ANALYSIS OF THE REASONS FOR SPECIFIC DEFORMATION BEHAVIOR OF TOPOCOMPOSITE OF THE ALN-D16T SYSTEM DURING INSTRUMENTAL INDENTATION

The reasons for obtaining the unloading curves of the indentation diagrams of topocomposites coated with aluminum nitride with a nonlinear section of the end of the unloading curve are investigated. The influence of the plasticity of the base and the structure of the coating of aluminum nitride of coatings deposited by the magnetron method on the base made of aluminum alloy D16T on the mechanism of deformation and destruction of the topocomposite was evaluated. The assessment of these characteristics was carried out based on the results of the analysis of model and experimental indentation diagrams of topocomposites with coatings of aluminum nitride and titanium nitride, as well as using the results of materials science studies of the behavior of materials of topocomposite components at high specific loads known in the literature. It was found that the nonlinear shape of the end of the unloading curves is associated with solid-phase structural changes in the coating material. The level of solid-phase structural changes in the coating can be estimated from the width of the hysteresis loops during repeated indentation cycles.