Thermodynamic Evaluation of Element Transfer Behaviors for Fused CaO-SiO2-MnO Fluxes Subjected to High Heat Input Submerged Arc Welding

Submerged arc welding has been performed by employing fused CaO-SiO2-MnO fluxes of varying MnO and CaO contents on EH36 shipbuilding steel grade. Transfer levels of O, Si, and Mn between fluxes and weld metals have been quantified and evaluated from thermodynamic perspectives. The results show that both slag-metal and gas-slag-metal equilibrium considerations are capable of placing limits on the direction and amount of element transferred between fluxes and weld metals.