How does travel speed influence bead shape, dilution, and heat input in GMAW?

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Multiple Choice

How does travel speed influence bead shape, dilution, and heat input in GMAW?

Travel speed controls how long the arc heats a given length of weld. With a constant current and voltage, moving faster reduces heat input per unit length, so the weld pool stays cooler and doesn’t spread as much. This makes the bead narrower and limits how much base metal melts into the weld, yielding less dilution. The shorter arc time also means less filler metal is deposited per unit length. So, faster travel lowers heat input, decreases deposition, and produces a narrower bead with less dilution. Slower travel would increase heat input and widen the bead with more dilution.

Travel speed controls how long the arc heats a given length of weld. With a constant current and voltage, moving faster reduces heat input per unit length, so the weld pool stays cooler and doesn’t spread as much. This makes the bead narrower and limits how much base metal melts into the weld, yielding less dilution. The shorter arc time also means less filler metal is deposited per unit length. So, faster travel lowers heat input, decreases deposition, and produces a narrower bead with less dilution. Slower travel would increase heat input and widen the bead with more dilution.

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