MICROSTRUCTURE OF THE PULSED MIG / MAG WELDED JOINTS FROM DUPLEX STAINLESS STEEL X2CrNiMoN 22-5-3

The paper analyses the structural modifications occurred in the welded joints from a Duplex stainless steel, delivered in solution annealed state in form of sheet with 12 mm thickness. As filler material it has been selected an electrode wire E 2209-16 with a diameter of 1.2 mm, which has a higher Ni content (8-10 %) compared to the base material (4.5-6.5 %) in order to promote the formation of austenite and to induce in the weld approximately equal proportions of ferrite and austenite. Also are capitalized the benefits of the pulsed current arc-welding regarding the precipitation reactions limitation of the intermetallic phase sigma and of the nitrides in weld and heat affected zone (HAZ) which can affect both corrosion resistance and toughness.