Application of the stagnant stage concept for monitoring Mn partitioning at the austenite-ferrite interface in the intercritical region for Fe–Mn–C alloys

Abstract

The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning.

Keywords:

• interface
• diffusion
• kinetics
• dilatometry
• phase transformations

Acknowledgments

The authors acknowledge Dr Dave Hanlon for providing the materials, and Arcelor Mittal for financial support. The authors acknowledge Mr Nico Geerlofs for assistance in the dilatometer experiments.