Investigation of microstructure and texture evolution of nickel-saving duplex stainless steels containing Y

Microstructures and textures of nickel-saving duplex stainless steels (DSSs) containing Y were investigated. In this investigation, increasing annealing temperature (1000-1100°C) had a significant impact on the level of two-phase structure, causing an increase in the ferrite phase and a decrease in austenite phase. Y doping in DSSs inhibited the growth of recrystallized grains, leading to an obvious grain refinement during annealing. The increasing Σ13b boundaries with high mobility in Y-doped DSSs were associated with the development of {111} and {111} orientations. The Brass {011} components for austenite phase and γ-fiber textures for ferrite phase resulting from Y addition significantly improved r -values relating to excellent formability of DSSs. The excellent mechanical properties of nickel-saving DSSs containing 0.03% Y annealed 1050 °C with yield strength of 844±19 MPa, ultimate tensile strength of 1038±12 MPa and total elongation of 29.8%±0.27% were intimately linked with effective solid solution strengthening and structural refinement due to Y addition.