Journal of Materials Engineering and Performance

, Volume 26, Issue 4, pp 1605–1613 | Cite as

Effect of Sc and Sr on the Eutectic Si Morphology and Tensile Properties of Al-Si-Mg Alloy



To study the effect of Sc and Sr additions on modifying eutectic silicon particles and mechanical properties for Al-Si-Mg casting alloy, they were added with different amounts in F357 alloy without beryllium addition in the present work. It was found that (0.4 wt.% Sc and 0.04 wt.% Sr)-modified F357 alloy presented the optimal tensile properties when compared with the individual addition of Sc or Sr. This was mainly attributed to the synergic modification of eutectic Si in F357 alloys due to the combined additions of Sc and Sr. The silicon modification mechanisms via Sc and Sr were emphasized to be examined in this paper, and the fracture mechanism of the obtained alloys was also discussed.


Al-Si-Mg mechanical properties microstructure modification Sr and Sc 



The authors are grateful to the financial support by National Natural Science Foundation of China (NSFC, Nos. 51671007, 51671012 and 51401010), the National 863 Project (No. 2013AA031001), the National 973 Project (No. 2012CB619503) and International Science and Technology Cooperation Program of China (Nos. 2015DFA51430, 2013DFB70200) to carry out this work.


  1. 1.
    A. Pacz, ed., 1921. US Patent; p. 13810630Google Scholar
  2. 2.
    S.Z. Lu and A. Hellawell, The Mechanism of Silicon Modification in Aluminum-Silicon Alloys: Impurity Induced Twinning, Metall. Trans. A, 1987, 18(10), p 1721–1733CrossRefGoogle Scholar
  3. 3.
    S.C. Flood and J.D. Hunt, Modification of Al-Si Eutectic Alloys with Na, Metal Sci., 1981, 15(7), p 287–294CrossRefGoogle Scholar
  4. 4.
    J. Sylvain, Modification of AI-Si7-Cu6 by Sodium, Antimony, and Strontium Right Bracket, Fonerie, 1977, 363, p 13–24Google Scholar
  5. 5.
    A.K.P. Rao, K. Das, B.S. Murty, and M. Chakraborty, On the Modification and Segregation Behavior of Sb in Al-7Si Alloy During Solidification, Mater. Lett., 2008, 62(12–13), p 2013–2016CrossRefGoogle Scholar
  6. 6.
    J.H. Li, S. Suetsugu, Y. Tsunekawa, and P. Schumacher, Refinement of Eutectic Si Phase in Al-5Si Alloys with Yb Additions, Metall. Mater. Trans. A, 2013, 44(2), p 669–681CrossRefGoogle Scholar
  7. 7.
    Y.-C. Tsai, C.-Y. Chou, S.-L. Lee, C.-K. Lin, J.-C. Lin, and S.W. Lim, Effect of Trace La Addition on the Microstructures and Mechanical Properties of A356 (Al-7Si-0.35Mg) Aluminum Alloys, J. Alloy. Compd., 2009, 487(1–2), p 157–162CrossRefGoogle Scholar
  8. 8.
    J.H. Li, X.D. Wang, T.H. Ludwig, Y. Tsunekawa, L. Arnberg, J.Z. Jiang, and P. Schumacher, Modification of Eutectic Si in Al-Si Alloys with Eu Addition, Acta Mater., 2015, 84, p 153–163CrossRefGoogle Scholar
  9. 9.
    P. Pandee, C.M. Gourlay, S.A. Belyakov, R. Ozaki, H. Yasuda, and C. Limmaneevichitr, Eutectic Morphology of Al-7Si-0.3 Mg Alloys with Scandium Additions, Metall. Mater. Trans. A, 2014, 45(10), p 4549–4560CrossRefGoogle Scholar
  10. 10.
    W. Prukkanon, N. Srisukhumbowornchai, and C. Limmaneevichitr, Modification of Hypoeutectic Al-Si Alloys with Scandium, J. Alloy. Compd., 2009, 477(1–2), p 454–460CrossRefGoogle Scholar
  11. 11.
