FLUX FOR SUBMERGED ARC WELDING TO 960MPA HIGH TENSILE STRENGTH STEEL

摘要

PURPOSE: To produce a weld zone good in welding operability and welding cracking resistance and excellent in mechanical properties by specifying the compsn. of flux and limiting the carbon equivalent. ;CONSTITUTION: This flux has a compsn. contg., by weight to the whole flux, 6 to 15% SiO₂, 6 to 15% CaO, 15 to 25% MgO, 10 to 25% Al₂O₃, 3 to 10% CaF₂, metal carbonate; 3 to 10% expressed in terms of CO₂ and Li carbonate or Li fluoride; 0.02 to 1.0% expressed in terms of Li. Moreover, it contains, to the whole body of the iron alloy, 0.01 to 0.12% C, ≤0.23%. Si, 1.0 to 2.1% Mn, 1.5 to 4.5% Ni, 0.85 to 1.60% Cr and 0.55 to 1.20% Mo, and the iron alloy in which the carbon equivalent (Ceq) shown by the formula is regulated to 0.58 to 0.70% is incorporated by 15 to 40% to the flux. Furthermore, 1 to 10% of at least one kind of MgF₂, and MnF₂ is preferably added to the flux.;COPYRIGHT: (C)1995,JPO