1977 Volume 46 Issue 3 Pages 165-171
The effect of slag basicity on silicon and manganese deoxidation in the submerged-arc welding process is considered by bead-on-plate welding performed using agglomerated fluxes of CaO-MgO-Al2O3-SiO2 system.
Dissolved oxygen content in molten pool is remarkably affected by oxygen which is originated from dissociation of silica in slag, then oxygen content in weld metal can be decreased by a reduction of the activity of silica. The arc cavity is almost filled with CO gas, and PCO2/PCO in the atmosphere is decreased with increasing slag basicity. Ratio of oxygen content in weld metal to FeO content in slag takes a constant value independently of the slag basicity. Oxygen in weld metal deposited with MnO-free fluxes seems to be quasi-equilibrium relation with silicon at about 1950°C independently of manganese content in weld metal.