Effect of Ferrite Volume Fraction on Mechanical Properties of X80 Pipeline Steel

Abstract:

The effect of volume fraction of ferrite on the mechanical properties including strength, plasticity and wok hardening was systematically investigated in X80 pipeline steel in order to improve the plasticity. The microstructures with different volume fraction of ferrite and bainite were obtained by heat-treatment processing and the mechanical properties were tested. The work hardening behavior was analyzed by C-J method. The results show that the small amount of ferrite could effectively improve the plasticity. The work hardening ability and the ratio of yield/tensile strength with two phases of ferrite/bainite would be obviously better than that with single phase of bainite. The improvement of plasticity could be attributed to the ferrite in which more plastic deformation was afforded.

• Periodical: Advanced Materials Research (Volumes 989-994)
• Pages: 212-215
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.989-994.212
• Online since: July 2014
• Authors: J. Liu*, G. Zhu, W. Mao
• Keywords: Bainite/Ferrite Two Phases, Plasticity, Strain Distribution, Work Hardening, X80 Pipeline Steel

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