Effect of Composition System on Microstructure and Properties of 1000-MPa Grade Cold Rolled DPSteel

Abstract:

1000 MPa grade cold-rolled duplex steel with 5 component systems was trial-produced in the laboratory. After hot rolling, pickling and cold rolling, the test steel was simulated continuous annealing on Gleeble-3800 thermal simulator. The microstructure and properties of 5 kinds of experimental steels after simulated annealing were analyzed. The results show that C and Mn elements are the basic alloy systems of all duplex steels. In the case of low Si element, the C element content of the 1000 MPa grade dual phase steel should be 0.15 % or higher, and the Mn element content should be higher than 1.8 %. Si element increased to the A3 point, while the amount of austenite was less in the two-phase region during annealing, and the volume fractionof martensiteafter the rapid cooling is insufficient; Nb element is a high-efficiency fine-grain strengthening element, which greatly improvedthe uniformity of the steel species. The fine-grained martensite islands have enhance the tempering stability of martensite and thereby to reduce the adverse strength effect from over-aging temperature.

• Periodical: Materials Science Forum (Volume 993)
• Pages: 534-540
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.534
• Online since: May 2020
• Authors: Xiao Long Zhao*, Dong Liang Zhao
• Keywords: Cold Rolled DPSteel, Component, Microstructure, Performance

References

[1] Turiel E. The Development of Morality[J]. Transactions of Materials & Heat Treatment, 2006, 32(2):43-47.

[2] Ma J.Y, Deng Z.J, Hu K.H, et al. Effects of organization on the properties of cold rolled duplex steels[J]. China Materials Science and Technology, 2014(5): 51-53.

[3] Liu X.D. Research and development of cold rolled dual phase steel DP590 and DP780 for automobile [D]. Liaoning University of Science and Technology, (2016).

[4] Zuo X.R, Chen Y.B, Wang Y.H, et al. Microstructure and properties of ferrite/martensitic duplex steel[J]. Journal of Materials Heat Treatment, 2010, 31(1): 29-34.

[5] Zhan H, Zheng X.F, Cui L, et al. Study on microstructure and properties of 600MPa grade cold-rolled dual-phase steel under different cooling rates [C]// China Automotive Engineering Society Annual Meeting. (2015).

[6] Cheng J Y, Chen Y L, Zhao A M, et al. Microstructure and mechanical properties of 30SiMnCrB5 hot stamping steel[J]. Journal of University of Science & Technology Beijing, 2014, 36(10):1299-1306.

[7] Chen T, Zhao A M, Fan H L, et al. Hardenability and quenched microstructure of wear resistant steel 65MnCr with thick section[J]. Transactions of Materials & Heat Treatment, 2016, 37(11):129-134.

[8] Ogawa T. Ferrite recrystallization and austenite formation at the early stage of annealing in cold-rolled low-carbon steels[J]. International Journal of Mechanical & Materials Engineering, 2015, 10(1):22.

DOI: 10.1186/s40712-015-0049-4

[9] Mazaheri Y, Kermanpur A, Najafizadeh A, et al. Kinetics of Ferrite Recrystallization and Austenite Formation During IntercriticalAnnealing of the Cold-Rolled Ferrite/MartensiteDuplex Structures[J]. Metallurgical & Materials Transactions A, 2016, 47(3):1040-1051.

DOI: 10.1007/s11661-015-3288-3

[10] Burrows K. The effects of acrylic acid on the electro-mechanical behaviour of ITO-coated polymer substrates for flexible display technologies. (2013).

[11] Tovpenets Y S, Ivanov F I, Gontar M A. The effects of cooling techniques on the quantity of residual austenite during the forging of steel. Metal Science & Heat Treatment of Metals, 1962, 4(5-6):183-187.

DOI: 10.1007/bf00819261