Which welding technique is most likely to be affected by magnetic fields leading to arc blow?

The correct answer pertains to Shielded Metal Arc Welding (SMAW). This technique is particularly susceptible to arc blow due to the nature of the welding process. In SMAW, the electric arc is generated between the electrode and the workpiece, and when a magnetic field is present, it can influence the path of the arc.

As the arc is deflected by the magnetic field, it can cause instability and difficulties in maintaining a uniform bead appearance, leading to defects in the weld. This phenomenon is especially noticeable when working on thicker materials or in situations where direct current (DC) polarity is used, further enhancing the effects of magnetic fields.

Other welding techniques, such as TIG welding, submerged arc welding, and gas metal arc welding, may experience some degree of arc instability, but the impact of magnetic fields on those processes is generally less pronounced compared to SMAW. For instance, TIG welding utilizes a non-consumable tungsten electrode, which tends to be less affected by the magnetic fields due to its different current characteristics. Submerged arc welding employs a granular flux, which shields the arc, mitigating some external influences, and gas metal arc welding uses a continuously fed wire which can offer a more stable arc under magnetic interference.

In sum, the unique