Steel with superior anisotropy for impact toughness and the method of producing the same

摘要

PURPOSE: Steel with superior anisotropy for impact toughness and a method of producing the same are provided to achieve the superior anisotropy for impact toughness by controlling the shape of MnS without addition of expensive rare earth materials. CONSTITUTION: Steel comprises C 0.06~0.10 weight%, Si 0.15~0.35 weight%, Mn 1.00~1.50 weight%, P 0~0.025 weight% or less, S 0~0.025 weight%, Nb 0.02~0.05 weight%, Zr 0.01~0.20 weight%, Al 0.02~0.05 weight%, Ca 0.001~0.005 weight%, N 0.006~0.012 weight%, V 0.02~0.004 weight%, Ni 0.1~0.7weight%, Ti 0.01~0.03 weight%, and Fe and inevitable impurities of the rest amount. The impact toughness anisotropy of the steel is 55% or greater.