Microstructures and Mechanical Properties of Dissimilar Metal Gas Tungsten Arc Welds of 15CDV6 Steel and AISI 304 Stainless Steel

The pressure pipeline applications demand high strength steels and stainless steels based on the requirement of strength and corrosion point of view, respectively. Welding is one of the widely practiced metal joining techniques in such kind of applications due to the high-pressure environment. The present work is primarily aimed at understanding the feasibility and producing X-ray radiography quality gas tungsten arc welds of dissimilar steels, particularly, 15CDV6 steel and AISI 304 stainless steel. The sound dissimilar GTA welds are subjected to evaluation of microstructures, mechanical properties such as microhardness across the weldment and tensile properties. The mechanical properties are further correlated to microstructures of dissimilar weld joints. The filler wire material has profound influence on the microstructures and mechanical properties (both tensile strength and hardness) of dissimilar steel weld joints. The dissimilar weld made with 8CD12 filler wire demonstrated higher tensile strength and joint efficiency as compared to the dissimilar weld made with ER 308L filler wire.