| 摘要 |
<p>Submerged arc welding for nickel containing steel such as steel containing 3.5 weight percent of nickel. The process uses a bond type of flux of specific composition to suppress the oxygen content in the weld metal. Further, the process utilizes a cored welding wire including a core material of specific composition. As the result, it is possible to obtain a weld metal of high impact-resistance at low temperature such as minus 100.degree.C. The welding electrode is a cored wire consisting of a mild steel and core material, the core material including, on the basis of weight to the total weight of the welding electrode, 5 to 25 percent of CaF2, 2.5 to 5.5 percent of nickel, O to 0.5 percent of Mo, 0 to 0.5 percent of Ti. The flux is a bond type flux having a composition of, by weight percent, 10 to 30 percent of SiO2, 8 to 20 percent of A12O3, 25 to 45 percent of MgO, 10 to 30 percent of CaO, 7 to 20 percent of CaF2, and at least one member selected from the group consisting of metallic Si, Fe-Si, Fe-Si-Mn, the amount of Si in all cases being 6 percent or less calculated in terms of metallic Si. The flux has a basicity B higher than 1.5, the basicity being defined on the basis of weight by the following equation: .</p> |
