Prediction Model for Microstructure and Properties of Medium Carbon Non-Quenched and Tempered Steel Bar

Abstract:

In this study, the 38MnSiVS medium carbon non-quenched and tempered steel bar was investigated by optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM) and quantitative metallography. The microstructures were mainly composed of ferrite and pearlite. The phase transition-microstructure prediction models were established to calculate ferrite volume fraction f_α, ferrite grain size d_α and pearlite interlamellar spacing S_o. The volume fraction of the second phase V (C, N) was calculated by thermodynamics. The morphology of the second phase V (C, N) was observed by TEM, and the distribution of particle size of the second phase was determined. And the mechanical properties were measured. Considering the microstructural parameters (f_α,d_α and S_o), the modified coefficient of solid solution elements, and the effect of precipitates, combining with some reference models, prediction model of mechanical properties including yield strength, tensile strength and impact toughness were finally established.

• Periodical: Materials Science Forum (Volume 993)
• Pages: 526-533
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.526
• Online since: May 2020
• Authors: Shi Kang Lu*, Yu Lai Chen, Wei Yu
• Keywords: Medium Carbon Non-Quenched Steel, Precipitation Strengthening, Second Phase, Structure-Property Prediction Model, Tempered Steel

References

[1] Marina Odnobokova, Andrey Belyakov, Rustam Kaibyshev. Grain refinement and strengthening of austenitic stainless steels during large strain cold rolling,J. Philosophical Magazine. 99(2019).

DOI: 10.1080/14786435.2018.1546961

[2] Jongun Moon, Min Ji Jang, Jae Wung Bae, DamiYim, Jeong Min Park, Jehyun Lee, Hyoung Seop Kim. Mechanical behavior and solid solution strengthening model for face-centered cubic single crystalline and polycrystalline high-entropy alloys, J. Intermetallics.98 (2018).

DOI: 10.1016/j.intermet.2018.04.022

[3] Sych O V, Kruglova A A, Schastlivtsev V M, et al. Effect of vanadium on the precipitation strengthening upon tempering of a high-strength pipe steel with different initial structure, J. The Physics of Metals and Metallography.117 (2016)1270-1280.

DOI: 10.1134/s0031918x16120152

[4] Di Wu, XianmingZhao,Chunyu He. Study on prediction model of rolling structure and properties of high carbon steel high speed wire rod, J. Iron and Steel.(2003) 43-46.

[5] Pinguan Wei, Sijie Xiang, Bin Shen, HenghuaZhang. Rolling process simulation and microstructure and properties prediction of ship plate steel, J.Shanghai Metal. 36(2014) 54-58.

[6] Guoming Zhu. Prediction and Simulation of Microstructure-property and Residual Stress for Large Size Hot Rolled H-Beam, A.Chinese Society for Materials Research. 10(2012).

[7] Qilong Yong. Second Phase in Steel Materials, Metallurgical Industry Press, Beijing,(2006).

[8] Gladman T. The Physical Metallurgy of Microalloyed Steels, The Institute of Materials London, (1997).

[9] Jun Peng. Prediction of mechanical properties of medium carbon ferrite-pearlite non-quenched and tempered steel, PhD thesis, Yunnan University, Yunnan, (2011).

[10] Chengrui Dong. Microalloyed non-tempered steel, Metallurgical Industry Press, Beijing, 2000. (in Chinese).

[11] Gladman, Terry. Structure-property relationships in high-strength micro-alloyed steel, Proc. of Symp. on Microalloying 75. Union Carbide Corp, (1976).