  Pure Fe and model Fe-Cr alloys containing 5, 10 and 14%Cr were irradiated
with Fe+ ions at a maximum energy of 2MeV to the same dose of 0.6dpa at
temperatures of 300 C, 400 C and 500 C, and at dose rates corresponding to 6 x
10-4 dpa/s and 3 x 10-5 dpa/s. All materials exhibited an increase in hardness
after irradiation at 300 C. After irradiation at 400 C, hardening was observed
only in Fe-Cr alloys, and not in the pure Fe. After irradiation at 500 C, no
hardening was observed in any of the materials tested. For irradiations at both
300 C and 400 C, greater hardening was found in the Fe-Cr alloys irradiated at
the lower dose rate. Transmission electron microscopy and atom probe tomography
of Fe 5%Cr identified larger dislocation loop densities and sizes in the alloy
irradiated with the high dose rate and Cr precipitation in the alloy irradiated
with the low dose rate.
