The relation between microstructure and mechanical properties of carbide-free bainitic steel 0.2% C – 1.53% Mn – 1.1% Si – 1% Cr – 0.3% Mo – 0.5% N under thermomechanical treatment is studied under isothermal conditions and under continuous air cooling. Impact tests of Charpy specimens, metallographic and x-ray diffraction analyses of the steel deformed by different variants are conducted. The size of the initial austenite grains and the Vickers hardness of the steel are determined. The hot plastic deformation is shown to affect positively the impact toughness of the steel treated for bainite.
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The authors acknowledge the Steel Technology Centre and the Central Research Facility of the Indian Institute of Technology in Kharagpur for providing the resources.
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Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 9 – 18, July, 2021.
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Hasan, S.M., Chakrabarti, D. & Singh, S.B. Thermomechanical Treatment of Carbide-Free Bainitic Steel. Met Sci Heat Treat 63, 354–362 (2021). https://doi.org/10.1007/s11041-021-00695-5
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DOI: https://doi.org/10.1007/s11041-021-00695-5