A Kinetic Model for Ferrite-Austenite Transformation

doi:10.12068/j.issn.1005-3026.2023.07.004

Abstract

Abstract: In this paper，based on the concepts of mixed model and Gibbs energy balance model， a simple Gibbs energy balance model was established to simulate the ferrite-austenite transformation of Fe-C-Mn low carbon steel during the intercritical annealing at 780℃. The effects of Gibbs free energy， effective grain size and alloying distribution on the transformation were studied. The results show that the initial effective grain size and interfacial mobility greatly affected the kinetics of phase transformation， while they had little effect on the final volume fraction of the austenite. The dissipation energy caused by the Mn enrichment at the interface during phase transformation slowed down the transformation kinetics and reduced the final volume fraction of the austenite. It is found that the modelling results above are in good accordance with the experimental ones.

Key words: phase transformation kinetics； Gibbs energy balance； ferrite-austenite transformation； solute drag effect

CLC Number:

TG111.5

LAN Hui-fang， LIU Ze-yang， WU Meng-ru. A Kinetic Model for Ferrite-Austenite Transformation[J]. Journal of Northeastern University(Natural Science), 2023, 44(7): 938-943.

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