Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-23T05:35:56.472Z Has data issue: false hasContentIssue false

XRD investigation of Si–SiC composites with fine SiC microstructure

Published online by Cambridge University Press:  05 March 2012

Matthias Wilhelm*
Affiliation:
Institute for Chemical Technology of Inorganic Materials, Vienna University of Technology, Austria
Frank Kubel
Affiliation:
Institute for Mineralogy, Crystallography and Structural Chemistry, Vienna University of Technology, Austria
Werner Wruss
Affiliation:
Institute for Chemical Technology of Inorganic Materials, Vienna University of Technology, Austria
*
a)Author to whom correspondence should be addressed.

Abstract

Si–SiC composite (reaction bonded SiC) with a submicron SiC microstructure (starting SiC particle size: 0.22 μm) was examined by XRD analysis to determine the amount and phase composition of the secondary SiC formed by the reaction between silicon and carbon during the sintering process. It was found that the secondary SiC has grown onto the original hexagonal α-SiC grains as well as into the porosity of the green body. An increase of 3C–SiC was found within the microstructure after infiltration (from 2.6 wt. % before infiltration to 8.8 wt. % after infiltration) whereas the 4H-ploytype content was reduced. This behavior may be explained by the very small original SiC grains which acted as seeds for disoriented SiC growth and were assumed to force the nonepitaxically deposition of secondary SiC. Solid state and fast transportation processes caused the observed transformation of the SiC. Examinations of the silicon source (infiltrant) after the infiltration procedure showed that most of the carbon was converted to SiC with cubic modification (3C stacking sequence)

Type
New Diffraction Data
Copyright
Copyright © Cambridge University Press 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Chakrabarti, O. P., Ghosh, S., and Mukerji, J. (1994). “Influence of grain size, free silicon content and temperature on the strength and toughness of reaction-bonded silicon carbide,” Ceram. Int. CINNDH 20, 283286. cin, CINNDH CrossRefGoogle Scholar
DBWS-9411—An upgrade of the DBWS programs for Rietveld. (1995). “Refinement with PC and mainframe computers,” J. Appl. Crystallogr. 28, 366–367.CrossRefGoogle Scholar
Forrest, C., Kennedy, P., and Shennan, J. (1972). “The fabrication and properties of self-bonded silicon carbide,” Spec. Ceram. SCERAD 5, 99123. 9ct, SCERAD Google Scholar
Jagodzinski, H. (1972). “Transition from cubic to hexagonal silicon carbide as a solid state reaction,” Sov. Phys. Crystallogr. SPHCA6 16, 10811090. spc, SPHCA6 Google Scholar
Jepps, N. W., and Page, T. F. (1979). “Electron microscopy of interfaces between transforming polytypes in silicon carbide,” J. Microsc. JMICAR 116, 159. jmi, JMICAR CrossRefGoogle Scholar
Jepps, N. W., and Page, T. F. (1983). “Polytypic transformations in silicon carbide” in Progress in Crystal Growth and Characterization, edited by P. Krishna (Pergamon, Oxford), Vol. 7, pp. 259–307.Google Scholar
Kabra, V. K., and Pandey, D. (1996). “Evolution of diffuse scattering during 2H to 6H direct transformation in SiC,” Phase Transit. PHTRDP 57, 199223. pht, PHTRDP CrossRefGoogle Scholar
Krauth, A. (1984). “Ingenieurkeramische Bauteile fu¨r Anwendungen in der Energietechnik, Verfahrenstechnik, Metallurgie und Motorenbua,” Keramische Komponenten fu¨r Fahrzeug-Gasturbinen III, 647ff (Springer Verlag).CrossRefGoogle Scholar
Krishna, P., and Marshall, R. C. (1971a). “The structure, perfection and annealing behavior of SiC needles grown by a VLS mechanism,” J. Cryst. Growth JCRGAE 9, 319325. jcr, JCRGAE CrossRefGoogle Scholar
Krishna, P., and Marshall, R. C. (1971b). “Direct transformation from the 2H to 6H structure in single crystal silicon carbides,” J. Cryst. Growth JCRGAE 11, 147150. jcr, JCRGAE CrossRefGoogle Scholar
Lilov, S. K., Tairov, Y. M., Tsvetkov, V. F., and Chernov, M. A. (1976). “Structural and morphological peculiarities of the epitaxial layers and monocrystals of silicon carbide highly doped by nitrogen,” Phys. Status Solidi A PSSABA 37, 143150. psa, PSSABA CrossRefGoogle Scholar
Ness, J. N., and Page, T. F. (1986). “Microstructural evolution in reaction bonded silicon carbide,” J. Mater. Sci. JMTSAS 21, 13771397. jmt, JMTSAS CrossRefGoogle Scholar
Ogbuji, L. U., Mitchell, T. W., Heuer, A. H., and Shinozaki, S. (1979). “Discussions of “Microstructural characterization of REFEL (reaction-bonded) silicon carbides,” J. Mater. Sci. JMTSAS 14, 2267. jmt, JMTSAS CrossRefGoogle Scholar
Pirouz, P., and Yang, J. W. (1993). “Polytypic transformations in SiC: The role of TEM,” Ultramicroscopy ULTRD6 51, 189214. ult, ULTRD6 CrossRefGoogle Scholar
Popper, P. (1960). “The preparation of dense self-bonded silicon carbide,” Spec. Ceram. SCERAD 1, 209219. 9ct, SCERAD Google Scholar
Rosenfolder, O., and Heinrich, J. (1991). “Siliziuminfirtrietes Siliciumcarbide, Festigkeits- und Korrosionseigenschaften,” August, 22–28.Google Scholar
Sawer, G. R., and Page, T. F. (1980). “Discussions of “Microstructural characterization of REFEL (reaction-bonded) silicon carbides:” Authors reply,” J. Mater. Sci. JMTSAS 15, 1850. jmt, JMTSAS Google Scholar
Sekine, T., and Kobayashi, T. (1998). “Shock-induced phase transition of 6H polytype SiC and an implication for post-diamond phase,” AIP Conf. Proc. APCPCS 429 (Shock compression of condensed matter—1997), 141144. apc, APCPCS CrossRefGoogle Scholar
Shaffer, P. T. B. (1969). “Beta silicon carbide,” Mater. Res. Bull. MRBUAC 4, 97106. mrb, MRBUAC Google Scholar
Sorokin, N. D., Tairov, Yu. M.Tsvetkov, V. F., and Chernov, M. A. (1984). “Crystal-chemical properties of the polytypes of silicon carbide,” Sov. Phys. Crystallogr. SPHCA6 28, 539542. spc, SPHCA6 Google Scholar
Thiyagarajan, N., Deb, S., and Mahajan, Y. R. (1995). “Reaction sintering and characterization of Si/SiC composites,” Key Eng. Mater. KEMAEY 108–110, 310. ken, KEMAEY CrossRefGoogle Scholar
Vlaskina, S., and Shin, D. (1999). “6H to 3C polytype transformation in silicon carbide,” Jpn. J. Appl. Phys. JAPNDE 38, 2729. jjb, JAPNDE CrossRefGoogle Scholar