Tensile properties and microstructure of 590 MeV proton-irradiated pure Feand a Fe-Cr alloy

Polycrystalline pure Fe and Fe-12Cr alloy have been proton-irradiated to do ses of 10(-3)-3 x 10(-1) dpa at room temperature and 523 K. Samples were me chanically tested in tension and transmission electron microscopy (TEM) was performed on the as-irradiated material as well as on the irradiated and d eformed material. At room temperature, pure Fe presents an initial yield po int, that increases with the dose, followed by a yield region, indicative o f a localized deformation mode. The Fe-12Cr alloy shows the same behavior, but the irradiation amplifies the effects previously mentioned. No yield po int or yield region appears after irradiation at 523 K. TEM observations of the irradiated material showed a high density of small defect clusters whi ch increases with the dose. Defect-free channels are observed in Fe-12Cr ir radiated and deformed at room temperature. Results of the present investiga tion are compared with neutron irradiation of similar materials. (C) 2000 E lsevier Science B.V. All rights reserved.