Thermodynamic re-assessment of the Fe-Al-C system based on the Fe-rich experimental data

Abstract

The influence of C and Al content on phase transformation temperatures, i.e., the A₁ and A₃ of Fe-rich alloys is investigated by dilatometric analysis. With the new set of experimental data, an updated thermodynamic description of the Fe-Al-C system is presented, by using the thermodynamic data of the Fe-C, Fe-Al and Al-C systems, as well as the parameters for the Fe-Al-C ternary system optimized in this study. The good compatibility of the thermodynamic parameters with experimental data is demonstrated by several calculated vertical sections. A well reproduced vertical section of the Fe-Mn-Si-Al-C system is also presented according to the thermodynamic description of the lower order systems.

Keywords

iron-aluminum-carbon / TRIP steel / phase diagram / thermal analysis

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Acknowledgements

This work was financially supported by the National Natural Science Foundation of China under Grant No. 50671061 and Baosteel Company Grant R06DSEB020.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg