Effect of Heat Treatment on the Microstructure and Hardness of Low-Alloy Carbon Steel Used in Structural Applications
DOI:
https://doi.org/10.47134/jme.v3i1.5364Keywords:
Heat Treatment, Low-Alloy Carbon Steel, Microstructure, Hardness, Structural ApplicationsAbstract
This research was conducted to evaluate the effects of various heat treatment methods on the microstructure and mechanical properties of low alloy carbon steel used in structural applications. The laboratory samples underwent a series of annealing, normalizing, quenching, and tempering processes, leading to the development of fine grains within specific temperatures of the austenitic range. The holding time for uniform temperature distribution was maintained by subsequent cooling rates through air, oil, and water quenching. An optical microscope showed substantial variations in the shapes of ferrite and pearlite, whereas a SEM could see the shape of martensite, depending on how it was treated. Mechanical tests, including the Vickers hardness test and the tensile strength test, were conducted to correlate the development or change in properties. The highest hardness is reported owing to the production of quenched samples, which is explained by tempering ductile materials to make them less brittle. Provided normalized showed balanced and appropriate for both needed use The research includes useful data that engineers may use to improve the performance of building materials that are exposed to changing load situations by changing the parameters of heat treatment. This, therefore, gives a good reason to choose the right way to heat treat low-alloy steels to get the needed mechanical qualities.
References
Badaruddin, M., Sugiyanto, S., Sumardi, S., & Asmi, D. (2024). Improvement of the fatigue crack growth resistance in AISI 4140 steel under single- and multi-austempering heat treatments. Results in Engineering, 17, Article 100986. https://doi.org/10.1016/j.rineng.2024.101814
Badri, M. A., Shenashen, A. M. A., & Abou-El-Hossein, M. H. (2021). Microstructure and mechanical properties of austempered AISI 4140 steel. Journal of Materials Processing Technology, 292, Article 117057. https://doi.org/10.1016/j.jmatprotec.2020.117057
Basori, I., Masitah, I., Susetyo, F. B., & Nanto, D. (2024). The effect of quenching process on the microstructure and hardness of AISI 4140 steel. Journal of Physics: Conference Series, 2866, Article 012020. https://doi.org/10.1088/1742-6596/2866/1/012020
Baxevanis, G., Siokos, F., Kaldellis, A., Ioannidou, D., Stergiou, V., Skarvelis, P., & Tsakiridis, P. E. (2024). Effect of post-weld heat treatment on hardness and corrosion resistance of dissimilar electron beam welded joints of Inconel 713LC and AISI 4140 steel. Journal of Materials Engineering and Performance, 33(1), 372–384. https://doi.org/10.1007/s11665-023-07968-5
Campos Becerra, L. H. (2025). A review of heat treatments applied to low-, medium-, and high-carbon steels used in cold drawing. Discover Materials, 5, Article 88. https://doi.org/10.1007/s43939-025-00261-3
Chen, H., Chen, T.-C., Hsu, H.-H., & Tsay, L.-W. (2025). Effect of microstructure and compressive residual stress on the fatigue performance of AISI 4140 steel with QPQ salt-bath nitrocarburizing. Materials, 18(9), Article 1995. https://doi.org/10.3390/ma18091995
Dhar, S. K., Gupta, J. S., & Prakash, G. (2022). Investigation in gas carburizing of AISI 4140, EN36, and 16MnCr5 steels using Taguchi–Grey relational method. Advances in Materials Science and Engineering, 2022, Article 6102139. https://doi.org/10.1155/2022/6102139
Jawale, J. A. (2020). Effect of deep cryogenic treatment on mechanical properties of AISI 4140 steel for jet engine components. Journal of Iron and Steel Research International, 27(3), 234–241. https://doi.org/10.1007/s42243-020-00123-4
Khan, T., Iqbal, M. Z., & Ahmad, M. (2020). Effect of different quenching media on microstructure and hardness of AISI 4130 steel. Materials Research Express, 7(2), Article 026516. https://doi.org/10.1088/2053-1591/ab678c
Kumar, A., & Kumar, V. (2022). Study of heat treatment on microstructure and hardness of AISI 1045 and AISI 4140 steel. Materials Today: Proceedings, 50, 2101–2105. https://doi.org/10.1016/j.matpr.2021.10.219
Laxmi, B., Sharma, S., J. P. K., & Hegde, A. (2022). Quenchant oil viscosity and tempering temperature effect on mechanical properties of 42CrMo4 steel. Journal of Materials Research and Technology, 16, 581–587. https://doi.org/10.1016/j.jmrt.2021.11.152
Mahmood, N. J., Hussein, A. A., Hasan, A. S., & Ali, O. M. (2022). Effect of AISI 4140 carbon steel heat treatments on specified mechanical properties. In AIP Conference Proceedings (Vol. 2660, Article 020065). https://doi.org/10.1063/5.0107707
Mudda, S., Hegde, A., Sharma, S., Gurumurthy, B. M., Shettar, M., & Gowrishankar, M. C. (2025). Effect of various heat treatment methods and optimization of their parameters on mechanical properties of AISI 4140 steel. Scientific Reports, 15, Article 31854. https://doi.org/10.1038/s41598-025-17299-1
Passanha, J., Sharma, S., Hegde, A., & Lakshmi, B. (2022). Experimental and statistical analysis of vegetable oil–brine egg yolk emulsion quench on the properties of AISI 4140 steel. Cogent Engineering, 9(1), 1–11. https://doi.org/10.1080/23311916.2022.2146626
Saber, M. A., Ahmadi, M. R., & Shojaei, A. (2020). Effect of annealing and normalizing on microstructure and mechanical properties of AISI 4140 steel. Journal of Materials Engineering and Performance, 29(5), 2904–2913. https://doi.org/10.1007/s11665-019-04567-8
Sharma, S., Shetty, A., & Gurumurthy, M. C. (2021). Quench hardening and mechanical characterization of AISI 4140 steel. Materials Today: Proceedings, 59, 127–132. https://doi.org/10.1016/j.matpr.2021.01.142
Singh, G. K., Harsha, S. S., & Murty, R. (2022). Effect of sub-zero and cryogenic treatments on microstructure and properties of alloy steels. Materials Science and Engineering A, 558, 610–616. https://doi.org/10.1016/j.msea.2022.09.078
Singh, R. S., Venkatesh, N. V., & Mahapatra, R. N. (2020). Effect of heat treatment on structure and properties of additively manufactured AISI 4140 steel. Additive Manufacturing, 31, Article 100979. https://doi.org/10.1016/j.addma.2019.100979
Tajmiri, S., Haider, W., & Shabib, I. (2024). Effect of heating rate on microstructure and corrosion resistance of quenched and tempered 8620 low carbon alloy steel. Corrosion and Materials Degradation, 5(3), 370–386. https://doi.org/10.3390/cmd5030016
Yalçın, E. D. (2025). Tribological performance of AISI 4140 steel quenching hardened with NaOH solution and coated with AlTiCrN by PVD method. Results in Physics, 77, Article 108466. https://doi.org/10.1016/j.rinp.2025.108466
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