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arXiv · 1811.01422

Simulation of the atomic structure near voids and estimation of their growth rate anisotropy

A. V. Nazarov·A. A. Mikheev·A. P. Melnikov
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Abstract

We use a new variant of Molecular Static method for simulation of the atomic structure near nanovoids. In our model an iterative procedure is employed, in which the atomic structure in the void vicinity and the parameter determining the displacement of atoms embedded into an elastic continuum are obtained in a self-consistent manner. Results show that the atom displacements near nanovoids are significantly different for varies crystallographic directions in bcc metals. Not long ago we have obtained an equation of vacancy diffusion under strain. Now we use this equation and the atom displacements near nanovoids to evaluate shift of the void surface for varies crystallographic directions. We find the equation for the normal component of the vacancy flux to the surface of the sphere for some crystallographic directions and then calculate shifting rate of the void surface element in mentioned directions for the different supersaturations of the vacancies as a function of temperature.

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A. V. Nazarov, A. A. Mikheev, A. P. Melnikov. 2018-11-04. Simulation of the atomic structure near voids and estimation of their growth rate anisotropy. https://doi.org/10.1016/j.jnucmat.2020.152067

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