The results of molecular dynamics simulation of the behavior of thin copper films under mechanical loading are presented. Two kinds of loading were considered: indentation and uniaxial deformation. Consideration is given to two structural states of the film, namely a defect-free single crystal and a polycrystal with a grain size of several nanometers, and two types of the substrate on which the film is deposited, namely a perfectly rigid substrate and a single crystal Al substrate. The scale effect is shown for indentation of a single crystal film. The roughness of copper film free surface retards the increase in loading curve by about the roughness depth. At the interface between the copper single crystal film and the aluminum substrate, the formation of chess-board structure has been observed. This structure plays an important role as a dislocation source decreasing elasticity limit of the composition. For the thinnest Cu films the loading curve is found to depend on the indenter position about the chess-board structure of the coating substrate interface. Cyclic deformation of Cu-Al composition destroys chess-board structure at the interface and leads to the formation of a new energetically more favorable structure with spatial dimensions depending on the thickness and length of the composition.
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