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Information × Registration Number 0221U000175, 0120U102312 , R & D reports Title Development of physico-technological bases of formation of superhard innovative nanolayers coatings on treated ions surfaces in gas plasma popup.stage_title Head Voyevodin Viktor M., Доктор фізико-математичних наук Registration Date 03-01-2021 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2  The research report contains 61 pages, 33 figures, 5 tables, 59 references. Objects of research - nanolayer vacuum-arc nitride coatings on ion-treated surfaces in gas plasma and substrates made of different steels. The purpose of the work is to establish the mechanisms of adhesive interaction of nanolayer nitride coatings with a substrate made of different steels after ionic nitriding at different technological parameters of the process. Research methods - computer modeling, hardness measurement, determination of elasticity and yield strength by indentation method, determination of adhesive strength and coefficients of friction, X-ray structural studies, electron microscopy. Computer three-dimensional and two-dimensional modeling of nitrogen redistribution after ionic nitriding of test specimens from different steels taking into account the phase conversion of ε-nitride to nitrogenous austenite showed that the conversion at 860 ° C occurs in 3.25 minutes. The nitride layer, despite its gradual dissolution, reduces the average concentration profile of nitrogen in austenite. However, the depth of diffusion saturation, which gives a marked increase in microhardness, does not significantly reduce. According to the simulation data, nitrogen diffusion to a depth of up to 750 μm requires almost temporary holding at the quenching temperature. Coatings formed on substrates with a pre-applied chromium sublayer have a higher hardness (H = 36.5 GPa) compared to similar samples without such a sublayer (H = 30.0 GPa). The presence of a chromium sublayer also helps to increase the adhesive strength of the coatings of the system (TiAlSiY) N / CrN on substrates made of steel X18H10T. The critical values of the fracture load for coatings with a sublayer of chromium reach the value of LC5 = 188.6 H, and without a sublayer of chromium - LC5 = 150.1 H. Key words: ionic nitriding, nanolayer coatings, multicomponent coatings, nitrides, hardness, computer modeling. Product Description popup.authors Andreev Anatolii O. Voyevodin Victor M Dolomanov Andrij V. Domnich Vjacheslav M. Kovteba Dmitro V. Serdiuk Iryna V. Stolboviy Vyacheslav O. popup.nrat_date 2021-01-03 Close