Which of the following is a common cause of spatter in GMAW?

• A. Very short arc length.
• B. Excessive voltage.
• C. Low heat input.
• D. Proper cleaning of the workpiece.

Answer: (B)

Spatter in GMAW often comes from too much arc energy. When the voltage is excessive, the arc voltage rises, making the arc hotter and longer. That extra energy increases the heat input at the weld tip, causing the molten metal to transfer more explosively and droplets to detach and spray away from the weld pool. The result is more spatter on the workpiece and surroundings.

Other options don’t fit as well: very short arc length can lead to other problems like sticking or erratic transfer rather than spatter from high energy; low heat input tends to reduce spatter; and proper cleaning of the workpiece helps minimize contamination-related spatter.