Characterization of Pressureless Sintered Alpha SiC by Advanced Techniques of Scanning Electron Microscopy and X-Ray Diffraction
Sintered alpha-SiC has been investigated by Scanning Electron Microscopy (SEM] and X-Fay diffraction (XRD]. By using channeling contrast effects produced when SEM is operating with low beam energy and high current density, grain size and shape, boron and carbon inclusions, porosity are identified on the same surface without chemical or thermal etching of the samples. From XRD data, by applying the Rietveld method, the weight percentage of SiC polytypes has been evaluated without using standard powder mixtures of alpha-SiC. The percentage of the 4H polytype has been studied as a function of the sintering temperature and has been tentatively related to the presence of exaggerately grown grains.
Unable to display preview. Download preview PDF.
- 1.Prochazka, S., The sintering process for silicon carbide: a review. General Electric Report No. 81CRD314, 1981.Google Scholar
- 2.Bocker, W. and Hausner, H., The influence of boron and carbon additions on the microstructure of sintered alpha silicon carbide. Powder Metall, Int., 1978, 10, 87–89.Google Scholar
- 4.Browning, R., Smialek, J.L. and Jacobs N.S., Multielement mapping of a-SiC by scanning Auger microscopy. Adv. Ceram. Mat., 1987, 2, 773–779.Google Scholar
- 6.Johnson, C.A. and Prochazka, S., Microstructure of sintered SiC. In Ceramic Microstructures’ 76, eds. R.M. Fulrath and J. A. Pask, Westview Press, Boulder, 1977, pp. 366–377.Google Scholar
- 8.Shinozaki, S. S., Hangas, J., Maeda, K. and Soeta, A., Enhanced formation of 4H polytype in silicon carbide materials. In Silicon Carbide’ 87, eds. J. D. Cawley and C.E. Semler, Ceramic Transactions, 1989, 2, 113–120.Google Scholar
- 11.Camanzi, A., Giunta, G., Parretta, A. and Vittori, V., Characterization of ceramic coatings by channeling effects in scanning electron microscopy. In Inst. Phys. Coni. Ser. No. 93, Vol. 2, eds. P.J. Goodhew and H.G. Dickinson, 1988, pp. 525–526.Google Scholar