| 摘要 |
PROBLEM TO BE SOLVED: To provide a flux-cored wire for carbon dioxide gas shielded welding which is excellent in strength and toughness of welded metal even in welding construction conditions of large heat input and high interpass temperature and has superior welding operability.SOLUTION: In a flux-cored wire, one side or both sides of steel skin and flux contain, with respect to wire total mass, 0.08 to 0.15% of C, 0.5 to 1.5% of Si, 1 to 2.5% of Mn, 0.1 to 0.5% of Cu, 0.1 to 0.35% of Mo, 0.1 to 0.35% of Ti, 0.002 to 0.01% of B and flux contains, with respect to wire total mass, 0.05 to 0.2% of the total of a NaO conversion value of an Na compound and a KO conversion value of a K compound, 0.1 to 1% of the total of a SiOconversion value of an Si oxide and further, as necessary, contains 0.04 to 0.08% of Mg, 0.1 to 0.5% of the total of an Al conversion value and 0.01 to 0.2% of the total of a F conversion value. |
