arXiv subjects

M. S. Veshchunov

Publications and source records attributed to M. S. Veshchunov.

4 recordsLinked to original sources

arXiv2026

Effect of ballistic re-solution on the nucleation kinetics of precipitates in diluted binary alloys under irradiation. Part 1: Stoichiometric gamma' precipitates in Ni-Al alloys

A modification of classical nucleation theory is carried out as applied to solid solutions under irradiation, taking into account the influence of ballistic re-solution on the nucleation kinetics of pure unary (single-component) and stoichiometric binary precipitates. The effects of excessive point defects formed under steady irradiation conditions and operating alongside the ballistic re-solution mechanism are incorporated into the new model for a consistent description of the nucleation of incoherent and coherent particles. The developed model was applied to interpret the results of Nelson, Hudson and Mazey (NHM) tests, in which the stability of gamma' phase (Ni3Al) precipitates in diluted Ni-Al alloys under irradiation was studied.

cond-mat.mtrl-sci↗

arXiv2026

Effect of ballistic re-solution on the nucleation kinetics of precipitates in diluted binary alloys under irradiation. Part 2: Cr-rich alpha' precipitates in Fe-Cr alloys

On the base of a critical analysis of existing models for nucleation of new phase precipitates in metastable binary alloys, a new kinetic model of homogeneous nucleation and growth of alpha'-phase precipitates in Fe-Cr alloys was developed within the framework of the Reiss kinetic theory of binary nucleation. The model was further modified to account for the influence of ballistic re-solution on the kinetics of nucleation and growth of alpha' precipitates, following the general approach proposed in Part 1. The model was used for qualitative interpretation of the results of recent tests, in which the stability of alpha' precipitates in Fe-15Cr alloys under irradiation was studied.

cond-mat.mtrl-sci↗

arXiv2024

On the kinetics of homogeneous nucleation of incoherent precipitates in solid solutions

By critically examining the traditional theory of homogeneous nucleation of precipitates in solid solutions, it is revealed that the theory's assertion regarding an increase in the nucleation free energy due to elastic strain associated with the difference in atomic volumes between the two phases is applicable to coherent precipitates, but becomes incorrect when applied to incoherent precipitates. This conclusion is obtained by accounting for thermal point defects in the matrix, which can be absorbed at the interface between an incoherent particle and the matrix during nucleation, thereby relieving elastic stresses. Accordingly, a new kinetic model based on the Reiss theory for binary nucleation is proposed for predicting the nucleation rate of incoherent precipitates by agglomeration of solute atoms and point defects, with a further extension to account for excess vacancies formed under non-equilibrium conditions of quenching experiments.

cond-mat.mtrl-sci↗

arXiv2023

Development of the Reiss theory for binary homogeneous nucleation of aerosols

The Reiss theory for binary homogeneous nucleation in binary gas mixtures is critically analysed and further developed. Based on the analysis of phase space trajectories in the supercritical zone of the phase transition, carried out within the framework of the theory of two-dimensional dynamical systems and supplemented by the flux matching condition at the boundary of the critical zone, it is shown how the theory should be modified. The proposed modification is equivalent to the earlier modifications by Langer and Stauffer, based on additional trial assumptions (ansatz) for solving the steady state equation for the non-equilibrium size distribution function, but reveals and substantiates the approximation underlying their approach. The extension of the Reiss theory to binary vapours in inert carrier (atmospheric) gases is justified.

physics.chem-ph↗