Investigation of microstructure and mechanical properties of Nd:YAG laser welded lean duplex stainless steel joints

This research investigates welding morphology, microstructure, tensile strength, hardness, ferrite ratio and fractograph of Nd:YAG laser welded lean duplex stainless steel joints. Effect of peak power (4.4-4.6 kW), pulse duration (13-14 ms), pulse frequency (6.5-7 Hz) and speed (200-250 mm/min) on tensile strength is analysed using response surface methodology (RSM) based Box-Behnken design. Results show peak power and welding speed influence the joint strength significantly and laser welded LDSS joints have appreciable austenite-ferrite ratio and good joint strength.