Pressureless sintering of β-SiC with Al2O3 additions
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β-SiC was pressureless sintered to 98% theoretical density using Al2O3 as a liquid-phase forming additive. The reaction between SiC and Al2O3 which results in gaseous products, was inhibited by using a pressurized CO gas or, alternatively, a sealed crucible. The densification behaviour and microstructural development of this material are described. The microstructure consists of fine elongated α-SiC grains (maximum length ≈ 10 μm and width 2–3 μm) in a matrix of fine equi-axed grains (2–3 μm) and plate-like grains (2–5μm). The densification behaviour, composition and phases in the sintered product were studied as a function of the sintering parameters and the initial composition. Typically, 50% of the β-phase was transformed to the α-phase.
KeywordsPolymer Microstructure Al2O3 Gaseous Product Material Processing
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- 2.R. M. Williams, B. N. Interbock, S. S. Shinozaki, C. R. Piters and T. J. Whalen, Am. Ceram. Soc. Bull 64  (1985) 1385.Google Scholar
- 3.W. Backer, H. Landfermann and H. Hausner, Powder Metall. Int. 11  (1979) 83.Google Scholar
- 4.K. Suzuki, “Pressureless Sintering of Silicon Carbide with Addition of Aluminium Oxide”, Reports Res. Lab., Asahi Glass Co. Ltd., Japan (1986).Google Scholar
- 5.T. Barrett Jackson, A. Hurford, S. L. Bruner and R. A. Cutler, in “Ceramic Transactions, Silicon Carbide”, 1987, Vol. 2, edited by J. D. Cawley and C. E. Semler (The American Ceramic Society, Westerville, Ohio 1989) pp. 227–40.Google Scholar
- 7.R. A. Cutler and T. B. Jackson, in “Ceramic Materials and Components for Engines”, Proceedings of the Third International Symposium, Las Vegas, NV, Nov. 27–30, 1988, edited by V. J. Tennery (The American Ceramic Society, Westerville, Ohio, 1989) pp. 309–318.Google Scholar
- 8.M. A. Mulla and V. D. Krstic, Am. Ceram. Soc. Bull. 70  (1991) 439.Google Scholar
- 9.M. D. Vlajic and V. D. Krstic, “Densification and Mechanical Properties of Pressureless Sintered B-SiC with Al2O3 and TiO2 Additions”, Presented at Fifth International Symposium on the Science and Technology of Sintering, Vancouver, 1991.Google Scholar
- 12.M. A. Mulla and V. D. Krstic, “Mechanical Properties of β-SiC Pressureless Sintered with Al2O3 Additions”, Acta Metall. Mater, in press.Google Scholar