Surface- and Microanalytical Investigations of the Chemical Constitution of the Grain Boundary Phase in Dense Silicon Nitride

  • H. J. Dudek
  • W. Braue
  • G. Ziegler
Part of the Mikrochimica Acta book series (MIKROCHIMICA, volume 10)


Ceramic materials based on silicon nitride exhibit a greater high temperature strength for temperatures above 1000 °C than conventional super alloys employed at present for turbine engine design. As suitable structural components for high temperature application two groups of Si3N4 materials are of special interest: 1) dense hot-pressed Si3N4 (HPSN) and sintered Si3N4 (SSN) showing strength data between 550 and 900 MN/m2 and 2) reaction-bonded Si3N4 (RBSN) characterized by a residual porosity from 15 to 30% and maximum strength of 350 MN/m2. Further development of dense Si3N4 focuses mainly on the optimization of high-temperature properties. Beside the short-term strength, outstanding properties are the oxidation behavior and the long-term strength under mechanical and cyclic thermal load which can be improved by controlling the microstructure and, in particular, by improving the chemical and structural constitution of the mostly amorphous grain boundary phase. Dense Si3N4 can only be achieved via liquid-phase sintering where in the case of HPSN and SSN MgO, Y2O3 or Y2O3 + A12O3 respectively are usually added as sintering aids. In Fig. 1 the evolution of the liquid-phase sintering process for MgO-fluxed HPSN is demonstrated schematically as proposed by Ref.1. At temperatures below 1400 °C MgO reacts with the amorphous silica layers on the surfaces of α-Si3N4 grains of the starting powder forming magnesium silicate forsterite Mg2SiO4.


Boundary Phase Auger Electron Spectroscopy Triple Junction Auger Parameter Cyclic Thermal Load 
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  1. 1.
    S. Wild. P. Grieveson, K.H. Jack, and M.J. Latimer, Special Ceramics 5, 357 (1972).Google Scholar
  2. 2.
    K.H. Jack, J. Mat. Sci. 11, 1135 (1976).CrossRefGoogle Scholar
  3. 3.
    D.R. Clarke and G. Thomas, J. Am. Ceram. Soc. 60, 491 (1977).CrossRefGoogle Scholar
  4. 4.
    L.K.V. Lou, T.E. Mitchell, and A.H. Heuer, J. Am. Ceram. Soc. 61, 392 (1978).CrossRefGoogle Scholar
  5. 5.
    D.R. Clarke and G. Thomas, J. Am. Ceram. Soc. 61, 114 (1978).CrossRefGoogle Scholar
  6. 6.
    V.N.E. Robinson, Scanning 3, 15 (1980).CrossRefGoogle Scholar
  7. 7.
    F.F. Lange, S.C. Singhal, and R.C. Kuznicki, J. Am. Ceram. Soc. 60, 249 (1977).CrossRefGoogle Scholar
  8. 8.
    L.J. Gauckler, H. Hohnke, and T.Y. Tien, J. Am. Ceram. Soc. 63, 35 (1980).CrossRefGoogle Scholar
  9. 9.
    R.E. Loehman and D.J. Rowcliffe, J. Am. Ceram. Soc. 63, 144 (1980).CrossRefGoogle Scholar
  10. 10.
    D.R. Clarke, N.J. Zaluzec, and R.W. Carpenter, J. Am. Ceram. Soc. 64, 608 (1981).CrossRefGoogle Scholar
  11. 11.
    K.H. Jack, Ceramics for High-Performance Application, Proceedings of the Second Army Materials Technology Conference at Hyannis, Nov. 1973 (Brook Hill, Chestnut Hill, Massachusetts, 1974). p. 265.Google Scholar
  12. 12.
    Y. Oyama and O. Kamigaito, Yogyo Kyokai Shi 81, 290 (1973).CrossRefGoogle Scholar
  13. 13.
    F.F. Lange, Westinghouse Research and Development Center, Pennsylvania, Office of Naval Research Contract Report No TR-9 (Sept. 1976).Google Scholar
  14. 14.
    D.R. Clarke, Ultramicroscopy 4, 33 (1979).CrossRefGoogle Scholar
  15. 15.
    S. Hofmann and L. J. Gauckler, Powder Metallurgy International 6, 90 (1974).Google Scholar
  16. 16.
    S. Hofmann, L. J. Gauckler, and L. Tillmann, Mikrochim. Acta [Wien], Suppl. VI, 1975, 373.Google Scholar
  17. 17.
    P. Greil and J. Weiss, J. Mat. Sci. 17, 1571 (1982).CrossRefGoogle Scholar
  18. 18.
    W. Braue, H.J. Dudek, and G. Ziegler, 5th Proc. Intern. Meeting on Modern Ceramics Technologies (CIMTEC), Lignano/Italy, 14–19 June 1982, in press.Google Scholar
  19. 19.
    J. A. Taylor, Applications of Surface Science 7, 168 (1981).CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Wien 1983

Authors and Affiliations

  • H. J. Dudek
    • 1
  • W. Braue
    • 1
  • G. Ziegler
    • 1
  1. 1.Institut für Werkstoff-ForschungDeutsche Forschungs- und Versuchsanstalt für Luft- und Raumfahrt (DFVLR)Köln 90Federal Republic of Germany

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