Microstructure, Recrystallization, and Mechanical Property Evolutions in the Heat-Affected and Fusion Zones of the Dissimilar Stainless Steels

The purpose of this study was to discuss the microstructure, recrystallization, and mechanical property evolutions in the heat-affected zones and fusion zones during dissimilar stainless steels welding. The morphology, quantity and chemical composition of the -ferrite were analyzed by using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and electron probe micro-analyzer (EPMA), respectively. The recrystallization phenomenon was evident with the second pass heat-affected zone (HAZ-2) and indicated equiaxed grains after second pass welding. The contents of -ferrite exhibited the highest value of all situations in the first pass fusion zone (FZ-1) during the first pass welding. Furthermore, the solidification mode of fusion zones transformed from massive as well as acicular ferrite into lathy and skeletal structures as increased the welding pass number from 1 to 3. [doi:10.2320/matertrans.MRA2007162]