Self-Point Defect Trapping Responsible For Radiation Swelling Reduction In V-Ti Alloys

The very low swelling of V-Ti alloys under neutron irradiation is a poorly understood phenomenon. To uncover the underlying mechanism of swelling reduction, we performed density functional theory and molecular dynamics simulations with a V-4% Ti random alloy with interatomic potentials. We find that titanium solutes efficiently trap vacancies and self-interstitial atoms. Exceed vacancies conserve their individuality, forming a variety of complexes with Ti solutes compared to their association into a dislocation loop in pure V. Randomly distributed Ti-vacancy complexes are much more appropriate for efficient point defect recombination as opposed to the localized dislocation loop formed in pure V.