In this work, a multicriteria optimization of the technology for applying discrete coatings by electrospark alloying in the restoration of bronze parts is carried out. As criteria for optimizing the process of electrospark alloying, tribotechnical characteristics were chosen – the wear intensity and friction coefficient of the coating. As adjustable parameters, those design, technological and operational factors that have the greatest influence on the value of optimization criteria are used: coating material; lubricant; operating current; amplitude of electrode oscillations; sliding speed; specific load. As a result of experimental studies, experimental dependences of wear intensity and friction coefficient for various coating materials, sliding speeds and lubrication conditions were obtained. The use of multicriteria optimization of the electrospark alloying technology made it possible to obtain various alternative coating options and technological parameters of their application for various operating conditions. Of the studied coatings, the most effective is a two-layer coating with the first layer SP-2 and an outer layer of the base material bronze BrAZhMts 10-3-1.5, which is explained by the formation of wear-resistant areas based on Mn and Ni. Multiparametric optimization of the electrospark alloying technology made it possible to reveal a combination of structural and technological factors that ensure the formation of discrete coatings with high operational properties in the restoration of bronze parts.

In this work, the technology of 30HGSA steel ion nitriding was optimized in terms of tribotechnical characteristics – wear intensity and friction coefficient. When choosing controlled factors, the influence of all existing groups of factors that can affect the process of ion nitriding is taken into account: structural, technological and operational. Friction and wear tests were carried out under conditions that are as close as possible to the actual operating conditions of aircraft parts made of 30HGSA steel. As a result of experiments on friction and wear, tribotechnical characteristics of coatings were obtained depending on structural, technological and operational factors, respectively, to the matrix. The conducted studies showed the presence of three clearly defined zones in the dependences of wear intensity and friction coefficient on specific load at different sliding speeds and technological parameters of ion nitriding: run-in zones, uniform and catastrophic wear. The nature of samples dependences hardened by ion nitriding and heat-treated samples is similar and coincides with modern views on the laws of friction and wear processes. Analysis of tribotechnical characteristics showed the effectiveness of ion nitriding technology in comparison with traditional heat treatment. The optimal processing modes for the studied steel and triboconjugation have been established

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