    U. Patakham, J. Kajornchaiyakul, and C. Limmaneevichitr, Modification Mechanism of Eutectic Silicon in Al-6Si-0.3 Mg Alloy with Scandium, J. Alloy. Compd., 2013, 575, p 273–284CrossRefGoogle Scholar
  12. 12.
    C. Xu, W. Xiao, S. Hanada, H. Yamagata, and C. Ma, The Effect of Scandium Addition on Microstructure and Mechanical Properties of Al-Si-Mg Alloy: A Multi-Refinement Modifier, Mater. Charact., 2015, 110, p 160–169CrossRefGoogle Scholar
  13. 13.
    C. Xu, W. Xiao, R. Zheng, S. Hanada, H. Yamagata, and C. Ma, The Synergic Effects of Sc and Zr on the Microstructure and Mechanical Properties of Al-Si-Mg Alloy, Mater. Des., 2015, 88, p 485–492Google Scholar
  14. 14.
    L. Lu, K. Nogita, and A.K. Dahle, Combining Sr and Na Additions in Hypoeutectic Al-Si Foundry Alloys, Mater. Sci. Eng., A, 2005, 399(1–2), p 244–253CrossRefGoogle Scholar
  15. 15.
    Y. Dong, R.G. Zheng, X.P. Lin, J. Ye, and L. Sun, Investigation on the Modification Behavior of A356 Alloy Inoculated with a Sr-Y Composite Modifier, J. Rare Earths, 2013, 31(2), p 204–208CrossRefGoogle Scholar
  16. 16.
    ASTM E8. Standard Test Methods for Tension Testing of Metallic Materials (2004).Google Scholar
  17. 17.
    C.H. Caceres, A Rationale for the Quality Index of Al-Si-Mg Casting Alloy, Int. J. Cast Met. Res., 1998, 10, p 293–299CrossRefGoogle Scholar
  18. 18.
    M. Tiryakioğlu, J. Campbell, and N. Alexopoulos, On the Ductility of Cast Al-7 Pct Si-Mg Alloys, Metall. Mater. Trans. A, 2009, 40(4), p 1000–1007CrossRefGoogle Scholar
  19. 19.
    M. Tiryakioğlu, J. Campbell, and N. Alexopoulos, Quality Indices for Aluminum Alloy Castings: A Critical Review, Metall. Mater. Trans. B, 2009, 40(6), p 802–811CrossRefGoogle Scholar
  20. 20.
    M. Tiryakioĝlu and J. Campbell, Quality Index for Aluminum Alloy Castings, AFS Transactions, 2013, 121, p 217–222Google Scholar
  21. 21.
    B. Li, H. Wang, J. Jie, and Z. Wei, Effects of Yttrium and Heat Treatment on the Microstructure and Tensile Properties of Al-7.5Si-0.5Mg Alloy, Mater. Des., 2011, 32(3), p 1617–1622CrossRefGoogle Scholar
  22. 22.
    M. Abdulwahab, I.A. Madugu, S.A. Yaro, S.B. Hassan, and A.P.I. Popoola, Effects of Multiple-Step Thermal Ageing Treatment on THE Hardness Characteristics of A356.0-type Al-Si-Mg Alloy, Mater. Des., 2011, 32(3), p 1159–1166CrossRefGoogle Scholar
  23. 23.
    O. El Sebaie, A.M. Samuel, F.H. Samuel, and H.W. Doty, The Effects of Mischmetal, Cooling Rate and Heat Treatment on the Hardness of A319.1, A356.2 and A413.1 Al-Si Casting Alloys, Mater. Sci. Eng., A, 2008, 486(1–2), p 241–252CrossRefGoogle Scholar
  24. 24.
    M. Abdulwahab, I.A. Madugu, S.A. Yaro, and A.P.I. Popoola, Effects of Temper Conditions and Step–Quenching–Ageing on the Hardness Characteristics and Yield Strength of A356.0-Type Al-Si-Mg Alloy, Silicon, 2012, 4(2), p 137–143CrossRefGoogle Scholar
  25. 25.
    M. Tiryakioğlu, Si particle Size and Aspect Ratio Distributions in an Al-7%Si-0.6%Mg Alloy During Solution Treatment, Mater. Sci. Eng., A, 2008, 473(1–2), p 1–6CrossRefGoogle Scholar
  26. 26.
    M. Tiryakioğlu, The Effect of Solution Treatment and Artificial Aging on the Work Hardening Characteristics of a Cast Al-7%Si-0.6%Mg Alloy, Mater. Sci. Eng., A, 2006, 427(1–2), p 154–159CrossRefGoogle Scholar
  27. 27.
    J.-W. Yeh and W.-P. Liu, The Cracking Mechanism of Silicon Particles in an A357 Aluminum Alloy, Metall. Mater. Trans. A, 1996, 27(11), p 3558–3568CrossRefGoogle Scholar
