Influence of electrode rotation speed on geometry and internal structure of weld beads in rotary TIG wire-arc-directed energy deposition

This study investigates the effects of varying the electrode rotational speed in rotary tungsten inert gas (rotary TIG), a novel wire arc additive manufacturing technology. Rotary TIG aims to mitigate the directional nature of the TIG WAAM process, producing weld beads with uniform cross-sections conducive to additive manufacturing. Scripts were developed to analyze the characteristics of deposited single bead profiles. The results demonstrate that increasing the electrode rotational speed leads to increased height at the expense of the width in the weld bead profiles. Additionally, rotary TIG weld bead profiles exhibit a parabolic shape and a geometry forecast model was developed. The effect of electrode rotation speed has been magnified; a metallurgical analysis reveals that the internal structure loses its uniformity as the rotational speed decreases. Furthermore, a thermofluidic dynamic simulation was developed to replicate the rotary TIG welding process. This simulation confirms that electrode rotation speed impacts geometry, aligning with experimental findings.