Microstructural evolution of Duplex stainless steel 2205 during single-point incremental sheet forming

Abstract

The research investigates different phases and grain sizes in Duplex stainless steel 2205 through single-point incremental sheet forming processes using Electron Backscatter Diffraction methodology. Research probes the changes in grain size together with counts of high-angle boundaries and low-angle boundaries and relative proportions of face-centered cubic and body-centered cubic components throughout the sample. The study evaluates base metal structural properties against three tested Sample 1 (maximum formability), Sample 2 (moderate formability), and Sample 3 (minimum formability). SEM analysis reveals that the microstructure of Duplex stainless steel 2205 undergoes substantial change due to the application of Spirit forming. The magnitude of plastic deformation applied during single-point incremental forming controls how phases transform while it affects both fault formation and grain refinement patterns. The most formable sample (Sample 1) experiences major microstructural modifications which result in improved mechanical properties. The microstructural alterations in sample 2 create intermediate formability possibilities because it possesses moderate modifications compared to sample 3 which maintains its original structure thus resulting in reduced formability. The microstructural changes during SPIF appear in X-ray diffraction patterns. Microstructural changes triggered by plastic deformation determine phase transition behavior and both microstrain formation and grain refinement results. The mechanical properties improved substantially because Sample 1 showed marked refinement in grain size alongside increased microstrain along with substantial phase transformation into martensite. The microstructural changes in Sample 2 remain moderate while Sample 3 maintains most of its original structure with minimal observed modifications. The findings are supported by transmission electron microscopy which demonstrates the link between plastic deformation along with phase changes and dislocation density as well as grain refinement processes. The microstructure of Sample 1 exhibits major changes that include high densities of dislocations while showing extensive grain refinement and transforming its structural makeup to martensite. The microstructure of Sample 3 remains largely intact while Sample 2 shows average modifications because this sample displays lower formability.