Abstract
This study examines the impact of hot plastic deformation at 1250°C on austenite grain refinement and mechanical properties in carbon steel for railway wheels. The deformation strategies—single-step versus two-step compression with equivalent total strain—were compared to assess their effects on austenitic microstructure and material performance. Austenite grain size was quantified via light microscopy and quantitative structural analysis, while mechanical properties were evaluated using a universal tensile testing machine, following the ASTM E8 standard, at room temperature. (strain rate: 10⁻³ s⁻¹) Results reveal that austenite grain refinement occurs proportionally with increasing deformation, irrespective of the compression scheme. However, the deformation strategy significantly influences strength and ductility at lower strain levels. Specifically, two-stage compression at smaller strains (e.g., below 60% total deformation) enhances ultimate tensile strength by up to 10% and ductility by 30–40% compared to single-step compression. This improvement is attributed to partial retention of austenite substructure during interrupted deformation, which alters dynamic recrystallization kinetics and promotes dislocation redistribution. The differential effect diminishes progressively with higher strain levels, and beyond 60% deformation, both schemes yield equivalent grain sizes and mechanical properties due to complete recrystallization and microstructural homogenization. These findings underscore the critical role of deformation sequencing in optimizing mechanical performance during thermomechanical processing, particularly for applications requiring tailored strength-ductility balances in high-temperature-formed carbon steels.
References
- F. Haessner, Recrystallization of metallic materials, Dr.Riederer Verlag GmbH, Stuttgart, 1978.
- H. Gleiter, B. Chalmers, High-angle grain boundaries, Pergamon Press Oxford, 1972.
- A. Chamanfar, S.M. Chentouf, M. Jahazi, L.-P. Lapierre-Boire, Austenite grain growth and hot deformation behavior in a medium carbon low alloy steel, Journal of Materials Research and Technology, 9, (2020), 12102–12114.
- I. Vakulenko, S. Plitchenko, D. Bolotova, K. Asgarov, Influence hot plastic deformation on the structure and properties of carbon steel of the railway wheel, Zeszyty Naukowe. Transport/Politechnika Śląska, (2023).
- I.A. Vakulenko, L. Vakulenko, D. Bolotova, B. Kurt, H. Asgarov, Ö. Çölova, Influence structure on the plasticity of carbon steel of the railway wheel rim in operation, Zeszyty Naukowe. Transport/Politechnika Śląska, (2022) 183–192.
- A.F. Yilmaz, Assessment of Combinability of S235JR-S460MC Structural Steels on Fatigue Performance, Transactions of the Indian Institute of Metals 77, (2024), 323–331. https://doi.org/10.1007/s12666-023-03113-x.
- J.-W. Seo, H.-M. Hur, S.-J. Kwon, Effect of mechanical properties of rail and wheel on wear and rolling contact fatigue, Metals (Basel) 12, (2022), 630.
- A.I. Babachenko, Reliability and durability of railway wheels and tires, Dn-vsk: GVUZ" PGASA, (2015).
- R. Thackray, E.J. Palmiere, O. Khalid, Novel etching technique for delineation of prior-austenite grain boundaries in low, medium and high carbon steels, Materials 13, (2020), 3296.
- I.O. Vakulenko, Structural analysis in materials science, Makovetsky, Dnepropetrovsk, 2010.
- S. Gnapowski, M. Opiela, E. Kalinowska-Ozgowicz, J. Szulżyk-Cieplak, The Effects of Hot Deformation Parameters on the Size of Dynamically Recrystallized Austenite Grains of HSLA Steel, Advances in Science and Technology. Research Journal 14, (2020).
- Yu. Liang, S. Xiang, Y. Liang, M. Yang, Z. Wei, H. Xiong, J. Li, Effect of original oustenite grain size on the microstructure and toughness of pearlite steel , Materials Reports, 31, (2017), 77–81.
- F. Zhang, Y. Zhao, Y. Tan, X. Ji, S. Xiang, Study on the nucleation and growth of pearlite colony and impact toughness of eutectoid steel, Metals (Basel), 9, (2019), 1133.
- F.B. Pickering, B. Garbarz, The effect of transformation temperature and prior austenite grain size on the pearlite colony size in vanadium treated pearlitic steels, Scr. Metall.;(United States) 21 (1987).
- G.D. Sukhomlin, Specific Boundaries in Ferrite of Low-Carbon Steels, Metallofızıka I Noveıshıe Tekhnologıı 35 (2013) 1237–1249.
- D.L. Holt, Dislocation cell formation in metals, J Appl Phys 41 (1970) 3197–3201.
- R. Verner, Izmeljchenie zerna pri goryacheyj deformacii, in: Chernihe Metallih, 1969: pp. 34–43.
- I.G. Uzlov, O.N. Perkov, I.A. Vakulenko, Vliyanie skhemy goryachey deformatsii zagotovki na svoystva metalla oboda tselnokatanykh zheleznodorozhnykh koles, Fundamentalnye i Prikladnye Problemy Chernoy Metallurgii 5 (2002) 196–199.
