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Information × Registration Number 0225U000171, (0122U002141) , R & D reports Title Scientific and methodological principles of obtaining surface nanostructures on pearlitic steels for operation in corrosive and hydrogenating environments and development of a method for their diagnostics popup.stage_title Науково-методологічні засади одержання та діагностування поверхневих наноструктур на сталях перлітного класу за їх тривалої експлуатації у корозивно-наводнювальних середовищах Head Zvirko Olha I., д.т.н. Registration Date 06-01-2025 Organization Physico-Mechanical Institute named after GV Karpenko of the National Academy of Sciences of Ukraine popup.description1 The aim of the work is to establish the basic structural parameters of formation of nanocrystalline structures (NCS) on pearlite steels by surface mechanical-pulse treatment (MPT) with alloying from technological environment, to investigate the influence of surface NCS on hydrogen permeability, wear resistance, corrosion resistance, resistance to fatigue and corrosion fatigue of steels, as well as to develop a method for diagnosing surface NCS using distribution of surface acoustic wave propagation velocity. popup.description2 It was established that surface mechanical pulse treatment of pearlite steels by multidirectional high-speed deformation allows achieving the minimum possible crystallite sizes in the range of 8–10 nm, which ensures the formation of a surface nanostructured layer of greater thickness with higher hardness, wear resistance, resistance to fatigue and corrosion-fatigue. The influence of the number of treatment cycles on the structural-phase composition of the surface nanostructure of the 65Н steel was established. It was found that the elasticity modulus of the surface nanostructure formed on U8 steel is ~ 17% higher than that of the matrix structure. It is shown that the alloying of the nanostructure during processing achieves a significant increase in wear resistance, fatigue resistance and corrosion fatigue of carbon steels. The surface alloyed nanostructured layer on the 40X steel is characterized by lower hydrogen permeability and higher hydrogen trapping efficiency compared to untreated steel, which helps to slow down the penetration of hydrogen into the material. Alloying the surface nanostructured layer on the 40X steel with nickel provides the highest hydrogen trapping efficiency as well as corrosion resistance in a 3% NaCl solution. A method for non-destructive evaluation of the parameters of surface nanostructured layers on pearlitic steels using the distribution of the velocity of surface acoustic waves has been developed and tested, which allows controlling its thickness and barrier properties for hydrogen permeation both after treatment and during operation in corrosive-hydrogenating environments. Product Description popup.authors Andreikiv Oleksandr Ye. Velykyi Petro P. Dvuliat Ihor M. Demianyshyn Nataliia M. Dolinska Iryna Ya. Dolishnyi Petro M. Zvirko Olha I. Kaniuk Yurii I. Karpiv Bohdan V. Kyryliv Volodymyr I. Klym Bohdan P. Kurylas Myroslava St.. Kurnat Ivan M. Maksymiv Olha V. Mokryi Oleh M Moskva Mykhailo I. Okrepkyi Yurii S. Pochapskyi Yevhen P. Romanyshyn Ihor M. Savytskyi Vasyl M. Semak Petro M. Stankevych Olena M. Tsyrulnyk Oleksandr T. popup.nrat_date 2025-01-06 Close