Whiskers are most likely produced by

Whiskers are most likely produced by

• A. Pushing the wire too far ahead of the leading edge.
• B. Using excessively slow wire feed.
• C. Overheating the base metal.
• D. Too short arc length.

Answer: (A)

Whiskers come from how the molten metal is transferred and kept under control during GMAW. When the filler wire is pushed too far ahead of the leading edge of the weld pool, the arc and heat aren’t focused on the puddle, so thin strands of molten metal can form and extend forward as wispy protrusions. Keeping the wire at a proper distance so the tip is near the leading edge concentrates the heat and current in the puddle, stabilizes metal transfer, and prevents those hair-like whiskers from forming. The other options would affect bead quality in different ways rather than creating whiskers: slower wire feed changes deposition and transfer stability, overheating the base metal risks burn-through or distortion, and a too-short arc length alters heat input and arc stability but isn’t the typical cause of whisker formation.

Whiskers come from how the molten metal is transferred and kept under control during GMAW. When the filler wire is pushed too far ahead of the leading edge of the weld pool, the arc and heat aren’t focused on the puddle, so thin strands of molten metal can form and extend forward as wispy protrusions. Keeping the wire at a proper distance so the tip is near the leading edge concentrates the heat and current in the puddle, stabilizes metal transfer, and prevents those hair-like whiskers from forming.

The other options would affect bead quality in different ways rather than creating whiskers: slower wire feed changes deposition and transfer stability, overheating the base metal risks burn-through or distortion, and a too-short arc length alters heat input and arc stability but isn’t the typical cause of whisker formation.