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Information × Registration Number 0221U105906, 0120U104904 , R & D reports Title Physico-mechanical macro, micro and nano mechanisms of hydrogen interaction with low-alloy steels as a fundamental factor in the strength and performance of hydrogen storage and transportation systems popup.stage_title Head Dmytrakh Ihor M., Доктор технічних наук Registration Date 09-09-2021 Organization Physico-Mechanical Institute named after GV Karpenko of the National Academy of Sciences of Ukraine popup.description2 For the first time, the hydrogen charging of low-alloyed steels were differentiated and the quantity of hydrogen adsorbed on the metal surface, the quantity of hydrogen absorbed by the bulk of metal, and its total quantity in the specimen on the time of hydrogenation were evaluated. The influence of physicochemical conditions of hydrogen charging on the hydrogen concentration of hydrogen in the metal has been studied and the situation of electrochemical hydrogenation of the pipeline in case of damage or peeling of the protective cover, which causes its cyclic hydrogen charging-discharging, was considered. It is shown that with an increasing number of cycles of hydrogen charging-discharging, the total quantity of hydrogen absorbed by the metal increases relative to the hydrogen quantity that formed as a result of electrochemical hydrogenation. It was found that for the considered cases the preliminary hydrogen charging-discharging increases the further ability of steel to absorb hydrogen in 1.2–2.0 times. The results of the study and comparative evaluation of hydrogen charging of low-alloyed steels with different microstructure showed that the ability of steels to absorb hydrogen decreases with the transition from the pearlitic-ferritic structure to the structure of polygonal ferrite, and then to ferritic-bainite. The characteristic values of hydrogen concentration for each microstructure, which are the basis for assessing the influence of the hydrogen factor on the strength of low-alloyed steels, are established. It is shown that the applying of static mechanical stress, which corresponds to the nominal stress in the pipe wall during its operation at an internal pressure of 70 bars, significantly intensifies the hydrogenation of the studied steels: the difference between the maximum hydrogen concentration in the unloaded and stressed metal can reach more than 6 times. An experimental basic diagram „hydrogen concentration – the level of applied static stresses” was b Product Description popup.authors Dmytrakh Ihor Mykolayovych Sapuzhak Ihor Yaroslavovich Syrotiuk Andriy Mykhaylovych popup.nrat_date 2021-09-09 Close