Advertisement

In-Situ X-Ray Diffraction Measurement During Deformation of Austenite Above the Ae3 Temperature

  • Clodualdo AranasJr.Email author
  • Samuel Rodrigues
  • Fulvio Siciliano
  • John J. Jonas
Conference paper
  • 415 Downloads
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

Austenite has been shown to dynamically transform into ferrite during thermomechanical processing. The driving force is the softening that takes place during deformation, while the energy obstacles consist of the free energy difference between austenite and ferrite as well as the shear dilatation and shear accommodation work. Phase transformation can only take place once the driving force is greater than the energy obstacles. In this work, volume fractions of dynamically transformed ferrite from various rolling simulations were presented. The dynamic phase change was verified by performing hot compression experiment using a modified Gleeble system equipped with a synchrotron light X-ray diffraction. The X-ray diffraction measurements were carried out before and during deformation to accurately track the behavior of austenite. The results indicate that austenite indeed transforms dynamically into ferrite. This unusual metallurgical phenomenon is known to generate ultrafine grain microstructure, which translates to improved mechanical properties of steels.

Keywords

Steel Dynamic transformation In-situ XRD DT ferrite Thermomechanical processing 

Notes

Acknowledgements

The authors thank the National Synchrotron Light Laboratory (LNLS) in Campinas, Brazil, for the access to their facilities for the XRD experiment. The authors also acknowledge with gratitude funding received from the Brazilian National Council for Scientific and Technological Development (CNPq), Research and Support Foundation of Maranhão (FAPEMA), Natural Sciences and Engineering Research Council of Canada (NSERC), New Brunswick Innovation Foundation (NBIF), and Harrison McCain Foundation.

References

  1. 1.
    Ghosh C, Aranas C, Jonas JJ (2016) Dynamic transformation of deformed austenite at temperatures above the Ae3. Prog Mater Sci 82:151–233CrossRefGoogle Scholar
  2. 2.
    Beladi H, Kelly GL, Hodgson PD (2007) Ultrafine grained structure formation in steels using dynamic strain induced transformation processing. Int Mater Rev 52:14–28CrossRefGoogle Scholar
  3. 3.
    Park N, Shibata A, Terada D, Tsuji N (2013) Flow stress analysis for determining the critical condition of dynamic ferrite transformation in 6Ni-0.1C steel. Acta Mater 61:163–173CrossRefGoogle Scholar
  4. 4.
    Chen SC, Huang CY, Wang YT, Yen HW (2017) Mater Des 134(2017):434CrossRefGoogle Scholar
  5. 5.
    Pereloma E, Timokhina I (2018) Deformation-induced phase transformation. Metals 8(11):886CrossRefGoogle Scholar
  6. 6.
    Li CM, Yada H, Yamagata H (1998) A novel observation of strain-induced ferrite-to-austenite retransformation after intercritical deformation of C–Mn steel. Scr Mater 39:963–967CrossRefGoogle Scholar
  7. 7.
    Jonas JJ, Aranas C, Basabe VV, Ghosh C (2014) Dynamic transformation during the torsion simulation of strip rolling. Mater Sci Forum 783:39–44CrossRefGoogle Scholar
  8. 8.
    Basabe VV, Jonas JJ, Ghosh C (2014) Formation of Widmanstätten ferrite in a 0.036% Nb low carbon steel at temperatures above the Ae3. Steel Res Int 85(1):8–15Google Scholar
  9. 9.
    Aranas C, Jonas JJ (2015) Effect of Mn and Si on the dynamic transformation of austenite above the Ae3 temperature. Acta Mater 82:1–10CrossRefGoogle Scholar
  10. 10.
    Aranas C, Wang T, Jonas JJ (2015) Effect of interpass time on the dynamic transformation of a plain C–Mn and Nb microalloyed steel. ISIJ Int 55(3):647–654CrossRefGoogle Scholar
  11. 11.
    Aranas C, Rodrigues SF, Grewal R, Jonas JJ (2015) Ferrite formation above the Ae3 temperature during the torsion simulation of strip rolling. ISIJ Int 55(11):2426–2434CrossRefGoogle Scholar
  12. 12.
    Zhao L, Park N, Tian Y, Shibata A, Tsuji N (2016) Combination of dynamic transformation and dynamic recrystallization for realizing ultrafine-grained steels with superior mechanical properties. Sci Rep 6:39127CrossRefGoogle Scholar
  13. 13.
    Rodrigues SF, Aranas C, Wang T, Jonas JJ (2017) Dynamic transformation of an X70 steel under plate rolling conditions. ISIJ Int 57(10):162–169CrossRefGoogle Scholar
  14. 14.
    Rodrigues SF, Aranas C, Jonas JJ (2017) Retransformation behavior of dynamically transformed ferrite during the simulated plate rolling of a low C and an X70 Nb steel. ISIJ Int 57(5):929–936CrossRefGoogle Scholar
  15. 15.
    Aranas C, Rodrigues SF, Siciliano F, Jonas JJ (2019) In-situ X-ray diffraction evidence of dynamic transformation of austenite to ferrite during hot compression test in the single austenite phase field. Scripta Mater. submittedGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society 2020

Authors and Affiliations

  • Clodualdo AranasJr.
    • 1
    Email author
  • Samuel Rodrigues
    • 2
  • Fulvio Siciliano
    • 3
  • John J. Jonas
    • 4
  1. 1.Mechanical EngineeringUniversity of New BrunswickFrederictonCanada
  2. 2.Department of Materials EngineeringFederal Institute of MaranhaoSao LuisBrazil
  3. 3.Dynamic Systems IncPoestenkillUSA
  4. 4.Materials EngineeringMcGill UniversityMontrealCanada

Personalised recommendations