The physical chemistry of nucleation of sub-micrometer non-oxide ceramic powders via sub-oxide vapor-phase reduction reaction
- Brunel Univ., Uxbridge (United Kingdom). Dept. of Materials Technology
Fine ceramic powders (< 500 nm) exhibit exceptional physical and mechanical properties in engineered structural ceramics. The production of fine powders, in particular the non-oxide ceramics, via a cheaper route than the organic solvent route has been rather elusive. This paper examines the physical chemistry of sub-oxide vapor-phase reduction reaction for the nucleation of non-oxide ceramic phase. Well known vapor species eg SiO and BO in the production of technical ceramic powders (SiC, BN) are particularly discussed for understanding the nucleation process of SiC and BN ceramic phases respectively. The regimes of partial pressures and temperatures are particularly identified. The calculated nucleation rate as a function of the temperature is compared with the experimental results on powder morphology. The production of amorphous and nanocrystalline h-BN powders is discussed in the context of substrate structure and thermodynamic parameters.
- OSTI ID:
- 367643
- Report Number(s):
- CONF-960202-; ISBN 0-87339-310-4; TRN: IM9640%%389
- Resource Relation:
- Conference: Annual meeting and exhibition of the Minerals, Metals and Materials Society (TMS), Anaheim, CA (United States), 4-8 Feb 1996; Other Information: PBD: 1996; Related Information: Is Part Of Design fundamentals of high temperature composites, intermetallics, and metal-ceramics systems; Lin, R.Y. [ed.] [Univ. of Cincinnati, OH (United States). Dept. of Materials Science and Engineering]; Chang, Y.A. [ed.] [Univ. of Wisconsin, Madison, WI (United States). Dept. of Materials Science and Engineering]; Reddy, R.G. [ed.] [Univ. of Nevada, Reno, NV (United States). Dept. of Chemical and Metallurgical Engineering]; Liu, C.T. [ed.] [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.]; PB: 461 p.
- Country of Publication:
- United States
- Language:
- English
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