Babachenko Alexander Ivanovich, Dr. Sci., (Engin.), Senior Research Scientist, Director, Iron and Steel Institute named after Z.I. Nekrasov of the NAS of Ukraine, Academican Starodubova square, 1, Dnipro, Ukraine, 49107; e-mail: a_babachenko@i.ua, ORCID 0000-0003-4710-0343

Podolskyi Rostislav Vyacheslavovich, engineer, , Iron and Steel Institute named after Z.I. Nekrasov of the NAS of Ukraine, Academican Starodubova square, 1, Dnipro, Ukraine, 49107;ORSID 0000-0002-0288-0641

Kononenko Anna Andreevna, PhD (Engin.), Senior Researcher, Iron and Steel Institute named after Z.I. Nekrasov of the NAS of Ukraine, Academican Starodubova square, 1, Dnipro, Ukraine, 49107;  e-mail: perlit@ua.fm, a_kononenko@inbox.ru  ORCID 0000-0001-7446-4105; ORSID 0000-0001-7446-4105

Safronova Elena Anatolievna, engineer, Institute named after Z.I. Nekrasov of the NAS of Ukraine, Academican Starodubova square, 1, Dnipro, Ukraine, 49107; ORSID 0000-0002-4032-4275

 

Investigation of the influence of heat treatment modes of experimental steels for new generation railway rails on mechanical properties

 

Summary. The safety of railway transport depends on the quality of the metal, the efficiency of the technology for manufacturing rails and wheelsets, and the operating conditions of the railway track. The operational durability of rails is largely determined by the structural state and mechanical properties of the metal of the rail elements. On the basis of a comparative analysis of various methods and modes of treatment of railway rails, it was found that one of the ways to increase the operational reliability of rails can be the optimization of methods for heating and cooling the metal when implementing the modes of their heat treatment. A study of the microstructure of steel laboratory melts up to 10 kg, melted under the conditions of the IHM NASU (the symbol of which is PCT), after furnace heating with cooling the blanks for tensile specimens (55x12x12mm) in various cooling media: in calm air, under a ventilator, blowing with compressor air in water with a temperature of 80˚С. It is found that at cooling rate 5,1˚С / s (cooling air compressor) is obtained a homogeneous structure of fine pearlite with a hardness of the metal at the level of foreign standards. On the basis of technical sources, it has been established that volumetric furnace heating followed by immersion of the test specimens made of steel with 0,84%С, 0,44% Si, 0,95% Mn into an environment providing the metal with a controlled cooling rate of ≈5.1˚C / s contributes to the formation of a lamellar pearlite structure with a hardness of 415 HB. It was found that the use of furnace heating leads to the production of homogeneous austenite in the volume of the samples under study.

Key words: railway rail, rail steel, heat treatment, mechanical properties

 

Reference

Babachenko O. I., Kononenko G. A., Filonenko N.YU. & Khulín A. M. (2018). Rozrobka matematichnoi modeli rozrakhunku teplovogo polya za peretinom zaliznichnoi reyki pri termichniy obrobtsi [Development of the mathematical model for calculating the thermal field at the intersection of a railroad rails during heat treatment]. Stroitelstvo, materialovedeniye, mashinostroyeniye: Sbornik nauchnykh trudov. Starodubovskiye chteniya [Construction, materials science, mechanical engineering. Collection of scientific papers. Proceedings in memory of Starodubov]. Dnipro: DVUZ “Pridneprovskaya gosudarstvennaya akademiya stroitelstva i arkhitektury”, 2018, Issue 100, 31-35. [In Ukrainian].

Skoblo T.S., Sapozhkov V.E., Aleksandrova N.M. & Sidashenko A.I. (2014). Kachestvo termicheski uprochnnnyh relsov i podkladok. Issledovanija. Teorija. Oborudovanie. Tehnologija. Jekspluatacija: Monografija [Quality of thermally hardened rails and linings Research. Theory. Equipment. Technology. Operation: Monograph]. T.S. Skoblo (Ed.). Kharkiv: TOV «Shhedra sadiba pljus», 2014, 577. [In Russian].

Petrash L. V. (1959). Zakalochnye sredy [Hardening environ]. Moskva: MAShGIZ, 1959. 114. [In Russian].

Rejki zvichajnі dlja zalіznic shirokoї kolіi. Zagalnі tehnіchnі umovi [Normal rails for full-gauge railway. General specifications]. (2005). DSTU 4344:2004. – (Chinnij vіd 2005-10-01). Kyiv: Derzhspozhivstandart Ukraїni, 2005. 31p. (Nacіonalnij standart Ukraїni). [In Ukrainian].

Relsy zheleznodorozhnye. Obshhie tehnicheskie uslovija [Railway rails. General specifications]. (2014). GOST R 51685–2013. (EN 13674-1:2011, NEQ). (Data vvedenija 2014-07-01). Moskva: Standartinform, 2014, 96 p. (Nacionalnyj standart Rossijskoj Federacii). [In Russian].

Podolskij R. V. & Dejneko L. N. (2019). Opredelenie putej povyshenija jekspluatacionnoj stojkosti zheleznodorozhnoj kolei [Determination of ways to increase the operational resistance of the railway track]. Vseukraїnska naukovo-tehnіchna konferencіja studentіv і molodih uchenih «Moloda akademіja-2019» [Proceedings from All-Ukrainian scientific and technical conference of students and young scientists “Young Academy-2019”]. Dnіpro: NMetAU, 2019, pp. 82. [In Russian].