| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel for ships, improving a corrosion resistance (especially, a crevice-corrosion resistance). SOLUTION: This steel is composed of 0.01-0.3% C, 0.01-2% Si, 0.01-2% Mn, 0.005-0.1% Al,≤0.010% S, 0.01-5% Cu, 0.01-5% Ni, 0.01-5% Cr, 0.005-0.2% Ti, 0.0005-0.02% Ca and the balance Fe with inevitable impurities. Further, in the cross-section vertical to a rolled surface, a ferrite structure is mainly contained and also, an area ratio of a pearlite structure is≤10% to the whole structure, and in the cross-section vertical to the rolled surface and along the rolling direction, the area ratio of the pearlite structure having≥2 aspect ratio, is≥40% to the whole pearlite structure, and the difference obtained by subtracting the pearlite area ratio in the cross-section along the rolling direction vertical to the rolled surface, from the pearlite area ratio in the cross-section parallel to the rolled surface, is≤8%. COPYRIGHT: (C)2010,JPO&INPIT
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