Microstructure and mechanical properties of the welding zone in the Corten A to St۱۲ joint by arc welding with shielded carbon dioxide

Due to the use similar welding of Corten A weathering steel and dissimilar welding of Corten A weathering steel with St۱۲ plain carbon steel in industry, the joints in the welding area were investigated. The metal arc welding method with carbon dioxide shielding gas, which is used in many cases in industry used for present work. The welding process included current and voltage control, welding wire injection rate, shielding gas rate, welding speed, connection configuration and microstructure. The mechanical properties and microstructure of the weld zone of similar and disimilar joints of Corten A weathering steel were evaluated by tensile, bending, hardness, metallographic and radiographic tests. The results showed that in the studies, the microstructure of the weld zone in similar and disimilar joints includes grainboubdry ferrite, needle ferrite and WitmannStatten ferrite. The tensile strength of the similar jointwas measured to be ۴۹۷ MPa and the disimilar joint was measured to be ۳۰۳ MPa. Weld zone hardness was measured ۲۱۰ Vickers at similar joints and ۱۸۰ Vickers at disimilar joints. In conclude, similar welding is superior to , disimilar welding in terms of strength and hardness of the weld zone.

Keywords:

weathering steel , Welding , Hardness , Mechanical properties , Microstructure.