Journal of Electronic Materials

, Volume 48, Issue 5, pp 2660–2669 | Cite as

Effects of Cu and In Trace Elements on Microstructure and Thermal and Mechanical Properties of Sn-Zn Eutectic Alloy

  • P. Pandey
  • C. S. TiwaryEmail author
  • K. Chattopadhyay


The effects of addition of small amounts of copper (Cu) and indium (In) on the microstructure and thermal and mechanical properties of Sn-Zn eutectic alloy have been investigated. Cu and In were added in varying amounts to Sn-14.9 at.%Zn alloy by replacing an equal amount of Sn. Addition of Cu changed the eutectic composition, leading to the appearance of primary phases followed by the formation of intermetallic compounds (IMC) CuZn5 and Cu5Zn8. However, addition of indium (In) did not lead to formation of any new IMCs. With addition of Cu or In to the binary eutectic, the eutectic microstructure coarsened (the eutectic spacing increased). Addition of 1.919 at.% indium decreased the Sn-Zn eutectic temperature from 198.8°C to 192.0°C. On the other hand, addition of Cu did not affect the eutectic temperature as much as In addition did. The mushy (or pasty) range (the temperature range between the eutectic temperature and the melting temperature of the primary phase) increased with addition of Cu or In. Addition of a small amount of copper increased the yield strength of the binary eutectic alloy. The maximum hardness and yield strength of 24 ± 2 HV and 60 ± 3 MPa, respectively, were found with addition of 0.841 at.% Cu; this improvement in strength can be attributed to formation of hard IMCs. In contrast, addition of a small amount of In initially decreased the strength, but the strength increased to 50 MPa at 1.919 at.% In. This can be attributed to the effect of solid-solution strengthening due to the In solute in soft β-Sn.


Lead-free Sn-Zn solder IMC eutectic spacing eutectic temperature pasty range mechanical properties 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Supplementary material

11664_2018_6869_MOESM1_ESM.pdf (853 kb)
Supplementary material 1 (PDF 852 kb)


