Microstructure and Corrosion Resistance of 254SMO Super Austenitic Stainless Steel Wide Arc/Double-Wire MIG Welded Joints

254SMO super austenitic stainless steel was welded by using wide arc pulse MIG welding technology,double-wire pulse MIG welding technology and normal pulse MIG welding technology, respectively, and the welding efficiency was compared. The pitting resistance of welded joints under different welding processes was detected, and the weld microstructure was analyzed by using SEM and EDS. The results show that the pitting corrosion of 254SMO joints is mainly caused by Mo segregation of unmixed zone in weld. Compared with normal pulse MIG welding, wide arc pulse MIG welding and double-wire pulse MIG welding joints have no obvious difference in joint pitting resistance performance, and the welding efficiency is 1.2 times and 2.5 times of that of normal pulse MIG welding, respectively.