Moscow Aviation Institute (National Research University), Moscow, Russia

L. N. Lesnevsky, Professor of the Department of Aircraft Engine Manufacturing Technology, Doctor of Technical Sciences, e-mail: l.lesnevskiy@yandex.ru
I. A. Nikolaev, Senior Lecturer of the Department of Aircraft Engine Manufacturing Technology, Candidate of Technical Sciences, e-mail: nikolaevia@mai.ru
E. A. Astafev, Student, e-mail: astafev-elisey@mail.ru
N. S. Timofeev, Student, e-mail: nstimofeev@mai.education

Self-fluxing alloys, namely NiCrBSi alloys, are known to have a set of special properties: high corrosion and erosion resistance, and wear resistance in various operation conditions. There are different coating methods, but the most widely used one is two-stage technology of a plasma spraying and subsequent fusing of the coating. The research is aimed at studying fretting wear of the NiCrBSi alloy deposited by a modernized single-stage process of arc spraying (metallization), using powder wire of an ultra-low diameter, 0.8–1.2 mm. Having compared loads and displacements of fretting loops achieved within a set range, the authors assessed the mechanism and nature of fretting wear proved by a subsequent analysis of the microstructure and morphology of wear spots studied with Olympus LEXT OLC500, a confocal optical microscope. The produced coatings are characterized by high density, no lamellar structure, and a minimum number of pores. The paper compares volume wear during fretting according to the diagram of ball – plane under various loads and displacements, and contains values of friction coefficients and achieved values of coating microhardness. A comparison of tribologocial characteristics of NiCrBSi alloy coatings and an uncoated substrate from AK4-1 aluminum alloy coatings showed considerable improvement in characteristics of bulk wear, and the friction coefficient of the system in the set operation conditions.
The authors express their deep gratitude to Sergey Nikolaevich Sarbuchev (LLC Thermal-Spray-Tech) for his help in developing and implementing a coating forming process by a method of arc spraying.

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