High strength weld joint with excellent cryogenic impact toughness and flux cored arc welding wire for this purpose

摘要

A high-strength weld joint having excellent cryogenic impact toughness and a flux cored arc welding wire therefor are provided. The present invention relates to a welded joint part obtained by welding high strength high Mn steel for cryogenic use, wherein the welded joint part is C: 0.1 to 0.61% by weight, Si: 0.23 to 1.0%, Mn: 14 to 35%, Cr: 6% or less, Mo: 1.45 to 3.5%, S: 0.02% or less, P: 0.02% or less, B : 0.001 to 0.01%, Ti: 0.001 to 0.2%, N: 0.001 to 0.3%, high strength welding excellent in cryogenic toughness including the remainder Fe and other inevitable impurities Joint part and by weight C: 0.15-0.8%, Si: 0.2-1.2%, Mn: 15-34%, Cr: 6% or less, Mo: 1.5-4% , S: 0.02% or less, P: 0.02% or less, B: 0.01% or less, Ti: 0.1-0.5%, N: 0.001-0.3%, TiO2: 4 ~ 15%, SiO One or more of ZrO2 and Al2O3: 0.01 to 9%, One or more of alkaline elements such as K, Na and Li: 0.5 to 1.7%, One or more of F and Ca : It relates to a wire for flux cored arc welding containing 0.2 to 1.5%, balance Fe and other inevitable impurities. [Selection figure] None