Effect of Different Thermomechanical Processes on the Microstructure, Texture, and Mechanical Properties of API 5L X70 Steel

  • Mohammad Masoumi
  • Edwan Anderson Ariza Echeverri
  • Cleiton Carvalho Silva
  • Miloslav Béreš
  • Hamilton Ferreira Gomes de Abreu


A commercial API 5L X70 steel plate was subjected to different thermomechanical processes to propose a novel thermomechanical rolling path to achieve improved mechanical properties. Scanning electron microscopy, electron backscatter diffraction, and x-ray texture analysis were employed for microstructural characterization. The results showed that strain-free recrystallized {001} ferrite grains that developed at higher rolling temperature could not meet the American Petroleum Institute (API) requirements. Also, refined and work-hardened grains that have formed in the intercritical region with high stored energy do not provide suitable tensile properties. However, fine martensite–austenite constituents dispersed in ferrite matrix with grains having predominantly {111} and {110} orientations parallel to the normal direction that developed under isothermal rolling at 850 °C provided an outstanding combination of tensile strength and ductility.


API 5L X70 steel crystallographic texture thermomechanical processes 



The authors acknowledge the CAPES and CNPq Brazilian research agencies for financial support and Central Analítica-UFC/CT-INFRA/MCTI-SISNANO/Pró-Equipamentos for providing research facilities used in this work.


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Copyright information

© ASM International 2018

Authors and Affiliations

  • Mohammad Masoumi
    • 1
    • 2
  • Edwan Anderson Ariza Echeverri
    • 1
  • Cleiton Carvalho Silva
    • 2
  • Miloslav Béreš
    • 2
  • Hamilton Ferreira Gomes de Abreu
    • 2
  1. 1.Department of Metallurgical and Materials EngineeringUniversity of São PauloSão PauloBrazil
  2. 2.Department of Metallurgical and Materials EngineeringFederal University of CearáFortalezaBrazil

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