Abstract: The effect of active flux and arc shrinking in A-TIG welding is studied through detecting arc voltage with variant welding current. And the effect of spreading fusion of active flux on weld pool depth and arc phenomenon in A-TIG welding is also studied with properly experimental method. The results show that whether the arc of A-TIG welding shrinks is related with active flux used. The surface active flux still has the effect on weld pool depth even when arc does not shrink.

Key words: Active flux, Arc shrinking, A-TIG welding, Weld pool depth