Ion-irradiation-induced damage of steels characterized by means of nanoindentation

Self-ion irradiation was used to simulate the damage caused by fast neutrons in the austenitic stainless steel SS 304 SA, the ferritic/martensitic steel Eurofer’97 and a Fe–9 at.%Cr model alloy. The irradiation-induced hardness change in the damage layer was evaluated by means of nanoindentation. Three-step irradiations were performed at room temperature and 300 °C up to 1 and 10 dpa. An irradiation-induced hardness change was shown for all materials. No influence of irradiation temperature could be resolved. Irradiation-induced hardening exhibits different fluence dependencies in Eurofer’97 and Fe–9 at.%Cr. While the data indicate a saturation-like behaviour for Fe–9 at.%Cr, an increase of hardness with fluence up to 10 dpa was found for Eurofer’97.