Journal of Materials Engineering and Performance

, Volume 28, Issue 1, pp 107–116 | Cite as

Microstructure Evolution and Mechanical Property of Low-Alloy Steel Used for Armor Layer of Flexible Pipe During Thermomechanical Process and Hot Rolling Process

  • Zhenguang LiuEmail author
  • Shoudong Chen
  • Xiuhua Gao
  • Guanqiao Su
  • Linxiu Du
  • Jianping Li
  • Xiaonan Wang
  • Xiaowei Zhou


In this paper, the thermomechanical process and hot rolling process were carried out to study the microstructure evolution and mechanical property of low-alloy steel used for armor layer of flexible pipes by analyzing continuous cooling transformation curve, microstructure morphology, grain characteristics, and strength. The experimental results indicate that deformation process promotes phase transformation process of both ferrite and bainite and induces the formation of fine grain. The density of low-angle grain boundary rises with increasing cooling rate. The dislocation concentration in grain becomes larger with the extended cooling rate. The microstructure of hot-rolled specimen consists of polygonal ferrite and granular bainite, which is consistent with one of the deformed specimens with similar cooling rate in dilatometer. The microstructure evolution provides effective data fundament for hot rolling process.


flexible pipe low-alloy steel microstructure 



The authors are grateful for financial support from Doctoral Scientific Research Foundation of Jiangsu University of Science and Technology (1062931702), National High Technology Research and Development Program of China (2015AA03A501), Natural Science Foundation of China (NSFC, 51305285, 51605203), and Natural Science Foundation of Jiangsu Province (BK20180984).


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Copyright information

© ASM International 2018

Authors and Affiliations

  • Zhenguang Liu
    • 1
    Email author
  • Shoudong Chen
    • 2
  • Xiuhua Gao
    • 3
  • Guanqiao Su
    • 3
  • Linxiu Du
    • 3
  • Jianping Li
    • 3
  • Xiaonan Wang
    • 4
  • Xiaowei Zhou
    • 1
  1. 1.School of Material Science and Engineering and National Demonstration Center for Experimental Materials Science and Engineering EducationJiangsu University of Science and TechnologyZhenjiangChina
  2. 2.School of Mechanical EngineeringTongling UniversityTonglingChina
  3. 3.State Key Laboratory of Rolling and AutomationNortheastern UniversityShenyangChina
  4. 4.Shagang School of Iron and SteelSoochow UniversitySuzhouChina

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