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The nucleation and propagation of a shear band in a metallic iron glass model under uniaxial tension were studied by analyzing the quadratic nonaffine displacements of atoms. The evolution of its atomic structure was performed using statistical geometric analysis based on the construction of Voronoy polyhedra. A model was proposed based on notions about the formation of an elastic stress field equivalent to the field of a dislocation located in the area of a minimum gradient in the concentration of local shear-induced transformation centers for the nucleation and motion of a shear band.

Patterns of the generation of nanocluster icosahedral substructures of pure iron metallic glass upon quenching a melt with two competing processes, athermal nucleation and the growth of polytetrahedral local formations and their decomposition under the impact of thermal fluctuations, are investigated by means of molecular dynamic simulation.

The laws of atomic restructuring in the Cu80Zr20 metallic glass during melt quenching are studied by molecular dynamics simulation using statistical-geometrical analysis based on Voronoi polyhedra and cluster analysis. The morphology and size distribution of polyhedral nanoclusters in the glass structure are investigated.

Within the framework of the method of molecular dynamics and statistic geometrical analysis, laws governing the formation of the structure of a percolation cluster consisting of interpenetrating and mutually contacting icosahedra have been studied in the process of iron vitrification. The results of an analysis of the morphology of clusters consisting of only interpenetrating icosahedra and of the nature of their joining into a percolation cluster are presented.

The results of molecular dynamics simulation of the process of atom-by-atom growth of palladium nanoparticles are presented. The structures obtained for the Pdn clusters agree well with the results of the first-principles calculations. The low-symmetry atomic configurations for the structure of the Pd4 and Pd13 clusters have been obtained using the semiempirical potentials of the interatomic interaction for the first time.

Features of the formation of a percolation cluster structure composed of interpenetrating and contacting icosahedra during the glass transition in an amorphous Ni60Ag40 alloy have been studied using the molecular-dynamics method and statistical geometric analysis. Data on the morphology of clusters composed entirely of the interpenetrating icosahedra and on the character of their conjugation in the percolation cluster are presented.

This paper reports on the results of the molecular dynamics simulation of isothermal and isochronous annealings of binary clusters in the Cu-Ni and Cu-Pd systems. The specific features of the formation of the structure are investigated as a function of the component ratio and the cluster size. It is revealed that the Cu-Ni and Cu-Pd clusters have low and high tendencies toward amorphization, respectively. This is explained by different ratios between the atomic sizes in compositionally ordered systems.

Features in the evolution of the atomic structure of the Ni60Ag40 alloy upon quenching from a liquid disordered state were revealed within the molecular-dynamics method using many-particle potentials of interatomic interaction, calculated within the embedded atom method. It was shown that the structural stabilization of the amorphous Ni60Ag40 phase during the glass transition occurs due to the formation of a percolation cluster of interpenetrating and contacting icosahedra with nickel and silver atoms at vertices and preferentially nickel atoms at centers.

The structure of an fcc(001)/fcc(001) interphase boundary in a “nickel hemispherical crystal nanoparticle-palladium crystal substrate” system is investigated using molecular dynamics simulation with multiparticle potentials calculated in the framework of the embedded-atom method as a function of the angle of rotation of the nanoparticle. Relaxation transformations are found to occur in a component of the system under investigation with a larger lattice parameter. It is demonstrated that, under given annealing conditions, the system is characterized by a size dependence of the angle of rotation of a nanoparticle: the annealing leaves the location of large islands virtually unchanged but brings about a rotation of small nanoparticles into a parallel orientation or an orientation with a local energy minimum.

Crystallisation processes of amorphous Cu-film on Pd(001) substrate have been investigated by molecular dynamics method. It has been established that the formed structure has tetragonal distortions; the elastic stresses caused by dimensional misfit of crystal lattices of the substrate and the film lead to the formation of complex defect structure changing during the annealing.

