International Congress on Applications of Lasers & Electro Optics (ICALEO)
Duplex stainless steels are used in many application fields due to their outstanding performance in re-spect to strength, toughness, and corrosion re-sistance. These properties are based on a micro-structure proportion of at least a proportion of 30 \% austenite. To meet the requirements of the micro-structure and a high productivity, a high-power and precise heat controlled welding procedure like laser beam-submerged arc hybrid welding is necessary. In this study, laser beam-submerged hybrid welding processes are developed for butt joints of duplex stainless steel S31803 (t = 16 mm) using a disc laser beam source with a max. output laser beam power of PL = 16 kW. The aims of these developments are to achieve stable, efficient one-layer welding pro-cesses for joining weld seams with high quality regarding microstructure. Therefore, the welding parameter, laser beam power, welding speed and wobble amplitude, are investigated using by visual inspections and metallographic analyses. To in-crease the microstructure proportion of austenite, the laser beam is wobbled linear and transversal to the welding direction using amplitudes up to 5 mm. As results of the welding process developments, stable and efficient one-layer hybrid welding pro-cesses were archived at a high welding speed of v = 1.0 m/min and a wobble amplitude of W = 2.5 mm. The weld seams meet the requirement of at least a proportion of 30 \% austenite. Without using of the laser beam wobbling the weld seam does not achieve the austenite proportion required at this welding speed.