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Information × Registration Number 0224U001239, 0122U000771 , R & D reports Title Development of new methods for surface nanostructuring of steel surfaces with predictable quality parameters based on the method of electrospark alloying popup.stage_title Head Haponova Oksana P., Доктор технічних наук Registration Date 19-01-2024 Organization Sumy State University popup.description2  The aim of the project is to develop a method for controlling the structure and properties of the working surfaces of steel parts by nanostructuring through electrospark alloying (ESA). The main mechanisms of nanostructure formation in the modified layer during ESA have been determined using metallographic and X-ray analysis methods. An effective way to form nanoscale phases in the coating is to introduce a special technological medium (STM) containing nanoparticles into the interelectrode area. It has been proved that during molybdenation of steel surface and armco iron by ESA method using STS containing nanotubes, a microstructure of strengthened coating layer reinforced with nanophases is formed. The formation of a nanostructure helps to increase the hardness and wear resistance of the coating. ESA regimes are determined in which the Mo+S coating has the best tribotechnical properties due to the presence of molybdenum disulphide. The developed methods are recommended for the formation of self-lubricating working layers on the working surfaces of responsible, wearing parts. The change in structure and phase state of high entropy alloys during ESA is analysed. High entropy alloy (HEA) coatings were obtained by the electrospark alloying method. X-ray diffraction analysis revealed that the coatings obtained have a nanoscale modulated structure and high hardness. Tribological studies showed that the wear resistance of the obtained materials increased up to 40 times, depending on the indenter and test conditions. The HEA coating resulted in a 1.5 to 3-fold reduction in friction coefficient. A mathematical-analytical model of electrospark coating formation using the iterative-recursive method was developed. Based on the experimental and theoretical results, recommendations for the development of technologies to increase the durability of important machine parts by ESA methods are proposed Product Description popup.authors Haponova Oksana P. Zhylenko Oleksandr I. Zhilenko Tetyana I. Zahorulko Andrii V. Martsynkovskyy Vasyl` S. Myslyvchenko Oleksandr M. Okhrimenko Viktor O. Tarelnyk Nataliia V. Tiahno Serhii V. popup.nrat_date 2024-01-19 Close