Mechanical and Microstructural Investigation of Dissimilar S235 and S32205 Steel Sheets After TIG Welding

Abstract

S235 unalloyed steels are broadly used in structural and constructional applications while UNSS32205 duplex stainless steel alloys are preferred especially in bridges, marine and pulp, paper production industries. These two distinct types of steel alloys can be both used in applications especially for economical considerations assuming that high alloyed UNS S32205 steel is more expensive as compared to S235 alloy. These alloys can be joined together with fusion welding operations such as Tungsten Inert Gas Welding technique. Welding of these alloys are referred as white and black welding technique as a result of white and black designating stainless and low alloyed steels respectively. In this study, S32205 and S235 steel sheets both having thicknesses of 3mm were joined by TIG welding with pure argon shielding gas. Micro-structural investigations, micro-vickers hardness and tensile tests were made on raw materials and welded joints. As tensile and micro-vickers hardness tests are both considered, dissimilar welded joints exhibited close hardness and strength values with raw materials.