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In modern materials science, considerable attention is given to issues which is related to the study of the properties of two-component systems, such as nickel-based and aluminum. Thus, a large number of works devoted to the study of mechanical, thermodynamic and structural properties that vary under the influence of heat treatment, as these characteristics are crucial for the formation of the necessary qualities of materials [1]. Interests arises both massive and thin-film structures because they may form intermetallic phases that provide materials specific properties as desirable and undesirable.     In this work was conducted research of dynamics of vacancies and also diffusion that occurs by means of vacancy mechanism. The aim of this work was to study the diffusion processes in two-layer nanoscale structures of Al-Ni and setting influence the concentration of vacancies on the diffusion.     Simulated crystal with defects (5756 atoms, 4 vacancies), determined the coordinates of all atoms and found displacement of atoms due to diffusion, separating them from the thermal vibrations of the atoms near equilibrium position. Determined value of the diffusion coefficient and built a graph of dependence the diffusion coefficient on temperature (Fig. 1).      Calculated values of activation energy of process, which is 590 eV, which is consistent with literature data. Established that with increasing temperature Ni diffusion is not as fast growing as diffusion Al. This can be explained fairly significant difference of the melting temperatures between components.     References:     1. Novel Ni/Al/Ni diffusion soldered joints for high temperature applications // R.K.Khanna, Institute for Physical Metallurgy, 2000.