Effect of Surface-Active Flux on Bead Geometry in AISI 304 Stainless Steel Deposited Using Submerged Arc Welding

Submerged arc welding (SAW) is a well-established and versatile process of joining thick materials. This process has applications in ship building industry, pressure vessel fabrication, and structural welding. Weld pool geometry is very crucial in achieving good mechanical properties and defect free welds. The selection of welding parameters affects the weld pool geometry. This study examines the effect of surface-active elements on weld bead geometry in bead-on-plate welding. The application of surface-active fluxes modifies weld pool behavior, leading to potential reductions in welding time and improvements in productivity. Four oxide fluxes—SiO2, TiO2, Cr2O3, and a ternary mixture—were selected for evaluation. Comparative analysis was performed between welds produced with and without flux to assess changes in weld geometry. The primary output parameters investigated were weld width, penetration depth, and reinforcement height. The results revealed that using a mixture of all three fluxes led to a 95% increase in penetration compared to welds without flux. The use of Cr2O3 alone increased penetration by up to 60%, while TiO2 increased bead width by approximately 10% relative to the baseline. Furthermore, reinforcement height was enhanced by up to 30% when Cr2O3 was used. These enhancements demonstrate that surface-active fluxes not only improve weld geometry but also enable deeper, narrower welds with potentially reduced heat input, improving efficiency and weld quality.