In conventional submerged arc welding (SAW) process, less than 40% of the arc energy is utilized in the melting of the electrode wire (Ref. 1). The remainder is dissipated in melting the base plate and flux, in superheating the weld pool, and lost into the plate and atmosphere. While melting of flux and base plate is essential to a certain extent, the arc energy expanded in superheating the weld pool and excessive fusion of the base plate is harmful and undesirable. The excessive melting of plate may result in deeper penetration and higher dilution. Due to this characteristic, the use of SAW is limited to the welding of thick plates only. Thus, there is a need and an opportunity for better utilization of the arc energy. To achieve this, a variation of SAW can be utilized in which the ferro alloy powders of desired composition are added into the weld pool ahead of the arc (Refs. 2-13).
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