Welding Metallurgy Practice Test 2026 – The Complete All-in-One Guide to Exam Mastery!

Low arc voltage in FCAW shortens the arc length, concentrates heat, and promotes a more erratic metal transfer. This tends to create a bead that sits up above the weld surface (convex) and develops a ropey, stringy surface texture as metal transfers in pulses rather than as a smooth, steady pool. The aggressive, short arc can also cause the electrode to momentarily stick to the weld pool or base metal, leading to stubbing.

That combination—convex shape, ropey surface, and potential stubbing—fits low-voltage FCAW behavior. In contrast, a flat, smooth bead, a very narrow defect-free bead, or a stable arc with uniform deposition point to higher voltage or different transfer dynamics that produce more controlled, smoother weld beads.