Mechanical Properties and Microstructure Comparative Analysis of 500MPa Hot Rolled H-Section Different Positions for Ultra-Deep well Platform

Abstract:

With the increase of drilling depth, the mechanical properties of H-section steel used in drilling platform are more and more demanding. In this paper, the strength, low temperature impact toughness, plasticity, micro-hardness and microstructure of 500MPa hot rolled H-section steel produced by TMCP process were analyzed, and the strengthening mechanism was also studied. The results show that flanges of TMCP hot rolled H-section steel had the best strength and toughness, while the yield strength at web and R Angle was reduced to 91% and 78% of the flange, respectively. The impact toughness at -40°C of web and R Angle was reduced to 86% and 38% of the flange , and the micro-hardness reduced to 91% and 85% of the flange, respectively. The main strengthening mechanism of the TMCP hot rolled H-section steel is fine-grain strengthening, the carbonitride of V precipitation strengthening and surface bainite transformation strengthening.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 464-472
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.464
• Online since: June 2021
• Authors: Cai Hong Lu*, Fang Po Li, Li Hong Han, Hui Zhang, Shang Yu Yang, Jian Jun Wang, Yao Rong Feng
• Keywords: 500MPa Hot-Roll H-Beam Steel, Different Position of H-Section, Mechanical Properties, Micro-Structure, Strengthening Mechanism

References

[1] Kimura T, Yamamoto K, Aoki H. Development of high strength H shapes with excellent toughness manufactured by advanced thermo-mechanical control process (TMCP)[J].JFE Technical Report, 2011, (16): 52-57.

[2] Xu Wenxi, Pan Hongbo, Men Jun, et al. Nb-V microalloying hot-rolled H-section TMCP process for polar offshore platforms[J]. Heat Treatment of Metals, 2016, 41(9): 89-93.

[3] Hao Yu, Hailong Zhou, Houxin Wang, et al. Strengthen-mechanism and corrosion resistance of niobium added HSLA weathering H-sections processed by ultra-fast cooling process[J]. HSLA Steels 2015, Microalloying 2015 & Offshore engineering Steels 2015 :1037-1044.

DOI: 10.1002/9781119223399.ch130

[4] Tarek Allam, Wolfgang Bleck. Development of a new concept for hot-rolled weathering-DP steel: Thermo-mechanical Simulation, microstructure Adjustment, andMechanical Properties [J]. Steel Research International, 2016, 87(1):68- 78.

DOI: 10.1002/srin.201500108

[5] Akihiko Kojima, Yoshiyuki Watanabe, Yoshio Tetada, et al. Ferrite grain refinement by large reduction per pass in non-recrystallization temperature region of Austenite[J]. ISI JInternational, 1996, 36(5): 603-610.

DOI: 10.2355/isijinternational.36.603

[6] Xing Jun, Wu Baoqiao, Cheng Ding, Pan Hongbo, Xu Wenxi, Xia Meng, VN microalloy hot-rolled H-section deformation austenite recrystallization law [J], Proceedings of the 11th China Iron and Steel Annual Conference, 2016, 1-5.

[7] Wang Zhuangfei, Shi Minghao, Chen Jun et al. Static recrystallization behavior of vanadium and ni-vanadium low-carbon microalloyed steels[[J]. Steel 2018, 53(04): 62-66.

[8] Hui Yajun, Pan Hui, Zhou Na, et al. Study on strengthening mechanism of 650MPa grade V-N microalloyed automobile beam steel fJl. Acta Metall Sinica. 2015, 51(12): 1481-1488.

[9] Qing Jiasheng, Shen Houfa, Liu Ming. High-strength weathering steel YQ4_SONQRI vanadium-nitrogen microalloying [[J]. Iron and Steel, 2017, 52(5): 87-93.

[10] Wang Youming, Li Manyun, Wei Guang. Controlled rolling and controlled cooling of steel "M]. Beijing, Metallurgical Industry Press, (1995).

[11] Cheng Ding, Xia Xun, Wu Baoqiao, etc. Low-temperature impact energy variation of thick-walled hot-rolled H-section steel along the width of the flange [J]. Journal of Anhui Vocational College of Metallurgy and Technology, 2017, 27(01):1-48.