Solovykh Y. Methodological grounds for increase in the bearing capacity of functional coatings by constructive and technological methods

The subject of this investigation is technological processes for formation and constructive arrangement of functional coatings (FC). The aim of the investigation is to create "FC-base" systems characterized by predicted bearing capacity and maximal workability through optimization of technologies for constructive arrangement of coatings by criteria of strength and efficiency to be used in current engineering parts which operate under extreme conditions as well as to develop an approach to choice of alternative technologies for using FC. The methods for the investigation are based on up-to-date system analysis techniques, multifactor design of an experiment and mathematic treatment of statistical data. The estimation of the "FC-base" mode of deformation is based on analytical calculation procedures in the frame of the mechanics laws for a deformed body and techniques for numerical simulation. The theoretical and practical results include the achievement of maximal bearing capacity of traditional continuous coatings and increase in workability of the "FC-base" systems thanks to the design of novel constructive arrangements for FC, namely discrete coatings of island-like and carcass types. Novelty consists in the facts that, for the first time, a methodology for creation of "FC-base" systems with a predicted workability has been proposed. This approach is based on the development of a novel conception of systematic increase in the bearing capacity of coatings via optimization concerning strength criteria as well as via choice of alternative procedures for FC formation аnd estimation of their science linkage. A novel methodological base for investigation has been developed, which unites theoretical and experimental methods in a single complex scientific program. For the first time, constructions of discrete coatings of a carcass type have been designed and novel techniques for deposition of discrete coatings and control of FC coatings have been developed. The obtained results are as follows: mathematical modeling and optimization of processes concerning the strength criteria made it possible to increase the bearing capacity of continuous coatings as much as possible with no change in the basic technologies and equipment. The proposed physical model of the heat flow balance for plasma spraying permitted an increase in the cohesion strength and material consumption coefficient by 43% and 19%, respectively. Further increase in the FC bearing capacity was achieved thanks to design of 3D discrete coatings. The investigation results are formulated and realized in the form of recommendations concerning a systematic increase in the coating bearing capacity using such a promising universal tool as optimization and control of production and construction of FCs in relation to their strength and wear resistance. The developed scientific propositions have been implemented in industry for strengthening aircraft parts at the GP MOU "Odesaaviaremservis" (Odessa), NPP "Eltekhmash" (Vinnytsia), and H. Pisarenko IPS NAS of Ukraine (Kyiv) . The application area is mechanical engineering.