Probing the Influence of Waveforms on the Submerged Arc Weld Characteristics and Residual Stress Distribution

High deposition rates and penetrations in submerged arc welding (SAW) are possible with the direct current power source. An alternating current (AC) power source can achieve optimum weld penetration and deposition. Balance affects positive polarity duration, and offset relates to positive polarity current magnitude in AC waveform. Balance and offset impact wire feed speed (WFS), flux consumption, residual stress, weld bead profile, and hardness. This paper thoroughly investigates the effect of balance and offset on bead-on-plate low-carbon steel SAW welds. Conditions include a constant 50% balance with varying − 25%, 0%, and + 25% offset and constant 0% offset with varying 25%, 50%, and 75% balance. An X-ray diffractometer quantifies surface residual stresses. Results revealed that the negative polarity current magnitude or duration enhances the WFS due to a reduction in arc length and reduces the flux consumption due to narrow weld width. A constant 50% balance with − 25% offset resulted in enhanced residual stresses due to a higher deposition rate. Similarly, 0% offset with 75% balance caused higher stresses from significant shrinkage forces. Offset has the greatest impact on weld bead penetration, although weld bead width and reinforcement heights are sensitive to balance. Increasing balance or offset shows reduced weld hardness.