Molecular dynamics study of primary radiation damage in TiVTa concentrated solid-solution alloy

Abstract

Abstract The primary radiation damage in pure V and TiVTa concentrated solid-solution alloy (CSA) was studied using molecular dynamics method. We have performed displacement cascade simulations to explore the generation and evolution behaviors of irradiation defects. The results demonstrate the defect accumulation and agglomeration in TiVTa CSA are significantly suppressed compared to pure V. The peak value of Frenkel pairs during cascade collisions in TiVTa CSA is much higher than in pure V due to the lower formation energy of point defects. While the longer lifetime of thermal spikes relaxation and slow energy dissipation capability of TiVTa CSA can facilitate the recombination of point defects. The defect agglomeration rate in TiVTa CSA is much lower owing to the lower binding energy of interstitial clusters and reduced interstitial diffusivity. Furthermore, the occurrence probability of dislocation loops in TiVTa CSA is lower than in pure V. The reduction of primary radiation damage may enhance the radiation resistance of TiVTa CSA, and the improved radiation tolerance is primarily attributed to the relaxation stage and long-term defect evolution rather than the ballistic stage. These results can provide fundamental insights into the irradiation-induced defects evolution in refractory CSAs.