Effect of Pulsed Current Gas Tungsten Arc Welding Parameters on Microstructure of Titanium Alloy Welds

Titanium is one of the most important nonferrous metals, which finds extensive application in aerospace and chemical industries, because of its light weight, excellent corrosion resistance and high strength to weight ratio. Single pass gas tungsten arc (GTA) welding of thin sections of Ti-6Al-4V was accomplished with pulsing current technique and was found to be superior to conventional continuous current process in terms of grain refinement in the fusion zone. In this investigation, an attempt was made to study the effect of pulsed current GTA welding parameters on titanium alloy weld characteristics such as grain size and hardness. It was revealed that at an optimum value of 6 Hz pulse frequency and 80A peak current, the hardness was maximum and the grain size was minimum. Pulsing current in inert gas welding was found to be beneficial in titanium welding.