Journal of Materials Science

, Volume 29, Issue 4, pp 1011–1024 | Cite as

Mechanical properties and microstructure of a P/M aluminium matrix composite with δ-alumina fibres and their relation to extrusion

  • J. H. Ter Haar
  • J. Duszczyk


Saffil short fibre-reinforced aluminium composites have been prepared via a powder metallurgy route. Three different reduction ratios of extrusion were investigated. The tensile mechanical properties at room and elevated temperature and the microstructure, with emphasis on fibre length, were evaluated. The reduction ratio did not influence mean fibre length, implying that during the extrusion the main fibre breakage occurred in the initial compaction stage. The relative strengthening of the unidirectionally reinforced composites at room temperature is low and depends on extrusion reduction ratio. At elevated temperature the strength of the composites in the longitudinal direction is significantly higher compared to that of the base alloy. At 250°C, improvements were obtained of 15%, 24% and 43% for Vf = 0.048, 0.100 and 0.200, respectively. It is suggested that strengthening is possible by the combined effect of a high ductility of the matrix and the resistance to plastic flow exerted by dislocations and stress fields around aligned fibres. All composites contain highly fibre-enriched layers, with bad internal cohesion. They originate from fibre clusters and form severe macroscopic defects during machining operations. Despite that, the tensile properties in the longitudinal direction are reasonably good.


Ductility Longitudinal Direction Powder Metallurgy Fibre Length Aluminium Matrix 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    T. W. Clyne and J. F. Mason, Metall. Trans. 18A (1987) 1519.CrossRefGoogle Scholar
  2. 2.
    T. W. Clyne, M. G. Bader, G. R. Cappleman and P. A. Hubert, J. Mater. Sci. 20 (1985) 85.CrossRefGoogle Scholar
  3. 3.
    A. Sakamoto, H. Hasegawa and Y. Minoda, in “Proceedings of ICCM V,” San Diego, California, July 1985.Google Scholar
  4. 4.
    K. Suganuma, T. Okamoto and N. Suzuki, J. Mater. Sci. Lett. 6 (1987) 1347.CrossRefGoogle Scholar
  5. 5.
    C. A. Stanford-Beale and T. W. Clyne, Comp. Sci. Technol. 35 (1989), 121.CrossRefGoogle Scholar
  6. 6.
    M. Maclean and R. Dower, in “Proceedings of PM'90,” London, UK, July 1990 (The Institute of Metals) p. 251.Google Scholar
  7. 7.
    J. L. Estrada Haen, PhD thesis, Delft University of Technology (1990).Google Scholar
  8. 8.
    J. Zhou and J. Duszczyk, J. Mater. Sci. 25 (1990) 4541.CrossRefGoogle Scholar
  9. 9.
    idem, ibid. 26 (1991) 3737.Google Scholar
  10. 10.
    Saffil Datasheet, ICI Runcorn, UK.Google Scholar
  11. 11.
    J. H. Ter Haar and J. Duszczyk, J. Mater. Sci. in press.Google Scholar
  12. 12.
    idem, Mater. Sci.Eng. A135 (1991) 65.CrossRefGoogle Scholar
  13. 13.
    M. Ichimura, Y. Sasajima and M. Imabayashi, Mater. Trans. JIM 32 (1991) 1109.CrossRefGoogle Scholar
  14. 14.
    idem, ibid. 33 (1992) 449.CrossRefGoogle Scholar
  15. 15.
    W. Thomich, Stahl Eisen 103 (1983) 497.Google Scholar
  16. 16.
    J. H. Ter Haar and J. Duszczyk, in preparation.Google Scholar
  17. 17.
    T. Allen, “Particle size Measurement”, 3rd Edn, Powder Technology Series, (Chapman and Hall, London, 1981) p. 188.CrossRefGoogle Scholar
  18. 18.
    J. H. Ter Haar and J. Duszczyk, J. Mater. Sci. 26 (1991) 3628.CrossRefGoogle Scholar
  19. 19.
    idem. ibid. 27 (1992) 6495.CrossRefGoogle Scholar
  20. 20.
    J. Zhou and J. Duszczyk, J. Mater. Shaping Technol. 6 (1989) 241.CrossRefGoogle Scholar
  21. 21.
    S. Ochiai, T. Araike, K. Tokinori, K. Osamura, M. Nakatani and K. Yamatsuta, J. Mater. Sci. 27 (1992) 4667.CrossRefGoogle Scholar
  22. 22.
    N. Raghunathan, H. B. Mcshane, C. Davies and T. Sheppard, ibid. 25 (1990) 4906.CrossRefGoogle Scholar
  23. 23.
    M. H. Carvalho, T. Marcelo, H. Carcalhinhos and C. M. Cellars, ibid. 27 (1992) 2101.CrossRefGoogle Scholar
  24. 24.
    W. Eichenauer and A. Pebler, Z. Metallkde 48 (1957) 373.Google Scholar
  25. 25.
    C. M. Friend, J. Mater. Sci. 22 (1987) 3005.CrossRefGoogle Scholar
  26. 26.
    M. J. Starink, V. Jooris and P. Van Mourik, in “proceedings of the 12th RISØ International Symposium”, Roskilde, Denmark, September 1991, edited by N. Hansen et al., p. 675.Google Scholar
  27. 27.
    R. J. Arsenault and N. Shi, Mater. Sci. Eng. 81 (1986), 175.CrossRefGoogle Scholar
  28. 28.
    B. Derby and J. R. Walker, Scripta Metall. 22 (1988), 529.CrossRefGoogle Scholar
  29. 29.
    “CRC Handbook of Chemistry and Physics,” 56th Edn (1975–1976) CRC Press, Boca Raton.Google Scholar
  30. 30.
    A. T. Cole, “Lecture Notes International Summerschool on MMCs,” E-MRS May 1990, Klingenthal, France.Google Scholar
  31. 31.
    M. Taya, Mater. Trans JIM 32 (1991) 1.CrossRefGoogle Scholar

Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • J. H. Ter Haar
    • 1
  • J. Duszczyk
    • 1
  1. 1.Laboratory of Materials scienceDelft University of TechnologyAL, DelftThe Netherlands

Personalised recommendations