Effects of irradiation temperature and dose rate on the mechanical properties of self-ion implanted Fe and Fe–Cr alloys

Authors: 
Christopher D.Hardie,Ceri A.Williams,Shuo Xu,Steve G.Roberts
Publication Details
Publication/Journal: 
J. Nuclear Materials
Publication Year: 
2013

Pure Fe and model Fe–Cralloys containing 5,10 and 14%Cr were irradiated with Fe+ions at amaximum energy of 2MeV to the same dose of 0.6 dpa at temperatures of 300C, 400C and 500C, and at dose rates corresponding to 6x10^4dpa /s and 3x10^5dpa/s. All materials exhibited an increase in hardness after irradiation at 300C. After irradiation at 400C, hardening was observed only in Fe–Cr alloys,and not in the pure Fe. After irradiation at 500C, no hardening was observed in any of the materials tested. For irradiations at both 300C and 400C, 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.