EVOLUTION OF VACANCY AND INTERSTITIAL CLUSTERS IN IRRADIATED ALLOY A DURING ANNEALING
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Abstract
The present work is devoted to the study of the evolution of point defects and their clusters in irradiated alloy A under subsequent isothermal annealing. The dominant mechanisms of defect interaction, including the formation of vacancy (VC) and interstitial clusters (IC), have been analyzed within the framework of diffusion theory and reaction kinetics. By applying analytical models and numerical simulations, we investigated how irradiation time and annealing temperature affect the concentration of isolated vacancies (C1v), isolated interstitials (C1i), as well as the average cluster size (Rvc-aver, Rіc-aver) and the total cluster concentration (Nvc, Nic).
The obtained results show that prolonged irradiation leads to an increase in both vacancy and interstitial concentrations, while annealing promotes their recombination and clustering. At higher temperatures, vacancy clusters become less stable, and growth of interstitial clusters is accelerated. A good correlation between theoretical predictions and experimental data was found, which confirms the reliability of the proposed model.
Particular attention was paid to the influence of defect evolution on the mechanical properties of alloy A. It was established that irradiation-induced defects significantly reduce the yield strength. However, annealing restores the plasticity due to the annihilation of point defects and restructuring of defect clusters. The dependence of yield strength variation Δσ on annealing temperature and time has been analyzed, and the role of defect stabilization processes has been discussed.
The results obtained are important for understanding the long-term stability of irradiated structural materials, as well as for predicting their performance under extreme operating conditions. The developed approach can be applied to optimize annealing regimes and to improve the radiation resistance of alloys used in nuclear power engineering and other advanced technologies.
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References
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