Modeling of Microstructure Development in a Continuously Solidified Immiscible Alloy

Abstract:

A model is developed to analyze the microstructure evolution in a continuously solidified immiscible alloy. The model takes into account the common actions of the nucleation and the diffusional growth/shrinkage of the minority phase droplets, the spatial phase segregation and the convections of the melt. The microstructure formation in a continuously solidified immiscible alloy is calculated. The numerical results demonstrate that the convective flow has great effect on the microstructure evolution. The convective flow against the solidification direction causes an increase in the nucleation rate while the convective flow along the solidification direction causes a decrease in the nucleation rate of the minority phase droplets. The convective flow leads to a more nonuniform distribution of the minority phase droplets in the melt. It causes an increase in the size of the largest minority phase droplet and is against the obtaining of the immiscible alloys with a well dispersed microstructure.

• Periodical: Materials Science Forum (Volumes 654-656)
• Pages: 1536-1539
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.654-656.1536
• Online since: June 2010
• Authors: Jiu Zhou Zhao, Hai Li Li, Qing Liang Wang
• Keywords: Convection, Immiscible Alloy, Liquid-Liquid Phase Transformation, Micro-Structure Evolution, Modeling, Solidification

References

[1] J.Z. Zhao, H.L. Li and L. Zhao: Acta Metall. Sin. Vol. 45 (2009), p.1335.

[2] J.Z. Zhao and L. Ratke: Scr. Mater. Vol. 50 (2004), p.543.

[3] T. Carlberg and H. Fredriksson: Metall. Trans. A Vol. 11A (1980), p.1165.

[4] J.R. Rogers and R.H. Davis: Metall. Trans. A Vol. 21A (1990), p.59.

[5] R.H. Davis and M. A. Hassen: J. Fluid. Mech. Vol. 196 (1988), p.107.

[6] J.Z. Zhao, L. Ratke and B. Feuerbacher: Modelling Simul. Mater. Sci. Eng. Vol. 6 (1998), p.123.

[7] J.Z. Zhao. Scr. Mater. Vol. 54 (2006), p.247.

[8] J.J. Guo, Y. Liu, J. Jia, Y.Q. Su and H.S. Ding: Acta metal. Sin. Vol. 37 (2001), p.363.

[9] C.D. Cao and B.B. Wei. J: Mater. Sci. Technol. Vol. 18 (2002), p.73.

[10] M.H. Wu, A. Ludwig and L. Ratke: Metall. Mater. Trans. A Vol. 34A (2003), p.3009.

[11] H.L. Li, J.Z. Zhao and Q.X. Zhang: Metall. Mater. Trans. A Vol. 39A (2008), p.3308.