Investigations of the fatigue behavior of austenitic materials and their welded joints for RPV and core internals under HCF and VHCF, Phase II.
The aim of the subproject is to investigate and evaluate the fatigue behavior of austenitic stainless steels and their welded joints for nuclear facilities. For this purpose, fatigue tests at operationally relevant temperatures (RT and 300 °C) will be carried out on a servo-hydraulic (1 kHz) and ultrasonic (20 kHz) fatigue testing system in the VHCF regime including measurement intervals and load sequence (LCF/VHCF and HCF/VHCF) in air environment. Furthermore, the influence of frequencies and a'-martensite formation on fatigue strength at 300 °C will be systematically investigated. To evaluate the welded joint, specimens are taken transverse to the weld direction and the influence of the removal or loading direction and the heat-affected zone on the fatigue behavior will be investigated.
The project is carried out in collaboration with Materialprüfungsanstalt Universität Stuttgart and Framatome GmbH, and supported by the Federal Ministry for Economic Affairs and Climate Action.
