# Influences of Initial Composition and Solid Back Diffusion on the Solidification Path of Al–Fe–Si Alloys

## Abstract

The influence of initial composition and the united solid back diffusion (SBD) effects on the calculated solidification paths (SP) of a series Al*–*Fe–Si ternary eutectic alloy were analyzed. The calculation programme was coupled with Thermo-Calc to calculate equilibrium for phase diagram information. The calculated results showed that initial compositions and SBD coefficient had important effects on SP of the Al*–*Fe–Si ternary eutectic alloys. The SP of the five Al*–*Fe–Si ternary alloys were divided into three categories: \( L \to (L + \beta ) \to (L + \alpha + \beta ) \to (L + \alpha + \beta + \text{Si}) \), \( L \to (L + \alpha ) \to (L + \alpha + \beta ) \to (L + \alpha + \beta + \text{Si}) \), and \( L \to (L + \alpha ) \to (L + \alpha + \text{Si}) \to (L + \alpha + \beta + \text{Si}) \). It was found that the volume fraction of eutectic phase decreases obviously with the increase of the SBD coefficient. Solute distribution coefficients of *K*_{Fe} and *K*_{Si} in Al–0.08Fe–4.8Si alloy were also calculated and analyzed.

## Keywords

Al–Fe–Si Solid back diffusion Solidification path## Notes

### Acknowledgements

We thank a lot for the financial support from the National Natural Science Foundation of China (Grant Nos. 51604162 and 51604161). We wish to thank Harbin Institute of Technology for providing the phase diagram information and data used in this paper. And we thank the opening fund of Hubei Key Laboratory of Hydroelectric Machinery Design & Maintenance (2017KJX12).

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