AN INVESTIGATION ON JOINABILITY OF THE AISI 304 AND AISI 430 STAINLESS STEEL BY TIG, MIG AND SHIELDED METAL ARC WELDING METHODS

In this study, AISI 430 ferritic stainless steel and AISI 304 austenitic stainless steel sheets with 3 mm thickness were joined by Tungsten Inert Gas (TIG), Metal Inert Gas (MIG) and shielded metal arc welding methods. Mechanical properties of the welded samples were investigated in terms of tensile strength, notch impact strength, microhardness and microstructure. The results of the tensile test indicated that fracture occurred at the HAZ of the ferritic stainless steel side in the all samples. The highest tensile strength in welded samples were obtained in the samples joined with TIG welding. According to the notch impact test, impact energy of the samples joined with TIG and MIG is higher than that of the samples joined with shielded metal arc welding. Microhardness test showed that the highest hardness was obtained in the HAZ at the AISI 430 stainless steel for all welding condition used in this work. According to microstructure investigation, it was observed that grain growth occurred in the HAZ of the AISI 430 ferritic stainless steel.