| 摘要 |
PROBLEM TO BE SOLVED: To provide a flux-cored wire for gas shield arc welding of a high-tensile steel excellent in welding workability by which a weld metal having adequate strength and favorable stable toughness in a low-temperature region is obtained.SOLUTION: A flux-cored wire for gas shield arc welding of a high-tensile steel contains: in mass% based on total wire mass and in total of steel outer coat and flux, 0.08-0.16% C, 0.3-0.75% Si, 1.2-2.1% Mn, 0.15-0.45% Cu, 0.8-3.0% Ni, 0.35-0.65% Cr, 0.2-0.6% Mo and 0.04-0.30% Ti. Further, the flux contains 0.01-0.1% F compounds in total of F conversion value, 0.01-0.2% SiO, and 0.02-0.15% Na and K compounds in total of NaO and KO conversion values, and Pts represented by the following expression (1): Pts=[C]+[Si]/7+[Mn]/5+[Cu]/7+[Ni]/20+[Cr]/8+[Mo]/2+[Ti]/5 is controlled to be 0.8 to 1.2.SELECTED DRAWING: None |
