Effect of autogeneous GTA welding with and without flux addition on the microstructure and mechanical properties of AISI 904L joints

This study addresses the comparison of metallurgical and mechanical properties of autogeneous and activated compound flux assisted gas tungsten arc welding (GTAW) of super-austenitic stainless steel, AISI 904L. The use of compound flux containing 85% SiO2–15% TiO2 acquainted for better depth of penetration compared to autogeneous welding. Segregation of Mo rich phases was witnessed in the fusion zone of flux assisted AISI 904L. Tensile studies showed that the fracture occurred at the fusion zone for both the weldments. Ductility was found to be greater for the flux-assisted weldments. The present study also investigates the structure–property relationships of AISI 904L weldments using the combined techniques of optical and scanning electron microscopy.