Application of a Modified Stress−Strain Approach for the Fatigue‐Life Prediction of a Ferritic, an Austenitic and a Ferritic–Austenitic Duplex Steel under Isothermal and Thermo‐Mechanical Fatigue

The isothermal and thermo-mechanical fatigue behavior of the ferritic–austenitic duplex stainless steel X2CrNiMoN22-5-3 is investigated in the temperature range of 100–600 °C. Furthermore, isothermal and thermo-mechanical fatigue tests on single-phase ferritic and austenitic reference steels are carried out within the same temperature range. A recently developed fatigue-lifetime description is applied and modified for all tests as well as on the different steels individually, providing appropriate fatigue-life predictions.