Effect of Strain Rate on the Hot Ductility Behaviorof a Continuously Cast Ti–Nb Microalloyed Steel

Marina Melo Gontijo, Christian Hoflehner, Paul Estermann, Sergiu Ilie, Jakob Six, Christof Sommitsch*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

During the continuous casting process, alloys may be more susceptible to crack initiation under some conditions due to lower ductility. A Ti–Nb microalloyed steel is subjected to in situ melted hot tensile tests to evaluate its hot ductility behavior. The ductility is examined at different strain rates and temperatures. The samples are heated with an induction coil to the melting temperature in a vacuum atmosphere. Afterward, they are cooled to the desired test temperatures. Hot tensile tests are conducted by a thermomechanical simulator with strain rates varying from 10 −5 to 10 −2 s −1. The results show a ductility minimum around 800 °C for the standard strain rate of 10 −3 s −1 and a significant influence of the changes in strain rate in the behavior of the alloy for all the tested temperatures. The fracture surfaces are compared for 700, 800, and 900 °C at 10 −4, 10 −3, and 10 −2 s −1, as well as the microstructure. Computer simulations are done for the determination of the transformation temperatures, Scheil–Gulliver solidification simulation, and analysis of the precipitation kinetics during the tests. The results from simulations are discussed in comparison with the ones seen experimentally.

Original languageEnglish
Article number2000222
Number of pages10
JournalSteel Research International
Volume91
Issue number12
Early online date10 Jul 2020
DOIs
Publication statusPublished - Dec 2020

Keywords

  • continuous casting
  • hot ductility
  • low alloyed
  • steels
  • strain rate

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Metals and Alloys
  • Materials Chemistry
  • Physical and Theoretical Chemistry

Fields of Expertise

  • Advanced Materials Science

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