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Rare Metals

, Volume 36, Issue 2, pp 95–100 | Cite as

Al–9.00 %Si–0.25 %Mg alloys modified by ytterbium

  • Kun Jia
  • Wen-Bin Yu
  • Jian-Min Yao
  • Shuo Zhang
  • Hao Wu
Article

Abstract

The effects of ytterbium (Yb) on microstructure and solidification behavior of Al–9.00 %Si–0.25 %Mg alloys were investigated. By optical microscope (OM) and scanning electron microscopy (SEM), it is found that the morphology of eutectic silicon changes from coarse plates to fine fibers by the addition of 0.7 %wt Yb. In addition, the grains of α-Al matrix are refined by Yb addition. Phase constitution of the alloy was analyzed by X-ray diffractometer (XRD) and energy dispersive spectroscopy (EDS) attached with SEM and mechanical properties were measured by hardness test. It is concluded that the Yb atoms are incorporated into the silicon by the adsorption at the solid–liquid growth front to cause the modification of eutectic silicon. Furthermore, the results of XRD and EDS analysis reveal that the Yb-containing phase forming in the alloys is Al3Yb.

Keywords

Al–9.00 %Si–0.25 %Mg alloy Yb Modification Eutectic silicon 

Notes

Acknowledgments

This study was financially supported by the Natural Science Foundation Project of Chongqong, Chongqing Science and Technology Commission (No. cstc2012jjA70002) and the National Train Foundation Project of Innovation for Students, Southwest University, China (NO. 201410635002).

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Copyright information

© The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Kun Jia
    • 1
  • Wen-Bin Yu
    • 1
  • Jian-Min Yao
    • 1
  • Shuo Zhang
    • 1
  • Hao Wu
    • 2
  1. 1.School of Materials Science and EngineeringSouthwest UniversityChongqingChina
  2. 2.Guangzhou Automobile Group Motor Co, LtdGuangzhouChina

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