Abstract: A steel pipe is provided which is excellent in resistance to outer surface stress corrosion cracking (SCC) when used for a pipeline without impairing the fundamental requirement for the steel as a pipeline. The steel pipe has a surface adjusted to have a mean line roughness Ra of up to 7 &mgr;m and a maximum height Rmax of up to 50 &mgr;m. The surface is adjusted by sand blasting to have this roughness.

Abstract: Steel is obtained which comprises by wt %, C: 0.001-0.025%, Si: not more than 0.60%, Mn: 0.10-3.00%, P: 0.005-0.030%, S: not more than 0.01%, Al: not more than 0.10%, Cu: 0.1-1.5%, Ni: 0.1-6.0%, B: 0.0001-0.0050%, and the balance being Fe and inevitable impurities; since the steel contains C and P in small contents, stable amorphous rusts are formed on the surface thereof at an early stage; and steel simultaneously realizes excellent weather resistance, material weldability and toughness particularly in an environment such as a seashore district and the like where salt is present in a large amount.