For SMAW, which current type will eliminate arc blow in many cases?

• A. Alternating current (AC)
• B. Direct current (DC)
• C. Pulsed current
• D. Constant current (CC)

Answer: (A)

Arc blow is the sideways wandering of the welding arc caused by the magnetic field created by the welding current and the workpiece. Alternating current reverses polarity each half cycle, so the magnetic field around the arc keeps flipping direction. Those changing fields don’t build up in one direction, which cancels the net deflecting force on the arc. The arc stays closer to the joint, so arc blow is often eliminated in SMAW when using AC.

Pulsed current changes current magnitude over time but doesn’t inherently cancel the steady magnetic effects the same way AC does. Direct current provides a continuous magnetic field in one direction, which can promote arc blow, and constant current is a control mode, not a different current type.