Which polarity is used for GMAW?

Which polarity is used for GMAW?

• A. Direct current electrode positive
• B. Direct current electrode negative
• C. Alternating current
• D. Direct current electrode neutral

Answer: (A)

In GMAW, polarity governs where most of the arc heat goes and how the filler metal melts into the weld pool. The standard setup is direct current with the electrode positive, known as reverse polarity. This arrangement concentrates more heat into the workpiece, promoting deeper penetration and a stable transfer of molten filler metal for a wide range of metals and thicknesses. While other polarities exist for special cases—direct current electrode negative can be used for some transfer modes and alternating current is used for certain aluminum applications—the typical and most common choice for MIG welding is electrode positive.

In GMAW, polarity governs where most of the arc heat goes and how the filler metal melts into the weld pool. The standard setup is direct current with the electrode positive, known as reverse polarity. This arrangement concentrates more heat into the workpiece, promoting deeper penetration and a stable transfer of molten filler metal for a wide range of metals and thicknesses. While other polarities exist for special cases—direct current electrode negative can be used for some transfer modes and alternating current is used for certain aluminum applications—the typical and most common choice for MIG welding is electrode positive.