Continuous Cooling Transformation Behavior and the Phase Transformation Model in Low Carbon High Strength Sheet Steel

Abstract:

Phase transformation of austenite continuous cooling process in low carbon high strength sheet steel has been researched by DIL805 thermal mechanical simulate. The Austenite continuous cooling transformation (CCT) diagram of steel has been determined by dilatometry and metallography. With the increase of cooling rate, ferritic transformation, perlitic transformation, bainite transformation and martensitic transformation have produced in the organization. Mathematical equations of phase transformation point-cooling rate and phase variable-cooling rate have been established and phase transformation model of high fit degree has been gained by regression calculation. The results show that calculated value and experimental value are nearly similar, so the phase transformation model is feasible.

• Periodical: Advanced Materials Research (Volume 1035)
• Pages: 27-35
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1035.27
• Online since: October 2014
• Authors: Yu Pei*, Zhe Gao, Yi Liu, Shi Qian Zhao, Chang Yu Xu, Li Yong Ren, Xing Liang Li
• Keywords: CCT-Diagram, Cooling Rates, Low Carbon High Strength Sheet Steel, Phase Transformation Modeling

References

[1] Jun H J, Kang J S, Seo D H, et al. Effects of deformation and boron on microstructure and continuous cooling transformation in low carbon HSLA steels[J]. Materials Science and Engineering: A, 2006, 422(1–2): 157-162.

DOI: 10.1016/j.msea.2005.05.008

[2] Shanmugam S, Ramisetti N K, Misra R D K, et al. Effect of cooling rate on the microstructure and mechanical properties of Nb-microalloyed steels[J]. Materials Science and Engineering: A, 2007, 460–461: 335-343.

DOI: 10.1016/j.msea.2007.01.054

[3] ChengjiaShang, XueminWang, ShanwuYang, et al. Refinement of packet size in low carbon bainitic steel by special thermo-mechanical control process[J]. Journal of University of Science and Technology Beijing, 2004, 11(3): 221-224.

[4] Yakubtsov I A, Poruks P, Boyd J D. Microstructure and mechanical properties of bainitic low carbon high strength plate steels[J]. Materials Science and Engineering: A, 2008, 480(1–2): 109-116.

DOI: 10.1016/j.msea.2007.06.069

[5] Yuntang Z, Chengjia S, Shangwu Y, et al. Metastable austenite transformation in low carbon microalloying steel[J]. Journal of University of Science and Technology Beijing, 2007(7): 694-698.

[6] Kwon O. A technology for the prediction and control of microstructural changes and mechanical properties in steel[J]. ISIJ, 1992, 32(3): 350-356.

DOI: 10.2355/isijinternational.32.350

[7] George Krauss, Steven W Thompson. Ferritic microstructures in continuously cooled low-and ultralow-carbon steels[J]. ISIJ International, 1995, 35(8): 937-945.

DOI: 10.2355/isijinternational.35.937

[8] Guang X, Wei Z, Xinqiang Z, et al. The analysis and design the CCT diagrams of metal material[G]. Chemical Industry Press, (2009).

[9] Lijun W, Qingwu C, Wei Y, et al. Characterization and formation mechanism of microstructures of low carbon low alloy steel during continuous cooling transformation[J]. Journal of Materials Engineering, 2010(08): 29-33.

[10] Junhua K, Cangming L, Lin Z, et al. Continuous cooling transformation of ultra-low carbon microalloyed steel after deformation [J]. Heat Treatment of metals, 2004(11): 27-30.

[11] Gregg J M, Bhadeshia H K D H. Solid-state nucleation of acicular ferrite on minerals added to molten steel[J]. Acta Materialia, 1997, 45(2): 739-748.

DOI: 10.1016/s1359-6454(96)00187-5

[12] Ming F, Raojian Q, Qingfang X, et al. Fine dispersive carbide and tempered martensite embrittlement[J]. Journal of University of Science and Technology Beijing, 1989(01): 28-33.

[13] Manyun L, Benrong S. The technology of controlled rolling and controlled cooling process[G]. Metallurgical Industry Press, (1990).

[14] EB Hawbolt, B. Chau, JK Brimacombe. Kinetics of austenite-ferrite and austenite-pearlite transformation in a 1025 carbon steel[J]. Metall. Trans. A, 1985, 16 (4): 565.

DOI: 10.1007/bf02814230

[15] Zhuyao X. Martensite transformation and martensite[G]. Science Press, (1999).

[16] Dong X, Miaoyong Z, Zhengyou T, et al. The phase transformation model of SCM435 steel [J]. Journal of Harbin Engineering University, 2013(03): 394-397.