Among all the welding processes, the chief advantages in using Gas Tungsten arc welding (GTAW) for surfacing are high reliability, all position capability, ease of use, low cost and high productivity. With the growing emphasis on the use of automated and robotic system GTAW welding, with its all position capabilities, has been employed increasingly in mechanized surfacing in industry. It is reported that the strength of a welded joint is largely determined by the dimensions and shape of its bead. The profile of the bead has significant influence on the welding. From the cross-sectional area of the bead, the cooling rate of the weldment can be judged. Bead cross-sectional area along with the bead height (BH) and width determines the residual stresses and thus, distortion of the welded structure. Weld cracking is also related to the profile of the bead. Moreover, a considerable amount of micro-structural change occurs in the welded zone. The size of the grains in the welded zone is generally found to be larger than that of the base metal. Due to the above reasons, the mechanical properties of welded structure are dependent on the size and shape of the weldment. The effect of process parameters such as arc voltage, welding speed, welding current, type of shielding gas, shielding gas flow rate are considered in this review paper for GTAW.
GTAW, Process Parameters, Arc voltage, Welding speed, Welding current, Type of shielding gas, Shielding gas flow rate
