Mechanical and microstructural behaviour of isothermally and thermally fatigued ferritic-martensitic stainless steels

A.F. ARMAS; C. PETERSEN; R. SCHMITT; M. AVALOS; I. ALVAREZ ARMAS

Baden-Baden, Germany

Conferencia; 10 International Conference of Fusion Reactor Materials; 2001

Structural components of a DEMO-test blanket are subjected during service to alternating thermal and mechanical stresses as a consequence of the pulsed reactor operation in e.g ITER-FEAT. Of particular concern is the fatigue endurance of Reduced Activity Ferrite/Martensite (RAF/M) steels like the Japanese steel F82H mod. and the European heat EUROFER 97 under cyclic strains and stresses produced by these temperature changes. The microstructural behavior of these materials during cycling deformation shows critical damage paths. In the present paper isothermal Low Cycle Fatigue (LCF) and thermomechanical fatigue result in the temperature range 723 to 873K of the RAF/M steel F82H mod. and EUROFER 97 are compared to those of the conventional ferrite/martensite steel MANET II.-