A multiscale concept for irradiated materials simulation is formulated based on coupling molecular dynamics simulations (MD) where the potential was obtained from ab initio data of energies of the basic defect structures, with kinetic mesoscale models. The evolution of a system containing self-interstitial atoms (SIAs) and vacancies in crystalline molybdenum is investigated by means of MD. The kinetics of formation of di-SIA clusters and SIA–vacancy recombination is analyzed via approaches used in the kinetic theory of radiation ageing. The effects of 1D diffusion of SIAs, temperature, and defect concentrations on the reaction rates are also studied. This approach can validate both the kinetic mechanisms and the appropriate kinetic coefficients, offering the potential to significantly reduce the uncertainty of the kinetic methodology and providing a powerful predictive tool for simulating irradiation behavior of nuclear materials.
The irradiation of type EP-838 austenitic stainless steel by electrons in a high-voltage microscope results in decomposition of the solid solution. The decomposition takes place in two stages. The first stage occurs as a spinodal decomposition which tends to form a lattice of rod-like precipitates along the  direction. The second stage is connected with the formation of needle-shaped precipitates oriented along the  direction.
This paper describes the results of investigations on the process of ferromagnetic layer formation on the surface of Cr-Mn and Cr-Ni austenitic steels after annealing at the working temperatures on the first wall of the thermonuclear reactor.
The presence of stable facets of nanobubbles in crystal lattice can significantly affect their diffusion coefficient, but the existing theory of this phenomenon is too general and can not take into account atomistic structure of nanobubbles in a given material. Such a theory for the mechanisms of bubble motion in crystals can be extended and developed using methods of atomistic modelling. In this work, we consider the movement of bubbles in the bcc lattice of gamma-U. The Beere’s theory of faceted bubble motion is revised and a method of non-equilibrium accelerated molecular dynamics in a pressure gradient is proposed. The results of the accelerated method calculations for gamma-U are verified using generic molecular-dynamics calculations of free nanobubble diffusion. The new method significantly accelerates calculations of the diffusion coefficient for nanometer-sized bubbles and opens the way for more accurate material-specific calculations of gas-filled nanobubbles diffusivity in nuclear fuels.
The sputtering of W-Cu composition by polyenergetic flux of hydrogen particles has been investigated. The experiments showed that the sputtering coefficients of the materials had abnormally high values in the experimental conditions.