Regulation effect of external electric field inducing oxygen flow on molten slag oxidation in submerged arc welding

During submerged arc welding, the direct current external electric field between molten slag and liquid metal was applied behind the arc to induce directional migration for free oxygen ion, so as to regulate electrochemical oxidation behavior with no change basicity index of molten slag. The variation of oxygen content in weld pool is caused by electrochemical reactions, which occurs at interface of slag-metal for external electric field was studied quantitatively based on Faraday law of electrolysis. Theoretical calculation and experimental test show that the oxygen content of weld metal can be regulated in certain degree with the change of current between slag and metal by external electric field change or regulating technological factors such as weld speed, fusion ration, and it may also influence the metallurgy behavior of active alloying elements in weld metal as well as the formation of inclusion.