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This paper presents the results of testing a wear-resistant ceramic coating on the work surface of an internal combustion engine (ICE) cylinder’s sleeve. A combined coating formation technology is described that consists in applying an aluminum layer to the sleeve’s work face by gas dynamic spraying and then covering this face with a ceramic layer by microarc oxidation (MAO). A tenfold reduction in the reinforced sleeve has been determined by the accelerated comparative wear rig tests of reference (new) sleeve-piston ring coupling specimens and reinforced specimens with a combined coating. The supplementation of nanoparticle admixture to MAO coating reduces the friction factor between the cylinder sleeve face and the piston ring by 25-30%. The proposed technology can be used to reinforce work surfaces of new cylinder sleeves and recover worn out ones.

The application of various types of functional and protective coatings made of inorganic materials to parts made of conventional structural materials will be able to solve the issue of ensuring the planned service life of modern devices, machines and mechanisms. Electric arc metallization, characterized by relatively high productivity and low cost of coating, serves as one of the methods of applying gas-thermal coatings. However, the high porosity of the resulting coatings, their low adhesion strength to the substrate and plastic properties prevent the widespread use of this method. (Research purpose) The research purpose is in studying the chemical, thermal and mechanical effects on samples obtained by electric arc metallization, on the adhesive, cohesive and strength properties of the coating and the areas of connection of the coating with the substrate. (Materials and methods) The authors used electric arc metallization and gas-dynamic spraying to obtain the necessary coatings. A mechanical effect on the coating was studied using the machine IZH- 250TV and special research equipment to determine the properties of coatings and substrates. (Results and discussion) Gas-thermal coatings can be successfully used in the manufacture of new and restoration of worn parts of agricultural machinery. The processing of metallized samples by surface plastic deformation are expedient and necessary. Chemical and thermal treatment has a positive effect on the properties of the coating and the substrate, increasing the value of microhardness by 50-70 percent. The use of supersonic metallization devices leads to an increase in adhesive strength by 30-35 percent. (Conclusions) The study showed that chemical and thermal treatment has a positive effect on the properties of the coating. Plastic deformation of the sprayed surfaces is practically equivalent to thermodynamic effect. It is recommended to use plastic deformation for spraying cylindrical surfaces.

The results of development and implementation of software and technical solutions for assembly process control at the level of production shop and site at industrial enterprises are presented. The main basic software modules and their relationship in the production process are installed. Specific examples of practical software implementation in the current production are shown.

The authors consider theoretical foundations of the coating formation when using the no-bath method of microarc oxidation (MAO) as applied to a point counter electrode. The relationships between the growth rate of the coating thickness and the electrical, geometric and chemical parameters of the MAO process have been mathematically determined. An algorithm for calculating the productivity of the MAO process, due to the growth rate of the coating thickness has been developed. The off ered methodology for the experimental selection of modes of the no-bath MAO of aluminum alloys with an electrically neutral nozzle was verifi ed to obtain a coating on a small area of a part with a fl at surface. In the experiment, with a constant “Nozzle-Workpiece” distance equal to 10 mm, the distance “Electrode-Workpiece” took the values of 5, 10, 20, 30 mm. As a “fl at” surface, the authors took the end face of a 50 mm rod made of the D16T alloy based on aluminum, and a rod made of the 08Kh18H10T steel with a diameter of 6 mm served as an electrode. Use was made of the composition applied in the bath method which included an electrolyte: 8 g of KOH, 30…35 g of Na2SiO3, 1 g of artifi cial diamond nanopowder per 6 liters of distilled water. The duration of the MAO process was 120 min. It has been experimentally established that an increase in the “Electrode-Workpiece” distance decreases the potential for coating formation, which decreases the current in the electrochemical circuit. The analysis of the MAO coating thickness has revealed that 5…15 mm is the optimal distance from the electrode and nozzle to the workpiece, which ensures a stable coating thickness of more than 100 microns on an area equal to or greater than the cross-sectional area of the nozzle supplying electrolyte. The expediency of using the developed mathematical model and the methodology for selecting the process modes with the no-bath method of microarc oxidation has been experimentally confi rmed. The experimental studies have established that the proposed scheme of the MAO process provides an increase in the productivity (the thickness growth rate) of coating deposition by 20% and a decrease in energy consumption by 25%.