Effect of sintering additives on the behaviour of SiC whisker-reinforced Si3N4 composites
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The effects of sintering additives on the microstructural development, whisker stability, oxidation resistance and room-temperature mechanical properties of the SiC whisker-reinforced Si3N4 matrix composites were investigated. Seven different combinations of Y2O3 and Al2O3 were used as sintering additives. The composites containing 20 vol % SiC whiskers were densified by hot pressing. The microstructure of the resulting composites was characterized using X-ray diffraction, scanning and transmission electron microscopy. Oxidation testing of the composite at 1400 °C was conducted to investigate the relationship between matrix compositions and oxidation resistance. The flexural strength, fracture toughness and crack propagation patterns were also characterized and correlated with the microstructural features.
KeywordsMicrostructure Transmission Electron Microscopy Al2O3 Fracture Toughness Y2O3
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- 1.P. F. Becher and T. N. Tiegs, “Engineering Materials Handbook”, Vol. 1, “Composites” (ASM International. Materials Park, OH, 1987) p. 941.Google Scholar
- 3.S.-T. Buljan, A. E. Pasto and H. J. Kim, Amer. Ceram. Soc. Bull. 68 (1989) 387.Google Scholar
- 5.S. T. Buljan and V. K. Sarin, in “Sintered Metal-Matrix Composite”, edited by G. S. Upadhyaya (Elsevier Science, Amsterdam, 1984) p. 45.Google Scholar
- 6.P. F. Becher, T. N. Tiegs, J. C. Ogle and W. H. Warwick, in “Fracture Mechanics of Ceramics”, Vol. 7, edited by R. C. Bradt, A. G. Evans, D. P. H. Hasselman and F. F. Lange (Plenum, New York, 1985) p. 61.Google Scholar
- 10.C. P. Gazzara and D. R. Messier, Amer. Ceram. Soc. Bull. 56 (1977) 777.Google Scholar
- 11.“1989 Annual Book of ASTM Standards”, Vol. 03.01 (ASTM Easton, MD, 1989).Google Scholar
- 17.M. E. Washburn, Amer. Ceram. Soc. Bull. 46 (1967) 667.Google Scholar
- 20.J. Ito and H. Johnson, Amer. Mineral. 53 (1968) 1940.Google Scholar
- 22.R. F. Davis and C. H. Carter Jr, in “Advanced Ceramics”. edited by S. Saito (Oxford University Press and Ohmsha Ltd, Oxford, 1988).Google Scholar