Metallic flux cored wire, welding process with the same, and process for production of welded joints having high fatigue strength with little slag

摘要

The invention provides a metallic flux cored wire which is suppressed in the formation of slag and can secure good coatability; a gas-shielded arc welding process with the wire; and a process for the production of welded joints having high fatigue strength with little slag. A wire for gas-shielded arc welding comprising a steel sheath and a metallic flux packed in the steel sheath, which contains, by mass based on the whole wire, C: 0.001 to 0.20% exclusive of graphite and SiC, graphite: 0.10 to 0.7%, Si: 0.05 to 1.2% exclusive of SiC and Si02, Mn: 0.2 to 3.0%, P: 0.03% or below, S: 0.02% or below, and one or more of SiO2, Al2O3, Na2O, and K2O: 0.05 to 0.40% in total, the balance being iron and unavoidable impurities, with the proviso that graphite and one or more of SiO2, Al2O3, Na2O, and K2O are contained at least as the flux.