Investigation of microstructure and tensile behavior of GTAW welded duplex stainless steel 2205

Duplex Stainless Steel (DSS) 2205 is extensively utilized in marine, petrochemical, and offshore engineering applications due to its superior combination of high mechanical strength and excellent corrosion resistance. This study revealed the microstructural behaviour, and tensile strength in 2 mm thin DSS 2205 plates joined using Gas Tungsten Arc Welding (GTAW) process. Welding is completed using a GTAW method without filler metal and with optimized welding parameters having welding current of 80 A, arc voltage of 12 V, welding speed of 100 mm/min, and argon shielding gas at 15 L/min. The microstructure analysis showed the base metal has the fine microstructure for duplex steel, with almost the same amounts of ferrite (δ) and austenite (γ). In the area around the weld, the heat-affected zone a little more ferrite is found, because of the quick heating and cooling in welding. The metal of the weld first became solid as ferrite, then changed a bit to austenite, making austenite at the grain boundaries, Widmanstätten austenite, and austenite inside the ferrite grains. There is not much of the harmful metallic compounds which form, showing the welding parameters kept the material structure stable. The base metal had a yield strength of 455 MPa, an ultimate tensile strength of 735 MPa, and 25% elongation before breaking. The GTAW welded join showed a yield strength a little lower, of 430 MPa, ultimate tensile strength of 725 MPa, and 24% elongation. The findings shows that the welded join has mechanical qualities like the DSS base metal.