FLUX FOR SUBMERGED ARC WELDING

摘要

Provided is a flux for submerged arc welding that has good welding workability and can reduce the diffusion hydrogen content in a weld metal in the use of either an AC or a DC welding power source. The flux for submerged arc welding includes: MgO: 25 to 35% by mass; F (in terms of CaF2): 15 to 30% by mass; Al2O3: 10 to 25% by mass; SiO2: 10 to 20% by mass; at least one of Na (in terms of Na2O) and K (in terms of K2O): 0.5 to 5.5% by mass in total; Fe (in terms of FeO): 0.5 to 5% by mass; TiO2: 1 to 5% by mass; CaO: 6% by mass or less; and Mn (in terms of MnO): less than 2.0% by mass; and further includes: water-soluble SiO2: less than 1% by mass; wherein the flux satisfies the following numerical expression (I):;0.5≦[MgO][Al2O3]+[CaF2]+[TiO2]≦1.1(I)

主权项

1. A flux for submerged arc welding, comprising:
MgO: 25 to 35% by mass; F (in terms of CaF2): 15 to 30% by mass; Al2O3: 10 to 25% by mass; SiO2: 10 to 20% by mass; at least one of Na (in terms of Na2O) and K (in terms of K2O): 0.5 to 5.5% by mass in total; Fe (in terms of FeO): 0.5 to 5% by mass; TiO2: 1 to 5% by mass; CaO: 6% by mass or less; and Mn (in terms of MnO): less than 2.0% by mass; and further comprising: water-soluble SiO2: less than 1% by mass; wherein the flux satisfies the following numerical expression (I):0.5≦[MgO][Al2O3]+[CaF2]+[TiO2]≦1.1(I)where [MgO] is an MgO content, [Al2O3] is an Al2O3 content, [CaF2] is an F content (in terms of CaF2), and [TiO2] is a TiO2 content.