  1. 1.
    H.H. Manko, Solders and Soldering (New York: McGraw-Hill, 1979).Google Scholar
  2. 2.
    K.-W. Moon, W.J. Boettinger, U.R. Kattner, F.S. Biancaniello, and C.A. Handwerker, J. Electron. Mater. 29, 1122 (2000).CrossRefGoogle Scholar
  3. 3.
    K.S. Kim, S.H. Huh, and K. Suganuma, Mater. Sci. Eng. A 333, 106 (2002).CrossRefGoogle Scholar
  4. 4.
    F. Vnuk, M. Sahoo, D. Baragar, and R.W. Smith, J. Mater. Sci. 15, 2573 (1980).CrossRefGoogle Scholar
  5. 5.
    M. Mccormack and S. Jin, J. Electron. Mater. 23, 715 (1994).CrossRefGoogle Scholar
  6. 6.
    H. Mavoori, J. Chin, S. Vaynman, B. Moran, L. Keer, and M. Fine, J. Electron. Mater. 26, 783 (1997).CrossRefGoogle Scholar
  7. 7.
    M. Abtew and G. Selvaduray, Mater. Sci. Eng. R Rep. 27, 95 (2000).CrossRefGoogle Scholar
  8. 8.
    K. Suganuma and K.-S. Kim, J. Mater. Sci.: Mater. Electron. 18, 121 (2006).Google Scholar
  9. 9.
    Z. Moser, J. Dutkiewicz, W. Gasior, and J. Salawa, Bull. Alloy Phase Diagr. 6, 330 (1985).CrossRefGoogle Scholar
  10. 10.
    M. McCormack and S. Jin, J. Electron. Mater. 23, 635 (1994).CrossRefGoogle Scholar
  11. 11.
    S.C. Cheng and K.L. Lin, J. Electron. Mater. 31, 940 (2002).CrossRefGoogle Scholar
  12. 12.
    J.-M. Song and Z.-M. Wu, Scr. Mater. 54, 1479 (2006).CrossRefGoogle Scholar
  13. 13.
    J.-E. Lee, K.-S. Kim, M. Inoue, J. Jiang, and K. Suganuma, J. Alloys Compd. 454, 310 (2008).CrossRefGoogle Scholar
  14. 14.
    T.-C. Chang, M.-C. Wang, and M.-H. Hon, Metall. Mater. Trans. A 36, 3019 (2005).CrossRefGoogle Scholar
  15. 15.
    S.K. Das, A. Sharif, Y.C. Chan, N.B. Wong, and W.K.C. Yung, J. Alloys Compd. 481, 167 (2009).CrossRefGoogle Scholar
  16. 16.
    K.-I. Chen, S.-C. Cheng, S. Wu, and K.-L. Lin, J. Alloys Compd. 416, 98 (2006).CrossRefGoogle Scholar
  17. 17.
    W. Chen, S. Xue, H. Wang, J. Wang, and Z. Han, J. Mater. Sci.: Mater. Electron. 21, 496 (2010).Google Scholar
  18. 18.
    Y.-S. Kim, K.-S. Kim, C.-W. Hwang, and K. Suganuma, J. Alloys Compd. 352, 237 (2003).CrossRefGoogle Scholar
  19. 19.
    J. Zhou, Y. Sun, and F. Xue, J. Alloys Compd. 397, 260 (2005).CrossRefGoogle Scholar
  20. 20.
    M. McCormack, S. Jin, H.S. Chen, and D.A. Machusak, J. Electron. Mater. 23, 687 (1994).CrossRefGoogle Scholar
  21. 21.
    F. Wang, M. O’Keefe, and B. Brinkmeyer, J. Alloys Compd. 477, 267 (2009).CrossRefGoogle Scholar
  22. 22.
    M. McCormack and S. Jin, JOM 45, 36 (1993).CrossRefGoogle Scholar
  23. 23.
    B.-J. Lee, Calphad 20, 471 (1996).CrossRefGoogle Scholar
  24. 24.
    J.M. Park, N. Mattern, U. Kühn, J. Eckert, K.B. Kim, W.T. Kim, K. Chattopadhyay, and D.H. Kim, J. Mater. Res. 24, 2605 (2009).CrossRefGoogle Scholar
  25. 25.
    S. Kashyap, C.S. Tiwary, and K. Chattopadhyay, Intermetallics 19, 1943 (2011).CrossRefGoogle Scholar
  26. 26.
    C.S. Tiwary, S. Kashyap, and K. Chattopadhyay, Scr. Mater. 93, 20 (2014).CrossRefGoogle Scholar
  27. 27.
    E.R. Wang, X.D. Hui, and G.L. Chen, Mater. Des. 32, 4333 (2011).CrossRefGoogle Scholar
  28. 28.
    J. Jiang, J.-E. Lee, K.-S. Kim, and K. Suganuma, J. Alloys Compd. 462, 244 (2008).CrossRefGoogle Scholar
  29. 29.
    P. Pandey, C.S. Tiwary, and K. Chattopadhyay, J. Electron. Mater. 45, 5468 (2016).CrossRefGoogle Scholar
  30. 30.
    B.-J. Lee, N.M. Hwang, and H.M. Lee, Acta Mater. 45, 1867 (1997).CrossRefGoogle Scholar
  31. 31.
    Y. Cui, X.J. Liu, I. Ohnuma, R. Kainuma, H. Ohtani, and K. Ishida, J. Alloys Compd. 320, 234 (2001).CrossRefGoogle Scholar
  32. 32.
    L. Liu, J.F. Li, and Y.H. Zhou, Acta Mater. 57, 1536 (2009).CrossRefGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  1. 1.Department of Materials EngineeringIndian Institute of ScienceBangaloreIndia

Personalised recommendations