Publications
Showing 137 results for Author: Yuri N. Osetskiy
Aug, 2025
Journal
Beâ‚‚C as a neutron moderator for molten salt reactors: A first-principles study of structural, electronic, and defect properties
Beryllium carbide (Be2C), valued for its high neutron moderation efficiency and low absorption cross section, is a promising high-temperature neutron moderator for molten salt reactors. Its practical adoption, however, demands significant technological maturation, requiring comprehensive theoretical and experimental studies of its response to different conditions, includin…
Apr, 2025
Journal
Ab Initio Simulation of Medium-Range Ordering in Ionic Glass Electrolytes LiSiPON and LiNaSiPON
Ionic glasses can exhibit a unique combination of optical transparency, electronic resistivity, ionic conductivity, and mechanical ductility. The origin of the relatively high ionic conductivity and ductility is poorly understood. Recently, these ionic glasses were found to have medium-range ordering (MRO) similar to that of metallic glasses. This MRO significantly impacts…
Apr, 2025
Journal
Relative phase stability of L12 and DO22/DO23 structures in Al3Nb, Al3Zr and Al3V compounds
The relative stability of the different tri-aluminide (Al3M) phases in three binary systems (M = Zr, Nb and V) was assessed for their potential to form fine cubic L12 precipitates in additively manufactured alloys. Supersaturated thin films of Al-(8–30) at% M were sputtered and heat treated during in-situ x-ray diffraction (XRD) measurements to observe the temperature rang…
Oct, 2024
ORNL Report
Complete Degradation of Be2C at Conditions Expected in Molten Salt Environments
Aug, 2024
Journal
Solid breeder material crystal structure evolution due to Li burn up–Loss of crystal stability
Solid breeder materials for fusion power plants are subjected to extreme conditions of radiation damage, high temperature and designed component burn-up. The loss of lattice stability of Li2TiO3 due to Li burn-up was investigated using first principles-based approaches to aid evaluation of upper limit of component lifetime. The lattice stability is analyzed using calculate…
Dec, 2023
Journal
Local-environment dependence of stacking fault energies in concentrated solid-solution alloys
Concentrated solid-solution alloys (CSAs) based on 3d transition metals have demonstrated extraordinary mechanical properties and radiation resistance associated with their low stacking fault energies (SFEs). Owing to the intrinsic disorder, SFEs in CSAs exhibit distributions depending on local atomic configurations. In this work, the distribution of SFEs in equiatomic CSA…
Dec, 2023
Journal
Native and radiation induced point defects in AlN and Sc-doped AlN
We have performed first-principles calculations to investigate the electronic structure, configurations, formation, and binding energies of native and radiation induced point defects in pristine and Sc-doped wurtzite AlN. For the native defects, the nitrogen vacancy has the lowest formation energy in p-type material while the aluminum vacancy has the lowest formation energ…
Dec, 2023
Journal
Diffusion, atomic transport, and ordering in Al-Zr alloys: FCC and liquid phases
Additive manufacturing of materials with controlled microstructure demands knowledge of atomic scale properties near the solid-liquid transition state. Many of these properties are not affordable by experimental techniques and computer modeling is the possible solution to the problem. In this paper, we present the results of an extended atomistic study of intrinsic atomic…
Nov, 2023
Journal
On the mobility of defect clusters and their effect on microstructure evolution in fcc Ni under irradiation
µs-scale molecular dynamics studies of vacancy and interstitial clusters in fcc Ni revealed three- and one- dimensional (3-D and 1-D) modes of the cluster motion. The 1-D mobility of interstitial defects is known to enhance swelling rate. The theoretical analysis performed here suggests two novel mechanism by which the 3-D mobile clusters affect microstructure evolution un…
Nov, 2023
Journal
Two modes of screw dislocation glide in fcc single-phase concentrated alloys
Concentrated solid solution alloys (CSSAs), including medium- and high-entropy alloys, are currently being considered as prospective materials in many applications. The behavior of CSSAs under different conditions, including mechanical loading, differs from that of conventional alloys and has been the subject of intensive study by different techniques. In many cases, their…
Nov, 2023
Journal
Chemically-biased diffusion and segregation impede void growth in irradiated Ni-Fe alloys
Recent irradiations of Ni-Fe concentrated solid solution alloys have demonstrated significant improvement of radiation performance. This improvement is attributed to redistribution of the alloying elements near sinks of point defects (voids, dislocations) due to chemically-biased atomic diffusion, where vacancies have preference to migrate via Fe atoms and interstitials vi…