Tkachenko K. Improvement of chemical compositions and heat treatment technologies for alloy steels inclined to hydrogen embrittlement and flakes formation

Subject of inquiry is alloyed rolled steel product disposed to hydrogen embrittlement and flake formation.Subject of investigationis is influence of chemical elements,nano-,sub- and microstructural states of steels on solubility and diffusive behavior of hydrogen.A purpose is raising of steel resistance to hydrogen embrittlement and flake formation due to the scientifically founded alloying and forming by heat treatment structural states with prescribed parameters of diffusive behavior of hydrogen.Methods-volumetric,electrochemical and dilatometric methods of hydrogen behavior determination;X-ray structure analysis;standard tests of mechanical properties;methods of statistical analysis of data,computer experiments,software product Hydrogen Analysis v2.1.Novelty:it was found that levels of main physical,thermochemical properties and solubility of hydrogen in Fe and IV-period metals is directly determined by the charges of electrons of external levels.Obtained dependences was used for prediction of the state of these metals solutions,also for concentration dependences of hydrogen solubility expected in hard solutions of IV-period metals in Fe.It was extended and refined information in relation to influence of industrial steels chemical composition on hydrogen solubility.New information was obtained in relation to: influence of sub- and microstructure of pipe steels on low temperature solubility and diffusive behavior of hydrogen in metals; influence of hydrogen on mechanical properties of rolled tube steel products in a delivery state.Results:Software was created for a computer modeling of hydrogen degassing processes in metalware.Recommendations are developed:on perfection of chemical composition and antiflake treatment (AFT) of industrial tube steels with the purpose of negative hydrogen effect reduction;on increase of X60 steels firmness to hydrogen penetration during the exploitation;on optimization of railway rails and grindings balls AFT technologies.