Enhancement of Fatigue and Cavitation Erosion Resistances of the 2205 Duplex Stainless Steel via Short-Term Phase Separation

Abstract

Short-term phase separation can strengthen the 2205 duplex stainless steel (DSS) against fatigue without shortening life across the low-cycle and high-cycle regimes, which in turn improves its cavitation erosion (CE) resistance. This strengthening is due to the reduction of cyclic plastic strains for both ferrite and austenite. For both the low and high cycle regimes, the ferrite/austenite interfaces are prime damage sites for the solution-treated condition. After undergoing phase separation, the deformation twins in ferrite become the prime damage sites. In-ferrite cracks are arrested by austenite. In the solution-treated condition, the 2205 DSS exhibits the non-Masing behavior, which will not be altered or accentuated by short-term phase separation. As far as fatigue life prediction (using the Coffin–Manson–Basquin model) and CE mass loss are concerned, the Arrhenius-type equation is usable for establishing annealing equivalence at different temperatures.