Densification of alkoxide-derived fine silica powder compact by ultra-high-pressure cold isostatic pressing

Journal Article · Thu Dec 31 23:00:00 EST 1992 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1993.tb03689.x· OSTI ID:6326510

Kamiya, Hidehiro ^[1]; Suzuki, Hisao ^[2]; Kato, Daisuke; Jimbo, Genji ^[1]

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1. Nagoya Univ., Nagoya (Japan). Dept. of Chemical Engineering
2. Toyota Technological Inst., Nagoya (Japan)

Powder compacts of alkoxide-derived fine silica powders were consolidated into a highly dense and uniform structure by ultra-high-pressure cold isostatic pressing of granules with controlled structure. The diameters of spherical and nearly monosized amorphous silica particles, prepared from metal alkoxide, were successfully controlled in the range of 9 to 760 nm by varying the concentration of ammonia. Close-packed granules of these powders were produced by spray drying. These powders were isostatically pressed up to 1 GPa at room temperature. Although the average particle diameter was less than 100 nm, the maximum relative density of the compacts was more than 78% of theoretical density. The optimum particle size to obtain highly dense compacts was in the range of 30 to 300 nm at 1 GPa. Furthermore, the ratio of mode pore diameter in these compacts to particle diameter was less than 0.155, which corresponded to the minimum ratio of calculated three-particle pore channel radii for hexagonal close packing. Viscous deformation of particles under ultra-high isostatic pressure played an important role in the densification of the compacts.

• OSTI ID: 6326510
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 76:1; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
ALKOXIDES
AMMONIA
CHALCOGENIDES
COLD PRESSING
COMPACTS
DEFORMATION
DENSITY
DISPERSIONS
DRYING
FABRICATION
HIGH PRESSURE
HYDRIDES
HYDROGEN COMPOUNDS
MATERIALS WORKING
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
PHYSICAL PROPERTIES
POROSITY
POWDERS
PRESSING
SILICON COMPOUNDS
SILICON OXIDES
SIZE
SPRAY DRYING
SUSPENSIONS