| 摘要 |
PURPOSE: A titania type flux cored wire with an excellent crack resistance is provided to effectively prevent a hot cracking of a welding unit in a first layer welding of a rear plate, and to have an excellent impact toughness. CONSTITUTION: A titania type flux cored wire with an excellent crack resistance comprises as a weight% about all weight of a wire, C: 0.035-0.050%, Ti2O: 5.5-8.5%, MgO: 0.2-0. 7, SiO2: 0.3-0.8, Na2O: 0.1-0.7, K2O: 0.1-0.3%, Si: 0.4-0.6%, Mn: 1.5-2.5%, Mg: 0.3-0.7%, F computed quantity of a fluoride: 0.05-0.15%, and a rest comprises Fe among an outer cover, iron, and an unavoidable impurity. A value of (Mn/Si)×C is 0.15-0.20. A titania type flux cored wire obtains a weld metal with an excellent impact toughness, and enlarges a yield ratio (a ratio of a maximum tensile strength / a lower yield strength) of a weld metal. |
