Development of a novel arc welding process for obtaining beautiful wave-shaped weld bead

Abstract

　A novel arc welding process to obtain a beautiful wave-shaped weld bead was developed for welding aluminum alloys. In order to clarify the wave-shaped weld bead, it was found that it is effective to provide an arc-OFF period between two arc-ON periods for cooling molten pool. For this reason, a pulsed arc welding with high heat input was mainly performed in this process. In addition, before the pulsed arc welding a short-circuit transfer type of arc welding by a forwardly and reversely controlled wire feeding was used to reduce spatter. When welding rigid aluminum alloys, high frequency pulse without droplet detachment was also superimposed during base current period. As a result, it was found that elimination of unevenness in weld bead, avoiding convex bead, and suppression of smut could be achieved.