Unveiling Droplet Zone Element Transfer Behaviors of CaO–SiO2–MnO Fluxes in the EH36 Shipbuilding Steel Subject to Submerged Arc Welding

Quantifying the degree of element transfer within the droplet zone during submerged arc welding (SAW) remains challenging due to the coverage of the droplet zone by fluxes and the presence of arc plasma, which are characterized by exceedingly high temperatures and short lifetime. This present study has investigated element transfer behaviors within the droplet zone during SAW by employing fused CaO–SiO₂–MnO fluxes with varying MnO contents and welding current intensities. An apparatus designed for capturing droplets in SAW was employed. The results indicate that, as the welding current increases from 200 to 400 A, the average transfer levels of Si, Mn, and O in the fluxes to the droplet increase by 1.81, 2.52, and 1.42 times, respectively. As the MnO content increases from 10 to 60 wt pct, the average transfer levels of Si, Mn, and O in the fluxes to the droplet increase by 24.97, 3.01, and 2.22 times, respectively. Our current findings may facilitate elucidating the influence of arc plasma on element transfer within the droplet zone, thereby establishing a theoretical framework for comprehensively understanding the contribution of individual reaction zones during SAW.