Welding is widely used in the present world in different industries like aerospace, automotive, nuclear and shipping industries, etc. Tungsten inert gas (TIG) welding plays a major role in welding of nickel alloy, aluminum, titanium and stainless steel because these are difficult to weld through other welding processes and also it offers superior weld quality. The nickel-base alloy Inconel 718 is commonly used in many industries due to its wide range of applications. Due to the selection of unsuitable welding process parameters, the weldability of In718 alloy using the TIG welding process is met with various welding defects. Therefore, these issues need to be solved to achieve better quality weld joints. By developing various variants of TIG Welding process, the efficiency of the TIG welding is improved. The present book deals with the three versions of TIG welding process which are primarily used and economical Constant Current TIG (CTIG), Current pulsed TIG (PTIG), and hybrid pulsed TIG (HPTIG). These variants of TIG Welding processes are experimented and have been described in the book to obtain the best mechanical properties like ultimate tensile strength, yield strength, etc.