  28. 28.
    C.H. Caceres and J.R. Griffiths, Damage by the Cracking of Silicon Particles in an Al-7Si-0.4 Mg Casting Alloy, Acta Mater., 1996, 44(1), p 25–33CrossRefGoogle Scholar
  29. 29.
    Q.G. Wang, Microstructural Effects on the Tensile and Fracture Behavior of Aluminum Casting Alloys A356/357, Metall. Mater. Trans. A, 2003, 34(12), p 2887–2899CrossRefGoogle Scholar
  30. 30.
    K. Nogita, S.D. McDonald, and A.K. Dahle, Eutectic Modification of Al-Si Alloys with Rare Earth Metals, Mater. Trans., 2004, 45(2), p 323–326CrossRefGoogle Scholar
  31. 31.
    A. Knuutinen, K. Nogita, S.D. McDonald, and A.K. Dahle, Modification of Al-Si Alloys with Ba, Ca, Y and Yb, J. Light Metals, 2001, 1(4), p 229–240CrossRefGoogle Scholar
  32. 32.
    S.L. Pramod, A.K. Prasada Rao, B.S. Murty, and S.R. Bakshi, Effect of Sc Addition on the Microstructure and wear Properties of A356 Alloy and A356-TiB2 in situ Composite, Mater. Des., 2015, 78, p 85–94CrossRefGoogle Scholar
  33. 33.
    W. Zhang, Y. Liu, J. Yang, J. Dang, H. Xu, and Z. Du, Effects of Sc Content on the Microstructure of As-Cast Al-7wt.% Si Alloys, Mater. Charact., 2012, 66, p 104–110CrossRefGoogle Scholar
  34. 34.
    R. Wagner, On the Growth of Germanium Dendrites, Acta Metall., 1960, 8(1), p 57–60CrossRefGoogle Scholar
  35. 35.
    D.R. Hamilton and R.G. Seidensticker, Propagation Mechanism of Germanium Dendrites, J. Appl. Phys., 1960, 31(7), p 1165–1168CrossRefGoogle Scholar
  36. 36.
    S.-Z. Lu and A. Hellawell, Growth Mechanisms of Silicon in Al-Si Alloys, J. Cryst. Growth, 1985, 73(2), p 316–328CrossRefGoogle Scholar
  37. 37.
    M. Shamsuzzoha and L.M. Hogan, Crystal Morphology of Unmodified Aluminium–Silicon Eutectic Microstructures, J. Cryst. Growth, 1986, 76(2), p 429–439CrossRefGoogle Scholar
  38. 38.
    M. Timpel, N. Wanderka, R. Schlesiger, T. Yamamoto, N. Lazarev, D. Isheim, G. Schmitz, S. Matsumura, and J. Banhart, The Role of Strontium in Modifying Aluminium-Silicon Alloys, Acta Mater., 2012, 60(9), p 3920–3928CrossRefGoogle Scholar
  39. 39.
    H. Huff and D. Gilmer, High Dielectric Constant Materials: VLSI, MOSFET Applications, Springer Science & Business Media, Berlin, 2006Google Scholar
  40. 40.
    G. Azimov, S. Zainabidinov, Y.I. Kozlov, Diffusion of Vanadium in Silicon, ed, American Institute of Physics Circulation Fulfillment Div, 500 Sunnyside Blvd, Woodbury, NY 11797–2999, 1989, pp. 1169–1170Google Scholar
  41. 41.
    D. Fisher, Diffusion in Silicon, Scitec Publications, Zurich, 1998Google Scholar
  42. 42.
    X.H. Zhang, G.C. Su, C.W. Ju, W.C. Wang, and W.L. Yan, Effect of Modification Treatment on the Microstructure and Mechanical Properties of Al-0.35%Mg-7.0%Si Cast Alloy, Mater. Des., 2010, 31(9), p 4408–4413CrossRefGoogle Scholar
  43. 43.
    K. Mills, ASM Handbook, Volume 12: Fractography, ASM International, Materials Park, 1987Google Scholar

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© ASM International 2017

Authors and Affiliations

  1. 1.Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education, School of Material Science and EngineeringBeihang University (BUAA)BeijingPeople’s Republic of China
  2. 2.Institute for Materials ResearchTohoku UniversitySendaiJapan

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