Assessment of Dissimilar Weld Between Duplex Stainless Steel Grades for Severe Corrosive Applications

This paper deals with the investigations on dissimilar weld between two duplex stainless steel grades AISI 2205 and AISI 2507. Increasing use of duplex stainless steel grades instead of austenitic stainless steel grades are growing day by day. This study is an effort in this direction in particularly focusing the dissimilar welding of super duplex stainless steel (AISI 2507) and commercial duplex stainless steel (AISI 2205) grades. Gas tungsten arc welding process was used in this study to fabricate the defect free weld plate. Microstructural analysis on dissimilar weld was carried out to study the diffusion of alloying elements. Micro hardness analysis, Charpy impact toughness test, tensile test and formability test were carried out and the properties were compared with their corresponding base metal properties. Hot corrosion test was carried out to study the feasibility of dissimilar weld in severe corrosive applications. The findings of this paper try to fulfill the applications where commercial duplex stainless steel grades are frequently gets affected in the weld region due to the severity of corrosive environments and due to the sacrificing weld properties.