In order to investigate the difference in defect accumulation between face-centered cubic Cu and body-centered cubic Fe, tensile specimens were neutron irradiated at about 70C to fluences ranging from 4.5 x 1020 to 4.7 x 1024/m2 (E > 1MeV); corresponding to displacement dose levels ranging from some 0.0001 to 0.8dpa. Irradiated specimens were characterized by using positron annihilation spectroscopy, transmission electron microscopy and electrical conductivity measurements. A limited number of Fe specimens were also tensile-tested. At 0.0001dpa, a low density of very small vacancy clusters (1 to 3 vacancies) were detected in Fe, while larger 3-dimensional cavities were observed at higher doses. Their density and average size both increased with increasing dose level. Irradiation led to an increase in yield stress and a decrease in the uniform elongationDose Dependence of Defect Accumulation in Neutron Irradiated Copper and Iron. M.Eldrup, B.N.Singh, S.J.Zinkle, T.S.Byun, K.Farrell: Journal of Nuclear Materials, 2002, 307-311[2], 912-7

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