Thermo-mechanical fatigue behavior of reduced activation ferrite/martensite stainless steels

Blanket modules of a future nuclear fusion reactor are subjected during service to alternating thermal and mechanical stresses as a consequence of the pulsed reactor operation. Therefore, the thermo-mechanical fatigue (TMF) behavior of reduced activation ferrite/martensite stainless steels, as its structural material, is examined. TMF results of as received EUROFER 97 show a remarkable reduction in life time compared to isothermal low cycle fatigue (LCF) tests. The application of hold times in TMF-experiments leads to different damage reactions than during LCF loading. Microstructural evaluation during both cyclic loading procedures is very similar and gives no indication of the different damage behaviors.