Influence of Heat Treatment on the Microstructure and Low-Temperature Performance of Low-Carbon Steel
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In the present work, 20L and 20GL steels are investigated with a view to increase in their impact strength at negative temperatures, by adjusting the structural state in final heat treatment of valve and pipeline components. Stable impact strength KCV may be established in 20L steel at –40°C and in 20GL steel at ‒60°C by three-stage heat treatment: double quenching in water and subsequent high tempering. The other three heat treatments considered proved ineffective. The greater strength of 20GL steel components in comparison with 20L steel components may be attributed to its finer structure and greater bulk content of acicular α phase, on account of the higher content of manganese, which deters the ferrite transformation of austenite.
Keywordspipeline components valve components heat treatment critical interval microstructure impact strength
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- 1.Solntsev, Yu.P. and Titova, T.I., Stali dlya Severa i Sibiri (Steels for the North and Siberia), St. Petersburg: Khimizdat, 2002.Google Scholar
- 2.Primerov, S.N., Vel’misov, V.V., Murzin, E.S., et al., Improvement of steel quality for castings of fittings, Lit’e Metall., 2004, no. 1 (29), pp. 96–97.Google Scholar
- 3.Smirnova, Yu.A. and Andreev, A.K., Improvement of cold-resistance of steel castings, Materialy 6-i mezhdunarodnoi nauchno-prakticheskoi konferentsii “Sovremennoe Mashinostroenie: Nauka i obrazovanie” (Proc. Sixth Int. Sci.-Pract. Conf. “Modern Machine Engineering: Science and Education”), Evgrafov, A.N. and Popovich, A.A., Eds., St. Petersburg: Politekh. Univ., 2017, pp. 24–27.Google Scholar
- 4.Golubtsov, V.A., Dynin, A.Ya., Rogozhina, T.V., et al., Application of the NPP Company output at steel modification, Lit’e Metall., 2009, no. 3 (52), pp. 245–253.Google Scholar
- 5.Rybchikov, I.V., Akhmadeev, A.Yu., Rogozhina, T.V., et al., Comparative deoxidizing and modifying ability of magnesium and alkaline earth elements in the outof-furnace treatment of steel, Stal’, 2008, no. 12, pp. 51–54.Google Scholar
- 6.Soldatov, V.G. and Kul’bovskii, I.K., The use of modification to improve the performance properties of 20GL steel castings, Zagotovitel’nye Proizvod. Mashinostr., 2004, no. 4, pp. 5–7.Google Scholar
- 7.Andreev, I.D., Afonaskin, A.V., Bazhova, T.Yu., et al., Influence of technological parameters of modifying by complex modifiers on the properties of castings, Liteinoe Proizvod., 2002, no. 6, pp. 13–15.Google Scholar
- 8.Solntsev, Yu.P., Andreev, A.K., and Serditov, A.E., Khladostoikie i iznosostoikie liteinye stali (Cold and Wear Resistant Casted Steels), St. Petersburg: Khimizdat, 2007.Google Scholar
- 10.Andreev, A.K. and Solntsev, Yu.P., Increase of cold resistance of steel castings, Liteinoe Proizvod., 2008, no. 3, pp. 7–11.Google Scholar