Abstract
Bu çalışma, demiryolu tekerleklerinde kullanılan karbon çeliğinde 1250 °C’de uygulanan sıcak plastik deformasyonun, östenit tane incelmesi ve mekanik özellikler üzerindeki etkisini incelemektedir. Aynı toplam deformasyon oranına sahip tek aşamalı ve iki aşamalı sıkıştırma stratejileri, östenitik mikro yapı ve malzeme performansı üzerindeki etkilerini değerlendirmek amacıyla karşılaştırılmıştır. Östenit tane boyutu, ışık mikroskobu ve kantitatif yapısal analiz yöntemleri kullanılarak nicelendirildi; mekanik özellikler ise oda sıcaklığında (deformasyon hızı: 10⁻³ s⁻¹) gerçekleştirilen çekme testleriyle değerlendirildi. Elde edilen sonuçlar, sıkıştırma şemasından bağımsız olarak deformasyon arttıkça östenit tane incelmesinin orantılı olarak gerçekleştiğini göstermektedir. Bununla birlikte, deformasyon stratejisi daha düşük deformasyon seviyelerinde mukavemet ve süneklik üzerinde belirgin bir etki göstermektedir. Özellikle, toplam deformasyonun %60’ın altında kalan durumlarda uygulanan iki aşamalı sıkıştırma, tek aşamalı sıkıştırmaya kıyasla çekme mukavemetini %10’a kadar, sünekliği ise %30–40 oranında artırmaktadır. Bu iyileşme, kesintili deformasyon sırasında östenit alt yapısının kısmi korunmasına bağlı olup, bu durum dinamik yeniden kristalleşme kinetiğini değiştirerek dislokasyon yeniden dağılımını teşvik etmektedir. Deformasyon seviyesi arttıkça aradaki fark kademeli olarak azalmış ve %60’ın üzerindeki deformasyonlarda tam yeniden kristalleşme ve mikro yapısal homojenleşme neticesinde her iki sıkıştırma yöntemi de eşdeğer tane boyutları ve mekanik özellikler sergilemiştir. Bu bulgular, termomekanik işlem sırasında mekanik performansın optimize edilmesinde deformasyon sıralamasının kritik rolünü, özellikle yüksek sıcaklıkta şekillendirilen karbon çeliklerinde istenen mukavemet-süneklik dengesinin sağlanmasında vurgulamaktadır.
References
- F. Haessner, Recrystallization of metallic materials, Dr.Riederer Verlag GmbH, Stuttgart, 1978.
- H. Gleiter, B. Chalmers, High-angle grain boundaries, Pergamon Press Oxford, 1972.
- A. Chamanfar, S.M. Chentouf, M. Jahazi, L.-P. Lapierre-Boire, Austenite grain growth and hot deformation behavior in a medium carbon low alloy steel, Journal of Materials Research and Technology, 9, (2020), 12102–12114.
- I. Vakulenko, S. Plitchenko, D. Bolotova, K. Asgarov, Influence hot plastic deformation on the structure and properties of carbon steel of the railway wheel, Zeszyty Naukowe. Transport/Politechnika Śląska, (2023).
- I.A. Vakulenko, L. Vakulenko, D. Bolotova, B. Kurt, H. Asgarov, Ö. Çölova, Influence structure on the plasticity of carbon steel of the railway wheel rim in operation, Zeszyty Naukowe. Transport/Politechnika Śląska, (2022) 183–192.
- A.F. Yilmaz, Assessment of Combinability of S235JR-S460MC Structural Steels on Fatigue Performance, Transactions of the Indian Institute of Metals 77, (2024), 323–331. https://doi.org/10.1007/s12666-023-03113-x.
- J.-W. Seo, H.-M. Hur, S.-J. Kwon, Effect of mechanical properties of rail and wheel on wear and rolling contact fatigue, Metals (Basel) 12, (2022), 630.
- A.I. Babachenko, Reliability and durability of railway wheels and tires, Dn-vsk: GVUZ" PGASA, (2015).
- R. Thackray, E.J. Palmiere, O. Khalid, Novel etching technique for delineation of prior-austenite grain boundaries in low, medium and high carbon steels, Materials 13, (2020), 3296.
- I.O. Vakulenko, Structural analysis in materials science, Makovetsky, Dnepropetrovsk, 2010.
- S. Gnapowski, M. Opiela, E. Kalinowska-Ozgowicz, J. Szulżyk-Cieplak, The Effects of Hot Deformation Parameters on the Size of Dynamically Recrystallized Austenite Grains of HSLA Steel, Advances in Science and Technology. Research Journal 14, (2020).
- Yu. Liang, S. Xiang, Y. Liang, M. Yang, Z. Wei, H. Xiong, J. Li, Effect of original oustenite grain size on the microstructure and toughness of pearlite steel , Materials Reports, 31, (2017), 77–81.
- F. Zhang, Y. Zhao, Y. Tan, X. Ji, S. Xiang, Study on the nucleation and growth of pearlite colony and impact toughness of eutectoid steel, Metals (Basel), 9, (2019), 1133.
- F.B. Pickering, B. Garbarz, The effect of transformation temperature and prior austenite grain size on the pearlite colony size in vanadium treated pearlitic steels, Scr. Metall.;(United States) 21 (1987).
- G.D. Sukhomlin, Specific Boundaries in Ferrite of Low-Carbon Steels, Metallofızıka I Noveıshıe Tekhnologıı 35 (2013) 1237–1249.
- D.L. Holt, Dislocation cell formation in metals, J Appl Phys 41 (1970) 3197–3201.
- R. Verner, Izmeljchenie zerna pri goryacheyj deformacii, in: Chernihe Metallih, 1969: pp. 34–43.
- I.G. Uzlov, O.N. Perkov, I.A. Vakulenko, Vliyanie skhemy goryachey deformatsii zagotovki na svoystva metalla oboda tselnokatanykh zheleznodorozhnykh koles, Fundamentalnye i Prikladnye Problemy Chernoy Metallurgii 5 (2002) 196–199.
Details
| Primary Language | English |
|---|---|
| Subjects | Material Design and Behaviors |
| Journal Section | Research Articles |
| Authors | |
| Early Pub Date | April 30, 2025 |
| Publication Date | April 30, 2025 |
| Submission Date | February 6, 2025 |
| Acceptance Date | April 26, 2025 |
| Published in Issue | Year 2025 Volume: 6 Issue: 1 |
