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 6×10⁻⁴dpa/s and 3×10⁻⁵dpa/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.