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The Use of Organometallic Precursors to Silicon Nitride as Binders

Published online by Cambridge University Press:  25 February 2011

Stuart T. Schwab
Affiliation:
Southwest Research Institute, Department of Materials Science, 6220 Culebra Road, San Antonio, TX 78284
Cheryl R. Blanchard-Ardid
Affiliation:
Southwest Research Institute, Department of Materials Science, 6220 Culebra Road, San Antonio, TX 78284
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Abstract

Current techniques of advanced ceramic component fabrication are based on pressureless green body consolidation technology in which voids often remain in the final microstructure. Much of this residual porosity is created when the organic binder used to consolidate the ceramic powder burns off on sintering. A new concept in the field of ceramic processing is the use of an organometallic binder material which will pyrolyze on sintering and convert into a predetermined ceramic. Silicon nitride (Si3N4) is a ceramic material in great demand for elevated temperature applications because of its excellent high temperature properties. At the present time, silicon nitride cannot be successfully processed without the use of costly pressure sintering (e.g., hot pressing), or the addition of a glassy phase, which degrades the high temperature properties.

Various preceramic polymers to be used as binders for cold pressing operations have been synthesized and studied. It has been demonstrated that these polymers may be dissolved in an appropriate organic solvent and mixed with a powder. Removal of the solvent yields homogeneous mixtures which may be consolidated into highly dense (> 66% of theoretical) green bodies. The ceramic yields of these polymers have also been determined.

Type
Research Article
Copyright
Copyright © Materials Research Society 1988

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References

REFERENCES

Stock, A. and Somieski, K., Ber, dt. Chem. Ges., 54, 740 (1921).Google Scholar
2. Wynne, K. J. and Rice, R. W., Ann. Rev. Mater. Sci., 14 297 (1984).Google Scholar
3. Beatty, C. L., “Silicon Nitride and Silicon Carbide from Organometallic and Vapor Precursors,” in Ultrastructure Processing of Ceramics, Glasses, and Composites, edited by Hench, L. L. and Ulrich, D. R. (John Wiley and Sons, New York, 1984), pp. 272290 (and references therein).Google Scholar
4. Laine, R. M., Blum, Y. D., and Glasser, D. R., “Synthetic Routes to Oligiosilazanes and Polysilazanes: Polysilazane Precursors to Silicon Nitride,” in Inorganic and Organometallic Polymers (ACS Symposium Series 360) edited by Zeldin, M., Wynne, K. J., Alliock, H. R. (American Chemical Society, Washington, D.C., 1988) pp. 124142 (and references therein).Google Scholar
5a. Seyferth, D. and Wiseman, G. H., “Silazane Precursors to Silicon Nitride,” in Ultrastructure Processing of Ceramics, Glasses and Composites (cited above) pp. 265271.Google Scholar
5b. Seyferth, D., Wiseman, G. H., Poutasse, C.A., Schwark, J. M., Yu, Y. F., Polymer Preprints, 1987, 28 (1) pp. 389392 Google Scholar
5c. Seyferth, D., Wiseman, G. H., Schwark, J. M., Yu, Y. F., and Poutasse, C. A., “Organosilicon Polymers as Precursors for Silicon-Containing Ceramics,” in Inorganic and Organometallic Polymers (cited above) pp. 143155 (and references therein).Google Scholar
6. Shriver, D. F. and Drezdzon, M. A., The Manipulation of Air-Sensitive Compounds, 2nd Ed. (John Wiley and Sons, New York, 1986).Google Scholar
7. Schwab, S. T. and Blanchard-Ardid, C. R., Manuscript in preparation.Google Scholar
8. Schwartz, K. B. and Rowcliffe, D. J., J. Am. Ceram. Soc. 69, C106 (1986).Google Scholar