LAUSR

Abstract The effect of the volume size factor of solute atoms and their clusters on the one-dimensional motion of interstitial clusters was studied by computer simulations. Solute atoms were placed on the migration path of the interstitial clusters, and the change in the migration energy of the interstitial clusters was obtained by the static method. The volume size factor of Au atoms in a Ni-Au binary alloy was systematically changed from −30% to +100%. When the volume size factor of the solute atoms was larger or smaller than Ni atoms, the migration energy of the interstitial clusters increased. The average migration energy required for the interstitial clusters to pass through one, two, three, and four solute atoms (volume size factor: +63.7%) was 0.57, 1.28, 2.09, and 2.47 eV, respectively. If the solute atom clusters grow and their density is sufficiently high, the jump frequency of the interstitial clusters is so low that the interstitial clusters cannot move through the solute atom clusters under an irradiation temperature of 573 K.