HARDENING BEHAVIOR OF ADVANCED STRUCTURAL ALLOYS UNDER ION IRRADIATION

In this study, a series of recently developed alloys, including multi -principal element alloys with FCC and BCC phase structure, ODS-modified austenitic steel, and T91 ferritic-martensitic steel modified with severe plastic deformation have been investigated with respect to the hardening/embrittlement phenomenon under irradiation. Samples of all materials were irradiated under identical conditions with 1.4 MeV Ar ions at room temperature. Transmission electron microscopy (TEM) was used to characterize the radiation defects and microstructural changes. Nanoindentation was employed to measure the effect of ion irradiation on hardening. The dependence of the hardening parameters on the irradiation dose, their relationship with the evolution of the microstructure was studied. It was found, that the developed alloys exhibited a reduced susceptibility to irradiation induced hardening compared to that of conventional SS316 and 18Cr10NiTi stainless steels. The study discusses the mechanisms that can affect the radiation hardening behavior in examined materials. PACS: 61.80.-X, 81.40.CD