Abstract: Disclosed is a bonded flux and a solid wire for submerged arc welding, and a method for submerged arc welding of a low-temperature steel each of which gives a weld bead (weld metal) having excellent low-temperature fracture toughness with satisfactory weldability. The bonded flux includes 23-43% of MgO, 11-31% of Al2O3, 6-16% of CaF2, 7-20% of SiO2, 1.0-8.0% as CO2 equivalent of a metal carbonate, a total of 2-16% of CaO and/or BaO, 0.4-1.5% of metallic silicon, a total of 1.0-7.0% as titanium equivalent of metallic titanium and titanium oxide, a total of 0.01-0.20% as boron equivalent of metallic boron and/or boron oxide, and a total of 1.0-6.0% as equivalents of respective elements of at least one oxide of Na, K, and Li, and has a ratio ([Total Ti]+[Total B])/[SiO2] of from 0.05 to 0.55.

Abstract: It is an object of the present invention to provide a similar composition metal type welding solid wire capable of forming a welded joint having excellent cryogenic characteristics, such as ensuring a low-temperature toughness equivalent to that of the cryogenic base metal, and in addition, further having a high crack initiation resistance, and a weld metal thereof. The welding solid wire of the present invention is an iron base welding solid wire including carbon: 0.10 mass % or less (not inclusive of 0%), silicon: 0.15 mass % or less (not inclusive of 0%), nickel: 8.0 to 15.0 mass %, manganese: 0.10 to 0.80 mass %, and Al: 0.1 mass % or less (not inclusive of 0%), and oxygen in an amount of 150 ppm or less (inclusive of 0), characterized by including: a REM: 0.005 to 0.040 mass %, or chromium: 4.0 mass % or less (not inclusive of 0%).

Abstract: It is an object of the present invention to provide a similar composition metal type welding solid wire capable of forming a welded joint having excellent cryogenic characteristics, such as ensuring a low-temperature toughness equivalent to that of the cryogenic base metal, and in addition, further having a high crack initiation resistance, and a weld metal thereof. The welding solid wire of the present invention is an iron base welding solid wire including carbon: 0.10 mass % or less (not inclusive of 0%), silicon: 0.15 mass % or less (not inclusive of 0%), nickel: 8.0 to 15.0 mass %, manganese: 0.10 to 0.80 mass %, and Al: 0.1 mass % or less (not inclusive of 0%), and oxygen in an amount of 150 ppm or less (inclusive of 0), characterized by including: a REM: 0.005 to 0.040 mass %, or chromium: 4.0 mass % or less (not inclusive of 0%).