Division Structural Materials
The material behaviour under operational and accident conditions is a key aspect of safety assessment of running and future nuclear installations. Structural materials are subjected to operational loads, including those resulting from the radiation field generated by nuclear fission. Neutron irradiation leads to detrimental changes of mechanical properties (hardening and embrittlement). Radiation embrittlement is a multiscale phenomenon as illustrated in the figure.
The overall objective of our research work is to elucidate the mechanisms of irradiation induced damage in Fe-based structural materials and the resulting changes of mechanical properties.
In the case of running Generation II/III reactors, we focus on long term irradiation effects in reactor pressure vessel steels arising from the life time extensions of nuclear power plants worldwide up to 80 years of operation. Materials for advanced reactor concepts (Generation IV) will be exposed to significantly higher operation temperatures and higher doses of neutron irradiation as compared to pressure vessel steels. The development and qualification of these materials is an on-going major international effort. Our work is focussed on ferritic/martensitic Cr-steels and oxide dispersion strengthened (ODS) steels. We investigate of the mechanical properties at temperatures up to 700 °C and the radiation stability. Ion irradiation is used to mimic neutrons and to study the radiation effects.
Our work contributes to the HGF programme NUSAFE and is supported by Euratom projects SOTERIA, MATISSE and M4F.
A close cooperation with the Fundamentals and Simulation Group provides additional insight to the processes at the nm scale via atomistic simulation.