% Nb, (0.002-0.020% of solid solubilized Nb), and the balance of Fe and inevitable impurities. |
