WELDING JOINT EXELLENT IN TOUGHNESS AND CONTROL OF FATIGUE CRACK INITIATION PROPERTY

摘要

Welding joint is provided to suppress fatigue crack due to micro-crack in the boundary of steel sheet and welding metal and to improve HAZ(Heat Affected Zone) toughness. In welding joint with superior toughness and fatigue crack prevention characteristic, a steel sheet contains C(Carbon) of 0.01~0.06wt.%, Si(Silicon) of 0.01~0.5wt.%, Mn(Manganese) of 0.5~2.0wt.%, Al(Aluminum) of 0.005~0.10wt.%, Nb(Niobium) of 0.005~0.05wt.%, Ti(Titanium) of 0.008~0.03wt.%, B(Boron) of 0.001~0.005wt.%, N(Nitrogen) of 0.003~0.008wt.%, and one selected from a group. The group consists of Cr(Chromium) of 0.3~1.0wt.%, Cu(Copper) of 0.1~1.0wt.%, Ni(Nickel) of 0.1~1.0wt.%, Mo(Molybdenum) of 0.03~0.5wt.%, and V(Vanadium) of 0.02~0.05wt.%.