ARC WELDING METHOD FOR Zn PLATED STEEL SHEET AND ARC WELDED JOINT

摘要

Provided are: an arc welding method that suppresses occurrences of blow holes in initial parts and final parts in a Zn plated steel sheet and reduces the occupancy ratio for blow holes in the welded part as a whole; and a welded joint. An arc welding method for a Zn plated steel sheet sets the gap between plates to 0.2 - 1.5 mm and includes a first step for moving a welding means from a welding initiation point at a first welding speed and performing welding by applying a first welding heat input, a second step following the first step for moving the welding means at a second welding speed and performing welding by applying a second welding heat input, and a third step following the second step for stopping the movement of the welding means and performing welding for 0.1 - 2 seconds at that stopped position. The first step includes welding performed on a welding unit under conditions wherein the first welding speed is less than the second welding speed and the first welding input heat exceeds the second welding input heat. In the third step, welding is performed at a welding current and a welding voltage lower than those in the second step.