GTA pulsed current welding of thin sheets of SS304 producing superior quality of joint at high welding speed

Abstract

Thin sheets of austenitic stainless steel (SS304) are assembled using various pulse parameters of pulsed current gas tungsten arc welding. The sheets are joined with high welding speed for higher production rate, but the mean current is enhanced with higher welding speed for maintaining required heat input to get a sound joint. Application of pulsed current gas tungsten inert gas welding for joining of SS304 has been found advantageous in the form of production of weld joints with better mechanical and metallurgical characteristics. It has been observed that there can be elimination or lesser humping in weld joints. Undercut or dipped weld faces are also not found due to application of pulsed current. There is improvement of tensile strength and hardness by 12.5 and 12%, respectively. The enhanced tensile strength and hardness is justified through TEM micrograph showing presence of dislocation.