Influence of specimen geometry of hot torsion test on temperature distribution during reheating treatment of API-X70

  • Bahman MirzakhaniEmail author
  • Shahin Khoddam
  • Hossein Arabi
  • Mohammad Taghi Salehi
  • Seyed Hossein Seyedein
  • Mohammad Reza Aboutalebi


The commercial finite element package ANSYSTM was utilized for prediction of temperature distribution during reheating treatment of hot torsion test (HTT) samples with different geometries for API-X70 microalloyed steel. Simulation results show that an inappropriate choice of test specimen geometry and reheating conditions before deformation could lead to non-uniform temperature distribution within the gauge section of specimen. Therefore, assumptions of isothermal experimental conditions and zero temperature gradient within the specimen cross section appear unjustified and led to uncertainties of flow curve obtained. Recommendations on finding proper specimen geometry for reducing temperature gradient along the gauge part of specimen will be given to create homogeneous initial microstructure as much as possible before deformation in order to avoid uncertainty in consequent results of HTT.

Key words

hot torsion test simulation specimen geometry reheating treatment microalloyed steel 


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Copyright information

© China Iron and Steel Research Institute Group 2010

Authors and Affiliations

  • Bahman Mirzakhani
    • 1
    Email author
  • Shahin Khoddam
    • 2
  • Hossein Arabi
    • 3
  • Mohammad Taghi Salehi
    • 3
  • Seyed Hossein Seyedein
    • 3
  • Mohammad Reza Aboutalebi
    • 3
  1. 1.Faculty of EngineeringArak UniversityArakIran
  2. 2.Department of Mechanical EngineeringMonash UniversityVicAustralia
  3. 3.Department of Materials and Metallurgical EngineeringIran University of Science and TechnologyTehranIran

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