CORROSION RESISTANT STEEL FOR CRUDE OIL TANK, MANUFACTURING METHOD THEREFOR, AND CRUDE OIL TANK

摘要

Disclosed is a corrosion resistant steel for crude oil tank, which not only has excellent resistance to general corrosion and local corrosion, but also has excellent corrosion resistance in cases the steel is used in a condition with Zn present on the steel surface. Specifically, the corrosion resistant steel for crude oil tank contains, in mass%, C: 0.001-0.16%, Si: 1.5% or less, Mn: 0.1-2.5%, P: 0.025% or less, S: 0.01% or less, Al: 0.005-0.1%, N: 0.001-0.008%, Cu: 0.008-0.35%, Cr: greater than 0.1% and 0.5% or less, and Sn: 0.005-0.3%, wherein Mo: 0.01% or less, and the value for A1, defined by the formula, is 0 or less. A1 = 28 × [C] + 2000 × [P]2 + 27000 × [S]2 + 0.0083 × (1/[Cu]) + 0.027 × (1/[Cr]) + 95 × [Mo] + 0.00098 × (1/[Sn]) - 6