| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel material excellent in corrosion resistance which can be suitably used as a material for a steel structure requiring excellent corrosion resistance in air-polluted environment containing large amounts of sulfur oxides. SOLUTION: This steel material is characterized in that: it has a composition which contains, by mass, at least one element selected from among C, Si, Mn, S, Ti, Ca, Cu and Ni and Al in respectively specified percentages and has the balance Fe with inevitable impurities, wherein a relationship represented by [(Ni+4.5×Cu)×S×2500×Ti>5] is present among the respective contents of Ni, Cu, S and Ti; its surface is covered with rust containing respectively specified percentages of S and at least one element selected from among Ti, Cu, Ni, Nb, Zr and V; a rust layer in which a crystallite size ofβ-FeOOH component is <50 nm is formed on the surface; and the rust layer has a specific surface area of≥10 m<SP>2</SP>/g. COPYRIGHT: (C)2008,JPO&INPIT
|
