Microstructures of austenitic stainless steel weldments - a study on the effects of weld current pulsing

Ferrite morphology in austenitic stainless steel weldment fusion zone is important from the point of view of its decomposition to undesirable sigma phase and for inter granular corrosion resistance. Microstructural aspects of ferrite as affected by various frequencies of current pulsing in gas tungsten arc welding are studied along with heat affected zone structures and compared with the weldment made by continuos current. Medium pulsing frequencies were found to give desired structures in fusion zone as well as heat affected zone.