Recycled Slag Consumption in Submerged Arc Welding and Its Effect on Microstructure of Weld Metal

Slag generated during conventional submerged arc weld was collected and processed by replenishing it with suitable alloying elements/deoxidizers by agglomeration. This replenished slag is referred to as recycled slag. Recycled slag in combination with EL-8 filler wire was used in these investigations. The effect of welding parameters on flux (recycled slag) consumption has been investigated. Mathematical model has been developed from the data generated using two level factorial technique. The significance of coefficients and adequacy of developed model have been checked by Students ‘t’ test and F test respectively. The main effects of welding parameters on recycled slag consumption have been presented in graphical form for better understanding. The developed model is useful for controlling and predicting slag consumption in submerged arc welding. The physical behavior of recycled slag during welding was also observed. Microstructure of weld metal was analyzed.