| 摘要 |
A flux-cored wire for gas shielded arc welding is provided to obtain excellent high speed weldability and porosity resistance and improved slag covering property and slag peeling property at the same time when welding a low Si soft steel, a low Mn-based material, and a high strength steel of which surfaces are painted with an inorganic zinc primer or covered with a black layer. As a flux-cored wire for gas shielded arc welding, in which a flux is filled in a soft steel sheath, the flux-cored wire for gas shielded arc welding is characterized in that the flux comprises, when calculating according component ratio relative to wire gross weight, 0.10 to 0.30 mass% of Zr converted from a metal Zr source, 0.30 to 1.0 mass% of ZrO2, 1.0 to 5.0 mass% of TiO2, 0.30 to 1.0 mass% of SiO2, 0.10 to 0.30 mass% converted from a metal Al source, and 0.04 to 0.10 mass% in total of Na2O and K2O converted from alkali metal sources Na and K, the ratio of K2O/Na2O being 1.0 to 3.0, and at least one selected from the group consisting of Al2O3, Mg, Fe-Mn, Fe-Si, K2SiF6, and iron.
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