Determination of threshold energies for displacements of Fe and Rh atoms in Fe-50 at.%Rh intermetallic compound by using energetic electron irradiation at low temperatures

Changes in electrical resistivity induced by irradiation with energetic electrons were measured for Fe-50 at.%Rh alloy as a function of electron energy in the range from 0.5 to 2.0 MeV. The irradiation was carried out below 20 K and the resistivity was measured at 10 K. The electron energy dependence of the resistivity change rate was analysed by using a simple displacement theory, and the average threshold energies for atomic displacements, Ed, were determined as 30 eV for Fe and 45 eV for Rh. The analysis also revealed that resistivity values for Frenkel pairs, ρF (in units of μΩ cm per at.%) were 128 and 181 for Fe atom and Rh atom, respectively. The experimentally determined values of Ed and ρF can be used for the quantitative estimate of defect concentration in Fe-50 at.%Rh irradiated with energetic particles.