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Modifying agent selection for Al-7Si alloy by Miedema model

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Abstract

To determine the modifying agents for Al-7Si alloys, microstructure observation and mixing enthalpy analysis using Miedema model for Al-7Si alloy with additions of different rare earth elements were performed, and the effects of rare earth elements on the modification of eutectic silicon morphology were investigated. The results of mixing enthalpy analysis show that these four rare earth elements, La, Sm, Pr, and Ce, which have the large negative mixing enthalpies with Si, can be selected as modifying agents for eutectic silicon morphology. The element with the largest negative mixing enthalpy is Ce. Furthermore, the microstructures indicate that these four elements can effectively modify the eutectic (α)Al-Si crystals in Al-7Si alloy, and the most effective one is also Ce. Differential scanning calorimetry (DSC) results show that the eutectic temperature depressions due to the additions of modifying agents are the important reasons for the modification of eutectic (α)Al-Si crystals.

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References

  1. Y.C. Tsai, C.Y. Chou, S.L. Lee, et al., Effect of trace La addition on the microstructures and mechanical properties of A356 (Al-7Si-0.35Mg) aluminum alloys, J. Alloys Compd., 487(2009), No.1–2, p.157.

    Article  Google Scholar 

  2. C.Y. Chou, S.L. Lee, and J.C. Lin, Effects and deformation characteristics of cross-channel extrusion process on pure Sn and Al-7Si-0.3Mg alloy, Mater. Chem. Phys., 107(2008), No.2–3, p.193.

    Article  Google Scholar 

  3. K. Nogita and A.K. Dahle, Effects of boron on eutectic modification of hypoeutectic Al-Si alloys, Scripta Mater., 48(2003), No.3, p.307.

    Article  Google Scholar 

  4. Y.C. Lee, A.K. Dahle, D.H. StJohn, and J.E.C. Hutt, The effect of grain refinement and silicon content on grain formation in hypoeutectic Al-Si alloys, Mater. Sci. Eng. A, 259(1999), No.1, p.43.

    Article  Google Scholar 

  5. A.K. Dahle, K. Nogita, S.D. McDonald, et al., Eutectic modification and microstructure development in Al-Si alloys, Mater. Sci. Eng. A, 413–414(2005), p.243.

    Article  Google Scholar 

  6. A. Knuutinen, K. Nogita, S.D. McDonald, and A.K. Dahle, Modification of Al-Si alloys with Ba, Ca, Y and Yb, J. Light Met., 1(2001), No.4, p.229.

    Article  Google Scholar 

  7. H.S. Kang, W.Y. Yoon, K.H. Kimc, et al., Effective parameter for the selection of modifying agent for Al-Si alloy, Mater. Sci. Eng. A, 448–451(2007), p.334.

    Article  Google Scholar 

  8. J.Y. Chang, I.G. Moon, and C.S. Choi, Refinement of cast microstructure of hypereutectic Al-Si alloys through the addition of rare earth metals, J. Mater. Sci., 33(1998), No.20, p.5015.

    Article  Google Scholar 

  9. S.Z. Lu and A. Hellawell, The mechanism of silicon modification in aluminum-silicon alloys: impurity induced twinning, Metall. Trans. A, 18(1987), No.10, p.1721.

    Article  Google Scholar 

  10. B.J. Ye, C.R. Looper, D.Y. Lu, and C.S. Kang, An assessment of the role of rare earth in the eutectic modification of cast aluminum-silicon alloys, AFS Trans., 93(1985), p.533.

    Google Scholar 

  11. M.M. Makhlouf and H.V. Guthy, The aluminum-silicon eutectic reaction: mechanisms and crystallography, J. Light Met., 1(2001), No.4, p.199.

    Article  Google Scholar 

  12. F.R. de Boer, R. Boom, W.C.M. Mattens, et al., Cohesion in Metals: Transition Metal Alloys, North-Holland Physics Publishing, Netherlands, 1988, p.1.

    Google Scholar 

  13. K. Nogita, A. Knuutinen, S.D. McDonald, and A.K. Dahle, Mechanisms of eutectic solidification in Al-Si alloys modified with Ba, Ca, Y and Yb, J. Light Met., 1(2001), No.4, p.219.

    Article  Google Scholar 

  14. P. Wang and G.C. Li, Crystallography Course, National Defense Industry Press, Beijing, 2006, p.121.

    Google Scholar 

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Authors and Affiliations

  1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, 710072, China

    Zhong-wei Chen, Cui-ying Ma & Pei Chen

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  1. Zhong-wei Chen
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  2. Cui-ying Ma
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  3. Pei Chen
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Correspondence to Zhong-wei Chen.

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This work was financially supported by the Research Fund of the State Key Laboratory of Solidification Processing (No.42-QP-009), the Open Fund of the State Key Laboratory of Solidification Processing in NWPU (No.201009), the Fundamental Research Fund of Northwestern Polytechnical University (No.JC200929), and the 111 Project of China (No.B08040).

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Chen, Zw., Ma, Cy. & Chen, P. Modifying agent selection for Al-7Si alloy by Miedema model. Int J Miner Metall Mater 19, 131–135 (2012). https://doi.org/10.1007/s12613-012-0527-0

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  • DOI: https://doi.org/10.1007/s12613-012-0527-0

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