Developments and Improvements Using Hot Wire Gas Tungsten Arc Welding – A Review

Abstract

Gas tungsten arc welding (GTAW) is a high quality welding process widely used in most industries. However, the process is limited to higher welding speed and higher deposition rate. To overcome this limitation, the GTAW process is modified in such a way that filler metal is heated prior to entering into the weld pool. This heating is carried out by resistance heating. Hot wire GTAW (HW-GTAW) ensures the availability of arc energy to melt the base metal. This results in an increase in deposition rate and additionally, increases the welding speeds to a large extent. Welding is an important form of joining materials and is most significant for the application of structural components. This paper reviews the application of the hot wire technique during conventional GTA welding, thereby providing the benefits in terms of metallurgical control, energy efficiency and rate of deposition. This process has the potential to achieve high efficiency and welding faster with lower heat input. The HW-GTAW process is widely used in welding various novel materials and it is a promising alternative to the conventional GTAW process with lower heat input and narrower heat affected zones. This process not only eliminates the various defects in the weld joints but also increases productivity in industries.