| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas-shielded arc welding method which is suitable for straight polarity d.c. welding, and by which the occurrence burn through defects in the case of welding a thin steel sheet can be prevented, and which is excellent in gap weldability and arc stability and less in the generation of spotless so that sound welding is possible even in a joint having a wide gap. SOLUTION: A steel wire having a composition containing, by mass, <=0.20% C, 0.25 to 2.5% Si, 0.45 to 3.5% Mn, <=0.050% P and 0.05% S is used as a straight polarity. Welding is performed using a shield gas containing <=98 vol.% Ar in the ranges where welding current satisfies 50 to 300 A, welding voltage E satisfies EL<=E<=EH, and welding velocity satisfies 20 to 250 cm/min.
|
