Experimental studies on Activated Tungsten Inert Gas (32A-TIG) Welding

Abstract

Tungsten Inert Gas (TIG) welding is a process which is used in those applications requiring a high degree of quality and accuracy. However, this welding process has disadvantage of less productivity. To overcome this, Activated Tungsten Inert Gas (A-TIG) Welding is found. Experiments were performed on 304L stainless steel plates using A-TIG welding process. TIG welding fixture was designed and developed for getting fixed arc length and different welding speed. Different kinds of fluxes such as TiO2, SiO2, CaO, MnO2 and Al2O3 were used to investigate the effect of A-TIG welding process on weld geometric characteristic and distortion of weldments. A-TIG welding was carried out with different process parameters are used like welding current (60-140 A), speed (100-150 mm/min), arc gap (2 mm), gas flow rate (10 L/min), tip angle (75 degree), electro diameter (4 mm). Inverted Optical microscope with image analyzer was used to capture microstructure of weldment. A-TIG welding process parameters optimization was performed by multiobjective optimization technique named as Gray Principal Component Analysis (G-PCA). The optimum process parameters were found to be 140 A current, 100 mm/min speed and mixture of SiO2 and TiO2 flux.