Materials Transactions Online

Materials Transactions, Vol.52 No.04 (2011) pp.753-758
© 2011 The Japan Institute of Metals

Long Time Stability of Pb-Free Sn-9Zn Elements for AC-Low Voltage Fuse Performance

Kazuhiro Matsugi1, Yasuhiro Iwashita1, Yong-Bum Choi1, Gen Sasaki1 and Koji Fujii2

1Area of Mechanical Material Engineering, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
2The Chugoku Electric Power Co. Inc., Hiroshima 730-8701, Japan

In order to evaluate the stability in long time for the performance of AC-low voltage fuses, this study aimed to measure the changes of the specific resistivity, specific heat and thermal conductivity due to the microstructure-change, using a diffusion couple consisting of the Sn-9Zn fuse element and Cu-connector which are exposed at 443 K for 7.2 ks. The reaction area with the thickness of 5 μm consisting of Sn, Cu and Zn phases, was formed at its interface. The values in their properties were increased due to microstructure-change caused by the diffusion. The equations for the estimation of their values could be represented as a function of temperature. The good stability in long time for the un-melt down performance at 210 A of electric current, was confirmed by three-dimensional voltage and temperature calculations on fuse elements after diffusion.

(Received 2010/11/17; Accepted 2011/1/31; Published 2011/3/30)

Keywords: long time stability, lead-free tin-zinc alloys, fuse element, environmentally friendly materials, diffusion, temperature simulation

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  1. S. Jin, D. R. Frear and J. W. Morris, Jr.: J. Electron Mater. 23 (1994) 709–713.
  2. K. Suganuma: Solid State Mater. Sci. 5 (2001) 55–64.
  3. T. Narahashi: Thesis for Master's Degree, Hiroshima University, Higashi-Hiroshima, Japan, (2006) pp.2–5.
  4. O. Yanagisawa, K. Matsugi, Y. Kikuchi, M. Sako, T. Narahashi, K. Fujii, Y. Kumagai and K. Fujita: Sn alloys for electric fuse elements and electric fuses using their elements, Japan Patent, (2009) No.4244035.
  5. Electronic Material Handbook: vol.1, (ASM International, Materials Park, Ohio, 1989) pp.965–966.
  6. P. Biocca: Surf. Mount Technol. 13 (1999) 64–67.
  7. K. Matsugi, G. Sasaki, O. Yanagisawa, Y. Kumagai and K. Fujii: Mater. Trans. 47 (2006) 2413–2420.
  8. W. Yang and R. W. Messler, Jr.: J. Electron Mater. 23 (1994) 765–772.
  9. H. Mavoori, J. Chin, S. Vaynman, B. Moran, L. Keer and ME. Fine: J. Electron Mater. 26 (1997) 783–790.
  10. F. Vnuk, M. Sahoo, D. Baragar and R. W. Smith: J. Mater. Sci. 15 (1980) 2573–2583.
  11. R. Elliott and A. Moore: Scr. Metall. 3 (1969) 249–251.
  12. J. C. Maxwell: A Treatise on Electricity and Magnetism, vol.1, (Oxford Univ. Press, Oxford, 1873) p.365.
  13. R. Landauer: J. Appl. Phys. 23 (1952) 779–784.
  14. K. Matsugi, G. Sasaki, O. Yanagisawa, Y. Kumagai and K. Fujii: Mater. Trans. 48 (2007) 1105–1112.
  15. Y. W. Wang, Y. W. Lin and C. R. Cao: Microscop. Reli. 49 (2009) 248–252.
  16. C. B. Lee, J. W. Yoon, S. J. Suh, S. B. Jung, C. W. Yang, C. C. Shur and Y. E. Shin: J. Mater. Sci. (Mater. in Electronics) 14 (2003) 487–493.


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