The present study analyses combined effect of magnetic fields obtained by two types of magnetic configurations (NSN and SNS) on weld bead characteristics and microhardness in GTAW. For this analysis, a newly designed three-poles (E-type) electromagnet was installed to generate a combination of two symmetrically transverse external magnetic fields. Material selected for the experiment is high strength low alloy (HSLA); S355J2+N grade with 10 mm thickness. It was observed from the results that the symmetrically transverse magnetic fields are capable to enhance the weld bead appearance, weld width, shape, and microhardness. It was also observed that for different values of excitation current, magnetic fields generated with both configurations viz., NSN and SNS provide overall greater bead width, and higher penetration shape factor in comparison to specimens welded with conventional GTA welding. The configurations NSN and SNS of the E-type magnet provide improvement in penetration shape factor by 61.5% and 58%, respectively. These configurations are found to be more suitable for the purpose of weld cladding and hard facing. Whereas the microhardness can be improved by 6.7% and 8.2% under the magnetic configurations NSN and SNS, respectively.

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