Study of the effect of Ni on solute clustering in α-Fe

Abstract Solute clusters can form in reactor pressure vessel steels during operation and cause the irradiation embrittlement. In this work, cluster dynamics modelling is performed to study the effect on Cu clusters of Ni addition to Fe-Cu binary alloy, assuming solute diffusion through a vacancy mechanism. The models are compared with classical theories. Also, atom probe tomography analyses are used to validate the models. It is shown that the addition of Ni to Fe-Cu alloy can enhance the nucleation of Cu clusters. This Ni effect may be contributed by the high enrichment of Ni in the nucleation phase of clusters which would decrease the formation energy of clusters.