Journal of Materials Science

, Volume 24, Issue 6, pp 2047–2056 | Cite as

Sinter and sinter-HIP of silicon nitride ceramics with yttria and alumina additions

  • I. Iturriza
  • F. Castro
  • M. Fuentes
Article

Abstract

The sintering behaviour of silicon nitride ceramics has been investigated by preparing powder mixtures containing controlled amounts of yttria and alumina. The fired density of the compacts, having a fixed quantity of yttria, has been observed to increase with increasing amounts of alumina added to the powder. There exists, however, a maximum limit to the beneficial effect of Al2O3, because an excess of alumina in the powder mixture does not produce a further increase in density. Sintering of green compacts, obtained by uniaxial pressing, has been carried out at various temperatures and pressures in order to determine the relationship between fired density and the processing variables. The results obtained, after subjecting a selection of specimens to different sinter-HIP cycles, clearly show that the final density is very sensitive to the applied pressure and the time at which it is applied. The range of microstructures produced by different processing routes has also been followed by electron microscopy. From the results obtained by X-ray diffractometry it is shown that the additions of yttria and alumina not only produce denser specimens than pure silicon nitride, but also promote the α-β transformation.

Keywords

Alumina Al2O3 Nitride Yttria Processing Variable 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    G. R. TERWILLIGER and F. F. LANGE,J. Amer. Ceram. Soc. 57 (1974) 25.Google Scholar
  2. 2.
    ,J. Mater. Sci. 10 (1975) 1169.CrossRefGoogle Scholar
  3. 3.
    R. E. LOEHMAN and D. J. ROWCLIFFE,J. Amer. Ceram. Soc. 63 (1980) 144.Google Scholar
  4. 4.
    L. J. BOWEN, T. G. CARRUTHERS and R. J. BROOK,61 (1978) 335.Google Scholar
  5. 5.
    J. GRESKOVICH and J. H. ROSOLOWSKI,59 (1976) 336.Google Scholar
  6. 6.
    M. SHIMADA, A. TANAKA, T. YAMADA and M. KOIZUMI, in “Ceramic Powder”, edited by P. Vincenzini (Elsevier Scientific, Amsterdam, 1983) pp. 871–9.Google Scholar
  7. 7.
    P. POPPER, in Proceedings of the International Symposium on Factors of Densification and Sintering of Oxide and Non-Oxide Ceramics, Japan 1978, edited by S. Soniya and S. Saito, pp. 19–27.Google Scholar
  8. 8.
    S. HAMPSHIRE and K. H. JACK, in “Special Ceramics 7”, Proceedings of the British Ceramic Society, edited by D. Taylor and P. Popper, December, 1980 (British Ceramic Society, Stoke on Trent, 1981) pp. 37–49.Google Scholar
  9. 9.
    W. D. KINGERY and M. J. BERG,J. Appl. Phys. 26 (1955) 1205.CrossRefGoogle Scholar
  10. 10.
    K. UENO and Y. TOIBANA, NASA Technical Memorandum, NASA TM-77424, Washington (1984).Google Scholar
  11. 11.
    R. R. WILLS, S. HOLINQUIST, J. M. WIMMER and J. A. CUNNINGHAM,J. Mater. Sci. 11 (1976) 1305.Google Scholar
  12. 12.
    G. WOTTING and G. ZIEGLER, in “Ceramic Powder”, edited by P. Vincenzini (Elsevier Scientific, Amsterdam, 1983) pp. 951–62.Google Scholar
  13. 13.
    J. T. SMITH and C. L. QUACKENBUSH, in Proceedings of the International Symposium on Factors of Densification and Sintering of Oxide and Non-oxide Ceramics, Japan, 1978, pp. 426–42.Google Scholar
  14. 14.
    C. GRESKOVICH and C. PROCHAZKA,J. Amer. Ceram. Soc. 60 (1977) 471.Google Scholar
  15. 15.
    H. C. YEH and P. F. SIKORA,Amer. Ceram. Soc. Bull. 58 (1979) 444.Google Scholar
  16. 16.
    O. YEHESKEL, Y. GEFEN and M. J. TALIANKER,J. Mater. Sci. 19 (1984) 745.CrossRefGoogle Scholar
  17. 17.
    C. GRESKOVICH,J. Amer. Ceram. Soc. 64 (1981) 725.Google Scholar
  18. 18.
    B. D. CULLITY, “Elements of X-ray Diffraction”, 2nd Edn (Addison-Wesley, Mass. 1978).Google Scholar
  19. 19.
    G. E. GAZZA,Amer. Ceram. Soc. Bull. 54 (1975) 778.Google Scholar
  20. 20.
    A. ARIAS,J. Mater. Sci. 16 (1981) 787.CrossRefGoogle Scholar
  21. 21.
    F. F. LANGE,Int. Met. Rev. 1 (1980) 1.Google Scholar
  22. 22.
    O. YEHESKEL, Y. GEFEN and M. TALIANKER,J. Mater. Sci. Engng 78 (1986) 209.Google Scholar
  23. 23.
    P. DREW and M. H. LEWIS,J. Mater. Sci. 9 (1974) 261.Google Scholar
  24. 24.
    G. ZIEGLER, J. HEINRICH and G. WOTTING,J. Mater. Sci. 22 (1987) 3041.CrossRefGoogle Scholar
  25. 25.
    I. ITURRIZA, J. ECHEBERRÍA and F. CASTRO, in “Proceedings of the International Conference on Hot Isostatic Pressing of Materials: Applications and Developments”, Antwerp, Belgium, April, 1988, to be published.Google Scholar
  26. 26.
    R. W. K. HONEYCOMBE, “The Plastic Deformation of Metals” (Arnold, London, 1968) Ch. 10.Google Scholar
  27. 27.
    J. W. MARTIN and R. D. DOHERTY, “Stability of Microstructure in Metallic Systems”, Cambridge solid state science series (Cambridge University Press, 1976) Ch. 3.Google Scholar

Copyright information

© Chapman and Hall Ltd. 1989

Authors and Affiliations

  • I. Iturriza
    • 1
  • F. Castro
    • 2
  • M. Fuentes
    • 2
  1. 1.Escuela Superior de Ingenieros IndustrialesUniversidad de NavarraSan SebastiánSpain
  2. 2.Centro de Estudios e Investigaciones Técnicas de GuipúzcoaSan SebastiánSpain

Personalised recommendations