Effect of vibration and hot-wire gas tungsten arc (GTA) on the geometric shape

Bead-on-plate experiments were carried out, and the weld-bead size and shape were compared and discussed. The welding droplet parameters were measured by a high-speed camera. A computation fluid dynamics (CFD) model utilizing VOF (volume of fluid) method, incorporating the experimental droplet parameters has been developed to understand the weld pool dynamics and subsequent weld pool geometry. From the experimental results, a narrower and deeper penetration was observed with hot-wire while wider and shallow penetration was observed with cold wire gas tungsten arc welding (GTAW). The developed model has been applied to predict and analyze the mechanism for narrower and deeper penetration. A modified relationship has been established for droplet detachment in hot wire GTAW.