| 摘要 |
[Object] There is provided a flux-cored wire capable of obtaining a weld metal having excellent low temperature toughness and improving welding efficiency, in which preheating performed for preventing cold cracking can be omitted or simplified.;[Means for Solving Problems] The flux-cored wire includes one or more of CaF2, BaF2, SrF2, MgF2, and LiF and, when a total amount thereof is defined as a, the α is 2.0% to 7.0%, by mass %, with respect to a total mass of the flux-cored wire, one or more of a Ti oxide, a Si oxide, a Mg oxide, an Al oxide, a Zr oxide, and a Ca oxide are included in the flux-cored wire, and when a total amount thereof is defined as β, the β is 0.2% to 0.9%, by mass %, with respect to the total mass of the flux-cored wire, a ratio of an amount of the CaF2 with respect to the α is 0.90 or more, and a ratio of the α with respect to the β is 3.0 or more and 15.0 or less. |
| 主权项 |
1. A flux-cored wire for gas-shielded arc welding comprising:
an outer steel sheath; and a flux with which the outer steel sheath is filled, wherein one or more of CaF2, BaF2, SrF2, MgF2, and LiF, which are metal fluorides, are included in the flux-cored wire and, when a total amount thereof is defined as α, the α is 2.0% to 7.0%, by mass %, with respect to a total mass of the flux-cored wire, one or more of a Ti oxide, a Si oxide, a Mg oxide, an Al oxide, a Zr oxide, and a Ca oxide, which are metal oxides, are included in the flux-cored wire and, when a total amount thereof is defined as β, the β is 0.2% to 0.9%, by mass %, with respect to the total mass of the flux-cored wire, one or more of CaCO3, BaCO3, SrCO3, MgCO3, and Li2CO3, which are metal carbonates, are included in the flux-cored wire and a total amount thereof is less than 0.6%, by mass %, with respect to the total mass of the flux-cored wire, a ratio of an amount of the CaF2 with respect to the α is 0.90 or more, a ratio of the α with respect to the β is 3.0 or more and 15.0 or less, an amount of the Ti oxide is 0% to 0.4%, by mass %, with respect to the total mass of the flux-cored wire, an amount of the Si oxide is 0.2% to 0.5%, by mass %, with respect to the total mass of the flux-cored wire, an amount of the Ca oxide is less than 0.20%, by mass %, with respect to the total mass of the flux-cored wire, an amount of an arc stabilizer in the flux is 0% to 0.50%, by mass %, with respect to the total mass of the flux-cored wire, an amount of an iron powder in the flux is less than 5%, by mass %, with respect to the total mass of the flux-cored wire, chemical compositions except the metal fluorides, the metal oxides, and the metal carbonates include, by mass %, with respect to the total mass of the flux-cored wire, C: 0.003% to 0.040%; Si: 0.05% to 0.40%; Mn: 0.2% to 0.8%; Al: 0.003% to 0.050%; Ni: 6.0% to 16.0%; P: 0.02% or less; S: 0.01% or less; Cu: 0% to 0.5%; Cr: 0% to 0.5%; Mo: 0% to 0.5%; V: 0% to 0.2%; Ti: 0% to 0.1%; Nb: 0% to 0.1%; B: 0% to 0.01%; Mg: 0% to 0.6%; REM: 0 to 0.0500%; and a remainder: Fe and an impurity, a SM defined by the below expression a is 0.3% to 1.0%, a Ceq defined by the below expression b is 0.250% to 0.525%,
SM=[Si]+[Mn]: (Expression a),Ceq=[C]+( 1/24)[Si]+(⅙)[Mn]+( 1/40)[Ni]+(⅕)[Cr]+(¼)[Mo]+( 1/14)[V]: (Expression b), and in the Expressions a and b, elements noted in brackets express amounts (mass %) of the elements, respectively. |
