|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Microstructural Modeling and Thermodynamics-kinetics Relations of the Austenite-to-ferrite Transformation in Fe-C-Mn-Si Steels
||Shaojie Song, Wenkan Che, Feng Liu
|On-Site Speaker (Planned)
During the multi-stage processing of advanced high-strength steels, the austenite-to-ferrite transformation, generally as a precursor of the formation of other non-equilibrium or metastable structures, can have a severe effect on the subsequent phase transformations. Herein, a more flexible microstructural predictive modeling for the key austenite-to-ferrite transformation of Fe-C-Mn-Si steels was developed, in combination with the classical nucleation theory, the general mixed-mode growth model from Gibbs energy balance, the microstructural path method and the kinetics framework for grain boundary nucleation. This model can output ferrite volume fraction, austenite/ferrite interface area per unit volume, and ferrite average grain size, which will serve as the input parameters for modeling the subsequent bainite or martensite transformations. Model application to the experimental measurements of Fe-0.17C-0.91Mn-1.03Si (wt.%) steels at different temperatures demonstrates its good effectiveness. At last, the relationship of the interface migration chemical driving force and the corresponding kinetics barrier was illustrated.
||Planned: Supplemental Proceedings volume