What bead characteristics are associated with very high travel speeds in FCAW?

What bead characteristics are associated with very high travel speeds in FCAW?

• A. Narrow convex bead with uneven edges
• B. Deep penetration
• C. Thick flat bead
• D. No bead formation

Answer: (A)

High travel speeds in FCAW cut heat input per unit length, so the molten pool stays narrow and cools quickly. With less heat to drive broad fusion, the bead forms as a narrow, often convex shape, and the edges don’t wet evenly, giving an uneven edge profile. Deep penetration requires more heat input and thus slower speeds, a thick flat bead comes from ample heat and wide fusion, and no bead formation implies an unstable arc—none of which match the high-speed condition.

High travel speeds in FCAW cut heat input per unit length, so the molten pool stays narrow and cools quickly. With less heat to drive broad fusion, the bead forms as a narrow, often convex shape, and the edges don’t wet evenly, giving an uneven edge profile. Deep penetration requires more heat input and thus slower speeds, a thick flat bead comes from ample heat and wide fusion, and no bead formation implies an unstable arc—none of which match the high-speed condition.