A molecular dynamic model for instantaneously undercooled iron melt has been applied to model the isothermal annealing of the stable percolation clusters. They contain mutual penetrating and contacting icosahedra with atoms at the vertices and centers. Such stable clusters form only below the critical temperature Tg ~1180 K. We identify Tg as the glass transition temperature. It is established that the time when a homogeneous nucleation starts is minimal for Tg. The stable icosahedral percolation clusters do not form above Tg. The proposed quantitative model describes the atomic mobility in metal glasses, where root-mean-square atomic displacement is the sum of contributions from both linear (Einsteinian) and logarithmic terms, associated to irreversible structure relaxation. The activation parameters of the model change abruptly at the icosahedral percolation transition.

It is shown on the basis of the model of iron with the Pak-Doyama paired potential of interatomic interaction in the framework of the molecular dynamics method that structural stabilization of the amorphous phase of pure iron during hardening from melt is ensured by the formation of a percolation cluster from mutually penetrating and contacting icosahedrons with atoms at vertices and centers.

The atomic mechanisms and kinetics of self-diffusion of Pd adatoms on a single-crystal Pd(001) surface are investigated using molecular dynamics simulation. It is shown that the migration of Pd adatoms on the Pd(001) surface predominantly occurs through the relay-race mechanism with the participation of substrate atoms. The activation energy for an elementary event of relay-race self-diffusion is calculated from the kinetic equation describing the change in the concentration of surface adatoms labeled at the initial instant of time.

Molecular dynamic simulation with multiparticle potentials calculated by the embedded-atom method shows that a [(001)Pd–75% Pd–25% Ni solid-solution monolayer–79% Pd–21% Ni solid-solution monolayer] heterostructure is formed due to structural–morphological transformations and diffusion exchange between Ni and Pd atoms in a system of the Ni monolayer on the (001)Pd singular surface. The formation of two adjacent solid-solution monolayers ensures their coherent connection by means of elastic deformation and explains the pseudomorphism of subnanofilms with large dimensional discrepancy between the components of the original heterostructure.

It is shown that a system of classical particles considered in a molecular dynamics model with Pak-Doyama pairwise interatomic potential adequately describes not only the various structural states of iron (melt, bcc crystal, metal glass) but also the complex self-organization processes occurring in first-and second-order phase transitions (crystallization and vitrification, respectively). When the temperature is varied at a constant rate of 6.6×1011 K/s, crystallization sets in from both the amorphous and the liquid state; at a rate of 1.9×1012 K/s, crystallization is observed only in the amorphous state; and when heated at a rate of 4.4×1012 K/s, the model amorphous iron transfers to the liquid state without crystallization. The energy of homogeneous formation of a crystal nucleus in the bulk of the amorphous phase of iron is calculated to be ∼0.71 eV under the assumption that there is a spectrum of activation energies.

The model of iron with Pak-Doyama pair interatomic potential was used as an example to demonstrate by molecular dynamic calculations that the structural stabilization of an amorphous phase of pure metals is due to the formation of a percolation cluster composed of the interpenetrating and mutually contacting icosahedra whose vertices and centers are occupied by atoms.

The structure of the (001) fcc/(001) fcc interphase boundary of a system consisting of a hemispherical Ni (or Cu) crystal nanoparticle and a Pd crystal substrate was studied depending on the nanoparticle rotation angle θ = 15°, 20°, 25°, and 30°. A molecular dynamics simulation including multiparticle potentials calculated in the framework of the embedded atom method was used in this study. It was shown that, under given annealing conditions, the nanoparticle rotation depends on the size; namely, the annealing of small nanoparticles leads to their rotation to the position corresponding to the coincidence orientation at the interphase boundary, while the position of large islands remains practically unchanged. It was established that the atomic rearrangement at the interphase boundary affects only lattices with a larger parameter.

The isochoric heating of amorphous iron at an average rate of about 6.6×1011 K/s was modeled by the molecular dynamics method using the approximation of Pak-Doyama pair potential. The bcc crystallization of the model system was found to occur in the temperature range 1100–1180 K.