The effect of temperature on primary defect formation in Ni-Fe alloy

Molecular dynamics (MD) simulations have been used to study the influence of temperature on defect generation and evolution in nickel and Ni-Fe alloy (with 15% and 50% Fe content) with a 10-keV primary knock-on atom (PI(A) at six different temperatures from 0 to 1500 K. The recently available Ni-Fe potential is used with its repulsive part modified by Vortler. The temporal evolution and temperature dependence of stable defect formation and in-cascade clustering processes are analysed. The number of stable defect and the interstitial clustering fraction are found to increase with temperature whereas the vacancy clustering fraction decreases with temperature. The alloy composition dependence of the stable defect number is also found for the PKA energy considered here. Additionally, a study of the temperature influence on the cluster size distribution is performed, revealing a systematic change in the cluster size distributions, with higher temperature cascades producing larger interstitial clusters. (C) 2014 Elsevier B.V. All rights reserved.