Metallurgical and Materials Transactions A

, Volume 36, Issue 12, pp 3281–3289 | Cite as

In-situ observations of lattice parameter fluctuations in austenite and transformation to bainite

  • S. S. Babu
  • E. D. Specht
  • S. A. David
  • E. Karapetrova
  • P. Zschack
  • M. Peet
  • H. K. D. H. Bhadeshia
Article

Abstract

The isothermal transformation of high-carbon austenite-to-bainitic ferrite has been investigated with the in-situ technique of time-resolved X-ray diffraction using synchrotron radiation. The measurements indicate that prior to transformation, the austenite divided into regions with significantly different lattice parameters. It is possible that this is due to the development of carbon-rich and carbon-poor regions in the austenite, as a precursor to transformations including the bainite reaction. The lattice parameter became uniform as transformation progressed and the fraction of carbon-poor austenite decreased. The ferrite itself exhibited a large range of lattice parameters during the early stages of transformation, due to the trapping of carbon.

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Copyright information

© ASM International & TMS-The Minerals, Metals and Materials Society 2005

Authors and Affiliations

  • S. S. Babu
    • 2
  • E. D. Specht
    • 1
  • S. A. David
    • 1
  • E. Karapetrova
    • 3
  • P. Zschack
    • 3
  • M. Peet
    • 4
  • H. K. D. H. Bhadeshia
    • 4
  1. 1.Metals and Ceramics DivisionOak Ridge National LaboratoryOak Ridge
  2. 2.the Edison Welding InstituteColumbus
  3. 3.the Frederick Seitz Materials Research LaboratoryUniversity of Illinois at Urbana-ChampaignUrbana
  4. 4.the Department of Materials Science and MetallurgyUniversity of CambridgeCambridgeUnited Kingdom

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