Preparation of Si sub 3 N sub 4 and AlN powders from alkoxide-derived oxides by carbothermal reduction and nitridation
- National Institute for Research in Inorganic Materials, Ibaraki (Japan)
The preparation of Si{sub 3}N{sub 4} and AlN powder was performed by carbothermal reduction and nitridation of silica gel and aluminum hydroxide, respectively. Very fine (<0.1 {mu}m) silica gel or aluminum hydroxide powder was precipitated by the hydrolysis of tetraethyl silicate or aluminum isopropoxide solution, respectively. The precipitate was formed on fine carbon powder dispersed in alkoxide or alkoxide solution. The process gave uniformly mixed starting powders (in situ mixing). The stoichiometric mixtures were heated in flowing nitrogen at 1,430{degree} or 1,500{degree}C. The carbothermal reduction and nitridation reaction was investigated by measuring the weight loss and chemical compositions of powders at intermediate stage of heating. About 8% of the SiO{sub 2} was evaporated as SiO during the preparation of Si{sub 3}N{sub 4}. There was no appreciable evaporation of Al species during the preparation of AlN. Submicrometer Si{sub 3}N{sub 4} and AlN powders were prepared by the present process.
- OSTI ID:
- 6073999
- Journal Information:
- Advanced Ceramic Materials; (USA), Vol. 2:3A; ISSN 0883-5551
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ALUMINIUM NITRIDES
CHEMICAL PREPARATION
SILICON NITRIDES
ALUMINIUM HYDROXIDES
EXPERIMENTAL DATA
NITRIDATION
REDUCTION
SILICA GEL
ADSORBENTS
ALUMINIUM COMPOUNDS
CHEMICAL REACTIONS
DATA
HYDROGEN COMPOUNDS
HYDROXIDES
INFORMATION
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXYGEN COMPOUNDS
PNICTIDES
SILICON COMPOUNDS
SYNTHESIS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication