|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Continuous Phase Transformations
||Structural transformations driven by irradiation in the high defect density limit.
||Sergei L. Dudarev, Daniel Mason, Peter Derlet
|On-Site Speaker (Planned)
||Sergei L. Dudarev
Transferable interpretation of structural data is a major challenge in nuclear materials science. Quantitative models are restricted to exposure not exceeding a tiny fraction of dpa, whereas in the high dose limit, consistent analysis is difficult and interpretation relies on temperature scaling, rate theory or cluster dynamics. These models, valid in the low defect density approximation, do not treat the microscopic stresses driving structural transformations. Although intuitively it appears likely that a material might eventually reach an equilibrium state, statistically invariant with respect to the generation of new defects, the structure of such a state is not known. We find that the dynamic equilibrium state is characterised by strong fluctuations of stress and strain while largely retaining crystalline order. The defect content saturates at a fraction of a percent, and microstructure exhibits anisotropic response to external applied stress. Simulations predict unusual structural signatures of irradiation-induced transformations, well correlated with observations.
||Nuclear Materials, Phase Transformations, Computational Materials Science & Engineering