One dimensional motion of interstitial clusters in Ni-Au alloy

The activation energy for one dimensional motion of the interstitial clusters was calculated in Ni-Au alloy by a static method. An EMT potential was used, which was tuned to fit the experimental volume size factor and heat of solution. The number of interstitials contained within the clusters was 1, 7 and 19. In pure Ni, the activation energies of clusters were less than 0.1 eV, and they increased with the size of the interstitial clusters. After the addition of the oversized solute atoms the activation energies increased from 0.49 eV to 0.97 eV. In neutron irradiated Ni with oversized solute atoms, the defect structures near grain boundaries, and the accumulation and absorption of interstitial clusters along the dislocations can be explained by the interactions between interstitial clusters and the oversized atoms.