Mathematical model of microstructure evolution of X60 line pipe steel during CSP hot rolling

  • Quan LiEmail author
  • Zheng-dong Liu
  • Guang-bo Tang
  • Zhi-ling Tian
  • Fulio Siciliano


An integrated process modelling system for simulating the microstructure evolution of Nb-microalloyed HSLA steel produced in CSP hot rolling process has been developed on the basis of the microstructure simulation and mechanical properties prediction technology. 3-D thermomechanical coupled finite element models for simulating hot strip rolling have been developed and the distribution of equivalent plastic strain through the thickness direction of the rolled material by CSP rolling was obtained. Thus the distribution of temperature, strain and strain rate through the thickness of the steel stocks, as well as the microstructure evolution during hot rolling of X60 line pipe steel strip has been investigated by using the developed integrated process modelling system. In addition, the determination and optimization of controllable process parameters during CSP hot strip rolling for the Nb-microalloyed X60 line pipe steel have been implemented, and control strategies such as adopting larger pass reduction in the first stand, arranging appropriate pass interval times and proper rolling speed, to reduce or eliminate mixed grain microstructure of Nb micro-alloyed strip in CSP processing have been proposed.

Key words

CSP line pipe steel niobium microalloying microstructure evolution mathematical modelling 


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Copyright information

© China Iron and Steel Research Institute Group 2010

Authors and Affiliations

  • Quan Li
    • 1
    Email author
  • Zheng-dong Liu
    • 1
  • Guang-bo Tang
    • 1
  • Zhi-ling Tian
    • 1
  • Fulio Siciliano
    • 2
  1. 1.Institute for Structural MaterialsCentral Iron and Steel Research InstituteBeijingChina
  2. 2.Company Brazil Metallurgy and MineralSao PauloBrazil

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