| 摘要 |
PURPOSE: A high strength ship-building steel material with excellent general and local corrosion resistances at low pH chloride solution and excellent HAZ toughness and a manufacturing method thereof are provided to prevent the organization of HAZ(Heat-Affected Zone) from being coarsened during welding by adding Ti, Nb, and V to a steel material and controlling the relation with nitrogen. CONSTITUTION: A high strength ship-building steel material comprises one or more elements selected from the group consisting of C 0.02~0.2 weight%, Si 0.05~1.5 weight%, Mn 0.2~2.0 weight%, P 0.015 weight% or less, S 0.003 weight% or less, Cu 0.05~1.0 weight%, Al 0.001~0.1 weight%, N 0.003~0.015 weight%, Ti 0.005~0.05 weight%, Nb 0.005~0.1 weight%, Ni 0.05~3.0 weight%, Cr 0.02~1.0 weight%, Mo 0.02~0.5 weight%, W 0.02~0.5 weight%, and Ca 0.0005~0.01 weight%, and the rest Fe and an inevitable impurity. |
