arXiv subjects

I. P. Chernov

Publications and source records attributed to I. P. Chernov.

3 recordsLinked to original sources

arXiv2019

Influence of hydrogen on electron-phonon coupling and intrinsic electrical resistivity in zirconium: a first-principles study

The paper presents the first-principle calculation of the electron-phonon coupling and the temperature dependence of the intrinsic electrical resistivity of the zirconium-hydrogen system with various hydrogen concentrations. The nature of the anomalous decrease in the electrical resistivity of the Zr-H system with the increase of hydrogen concentration (at the high concentrations of H/Zr$>$1.5) was studied. It was found that the hydrogen concentration, where the resistivity starts to decrease, is very close to the critical concentration of the $δ-\varepsilon$ phase transition. It was shown that the tetragonal lattice distortion due to the $δ-\varepsilon$ phase transition of the Zr-H system eliminates imaginary phonon frequencies and the strong electron-phonon coupling of the $δ$ phase and, as a result, leads to the reduction of the electrical resistivity of the Zr-H system at a high hydrogen concentration.

cond-mat.mtrl-sci↗

arXiv2018

Mutual Influence of Different Hydrogen Concentration in α-Zirconium System with Vacancies

Hydrogen embrittlement in zirconium alloys is one of current challenges of nuclear reactor containment and can lead to a rapid decrease in mechanical properties of materials. Although many previous studies investigated the mechanism of hydrogen embrittlement at high hydrogen concentration, few studies concentrate on the mechanism at low hydrogen concentration which is before the formation of hydrides (only in the hydrogen complex state). The purpose of this study is to illuminate the formation mechanism of hydrogen complex. We calculate the formation energy Evac binding energy EH, EH-vac using ABINIT software package. For hydrogen atom at different states in lattice, we obtained Evac increased from 26.3% to 84.6% and EH-vac increased from 40.6% to 119.3%. This indicates that the bond between the original Zr atoms is weakened by hydrogen atoms entering the lattice and formation of vacancy is more possible. In addition, vacancies make hydrogen atoms and Zr atoms more closely connected and further increases the vacancies formation. Therefore, hydrogen complexes tend to expand in lattice, the brittleness of hydrogen complex becomes the main cause of hydrogen embrittlement.

cond-mat.mtrl-sci↗

arXiv2011

Synthesis of nanocrystalline titanium nitride coatings from the plasma of a composite-cathode arc discharge

Experimental data are given on the structure and properties of nanocrystalline hardening coatings of titanium nitride doped with copper, produced by plasma-assisted vacuum arc deposition by evaporating powder cathodes. A model of nanostructurization of this type of coatings is proposed. According to the model, the nanocrystallization in these materials is due to the dopant atoms, which form an amorphous sheath around a crystallite, thus defining its size.

cond-mat.mtrl-sci↗